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-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/ASMPrinter.java140
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/Ary.java217
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/CodeGen.java288
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java241
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/GraphVisualizer.java288
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/IRPrinter.java279
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/IterPeeps.java196
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/JSViewer.java402
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/ListScheduler.java231
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/Machine.java21
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/Parser.java1729
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/RegMask.java39
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/SB.java91
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/SimpleWebSocket.java148
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/Utils.java53
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/Var.java55
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/AddFNode.java44
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/AddNode.java190
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/AndNode.java58
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/BoolNode.java134
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/CFGNode.java162
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/CProjNode.java62
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/CallEndNode.java90
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/CallNode.java146
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/CastNode.java58
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ConstantNode.java70
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/CtrlNode.java15
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/DivFNode.java46
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/DivNode.java46
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/FRefNode.java35
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/FunNode.java149
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/IfNode.java69
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/LoadNode.java210
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/LogicalNode.java29
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/LoopNode.java86
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MachConcreteNode.java27
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MachNode.java49
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MemMergeNode.java154
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MemOpNode.java74
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MinusFNode.java36
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MinusNode.java40
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MulFNode.java51
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MulNode.java81
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/MultiNode.java29
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/NeverNode.java21
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/NewNode.java83
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/Node.java640
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/NotNode.java32
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/OrNode.java55
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ParmNode.java48
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/PhiNode.java201
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ProjNode.java55
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ReadOnlyNode.java30
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/RegionNode.java126
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ReturnNode.java129
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/RoundF32Node.java38
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/SarNode.java50
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ScopeNode.java428
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ShlNode.java53
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ShrNode.java46
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/StartNode.java58
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/StopNode.java64
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/StoreNode.java113
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/StructNode.java46
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/SubFNode.java44
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/SubNode.java59
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/ToFloatNode.java34
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/XCtrlNode.java16
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/XorNode.java54
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddFMemX86.java33
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddFX86.java29
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddIX86.java39
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddMemX86.java25
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddX86.java29
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AndIX86.java42
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CallRX86.java31
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CallX86.java40
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpIX86.java43
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpMemX86.java33
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpX86.java27
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/DivFX86.java33
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/DivX86.java31
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/FltX86.java36
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/FunX86.java21
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/I2f8X86.java28
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/IntX86.java45
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/JmpX86.java46
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/LeaX86.java42
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/LoadX86.java25
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MemAddX86.java28
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MemOpX86.java87
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulFX86.java30
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulIX86.java36
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulX86.java30
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/NewX86.java40
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/OrIX86.java44
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ParmX86.java24
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ProjX86.java23
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/RetX86.java48
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SarX86.java40
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SetX86.java39
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ShlIX86.java38
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ShrIX86.java39
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/StoreX86.java30
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SubFX86.java29
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SubX86.java29
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/TFPX86.java41
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/XorIX86.java42
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/x86_64_v2.java418
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/Field.java74
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/Type.java235
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeFloat.java95
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeFunPtr.java104
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeInteger.java128
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeMem.java74
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java105
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeNil.java62
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypePtr.java53
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeRPC.java100
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeStruct.java248
-rw-r--r--chapter20/src/main/java/com/seaofnodes/simple/type/TypeTuple.java97
121 files changed, 12369 insertions, 0 deletions
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/ASMPrinter.java b/chapter20/src/main/java/com/seaofnodes/simple/ASMPrinter.java
new file mode 100644
index 00000000..5cc13210
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/ASMPrinter.java
@@ -0,0 +1,140 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.type.TypeFunPtr;
+import com.seaofnodes.simple.type.TypeMem;
+import com.seaofnodes.simple.type.TypeRPC;
+
+public abstract class ASMPrinter {
+
+ public static SB print(SB sb, CodeGen code) {
+ if( code._cfg==null )
+ return sb.p("Need _cfg set, run after GCM");
+
+ // instruction address
+ int iadr = 0;
+ for( int i=0; i<code._cfg._len; i++ )
+ if( code._cfg.at(i) instanceof FunNode fun )
+ iadr = print(iadr,sb,code,fun,i);
+ return sb;
+ }
+
+ private static int print(int iadr, SB sb, CodeGen code, FunNode fun, int cfgidx) {
+ // Function header
+ sb.nl().p("---");
+ fun.sig().print(sb);
+ sb.p("---------------------------").nl();
+
+
+ while( !(code._cfg.at(cfgidx) instanceof ReturnNode) )
+ iadr = doBlock(iadr,sb,code,fun,cfgidx++);
+
+ // Function separator
+ sb.p("---");
+ fun.sig().print(sb);
+ sb.p("---------------------------").nl();
+ return iadr;
+ }
+
+ static int doBlock(int iadr, SB sb, CodeGen code, FunNode fun, int cfgidx) {
+ CFGNode bb = code._cfg.at(cfgidx);
+ if( bb != fun && !(bb instanceof IfNode) && !(bb instanceof CallEndNode) && !(bb instanceof CallNode) && !(bb instanceof CProjNode && bb.in(0) instanceof CallEndNode ))
+ sb.p("L").p(bb._nid).p(":").nl();
+
+ if( !(bb instanceof CallNode) )
+ for( Node n : bb._outputs )
+ iadr = doInst(iadr, sb,code,fun,bb,n);
+
+ return iadr;
+ }
+
+ static int doInst(int iadr, SB sb, CodeGen code, FunNode fun, CFGNode bb, Node n) {
+ final int encWidth = 8;
+ final int opWidth = 5;
+ final int argWidth = 30;
+
+ if( n instanceof CProjNode ) return iadr;
+
+ // Phis are useful before (and during) reg alloc
+ if( n instanceof PhiNode phi ) {
+ if( phi._type instanceof TypeMem || phi._type instanceof TypeRPC ) return iadr; // Nothing for the hidden ones
+ sb.fix(4," ").p(" ").fix(encWidth,"").p(" ").fix(opWidth,phi._label).p(" ");
+ sb.p(code.reg(n));
+ if( !(n instanceof ParmNode) ) {
+ sb.p(" = phi( ");
+ for( int i=1; i<n.nIns(); i++ )
+ sb.p("N").p(n.in(i)._nid).p(",");
+ sb.unchar().p(" )");
+ }
+ sb.nl();
+ return iadr;
+ }
+
+ // All blocks ending in a Region will need to either fall into or jump
+ // to this block. Until the post-reg-alloc block layout cleanup, we
+ // need to assume a jump. There's no real hardware op here, yet.
+ if( n instanceof RegionNode && !(n instanceof FunNode) ) {
+ sb.hex4(iadr++).p(" ").fix(encWidth,"??").p(" ").fix(opWidth,"JMP").p(" ").fix(argWidth,"L"+n._nid).nl();
+ return iadr;
+ }
+
+ // ProjNodes following a multi (e.g. Call or New results),
+ // get indent slightly and just print their index & node#
+ if( n instanceof ProjNode proj ) {
+ if( proj._type instanceof TypeMem ) return iadr; // Nothing for the hidden ones
+ sb.fix(4," ").p(" ").fix(encWidth,"").p(" ").fix(opWidth,proj._label==null ? "---" : proj._label).p(" ").p(code.reg(n)).nl();
+ return iadr;
+ }
+
+ // ADDR ENCODING Op--- dst = src op src // Comment
+ // 1234 abcdefgh ld4 RAX = [Rbase + off] // Comment
+ sb.hex4(iadr);
+ sb.p(" ");
+
+ // Encoding
+ int size = 1; // TODO: Fake encoding size
+ iadr += size;
+ sb.fix(encWidth,"??");
+ sb.p(" ");
+
+ // Op; generally "ld4" or "call"
+ sb.fix(opWidth, n instanceof MachNode mach ? mach.op() : n.label());
+ sb.p(" ");
+
+ // General asm args
+ if( n instanceof MachNode mach ) {
+ int old = sb.len();
+ mach.asm(code,sb);
+ sb.fix(argWidth-(sb.len()-old),""); // Pad out
+
+ } else if( !(n._type instanceof TypeMem) ) {
+ // Room for some inputs
+ sb.fix(5, n._nid+":" );
+ int off = 0;
+ for( int i=0; i<n.nIns(); i++ ) {
+ sb.fix(5, n.in(i) == null ? "___" : String.valueOf(n.in(i)._nid));
+ off += 5;
+ if( off >= argWidth ) break;
+ }
+ if( off < argWidth ) sb.fix(argWidth-off,"");
+ }
+ sb.p(" ");
+
+ // Comment
+ String comment = n.comment();
+ if( comment!=null ) sb.p("// ").p(comment);
+
+ sb.nl();
+
+ // MultiNodes are immediately followed by projection(s)
+ if( !(n instanceof CFGNode) && n instanceof MultiNode ) {
+ for( Node proj : n._outputs ) {
+ assert proj instanceof ProjNode;
+ doInst(iadr,sb,code,fun,bb,proj);
+ }
+ }
+
+ return iadr;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/Ary.java b/chapter20/src/main/java/com/seaofnodes/simple/Ary.java
new file mode 100644
index 00000000..73ada8e0
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/Ary.java
@@ -0,0 +1,217 @@
+package com.seaofnodes.simple;
+
+import java.lang.StringBuilder;
+import java.lang.reflect.Array;
+import java.util.*;
+
+// ArrayList with saner syntax
+public class Ary<E> extends AbstractList<E> implements List<E> {
+ public E[] _es;
+ public int _len;
+
+ public Ary(E[] es) { this(es,es.length); }
+ public Ary(E[] es, int len) { if( es.length==0 ) es=Arrays.copyOf(es,1); _es=es; _len=len; }
+ @SuppressWarnings("unchecked")
+ public Ary(Class<E> clazz) { this((E[]) Array.newInstance(clazz, 1),0); }
+
+ /** @return list is empty */
+ public boolean isEmpty() { return _len==0; }
+ /** @return active list length */
+ public int len() { return _len; }
+ public int size() { return len(); }
+
+ /** @param i element index
+ * @return element being returned; throws if OOB
+ * @exception AIOOBE if !(0 <= i < _len)
+ */
+ public E get( int i ) { return at(i); }
+ public E at( int i ) {
+ range_check(i);
+ return _es[i];
+ }
+
+ /** @return last element */
+ public E last( ) { return at(_len-1); }
+
+ /** Add element in amortized constant time
+ * @param e Element to add at end of list
+ **/
+ public E push( E e ) {
+ if( _len >= _es.length ) _es = Arrays.copyOf(_es,Math.max(1,_es.length<<1));
+ return (_es[_len++] = e);
+ }
+ /** @return remove and return last element */
+ public E pop( ) {
+ return _len==0 ? null : _es[--_len];
+ }
+ @Override public E removeLast() { return pop(); }
+
+
+ /** Add element in amortized constant time
+ * @param e Element to add at end of list
+ * @return true */
+ public boolean add( E e ) {
+ if( _len >= _es.length ) _es = Arrays.copyOf(_es,Math.max(1,_es.length<<1));
+ _es[_len++] = e;
+ return true;
+ }
+
+ /** Fast, constant-time, element removal. Does not preserve order
+ * @param i element to be removed
+ * @return element removed */
+ public E del( int i ) {
+ range_check(i);
+ E tmp = _es[i];
+ _es[i]=_es[--_len];
+ return tmp;
+ }
+
+ /** Slow, linear-time, element removal. Preserves order.
+ * @param i element to be removed
+ * @return element removed */
+ @Override public E remove( int i ) {
+ range_check(i);
+ E e = _es[i];
+ System.arraycopy(_es,i+1,_es,i,(--_len)-i);
+ return e;
+ }
+
+ /** Remove all elements */
+ public void clear( ) { _len=0; }
+
+ /** Set existing element
+ * @param i element to set
+ * @param e value to set
+ * @return old value
+ * @exception AIOOBE if !(0 <= i < _len)
+ */
+ public E set( int i, E e ) {
+ range_check(i);
+ E old = _es[i];
+ _es[i] = e;
+ return old;
+ }
+
+ /** Set existing element
+ * @param i element to set
+ * @param e value to set
+ * @return old value
+ * @exception AIOOBE if !(0 <= i < _len)
+ */
+ public E setX( int i, E e ) {
+ if( i >= _len ) {
+ while( i >= _es.length ) _es = Arrays.copyOf( _es, _es.length << 1 );
+ _len = i+1;
+ }
+ E old = _es[i];
+ _es[i] = e;
+ return old;
+ }
+
+ public Ary<E> setLen( int len ) {
+ if( len > _len )
+ while( len>= _es.length ) _es = Arrays.copyOf(_es,_es.length<<1);
+ _len = len;
+ while( _es.length > (len<<1) ) // Shrink if hugely too large
+ _es = Arrays.copyOf(_es,_es.length>>1);
+ Arrays.fill(_es,len,_es.length,null);
+ return this;
+ }
+
+ public E swap( int i, int j ) {
+ range_check(i);
+ range_check(j);
+ E tmp = _es[i];
+ if( i==j ) return tmp;
+ _es[i] = _es[j];
+ _es[j] = tmp;
+ return tmp;
+ }
+
+
+ /** @param c Collection to be added */
+ public boolean addAll( Collection<? extends E> c ) {
+ if( c==null ) return false;
+ for( E e : c ) add(e);
+ return true;
+ }
+ public Ary<E> addAll( Iterable<? extends E> it ) { for( E e : it ) add(e); return this; }
+
+ /** @param es Array to be added */
+ public <F extends E> Ary<E> addAll( F[] es ) {
+ if( es==null || es.length==0 ) return this;
+ while( _len+es.length > _es.length ) _es = Arrays.copyOf(_es,_es.length<<1);
+ System.arraycopy(es,0,_es,_len,es.length);
+ _len += es.length;
+ return this;
+ }
+
+ /** @param c Collection to be added */
+ public Ary<E> addAll( Ary<? extends E> c ) {
+ if( c==null || c._len==0 ) return this;
+ while( _len+c._len > _es.length ) _es = Arrays.copyOf(_es,_es.length<<1);
+ System.arraycopy(c._es,0,_es,_len,c._len);
+ _len += c._len;
+ return this;
+ }
+
+ /** @return compact array version */
+ public E[] asAry() { return Arrays.copyOf(_es,_len); }
+
+ /** Sorts in-place
+ * @param c Comparator to sort by */
+ public void sort_update(Comparator<? super E> c ) { Arrays.sort(_es, 0, _len, c); }
+
+ /** Find the first matching element using ==, or -1 if none. Note that
+ * most del calls shuffle the list, so the first element might be random.
+ * @param e Element to find
+ * @return index of first matching element, or -1 if none */
+ public int find( E e ) {
+ for( int i=0; i<_len; i++ ) if( _es[i]==e ) return i;
+ return -1;
+ }
+
+
+ /** @return an iterator */
+ @Override public Iterator<E> iterator() { return new Iter(); }
+ private class Iter implements Iterator<E> {
+ int _i=0;
+ @Override public boolean hasNext() { return _i<_len; }
+ @Override public E next() { return _es[_i++]; }
+ }
+
+ @Override public String toString() {
+ StringBuilder sb = new StringBuilder().append('{');
+ for( int i=0; i<_len; i++ ) {
+ if( i>0 ) sb.append(',');
+ if( _es[i] != null ) sb.append(_es[i].toString());
+ }
+ return sb.append('}').toString();
+ }
+
+ private void range_check( int i ) {
+ if( i < 0 || i>=_len )
+ throw new ArrayIndexOutOfBoundsException(""+i+" >= "+_len);
+ }
+
+ // Note that the hashCode() and equals() are not invariant to changes in the
+ // underlying array. If the hashCode() is used (e.g., inserting into a
+ // HashMap) and the then the array changes, the hashCode() will change also.
+ @Override public boolean equals( Object o ) {
+ if( this==o ) return true;
+ if( !(o instanceof Ary ary) ) return false;
+ if( _len != ary._len ) return false;
+ if( _es == ary._es ) return true;
+ for( int i=0; i<_len; i++ )
+ if( !(_es[i]==null ? (ary._es[i] == null) : _es[i].equals(ary._es[i])) )
+ return false;
+ return true;
+ }
+ @Override public int hashCode( ) {
+ int sum=_len;
+ for( int i=0; i<_len; i++ )
+ sum += _es[i]==null ? 0 : _es[i].hashCode();
+ return sum;
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/CodeGen.java b/chapter20/src/main/java/com/seaofnodes/simple/CodeGen.java
new file mode 100644
index 00000000..c48a4162
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/CodeGen.java
@@ -0,0 +1,288 @@
+ package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.node.cpus.x86_64_v2.MemOpX86;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+import java.util.HashMap;
+import java.util.IdentityHashMap;
+
+public class CodeGen {
+ // Last created CodeGen as a global; used all over to avoid passing about a
+ // "context".
+ public static CodeGen CODE;
+
+ public enum Phase {
+ Parse, // Parse ASCII text into Sea-of-Nodes IR
+ Opto, // Run ideal optimizations
+ TypeCheck, // Last check for bad programs
+ InstructionSelection, // Convert to target hardware nodes
+ Schedule, // Global schedule (code motion) nodes
+ LocalSched, // Local schedule
+ RegAlloc; // Register allocation
+ }
+ public enum CallingConv {
+ Win64,
+ SystemV
+ }
+ public Phase _phase;
+
+ // ---------------------------
+ // Compilation source code
+ public final String _src;
+ // Compile-time known initial argument type
+ public final TypeInteger _arg;
+ public CallingConv _callingConv;
+
+ // ---------------------------
+ public CodeGen( String src ) { this(src, TypeInteger.BOT, 123L ); }
+ public CodeGen( String src, TypeInteger arg, long workListSeed ) {
+ CODE = this;
+ _phase = null;
+ _callingConv = null;
+ _start = new StartNode(arg);
+ _stop = new StopNode(src);
+ _src = src;
+ _arg = arg;
+ _iter = new IterPeeps(workListSeed);
+ P = new Parser(this,arg);
+ }
+
+
+ // ---------------------------
+ /**
+ * A counter, for unique node id generation. Starting with value 1, to
+ * avoid bugs confusing node ID 0 with uninitialized values.
+ */
+ private int _uid = 1;
+ public int UID() { return _uid; }
+ public int getUID() { return _uid++; }
+
+ // Next available memory alias number
+ private int _alias = 2; // 0 is for control, 1 for memory
+ public int getALIAS() { return _alias++; }
+
+
+ // Popular visit bitset, declared here, so it gets reused all over
+ public final BitSet _visit = new BitSet();
+ public BitSet visit() { assert _visit.isEmpty(); return _visit; }
+
+ // Start and stop; end points of the generated IR
+ public StartNode _start;
+ public StopNode _stop;
+
+ // Global Value Numbering. Hash over opcode and inputs; hits in this table
+ // are structurally equal.
+ public final HashMap<Node,Node> _gvn = new HashMap<>();
+
+ // Compute "function indices": FIDX.
+ // Each new request at the same signature gets a new FIDX.
+ private final HashMap<TypeTuple,Integer> FIDXS = new HashMap<>();
+ public TypeFunPtr makeFun( TypeTuple sig, Type ret ) {
+ Integer i = FIDXS.get(sig);
+ int fidx = i==null ? 0 : i;
+ FIDXS.put(sig,fidx+1); // Track count per sig
+ assert fidx<64; // TODO: need a larger FIDX space
+ return TypeFunPtr.make((byte)2,sig,ret, 1L<<fidx );
+ }
+ // Signature for MAIN
+ public TypeFunPtr _main = makeFun(TypeTuple.MAIN,Type.BOTTOM);
+ // Reverse from a constant function pointer to the IR function being called
+ public FunNode link( TypeFunPtr tfp ) {
+ assert tfp.isConstant();
+ return _linker.get(tfp.makeFrom(Type.BOTTOM));
+ }
+
+ // Insert linker mapping from constant function signature to the function
+ // being called.
+ public void link(FunNode fun) {
+ _linker.put(fun.sig().makeFrom(Type.BOTTOM),fun);
+ }
+
+ // "Linker" mapping from constant TypeFunPtrs to heads of function. These
+ // TFPs all have exact single fidxs and their return is wiped to BOTTOM (so
+ // the return is not part of the match).
+ private final HashMap<TypeFunPtr,FunNode> _linker = new HashMap<>();
+
+ // Parser object
+ public final Parser P;
+
+ // Parse ASCII text into Sea-of-Nodes IR
+ public CodeGen parse() {
+ assert _phase == null;
+ _phase = Phase.Parse;
+
+ P.parse();
+ JSViewer.show();
+ return this;
+ }
+
+
+ // ---------------------------
+ // Iterator peepholes.
+ public final IterPeeps _iter;
+ // Stop tracking deps while assertin
+ public boolean _midAssert;
+ // Statistics on peepholes
+ public int _iter_cnt, _iter_nop_cnt;
+ // Stat gathering
+ public void iterCnt() { if( !_midAssert ) _iter_cnt++; }
+ public void iterNop() { if( !_midAssert ) _iter_nop_cnt++; }
+
+ // Run ideal optimizations
+ public CodeGen opto() {
+ assert _phase == Phase.Parse;
+ _phase = Phase.Opto;
+
+ // Pessimistic peephole optimization on a worklist
+ _iter.iterate(this);
+
+ // TODO:
+ // Optimistic
+ // TODO:
+ // loop unroll, peel, RCE, etc
+ return this;
+ }
+ public <N extends Node> N add( N n ) { return (N)_iter.add(n); }
+ public void addAll( Ary<Node> ary ) { _iter.addAll(ary); }
+
+
+ // ---------------------------
+ // Last check for bad programs
+ public CodeGen typeCheck() {
+ // Demand phase Opto for cleaning up dead control flow at least,
+ // required for the following GCM.
+ assert _phase.ordinal() <= Phase.Opto.ordinal();
+ _phase = Phase.TypeCheck;
+
+ Parser.ParseException err = _stop.walk( Node::err );
+ if( err != null )
+ throw err;
+ return this;
+ }
+
+
+ // ---------------------------
+ // Code generation CPU target
+ public Machine _mach;
+
+ // Convert to target hardware nodes
+ public CodeGen instSelect( String cpu, String callingConv ) {
+ assert _phase.ordinal() <= Phase.TypeCheck.ordinal();
+ _phase = Phase.InstructionSelection;
+
+ _callingConv = switch(callingConv) {
+ case "SystemV" -> CallingConv.SystemV;
+ case "Win64" -> CallingConv.Win64;
+ default -> throw Utils.TODO(); // Unknown calling convention
+ };
+
+ // Look for CPU in fixed named place:
+ // com.seaofnodes.simple.node.cpus."cpu"."cpu.class"
+ String clzFile = "com.seaofnodes.simple.node.cpus."+cpu+"."+cpu;
+ try { _mach = ((Class<Machine>) Class.forName( clzFile )).getDeclaredConstructor().newInstance(); }
+ catch( Exception e ) { throw new RuntimeException(e); }
+
+ // Convert to machine ops
+ _uid = 1; // All new machine nodes reset numbering
+ var map = new IdentityHashMap<Node,Node>();
+ _instSelect( _stop, map );
+ _stop = ( StopNode)map.get(_stop );
+ _start = (StartNode)map.get(_start);
+ _instOuts(_stop,visit());
+ _visit.clear();
+ return this;
+ }
+
+ // Walk all ideal nodes, recursively mapping ideal to machine nodes, then
+ // make a machine node for "this".
+ private Node _instSelect( Node n, IdentityHashMap<Node,Node> map ) {
+ if( n==null ) return null;
+ Node x = map.get(n);
+ if( x !=null ) return x; // Been there, done that
+
+ // If n is a MachConcrete, then its part of a multi-node expansion.
+ // It does not need instruction selection (already selected!)
+ // but it does need its inputs walked.
+ if( n instanceof MachConcreteNode || n instanceof MemOpX86 ) {
+ for( int i=0; i < n.nIns(); i++ )
+ n._inputs.set(i, _instSelect(n.in(i),map) );
+ return n;
+ }
+
+ // Produce a machine node from n; map it to flag as done so stops cycles.
+ map.put(n, x=_mach.instSelect(n) );
+ // Walk machine op and replace inputs with mapped inputs
+ for( int i=0; i < x.nIns(); i++ )
+ x._inputs.set(i, _instSelect(x.in(i),map) );
+ if( x instanceof MachNode mach )
+ mach.postSelect(); // Post selection action
+
+ // Updates forward edges only.
+ n._outputs.clear();
+ return x;
+ }
+
+ // Walk all machine Nodes, and set their output edges
+ private void _instOuts( Node n, BitSet visit ) {
+ if( visit.get(n._nid) ) return;
+ visit.set(n._nid);
+ for( Node in : n._inputs )
+ if( in!=null ) {
+ in._outputs.push(n);
+ _instOuts(in,visit);
+ }
+ }
+
+
+ // ---------------------------
+ // Control Flow Graph in RPO order.
+ Ary<CFGNode> _cfg = new Ary<>(CFGNode.class);
+
+ // Global schedule (code motion) nodes
+ public CodeGen GCM() { return GCM(false); }
+ public CodeGen GCM( boolean show) {
+ assert _phase.ordinal() <= Phase.InstructionSelection.ordinal();
+ _phase = Phase.Schedule;
+
+ // Build the loop tree, fix never-exit loops
+ _start.buildLoopTree(_stop);
+ GlobalCodeMotion.buildCFG(this);
+ if( show )
+ System.out.println(new GraphVisualizer().generateDotOutput(_stop,null,null));
+ return this;
+ }
+
+ // ---------------------------
+ // Local (basic block) scheduler phase, a classic list scheduler
+ public CodeGen localSched() {
+ assert _phase == Phase.Schedule;
+ _phase = Phase.LocalSched;
+ ListScheduler.sched(this);
+ return this;
+ }
+
+
+ // ---------------------------
+ public String reg(Node n) {
+ if( _phase == Phase.RegAlloc ) throw Utils.TODO();
+ return "N"+ n._nid;
+ }
+
+
+ // ---------------------------
+ SB asm(SB sb) { return ASMPrinter.print(sb,this); }
+ String asm() { return asm(new SB()).toString(); }
+
+
+ // Testing shortcuts
+ Node ctrl() { return _stop.ret().ctrl(); }
+ Node expr() { return _stop.ret().expr(); }
+ String print() { return _stop.print(); }
+
+ // Debugging helper
+ @Override public String toString() { return _stop.p(9999); }
+
+ // Debugging helper
+ public Node f(int idx) { return _stop.find(idx); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java b/chapter20/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java
new file mode 100644
index 00000000..12dd9243
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java
@@ -0,0 +1,241 @@
+ package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.IterPeeps.WorkList;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.*;
+import java.util.*;
+
+public abstract class GlobalCodeMotion {
+
+ // Arrange that the existing isCFG() Nodes form a valid CFG. The
+ // Node.use(0) is always a block tail (either IfNode or head of the
+ // following block). There are no unreachable infinite loops.
+ public static void buildCFG( CodeGen code ) {
+ Ary<CFGNode> rpo = new Ary<>(CFGNode.class);
+ _rpo_cfg(null, code._start, code.visit(), rpo);
+ // Reverse in-place
+ for( int i=0; i< rpo.size()>>1; i++ ) {
+ int j = rpo.size()-1-i;
+ CFGNode tmp = rpo.get(i);
+ rpo.set(i, rpo.get(j));
+ rpo.set(j, tmp);
+ }
+ // Set global CFG
+ code._cfg = rpo;
+
+ schedEarly(code);
+ code._visit.clear();
+ schedLate (code);
+ }
+
+ // Post-Order of CFG
+ private static void _rpo_cfg(CFGNode def, Node use, BitSet visit, Ary<CFGNode> rpo) {
+ if( !(use instanceof CFGNode cfg) || visit.get(cfg._nid) )
+ return; // Been there, done that
+ if( def instanceof CallNode && cfg instanceof FunNode )
+ return; // Ignore linked function calls
+ visit.set(cfg._nid);
+ for( Node useuse : cfg._outputs )
+ _rpo_cfg(cfg,useuse,visit,rpo);
+ rpo.add(cfg);
+ }
+
+ // ------------------------------------------------------------------------
+ // Visit all nodes in CFG Reverse Post-Order, essentially defs before uses
+ // (except at loops). Since defs are visited first - and hoisted as early
+ // as possible, when we come to a use we place it just after its deepest
+ // input.
+ private static void schedEarly(CodeGen code) {
+ // Reverse Post-Order on CFG
+ for( CFGNode cfg : code._cfg ) {
+ cfg.loopDepth();
+ for( Node n : cfg._inputs )
+ _schedEarly(n,code._visit );
+ if( cfg instanceof RegionNode )
+ for( Node phi : cfg._outputs )
+ if( phi instanceof PhiNode )
+ _schedEarly(phi,code._visit );
+ }
+ }
+
+ private static void _schedEarly(Node n, BitSet visit) {
+ if( n==null || visit.get(n._nid) ) return; // Been there, done that
+ assert !(n instanceof CFGNode);
+ visit.set(n._nid);
+ // Schedule not-pinned not-CFG inputs before self. Since skipping
+ // Pinned, this never walks the backedge of Phis (and thus spins around
+ // a data-only loop), eventually attempting relying on some pre-visited-
+ // not-post-visited data op with no scheduled control.
+ for( Node def : n._inputs )
+ if( def!=null && !(def instanceof PhiNode) )
+ _schedEarly(def,visit);
+
+ // If not-pinned (e.g. constants, projections, phi) and not-CFG
+ if( !n.isPinned() ) {
+ // Schedule at deepest input
+ CFGNode early = CodeGen.CODE._start; // Maximally early, lowest idepth
+ if( n.in(0) instanceof CFGNode cfg ) early = cfg;
+ for( int i=1; i<n.nIns(); i++ )
+ if( n.in(i)!=null && n.in(i).cfg0().idepth() > early.idepth() )
+ early = n.in(i).cfg0(); // Latest/deepest input
+ n.setDef(0,early);
+ }
+ }
+
+ // ------------------------------------------------------------------------
+ private static void schedLate( CodeGen code ) {
+ CFGNode[] late = new CFGNode[code.UID()];
+ Node[] ns = new Node[code.UID()];
+ // Breadth-first scheduling
+ breadth(code._stop,ns,late);
+
+ // Copy the best placement choice into the control slot
+ for( int i=0; i<late.length; i++ )
+ if( ns[i] != null && !(ns[i] instanceof ProjNode) )
+ ns[i].setDef(0,late[i]);
+ }
+
+ private static void breadth(Node stop, Node[] ns, CFGNode[] late) {
+ // Things on the worklist have some (but perhaps not all) uses done.
+ WorkList<Node> work = new WorkList<>();
+ work.push(stop);
+ Node n;
+ outer:
+ while( (n = work.pop()) != null ) {
+ assert late[n._nid]==null; // No double visit
+ // These I know the late schedule of, and need to set early for loops
+ if( n instanceof CFGNode cfg ) late[n._nid] = cfg.blockHead() ? cfg : cfg.cfg(0);
+ else if( n instanceof PhiNode phi ) late[n._nid] = phi.region();
+ else if( n instanceof ProjNode && n.in(0) instanceof CFGNode cfg ) late[n._nid] = cfg;
+ else {
+
+ // All uses done?
+ for( Node use : n._outputs )
+ if( use!=null && late[use._nid]==null )
+ continue outer; // Nope, await all uses done
+
+ // Loads need their memory inputs' uses also done
+ if( n instanceof LoadNode ld )
+ for( Node memuse : ld.mem()._outputs )
+ if( late[memuse._nid]==null &&
+ // New makes new memory, never crushes load memory
+ !(memuse instanceof NewNode) &&
+ // Load-use directly defines memory
+ (memuse._type instanceof TypeMem ||
+ // Load-use indirectly defines memory
+ (memuse._type instanceof TypeTuple tt && tt._types[ld._alias] instanceof TypeMem)) )
+ continue outer;
+
+ // All uses done, schedule
+ _doSchedLate(n,ns,late);
+ }
+
+ // Walk all inputs and put on worklist, as their last-use might now be done
+ for( Node def : n._inputs )
+ if( def!=null && late[def._nid]==null ) {
+ work.push(def);
+ // if the def has a load use, maybe the load can fire
+ for( Node ld : def._outputs )
+ if( ld instanceof LoadNode && late[ld._nid]==null )
+ work.push(ld);
+ }
+ }
+ }
+
+ private static void _doSchedLate(Node n, Node[] ns, CFGNode[] late) {
+ // Walk uses, gathering the LCA (Least Common Ancestor) of uses
+ CFGNode early = n.in(0) instanceof CFGNode cfg ? cfg : n.in(0).cfg0();
+ assert early != null;
+ CFGNode lca = null;
+ for( Node use : n._outputs )
+ if( use != null )
+ lca = use_block(n,use, late)._idom(lca,null);
+
+ // Loads may need anti-dependencies, raising their LCA
+ if( n instanceof LoadNode load )
+ lca = find_anti_dep(lca,load,early,late);
+
+ // Walk up from the LCA to the early, looking for best place. This is
+ // the lowest execution frequency, approximated by least loop depth and
+ // deepest control flow.
+ CFGNode best = lca;
+ lca = lca.idom(); // Already found best for starting LCA
+ for( ; lca != early.idom(); lca = lca.idom() )
+ if( better(lca,best) )
+ best = lca;
+ assert !(best instanceof IfNode);
+ ns [n._nid] = n;
+ late[n._nid] = best;
+ }
+
+ // Block of use. Normally from late[] schedule, except for Phis, which go
+ // to the matching Region input.
+ private static CFGNode use_block(Node n, Node use, CFGNode[] late) {
+ if( !(use instanceof PhiNode phi) )
+ return late[use._nid];
+ CFGNode found=null;
+ for( int i=1; i<phi.nIns(); i++ )
+ if( phi.in(i)==n )
+ found = phi.region().cfg(i)._idom(found,null);
+
+ assert found!=null;
+ return found;
+ }
+
+
+ // Least loop depth first, then largest idepth
+ private static boolean better( CFGNode lca, CFGNode best ) {
+ return lca.loopDepth() < best.loopDepth() ||
+ (lca.idepth() > best.idepth() || best instanceof IfNode);
+ }
+
+ private static CFGNode find_anti_dep(CFGNode lca, LoadNode load, CFGNode early, CFGNode[] late) {
+ // We could skip final-field loads here.
+ // Walk LCA->early, flagging Load's block location choices
+ for( CFGNode cfg=lca; early!=null && cfg!=early.idom(); cfg = cfg.idom() )
+ cfg._anti = load._nid;
+ // Walk load->mem uses, looking for Stores causing an anti-dep
+ for( Node mem : load.mem()._outputs ) {
+ switch( mem ) {
+ case StoreNode st:
+ assert late[st._nid]!=null;
+ lca = anti_dep(load,late[st._nid],st.cfg0(),lca,st);
+ break;
+ case CallNode st:
+ assert late[st._nid]!=null;
+ lca = anti_dep(load,late[st._nid],st.cfg0(),lca,st);
+ break;
+ case PhiNode phi:
+ // Repeat anti-dep for matching Phi inputs.
+ // No anti-dep edges but may raise the LCA.
+ for( int i=1; i<phi.nIns(); i++ )
+ if( phi.in(i)==load.mem() )
+ lca = anti_dep(load,phi.region().cfg(i),load.mem().cfg0(),lca,null);
+ break;
+ case NewNode st: break;
+ case LoadNode ld: break; // Loads do not cause anti-deps on other loads
+ case ReturnNode ret: break; // Load must already be ahead of Return
+ case MemMergeNode ret: break; // Mem uses now on ScopeMin
+ case NeverNode never: break;
+ default: throw Utils.TODO();
+ }
+ }
+ return lca;
+ }
+
+ //
+ private static CFGNode anti_dep( LoadNode load, CFGNode stblk, CFGNode defblk, CFGNode lca, Node st ) {
+ // Walk store blocks "reach" from its scheduled location to its earliest
+ for( ; stblk != defblk.idom(); stblk = stblk.idom() ) {
+ // Store and Load overlap, need anti-dependence
+ if( stblk._anti==load._nid ) {
+ lca = stblk._idom(lca,null); // Raise Loads LCA
+ if( lca == stblk && st != null && st._inputs.find(load) == -1 ) // And if something moved,
+ st.addDef(load); // Add anti-dep as well
+ return lca; // Cap this stores' anti-dep to here
+ }
+ }
+ return lca;
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/GraphVisualizer.java b/chapter20/src/main/java/com/seaofnodes/simple/GraphVisualizer.java
new file mode 100644
index 00000000..30e25916
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/GraphVisualizer.java
@@ -0,0 +1,288 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+
+import java.util.*;
+
+import static com.seaofnodes.simple.Utils.TODO;
+
+/**
+ * Simple visualizer that outputs GraphViz dot format.
+ * The dot output must be saved to a file and run manually via dot to generate the SVG output.
+ * Currently, this is done manually.
+ */
+public class GraphVisualizer {
+
+ /**
+ * If set to true we put the control nodes in a separate cluster from
+ * data nodes.
+ */
+ boolean _separateControlCluster = false;
+
+ public GraphVisualizer(boolean separateControlCluster) { this._separateControlCluster = separateControlCluster; }
+ public GraphVisualizer() { this(false); }
+
+ public String generateDotOutput(Parser parse) { return generateDotOutput(parse._code._stop,parse._scope,parse._xScopes); }
+ public String generateDotOutput(StopNode stop, Node scope, Stack<ScopeNode> xScopes) {
+
+ // Since the graph has cycles, we need to create a flat list of all the
+ // nodes in the graph.
+ Collection<Node> all = findAll(xScopes, stop, scope);
+ StringBuilder sb = new StringBuilder();
+ sb.append("digraph chapter18 {\n");
+ sb.append("/*\n");
+ sb.append(stop._src);
+ sb.append("\n*/\n");
+
+ // To keep the Scopes below the graph and pointing up into the graph we
+ // need to group the Nodes in a subgraph cluster, and the scopes into a
+ // different subgraph cluster. THEN we can draw edges between the
+ // scopes and nodes. If we try to cross subgraph cluster borders while
+ // still making the subgraphs DOT gets confused.
+ sb.append("\trankdir=BT;\n"); // Force Nodes before Scopes
+
+ // CNC - turned off Apr/8/2024, gives more flex in the layout and
+ // removes some of the more ludicrous layout choices.
+ // Preserve node input order
+ //sb.append("\tordering=\"in\";\n");
+
+ // Merge multiple edges hitting the same node. Makes common shared
+ // nodes much prettier to look at.
+ sb.append("\tconcentrate=\"true\";\n");
+
+ // Force nested scopes to order
+ sb.append("\tcompound=\"true\";\n");
+
+ // Just the Nodes first, in a cluster no edges
+ nodes(sb, all);
+
+ // Now the scopes, in a cluster no edges
+ if( xScopes != null )
+ for( ScopeNode xscope : xScopes )
+ if( !xscope.isDead() )
+ scope( sb, xscope );
+
+ // Walk the Node edges
+ nodeEdges(sb, all);
+
+ // Walk the active Scope edges
+ if( xScopes != null )
+ for( ScopeNode xscope : xScopes )
+ if( !xscope.isDead() )
+ scopeEdges( sb, xscope );
+
+ sb.append("}\n");
+ return sb.toString();
+ }
+
+ private void nodesByCluster(StringBuilder sb, boolean doCtrl, Collection<Node> all) {
+ if (!_separateControlCluster && doCtrl) // all nodes in 1 cluster
+ return;
+ // Just the Nodes first, in a cluster no edges
+ sb.append(doCtrl ? "\tsubgraph cluster_Controls {\n" : "\tsubgraph cluster_Nodes {\n"); // Magic "cluster_" in the subgraph name
+ for (Node n : all) {
+ if (n instanceof ProjNode || n instanceof CProjNode || n instanceof MemMergeNode || n==Parser.XCTRL)
+ continue; // Do not emit, rolled into MultiNode or Scope cluster already
+ if( _separateControlCluster && doCtrl && !(n instanceof CFGNode) ) continue;
+ if( _separateControlCluster && !doCtrl && (n instanceof CFGNode) ) continue;
+ sb.append("\t\t").append(n.uniqueName()).append(" [ ");
+ String lab = n.glabel();
+ if (n instanceof MultiNode) {
+ // Make a box with the MultiNode on top, and all the projections on the bottom
+ sb.append("shape=plaintext label=<\n");
+ sb.append("\t\t\t<TABLE BORDER=\"0\" CELLBORDER=\"1\" CELLSPACING=\"0\" CELLPADDING=\"4\">\n");
+ sb.append("\t\t\t<TR><TD BGCOLOR=\"yellow\">").append(lab).append("</TD></TR>\n");
+ sb.append("\t\t\t<TR>");
+ boolean doProjTable = false;
+ n._outputs.sort((x,y) -> x instanceof ProjNode xp && y instanceof ProjNode yp ? (xp._idx - yp._idx) : (x._nid - y._nid));
+ for (Node use : n._outputs) {
+ if (use instanceof ProjNode proj) {
+ if (!doProjTable) {
+ doProjTable = true;
+ sb.append("<TD>").append("\n");
+ sb.append("\t\t\t\t<TABLE BORDER=\"0\" CELLBORDER=\"1\" CELLSPACING=\"0\">").append("\n");
+ sb.append("\t\t\t\t<TR>");
+ }
+ sb.append("<TD PORT=\"p").append(proj._idx).append("\">").append(proj.glabel()).append("</TD>");
+ }
+ if (use instanceof CProjNode proj) {
+ if (!doProjTable) {
+ doProjTable = true;
+ sb.append("<TD>").append("\n");
+ sb.append("\t\t\t\t<TABLE BORDER=\"0\" CELLBORDER=\"1\" CELLSPACING=\"0\">").append("\n");
+ sb.append("\t\t\t\t<TR>");
+ }
+ sb.append("<TD PORT=\"p").append(proj._idx).append("\" BGCOLOR=\"yellow\">").append(proj.glabel()).append("</TD>");
+ }
+ }
+ if (doProjTable) {
+ sb.append("</TR>").append("\n");
+ sb.append("\t\t\t\t</TABLE>").append("\n");
+ sb.append("\t\t\t</TD>");
+ }
+ sb.append("</TR>\n");
+ sb.append("\t\t\t</TABLE>>\n\t\t");
+
+ } else {
+ // control nodes have box shape
+ // other nodes are ellipses, i.e. default shape
+ if( n instanceof CFGNode ) sb.append("shape=box style=filled fillcolor=yellow ");
+ else if (n instanceof PhiNode) sb.append("style=filled fillcolor=lightyellow ");
+ sb.append("label=\"").append(lab).append("\" ");
+ }
+ sb.append("];\n");
+ }
+ if (!_separateControlCluster) {
+ // Force Region & Phis to line up
+ for (Node n : all) {
+ if (n instanceof RegionNode region) {
+ sb.append("\t\t{ rank=same; ");
+ sb.append(region.uniqueName()).append(";");
+ for (Node phi : region._outputs)
+ if (phi instanceof PhiNode) sb.append(phi.uniqueName()).append(";");
+ sb.append("}\n");
+ }
+ }
+ }
+ sb.append("\t}\n"); // End Node cluster
+ }
+
+ private void nodes(StringBuilder sb, Collection<Node> all) {
+ nodesByCluster(sb, true, all);
+ nodesByCluster(sb, false, all);
+ }
+
+ // Build a nested scope display, walking the _prev edge
+ private void scope( StringBuilder sb, ScopeNode scope ) {
+ sb.append("\tnode [shape=plaintext];\n");
+ int last = scope.nIns();
+ int max = scope._lexSize.size();
+ for( int i = 0; i < max; i++ ) {
+ int level = max-i-1;
+ String scopeName = makeScopeName(scope, level);
+ sb.append("\tsubgraph cluster_").append(scopeName).append(" {\n"); // Magic "cluster_" in the subgraph name
+ // Special for memory ScopeMinNode
+ if( level==0 ) {
+ MemMergeNode n = scope.mem();
+ sb.append("\t\t").append(n.uniqueName()).append(" [label=\"").append(n.glabel()).append("\"];\n");
+ }
+ sb.append("\t\t").append(scopeName).append(" [label=<\n");
+ sb.append("\t\t\t<TABLE BORDER=\"0\" CELLBORDER=\"1\" CELLSPACING=\"0\">\n");
+ // Add the scope level
+ sb.append("\t\t\t<TR><TD BGCOLOR=\"cyan\">").append(level).append("</TD>");
+ int lexStart=scope._lexSize.at(level);
+ for( int j=lexStart; j<last; j++ ) {
+ var v = scope._vars.at(j);
+ sb.append("<TD PORT=\"").append(makePortName(scopeName, v._name)).append("\">").append(v._name).append("</TD>");
+ }
+ last = lexStart;
+ sb.append("</TR>\n");
+ sb.append("\t\t\t</TABLE>>];\n");
+ }
+ // Scope clusters nest, so the graphics shows the nested scopes, so
+ // they are not closed as they are printed; so they just keep nesting.
+ // We close them all at once here.
+ sb.append( "\t}\n".repeat( max ) ); // End all Scope clusters
+ }
+
+ private String makeScopeName(ScopeNode sn, int level) { return sn.uniqueName() + "_" + level; }
+ private String makePortName(String scopeName, String varName) { return scopeName + "_" + varName; }
+
+ // Walk the node edges
+ private void nodeEdges(StringBuilder sb, Collection<Node> all) {
+ // All them edge labels
+ sb.append("\tedge [ fontname=Helvetica, fontsize=8 ];\n");
+ for( Node n : all ) {
+ // Do not display the Constant->Start edge;
+ // ProjNodes handled by Multi;
+ // ScopeNodes are done separately
+ if( n instanceof ConstantNode || n instanceof ProjNode || n instanceof CProjNode || n instanceof ScopeNode || n==Parser.XCTRL )
+ continue;
+ for( int i=0; i<n.nIns(); i++ ) {
+ Node def = n.in(i);
+ if( n instanceof PhiNode && def instanceof RegionNode ) {
+ // Draw a dotted use->def edge from Phi to Region.
+ sb.append('\t').append(n.uniqueName());
+ sb.append(" -> ");
+ sb.append(def.uniqueName());
+ sb.append(" [style=dotted taillabel=").append(i).append("];\n");
+ } else if( def != null ) {
+ // Most edges land here use->def
+ sb.append('\t').append(n.uniqueName()).append(" -> ");
+ if( def instanceof CProjNode proj ) {
+ String mname = proj.ctrl().uniqueName();
+ sb.append(mname).append(":p").append(proj._idx);
+ } else if( def instanceof ProjNode proj ) {
+ String mname = proj.in(0).uniqueName();
+ sb.append(mname).append(":p").append(proj._idx);
+ } else sb.append(def.uniqueName());
+ // Number edges, so we can see how they track
+ sb.append("[taillabel=").append(i);
+ // The edge from New to ctrl is just for anchoring the New
+ if ( n instanceof NewNode )
+ sb.append(" color=green");
+ // control edges are colored red
+ else if( def instanceof CFGNode )
+ sb.append(" color=red");
+ else if( def.isMem() )
+ sb.append(" color=blue");
+ // Backedges do not add a ranking constraint
+ if( i==2 && (n instanceof PhiNode || n instanceof LoopNode) )
+ sb.append(" constraint=false");
+ sb.append("];\n");
+ }
+ }
+ }
+ }
+
+ // Walk the scope edges
+ private void scopeEdges( StringBuilder sb, ScopeNode scope ) {
+ sb.append("\tedge [style=dashed color=cornflowerblue];\n");
+ int level=0;
+ for( var v : scope._vars ) {
+ Node def = scope.in(v._idx);
+ while( def instanceof ScopeNode lazy )
+ def = lazy.in(v._idx);
+ if( def==null ) continue;
+ while( level < scope._lexSize.size() && v._idx >= scope._lexSize.at(level) )
+ level++;
+ String scopeName = makeScopeName(scope, level-1);
+ sb.append("\t")
+ .append(scopeName).append(":")
+ .append('"').append(makePortName(scopeName, v._name)).append('"') // wrap port name with quotes because $ctrl is not valid unquoted
+ .append(" -> ");
+ if( def instanceof CProjNode proj ) {
+ sb.append(def.in(0).uniqueName()).append(":p").append(proj._idx);
+ } else if( def instanceof ProjNode proj ) {
+ sb.append(def.in(0).uniqueName()).append(":p").append(proj._idx);
+ } else sb.append(def.uniqueName());
+ sb.append(";\n");
+ }
+ }
+
+ /**
+ * Finds all nodes in the graph.
+ */
+ public static Collection<Node> findAll(Stack<ScopeNode> ss, Node... ns) {
+ final HashMap<Integer, Node> all = new HashMap<>();
+ for( Node n : ns )
+ walk(all, n);
+ if( ss != null )
+ for( Node n : ss )
+ walk(all, n);
+ return all.values();
+ }
+
+ /**
+ * Walk a subgraph and populate distinct nodes in the all list.
+ */
+ private static void walk(HashMap<Integer,Node> all, Node n) {
+ if(n == null ) return;
+ if (all.get(n._nid) != null) return; // Been there, done that
+ all.put(n._nid, n);
+ for (Node c : n._inputs)
+ walk(all, c);
+ for( Node c : n._outputs )
+ walk(all, c);
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/IRPrinter.java b/chapter20/src/main/java/com/seaofnodes/simple/IRPrinter.java
new file mode 100644
index 00000000..3cddacfd
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/IRPrinter.java
@@ -0,0 +1,279 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeFunPtr;
+import java.util.ArrayList;
+import java.util.BitSet;
+import java.util.HashMap;
+
+public abstract class IRPrinter {
+
+ // Print a node on 1 line, columnar aligned, as:
+ // NNID NNAME DDEF DDEF [[ UUSE UUSE ]] TYPE
+ // 1234 sssss 1234 1234 1234 1234 1234 1234 tttttt
+ public static SB printLine( Node n, SB sb ) {
+ sb.p("%4d %-7.7s ".formatted(n._nid,n.label()));
+ if( n._inputs==null )
+ return sb.p("DEAD\n");
+ for( Node def : n._inputs )
+ sb.p(def==null ? "____" : "%4d".formatted(def._nid))
+ // Lazy Phi indicator
+ .p(n instanceof MemMergeNode && def instanceof MemMergeNode ? "^" : " ");
+ for( int i = n._inputs.size(); i<4; i++ )
+ sb.p(" ");
+ sb.p(" [[ ");
+ for( Node use : n._outputs )
+ sb.p(use==null ? "____ " : "%4d ".formatted(use._nid));
+ int lim = 6 - Math.max(n._inputs.size(),4);
+ for( int i = n._outputs.size(); i<lim; i++ )
+ sb.p(" ");
+ sb.p(" ]] ");
+ if( n._type!= null ) sb.p(n._type.str());
+ return sb.p("\n");
+ }
+
+
+ public static String prettyPrint(Node node, int depth) {
+ return CodeGen.CODE._phase.ordinal() > CodeGen.Phase.Schedule.ordinal()
+ ? _prettyPrintScheduled( node, depth )
+ : _prettyPrint( node, depth );
+ }
+
+ // Another bulk pretty-printer. Makes more effort at basic-block grouping.
+ private static String _prettyPrint( Node node, int depth ) {
+ // First, a Breadth First Search at a fixed depth.
+ BFS bfs = new BFS(node,depth);
+ // Convert just that set to a post-order
+ ArrayList<Node> rpos = new ArrayList<>();
+ BitSet visit = new BitSet();
+ for( int i=bfs._lim; i< bfs._bfs.size(); i++ )
+ postOrd( bfs._bfs.get(i), null, rpos, visit, bfs._bs);
+ // Reverse the post-order walk
+ SB sb = new SB();
+ boolean gap=false;
+ for( int i=rpos.size()-1; i>=0; i-- ) {
+ Node n = rpos.get(i);
+ if( n instanceof CFGNode || n.isMultiHead() ) {
+ if( !gap ) sb.p("\n"); // Blank before multihead
+ if( n instanceof FunNode fun )
+ fun.sig().print(sb.p("--- ").p(fun._name==null ? "" : fun._name).p(" "),false).p("----------------------\n");
+ printLine( n, sb ); // Print head
+ while( --i >= 0 ) {
+ Node t = rpos.get(i);
+ if( !t.isMultiTail() ) { i++; break; }
+ printLine( t, sb );
+ }
+ if( n instanceof ReturnNode ret ) {
+ FunNode fun = ret.fun();
+ fun.sig().print(sb.p("--- ").p(fun._name==null ? "" : fun._name).p(" "),false).p("----------------------\n");
+ }
+ if( !(n instanceof CallNode) ) {
+ sb.p("\n"); // Blank after multitail
+ gap = true;
+ }
+ } else {
+ printLine( n, sb );
+ gap = false;
+ }
+ }
+ return sb.toString();
+ }
+
+ private static void postOrd(Node n, Node prior, ArrayList<Node> rpos, BitSet visit, BitSet bfs) {
+ if( !bfs.get(n._nid) )
+ return; // Not in the BFS visit
+ if( n instanceof FunNode && !(prior instanceof StartNode) )
+ return; // Only visit Fun from Start
+ if( visit.get(n._nid) ) return; // Already post-order walked
+ visit.set(n._nid);
+ // First walk the CFG, then everything
+ if( n instanceof CFGNode ) {
+ for( Node use : n._outputs )
+ // Follow CFG, not across call/function borders, and not around backedges
+ if( use instanceof CFGNode && !(n instanceof CallNode && use instanceof FunNode) &&
+ use.nOuts() >= 1 && !(use._outputs.get(0) instanceof LoopNode) )
+ postOrd(use, n, rpos,visit,bfs);
+ for( Node use : n._outputs )
+ // Follow CFG, not across call/function borders
+ if( use instanceof CFGNode && !(n instanceof CallNode && use instanceof FunNode) )
+ postOrd(use,n,rpos,visit,bfs);
+ }
+ // Follow all outputs
+ for( Node use : n._outputs )
+ if( use != null &&
+ !(n instanceof CallNode && use instanceof FunNode) &&
+ (n instanceof FunNode || !(use instanceof ParmNode)) )
+ postOrd(use, n, rpos,visit,bfs);
+ // Post-order
+ rpos.add(n);
+ }
+
+ // Breadth-first search, broken out in a class to keep in more independent.
+ // Maintains a root-set of Nodes at the limit (or past by 1 if MultiHead).
+ public static class BFS {
+ // A breadth first search, plus MultiHeads for any MultiTails
+ public final ArrayList<Node> _bfs;
+ public final BitSet _bs; // Visited members by node id
+ public final int _depth; // Depth limit
+ public final int _lim; // From here to _bfs._len can be roots for a reverse search
+ public BFS( Node base, int d ) {
+ _depth = d;
+ _bfs = new ArrayList<>();
+ _bs = new BitSet();
+
+ add(base); // Prime the pump
+ int idx=0, lim=1; // Limit is where depth counter changes
+ while( idx < _bfs.size() ) { // Ran out of nodes below depth
+ Node n = _bfs.get(idx++);
+ for( Node def : n._inputs )
+ if( def!=null && !_bs.get(def._nid) )
+ add(def);
+ if( idx==lim ) { // Depth counter changes at limit
+ if( --d < 0 )
+ break; // Ran out of depth
+ lim = _bfs.size(); // New depth limit
+ }
+ }
+ // Toss things past the limit except multi-heads
+ while( idx < _bfs.size() ) {
+ Node n = _bfs.get(idx);
+ if( n.isMultiHead() ) idx++;
+ else del(idx);
+ }
+ // Root set is any node with no inputs in the visited set
+ lim = _bfs.size();
+ for( int i=_bfs.size()-1; i>=0; i-- )
+ if( !any_visited(_bfs.get(i)) )
+ swap( i,--lim);
+ _lim = lim;
+ }
+ void swap( int x, int y ) {
+ if( x==y ) return;
+ Node tx = _bfs.get(x);
+ Node ty = _bfs.get(y);
+ _bfs.set(x,ty);
+ _bfs.set(y,tx);
+ }
+ void add(Node n) {
+ _bfs.add(n);
+ _bs.set(n._nid);
+ }
+ void del(int idx) {
+ _bs.clear(_bfs.get(idx)._nid);
+ Utils.del(_bfs, idx);
+ }
+ boolean any_visited( Node n ) {
+ for( Node def : n._inputs )
+ if( def!=null && _bs.get(def._nid) )
+ return true;
+ return false;
+ }
+ }
+
+ // Bulk pretty printer, knowing scheduling information is available
+ private static String _prettyPrintScheduled( Node node, int depth ) {
+ // Backwards DFS walk to depth.
+ HashMap<Integer,Integer> ds = new HashMap<>();
+ Ary<Node> ns = new Ary<>(Node.class);
+ _walk(ds,ns,node,depth);
+ // Remove data projections, these are force-printed behind their multinode head
+ for( int i=0; i<ns.size(); i++ ) {
+ if( ns.get(i) instanceof ProjNode proj && !(proj.in(0) instanceof CFGNode) ) {
+ ns.del(i--);
+ ds.remove(proj._nid);
+ }
+ }
+ // Print by block with least idepth
+ SB sb = new SB();
+ Ary<Node> bns = new Ary<>(Node.class);
+ while( !ds.isEmpty() ) {
+ CFGNode blk = null;
+ for( Node n : ns ) {
+ CFGNode cfg = n instanceof CFGNode cfg0 && cfg0.blockHead() ? cfg0 : n.cfg0();
+ if( blk==null || cfg.idepth() < blk.idepth() )
+ blk = cfg;
+ }
+ Integer d = ds.remove(blk._nid);
+ ns.del(ns.find(blk));
+
+ // Print block header
+ sb.p("%-13.13s".formatted(label(blk)+":"));
+ sb.p( " ".repeat(4) ).p(" [[ ");
+ if( blk instanceof StartNode ) ;
+ else if( blk instanceof RegionNode || blk instanceof StopNode )
+ for( int i=(blk instanceof StopNode ? 3 : 1); i<blk.nIns(); i++ )
+ label(sb,blk.cfg(i));
+ else
+ label(sb,blk.cfg(0));
+ sb.p(" ]] \n");
+ printLine(blk,sb);
+
+ // Collect block contents that are in the depth limit
+ bns.clear();
+ int xd = Integer.MAX_VALUE;
+ for( Node use : blk._outputs ) {
+ Integer i = ds.get(use._nid);
+ if( i!=null && !(use instanceof CFGNode cfg && cfg.blockHead()) ) {
+ if( bns.find(use)==-1 )
+ bns.add(use);
+ xd = Math.min(xd,i);
+ }
+ }
+ // Print Phis up front, if any
+ for( int i=0; i<bns.size(); i++ )
+ if( bns.get(i) instanceof PhiNode phi )
+ printLine( phi, sb,bns,i--,ds,ns);
+
+ // Print block contents in depth order, bumping depth until whole block printed
+ for( ; !bns.isEmpty(); xd++ )
+ for( int i=0; i<bns.size(); i++ ) {
+ Node n = bns.get(i);
+ if( ds.get(n._nid)==xd ) {
+ printLine( n, sb, bns, i--, ds,ns );
+ if( n instanceof MultiNode && !(n instanceof CFGNode) ) {
+ for( Node use : n._outputs ) {
+ printLine(use,sb,bns,bns.indexOf(use),ds,ns);
+ }
+ }
+ }
+ }
+ sb.p("\n");
+ }
+ return sb.toString();
+ }
+
+ private static void _walk( HashMap<Integer,Integer> ds, Ary<Node> ns, Node node, int d ) {
+ Integer nd = ds.get(node._nid);
+ if( nd!=null && d <= nd ) return; // Been there, done that
+ Integer old = ds.put(node._nid,d) ;
+ if( old == null )
+ ns.add(node);
+ if( d == 0 ) return; // Depth cutoff
+ for( Node def : node._inputs )
+ if( def != null &&
+ !(node instanceof LoopNode loop && loop.back()==def) &&
+ // Don't walk into or out of functions
+ !(node instanceof CallEndNode && def instanceof ReturnNode) &&
+ !(node instanceof FunNode && def instanceof CallNode) &&
+ !(node instanceof ParmNode && !(def instanceof FunNode))
+ )
+ _walk(ds,ns,def,d-1);
+ }
+
+ static String label( CFGNode blk ) {
+ if( blk instanceof StartNode ) return "START";
+ return (blk instanceof LoopNode ? "LOOP" : "L")+blk._nid;
+ }
+ static void label( SB sb, CFGNode blk ) {
+ if( !blk.blockHead() ) blk = blk.cfg(0);
+ sb.p( "%-9.9s ".formatted( label( blk ) ) );
+ }
+ static void printLine( Node n, SB sb, Ary<Node> bns, int i, HashMap<Integer,Integer> ds, Ary<Node> ns ) {
+ printLine( n, sb );
+ if( i != -1 ) bns.del(i);
+ ds.remove(n._nid);
+ int idx = ns.find(n);
+ if( idx!=-1 ) ns.del(idx);
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/IterPeeps.java b/chapter20/src/main/java/com/seaofnodes/simple/IterPeeps.java
new file mode 100644
index 00000000..265e0b21
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/IterPeeps.java
@@ -0,0 +1,196 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+
+import java.util.Arrays;
+import java.util.BitSet;
+import java.util.Random;
+
+/**
+ * The IterPeeps runs after parsing. It iterates the peepholes to a fixed point
+ * so that no more peepholes apply. This should be linear because peepholes rarely
+ * (never?) increase code size. The graph should monotonically reduce in some
+ * dimension, which is usually size. It might also reduce in e.g. number of
+ * MulNodes or Load/Store nodes, swapping out more "expensive" Nodes for cheaper
+ * ones.
+ * <br>
+ * The theoretical overall worklist is mindless just grabbing the next thing and
+ * doing it. If the graph changes, put the neighbors on the worklist.
+ * <br>
+ * Lather, Rinse, Repeat until the worklist runs dry.
+ * <p>
+ * The main issues we have to deal with:
+ *
+ * <ul>
+ * <li>Nodes have uses; replacing some set of Nodes with another requires more graph
+ * reworking. Not rocket science, but it can be fiddly. Its helpful to have a
+ * small set of graph munging utilities, and the strong invariant that the graph
+ * is stable and correct between peepholes. In our case `Node.subsume` does
+ * most of the munging, building on our prior stable Node utilities.</li>
+ *
+ * <li>Changing a Node also changes the graph "neighborhood". The neighbors need to
+ * be checked to see if THEY can also peephole, and so on. After any peephole
+ * or graph update we put a Nodes uses and defs on the worklist.</li>
+ *
+ * <li>Our strong invariant is that for all Nodes, either they are on the worklist
+ * OR no peephole applies. This invariant is easy to check, although expensive.
+ * Basically the normal "iterate peepholes to a fixed point" is linear, and this
+ * check is linear at each peephole step... so quadratic overall. Its a useful
+ * assert, but one we can disable once the overall algorithm is stable - and
+ * then turn it back on again when some new set of peepholes is misbehaving.
+ * The code for this is turned on in `IterPeeps.iterate` as `assert
+ * progressOnList(stop);`</li>
+ * </ul>
+ */
+public class IterPeeps {
+
+ private final WorkList<Node> _work;
+
+ IterPeeps( long seed ) { _work = new WorkList<>(seed); }
+
+ public <N extends Node> N add( N n ) { return (N)_work.push(n); }
+
+ public void addAll( Ary<Node> ary ) { _work.addAll(ary); }
+
+ /**
+ * Iterate peepholes to a fixed point
+ */
+ public void iterate( CodeGen code ) {
+ assert progressOnList(code);
+ int cnt=0;
+
+ Node n;
+ while( (n=_work.pop()) != null ) {
+ if( n.isDead() ) continue;
+ cnt++; // Useful for debugging, searching which peephole broke things
+ Node x = n.peepholeOpt();
+ if( x != null ) {
+ if( x.isDead() ) continue;
+ // peepholeOpt can return brand-new nodes, needing an initial type set
+ if( x._type==null ) x.setType(x.compute());
+ // Changes require neighbors onto the worklist
+ if( x != n || !(x instanceof ConstantNode) ) {
+ // All outputs of n (changing node) not x (prior existing node).
+ for( Node z : n._outputs ) _work.push(z);
+ // Everybody gets a free "go again" in case they didn't get
+ // made in their final form.
+ _work.push(x);
+ // If the result is not self, revisit all inputs (because
+ // there's a new user), and replace in the graph.
+ if( x != n ) {
+ for( Node z : n. _inputs ) _work.push(z);
+ n.subsume(x);
+ }
+ }
+ // If there are distant neighbors, move to worklist
+ n.moveDepsToWorklist();
+ JSViewer.show(); // Show again
+ assert progressOnList(code); // Very expensive assert
+ }
+ if( n.isUnused() && !(n instanceof StopNode) )
+ n.kill(); // Just plain dead
+ }
+
+ }
+
+ // Visit ALL nodes and confirm the invariant:
+ // Either you are on the _work worklist OR running `iter()` makes no progress.
+
+ // This invariant ensures that no progress is missed, i.e., when the
+ // worklist is empty we have indeed done all that can be done. To help
+ // with debugging, the {@code assert} is broken out in a place where it is easy to
+ // stop if a change is found.
+
+ // Also, the normal usage of `iter()` may attempt peepholes with distance
+ // neighbors and these should fail, but will then try to add dependencies
+ // {@link #Node.addDep} which is a side effect in an assert. The {@link
+ // #midAssert} is used to stop this side effect.
+ private boolean progressOnList(CodeGen code) {
+ code._midAssert = true;
+ Node changed = code._stop.walk( n -> {
+ Node m = n;
+ if( n.compute().isa(n._type) && (!n.iskeep() || n._nid<=6) ) { // Types must be forwards, even if on worklist
+ if( _work.on(n) ) return null;
+ m = n.peepholeOpt();
+ if( m==null ) return null;
+ }
+ System.err.println("BREAK HERE FOR BUG");
+ return m;
+ });
+ code._midAssert = false;
+ return changed==null;
+ }
+
+ /**
+ * Classic WorkList, with a fast add/remove, dup removal, random pull.
+ * The Node's nid is used to check membership in the worklist.
+ */
+ public static class WorkList<E extends Node> {
+
+ private Node[] _es;
+ private int _len;
+ private final BitSet _on; // Bit set if Node._nid is on WorkList
+ private final Random _R; // For randomizing pull from the WorkList
+ private final long _seed;
+
+ /* Useful stat - how many nodes are processed in the post parse iterative opt */
+ private long _totalWork = 0;
+
+ WorkList() { this(123); }
+ WorkList(long seed) {
+ _es = new Node[1];
+ _len=0;
+ _on = new BitSet();
+ _seed = seed;
+ _R = new Random();
+ _R.setSeed(_seed);
+ }
+
+ /**
+ * Pushes a Node on the WorkList, ensuring no duplicates
+ * If Node is null it will not be added.
+ */
+ public E push( E x ) {
+ if( x==null ) return null;
+ int idx = x._nid;
+ if( !_on.get(idx) ) {
+ _on.set(idx);
+ if( _len==_es.length )
+ _es = Arrays.copyOf(_es,_len<<1);
+ _es[_len++] = x;
+ _totalWork++;
+ }
+ return x;
+ }
+
+ public void addAll( Ary<E> ary ) {
+ for( E n : ary )
+ push(n);
+ }
+
+ /**
+ * True if Node is on the WorkList
+ */
+ boolean on( E x ) { return _on.get(x._nid); }
+ boolean isEmpty() { return _len==0; }
+
+ /**
+ * Removes a random Node from the WorkList; null if WorkList is empty
+ */
+ E pop() {
+ if( _len == 0 ) return null;
+ int idx = _R.nextInt(_len);
+ E x = (E)_es[idx];
+ _es[idx] = _es[--_len]; // Compress array
+ _on.clear(x._nid);
+ return x;
+ }
+
+ public void clear() {
+ _len = 0;
+ _on.clear();
+ _R.setSeed(_seed);
+ _totalWork = 0;
+ }
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/JSViewer.java b/chapter20/src/main/java/com/seaofnodes/simple/JSViewer.java
new file mode 100644
index 00000000..fcb0c28a
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/JSViewer.java
@@ -0,0 +1,402 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.*;
+import java.io.IOException;
+import java.util.Stack;
+import java.nio.file.Paths;
+import java.util.Collection;
+import static com.seaofnodes.simple.CodeGen.CODE;
+
+public class JSViewer implements AutoCloseable {
+ // Display programs in an endless loop
+ public static void main( String[] args ) throws Exception {
+ try(var js = new JSViewer()) {
+ js.run();
+ }
+ }
+
+ static boolean SHOW;
+
+ // WebSocket to the browser for display
+ static SimpleWebSocket SERVER;
+
+ static int N; // Dot frames
+
+ JSViewer() throws Exception {
+ // Launch server; handshake
+ SERVER = new SimpleWebSocket(Paths.get("docs/index.html").toUri(),12345) ;
+ }
+
+ void run( ) throws Exception {
+ SERVER.put("!");
+ while( true ) {
+ String src = SERVER.get();
+ switch( src ) {
+ case null: return;
+ case "null": return;
+ case "+": break; // Client requests more frames, but we send them all anyway
+ default:
+ System.out.println(src);
+ try {
+ N=0;
+ // Use parser scope, xscope when building views
+ CodeGen code = new CodeGen(src);
+ SHOW = true;
+ show();
+ // Parse program, generating views at every parse point
+ code.parse();
+ // No longer user parse internal state when building views
+ code.opto();
+
+ // Catch and ignore Parser errors
+ } catch(RuntimeException re) {
+ System.err.println(re);
+ } finally {
+ SHOW = false;
+ SERVER.put("#"); // Final frame
+ }
+ break;
+ }
+ }
+ }
+
+ @Override public void close() throws IOException {
+ SERVER.close();
+ SERVER=null;
+ }
+
+ public static void show() { if( SERVER!=null && SHOW ) _show(); }
+ private static void _show() {
+ // Skip util we at least get the Parse object made
+ if( CODE._phase==null || CODE._phase.ordinal() < CodeGen.Phase.Parse.ordinal() )
+ return;
+ boolean midParse = CODE._phase == CodeGen.Phase.Parse;
+ Stack<ScopeNode> xScopes = midParse ? CODE.P._xScopes : null;
+
+ Collection<Node> all = GraphVisualizer.findAll(xScopes, CODE._stop, midParse ? CODE.P._scope: null);
+ SB sb = new SB();
+ sb.p("digraph view_").p(N++).p(" {\n").ii();
+ if( midParse )
+ sb.i().p("// POS: ").p(CODE.P.pos()).nl();
+
+ // To keep the Scopes below the graph and pointing up into the graph we
+ // need to group the Nodes in a subgraph cluster, and the scopes into a
+ // different subgraph cluster. THEN we can draw edges between the
+ // scopes and nodes. If we try to cross subgraph cluster borders while
+ // still making the subgraphs DOT gets confused.
+ sb.i().p("rankdir=BT;\n"); // Force Nodes before Scopes
+
+ // CNC - turned off Apr/8/2024, gives more flex in the layout and
+ // removes some of the more ludicrous layout choices.
+ // Preserve node input order
+ //sb.append("ordering=\"in\";\n");
+
+ // Merge multiple edges hitting the same node. Makes common shared
+ // nodes much prettier to look at.
+ sb.i().p("concentrate=\"true\";\n");
+
+ // Force nested scopes to order
+ sb.i().p("compound=\"true\";\n");
+
+ // Just the Nodes first, in a cluster no edges
+ nodes(sb, all);
+
+ // Now the scopes, in a cluster no edges
+ if( midParse )
+ for( ScopeNode xscope : xScopes )
+ if( !xscope.isDead() )
+ scope( sb, xscope );
+
+ // Walk the Node edges
+ nodeEdges(sb, midParse && !xScopes.empty() ? xScopes.peek() : null, all);
+
+ // Walk the active Scope edges
+ if( midParse )
+ for( ScopeNode xscope : xScopes )
+ if( !xscope.isDead() )
+ scopeEdges( sb, xscope );
+
+
+ sb.p("}\n").di();
+ // Tell client another DOT frame
+ String dot = sb.toString();
+ System.out.println(dot);
+ try {
+ SERVER.put(dot);
+ } catch( IOException ioe ) {
+ try { SERVER.close();} catch( IOException ignored ){}
+ }
+ }
+
+
+ private static void nodes(SB sb, Collection<Node> all) {
+ // Just the Nodes first, in a cluster no edges
+ sb.i().p("subgraph cluster_Nodes {\n").ii(); // Magic "cluster_" in the subgraph name
+ for( Node n : all ) {
+ if( n instanceof ProjNode || n instanceof CProjNode || n instanceof MemMergeNode )
+ continue; // Do not emit, rolled into MultiNode or Scope cluster already
+ sb.i().p(n.uniqueName()).p(" [ ");
+ if( n instanceof MultiNode && !(n instanceof StartNode) ) {
+ // Make a box with the MultiNode on top, and all the projections on the bottom
+ sb. p("shape=plaintext label=<\n").ii();
+ sb.i().p("<TABLE BORDER=\"0\" CELLBORDER=\"1\" CELLSPACING=\"0\" CELLPADDING=\"4\">\n");
+ // Row over single cell for node label
+ cell(sb.i().p("<TR>"), n.glabel(), n, null).p("</TR>\n");
+ // Row over single cell, for nested table
+ sb.i().p("<TR><TD>\n").ii();
+ sb.i().p("<TABLE BORDER=\"0\" CELLBORDER=\"1\" CELLSPACING=\"0\">").p("\n");
+ sb.i().p("<TR>");
+ n._outputs.sort((x,y) -> x instanceof ProjNode xp && y instanceof ProjNode yp ? (xp._idx - yp._idx) : ((x==null ? 99999 : x._nid) - (y==null ? 99999 : y._nid)));
+ boolean empty_row=true;
+ for( Node use : n._outputs ) {
+ int idx = idx(n);
+ if( idx != -1 ) {
+ cell(sb,use.glabel(),use,"p"+idx);
+ empty_row=false;
+ }
+ }
+ // At least one cell on row
+ if( empty_row ) sb.p("<TD></TD>");
+ sb. p("</TR>").p("\n");
+ sb.i().p("</TABLE>").p("\n").di();
+ sb.i().p("</TD></TR>\n");
+ sb.i().p("</TABLE>>\n").di();
+ sb.i().p("];\n");
+
+ } else {
+ // control nodes have box shape
+ // other nodes are ellipses, i.e. default shape
+ //else if (n instanceof PhiNode) sb.p("style=filled fillcolor=lightyellow ");
+ node(sb,n.glabel(),n);
+ sb.p("];\n");
+ }
+ }
+ // Force Region & Phis to line up
+ for (Node n : all) {
+ if (n instanceof RegionNode region) {
+ sb.i().p("{ rank=same; ");
+ sb.p(region.uniqueName()).p(";");
+ for (Node phi : region._outputs)
+ if (phi instanceof PhiNode) sb.p(phi.uniqueName()).p(";");
+ sb.p("}\n");
+ }
+ }
+ sb.di().i().p("}").nl(); // End Node cluster
+ }
+
+ // Build a nested scope display, walking the _prev edge
+ private static void scope( SB sb, ScopeNode scope ) {
+ sb.i().p("node [shape=plaintext];\n");
+ int last = scope.nIns();
+ int max = scope._lexSize.size()+1; // One more than lexsize
+ for( int i = 0; i < max; i++ ) {
+ int level = max-i-1;
+ String scopeName = makeScopeName(scope, level);
+ sb.i().p("subgraph cluster_").p(scopeName).p(" {\n").ii(); // Magic "cluster_" in the subgraph name
+ sb.i().p(scopeName).p(" [label=<\n").ii();
+ sb.i().p("<TABLE BORDER=\"0\" CELLBORDER=\"1\" CELLSPACING=\"0\">\n");
+ int lexStart = level==0 ? 0 : scope._lexSize.at(level-1);
+
+ // Special for memory ScopeMinNode
+ MemMergeNode n = scope.nIns()>1 ? scope.mem() : null;
+ if( level==0 && n!=null && n.nIns()>2 ) {
+ sb.i().p("<TR>");
+ for( int m=2; m<n.nIns(); m++ )
+ cell(sb,"#"+m,n.alias(m),"m"+m);
+ sb.p("</TR>\n"); // End scope level
+ }
+
+ // Scope variables, empty if none
+ if( lexStart<last ) {
+ sb.i().p("<TR>\n");
+ for( int j=lexStart; j<last; j++ ) {
+ if( scope.in(j)==null ) continue;
+ var v = scope._vars.at(j);
+ cell(sb.i(),v._name,scope.in(j),makePortName(scopeName, v._name)).nl();
+ }
+ last = lexStart;
+ sb.i().p("</TR>\n");
+ }
+ sb.i().p("</TABLE>>];\n").di();
+ // Scope label
+ sb.i().p(scopeName).p("A [label=\"").p(level).p("\" shape=doublecircle style=filled fillcolor=aqua fontsize=10 margin=0 width=0.2 ];\n");
+ }
+ // Scope clusters nest, so the graphics shows the nested scopes, so
+ // they are not closed as they are printed; so they just keep nesting.
+ // We close them all at once here.
+ for( int i=0; i<max; i++ )
+ sb.di().i().p("}\n");
+ }
+
+ // Append a cell, with color
+ private static SB cell(SB sb, String text, Node n, String port) {
+ sb.p("<TD");
+ String color = color(n);
+ sb.p(" BGCOLOR=\"").p(color).p("\"");
+ if( port!=null ) sb.p(" PORT=\"").p(port).p("\"");
+ return colorcell(sb.p(">"),text,n,dark(color)).p("</TD>");
+ }
+ private static SB node(SB sb, String text, Node n) {
+ String color = color(n);
+ sb.p("style=filled fillcolor=").p(color).p(" ");
+ String shape = switch( n ) {
+ case FunNode fun -> "shape=box peripheries=2";
+ case CFGNode cfg -> "shape=box";
+ default -> "";
+ };
+ sb.p(shape).p(" ");
+ return colorcell(sb.p("label=<"),text,n,dark(color)).p(">");
+ }
+
+ private static String color(Node n) {
+ return switch( n ) {
+ case CFGNode cfg -> "yellow";
+ case NewNode nnn -> "lightgreen";
+ case StructNode s -> "lightgreen";
+ default -> typeColor(n._type);
+ };
+ }
+ private static String typeColor(Type t) {
+ return t==null ? "white" : switch( t ) {
+ case TypeMem mem -> "blue";
+ case TypeMemPtr tmp -> "green";
+ case TypeFunPtr tfp -> "orange";
+ case TypeRPC rpc -> "antiquewhite";
+ case TypeInteger ti -> "lightblue";
+ case TypeFloat tf -> "aqua";
+ case Type tn -> tn==Type.NIL ? "lightgray" : "red";
+ };
+ }
+ private static final String[] DARKS = new String[]{"blue","green","black"};
+ private static boolean dark(String color) { return Utils.find(DARKS,color) != -1; }
+
+
+
+ // Called with an open div
+ private static SB colorcell(SB sb, String text, Node n, boolean dark) {
+ if( dark ) sb.p("<font color=\"white\">");
+ sb.p(text);
+ if( n._type!=null ) {
+ sb.p("<br /><font point-size=\"10\">");
+ n._type.gprint(sb);
+ sb.p("</font>");
+ }
+ if( dark ) sb.p("</font>");
+ return sb;
+ }
+
+
+ private static String makeScopeName(ScopeNode sn, int level) { return sn.uniqueName() + "_" + level; }
+ private static String makePortName(String scopeName, String varName) { return scopeName + "_" + varName; }
+
+ // Walk the node edges
+ private static void nodeEdges(SB sb, ScopeNode scope, Collection<Node> all) {
+ // All them edge labels
+ String scopeName = scope!=null ? makeScopeName(scope, 0) : null;
+ sb.i().p("edge [ fontname=Helvetica, fontsize=8 ];\n");
+ for( Node n : all ) {
+ // Do not display the Constant->Start edge;
+ if( n instanceof ConstantNode ||
+ n instanceof XCtrlNode ||
+ // ProjNodes handled by Multi;
+ n instanceof ProjNode ||
+ n instanceof CProjNode ||
+ // ScopeNodes are done separately
+ n instanceof ScopeNode ||
+ n instanceof MemMergeNode
+ )
+ continue;
+ if( n.isDead() )
+ throw Utils.TODO();
+ // Normal edges
+ for( int i=0; i<n.nIns(); i++ ) {
+ Node def = n.in(i);
+ if( def==null ) continue;
+ sb.i().p(n.uniqueName()).p(" -> ");
+ if( n instanceof PhiNode && def instanceof RegionNode ) {
+ // Draw a dotted use->def edge from Phi to Region.
+ sb.p(def.uniqueName());
+ sb.p(" [style=dotted taillabel=").p(i).p("];\n");
+ } else {
+ // Most edges land here use->def
+ if( def instanceof CProjNode proj ) {
+ String mname = proj.ctrl().uniqueName();
+ sb.p(mname).p(":p").p(proj._idx);
+ } else if( def instanceof ProjNode proj ) {
+ String mname = proj.in(0).uniqueName();
+ sb.p(mname).p(":p").p(proj._idx);
+ } else sb.p(def.uniqueName());
+ // Number edges, so we can see how they track
+ sb.p("[taillabel=").p(i);
+ // Color the edge
+ nodeEdgeColor(sb,def._type);
+ // Backedges do not add a ranking constraint
+ if( i==2 && (n instanceof PhiNode || n instanceof LoopNode) )
+ sb.p(" constraint=false");
+ sb.p("];\n");
+ }
+ }
+
+ // Bonus edge if hooked by parser
+ if( (n.iskeep() || n.isUnused()) && scopeName != null ) {
+ sb.i().p(scopeName).p(" -> ").p(n.uniqueName()).p(" [ style=dashed color=grey];\n");
+ }
+ // Force functions above return
+ if( n instanceof ReturnNode ret && ret.inProgress() && !ret.fun().isDead() )
+ sb.i().p(ret.ctrl().uniqueName()).p(" -> ").p(ret.fun().uniqueName()).p("[style=invis]\n");
+ }
+ }
+
+ private static void nodeEdgeColor(SB sb, Type t) {
+ sb.p(" color=").p(typeColor(t));
+ }
+
+ // Walk the scope edges
+ private static void scopeEdges( SB sb, ScopeNode scope ) {
+ sb.i().p("edge [style=dashed color=cornflowerblue];\n");
+ int level=0;
+ for( var v : scope._vars ) {
+ if( v._idx==1 ) continue; // Memory done separately
+ Node def = scope.in(v._idx);
+ while( def instanceof ScopeNode lazy )
+ def = lazy.in(v._idx);
+ if( def==null ) continue;
+ while( level < scope._lexSize.size() && v._idx >= scope._lexSize.at(level) )
+ level++;
+ String scopeName = makeScopeName(scope, level);
+ sb.i()
+ .p(scopeName).p(":")
+ .p('"').p(makePortName(scopeName, v._name)).p('"') // wrap port name with quotes because $ctrl is not valid unquoted
+ .p(" -> ");
+ defPort(sb,def).p(";\n");
+ }
+
+ // Memory
+ if( scope.nIns()>1 ) {
+ MemMergeNode n = scope.mem();
+ for( int i=2; i<n.nIns(); i++ ) {
+ Node def = n.in(i);
+ while( def instanceof ScopeNode lazy )
+ def = lazy.in(i);
+ if( def==null ) continue;
+ String scopeName = makeScopeName(scope, 0);
+ sb.i().p(scopeName).p(":m").p(i).p(" -> ");
+ defPort(sb,def).p(";\n");
+ }
+ }
+
+ }
+
+ // (C)Projection index or -1
+ private static int idx(Node n) {
+ return n instanceof ProjNode p ? p._idx : (n instanceof CProjNode cp ? cp._idx : -1);
+ }
+
+ private static SB defPort(SB sb, Node def) {
+ int idx = idx(def);
+ return idx != -1
+ ? sb.p(def.in(0).uniqueName()).p(":p").p(idx)
+ : sb.p(def.uniqueName());
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/ListScheduler.java b/chapter20/src/main/java/com/seaofnodes/simple/ListScheduler.java
new file mode 100644
index 00000000..18055e19
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/ListScheduler.java
@@ -0,0 +1,231 @@
+ package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.IterPeeps.WorkList;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.*;
+import java.util.*;
+
+public abstract class ListScheduler {
+
+ // eXtra per-node stuff for scheduling.
+ private static final IdentityHashMap<Node,XSched> XS = new IdentityHashMap<>();
+ private static class XSched {
+ static final Ary<XSched> FREE = new Ary<>(XSched.class);
+ static void alloc(CFGNode bb, Node n) {
+ XSched x = FREE.pop();
+ XS.put(n, (x==null ? new XSched() : x).init(bb,n));
+ }
+ void free() { _n = null; FREE.push(this); }
+
+ static XSched get(Node n) { return n==null ? null : XS.get(n); }
+
+ private XSched init(CFGNode bb, Node n) {
+ _n = n;
+ _bcnt = 0;
+ _ruse = _rdef = _single = false;
+
+ // Count block-locals and remote inputs
+ if( !(n instanceof PhiNode) )
+ for( Node def : n._inputs )
+ if( def != null && def != bb ) {
+ if( def.cfg0()==bb ) _bcnt++; // Raise block-local input count
+ else _ruse = true;
+ }
+ // Count remote outputs and allowed registers
+ if( n instanceof MultiNode )
+ for( Node use : n._inputs )
+ computeSingleRDef(bb,use);
+ else
+ computeSingleRDef(bb,n);
+ return this;
+ }
+
+ private void computeSingleRDef(CFGNode bb, Node n) {
+ RegMaskRW rmask = n instanceof MachNode mach ? mach.outregmap().copy() : null;
+ for( Node use : n._outputs ) {
+ // Remote use, so this is a remote def
+ if( use!=null && use.cfg0()!=bb ) _rdef = true;
+ // And mask between n's def mask and all n's users masks'
+ if( use instanceof MachNode mach && rmask != null )
+ for( int i=1; i<use.nIns(); i++ )
+ if( use.in(i)==n )
+ rmask.and(mach.regmap(i));
+ }
+ // Defines in a single register
+ _single = rmask!=null && rmask.size1();
+ }
+
+ // If _bcnt==0, declare ready; move user bcnts into rcnts.
+ boolean isReady() {
+ if( _bcnt > 0 || _rcnt > 0 ) return false;
+ if( _n instanceof MultiNode )
+ for( Node use : _n._outputs )
+ if( use instanceof ProjNode ) readyUp(use);
+ // anti-dep from a multireg directly
+ else _readyUp(use);
+ else
+ readyUp(_n);
+ return true;
+ }
+ private static void readyUp(Node n) {
+ for( Node use : n._outputs )
+ _readyUp(use);
+ }
+ private static void _readyUp(Node use) {
+ XSched xs = get(use);
+ if( xs!=null && !(use instanceof PhiNode) )
+ { assert xs._bcnt>0; xs._bcnt--; xs._rcnt++; }
+ }
+
+ boolean decIsReady() {
+ assert _rcnt > 0;
+ _rcnt--;
+ return isReady();
+ }
+
+ Node _n; // Node this extra is for
+ int _bcnt; // Not-ready not-scheduled inputs
+ int _rcnt; // Ready not-scheduled inputs
+ boolean _ruse; // Node IS a "remote use", uses a other-block value
+ boolean _rdef; // Node IS a "remote def" of a value used in other block
+ boolean _single; // Defines a single register, likely to conflict
+ }
+
+
+ // List schedule every block
+ public static void sched( CodeGen code ) {
+ XS.clear();
+ for( CFGNode bb : code._cfg )
+ if( bb.blockHead() )
+ local(bb);
+ }
+
+ // Classic list scheduler
+ private static void local( CFGNode bb ) {
+ assert XS.isEmpty();
+ int len = bb.nOuts();
+
+ // Count block-locals, remote inputs and outputs
+ for( int i=0; i<len; i++ )
+ XSched.alloc(bb,bb.out(i));
+
+ // Nodes are ready if they are not used by other nodes in this block.
+ // Move ready up front.
+ int ready = 0;
+ for( int i=0; i<len; i++ )
+ if( XSched.get(bb.out(i)).isReady() ) // No block-local inputs?
+ bb._outputs.swap(ready++,i); // Move into ready set
+ assert len==0 || ready > 0;
+
+ // Classic list scheduler. Behind sched is scheduled. Between sched
+ // and ready have zero counts and are ready to schedule. Ahead of
+ // ready is undefined.
+ //
+ // As nodes are scheduled, the nodes they use decrement their bcnts[]. Once
+ // that gets to 0, all the nodes using it are scheduled, so it's ready.
+ int sched = 0;
+ while( sched < len ) {
+ assert sched < ready;
+ int pick = best(bb._outputs,sched,ready); // Pick best
+ Node best = bb._outputs.swap(pick,sched++); // Swap best to head of ready and move into the scheduled set
+ // Lower ready count of users, and since projections are ready as
+ // soon as their multi is ready, lower those now too.
+ for( Node use : best._outputs )
+ if( use instanceof ProjNode )
+ for( Node useuse : use._outputs )
+ ready = ready(bb,useuse,ready);
+ else
+ ready = ready(bb,use,ready);
+ }
+
+ // Reset for next block
+ for( XSched x : XS.values() )
+ x.free();
+ XS.clear();
+ }
+
+ private static int ready(CFGNode bb, Node use, int ready) {
+ if( use!=null && !(use instanceof PhiNode) && use.in(0)==bb && XSched.get(use).decIsReady() )
+ bb._outputs.set(ready++, use); // Became ready, move into ready set
+ //bb._outputs.swap(ready++,use); // Became ready, move into ready set
+ return ready;
+ }
+
+
+ // Pick best between sched and ready.
+ private static int best( Ary<Node> blk, int sched, int ready ) {
+ int pick = sched;
+ int score = score(blk.at(pick));
+ for( int i=sched+1; i<ready; i++ ) {
+ int nscore = score(blk.at(i));
+ if( nscore > score )
+ { score = nscore; pick = i; }
+ }
+ return pick;
+ }
+
+ // Highest score wins. Max at 1000, min at 10, except specials.
+ private static final int[] CNT = new int[3];
+ static int score( Node n ) {
+ if( n instanceof ProjNode ) return 1001; // Pinned at block entry
+ if( n instanceof CProjNode ) return 1001; // Pinned at block entry
+ if( n instanceof PhiNode ) return 1000;
+ if( n instanceof CFGNode ) return 1; // Pinned at block exit
+
+ int score = 500;
+ // Ideal nodes ignore register pressure scheduling
+ if( !(n instanceof MachNode) )
+ return score;
+
+ // Register pressure local scheduling: avoid overlapping specialized
+ // registers usages.
+
+ // Subtract 10 if this op forces a live range to exist that cannot be
+ // resolved immediately; i.e., live count goes up. Scale to 20 if
+ // multi-def.
+
+ // Subtract 100 if this op forces a single-def live range to exist
+ // which might conflict on the same register with other live ranges.
+ // Defines a single register based on def & uses, and the output is not
+ // ready. Scale to 200 for multi-def.
+ CNT[1]=CNT[2]=0;
+ XSched xn = XSched.get(n);
+ if( xn._rdef ) score = 200; // If defining a remote value, just generically stall alot
+ if( n instanceof MultiNode ) {
+ for( Node use : n._outputs )
+ singleUseNotReady( use, xn._single );
+ } else if( n.nOuts() == 1 )
+ singleUseNotReady( n, xn._single );
+ score += -10 * Math.min( CNT[1], 2 );
+ score += -100 * Math.min( CNT[2], 2 );
+
+ // Add 10 if this op ends a single-def live range, add 20 for 2 or more.
+ // Scale to 100,200 if the single-def is also single-register.
+ CNT[1]=CNT[2]=0;
+ for( int i=1; i<n.nIns(); i++ ) {
+ XSched xd = XSched.get( n.in(i) );
+ if( xd != null && xd._n.nOuts()==1 )
+ CNT[xd._single || ((MachNode)n).regmap(i).size1() ? 2 : 1]++;
+ }
+ score += 10 * Math.min( CNT[1], 2 );
+ score += 100 * Math.min( CNT[2], 2 );
+
+ //// Nothing special
+ //if( n instanceof Pe ) return 500; // RISC want to go after PE
+ //if( n instanceof Risc ) return 400; // RISC want to go after PE
+ assert 10 <= score && score <= 990;
+ return score;
+ }
+
+ // Single use, and that use is not ready to fire once this one does.
+ // If true, stalling 'n' might reduce 'n's lifetime.
+ // Return 0 for false, 1 if true, 10 if also single register
+ private static void singleUseNotReady( Node n, boolean single ) {
+ if( n.nOuts() != 1 ) return;
+ XSched xu = XSched.get(n.out(0));
+ if( xu !=null && xu._bcnt==0 )
+ return;
+ CNT[single ? 2 : 1]++;
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/Machine.java b/chapter20/src/main/java/com/seaofnodes/simple/Machine.java
new file mode 100644
index 00000000..b29e9aba
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/Machine.java
@@ -0,0 +1,21 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.node.CFGNode;
+import com.seaofnodes.simple.node.IfNode;
+import com.seaofnodes.simple.node.Node;
+
+abstract public class Machine {
+ // Human readable machine name. Something like "x86-64" or "arm" or "risc5"
+ public abstract String name();
+ // Human-readable name for a register number, e.g. "RAX" or "R0"
+ public abstract String reg( int reg );
+ // Create a split op; any register to any register, including stack slots
+ public abstract Node split();
+ // Return a MachNode unconditional branch
+ public abstract CFGNode jump();
+ // Break an infinite loop
+ public abstract IfNode never( CFGNode ctrl );
+ // Instruction select from ideal nodes
+ public abstract Node instSelect( Node n );
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/Parser.java b/chapter20/src/main/java/com/seaofnodes/simple/Parser.java
new file mode 100644
index 00000000..61a53d68
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/Parser.java
@@ -0,0 +1,1729 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.*;
+import java.text.ParseException;
+import java.util.*;
+
+/**
+ * The Parser converts a Simple source program to the Sea of Nodes intermediate
+ * representation directly in one pass. There is no intermediate Abstract
+ * Syntax Tree structure.
+ * <p>
+ * This is a simple recursive descent parser. All lexical analysis is done here as well.
+ */
+public class Parser {
+
+ public static ConstantNode ZERO; // Very common node, cached here
+ public static ConstantNode NIL; // Very common node, cached here
+ public static XCtrlNode XCTRL; // Very common node, cached here
+
+ // Compile driver
+ public final CodeGen _code;
+
+ // The Lexer. Thin wrapper over a byte[] buffer with a cursor.
+ private final Lexer _lexer;
+
+ /**
+ * Current ScopeNode - ScopeNodes change as we parse code, but at any point of time
+ * there is one current ScopeNode. The reason the current ScopeNode can change is to do with how
+ * we handle branching. See {@link #parseIf()}.
+ * <p>
+ * Each ScopeNode contains a stack of lexical scopes, each scope is a symbol table that binds
+ * variable names to Nodes. The top of this stack represents current scope.
+ * <p>
+ * We keep a list of all ScopeNodes so that we can show them in graphs.
+ * @see #parseIf()
+ * @see #_xScopes
+ */
+ public ScopeNode _scope;
+
+ /**
+ * List of keywords disallowed as identifiers
+ */
+ public static final HashSet<String> KEYWORDS = new HashSet<>(){{
+ add("bool");
+ add("break");
+ add("byte");
+ add("continue");
+ add("else");
+ add("f32");
+ add("f64");
+ add("false");
+ add("flt");
+ add("i16");
+ add("i32");
+ add("i64");
+ add("i8");
+ add("if");
+ add("int");
+ add("new");
+ add("null");
+ add("return");
+ add("struct");
+ add("true");
+ add("u1");
+ add("u16");
+ add("u32");
+ add("u8");
+ add("while");
+ }};
+
+ /**
+ * We clone ScopeNodes when control flows branch; it is useful to have
+ * a list of all active ScopeNodes for purposes of visualization of the SoN graph
+ */
+ public final Stack<ScopeNode> _xScopes = new Stack<>();
+
+ ScopeNode _continueScope;
+ ScopeNode _breakScope; // Merge all the while-breaks here
+ FunNode _fun; // Current function being parsed
+
+ // Mapping from a type name to a Type. The string name matches
+ // `type.str()` call. No TypeMemPtrs are in here, because Simple does not
+ // have C-style '*ptr' references.
+ public static HashMap<String, Type> TYPES;
+
+ // Mapping from a type name to the constructor for a Type.
+ public final HashMap<String, StructNode> INITS;
+
+
+ public Parser(CodeGen code, TypeInteger arg) {
+ _code = code;
+ _lexer = new Lexer(code._src);
+ _scope = new ScopeNode();
+ _continueScope = _breakScope = null;
+ ZERO = con(TypeInteger.ZERO).keep();
+ NIL = con(Type.NIL).keep();
+ XCTRL= new XCtrlNode().peephole().keep();
+ TYPES = defaultTypes();
+ INITS = new HashMap<>();
+ }
+
+ @Override
+ public String toString() { return _lexer.toString(); }
+
+ public static HashMap<String, Type> defaultTypes() {
+ return new HashMap<>() {{
+ put("bool",TypeInteger.U1 );
+ put("byte",TypeInteger.U8 );
+ put("f32" ,TypeFloat .F32);
+ put("f64" ,TypeFloat .F64);
+ put("flt" ,TypeFloat .F64);
+ put("i16" ,TypeInteger.I16);
+ put("i32" ,TypeInteger.I32);
+ put("i64" ,TypeInteger.BOT);
+ put("i8" ,TypeInteger.I8 );
+ put("int" ,TypeInteger.BOT);
+ put("u1" ,TypeInteger.U1 );
+ put("u16" ,TypeInteger.U16);
+ put("u32" ,TypeInteger.U32);
+ put("u8" ,TypeInteger.U8 );
+ put("val" ,Type.TOP); // Marker type, indicates type inference
+ put("var" ,Type.BOTTOM); // Marker type, indicates type inference
+ }};
+ }
+
+ // Debugging utility to find a Node by index
+ public Node f(int nid) { return _code.f(nid); }
+
+ private Node ctrl() { return _scope.ctrl(); }
+ private <N extends Node> N ctrl(N n) { return _scope.ctrl(n); }
+
+ public void parse() { parse(false); }
+ public void parse(boolean show) {
+ _xScopes.push(_scope);
+ _scope.define(ScopeNode.CTRL, Type.CONTROL , false, null, _lexer);
+ _scope.define(ScopeNode.MEM0, TypeMem.BOT , false, null, _lexer);
+ _scope.define(ScopeNode.ARG0, TypeInteger.BOT, false, null, _lexer);
+
+ ctrl(XCTRL);
+ _scope.mem(new MemMergeNode(false));
+
+ // Parse whole program, as-if function header "{ int arg -> body }"
+ parseFunctionBody(_code._main,loc(),"arg");
+ _code.link(_code._main)._name = "main";
+
+ if( !_lexer.isEOF() ) throw _errorSyntax("unexpected");
+
+ // Clean up and reset
+ _xScopes.pop();
+ _scope.kill();
+ for( StructNode init : INITS.values() )
+ init.unkeep().kill();
+ INITS.clear();
+ _code._stop.peephole();
+ if( show ) showGraph();
+ }
+
+ /**
+ * Parses a function body, assuming the header is parsed.
+ */
+ private ReturnNode parseFunctionBody(TypeFunPtr sig, Lexer loc, String... ids) {
+ // Stack parser state on the local Java stack, and unstack it later
+ Node oldctrl = ctrl().keep();
+ Node oldmem = _scope.mem().keep();
+ FunNode oldfun = _fun;
+ ScopeNode breakScope = _breakScope; _breakScope = null;
+ ScopeNode continueScope = _continueScope; _continueScope = null;
+
+ FunNode fun = _fun = (FunNode)peep(new FunNode(loc(),sig,null,_code._start));
+ // Once the function header is available, install in linker table -
+ // allowing recursive functions. Linker matches on declared args and
+ // exact fidx, and ignores the return (because the fidx will only match
+ // the exact single function).
+ _code.link(fun);
+
+ Node rpc = new ParmNode("$rpc",0,TypeRPC.BOT,fun,con(TypeRPC.BOT)).peephole();
+
+ // Build a multi-exit return point for all function returns
+ RegionNode r = new RegionNode((Lexer)null,null,null).init();
+ assert r.inProgress();
+ PhiNode rmem = new PhiNode(ScopeNode.MEM0,TypeMem.BOT,r,null).init();
+ PhiNode rrez = new PhiNode(ScopeNode.ARG0,Type.BOTTOM,r,null).init();
+ ReturnNode ret = new ReturnNode(r, rmem, rrez, rpc, fun).init();
+ fun.setRet(ret);
+ assert ret.inProgress();
+ _code._stop.addDef(ret);
+
+ // Pre-call the function from Start, with worse-case arguments. This
+ // represents all the future, yet-to-be-parsed functions calls and
+ // external calls.
+ _scope.push(ScopeNode.Kind.Function);
+ ctrl(fun); // Scope control from function
+ // Private mem alias tracking per function
+ MemMergeNode mem = new MemMergeNode(true);
+ mem.addDef(null); // Alias#0
+ mem.addDef(new ParmNode(ScopeNode.MEM0,1,TypeMem.BOT,fun,con(TypeMem.BOT)).peephole()); // All aliases
+ _scope.mem(mem);
+ // All args, "as-if" called externally
+ for( int i=0; i<ids.length; i++ ) {
+ Type t = sig.arg(i);
+ _scope.define(ids[i], t, false, new ParmNode(ids[i],i+2,t,fun,con(t)).peephole(), loc);
+ }
+
+ // Parse the body
+ Node last=ZERO;
+ while (!peek('}') && !_lexer.isEOF())
+ last = parseStatement();
+
+ // Last expression is the return
+ if( ctrl()._type==Type.CONTROL )
+ fun.addReturn(ctrl(), _scope.mem().merge(), last);
+
+ // Pop off the inProgress node on the multi-exit Region merge
+ assert r.inProgress();
+ r ._inputs.pop();
+ rmem._inputs.pop();
+ rrez._inputs.pop();
+ r._loc = loc(); // Final position
+ assert !r.inProgress();
+
+ // Force peeps, which have been avoided due to inProgress
+ ret.setDef(1,rmem.peephole());
+ ret.setDef(2,rrez.peephole());
+ ret.setDef(0,r.peephole());
+ ret = (ReturnNode)ret.peephole();
+
+ // Function scope ends
+ _scope.pop();
+ _fun = oldfun;
+ _breakScope = breakScope;
+ _continueScope = continueScope;
+ // Reset control and memory to pre-function parsing days
+ ctrl(oldctrl.unkeep());
+ _scope.mem(oldmem.unkeep());
+
+ return ret;
+ }
+
+ /**
+ * Parses a block
+ *
+ * <pre>
+ * '{' statements '}'
+ * </pre>
+ * Does not parse the opening or closing '{}'
+ * @return a {@link Node} or {@code null}
+ */
+ private Node parseBlock(ScopeNode.Kind kind) {
+ // Enter a new scope
+ _scope.push(kind);
+ Node last = ZERO;
+ while (!peek('}') && !_lexer.isEOF())
+ last = parseStatement();
+ // Exit scope
+ last.keep();
+ _scope.pop();
+ return last.unkeep();
+ }
+
+ /**
+ * Parses a statement
+ *
+ * <pre>
+ * returnStatement | declStatement | blockStatement | ifStatement | expressionStatement
+ * </pre>
+ * @return a {@link Node} or {@code null}
+ */
+ private Node parseStatement() {
+ if( false ) return null;
+ else if (matchx("return") ) return parseReturn();
+ else if (matchx("if") ) return parseIf();
+ else if (matchx("while") ) return parseWhile();
+ else if (matchx("for") ) return parseFor();
+ else if (matchx("break") ) return parseBreak();
+ else if (matchx("continue")) return parseContinue();
+ else if (matchx("struct") ) return parseStruct();
+ else if (matchx("#showGraph")) return require(showGraph(),";");
+ else if (matchx(";") ) return null; // Empty statement
+ // Break ambiguity around leading function types and starting a block
+ else if (peek('{') && !isTypeFun() ) {
+ match("{");
+ return require(parseBlock(ScopeNode.Kind.Block),"}");
+ }
+ // Declaration or normal assignment/expression
+ else return parseDeclarationStatement();
+ }
+
+ /**
+ * Parses a while statement
+ *
+ * <pre>
+ * while ( expression ) statement
+ * </pre>
+ * @return a {@link Node}, never {@code null}
+ */
+ private Node parseWhile() {
+ require("(");
+ return parseLooping(false);
+ }
+
+
+ /**
+ * Parses a for statement
+ *
+ * <pre>
+ * for( var x=init; test; incr ) body
+ * </pre>
+ * @return a {@link Node}, never {@code null}
+ */
+ private Node parseFor() {
+ // { var x=init,y=init,...;
+ // while( test ) {
+ // body;
+ // next;
+ // }
+ // }
+ require("(");
+ _scope.push(ScopeNode.Kind.Block); // Scope for the index variables
+ if( !match(";") ) // Can be empty init "for(;test;next) body"
+ parseDeclarationStatement(); // Non-empty init
+ Node rez = parseLooping(true);
+ _scope.pop(); // Exit index variable scope
+ return rez;
+ }
+
+ // Shared by `for` and `while`
+ private Node parseLooping( boolean doFor ) {
+
+ var savedContinueScope = _continueScope;
+ var savedBreakScope = _breakScope;
+
+ // Loop region has two control inputs, the first is the entry
+ // point, and second is back edge that is set after loop is parsed
+ // (see end_loop() call below). Note that the absence of back edge is
+ // used as an indicator to switch off peepholes of the region and
+ // associated phis; see {@code inProgress()}.
+
+ ctrl(new LoopNode(loc(),ctrl()).peephole()); // Note we set back edge to null here
+
+ // At loop head, we clone the current Scope (this includes all
+ // names in every nesting level within the Scope).
+ // We create phis eagerly for all the names we find, see dup().
+
+ // Save the current scope as the loop head
+ ScopeNode head = _scope.keep();
+ // Clone the head Scope to create a new Scope for the body.
+ // Create phis eagerly as part of cloning
+ _xScopes.push(_scope = _scope.dup(true)); // The true argument triggers creating phis
+
+ // Parse predicate
+ var pred = peek(';') ? con(1) : parseAsgn();
+ require( doFor ? ";" : ")" );
+
+ // IfNode takes current control and predicate
+ Node ifNode = new IfNode(ctrl(), pred.keep()).peephole();
+ // Setup projection nodes
+ Node ifT = new CProjNode(ifNode. keep(), 0, "True" ).peephole().keep();
+ Node ifF = new CProjNode(ifNode.unkeep(), 1, "False").peephole();
+
+ // for( ;;next ) body
+ int nextPos = -1, nextEnd = -1;
+ if( doFor ) {
+ // Skip the next expression and parse it later
+ nextPos = pos();
+ skipAsgn();
+ nextEnd = pos();
+ require(")");
+ }
+
+ // Clone the body Scope to create the break/exit Scope which accounts for any
+ // side effects in the predicate. The break/exit Scope will be the final
+ // scope after the loop, and its control input is the False branch of
+ // the loop predicate. Note that body Scope is still our current scope.
+ ctrl(ifF);
+ _xScopes.push(_breakScope = _scope.dup());
+ _breakScope.addGuards(ifF,pred,true); // Up-cast predicate
+
+ // No continues yet
+ _continueScope = null;
+
+ // Parse the true side, which corresponds to loop body
+ // Our current scope is the body Scope
+ ctrl(ifT.unkeep()); // set ctrl token to ifTrue projection
+ _scope.addGuards(ifT,pred.unkeep(),false); // Up-cast predicate
+ parseStatement(); // Parse loop body
+ _scope.removeGuards(ifT);
+
+ // Merge the loop bottom into other continue statements
+ if (_continueScope != null) {
+ _continueScope = jumpTo(_continueScope);
+ _scope.kill();
+ _scope = _continueScope;
+ }
+
+ // Now append the next code onto the body code
+ if( doFor ) {
+ int old = pos(nextPos);
+ if( !peek(')') )
+ parseAsgn();
+ if( pos() != nextEnd )
+ throw errorSyntax( "Unexpected code after expression" );
+ pos(old);
+ }
+
+ // The true branch loops back, so whatever is current _scope.ctrl gets
+ // added to head loop as input. endLoop() updates the head scope, and
+ // goes through all the phis that were created earlier. For each phi,
+ // it sets the second input to the corresponding input from the back
+ // edge. If the phi is redundant, it is replaced by its sole input.
+ var exit = _breakScope;
+ head.endLoop(_scope, exit);
+ head.unkeep().kill();
+
+ _xScopes.pop(); // Cleanup
+ _xScopes.pop(); // Cleanup
+
+ _continueScope = savedContinueScope;
+ _breakScope = savedBreakScope;
+
+ // At exit the false control is the current control, and
+ // the scope is the exit scope after the exit test.
+ _xScopes.pop();
+ _xScopes.push(exit);
+ _scope = exit;
+ return ZERO;
+ }
+
+ private ScopeNode jumpTo(ScopeNode toScope) {
+ ScopeNode cur = _scope.dup();
+ ctrl(XCTRL); // Kill current scope
+ // Prune nested lexical scopes that have depth > than the loop head
+ // We use _breakScope as a proxy for the loop head scope to obtain the depth
+ while( cur._lexSize.size() > _breakScope._lexSize.size() )
+ cur.pop();
+ // If this is a continue then first time the target is null
+ // So we just use the pruned current scope as the base for the
+ // "continue"
+ if( toScope == null )
+ return cur;
+ // toScope is either the break scope, or a scope that was created here
+ assert toScope._lexSize.size() <= _breakScope._lexSize.size();
+ toScope.ctrl(toScope.mergeScopes(cur,loc()).peephole());
+ return toScope;
+ }
+
+ private void checkLoopActive() { if (_breakScope == null) throw error("No active loop for a break or continue"); }
+
+ private Node parseContinue() { checkLoopActive(); _continueScope = require(jumpTo( _continueScope ),";"); return ZERO; }
+ private Node parseBreak () {
+ checkLoopActive();
+ // At the time of the break, and loop-exit conditions are only valid if
+ // they are ALSO valid at the break. It is the intersection of
+ // conditions here, not the union.
+ _breakScope.removeGuards(_breakScope.ctrl());
+ _breakScope = require(jumpTo(_breakScope ),";");
+ _breakScope.addGuards(_breakScope.ctrl(), null, false);
+ return ZERO;
+ }
+
+ // Look for an unbalanced `)`, skipping balanced
+ private void skipAsgn() {
+ int paren=0;
+ while( true )
+ // Next X char handles skipping complex comments
+ switch( _lexer.nextXChar() ) {
+ case Character.MAX_VALUE:
+ throw Utils.TODO();
+ case ')':
+ if( --paren<0 ) {
+ posT( pos() - 1 );
+ return; // Leave the `)` behind
+ }
+ break;
+ case '(': paren ++; break;
+ default: break;
+ }
+ }
+
+
+ /**
+ * Parses a statement
+ *
+ * <pre>
+ * if ( expression ) statement [else statement]
+ * </pre>
+ * @return a {@link Node}, never {@code null}
+ */
+ private Node parseIf() {
+ // Parse predicate
+ require("(");
+ var pred = require(parseAsgn(), ")");
+ return parseTrinary(pred,true,"else");
+ }
+
+ // Parse a conditional expression, merging results.
+ private Node parseTrinary( Node pred, boolean stmt, String fside ) {
+ pred.keep();
+
+ // IfNode takes current control and predicate
+ Node ifNode = new IfNode(ctrl(), pred).peephole();
+ // Setup projection nodes
+ Node ifT = new CProjNode(ifNode. keep(), 0, "True" ).peephole().keep();
+ Node ifF = new CProjNode(ifNode.unkeep(), 1, "False").peephole().keep();
+ // In if true branch, the ifT proj node becomes the ctrl
+ // But first clone the scope and set it as current
+ ScopeNode fScope = _scope.dup(); // Duplicate current scope
+ _xScopes.push(fScope); // For graph visualization we need all scopes
+
+ // Parse the true side
+ ctrl(ifT.unkeep()); // set ctrl token to ifTrue projection
+ _scope.addGuards(ifT,pred,false); // Up-cast predicate
+ Node lhs = (stmt ? parseStatement() : parseAsgn()).keep(); // Parse true-side
+ _scope.removeGuards(ifT);
+
+ // See if a one-sided def was made: "if(pred) int x = 1;" and throw.
+ // See if any forward-refs were made, and copy them to the other side:
+ // "pred ? n*fact(n-1) : 1"
+ fScope.balanceIf(_scope);
+
+ ScopeNode tScope = _scope;
+
+ // Parse the false side
+ _scope = fScope; // Restore scope, then parse else block if any
+ ctrl(ifF.unkeep()); // Ctrl token is now set to ifFalse projection
+ // Up-cast predicate, even if not else clause, because predicate can
+ // remain true if the true clause exits: `if( !ptr ) return 0; return ptr.fld;`
+ _scope.addGuards(ifF,pred,true);
+ boolean doRHS = match(fside);
+ Node rhs = (doRHS
+ ? (stmt ? parseStatement() : parseAsgn())
+ : con(lhs._type.makeZero())).keep();
+ _scope.removeGuards(ifF);
+ if( doRHS )
+ fScope = _scope;
+ pred.unkeep();
+
+ // Check the trinary widening int/flt
+ if( !stmt ) {
+ rhs = widenInt( rhs.unkeep(), lhs._type ).keep();
+ lhs = widenInt( lhs.unkeep(), rhs._type ).keep();
+ }
+
+ _scope = tScope;
+ _xScopes.pop(); // Discard pushed from graph display
+ // See if a one-sided def was made: "if(pred) int x = 1;" and throw.
+ // See if any forward-refs were made, and copy them to the other side:
+ // "pred ? n*fact(n-1) : 1"
+ tScope.balanceIf(fScope);
+
+ // Merge results
+ RegionNode r = ctrl(tScope.mergeScopes(fScope,loc()));
+ Node ret = peep(new PhiNode("",lhs._type.meet(rhs._type),r,lhs.unkeep(),rhs.unkeep()));
+ // Immediately fail e.g. `arg ? 7 : ptr`
+ ParseException err;
+ if( !stmt && (err=ret.err()) !=null ) throw err;
+ r.peephole();
+ return ret;
+ }
+
+ /**
+ * Parses a return statement; "return" already parsed.
+ * The $ctrl edge is killed.
+ *
+ * <pre>
+ * 'return' expr ;
+ * </pre>
+ * @return an expression {@link Node}, never {@code null}
+ */
+ private Node parseReturn() {
+ var expr = require(parseAsgn(), ";");
+ // Need default memory, since it can be lazy, need to force
+ // a non-lazy Phi
+ _fun.addReturn(ctrl(), _scope.mem().merge(), expr);
+ ctrl(XCTRL); // Kill control
+ return expr;
+ }
+
+ /**
+ * Dumps out the node graph
+ * @return {@code null}
+ */
+ Node showGraph() {
+ System.out.println(new GraphVisualizer().generateDotOutput(_code._stop,_scope,_xScopes));
+ return null;
+ }
+
+ /** Parse: [name '='] expr
+ */
+ private Node parseAsgn() {
+ int old = pos();
+ String name = _lexer.matchId();
+ // Just a plain expression, no assignment.
+ // Distinguish `var==expr` from `var=expr`
+ if( name==null || KEYWORDS.contains(name) || !matchOpx('=','=') )
+ { pos(old); return parseExpression(); }
+
+ // Parse assignment expression
+ Node expr = parseAsgn();
+
+ // Final variable to update
+ Var def = _scope.lookup(name);
+ if( def==null )
+ throw error("Undefined name '" + name + "'");
+
+ // TOP fields are for late-initialized fields; these have never
+ // been written to, and this must be the final write. Other writes
+ // outside the constructor need to check the final bit.
+ if( _scope.in(def._idx)._type!=Type.TOP && def._final &&
+ // Inside a constructor, final assign is OK, outside nope
+ !(_scope.inCon() && def._idx >= _scope._lexSize.last()) )
+ throw error("Cannot reassign final '"+name+"'");
+
+ // Lift expression, based on type
+ Node lift = liftExpr(expr.keep(), def.type(), def._final);
+ // Update
+ _scope.update(name,lift);
+ // Return un-lifted expr
+ return expr.unkeep();
+ }
+
+ // Make finals deep; widen ints to floats; narrow wide int types.
+ // Early error if types do not match variable.
+ private Node liftExpr( Node expr, Type t, boolean xfinal ) {
+ assert !(expr._type instanceof TypeMemPtr tmp) || !tmp.isFRef();
+ // Final is deep on ptrs
+ if( xfinal && t instanceof TypeMemPtr tmp ) {
+ t = tmp.makeRO();
+ expr = peep(new ReadOnlyNode(expr));
+ }
+ // Auto-widen int to float
+ expr = widenInt( expr, t );
+ // Auto-narrow wide ints to narrow ints
+ expr = zsMask(expr,t);
+ // Type is sane
+ if( expr._type!=Type.BOTTOM && !expr._type.shallowISA(t) )
+ throw error("Type " + expr._type.str() + " is not of declared type " + t.str());
+ return expr;
+ }
+
+ private Node widenInt( Node expr, Type t ) {
+ return (expr._type instanceof TypeInteger || expr._type==Type.NIL) && t instanceof TypeFloat
+ ? peep(new ToFloatNode(expr)) : expr;
+ }
+
+ /**
+ * Parse declaration or expression statement
+ * declStmt = type var['=' exprAsgn][, var['=' exprAsgn]]* ';' | exprAsgn ';'
+ * <p>
+ * exprAsgn = var '=' exprAsgn | expr
+ */
+ private Node parseDeclarationStatement() {
+ Type t = type();
+ if( t == null )
+ return require(parseAsgn(),";");
+
+ // now parse var['=' asgnexpr] in a loop
+ Node n = parseDeclaration(t);
+ while( match(",") )
+ n = parseDeclaration(t);
+ return require(n,";");
+ }
+
+ /** Parse final: [!]var['=' asgn]
+ */
+ private Node parseDeclaration(Type t) {
+ assert t!=null;
+ // Has var/val instead of a user-declared type
+ boolean inferType = t==Type.TOP || t==Type.BOTTOM;
+ boolean hasBang = match("!");
+ Lexer loc = loc();
+ String name = requireId();
+ // Optional initializing expression follows
+ boolean xfinal = false;
+ Node expr;
+ if( match("=") ) {
+ expr = parseAsgn();
+ // TOP means val and val is always final
+ xfinal = (t==Type.TOP) ||
+ // BOTTOM is var and var is always not-final
+ (t!=Type.BOTTOM &&
+ // no Bang AND
+ !hasBang &&
+ // not-null (expecting null to be set to not-null)
+ expr._type != Type.NIL &&
+ // Pointers are final by default; int/flt are not-final by default.
+ (t instanceof TypeNil));
+ // var/val, then type comes from expression
+ if( inferType ) {
+ if( expr._type==Type.NIL )
+ throw error("a not-null/non-zero expression");
+ t = expr._type;
+ if( !xfinal ) t = t.glb(); // Widen if not final
+ }
+ if( t instanceof TypeFunPtr && expr._type instanceof TypeFunPtr tfp && tfp.isConstant() )
+ _code.link(tfp)._name = name;
+
+ } else {
+ // Need an expression to infer the type.
+ // Also, if not-null then need an initializing expression.
+ // Allowed in a class def, because type/init will happen in the constructor.
+ if( (inferType || (t instanceof TypeNil tn && !tn.nullable() )) && !_scope.inCon() )
+ throw errorSyntax("=expression");
+ // Initial value for uninitialized struct fields.
+ expr = switch( t ) {
+ // Nullable pointers get a NIL; not-null get a TOP which
+ // signals that they *must* be initialized in the constructor.
+ case TypeNil tn -> tn.nullable() ? NIL : con(Type.TOP);
+ case TypeInteger ti -> ZERO;
+ case TypeFloat tf -> con(TypeFloat.FZERO);
+ // Bottom signals type inference: they must be initialized in
+ // the constructor and that's when we'll discover the type.
+ case Type tt -> { assert tt==Type.BOTTOM; yield con(tt); }
+ };
+ }
+
+ // Lift expression, based on type
+ Node lift = liftExpr(expr, t, xfinal);
+
+ if( xfinal && t instanceof TypeMemPtr tmp )
+ t = tmp.makeRO();
+
+ // Lift type to the declaration. This will report as an error later if
+ // we cannot lift the type.
+ if( !lift._type.isa(t) )
+ lift = peep(new CastNode(t,null,lift));
+ // Define a new name
+ if( !_scope.define(name,t,xfinal,lift, loc) )
+ throw error("Redefining name '" + name + "'", loc);
+ return lift;
+ }
+
+
+
+ /**
+ * Parse a struct declaration, and return the following statement.
+ * Only allowed in top level scope.
+ * Structs cannot be redefined.
+ *
+ * @return The statement following the struct
+ */
+ private Node parseStruct() {
+ if (_xScopes.size() > 1) throw error("struct declarations can only appear in top level scope");
+ String typeName = requireId();
+ Type t = TYPES.get(typeName);
+ if( t!=null && !(t instanceof TypeMemPtr tmp && tmp.isFRef() ) )
+ throw error("struct '" + typeName + "' cannot be redefined");
+
+ // A Block scope parse, and inspect the scope afterward for fields.
+ _scope.push(ScopeNode.Kind.Constructor);
+ require("{");
+ while (!peek('}') && !_lexer.isEOF())
+ parseStatement();
+
+ // Grab the declarations and build fields and a Struct
+ int lexlen = _scope._lexSize.last();
+ int varlen = _scope._vars._len;
+ StructNode s = new StructNode();
+ Ary<Field> fs = new Ary<>(Field.class);
+ for( int i=lexlen; i<varlen; i++ ) {
+ s.addDef(_scope.in(i));
+ Var v = _scope._vars.at(i);
+ if( !v.isFRef() ) // Promote to outer scope, not defined here
+ fs.push(Field.make(v._name,v.type(),_code.getALIAS(),v._final));
+ }
+ TypeStruct ts = s._ts = TypeStruct.make(typeName, fs.asAry());
+ TYPES.put(typeName, TypeMemPtr.make(ts));
+ INITS.put(typeName,s.peephole().keep());
+ // Done with struct/block scope
+ require("}");
+ require(";");
+ _scope.pop();
+ return ZERO;
+ }
+
+
+ // Parse and return a type or null. Valid types always are followed by an
+ // 'id' which the caller must parse. This lets us distinguish forward ref
+ // types (which ARE valid here) from local vars in an (optional) forward
+ // ref type position.
+
+ // t = int|i8|i16|i32|i64|u8|u16|u32|u64|byte|bool | flt|f32|f64 | val | var | struct[?]
+ private Type type() {
+ int old1 = pos();
+ // Only type with a leading `{` is a function pointer...
+ if( peek('{') ) return typeFunPtr();
+
+ // Otherwise you get a type name
+ String tname = _lexer.matchId();
+ if( tname==null ) return null;
+
+ // Convert the type name to a type.
+ Type t0 = TYPES.get(tname);
+ // No new types as keywords
+ if( t0 == null && KEYWORDS.contains(tname) )
+ return posT(old1);
+ if( t0 == Type.BOTTOM || t0 == Type.TOP ) return t0; // var/val type inference
+ Type t1 = t0 == null ? TypeMemPtr.make(TypeStruct.makeFRef(tname)) :t0; // Null: assume a forward ref type
+ // Nest arrays and '?' as needed
+ Type t2 = t1;
+ while( true ) {
+ if( match("?") ) {
+ if( !(t2 instanceof TypeMemPtr tmp) )
+ throw error("Type "+t0+" cannot be null");
+ if( tmp.nullable() ) throw error("Type "+t2+" already allows null");
+ t2 = tmp.makeNullable();
+ } else if( match("[]") ) {
+ t2 = typeAry(t2);
+ } else
+ break;
+ }
+
+ // Check no forward ref
+ if( t0 != null ) return t2;
+ // Check valid forward ref, after parsing all the type extra bits.
+ // Cannot check earlier, because cannot find required 'id' until after "[]?" syntax
+ int old2 = pos();
+ match("!");
+ String id = _lexer.matchId();
+ if( !(peek(',') || peek(';') || match("->")) )
+ return posT(old1);
+ pos(old2); // Reset lexer to reparse
+ if( id==null )
+ return posT(old1); // Reset lexer to reparse
+ // Yes a forward ref, so declare it
+ TYPES.put(tname,t1);
+ return t2;
+ }
+
+ // Make an array type of t
+ private TypeMemPtr typeAry( Type t ) {
+ if( t instanceof TypeMemPtr tmp && tmp.notNull() )
+ throw error("Arrays of reference types must always be nullable");
+ String tname = "["+t.str()+"]";
+ Type ta = TYPES.get(tname);
+ if( ta != null ) return (TypeMemPtr)ta;
+ // Need make an array type.
+ TypeStruct ts = TypeStruct.makeAry(TypeInteger.U32,_code.getALIAS(),t,_code.getALIAS());
+ assert ts.str().equals(tname);
+ TypeMemPtr tary = TypeMemPtr.make(ts);
+ TYPES.put(tname,tary);
+ return tary;
+ }
+
+ // A function type is `{ type... -> type }` or `{ type }`.
+ private Type typeFunPtr() {
+ int old = pos(); // Record lexer position
+ match("{"); // Skip already-peeked '{'
+ Type t0 = type(); // Either return or first arg
+ if( t0==null ) return posT(old); // Not a function
+ if( match("}") ) // No-arg function { -> type }
+ return TypeFunPtr.make(match("?"),TypeTuple.BOT,t0);
+ Ary<Type> ts = new Ary<>(Type.class);
+ ts.push(t0); // First argument
+ while( true ) {
+ if( match("->") ) { // End of arguments, parse return
+ Type ret = type();
+ if( ret==null || !match("}") )
+ return posT(old); // Not a function
+ return TypeFunPtr.make(match("?"),TypeTuple.make(ts.asAry()),ret);
+ }
+ Type t1 = type();
+ if( t1==null ) return posT(old); // Not a function
+ ts.push(t1);
+ }
+ }
+
+ // True if a TypeFunPtr, without advancing parser
+ private boolean isTypeFun() {
+ int old = pos();
+ if( typeFunPtr()==null ) return false;
+ pos(old);
+ return true;
+ }
+
+ /**
+ * Parse an expression of the form:
+ *
+ * <pre>
+ * expr : bitwise [? expr [: expr]]
+ * </pre>
+ * @return an expression {@link Node}, never {@code null}
+ */
+ private Node parseExpression() {
+ Node expr = parseBitwise();
+ return match("?") ? parseTrinary(expr,false,":") : expr;
+ }
+
+ /**
+ * Parse an bitwise expression
+ *
+ * <pre>
+ * bitwise : compareExpr (('&' | '|' | '^') compareExpr)*
+ * </pre>
+ * @return a bitwise expression {@link Node}, never {@code null}
+ */
+ private Node parseBitwise() {
+ Node lhs = parseComparison();
+ while( true ) {
+ if( false ) ;
+ else if( match("&") ) lhs = new AndNode(loc(),lhs,null);
+ else if( match("|") ) lhs = new OrNode(loc(),lhs,null);
+ else if( match("^") ) lhs = new XorNode(loc(),lhs,null);
+ else break;
+ lhs.setDef(2,parseComparison());
+ lhs = peep(lhs);
+ }
+ return lhs;
+ }
+
+ /**
+ * Parse an expression of the form:
+ *
+ * <pre>
+ * expr : additiveExpr op additiveExpr
+ * </pre>
+ * @return an comparator expression {@link Node}, never {@code null}
+ */
+ private Node parseComparison() {
+ var lhs = parseShift();
+ while( true ) {
+ int idx=0; boolean negate=false;
+ // Test for any local nodes made, and "keep" lhs during peepholes
+ if( false ) ;
+ else if( match("==") ) { idx=2; lhs = new BoolNode.EQ(lhs, null); }
+ else if( match("!=") ) { idx=2; lhs = new BoolNode.EQ(lhs, null); negate=true; }
+ else if( match("<=") ) { idx=2; lhs = new BoolNode.LE(lhs, null); }
+ else if( match("<" ) ) { idx=2; lhs = new BoolNode.LT(lhs, null); }
+ else if( match(">=") ) { idx=1; lhs = new BoolNode.LE(null, lhs); }
+ else if( match(">" ) ) { idx=1; lhs = new BoolNode.LT(null, lhs); }
+ else break;
+ // Peepholes can fire, but lhs is already "hooked", kept alive
+ lhs.setDef(idx,parseShift());
+ lhs = peep(lhs.widen());
+ if( negate ) // Extra negate for !=
+ lhs = peep(new NotNode(lhs));
+ }
+ return lhs;
+ }
+
+ /**
+ * Parse an additive expression
+ *
+ * <pre>
+ * shiftExpr : additiveExpr (('<<' | '>>' | '>>>') additiveExpr)*
+ * </pre>
+ * @return a shift expression {@link Node}, never {@code null}
+ */
+ private Node parseShift() {
+ Node lhs = parseAddition();
+ while( true ) {
+ if( false ) ;
+ else if( match("<<") ) lhs = new ShlNode(loc(),lhs,null);
+ else if( match(">>>")) lhs = new ShrNode(loc(),lhs,null);
+ else if( match(">>") ) lhs = new SarNode(loc(),lhs,null);
+ else break;
+ lhs.setDef(2,parseAddition());
+ ParseException err;
+ if( (err=lhs.err()) != null )
+ throw err;
+ lhs = peep(lhs.widen());
+ }
+ return lhs;
+ }
+
+ /**
+ * Parse an additive expression
+ *
+ * <pre>
+ * additiveExpr : multiplicativeExpr (('+' | '-') multiplicativeExpr)*
+ * </pre>
+ * @return an add expression {@link Node}, never {@code null}
+ */
+ private Node parseAddition() {
+ Node lhs = parseMultiplication();
+ while( true ) {
+ if( false ) ;
+ else if( match("+") ) lhs = new AddNode(lhs,null);
+ else if( match("-") ) lhs = new SubNode(lhs,null);
+ else break;
+ lhs.setDef(2,parseMultiplication());
+ lhs = peep(lhs.widen());
+ }
+ return lhs;
+ }
+
+ /**
+ * Parse an multiplicativeExpr expression
+ *
+ * <pre>
+ * multiplicativeExpr : unaryExpr (('*' | '/') unaryExpr)*
+ * </pre>
+ * @return a multiply expression {@link Node}, never {@code null}
+ */
+ private Node parseMultiplication() {
+ var lhs = parseUnary();
+ while( true ) {
+ if( false ) ;
+ else if( match("*") ) lhs = new MulNode(lhs,null);
+ else if( match("/") ) lhs = new DivNode(lhs,null);
+ else break;
+ lhs.setDef(2,parseUnary());
+ lhs = peep(lhs.widen());
+ }
+ return lhs;
+ }
+
+ /**
+ * Parse a unary minus expression.
+ *
+ * <pre>
+ * unaryExpr : ('-') unaryExpr | '!') unaryExpr | postfixExpr | primaryExpr | '--' Id | '++' Id
+ * </pre>
+ * @return a unary expression {@link Node}, never {@code null}
+ */
+ private Node parseUnary() {
+ // Pre-dec/pre-inc
+ int old = pos();
+ if( match("--") || match("++") ) {
+ int delta = _lexer.peek(-1)=='+' ? 1 : -1; // Pre vs post
+ String name = _lexer.matchId();
+ if( name!=null ) {
+ Var n = _scope.lookup(name);
+ if( n != null && !(n.type() instanceof TypeMemPtr) ) {
+ if( n._final )
+ throw error("Cannot reassign final '"+n._name+"'");
+ Node expr = n.type() instanceof TypeFloat
+ ? peep(new AddFNode(_scope.in(n),con(TypeFloat.constant(delta))))
+ : zsMask(peep(new AddNode(_scope.in(n),con(delta))),n.type());
+ _scope.update(n,expr);
+ return expr;
+ }
+ }
+ // Reset, try again
+ pos(old);
+ }
+ if (match("-")) return peep(new MinusNode(parseUnary()).widen());
+ if (match("!")) return peep(new NotNode(parseUnary()));
+ return parsePostfix(parsePrimary());
+ }
+
+ /**
+ * Parse a primary expression:
+ *
+ * <pre>
+ * primaryExpr : integerLiteral | true | false | null | new Type | '(' expression ')' | Id['++','--']
+ * </pre>
+ * @return a primary {@link Node}, never {@code null}
+ */
+ private Node parsePrimary() {
+ if( _lexer.isNumber(_lexer.peek()) ) return parseLiteral();
+ if( matchx("true" ) ) return con(1);
+ if( matchx("false") ) return ZERO;
+ if( matchx("null" ) ) return NIL;
+ if( match ("(" ) ) return require(parseAsgn(), ")");
+ if( matchx("new" ) ) return alloc();
+ if( match ("{" ) ) return require(func(),"}");
+ // Expect an identifier now
+ Var n = requireLookupId();
+ Node rvalue = _scope.in(n);
+ if( rvalue._type == Type.BOTTOM )
+ if( rvalue instanceof FRefNode ) return rvalue;
+ else throw error("Cannot read uninitialized field '"+n._name+"'");
+ // Check for assign-update, x += e0;
+ char ch = _lexer.matchOperAssign();
+ if( ch==0 ) return rvalue;
+ Node op = opAssign(ch,rvalue,n._final,n.type(),n._name);
+ _scope.update(n,op);
+ return postfix(ch) ? rvalue.unkeep() : op;
+ }
+
+ // Check for assign-update, "x += e0".
+ // Returns "x + e0"; the caller assigns value.
+ // if ch is postfix, then lhs is kept and caller will unkeep and return it.
+ private Node opAssign(char ch, Node lhs, boolean xfinal, Type t, String name ) {
+ if( xfinal )
+ throw error("Cannot reassign final '"+name+"'");
+ // RHS of the update.
+ lhs.keep(); // Alive across parseAsgn
+ Node rhs =
+ (byte)ch == 1 ? con( 1) : // var++
+ (byte)ch == -1 ? con(-1) : // var--
+ parseAsgn(); // var op= rhs
+ if( !postfix(ch) ) lhs.unkeep(); // Allow to die in next peep
+ // 4 cases:
+ // int + int ==>> narrow int
+ // int + flt ==>> error, caller must fail assigning flt into int
+ // flt + int ==>> use float op, wrap toFloat()
+ // flt + flt ==>> use float op
+ Node op = switch(ch) {
+ case 1, (char)-1,
+ '+' -> new AddNode(lhs,rhs);
+ case '-' -> new SubNode(lhs,rhs);
+ case '*' -> new MulNode(lhs,rhs);
+ case '/' -> new DivNode(lhs,rhs);
+ default -> throw Utils.TODO();
+ };
+ // Convert to float ops, or narrow int types; error if not declared type.
+ // Also, if postfix LHS is still keep()
+ return liftExpr(peep(op.widen()),t,false);
+ }
+
+
+ // Expect an ID here. If not found, assume a forward reference function
+ Var requireLookupId() {
+ String id = _lexer.matchId();
+ if( id == null || KEYWORDS.contains(id) )
+ throw errorSyntax("an identifier or expression");
+ Var n = _scope.lookup(id);
+ // If missing, assume a forward reference
+ if( n==null ) {
+ _scope.define(id, FRefNode.FREF_TYPE, true, XCTRL, loc());
+ n = _scope.lookup(id);
+ } else {
+ // Lookup worked on an out-of-function value.
+ if( _scope.outOfFunction(n) ) {
+ // No closures, so this has to be a final constant (which
+ // includes forward refs)
+ Node def = _scope.in(n._idx);
+ if( !(def instanceof FRefNode) && !(n._final && def._type.isConstant()) )
+ throw error("Variable '"+n._name+"' is out of function scope and must be a final constant");
+ }
+ }
+ return n;
+ }
+
+ /**
+ Parse an allocation
+ */
+ private Node alloc() {
+ Type t = type();
+ if( t==null ) throw error("Expected a type");
+ // Parse ary[ length_expr ]
+ if( match("[") ) {
+ if( !t.makeZero().isa(t) )
+ throw error("Cannot allocate a non-nullable, since arrays always zero/null fill");
+ Node len = parseAsgn();
+ if( !(len._type instanceof TypeInteger) )
+ throw error("Cannot allocate an array with length "+len._type);
+ require("]");
+ TypeMemPtr tmp = typeAry(t);
+ return newArray(tmp._obj,len);
+ }
+
+ if( !(t instanceof TypeMemPtr tmp) )
+ throw error("Cannot allocate a "+t.str());
+
+ // Parse new struct { default_initialization }
+ StructNode s = INITS.get(tmp._obj._name);
+ if( s==null ) throw error("Unknown struct type '" + tmp._obj._name + "'");
+
+ Field[] fs = s._ts._fields;
+ // if the object is fully initialized, we can skip a block here.
+ // Check for constructor block:
+ boolean hasConstructor = match("{");
+ Ary<Node> init=s._inputs; int idx=0;
+ if( hasConstructor ) {
+ idx = _scope.nIns();
+ // Push a scope, and pre-assign all struct fields.
+ _scope.push(ScopeNode.Kind.Block);
+ Lexer loc = loc();
+ for( int i=0; i<fs.length; i++ )
+ _scope.define(fs[i]._fname, fs[i]._type, fs[i]._final, s.in(i)._type==Type.TOP ? con(Type.BOTTOM) : s.in(i), loc);
+ // Parse the constructor body
+ require(parseBlock(ScopeNode.Kind.Constructor),"}");
+ init = _scope._inputs;
+ }
+ // Check that all fields are initialized
+ for( int i=idx; i<init.size(); i++ )
+ if( init.at(i)._type == Type.TOP || init.at(i)._type == Type.BOTTOM )
+ throw error("'"+tmp._obj._name+"' is not fully initialized, field '" + fs[i-idx]._fname + "' needs to be set in a constructor");
+ Node ptr = newStruct(tmp._obj, con(tmp._obj.offset(fs.length)), idx, init );
+ if( hasConstructor )
+ _scope.pop();
+ return ptr;
+ }
+
+
+ /**
+ * Return a NewNode initialized memory.
+ * @param obj is the declared type, with GLB fields
+ * @param init is a collection of initialized fields
+ */
+ private Node newStruct( TypeStruct obj, Node size, int idx, Ary<Node> init ) {
+ Field[] fs = obj._fields;
+ if( fs==null )
+ throw error("Unknown struct type '" + obj._name + "'");
+ int len = fs.length;
+ Node[] ns = new Node[2+len];
+ ns[0] = ctrl(); // Control in slot 0
+ // Total allocated length in bytes
+ ns[1] = size;
+ // Memory aliases for every field
+ for( int i = 0; i < len; i++ )
+ ns[2+i] = memAlias(fs[i]._alias);
+ Node nnn = new NewNode(TypeMemPtr.make(obj), ns).peephole().keep();
+ for( int i = 0; i < len; i++ )
+ memAlias(fs[i]._alias, new ProjNode(nnn,i+2,memName(fs[i]._alias)).peephole());
+ Node ptr = new ProjNode(nnn.unkeep(),1,obj._name).peephole().keep();
+
+ // Initial nonzero values for every field
+ for( int i = 0; i < len; i++ ) {
+ Node val = init.get( i + idx );
+ if( val._type != val._type.makeZero() ) {
+ Node mem = memAlias(fs[i]._alias);
+ Node st = new StoreNode(loc(),fs[i]._fname,fs[i]._alias,fs[i]._type,mem,ptr,con(obj.offset(i)),val,true).peephole();
+ memAlias(fs[i]._alias,st);
+ }
+ }
+
+ return ptr.unkeep();
+ }
+
+ private static final Ary<Node> ALTMP = new Ary<>(Node.class);
+ private Node newArray(TypeStruct ary, Node len) {
+ int base = ary.aryBase ();
+ int scale= ary.aryScale();
+ Node size = peep(new AddNode(con(base),peep(new ShlNode(null,len.keep(),con(scale)))));
+ ALTMP.clear(); ALTMP.add(len.unkeep()); ALTMP.add(con(ary._fields[1]._type.makeZero()));
+ return newStruct(ary,size,0,ALTMP);
+ }
+
+ // We set up memory aliases by inserting special vars in the scope these
+ // variables are prefixed by $ so they cannot be referenced in Simple code.
+ // Using vars has the benefit that all the existing machinery of scoping
+ // and phis work as expected
+ private Node memAlias(int alias ) { return _scope.mem(alias ); }
+ private void memAlias(int alias, Node st) { _scope.mem(alias, st); }
+ public static String memName(int alias) { return ("$"+alias).intern(); }
+
+ /**
+ * Parse postfix expression; this can be a field expression, an array
+ * lookup or a postfix operator like '#'
+ *
+ * <pre>
+ * expr ('.' FIELD)* [ = expr ] // Field reference
+ * expr '#' // Postfix unary read operator
+ * expr ['++' | '--' ] // Postfix unary write operator
+ * expr ('[' expr ']')* = [ = expr ] // Array reference
+ * expr '(' [args,]* ')' // Function call
+ * </pre>
+ */
+ private Node parsePostfix(Node expr) {
+ String name;
+ if( match(".") ) name = requireId();
+ else if( match("#") ) name = "#";
+ else if( match("[") ) name = "[]";
+ else if( match("(") ) return parsePostfix(require(functionCall(expr),")"));
+ else return expr; // No postfix
+
+ if( expr._type==Type.NIL )
+ throw error("Accessing unknown field '" + name + "' from 'null'");
+
+ // Sanity check expr for being a reference
+ if( !(expr._type instanceof TypeMemPtr ptr) ) {
+ throw error( "Expected "+(name=="#" || name=="[]" ? "array" : "reference")+" but found " + expr._type.str() );
+ }
+
+ // Sanity check field name for existing
+ TypeMemPtr tmp = (TypeMemPtr)TYPES.get(ptr._obj._name);
+ if( tmp == null ) throw error("Accessing unknown field '" + name + "' from '" + ptr + "'");
+ TypeStruct base = tmp._obj;
+ int fidx = base.find(name);
+ if( fidx == -1 ) throw error("Accessing unknown field '" + name + "' from '" + ptr.str() + "'");
+
+ // Get field type and layout offset from base type and field index fidx
+ Field f = base._fields[fidx]; // Field from field index
+ Type tf = f._type;
+ if( tf instanceof TypeMemPtr ftmp && ftmp.isFRef() )
+ tf = ftmp.makeFrom(((TypeMemPtr)(TYPES.get(ftmp._obj._name)))._obj);
+
+ // Field offset; fixed for structs, computed for arrays
+ Node off = (name.equals("[]") // If field is an array body
+ // Array index math
+ ? peep(new AddNode(con(base.aryBase()),peep(new ShlNode(null,require(parseAsgn(),"]"),con(base.aryScale())))))
+ // Struct field offsets are hardwired
+ : con(base.offset(fidx))).keep();
+
+ // Disambiguate "obj.fld==x" boolean test from "obj.fld=x" field assignment
+ if( matchOpx('=','=') ) {
+ Node val = parseAsgn().keep();
+ Node lift = liftExpr( val, tf, f._final );
+
+ Node st = new StoreNode(loc(), name, f._alias, tf, memAlias(f._alias), expr, off.unkeep(), lift, false);
+ // Arrays include control, as a proxy for a safety range check.
+ // Structs don't need this; they only need a NPE check which is
+ // done via the type system.
+ if( base.isAry() ) st.setDef(0,ctrl());
+ memAlias(f._alias, st.peephole());
+ return val.unkeep(); // "obj.a = expr" returns the expression while updating memory
+ }
+
+ Node load = new LoadNode(loc(),name, f._alias, tf, memAlias(f._alias), expr.keep(), off);
+ // Arrays include control, as a proxy for a safety range check
+ // Structs don't need this; they only need a NPE check which is
+ // done via the type system.
+ if( base.isAry() && !name.equals("#") ) load.setDef(0,ctrl());
+ load = peep(load);
+
+ // Check for assign-update, "ptr.fld += expr" or "ary[idx]++"
+ char ch = _lexer.matchOperAssign();
+ if( ch!=0 ) {
+ Node op = opAssign(ch,load,f._final,tf,name);
+ Node st = new StoreNode(loc(), name, f._alias, tf, memAlias(f._alias), expr.unkeep(), off, op, false);
+ // Arrays include control, as a proxy for a safety range check.
+ // Structs don't need this; they only need a NPE check which is
+ // done via the type system.
+ if( base.isAry() ) st.setDef(0,ctrl());
+ memAlias(f._alias, peep(st));
+ load = postfix(ch) ? load.unkeep() : op;
+ // And use the original loaded value as the result
+ } else expr.unkill();
+ off.unkill();
+
+ return parsePostfix(load);
+ }
+
+
+ // zero/sign extend. "i" is limited to either classic unsigned (min==0) or
+ // classic signed (min=minus-power-of-2); max=power-of-2-minus-1.
+ private Node zsMask(Node val, Type t ) {
+ if( !(val._type instanceof TypeInteger tval && t instanceof TypeInteger t0 && !tval.isa(t0)) ) {
+ if( !(val._type instanceof TypeFloat tval && t instanceof TypeFloat t0 && !tval.isa(t0)) )
+ return val;
+ // Float rounding
+ return peep(new RoundF32Node(val));
+ }
+ if( t0._min==0 ) // Unsigned
+ return peep(new AndNode(null,val,con(t0._max)));
+ // Signed extension
+ int shift = Long.numberOfLeadingZeros(t0._max)-1;
+ Node shf = con(shift);
+ if( shf._type==TypeInteger.ZERO )
+ return val;
+ return peep(new SarNode(null,peep(new ShlNode(null,val,shf.keep())),shf.unkeep()));
+ }
+
+ /**
+ * Parse a function body; the caller will parse the surrounding "{}"
+ *
+ * <pre>
+ * { [type arg,]* -> expr }
+ * { expr } // The no-argument function
+ * </pre>
+ */
+ private Node func() {
+ Ary<Type> ts = new Ary<>(Type.class);
+ Ary<String> ids = new Ary<>(String.class);
+ _lexer.skipWhiteSpace();
+ Lexer loc = loc(); // First argument location
+ while( true ) {
+ Type t = type(); // Arg type
+ if( t==null ) break;
+ String id = requireId();
+ ts .push(t ); // Push type/arg pairs
+ ids.push(id);
+ match(",");
+ }
+ require("->");
+ // Make a concrete function type, with a fidx
+ TypeFunPtr tfp = _code.makeFun(TypeTuple.make(ts.asAry()),Type.BOTTOM);
+ ReturnNode ret = parseFunctionBody(tfp,loc,ids.asAry());
+ return con(ret._fun.sig());
+ }
+
+ /**
+ * Parse function call arguments; caller will parse the surrounding "()"
+ * <pre>
+ * ( arg* )
+ * </pre>
+ */
+ private Node functionCall(Node expr) {
+ if( expr._type == Type.NIL )
+ throw error("Calling a null function pointer");
+ if( !(expr instanceof FRefNode) && !expr._type.isa(TypeFunPtr.BOT) )
+ throw error("Expected a function but got "+expr._type.glb().str());
+ expr.keep(); // Keep while parsing args
+
+ Ary<Node> args = new Ary<Node>(Node.class);
+ args.push(null); // Space for ctrl,mem
+ args.push(null);
+ while( !peek(')') ) {
+ Node arg = parseAsgn();
+ if( arg==null ) break;
+ args.push(arg.keep());
+ if( !match(",") ) break;
+ }
+ // Control & memory after parsing args
+ args.set(0,ctrl().keep());
+ args.set(1,_scope.mem().merge().keep());
+ args.push(expr); // Function pointer
+ // Unkeep them all
+ for( Node arg : args )
+ arg.unkeep();
+ // Dead into the call? Skip all the node gen
+ if( ctrl()._type == Type.XCONTROL ) {
+ for( Node arg : args )
+ if( arg.isUnused() )
+ arg.kill();
+ return con(Type.TOP);
+ }
+
+ // Into the call
+ CallNode call = (CallNode)new CallNode(loc(), args.asAry()).peephole();
+
+ // Post-call setup
+ CallEndNode cend = (CallEndNode)new CallEndNode(call).peephole();
+ // Control from CallEnd
+ ctrl(new CProjNode(cend,0,ScopeNode.CTRL).peephole());
+ // Memory from CallEnd
+ MemMergeNode mem = new MemMergeNode(true);
+ mem.addDef(null); // Alias#0
+ mem.addDef(new ProjNode(cend,1,ScopeNode.MEM0).peephole());
+ _scope.mem(mem);
+ // Call result
+ return new ProjNode(cend,2,null).peephole();
+ }
+
+ /**
+ * Parse integer literal
+ *
+ * <pre>
+ * integerLiteral: [1-9][0-9]* | [0]
+ * floatLiteral: [digits].[digits]?[e [digits]]?
+ * </pre>
+ */
+ private ConstantNode parseLiteral() { return con(_lexer.parseNumber()); }
+ public static Node con( long con ) { return con==0 ? ZERO : con(TypeInteger.constant(con)); }
+ public static ConstantNode con( Type t ) { return (ConstantNode)new ConstantNode(t).peephole(); }
+ public Node peep( Node n ) {
+ // Peephole, then improve with lexically scoped guards
+ return _scope.upcastGuard(n.peephole());
+ }
+
+ //////////////////////////////////
+ // Utilities for lexical analysis
+
+ // Return true and skip if "syntax" is next in the stream.
+ private boolean match (String syntax) { return _lexer.match (syntax); }
+ // Match must be "exact", not be followed by more id letters
+ private boolean matchx(String syntax) { return _lexer.matchx(syntax); }
+ private boolean matchOpx(char c0, char c1) { return _lexer.matchOpx(c0,c1); }
+ // Return true and do NOT skip if 'ch' is next
+ private boolean peek(char ch) { return _lexer.peek(ch); }
+ private boolean peekIsId() { return _lexer.peekIsId(); }
+
+ // ch is +/- 1, means oper++ or oper-- means postfix
+ private static boolean postfix(char ch) {
+ return (byte)ch== 1 || (byte)ch== -1;
+ }
+
+ public int pos() { return _lexer._position; }
+ private int pos(int pos) {
+ int old = _lexer._position;
+ _lexer._position = pos;
+ return old;
+ }
+ private Type posT(int pos) { _lexer._position = pos; return null; }
+ // Source code location
+ Lexer loc() { return new Lexer(_lexer); }
+
+
+ // Require and return an identifier
+ private String requireId() {
+ String id = _lexer.matchId();
+ if (id != null && !KEYWORDS.contains(id) ) return id.intern();
+ throw error("Expected an identifier, found '"+id+"'");
+ }
+
+ private String matchId() {
+ int old = pos();
+ String id = _lexer.matchId();
+ if( id==null ) return null;
+ if( !KEYWORDS.contains(id) ) return id;
+ pos(old);
+ return null;
+ }
+
+ // Require an exact match
+ private Parser require(String syntax) { require(null, syntax); return this; }
+ private <N> N require(N n, String syntax) {
+ if (match(syntax)) return n;
+ throw errorSyntax(syntax);
+ }
+
+ ////////////////////////////////////
+ // Lexer components
+
+ // Lexer provides low level access to the raw file bytes, peeks and matches
+ // short strings, parses numbers, skips comments and whitespace, tracks
+ // line numbers, allows the parse position to be saved and restored, and
+ // serves as a location indicator for errors.
+
+ public static class Lexer {
+
+ // Input buffer; an array of text bytes read from a file or a string
+ private final byte[] _input;
+ // Tracks current position in input buffer
+ private int _position = 0;
+
+ //
+ private int _line_number = 1;
+ // Start of current line
+ private int _line_start = 0;
+
+ /**
+ * Record the source text for lexing
+ */
+ public Lexer(String source) {
+ this(source.getBytes());
+ }
+
+ /**
+ * Direct from disk file source
+ */
+ public Lexer(byte[] buf) {
+ _input = buf;
+ }
+
+ /**
+ * Copy a lexer from a lexer
+ */
+ private Lexer(Lexer l) {
+ _input = l._input;
+ _position = l._position;
+ _line_number = l._line_number;
+ _line_start = l._line_start;
+ }
+
+ // Very handy in the debugger, shows the unparsed program
+ @Override
+ public String toString() {
+ return new String(_input, _position, _input.length - _position);
+ }
+
+ // True if at EOF
+ private boolean isEOF() {
+ return _position >= _input.length;
+ }
+
+ // Peek next character, or report EOF
+ private char peek() {
+ return isEOF() ? Character.MAX_VALUE // Special value that causes parsing to terminate
+ : (char) _input[_position];
+ }
+ // Just crash if misused
+ public byte peek(int off) { return _input[_position+off]; }
+
+ private void inc() {
+ if( _position++ < _input.length && _input[_position-1] == '\n' ) {
+ _line_number++;
+ _line_start = _position;
+ }
+ }
+ // Does not honor LF, so caller must roll back position on a LF
+ private char nextChar() {
+ char ch = peek();
+ inc();
+ return ch;
+ }
+
+ // True if a white space
+ private boolean isWhiteSpace() {
+ return peek() <= ' '; // Includes all the use space, tab, newline, CR
+ }
+
+ /**
+ * Return the next non-white-space character
+ */
+ private void skipWhiteSpace() {
+ while( true ) {
+ if( isWhiteSpace() ) inc();
+ // Skip // to end of line
+ else if( _position+2 < _input.length &&
+ _input[_position ] == '/' &&
+ _input[_position+1] == '/') {
+ inc(); inc();
+ while( !isEOF() && _input[_position] != '\n' ) inc();
+ } else break;
+ }
+ }
+
+ // Next non-white-space character, or EOF
+ public char nextXChar() { skipWhiteSpace(); return nextChar(); }
+
+ // Return true, if we find "syntax" after skipping white space; also
+ // then advance the cursor past syntax.
+ // Return false otherwise, and do not advance the cursor.
+ boolean match(String syntax) {
+ assert syntax.indexOf('\n')==-1; // No newlines in match
+ skipWhiteSpace();
+ int len = syntax.length();
+ if (_position + len > _input.length) return false;
+ for (int i = 0; i < len; i++)
+ if ((char) _input[_position + i] != syntax.charAt(i))
+ return false;
+ _position += len;
+ return true;
+ }
+
+ // Match must be exact and not followed by more ID characters.
+ // Prevents identifier "ifxy" from matching an "if" statement.
+ boolean matchx(String syntax) {
+ if( !match(syntax) ) return false;
+ if( !isIdLetter(peek()) ) return true;
+ _position -= syntax.length();
+ return false;
+ }
+ boolean matchOpx(char c0, char c1) {
+ skipWhiteSpace();
+ if( _position+1 >= _input.length || _input[_position]!=c0 || _input[_position+1]==c1 )
+ return false;
+ inc();
+ return true;
+ }
+
+ private boolean peek(char ch) {
+ skipWhiteSpace();
+ return peek()==ch;
+ }
+
+ boolean peekIsId() {
+ skipWhiteSpace();
+ return isIdStart(peek());
+ }
+
+ // Return an identifier or null
+ String matchId() {
+ return peekIsId() ? parseId() : null;
+ }
+
+ // Used for errors
+ String getAnyNextToken() {
+ if (isEOF()) return "";
+ if (isIdStart(peek())) return parseId();
+ if (isNumber(peek())) return parseNumberString();
+ if (isPunctuation(peek())) return parsePunctuation();
+ return String.valueOf(peek());
+ }
+
+
+ boolean isNumber(char ch) {return Character.isDigit(ch);}
+
+ // Return a constant Type, either TypeInteger or TypeFloat
+ private Type parseNumber() {
+ int old = _position;
+ int len = isLongOrDouble();
+ if( len > 0 ) {
+ if( len > 1 && _input[old]=='0' )
+ throw error("Syntax error: integer values cannot start with '0'",this);
+ long i = Long.parseLong(new String(_input,old,len));
+ return TypeInteger.constant(i);
+ }
+ return TypeFloat.constant(Double.parseDouble(new String(_input,old,-len)));
+ }
+ private String parseNumberString() {
+ int old = _position;
+ int len = Math.abs(isLongOrDouble());
+ return new String(_input,old,len);
+ }
+
+ // Return +len that ends a long
+ // Return -len that ends a double
+ private int isLongOrDouble() {
+ int old = _position;
+ char c;
+ while( Character.isDigit(c=nextChar()) ) ;
+ if( !(c=='e' || c=='.') )
+ return --_position - old;
+ while( Character.isDigit(c=nextChar()) || c=='e' || c=='.' ) ;
+ return -(--_position - old);
+ }
+
+ // First letter of an identifier
+ private boolean isIdStart(char ch) {
+ return Character.isAlphabetic(ch) || ch == '_';
+ }
+
+ // All characters of an identifier, e.g. "_x123"
+ private boolean isIdLetter(char ch) {
+ return Character.isLetterOrDigit(ch) || ch == '_';
+ }
+
+ private String parseId() {
+ int start = _position;
+ while (isIdLetter(nextChar())) ;
+ return new String(_input, start, --_position - start);
+ }
+
+ //
+ private boolean isPunctuation(char ch) {
+ return "=;[]<>()+-/*&|^".indexOf(ch) != -1;
+ }
+
+ private String parsePunctuation() {
+ int start = _position;
+ return new String(_input, start, 1);
+ }
+
+ // Next oper= character, or 0.
+ // As a convenience, mark "++" as a char 1 and "--" as char -1 (65535)
+ public char matchOperAssign() {
+ skipWhiteSpace();
+ if( _position+2 >= _input.length ) return 0;
+ char ch0 = (char)_input[_position];
+ if( "+-/*&|^".indexOf(ch0) == -1 ) return 0;
+ char ch1 = (char)_input[_position+1];
+ if( ch1 == '=' ) { _position += 2; return ch0; }
+ if( isIdLetter((char)_input[_position+2]) ) return 0;
+ if( ch0 == '+' && ch1 == '+' ) { _position += 2; return (char) 1; }
+ if( ch0 == '-' && ch1 == '-' ) { _position += 2; return (char)-1; }
+ return 0;
+ }
+ }
+
+ ParseException errorSyntax(String syntax) { return _errorSyntax("expected "+syntax); }
+ private ParseException _errorSyntax(String msg) {
+ return error("Syntax error, "+msg+": " + _lexer.getAnyNextToken());
+ }
+ ParseException error(String msg) { return error(msg,_lexer); }
+ public static ParseException error(String msg, Lexer loc) { return new ParseException(msg,loc); }
+
+ public static class ParseException extends RuntimeException {
+ public final Lexer _loc;
+ // file:line:charoff err
+ //String msg = "src:"+_line_number+":"+(_position-_line_start)+" "+errorMessage;
+ ParseException( String msg, Lexer loc ) { super(msg); _loc = loc; assert loc!=null; }
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/RegMask.java b/chapter20/src/main/java/com/seaofnodes/simple/RegMask.java
new file mode 100644
index 00000000..20be7157
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/RegMask.java
@@ -0,0 +1,39 @@
+package com.seaofnodes.simple;
+
+import java.util.BitSet;
+
+// A "register mask" - 1 bit set for each allowed register. In addition "stack
+// slot" registers may be allowed, effectively making the set infinite.
+public class RegMask {
+
+ public static final RegMask EMPTY = new RegMask();
+
+ final BitSet _bits;
+
+ public RegMask(long x ) { _bits = BitSet.valueOf(new long[]{x}); }
+ public RegMask(long[] xs) { _bits = BitSet.valueOf( xs); }
+ // Internal constructor
+ RegMask() { _bits = new BitSet(); }
+ RegMask(BitSet bs) { _bits = bs; }
+
+ public boolean get(int r) { return _bits.get(r); }
+
+ // Defensive writable copy
+ public RegMaskRW copy() { return new RegMaskRW( (BitSet)_bits.clone() ); }
+
+ boolean size1() { return _bits.cardinality()==1; }
+}
+
+class RegMaskRW extends RegMask {
+ public RegMaskRW() { super(); }
+ public RegMaskRW(long x) { super(new long[]{x}); }
+ public RegMaskRW(long[] xs) { super(xs); }
+ public RegMaskRW(BitSet bs) { super(bs); }
+ public void set(int r) { _bits.set(r); }
+ public void clr(int r) { _bits.clear(r); }
+ public void set(int r, boolean b) { _bits.set(r,b); }
+ public RegMaskRW and( RegMask r ) {
+ _bits.and(r._bits);
+ return this;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/SB.java b/chapter20/src/main/java/com/seaofnodes/simple/SB.java
new file mode 100644
index 00000000..7d580c21
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/SB.java
@@ -0,0 +1,91 @@
+package com.seaofnodes.simple;
+
+/** Tight/tiny StringBuilder wrapper.
+ * Short short names on purpose; so they don't obscure the printing.
+ * Can't believe this wasn't done long, long ago. */
+public final class SB {
+ private final StringBuilder _sb;
+ private int _indent = 0;
+ public SB( ) { _sb = new StringBuilder( ); }
+ public SB(String s) { _sb = new StringBuilder(s); }
+ public SB p( String s ) { _sb.append(s); return this; }
+ public SB p( float s ) {
+ if( Float.isNaN(s) )
+ _sb.append( "Float.NaN");
+ else if( Float.isInfinite(s) ) {
+ _sb.append(s > 0 ? "Float.POSITIVE_INFINITY" : "Float.NEGATIVE_INFINITY");
+ } else _sb.append(s);
+ return this;
+ }
+ public SB p( double s ) {
+ if( Double.isNaN(s) )
+ _sb.append("Double.NaN");
+ else if( Double.isInfinite(s) ) {
+ _sb.append(s > 0 ? "Double.POSITIVE_INFINITY" : "Double.NEGATIVE_INFINITY");
+ } else _sb.append(s);
+ return this;
+ }
+ public SB p( char s ) { _sb.append(s); return this; }
+ public SB p( int s ) { _sb.append(s); return this; }
+ public SB p( long s ) { _sb.append(s); return this; }
+ public SB p( boolean s) { _sb.append(s); return this; }
+ // 4 hex digits
+ public SB hex4(int s) {
+ assert (s>>4*4)==0; // Fits in 16 bits
+ for( int i=0; i<4; i++ ) {
+ int digit = (s>>((3-i)*4)) & 0xf;
+ _sb.append((char)((digit <= 9 ? '0' : ('A'-10))+digit));
+ }
+ return this;
+ }
+ // Fixed width field
+ public SB fix( int sz, String s ) {
+ assert sz >=0;
+ for( int i=0; i<sz; i++ )
+ _sb.append( i < s.length() ? s.charAt(i) : ' ');
+ return this;
+ }
+
+ // Not spelled "p" on purpose: too easy to accidentally say "p(1.0)" and
+ // suddenly call the autoboxed version.
+ public SB pobj( Object s ) { _sb.append(s.toString()); return this; }
+ public SB i( int d ) { for( int i=0; i<d+_indent; i++ ) p(" "); return this; }
+ public SB i( ) { return i(0); }
+ public SB ip(String s) { return i().p(s); }
+ public SB s() { _sb.append(' '); return this; }
+
+ // Increase indentation
+ public SB ii( int i) { _indent += i; return this; }
+ public SB ii() { return ii(1); }
+ // Decrease indentation
+ public SB di( int i) { _indent -= i; return this; }
+ public SB di() { return di(1); }
+
+ public SB nl( ) { return p(System.lineSeparator()); }
+ // Last printed a nl
+ public boolean was_nl() {
+ int len = _sb.length();
+ String nl = System.lineSeparator();
+ int nlen = nl.length();
+ if( len < nlen ) return false;
+ for( int i=0; i<nlen; i++ )
+ if( _sb.charAt(len-nlen+i)!=nl.charAt(i) )
+ return false;
+ return true;
+ }
+
+ // Delete last char. Useful when doing string-joins and JSON printing and an
+ // extra separater char needs to be removed:
+ //
+ // sb.p('[');
+ // for( Foo foo : foos )
+ // sb.p(foo).p(',');
+ // sb.unchar().p(']'); // remove extra trailing comma
+ //
+ public SB unchar() { return unchar(1); }
+ public SB unchar(int x) { _sb.setLength(_sb.length()-x); return this; }
+
+ public SB clear() { _sb.setLength(0); return this; }
+ public int len() { return _sb.length(); }
+ @Override public String toString() { return _sb.toString(); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/SimpleWebSocket.java b/chapter20/src/main/java/com/seaofnodes/simple/SimpleWebSocket.java
new file mode 100644
index 00000000..1ce766ff
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/SimpleWebSocket.java
@@ -0,0 +1,148 @@
+package com.seaofnodes.simple;
+
+import java.io.*;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.net.URI;
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.util.Base64;
+
+// Why-Oh-Why is this needed?
+
+// Pass in a URI and a port.
+// Opens the client; client has to open a websocket at the given port.
+// Connects, handshakes.
+// Thereafter you can call get/put to swap frames with client.
+
+class SimpleWebSocket extends ServerSocket {
+ final InputStream _in;
+ final OutputStream _out;
+
+ SimpleWebSocket(URI uri, int port) throws IOException, NoSuchAlgorithmException {
+ super(port);
+ // Launch client
+ java.awt.Desktop.getDesktop().browse(uri);
+ // Look for client; get in/out streams
+ Socket sock = accept();
+ _in = sock. getInputStream();
+ _out = sock.getOutputStream();
+
+
+ // Establish web socket with handshake; easier with a buffered reader
+ BufferedReader br = new BufferedReader(new InputStreamReader(_in));
+ String key = null;
+ while( br.ready() ) {
+ String line = br.readLine();
+ if( line.startsWith("Sec-WebSocket-Key: ") )
+ key = line.substring(19);
+ }
+ assert key!=null;
+ // Magic handshake
+ byte[] response = ("HTTP/1.1 101 Switching Protocols\r\n"
+ + "Connection: Upgrade\r\n"
+ + "Upgrade: websocket\r\n"
+ + "Sec-WebSocket-Accept: "
+ + Base64.getEncoder().encodeToString(MessageDigest.getInstance("SHA-1").digest((key + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11").getBytes( StandardCharsets.UTF_8 )))
+ + "\r\n\r\n").getBytes( StandardCharsets.UTF_8 );
+ _out.write(response,0,response.length);
+ }
+
+ final byte[] _ins = new byte[1024];
+ final byte[] _str = new byte[1024];
+ final byte[] _key = new byte[4];
+ int _x, _len;
+ private int rawget() { assert _x<_len; return _ins[_x++]&0xFF; }
+
+ // TODO: Flip to Direct Byte Buffer, this is just a poor-mans version
+ private void flipRead() throws IOException {
+ // Move _x to _len to offset 0
+ System.arraycopy(_ins,_x,_ins,0,(_len-_x));
+ _len = _len-_x;
+ _x=0;
+ // Read more
+ int len = _in.read(_ins,_len,_ins.length-_len);
+ if( len == -1 )
+ throw Utils.TODO(); // EOF
+ _len += len;
+ }
+ // Block until you read at least len
+ private void atLeast(int len) throws IOException {
+ if( _x+len <= _len ) return;
+ flipRead();
+ }
+
+
+ // Classic read from browser client. Encoded, so decoded here
+ public String get() throws IOException {
+ atLeast(1); // Need 1 byte for opcode
+ int op = rawget();
+ if( (op&0x80)!=0x80 ) // FIN bit not set?
+ throw Utils.TODO( "Multi-part from client: " + op ); // Multipart message
+ op &= 0x7F; // Strip FIN bit
+ switch( op&15) {
+ case 1: {
+ atLeast(5); // Min message length
+ // Message length
+ int len = rawget()-128;
+ if( len > 125 ) {
+ if( len > 126 )
+ throw Utils.TODO(); // Multi-byte length
+ len = (rawget()<<8) | rawget();
+ }
+ atLeast(len+4); // Rest of message
+ // Encoding key
+ _key[0] = (byte)rawget();
+ _key[1] = (byte)rawget();
+ _key[2] = (byte)rawget();
+ _key[3] = (byte)rawget();
+
+ // Decode bytes
+ for( int i=0; i<len; i++ )
+ _str[i] = (byte)(rawget() ^ _key[i & 3]);
+
+ return new String(_str,0,len);
+ }
+ // Client closes
+ case 8: return null;
+ // Ping
+ case 9:
+ // Send a PONG back. TODO: echo PING data in the PONG
+ _out.write(0x8A); // FIN + PONG
+ _out.write(0x00); // LENGTH==0
+ return get();
+ // Not (yet) implemented: continuation frames, ping/pong
+ default:
+ throw Utils.TODO("Unexpected op from client: "+op); // Multi-part message
+ }
+ }
+
+ // Classic put to browser client. No encoding.
+ public void put(String msg) throws IOException {
+ int len = msg.length();
+ if( len <= 125 ) {
+ _out.write(129); // FIN, opcode 1 - whole text message
+ _out.write(len);
+ for( int i=0; i<msg.length(); i++ )
+ _out.write(msg.charAt(i));
+ return;
+ }
+ if( len > 65535 )
+ throw Utils.TODO("MOAR LENGTH");
+ _out.write(129); // FIN, opcode 1 - whole text message
+ _out.write(126); // Length is 16b
+ _out.write(len>>>8);
+ _out.write(len&255);
+ for( int i=0; i<msg.length(); i++ )
+ _out.write(msg.charAt(i));
+ }
+
+ @Override public void close() throws IOException {
+ if( _out != null ) {
+ _out.write(0b10001000);
+ _out.flush();
+ }
+ super.close();
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/Utils.java b/chapter20/src/main/java/com/seaofnodes/simple/Utils.java
new file mode 100644
index 00000000..1346c3ea
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/Utils.java
@@ -0,0 +1,53 @@
+package com.seaofnodes.simple;
+
+import java.util.ArrayList;
+
+public class Utils {
+ public static RuntimeException TODO() { return TODO("Not yet implemented"); }
+ public static RuntimeException TODO(String msg) { return new RuntimeException(msg); }
+
+ /**
+ * Fast, constant-time, element removal. Does not preserve order
+ *
+ * @param array ArrayList to modify
+ * @param i element to be removed
+ * @return element removed
+ */
+ public static <E> void del(ArrayList<E> array, int i) {
+ E last = array.removeLast();
+ if (i < array.size()) array.set(i, last);
+ }
+
+ /**
+ * Search a list for an element by reference
+ *
+ * @param ary List to search in
+ * @param x Object to be searched
+ * @return >= 0 on success, -1 on failure
+ */
+ public static <E> int find( ArrayList<E> ary, E x ) {
+ for( int i=0; i<ary.size(); i++ )
+ if( ary.get(i)==x )
+ return i;
+ return -1;
+ }
+ /**
+ * Search a list for an element by reference
+ *
+ * @param ary List to search in
+ * @param x Object to be searched
+ * @return >= 0 on success, -1 on failure
+ */
+ public static <E> int find( E[] ary, E x ) {
+ for( int i=0; i<ary.length; i++ )
+ if( ary[i]==x )
+ return i;
+ return -1;
+ }
+
+ // Rotate a long, nice for hashes
+ public static long rot( long x, int n ) { return (x<<n) | (x>>>n); }
+
+ // Fold a 64bit hash into 32 bits
+ public static int fold( long x ) { return (int)((x>>32) ^ x); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/Var.java b/chapter20/src/main/java/com/seaofnodes/simple/Var.java
new file mode 100644
index 00000000..e71d7ef2
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/Var.java
@@ -0,0 +1,55 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.type.*;
+
+
+/**
+ * The tracked fields are now complex enough to deserve a array-of-structs layout
+ */
+public class Var {
+
+ public final String _name; // Declared name
+ public int _idx; // index in containing scope
+ private Type _type; // Declared type
+ public boolean _final; // Final field
+ public Parser.Lexer _loc; // Source location
+ public boolean _fref; // Forward ref
+
+ public Var(int idx, String name, Type type, boolean xfinal, Parser.Lexer loc ) {
+ this(idx,name,type,xfinal,loc,false);
+ }
+ public Var(int idx, String name, Type type, boolean xfinal, Parser.Lexer loc, boolean fref) {
+ _idx = idx;
+ _name = name;
+ _type = type;
+ _final = xfinal;
+ _loc = loc;
+ _fref = fref;
+ }
+ public Type type() {
+ if( !_type.isFRef() ) return _type;
+ // Update self to no longer use the forward ref type
+ Type def = Parser.TYPES.get(((TypeMemPtr)_type)._obj._name);
+ return (_type=_type.meet(def));
+ }
+ public Type lazyGLB() {
+ Type t = type();
+ return t instanceof TypeMemPtr ? t : t.glb();
+ }
+
+ // Forward reference variables (not types) must be BOTTOM and
+ // distinct from inferred variables
+ public boolean isFRef() { return _fref; }
+
+ public void defFRef( Type type, boolean xfinal, Parser.Lexer loc ) {
+ assert isFRef() && xfinal;
+ _type = type;
+ _final = true;
+ _loc = loc;
+ _fref = false;
+ }
+
+ @Override public String toString() {
+ return _type.toString()+(_final ? " ": " !")+_name;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/AddFNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/AddFNode.java
new file mode 100644
index 00000000..7d4e2910
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/AddFNode.java
@@ -0,0 +1,44 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFloat;
+
+import java.util.BitSet;
+
+public class AddFNode extends Node {
+ public AddFNode(Node lhs, Node rhs) { super(null, lhs, rhs); }
+
+ @Override public String label() { return "AddF"; }
+
+ @Override public String glabel() { return "+"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append("+"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ if (in(1)._type instanceof TypeFloat i0 &&
+ in(2)._type instanceof TypeFloat i1) {
+ if (i0.isConstant() && i1.isConstant())
+ return TypeFloat.constant(i0.value()+i1.value());
+ }
+ return in(1)._type.meet(in(2)._type);
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Type t2 = in(2)._type;
+
+ // Add of 0.
+ if ( t2.isConstant() && t2 instanceof TypeFloat i && i.value()==0 )
+ return lhs;
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new AddFNode(lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/AddNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/AddNode.java
new file mode 100644
index 00000000..6b7f2418
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/AddNode.java
@@ -0,0 +1,190 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.*;
+
+import java.util.BitSet;
+
+import static com.seaofnodes.simple.Parser.con;
+
+public class AddNode extends Node {
+ public AddNode(Node lhs, Node rhs) { super(null, lhs, rhs); }
+
+ @Override public String label() { return "Add"; }
+
+ @Override public String glabel() { return "+"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append("+"), visited);
+ return sb.append(")");
+ }
+
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if( t1 instanceof TypeInteger i1 &&
+ t2 instanceof TypeInteger i2 ) {
+ if (i1.isConstant() && i2.isConstant())
+ return TypeInteger.constant(i1.value()+i2.value());
+ // Fold ranges like {0-1} + {2-3} into {2-4}.
+ if( !overflow(i1._min,i2._min) &&
+ !overflow(i1._max,i2._max) )
+ return TypeInteger.make(i1._min+i2._min,i1._max+i2._max);
+ }
+ return TypeInteger.BOT;
+ }
+
+ static boolean overflow( long x, long y ) {
+ if( (x ^ y ) < 0 ) return false; // unequal signs, never overflow
+ return (x ^ (x + y)) < 0; // sum has unequal signs, so overflow
+ }
+ @Override
+ public Node idealize () {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t2 = rhs._type;
+
+ // Add of 0. We do not check for (0+x) because this will already
+ // canonicalize to (x+0)
+ if( t2 == TypeInteger.ZERO )
+ return lhs;
+
+ // Add of same to a multiply by 2
+ if( lhs==rhs )
+ return new ShlNode(null,lhs,con(1));
+
+ // Goal: a left-spine set of adds, with constants on the rhs (which then fold).
+
+ // Move non-adds to RHS
+ if( !(lhs instanceof AddNode) && rhs instanceof AddNode )
+ return swap12();
+
+ // x+(-y) becomes x-y
+ if( rhs instanceof MinusNode minus )
+ return new SubNode(lhs,minus.in(1));
+
+ // Now we might see (add add non) or (add non non) or (add add add) but never (add non add)
+
+ // Do we have x + (y + z) ?
+ // Swap to (x + y) + z
+ // Rotate (add add add) to remove the add on RHS
+ if( rhs instanceof AddNode add )
+ return new AddNode(new AddNode(lhs,add.in(1)).peephole(), add.in(2));
+
+ // Now we might see (add add non) or (add non non) but never (add non add) nor (add add add)
+ if( !(lhs instanceof AddNode) )
+ // Rotate; look for (add (phi cons) con/(phi cons))
+ return spine_cmp(lhs,rhs,this) ? swap12() : phiCon(this,true);
+
+ // Now we only see (add add non)
+
+ // Dead data cycle; comes about from dead infinite loops. Do nothing,
+ // the loop will peep as dead after a bit.
+ if( lhs.in(1) == lhs )
+ return null;
+
+ // Do we have (x + con1) + con2?
+ // Replace with (x + (con1+con2) which then fold the constants
+ // lhs.in(2) is con1 here
+ // If lhs.in(2) is not a constant, we add ourselves as a dependency
+ // because if it later became a constant then we could make this
+ // transformation.
+ if( lhs.in(2).addDep(this)._type.isConstant() && rhs._type.isConstant() )
+ return new AddNode(lhs.in(1),new AddNode(lhs.in(2),rhs).peephole());
+
+
+ // Do we have ((x + (phi cons)) + con) ?
+ // Do we have ((x + (phi cons)) + (phi cons)) ?
+ // Push constant up through the phi: x + (phi con0+con0 con1+con1...)
+ Node phicon = phiCon(this,true);
+ if( phicon!=null ) return phicon;
+
+ // Now we sort along the spine via rotates, to gather similar things together.
+
+ // Do we rotate (x + y) + z
+ // into (x + z) + y ?
+ if( spine_cmp(lhs.in(2),rhs,this) )
+ return new AddNode(new AddNode(lhs.in(1),rhs).peephole(),lhs.in(2));
+
+ return null;
+ }
+
+ // Rotation is only valid for associative ops, e.g. Add, Mul, And, Or, Xor.
+ // Do we have ((phi cons)|(x + (phi cons)) + con|(phi cons)) ?
+ // Push constant up through the phi: x + (phi con0+con0 con1+con1...)
+ static Node phiCon(Node op, boolean rotate) {
+ Node lhs = op.in(1);
+ Node rhs = op.in(2);
+ if( rhs._type==TypeInteger.TOP ) return null;
+ // LHS is either a Phi of constants, or another op with Phi of constants
+ PhiNode lphi = pcon(lhs,op);
+ if( rotate && lphi==null && lhs.nIns() > 2 ) {
+ // Only valid to rotate constants if both are same associative ops
+ if( lhs.getClass() != op.getClass() ) return null;
+ lphi = pcon(lhs.in(2),op); // Will rotate with the Phi push
+ }
+ if( lphi==null ) return null;
+ if( lphi.region().nIns() <=2 ) return null; // Phi is collapsing
+
+ // RHS is a constant or a Phi of constants
+ if( !(rhs instanceof ConstantNode) && pcon(rhs,op)==null )
+ return null;
+
+ // If both are Phis, must be same Region
+ if( rhs instanceof PhiNode && lphi.in(0) != rhs.in(0) )
+ return null;
+
+ // Note that this is the exact reverse of Phi pulling a common op down
+ // to reduce total op-count. We don't get in an endless push-up
+ // push-down peephole cycle because the constants all fold first.
+ Node[] ns = new Node[lphi.nIns()];
+ ns[0] = lphi.in(0);
+ // Push constant up through the phi: x + (phi con0+con0 con1+con1...)
+ for( int i=1; i<ns.length; i++ )
+ ns[i] = op.copy(lphi.in(i), rhs instanceof PhiNode ? rhs.in(i) : rhs).peephole();
+ String label = lphi._label + (rhs instanceof PhiNode rphi ? rphi._label : "");
+ Node phi = new PhiNode(label,lphi._declaredType,ns).peephole();
+ // Rotate needs another op, otherwise just the phi
+ return lhs==lphi ? phi : op.copy(lhs.in(1),phi);
+ }
+
+ /**
+ * Tests if the op is a phi and has all constant inputs.
+ * If not, returns null.
+ * If op is a phi, but its inputs are not all constants, then dep is added as
+ * a dependency to the phi's non-const input, because if later the input turn into a constant
+ * dep can make progress.
+ */
+ static PhiNode pcon(Node op, Node dep) {
+ return op instanceof PhiNode phi && phi.allCons(dep) ? phi : null;
+ }
+
+ // Compare two off-spine nodes and decide what order they should be in.
+ // Do we rotate ((x + hi) + lo) into ((x + lo) + hi) ?
+ // Generally constants always go right, then Phi-of-constants, then muls, then others.
+ // Ties with in a category sort by node ID.
+ // TRUE if swapping hi and lo.
+ static boolean spine_cmp( Node hi, Node lo, Node dep ) {
+ if( lo._type.isConstant() ) return false;
+ if( hi._type.isConstant() ) return true ;
+
+ if( lo instanceof PhiNode lphi && lphi.region()._type==Type.XCONTROL ) return false;
+ if( hi instanceof PhiNode hphi && hphi.region()._type==Type.XCONTROL ) return false;
+
+ if( lo instanceof PhiNode && lo.allCons(dep) ) return false;
+ if( hi instanceof PhiNode && hi.allCons(dep) ) return true ;
+
+ if( lo instanceof PhiNode && !(hi instanceof PhiNode) ) return true;
+ if( hi instanceof PhiNode && !(lo instanceof PhiNode) ) return false;
+
+ // Same category of "others"
+ return lo._nid > hi._nid;
+ }
+
+ @Override Node copy(Node lhs, Node rhs) { return new AddNode(lhs,rhs); }
+ @Override Node copyF() { return new AddFNode(null,null); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/AndNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/AndNode.java
new file mode 100644
index 00000000..36e3a949
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/AndNode.java
@@ -0,0 +1,58 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+
+import java.util.BitSet;
+
+public class AndNode extends LogicalNode {
+ public AndNode(Parser.Lexer loc, Node lhs, Node rhs) { super(loc, lhs, rhs); }
+
+ @Override public String label() { return "And"; }
+ @Override public String op() { return "&"; }
+
+ @Override public String glabel() { return "&"; }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if( t1 instanceof TypeInteger i0 &&
+ t2 instanceof TypeInteger i1 ) {
+ if( i0.isConstant() && i1.isConstant() )
+ return TypeInteger.constant(i0.value()&i1.value());
+ // Sharpen allowed bits if either value is narrowed
+ long mask = i0.mask() & i1.mask();
+ return mask < 0 ? TypeInteger.BOT : TypeInteger.make(0,mask);
+ }
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t1 = lhs._type;
+ Type t2 = rhs._type;
+
+ // And of -1. We do not check for (-1&x) because this will already
+ // canonicalize to (x&-1)
+ if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==-1 )
+ return lhs;
+
+ // Move constants to RHS: con*arg becomes arg*con
+ if ( t1.isConstant() && !t2.isConstant() )
+ return swap12();
+
+ // Do we have ((x & (phi cons)) & con) ?
+ // Do we have ((x & (phi cons)) & (phi cons)) ?
+ // Push constant up through the phi: x & (phi con0&con0 con1&con1...)
+ Node phicon = AddNode.phiCon(this,true);
+ if( phicon!=null ) return phicon;
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new AndNode(_loc,lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/BoolNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/BoolNode.java
new file mode 100644
index 00000000..84be11a9
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/BoolNode.java
@@ -0,0 +1,134 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+import static com.seaofnodes.simple.type.TypeInteger.*;
+
+abstract public class BoolNode extends Node {
+
+ public BoolNode(Node lhs, Node rhs) {
+ super(null, lhs, rhs);
+ }
+
+ abstract public String op(); // String opcode name
+
+ @Override
+ public String label() { return getClass().getSimpleName(); }
+
+ @Override
+ public String glabel() { return op(); }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append(op()), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public TypeInteger compute() {
+ Type t1 = in(1)._type;
+ Type t2 = in(2)._type;
+ // Exactly equals?
+ if( t1.isHigh() || t2.isHigh() )
+ return BOOL.dual();
+ if( in(1)==in(2) )
+ // LT fails, both EQ and LE succeed
+ return this instanceof LT ? FALSE : TRUE;
+ if( t1 instanceof TypeInteger i1 &&
+ t2 instanceof TypeInteger i2 )
+ return doOp(i1,i2);
+ if( t1 instanceof TypeFloat f1 &&
+ t2 instanceof TypeFloat f2 &&
+ f1.isConstant() && f2.isConstant() )
+ return doOp(f1.value(), f2.value()) ? TRUE : FALSE;
+ return BOOL;
+ }
+
+ TypeInteger doOp(TypeInteger t1, TypeInteger t2) { throw Utils.TODO(); }
+ boolean doOp(double lhs, double rhs) { throw Utils.TODO(); }
+ Node copyF(Node lhs, Node rhs) { return null; }
+
+ @Override
+ public Node idealize() {
+ // Compare of same
+ if( in(1)==in(2) )
+ return this instanceof LT ? Parser.ZERO : new ConstantNode(TRUE);
+
+ // Equals pushes constant to the right; 5==X becomes X==5.
+ if( this instanceof EQ ) {
+ if( !(in(2) instanceof ConstantNode) ) {
+ // con==noncon becomes noncon==con
+ if( in(1) instanceof ConstantNode || in(1)._nid > in(2)._nid )
+ // Equals sorts by NID otherwise: non.high == non.low becomes non.low == non.high
+ return in(1)._type instanceof TypeFloat ? new EQF(in(2),in(1)) : new EQ(in(2),in(1));
+ }
+ // Equals X==0 becomes a !X
+ if( (in(2)._type == ZERO || in(2)._type == Type.NIL) )
+ return new NotNode(in(1));
+ }
+
+ // Do we have ((x * (phi cons)) * con) ?
+ // Do we have ((x * (phi cons)) * (phi cons)) ?
+ // Push constant up through the phi: x * (phi con0*con0 con1*con1...)
+ Node phicon = AddNode.phiCon(this,this instanceof EQ);
+ if( phicon!=null ) return phicon;
+
+ return null;
+ }
+
+ public static class EQ extends BoolNode {
+ public EQ(Node lhs, Node rhs) { super(lhs,rhs); }
+ public String op() { return "=="; }
+ TypeInteger doOp(TypeInteger i1, TypeInteger i2) {
+ if( i1==i2 && i1.isConstant() ) return TRUE;
+ if( i1._max < i2._min || i1._min > i2._max ) return FALSE;
+ return BOOL;
+ }
+ Node copy(Node lhs, Node rhs) { return new EQ(lhs,rhs); }
+ Node copyF() { return new EQF(null,null); }
+ }
+ public static class LT extends BoolNode {
+ public LT(Node lhs, Node rhs) { super(lhs,rhs); }
+ public String op() { return "<" ; }
+ public String glabel() { return "&lt;"; }
+ TypeInteger doOp(TypeInteger i1, TypeInteger i2) {
+ if( i1._max < i2._min ) return TRUE;
+ if( i1._min >= i2._max ) return FALSE;
+ return BOOL;
+ }
+ Node copy(Node lhs, Node rhs) { return new LT(lhs,rhs); }
+ Node copyF() { return new LTF(null,null); }
+ }
+ public static class LE extends BoolNode {
+ public LE(Node lhs, Node rhs) { super(lhs,rhs); }
+ public String op() { return "<="; }
+ public String glabel() { return "&lt;="; }
+ TypeInteger doOp(TypeInteger i1, TypeInteger i2) {
+ if( i1._max <= i2._min ) return TRUE;
+ if( i1._min > i2._max ) return FALSE;
+ return BOOL;
+ }
+ Node copy(Node lhs, Node rhs) { return new LE(lhs,rhs); }
+ Node copyF() { return new LEF(null,null); }
+ }
+
+ public static class EQF extends EQ { public EQF(Node lhs, Node rhs) { super(lhs,rhs); } boolean doOp(double lhs, double rhs) { return lhs == rhs; } }
+ public static class LTF extends LT { public LTF(Node lhs, Node rhs) { super(lhs,rhs); } boolean doOp(double lhs, double rhs) { return lhs < rhs; } }
+ public static class LEF extends LE { public LEF(Node lhs, Node rhs) { super(lhs,rhs); } boolean doOp(double lhs, double rhs) { return lhs <= rhs; } }
+
+ // Unsigned less that, for range checks. Not directly user writable.
+ public static class ULT extends BoolNode {
+ public ULT(Node lhs, Node rhs) { super(lhs,rhs); }
+ public String op() { return "u<" ; }
+ public String glabel() { return "u&lt;"; }
+ TypeInteger doOp(TypeInteger i1, TypeInteger i2) {
+ if( Long.compareUnsigned(i1._max,i2._min) < 0 ) return TRUE;
+ if( Long.compareUnsigned(i1._min,i2._max) >= 0 ) return FALSE;
+ return BOOL;
+ }
+ Node copy(Node lhs, Node rhs) { return new ULT(lhs,rhs); }
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/CFGNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/CFGNode.java
new file mode 100644
index 00000000..174725f5
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/CFGNode.java
@@ -0,0 +1,162 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Ary;
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+import java.util.HashMap;
+import java.util.HashSet;
+
+/** Control Flow Graph Nodes
+ * <p>
+ * CFG nodes have a immediate dominator depth (idepth) and a loop nesting
+ * depth(loop_depth).
+ * <p>
+ * idepth is computed lazily upon first request, and is valid even in the
+ * Parser, and is used by peepholes during parsing and afterward.
+ * <p>
+ * loop_depth is computed after optimization as part of scheduling.
+ *
+ */
+public abstract class CFGNode extends Node {
+
+ public CFGNode(Node... nodes) { super(nodes); }
+ public CFGNode(CFGNode cfg) {
+ super(cfg);
+ _idepth = cfg._idepth;
+ _ltree = cfg._ltree;
+ _pre = cfg._pre;
+ }
+
+ public CFGNode cfg(int idx) { return (CFGNode)in(idx); }
+
+ // Block head is Start, Region, CProj, but not e.g. If, Return, Stop
+ public boolean blockHead() { return false; }
+
+ // Get the one control following; error to call with more than one e.g. an
+ // IfNode or other multi-way branch.
+ public CFGNode uctrl() {
+ CFGNode c = null;
+ for( Node n : _outputs )
+ if( n instanceof CFGNode cfg )
+ { assert c==null; c = cfg; }
+ return c;
+ }
+
+
+ // ------------------------------------------------------------------------
+ /**
+ * Immediate dominator tree depth, used to approximate a real IDOM during
+ * parsing where we do not have the whole program, and also peepholes
+ * change the CFG incrementally.
+ * <p>
+ * See {@link <a href="https://en.wikipedia.org/wiki/Dominator_(graph_theory)">...</a>}
+ */
+ public int _idepth;
+ public int idepth() { return _idepth==0 ? (_idepth=idom().idepth()+1) : _idepth; }
+
+ // Return the immediate dominator of this Node and compute dom tree depth.
+ public CFGNode idom(Node dep) { return cfg(0); }
+ public final CFGNode idom() { return idom(null); }
+
+ // Return the LCA of two idoms
+ public CFGNode _idom(CFGNode rhs, Node dep) {
+ if( rhs==null ) return this;
+ CFGNode lhs = this;
+ while( lhs != rhs ) {
+ var comp = lhs.idepth() - rhs.idepth();
+ if( comp >= 0 ) lhs = ((CFGNode)lhs.addDep(dep)).idom();
+ if( comp <= 0 ) rhs = ((CFGNode)rhs.addDep(dep)).idom();
+ }
+ return lhs;
+ }
+
+ // Anti-dependence field support
+ public int _anti; // Per-CFG field to help find anti-deps
+
+ // ------------------------------------------------------------------------
+ // Loop nesting
+ public LoopNode loop() { return _ltree._head; }
+ public int loopDepth() { return _ltree==null ? 0 : _ltree.depth(); }
+
+ LoopTree _ltree;
+ int _pre; // Pre-order numbers for loop tree finding
+ private static class LoopTree {
+ LoopTree _par;
+ final LoopNode _head;
+ int _depth;
+ LoopTree(LoopNode head) { _head = head; }
+ @Override public String toString() { return "LOOP"+_head._nid; }
+ int depth() {
+ return _depth==0 ? (_par==null ? 0 : (_depth = _par.depth()+1)) : _depth;
+ }
+ }
+
+ // ------------------------------------------------------------------------
+ // Tag all CFG Nodes with their containing LoopNode; LoopNodes themselves
+ // also refer to *their* containing LoopNode, as well as have their depth.
+ // Start is a LoopNode which contains all at depth 1.
+ public void buildLoopTree(StopNode stop) {
+ _ltree = stop._ltree = Parser.XCTRL._ltree = new LoopTree((StartNode)this);
+ _bltWalk(2,null,stop, new BitSet());
+ }
+ int _bltWalk( int pre, FunNode fun, StopNode stop, BitSet post ) {
+ // Pre-walked?
+ if( _pre!=0 ) return pre;
+ _pre = pre++;
+ // Pre-walk
+ for( Node use : _outputs )
+ if( use instanceof CFGNode usecfg && !skip( usecfg ) )
+ pre = usecfg._bltWalk( pre, use instanceof FunNode fuse ? fuse : fun, stop, post );
+
+ // Post-order work: find innermost loop
+ LoopTree inner = null, ltree;
+ for( Node use : _outputs ) {
+ if( !(use instanceof CFGNode usecfg) ) continue;
+ if( skip(usecfg) ) continue;
+ if( usecfg._type == Type.XCONTROL || // Do not walk dead control
+ usecfg._type == TypeTuple.IF_NEITHER ) // Nor dead IFs
+ continue;
+ // Child visited but not post-visited?
+ if( !post.get(usecfg._nid) ) {
+ // Must be a backedge to a LoopNode then
+ ltree = usecfg._ltree = new LoopTree((LoopNode)usecfg);
+ } else {
+ // Take child's loop choice, which must exist
+ ltree = usecfg._ltree;
+ // If falling into a loop, use the target loop's parent instead
+ if( ltree._head == usecfg ) {
+ if( ltree._par == null )
+ // This loop never had an If test choose to take its
+ // exit, i.e. it is a no-exit infinite loop.
+ ltree._par = ltree._head.forceExit(fun,stop)._ltree;
+ ltree = ltree._par;
+ }
+ }
+ // Sort inner loops. The decision point is some branch far removed
+ // from either loop head OR either backedge so requires pre-order
+ // numbers to figure out innermost.
+ if( inner == null ) { inner = ltree; continue; }
+ if( inner == ltree ) continue; // No change
+ LoopTree outer = ltree._head._pre > inner._head._pre ? inner : ltree;
+ inner = ltree._head._pre > inner._head._pre ? ltree : inner;
+ inner._par = outer;
+ }
+ // Set selected loop
+ if( inner!=null )
+ _ltree = inner;
+ // Tag as post-walked
+ post.set(_nid);
+ return pre;
+ }
+
+ boolean skip(CFGNode usecfg) {
+ // Only walk control users that are alive.
+ // Do not walk from a Call to linked Fun's.
+ return usecfg instanceof XCtrlNode ||
+ (this instanceof CallNode && usecfg instanceof FunNode) ||
+ (this instanceof ReturnNode && usecfg instanceof CallEndNode);
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/CProjNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/CProjNode.java
new file mode 100644
index 00000000..690ef590
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/CProjNode.java
@@ -0,0 +1,62 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeMem;
+import com.seaofnodes.simple.type.TypeTuple;
+import java.util.BitSet;
+
+public class CProjNode extends CFGNode {
+
+ // Which slice of the incoming multipart value
+ public final int _idx;
+
+ // Debugging label
+ public final String _label;
+
+ public CProjNode(Node ctrl, int idx, String label) {
+ super(ctrl);
+ _idx = idx;
+ _label = label;
+ }
+ public CProjNode(CProjNode c) { super(c); _idx = c._idx; _label = c._label; }
+
+ @Override public String label() { return _label; }
+
+ @Override StringBuilder _print1(StringBuilder sb, BitSet visited) { return sb.append(_label); }
+
+ @Override public boolean isMultiTail() { return in(0).isMultiHead(); }
+ @Override public boolean blockHead() { return true; }
+
+ public CFGNode ctrl() { return cfg(0); }
+
+ @Override
+ public Type compute() {
+ Type t = ctrl()._type;
+ return t instanceof TypeTuple tt ? tt._types[_idx] : Type.BOTTOM;
+ }
+
+ @Override
+ public Node idealize() {
+ if( ctrl()._type instanceof TypeTuple tt ) {
+ if( tt._types[_idx]==Type.XCONTROL )
+ return Parser.XCTRL; // We are dead
+ if( ctrl() instanceof IfNode && tt._types[1-_idx]==Type.XCONTROL ) // Only true for IfNodes
+ return ctrl().in(0); // We become our input control
+ }
+
+ // Flip a negating if-test, to remove the not
+ if( ctrl() instanceof IfNode iff && iff.pred().addDep(this) instanceof NotNode not )
+ return new CProjNode(new IfNode(iff.ctrl(),not.in(1)).peephole(),1-_idx,_idx==0 ? "False" : "True");
+
+ // Copy of some other input
+ return ((MultiNode)ctrl()).pcopy(_idx);
+ }
+
+ @Override
+ boolean eq( Node n ) { return _idx == ((CProjNode)n)._idx; }
+
+ @Override
+ int hash() { return _idx; }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/CallEndNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/CallEndNode.java
new file mode 100644
index 00000000..4e50c1fc
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/CallEndNode.java
@@ -0,0 +1,90 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+
+/**
+ * CallEnd
+ */
+public class CallEndNode extends CFGNode implements MultiNode {
+
+ // When set true, this Call/CallEnd/Fun/Return is being trivially inlined
+ private boolean _folding;
+
+ public CallEndNode(CallNode call) { super(new Node[]{call}); }
+ public CallEndNode(CallEndNode cend) { super(cend); }
+
+ @Override
+ public String label() { return "CallEnd"; }
+ @Override public boolean isMultiHead() { return true; }
+ @Override public boolean blockHead() { return true; }
+
+ CallNode call() { return (CallNode)in(0); }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ sb.append("cend( ");
+ sb.append( in(0) instanceof CallNode ? "Call, " : "----, ");
+ for( int i=1; i<nIns()-1; i++ )
+ in(i)._print0(sb,visited).append(",");
+ sb.setLength(sb.length()-1);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ if( !(in(0) instanceof CallNode call) )
+ return TypeTuple.RET.dual();
+ Type ret = call.fptr().addDep(this)._type instanceof TypeFunPtr tfp ? tfp.ret() : Type.BOTTOM;
+ return TypeTuple.make(call._type,TypeMem.BOT,ret);
+ }
+
+ @Override
+ public Node idealize() {
+
+ // Trivial inlining: call site calls a single function; single function
+ // is only called by this call site.
+ if( !_folding && nIns()==2 && in(0) instanceof CallNode call ) {
+ Node fptr = call.fptr();
+ if( fptr.nOuts() == 1 && // Only user is this call
+ fptr instanceof ConstantNode && // We have an immediate call
+ // Function is being called, and its not-null
+ fptr._type instanceof TypeFunPtr tfp && tfp.notNull() &&
+ // Arguments are correct
+ call.err()==null ) {
+ ReturnNode ret = (ReturnNode)in(1);
+ FunNode fun = ret.fun();
+ // Expecting Start, and the Call
+ if( fun.nIns()==3 ) {
+ assert fun.in(1) instanceof StartNode && fun.in(2)==call;
+ // Disallow self-recursive inlining (loop unrolling by another name)
+ CFGNode idom = call;
+ while( !(idom instanceof FunNode fun2) )
+ idom = idom.idom();
+ if( idom != fun ) {
+ // Trivial inline: rewrite
+ _folding = true;
+ // Rewrite Fun so the normal RegionNode ideal collapses
+ fun._folding = true;
+ fun.setDef(1,Parser.XCTRL); // No default/unknown StartNode caller
+ fun.setDef(2,call.ctrl()); // Bypass the Call;
+ fun.ret().setDef(3,null); // Return is folding also
+ CodeGen.CODE.addAll(fun._outputs);
+ return this;
+ }
+ } else {
+ fun.addDep(this);
+ }
+ } else { // Function ptr has multiple users (so maybe multiple call sites)
+ fptr.addDep(this);
+ }
+ }
+
+ return null;
+ }
+
+ @Override public Node pcopy(int idx) {
+ return _folding ? in(1).in(idx) : null;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/CallNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/CallNode.java
new file mode 100644
index 00000000..a9ca852c
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/CallNode.java
@@ -0,0 +1,146 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.IterPeeps;
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFunPtr;
+import java.util.BitSet;
+
+/**
+ * Call
+ */
+public class CallNode extends CFGNode {
+
+ // Source location for late reported errors
+ public final Parser.Lexer _loc;
+
+ public CallNode(Parser.Lexer loc, Node... nodes) { super(nodes); _loc = loc; }
+ public CallNode(CallNode call) { super(call); _loc = call._loc; }
+
+ @Override
+ public String label() { return "Call"; }
+
+ @Override StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ String fname = name();
+ if( fname == null ) fptr()._print0(sb,visited);
+ else sb.append(fname);
+ sb.append("( ");
+ for( int i=2; i<nIns()-1; i++ )
+ in(i)._print0(sb,visited).append(",");
+ sb.setLength(sb.length()-1);
+ return sb.append(")");
+ }
+ public String name() {
+ if( fptr()._type instanceof TypeFunPtr tfp && tfp.isConstant() )
+ return CodeGen.CODE.link(tfp)._name;
+ return null;
+ }
+
+
+
+ Node ctrl() { return in(0); }
+ Node mem () { return in(1); }
+ // Args mapped 1-to-1 on inputs, so conceptually start at 2
+ Node arg(int idx) { return in(idx); }
+ // Same arg accounting as TFPs, although the numbering starts at 2
+ int nargs() { return nIns()-3; } // Minus control, memory, fptr
+ // args from input 2 to last; last is function input
+ public Node fptr() { return _inputs.last(); }
+
+ // Find the Call End from the Call
+ public CallEndNode cend() {
+ // Always in use slot 0
+ if( nOuts()>0 && out(0) instanceof CallEndNode cend ) {
+ assert _cend()==cend;
+ return cend;
+ } else {
+ assert _cend()==null;
+ return null;
+ }
+ }
+ private CallEndNode _cend() {
+ CallEndNode cend=null;
+ for( Node n : _outputs )
+ if( n instanceof CallEndNode cend0 )
+ { assert cend == null; cend = cend0; }
+ return cend;
+ }
+
+ // Get the one control following; error to call with more than one e.g. an
+ // IfNode or other multi-way branch.
+ @Override public CFGNode uctrl() { return cend(); }
+
+
+ @Override
+ public Type compute() {
+ return ctrl()._type;
+ }
+
+ @Override
+ public Node idealize() {
+ CallEndNode cend = cend();
+ if( cend==null ) return null; // Still building
+
+ // Link: call calls target function. Linking makes the target FunNode
+ // point to this Call, and all his Parms point to the call arguments;
+ // also the CallEnd points to the Return.
+ if( fptr()._type instanceof TypeFunPtr tfp && tfp.nargs() == nargs() ) {
+ // If fidxs is negative, then infinite unknown functions
+ long fidxs = tfp.fidxs();
+ if( fidxs > 0 ) {
+ // Wipe out the return which matching in the linker table
+ // Walk the (63 max) bits and link
+ for( ; fidxs!=0; fidxs = TypeFunPtr.nextFIDX(fidxs) ) {
+ int fidx = Long.numberOfTrailingZeros(fidxs);
+ TypeFunPtr tfp0 = tfp.makeFrom(fidx);
+ FunNode fun = CodeGen.CODE.link(tfp0);
+ if( fun!=null && !fun._folding && !linked(fun) )
+ link(fun);
+ }
+ }
+ }
+
+ return null;
+ }
+
+ // True if Fun is linked to this Call
+ boolean linked( FunNode fun ) {
+ for( Node n : fun._inputs )
+ if( n == this )
+ return true;
+ return false;
+ }
+
+
+ // Link so this calls fun
+ private void link( FunNode fun ) {
+ assert !linked(fun);
+ fun.addDef(this);
+ for( Node use : fun._outputs )
+ if( use instanceof ParmNode parm )
+ parm.addDef(parm._idx==0 ? cend() : arg(parm._idx));
+ // Call end points to function return
+ CodeGen.CODE.add(cend()).addDef(fun.ret());
+ assert linked(fun);
+ }
+
+ @Override
+ public Parser.ParseException err() {
+ if( !(fptr()._type instanceof TypeFunPtr tfp) )
+ throw Utils.TODO();
+ if( !tfp.notNull() )
+ return Parser.error( "Might be null calling "+tfp, _loc);
+ if( nargs() != tfp.nargs() )
+ return Parser.error( "Expecting "+tfp.nargs()+" arguments, but found "+nargs(), _loc);
+
+ // Check for args
+ for( int i=0; i<tfp.nargs(); i++ )
+ if( !arg(i+2)._type.isa(tfp.arg(i)) )
+ return Parser.error( "Argument #"+i+" isa "+arg(i+2)._type+", but must be a "+tfp.arg(i), _loc);
+
+ return null;
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/CastNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/CastNode.java
new file mode 100644
index 00000000..d8a968c1
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/CastNode.java
@@ -0,0 +1,58 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+// Upcast (join) the input to a t. Used after guard test to lift an input.
+// Can also be used to make a type-assertion if ctrl is null.
+public class CastNode extends Node {
+ private final Type _t;
+ public CastNode(Type t, Node ctrl, Node in) {
+ super(ctrl, in);
+ _t = t;
+ setType(compute());
+ }
+
+ @Override public String label() { return "("+_t.str()+")"; }
+
+ @Override
+ public String uniqueName() { return "Cast_" + _nid; }
+
+ @Override public boolean isPinned() { return true; }
+ @Override public boolean isConst() { return true; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ return in(1)._print0(sb.append(label()), visited);
+ }
+
+ @Override
+ public Type compute() {
+ return in(1)._type.join(_t);
+ }
+
+ @Override
+ public Node idealize() {
+ return in(1)._type.isa(_t) ? in(1) : null;
+ }
+
+ @Override
+ boolean eq(Node n) {
+ CastNode cast = (CastNode)n; // Contract
+ return _t==cast._t;
+ }
+
+ @Override
+ int hash() { return _t.hashCode(); }
+
+ @Override
+ public Parser.ParseException err() {
+ // Has a condition to test, so OK
+ if( in(0) != null ) return null;
+ // No condition to test, so this must optimize away
+ throw Utils.TODO();
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ConstantNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ConstantNode.java
new file mode 100644
index 00000000..d788cff7
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ConstantNode.java
@@ -0,0 +1,70 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFunPtr;
+import java.util.BitSet;
+
+/**
+ * A Constant node represents a constant value. At present, the only constants
+ * that we allow are integer literals; therefore Constants contain an integer
+ * value. As we add other types of constants, we will refactor how we represent
+ * Constants.
+ * <p>
+ * Constants have no semantic inputs. However, we set Start as an input to
+ * Constants to enable a forward graph walk. This edge carries no semantic
+ * meaning, and it is present <em>solely</em> to allow visitation.
+ * <p>
+ * The Constant's value is the value stored in it.
+ */
+
+public class ConstantNode extends Node {
+ public final Type _con;
+ public ConstantNode( Type type ) {
+ super(new Node[]{CodeGen.CODE._start});
+ _con = _type = type;
+ }
+ public ConstantNode( ConstantNode con ) { super(con); _con = con._type; }
+
+ public static Node make( Type type ) {
+ if( type==Type. CONTROL ) return new CtrlNode();
+ if( type==Type.XCONTROL ) return new XCtrlNode();
+ return new ConstantNode(type);
+ }
+
+ @Override public String label() { return "#"+_con; }
+ @Override public String glabel() { return _con.gprint(new SB().p("#")).toString(); }
+
+ @Override
+ public String uniqueName() { return "Con_" + _nid; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ if( _con instanceof TypeFunPtr tfp ) {
+ FunNode fun = CodeGen.CODE.link(tfp);
+ if( fun._name != null )
+ return sb.append("{ ").append(fun._name).append("}");
+ }
+ return sb.append(_con.print(new SB()));
+ }
+
+ @Override public boolean isMultiTail() { return true; }
+ @Override public boolean isConst() { return true; }
+
+ @Override
+ public Type compute() { return _con; }
+
+ @Override
+ public Node idealize() { return null; }
+
+ @Override
+ boolean eq(Node n) {
+ ConstantNode con = (ConstantNode)n; // Contract
+ return _con==con._con;
+ }
+
+ @Override
+ int hash() { return _con.hashCode(); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/CtrlNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/CtrlNode.java
new file mode 100644
index 00000000..0ea060bd
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/CtrlNode.java
@@ -0,0 +1,15 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import java.util.BitSet;
+
+public class CtrlNode extends CFGNode {
+ public CtrlNode() { super(CodeGen.CODE._start); }
+ @Override public String label() { return "Ctrl"; }
+ @Override StringBuilder _print1(StringBuilder sb, BitSet visited) { return sb.append("Cctrl"); }
+ @Override public boolean isConst() { return true; }
+ @Override public Type compute() { return Type.CONTROL; }
+ @Override public Node idealize() { return null; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/DivFNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/DivFNode.java
new file mode 100644
index 00000000..36fd4524
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/DivFNode.java
@@ -0,0 +1,46 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFloat;
+
+import java.util.BitSet;
+
+public class DivFNode extends Node {
+ public DivFNode(Node lhs, Node rhs) { super(null, lhs, rhs); }
+
+ @Override public String label() { return "DivF"; }
+
+ @Override public String glabel() { return "/"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append("/"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ if (in(1)._type instanceof TypeFloat i0 &&
+ in(2)._type instanceof TypeFloat i1) {
+ if (i0.isConstant() && i1.isConstant())
+ return TypeFloat.constant(i0.value()/i1.value());
+ }
+ return in(1)._type.meet(in(2)._type);
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t1 = lhs._type;
+ Type t2 = rhs._type;
+
+ // Div of 1.
+ if ( t2.isConstant() && t2 instanceof TypeFloat i && i.value()==1 )
+ return lhs;
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new DivFNode(lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/DivNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/DivNode.java
new file mode 100644
index 00000000..0d5ed297
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/DivNode.java
@@ -0,0 +1,46 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+public class DivNode extends Node {
+ public DivNode(Node lhs, Node rhs) { super(null, lhs, rhs); }
+
+ @Override public String label() { return "Div"; }
+
+ @Override public String glabel() { return "//"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append("/"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if( t1 instanceof TypeInteger i1 &&
+ t2 instanceof TypeInteger i2 ) {
+ if (i1.isConstant() && i2.isConstant())
+ return i2.value() == 0
+ ? TypeInteger.ZERO
+ : TypeInteger.constant(i1.value()/i2.value());
+ }
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ // Div of 1.
+ if( in(2)._type == TypeInteger.TRUE )
+ return in(1);
+ return null;
+ }
+
+ @Override Node copy(Node lhs, Node rhs) { return new DivNode(lhs,rhs); }
+ @Override Node copyF() { return new DivFNode(null,null); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/FRefNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/FRefNode.java
new file mode 100644
index 00000000..f0c4045d
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/FRefNode.java
@@ -0,0 +1,35 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.Var;
+import com.seaofnodes.simple.type.Type;
+import java.util.BitSet;
+
+/**
+ * A Forward Reference. Its any final constant, including functions. When
+ * the Def finally appears its plugged into the forward reference, which then
+ * peepholes to the Def.
+ */
+public class FRefNode extends ConstantNode {
+ public static final Type FREF_TYPE = Type.BOTTOM;
+ public final Var _n;
+ public FRefNode( Var n ) { super(FREF_TYPE); _n = n; }
+
+ @Override public String label() { return "FRef"+_n; }
+
+ @Override public String uniqueName() { return "FRef_" + _nid; }
+
+ @Override StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ return sb.append("FRef_").append(_n);
+ }
+
+ @Override public Node idealize() {
+ // When FRef finds its definition, idealize to it
+ return nIns()==1 ? null : in(1);
+ }
+
+ public Parser.ParseException err() { return Parser.error("Undefined name '"+_n._name+"'",_n._loc); }
+
+ @Override boolean eq(Node n) { return this==n; }
+ @Override int hash() { return _n._idx; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/FunNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/FunNode.java
new file mode 100644
index 00000000..506e7758
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/FunNode.java
@@ -0,0 +1,149 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFunPtr;
+import java.util.BitSet;
+import static com.seaofnodes.simple.CodeGen.CODE;
+
+public class FunNode extends RegionNode {
+
+ // When set true, this Call/CallEnd/Fun/Return is being trivially inlined
+ boolean _folding;
+
+ private TypeFunPtr _sig; // Initial signature
+ private ReturnNode _ret; // Return pointer
+
+ public String _name; // Debug name
+
+ public FunNode( Parser.Lexer loc, TypeFunPtr sig, Node... nodes ) { super(loc,nodes); _sig = sig; }
+ public FunNode( FunNode fun ) { super( fun, fun._loc ); _sig = fun.sig(); _name = fun._name; }
+
+ @Override
+ public String label() { return _name == null ? "$fun" : _name; }
+
+ // Find the one CFG user from Fun. It's not always the Return, but always
+ // the Return *is* a CFG user of Fun.
+ @Override public CFGNode uctrl() {
+ for( Node n : _outputs )
+ if( n instanceof CFGNode cfg &&
+ (cfg instanceof RegionNode || cfg.cfg0()==this) )
+ return cfg;
+ return null;
+ }
+
+ public ParmNode rpc() {
+ ParmNode rpc = null;
+ for( Node n : _outputs )
+ if( n instanceof ParmNode parm && parm._idx==0 )
+ { assert rpc==null; rpc=parm; }
+ return rpc;
+ }
+
+ // Cannot create the Return and Fun at the same time; one has to be first.
+ // So setting the return requires a second step.
+ public void setRet(ReturnNode ret) { _ret=ret; }
+ ReturnNode ret() { assert _ret!=null; return _ret; }
+
+ // Signature can improve over time
+ public TypeFunPtr sig() { return _sig; }
+ void setSig( TypeFunPtr sig ) {
+ assert sig.isa(_sig);
+ if( _sig != sig ) {
+ CODE.add(this);
+ _sig = sig;
+ }
+ }
+
+ @Override
+ public Type compute() {
+ // Only dead if no callers after SCCP
+ return Type.CONTROL;
+ }
+
+ @Override
+ public Node idealize() {
+
+ // Some linked path dies
+ Node progress = deadPath();
+ if( progress!=null ) {
+ if( nIns()==3 && in(2) instanceof CallNode call )
+ CODE.add(call.cend()); // If Start and one call, check for inline
+ return progress;
+ }
+
+ // When can we assume no callers? Or no other callers (except main)?
+ // In a partial compilation, we assume Start gets access to any/all
+ // top-level public structures and recursively what they point to.
+ // This in turn is valid arguments to every callable function.
+ //
+ // In a total compilation, we can start from Start and keep things
+ // more contained.
+
+ // If no default/unknown caller, use the normal RegionNode ideal rules
+ // to collapse
+ if( unknownCallers() ) return null;
+
+ // If down to a single input, become that input
+ if( nIns()==2 && !hasPhi() ) {
+ CODE.add( CODE._stop ); // Stop will remove dead path
+ CODE.add( _ret ); // Return will compute to TOP control
+ return in(1); // Collapse if no Phis; 1-input Phis will collapse on their own
+ }
+
+ return null;
+ }
+
+ // Bypass Region idom, always assume depth == 1, one more than Start
+ @Override public int idepth() { return (_idepth=1); }
+ // Bypass Region idom, always assume idom is Start
+ @Override public CFGNode idom(Node dep) { return cfg(1); }
+
+ // Always in-progress until we run out of unknown callers
+ public boolean unknownCallers() { return in(1) instanceof StartNode; }
+
+ @Override public boolean inProgress() { return unknownCallers(); }
+
+ // Add a new function exit point.
+ public void addReturn(Node ctrl, Node mem, Node rez) { _ret.addReturn(ctrl,mem,rez); }
+
+ // Build the function body
+ public BitSet body() {
+
+ // Reverse up (stop to start) CFG only, collect bitmap.
+ BitSet cfgs = new BitSet();
+ cfgs.set(_nid);
+ walkUp(ret(),cfgs );
+
+ // Top down (start to stop) all flavors. CFG limit to bitmap.
+ // If data use bottoms out in wrong CFG, returns false - but tries all outputs.
+ // If any output hits an in-CFG use (e.g. phi), then keep node.
+ BitSet body = new BitSet();
+ walkDown(this, cfgs, body, new BitSet());
+ return body;
+ }
+
+ private static void walkUp(CFGNode n, BitSet cfgs) {
+ if( cfgs.get(n._nid) ) return;
+ cfgs.set(n._nid);
+ if( n instanceof RegionNode r )
+ for( int i=1; i<n.nIns(); i++ )
+ walkUp(n.cfg(i),cfgs);
+ else walkUp(n.cfg0(),cfgs);
+ }
+
+ private static boolean walkDown( Node n, BitSet cfgs, BitSet body, BitSet visit ) {
+ if( visit.get(n._nid) ) return body.get(n._nid);
+ visit.set(n._nid);
+
+ if( n instanceof CFGNode && !cfgs.get(n._nid) )
+ return false;
+ if( n.in(0)!=null && !cfgs.get(n.in(0)._nid) )
+ return false;
+ boolean in = n.in(0)!=null || n instanceof CFGNode;
+ for( Node use : n._outputs )
+ in |= walkDown(use,cfgs,body,visit);
+ if( in ) body.set(n._nid);
+ return in;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/IfNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/IfNode.java
new file mode 100644
index 00000000..9e6d2dff
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/IfNode.java
@@ -0,0 +1,69 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.IterPeeps;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+import java.util.HashSet;
+
+public class IfNode extends CFGNode implements MultiNode {
+
+ public IfNode(Node ctrl, Node pred) {
+ super(ctrl, pred);
+ CodeGen.CODE.add(this); // Because idoms are complex, just add it
+ }
+ public IfNode(IfNode iff) { super(iff); }
+
+ @Override
+ public String label() { return "If"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ sb.append("if( ");
+ return in(1)._print0(sb, visited).append(" )");
+ }
+
+ @Override public boolean isMultiHead() { return true; }
+
+ public Node ctrl() { return in(0); }
+ public Node pred() { return in(1); }
+
+ // No one unique control follows
+ @Override public CFGNode uctrl() { return null; }
+
+ @Override
+ public Type compute() {
+ // If the If node is not reachable then neither is any following Proj
+ if (ctrl()._type != Type.CONTROL && ctrl()._type != Type.BOTTOM )
+ return TypeTuple.IF_NEITHER;
+ Node pred = pred();
+ Type t = pred._type;
+ // High types mean NEITHER side is reachable.
+ // Wait until the type falls to decide which way to go.
+ if( t.isHigh() )
+ return TypeTuple.IF_NEITHER;
+ // If constant is 0 then false branch is reachable
+ // Else true branch is reachable
+ if( t.isConstant() )
+ return (t==Type.NIL || t==TypeInteger.ZERO || (t instanceof TypeFunPtr tfp && tfp._fidxs==0) ) ? TypeTuple.IF_FALSE : TypeTuple.IF_TRUE;
+ // If adding a zero makes a difference, the predicate must not have a zero/null
+ if( !t.makeZero().isa(t) )
+ return TypeTuple.IF_TRUE;
+
+ return TypeTuple.IF_BOTH;
+ }
+
+ @Override
+ public Node idealize() {
+ // Hunt up the immediate dominator tree. If we find an identical if
+ // test on either the true or false branch, that side wins.
+ if( !pred()._type.isHighOrConst() )
+ for( CFGNode dom = idom(), prior=this; dom!=null; prior = dom, dom = dom.idom() )
+ if( dom.addDep(this) instanceof IfNode iff && iff.pred().addDep(this)==pred() && prior instanceof CProjNode prj ) {
+ setDef(1,con( prj._idx==0 ? 1 : 0 ));
+ return this;
+ }
+ return null;
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/LoadNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/LoadNode.java
new file mode 100644
index 00000000..6c74042b
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/LoadNode.java
@@ -0,0 +1,210 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+
+/**
+ * Load represents extracting a value from inside a memory object,
+ * in chapter 10 this means Struct fields.
+ */
+public class LoadNode extends MemOpNode {
+
+ /**
+ * Load a value from a ptr.field.
+ *
+ * @param name The field we are loading
+ * @param mem The memory alias node - this is updated after a Store
+ * @param ptr The ptr to the struct base from where we load a field
+ * @param off The offset inside the struct base
+ */
+ public LoadNode(Parser.Lexer loc, String name, int alias, Type glb, Node mem, Node ptr, Node off) {
+ super(loc, name, alias, glb, mem, ptr, off);
+ }
+
+ // GraphVis DOT code (must be valid Java identifiers) and debugger labels
+ @Override public String label() { return "ld_"+mlabel(); }
+ // GraphVis node-internal labels
+ @Override public String glabel() { return "." +_name; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) { return sb.append(".").append(_name); }
+
+ @Override
+ public Type compute() {
+ if( mem()._type instanceof TypeMem mem ) {
+ // Update declared forward ref to the actual
+ if( _declaredType.isFRef() && mem._t instanceof TypeMemPtr tmp && !tmp.isFRef() )
+ _declaredType = tmp;
+ // No lifting if ptr might null-check
+ if( err()==null )
+ return _declaredType.join(mem._t);
+ }
+ return _declaredType;
+ }
+
+ @Override
+ public Node idealize() {
+ Node ptr = ptr();
+ Node mem = mem();
+
+ // Simple Load-after-Store on same address.
+ if( mem instanceof StoreNode st &&
+ ptr == st.ptr() && off() == st.off() ) { // Must check same object
+ assert _name.equals(st._name); // Equiv class aliasing is perfect
+ return extend(st.val());
+ }
+
+ // Simple Load-after-New on same address.
+ if( mem instanceof ProjNode p && p.in(0) instanceof NewNode nnn &&
+ ptr == nnn.proj(1) ) // Must check same object
+ return zero(nnn); // Load zero from new
+
+ // Uplift control to a prior dominating load.
+ for( Node memuse : mem._outputs )
+ // Find a prior load, has same mem,ptr,off but higher ctrl
+ if( memuse != this && memuse instanceof LoadNode ld && ptr==ld.ptr() && off()==ld.off() &&
+ cfg0()!=null && cfg0()._idom(ld.cfg0(),this) == ld.cfg0() ) // Higher control means load is legal earlier
+ return ld;
+
+ // Load-after-Store on same address, but bypassing provably unrelated
+ // stores. This is a more complex superset of the above two peeps.
+ // "Provably unrelated" is really weak.
+ if( ptr instanceof ReadOnlyNode ro )
+ ptr = ro.in(1);
+ outer:
+ while( true ) {
+ switch( mem ) {
+ case StoreNode st:
+ if( ptr == st.ptr().addDep(this) && off() == st.off() )
+ return extend(castRO(st.val())); // Proved equal
+ // Can we prove unequal? Offsets do not overlap?
+ if( !off()._type.join(st.off()._type).isHigh() && // Offsets overlap
+ !neverAlias(ptr,st.ptr()) ) // And might alias
+ break outer; // Cannot tell, stop trying
+ // Pointers cannot overlap
+ mem = st.mem(); // Proved never equal
+ break;
+ case PhiNode phi:
+ // Assume related
+ phi.addDep(this);
+ break outer;
+ case ConstantNode top: break outer; // Assume shortly dead
+ case ProjNode mproj: // Memory projection
+ switch( mproj.in(0) ) {
+ case NewNode nnn1:
+ if( ptr instanceof ProjNode pproj && pproj.in(0) == mproj.in(0) )
+ return zero(nnn1);
+ if( !(ptr instanceof ProjNode pproj && pproj.in(0) instanceof NewNode) )
+ break outer; // Cannot tell, ptr not related to New
+ mem = nnn1.in(nnn1.findAlias(_alias));// Bypass unrelated New
+ break;
+ case StartNode start: break outer;
+ case CallEndNode cend: break outer; // TODO: Bypass no-alias call
+ default: throw Utils.TODO();
+ }
+ break;
+ case MemMergeNode merge: mem = merge.alias(_alias); break;
+
+ default:
+ throw Utils.TODO();
+ }
+ }
+
+ // Push a Load up through a Phi, as long as it collapses on at least
+ // one arm. If at a Loop, the backedge MUST collapse - else we risk
+ // spinning the same transform around the loop indefinitely.
+ // BEFORE (2 Sts, 1 Ld): AFTER (1 St, 0 Ld):
+ // if( pred ) ptr.x = e0; val = pred ? e0
+ // else ptr.x = e1; : e1;
+ // val = ptr.x; ptr.x = val;
+ if( mem() instanceof PhiNode memphi && memphi.region()._type == Type.CONTROL && memphi.nIns()== 3 &&
+ // Offset can be hoisted
+ off() instanceof ConstantNode &&
+ // Pointer can be hoisted
+ hoistPtr(ptr,memphi) ) {
+
+ // Profit on RHS/Loop backedge
+ if( profit(memphi,2) ||
+ // Else must not be a loop to count profit on LHS.
+ (!(memphi.region() instanceof LoopNode) && profit(memphi,1)) ) {
+ Node ld1 = ld(1);
+ Node ld2 = ld(2);
+ return new PhiNode(_name,_declaredType,memphi.region(),ld1,ld2);
+ }
+ }
+
+ return null;
+ }
+
+ // Load a flavored zero from a New
+ private Node zero(NewNode nnn) {
+ TypeStruct ts = nnn._ptr._obj;
+ Type zero = ts._fields[ts.findAlias(_alias)]._type.makeZero();
+ return castRO(new ConstantNode(zero).peephole());
+ }
+
+ private Node ld( int idx ) {
+ Node mem = mem(), ptr = ptr();
+ return new LoadNode(_loc,_name,_alias,_declaredType,mem.in(idx),ptr instanceof PhiNode && ptr.in(0)==mem.in(0) ? ptr.in(idx) : ptr, off()).peephole();
+ }
+
+ private static boolean neverAlias( Node ptr1, Node ptr2 ) {
+ return ptr1.in(0) != ptr2.in(0) &&
+ // Unrelated allocations
+ ptr1 instanceof ProjNode && ptr1.in(0) instanceof NewNode &&
+ ptr2 instanceof ProjNode && ptr2.in(0) instanceof NewNode;
+ }
+
+ private static boolean hoistPtr(Node ptr, PhiNode memphi ) {
+ // Can I hoist ptr above the Region?
+ if( !(memphi.region() instanceof RegionNode r) )
+ return false; // Dead or dying Region/Phi
+ // If ptr from same Region, then yes, just use hoisted split pointers
+ if( ptr instanceof PhiNode pphi && pphi.region() == r )
+ return true;
+
+ // No, so can we lift this ptr?
+ CFGNode cptr = ptr.cfg0();
+ if( cptr != null )
+ // Pointer is controlled high
+ // TODO: Really needs to be the LCA of all inputs is high
+ return cptr.idepth() <= r.idepth();
+
+ // Dunno without a longer walk
+ return false;
+ }
+
+ // Profitable if we find a matching Store on this Phi arm.
+ private boolean profit(PhiNode phi, int idx) {
+ Node px = phi.in(idx);
+ if( px==null ) return false;
+ if( px._type instanceof TypeMem mem && mem._t.isHighOrConst() ) return true;
+ if( px instanceof StoreNode st1 && ptr()==st1.ptr() && off()==st1.off() ) return true;
+ px.addDep(this);
+ return false;
+ }
+
+ // Read-Only is a deep property, and cannot be cast-away
+ private Node castRO(Node rez) {
+ if( ptr()._type.isFinal() && !rez._type.isFinal() )
+ return new ReadOnlyNode(rez).peephole();
+ return rez;
+ }
+
+ // When a load bypasses a store, the store might truncate bits - and the
+ // load will need to zero/sign-extend.
+ private Node extend(Node val) {
+ if( !(_declaredType instanceof TypeInteger ti) ) return val;
+ if( ti._min==0 ) // Unsigned
+ return new AndNode(null,val,con(ti._max));
+ // Signed extension
+ int shift = Long.numberOfLeadingZeros(ti._max)-1;
+ Node shf = con(shift);
+ if( shf._type==TypeInteger.ZERO )
+ return val;
+ //return peep(new SarNode(null,peep(new ShlNode(null,val,shf.keep())),shf.unkeep()));
+ throw Utils.TODO();
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/LogicalNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/LogicalNode.java
new file mode 100644
index 00000000..ccc1f6b5
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/LogicalNode.java
@@ -0,0 +1,29 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+public abstract class LogicalNode extends Node {
+ // Source location for late reported errors
+ Parser.Lexer _loc;
+
+ public LogicalNode(Parser.Lexer loc, Node lhs, Node rhs) { super(null, lhs, rhs); _loc = loc; }
+ abstract String op();
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append(op()), visited);
+ return sb.append(")");
+ }
+
+
+ @Override public Parser.ParseException err() {
+ if( in(1)._type.isHigh() || in(2)._type.isHigh() ) return null;
+ if( !(in(1)._type instanceof TypeInteger) ) return Parser.error("Cannot '"+op()+"' " + in(1)._type.glb(),_loc);
+ if( !(in(2)._type instanceof TypeInteger) ) return Parser.error("Cannot '"+op()+"' " + in(2)._type.glb(), _loc);
+ return null;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/LoopNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/LoopNode.java
new file mode 100644
index 00000000..d2b0e36c
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/LoopNode.java
@@ -0,0 +1,86 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeMem;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+import java.util.HashSet;
+
+public class LoopNode extends RegionNode {
+ public LoopNode( Parser.Lexer loc, Node entry ) { super(loc,null,entry,null); }
+ public LoopNode( LoopNode loop ) { super(loop); }
+
+ public CFGNode entry() { return cfg(1); }
+ public CFGNode back () { return cfg(2); }
+
+ @Override
+ public String label() { return "Loop"; }
+
+ @Override
+ public Type compute() {
+ if( inProgress() ) return Type.CONTROL;
+ return entry()._type;
+ }
+
+ // Bypass Region idom, same as the default idom() using use in(1) instead of in(0)
+ @Override public int idepth() { return _idepth==0 ? (_idepth=idom().idepth()+1) : _idepth; }
+ // Bypass Region idom, same as the default idom() using use in(1) instead of in(0)
+ @Override public CFGNode idom(Node dep) { return entry(); }
+
+ // If this is an unreachable loop, it may not have an exit. If it does not
+ // (i.e., infinite loop), force an exit to make it reachable.
+ public StopNode forceExit( FunNode fun, StopNode stop ) {
+ // Walk the backedge, then immediate dominator tree util we hit this
+ // Loop again. If we ever hit a CProj from an If (as opposed to
+ // directly on the If) we found our exit.
+ CFGNode x = back();
+ while( x != this ) {
+ if( x instanceof CProjNode exit && exit.in(0) instanceof IfNode iff ) {
+ CFGNode other = iff.cproj(1-exit._idx);
+ if( other!=null && other.loopDepth() < loopDepth() )
+ return stop; // Found an exit, not an infinite loop
+ }
+ x = x.idom();
+ }
+ // Found a no-exit loop. Insert an exit
+ NeverNode iff = new NeverNode(back());
+ for( Node use : _outputs )
+ if( use instanceof PhiNode )
+ iff.addDef(use);
+ CProjNode t = new CProjNode(iff,0,"True" ).init();
+ CProjNode f = new CProjNode(iff,1,"False").init();
+ setDef(2,f);
+
+ // Now fold control into the exit. Might have 1 valid exit, or an
+ // XCtrl or a bunch of prior NeverNode exits.
+ Node top = new ConstantNode(Type.TOP).peephole();
+ ReturnNode ret = fun.ret();
+ Node ctrl = ret.ctrl(), mem = ret.mem(), expr = ret.expr();
+ if( ctrl._type != Type.XCONTROL ) {
+ // Perfect aligned exit?
+ if( !(ctrl instanceof RegionNode r &&
+ mem instanceof PhiNode pmem && pmem.region()==r &&
+ expr instanceof PhiNode prez && prez.region()==r ) ) {
+ // Nope, insert an aligned exit layer
+ ctrl = new RegionNode(_loc,null,ctrl).init();
+ mem = new PhiNode((RegionNode)ctrl,mem ).init();
+ expr = new PhiNode((RegionNode)ctrl,expr).init();
+ }
+ // Append new Never exit
+ ctrl.addDef(t );
+ mem .addDef(top);
+ expr.addDef(top);
+ } else {
+ ctrl = t;
+ mem = top;
+ expr = top;
+ }
+ ret.setDef(0,ctrl);
+ ret.setDef(1,mem );
+ ret.setDef(2,expr);
+
+ return stop;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MachConcreteNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MachConcreteNode.java
new file mode 100644
index 00000000..0c49fc64
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MachConcreteNode.java
@@ -0,0 +1,27 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.Utils;
+import java.io.ByteArrayOutputStream;
+import java.util.BitSet;
+
+// Generic machine-specific class, has a few Node implementations that have to
+// exist (abstract) but are not useful past the optimizer.
+public abstract class MachConcreteNode extends Node implements MachNode{
+
+ public MachConcreteNode(Node node) { super(node); }
+ public MachConcreteNode(Node[]nodes) { super(nodes); }
+
+ @Override public String label() { return op(); }
+ @Override public Type compute () { throw Utils.TODO(); }
+ @Override public Node idealize() { throw Utils.TODO(); }
+
+ @Override public StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ sb.append("(").append(op()).append(",");
+ for( int i=1; i<nIns(); i++ )
+ (in(i)==null ? sb.append(" ---") : in(i)._print0(sb, visited)).append(",");
+ sb.setLength(sb.length()-1);
+ return sb.append(")");
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MachNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MachNode.java
new file mode 100644
index 00000000..9f2fee85
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MachNode.java
@@ -0,0 +1,49 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import java.io.ByteArrayOutputStream;
+
+public interface MachNode {
+
+ // Easy access to the abstract Machine
+ default Machine machine() { return CodeGen.CODE._mach; }
+
+ // Run a post-instruction-selection action
+ default void postSelect() { }
+
+ // Register mask allowed on input i. 0 for no register.
+ abstract public RegMask regmap(int i);
+ // Register mask allowed as a result. 0 for no register.
+ abstract public RegMask outregmap();
+ // Multi-reg-defining machine op; idx comes from Proj.
+ // Sometimes these Projs have no uses, and just exist to kill a register.
+ default RegMask outregmap(int idx) { throw Utils.TODO(); }
+
+ // If this op updates the same register as input 'idx', e.g. many X86 "R1 +=
+ // R2" style ops. This forces the output live range to equal the input live
+ // range, so they both get the same register.
+
+ // This can hold true for projections, if the instruction updates many
+ // registers that it also takes in. Note that ops also use the same
+ // registers for both inputs and outputs but these are pinned and without any
+ // choices (e.g. always RCX for both an input and output) and are better
+ // served with just declaring as a fixed register.
+
+ // Returns either 0 for not-two-adr or the updated input; for projections
+ // this is their Multi's updated input.
+ default int twoAddress( ) { return 0; }
+
+ // Instructions cheaper to recreate than to spill, such as loading small constants
+ default boolean isClone() { return false; }
+ // Encoding is appended into the byte array; size is returned
+ abstract public int encoding(ByteArrayOutputStream bytes);
+
+ // Human-readable form appended to the SB. Things like the encoding,
+ // indentation, leading address or block labels not printed here.
+ // Just something like "R17=[R18+12] // Load array base".
+ // General form: "dst=src+src".
+ default void asm(CodeGen code, SB sb) { throw Utils.TODO(); }
+
+ // Human readable opcode; e.g. "ld4" or "call".
+ default String op() { throw Utils.TODO(); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MemMergeNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MemMergeNode.java
new file mode 100644
index 00000000..5363bb6f
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MemMergeNode.java
@@ -0,0 +1,154 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.type.*;
+import java.util.*;
+
+/**
+ * Memory Merge - a merge of many aliases into a "fat memory". All aliases
+ * are here, but most will be lazy - take the default fat memory.
+ */
+public class MemMergeNode extends Node {
+
+ /*
+ * In-Progress means this is being used by the Parser to track memory
+ * aliases. No optimizations are allowed. When no longer "in progress"
+ * normal peeps work.
+ */
+ public final boolean _inProgress;
+
+ public MemMergeNode( boolean inProgress) { _type = TypeMem.BOT; _inProgress = inProgress; }
+ public MemMergeNode(MemMergeNode mem) { super(mem); _inProgress = false; }
+
+
+ // If being used by a Scope, this is "in progress" from the Parser.
+ // Otherwise, it's a memory merge
+ boolean inProgress() { return _inProgress; }
+
+ @Override public String label() { return "ALLMEM"; }
+ @Override public boolean isMem() { return true; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ sb.append(_inProgress ? "Merge[" : "MEM[ ");
+ for( int j=2; j<nIns(); j++ ) {
+ sb.append(j);
+ sb.append(":");
+ Node n = in(j);
+ while( n instanceof ScopeNode loop ) {
+ sb.append("Lazy_");
+ n = loop.mem(j);
+ }
+ if( n==null ) sb.append("___ ");
+ else n._print0(sb, visited).append(" ");
+ }
+ sb.setLength(sb.length()-1);
+ return sb.append("]");
+ }
+
+ // Make a memory merge: no longer a Scope really, tracking memory state but
+ // not related to the parser in any way.
+ public Node merge() {
+ // Force default memory to not be lazy
+ MemMergeNode merge = new MemMergeNode(false);
+ for( Node n : _inputs )
+ merge.addDef(n);
+ merge._mem(1,null);
+ return merge.peephole();
+ }
+
+
+ @Override public Type compute() { return TypeMem.BOT; }
+
+ @Override public Node idealize() {
+ if( inProgress() ) return null;
+
+ // If not merging any memory (all memory is just the default)
+ if( nIns()==2 )
+ return in(1); // Become default memory
+
+ return null;
+ }
+
+ public Node in( Var v ) { return in(v._idx); }
+
+ public Node alias( int alias ) {
+ return in(alias<nIns() && in(alias)!=null ? alias : 1);
+ }
+
+ Node alias( int alias, Node st ) {
+ while( alias >= nIns() ) addDef(null);
+ return setDef(alias,st);
+ }
+
+ // Read or update from memory.
+ // A shared implementation allows us to create lazy phis both during
+ // lookups and updates; the lazy phi creation is part of chapter 8.
+ Node _mem( int alias, Node st ) {
+ // Memory projections are made lazily; if one does not exist
+ // then it must be START.proj(1)
+ Node old = alias(alias);
+ if( old instanceof ScopeNode loop ) {
+ MemMergeNode loopmem = loop.mem();
+ Node memdef = loopmem.alias(alias);
+ // Lazy phi!
+ old = memdef instanceof PhiNode phi && loop.ctrl()==phi.region()
+ // Loop already has a real Phi, use it
+ ? memdef
+ // Set real Phi in the loop head
+ // The phi takes its one input (no backedge yet) from a recursive
+ // lookup, which might have insert a Phi in every loop nest.
+ : loopmem.alias(alias, new PhiNode(Parser.memName(alias), TypeMem.BOT,loop.ctrl(),loopmem._mem(alias,null),null).peephole() );
+ alias(alias,old);
+ }
+ // Memory projections are made lazily; expand as needed
+ return st==null ? old : alias(alias,st); // Not lazy, so this is the answer
+ }
+
+
+ void _merge( MemMergeNode that, RegionNode r) {
+ int len = Math.max(nIns(),that.nIns());
+ for( int i = 2; i < len; i++)
+ if( alias(i) != that.alias(i) ) { // No need for redundant Phis
+ // If we are in lazy phi mode we need to a lookup
+ // by alias as it will trigger a phi creation
+ Node lhs = this._mem(i,null);
+ Node rhs = that._mem(i,null);
+ alias(i, new PhiNode(Parser.memName(i), lhs._type.glb().meet(rhs._type.glb()), r, lhs, rhs).peephole());
+ }
+ }
+
+ // Fill in the backedge of any inserted Phis
+ void _endLoopMem( ScopeNode scope, MemMergeNode back, MemMergeNode exit ) {
+ Node exit_def = exit.alias(1);
+ for( int i=1; i<nIns(); i++ ) {
+ if( in(i) instanceof PhiNode phi && phi.region()==scope.ctrl() ) {
+ assert phi.in(2)==null;
+ phi.setDef(2,back.in(i)==scope ? phi : back.in(i)); // Fill backedge
+ }
+ if( exit_def == scope ) // Replace a lazy-phi on the exit path also
+ exit.alias(i,in(i));
+ }
+ }
+
+ // Now one-time do a useless-phi removal
+ void _useless( ) {
+ for( int i=2; i<nIns(); i++ ) {
+ if( in(i) instanceof PhiNode phi ) {
+ // Do an eager useless-phi removal
+ Node in = phi.peephole();
+ CodeGen.CODE.addAll(phi._outputs);
+ phi.moveDepsToWorklist();
+ if( in != phi ) {
+ if( !phi.iskeep() ) // Keeping phi around for parser elsewhere
+ phi.subsume(in);
+ setDef(i,in); // Set the update back into Scope
+ }
+ }
+ }
+ }
+
+ @Override boolean eq( Node n ) {
+ return this==n || !_inProgress;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MemOpNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MemOpNode.java
new file mode 100644
index 00000000..d9ab6b89
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MemOpNode.java
@@ -0,0 +1,74 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeMemPtr;
+import java.lang.StringBuilder;
+import java.util.BitSet;
+
+/**
+ * Convenience common base for Load and Store.
+ */
+public abstract class MemOpNode extends Node {
+
+ public final String _name;
+ public final int _alias;
+ // Declared type; not final because it might be a forward-reference
+ // which will be lazily improved when the reference is declared.
+ public Type _declaredType;
+ // Source location for late reported errors
+ public final Parser.Lexer _loc;
+
+ public MemOpNode(Parser.Lexer loc, String name, int alias, Type glb, Node mem, Node ptr, Node off) {
+ super(null, mem, ptr, off);
+ _name = name;
+ _alias = alias;
+ _declaredType = glb;
+ _loc = loc;
+ }
+ public MemOpNode(Parser.Lexer loc, String name, int alias, Type glb, Node mem, Node ptr, Node off, Node value) {
+ this(loc,name, alias, glb, mem, ptr, off);
+ addDef(value);
+ }
+ public MemOpNode( Node mach, MemOpNode mop ) {
+ super(mach);
+ _name = mop._name;
+ _alias = mop._alias;
+ _declaredType = mop._declaredType;
+ _loc = mop._loc;
+ }
+
+ //
+ static String mlabel(String name) { return name.equals("[]") ? "ary" : (name.equals("#") ? "len" : name); }
+ String mlabel() { return mlabel(_name); }
+
+ public Node mem() { return in(1); }
+ public Node ptr() { return in(2); }
+ public Node off() { return in(3); }
+
+ @Override StringBuilder _print1( StringBuilder sb, BitSet visited ) { return _printMach(sb,visited); }
+ public StringBuilder _printMach( StringBuilder sb, BitSet visited ) { throw Utils.TODO(); }
+
+
+ @Override
+ boolean eq(Node n) {
+ MemOpNode mem = (MemOpNode)n; // Invariant
+ return _alias==mem._alias; // When comparing types error to use "equals"; always use "=="
+ }
+
+ @Override
+ int hash() { return _alias; }
+
+ @Override
+ public Parser.ParseException err() {
+ Type ptr = ptr()._type;
+ // Already an error, but better error messages come from elsewhere
+ if( ptr == Type.BOTTOM ) return null;
+ if( ptr.isHigh() ) return null; // Assume it will fall to not-null
+ // Better be a not-nil TMP
+ if( ptr instanceof TypeMemPtr tmp && tmp.notNull() )
+ return null;
+ return Parser.error( "Might be null accessing '" + _name + "'",_loc);
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MinusFNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MinusFNode.java
new file mode 100644
index 00000000..2b749ba3
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MinusFNode.java
@@ -0,0 +1,36 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFloat;
+
+import java.util.BitSet;
+
+public class MinusFNode extends Node {
+ public MinusFNode(Node in) { super(null, in); }
+
+ @Override public String label() { return "MinusF"; }
+
+ @Override public String glabel() { return "-"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("(-"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ if (in(1)._type instanceof TypeFloat i0)
+ return i0.isConstant() ? TypeFloat.constant(-i0.value()) : i0;
+ return TypeFloat.F64;
+ }
+
+ @Override
+ public Node idealize() {
+ // -(-x) is x
+ if( in(1) instanceof MinusFNode minus )
+ return minus.in(1);
+
+ return null;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MinusNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MinusNode.java
new file mode 100644
index 00000000..dd2cbd26
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MinusNode.java
@@ -0,0 +1,40 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import com.seaofnodes.simple.Utils;
+
+import java.util.BitSet;
+
+public class MinusNode extends Node {
+ public MinusNode(Node in) { super(null, in); }
+
+ @Override public String label() { return "Minus"; }
+
+ @Override public String glabel() { return "-"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("(-"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ if( in(1)._type.isHigh() ) return TypeInteger.TOP;
+ if( in(1)._type instanceof TypeInteger i0 &&
+ !(i0==TypeInteger.BOT || i0._min == Long.MIN_VALUE || i0._max == Long.MIN_VALUE) )
+ return TypeInteger.make(-i0._max,-i0._min);
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ // -(-x) is x
+ if( in(1) instanceof MinusNode minus )
+ return minus.in(1);
+
+ return null;
+ }
+ @Override Node copyF() { return new MinusFNode(null); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MulFNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MulFNode.java
new file mode 100644
index 00000000..2d44a9fb
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MulFNode.java
@@ -0,0 +1,51 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFloat;
+
+import java.util.BitSet;
+
+public class MulFNode extends Node {
+ public MulFNode(Node lhs, Node rhs) { super(null, lhs, rhs); }
+
+ @Override public String label() { return "MulF"; }
+
+ @Override public String glabel() { return "*"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append("*"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ if (in(1)._type instanceof TypeFloat i0 &&
+ in(2)._type instanceof TypeFloat i1) {
+ if (i0.isConstant() && i1.isConstant())
+ return TypeFloat.constant(i0.value()*i1.value());
+ }
+ return in(1)._type.meet(in(2)._type);
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t1 = lhs._type;
+ Type t2 = rhs._type;
+
+ // Mul of 1. We do not check for (1*x) because this will already
+ // canonicalize to (x*1)
+ if ( t2.isConstant() && t2 instanceof TypeFloat i && i.value()==1 )
+ return lhs;
+
+ // Move constants to RHS: con*arg becomes arg*con
+ if ( t1.isConstant() && !t2.isConstant() )
+ return swap12();
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new MulFNode(lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MulNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MulNode.java
new file mode 100644
index 00000000..4fdf987d
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MulNode.java
@@ -0,0 +1,81 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+public class MulNode extends Node {
+ public MulNode(Node lhs, Node rhs) { super(null, lhs, rhs); }
+
+ @Override public String label() { return "Mul"; }
+
+ @Override public String glabel() { return "*"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append("*"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if( t1 instanceof TypeInteger i1 &&
+ t2 instanceof TypeInteger i2 ) {
+ if( i1==TypeInteger.ZERO || i2==TypeInteger.ZERO)
+ return TypeInteger.ZERO;
+ if (i1.isConstant() && i2.isConstant())
+ return TypeInteger.constant(i1.value()*i2.value());
+ }
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t1 = lhs._type;
+ Type t2 = rhs._type;
+
+ // Move constants to RHS: con*arg becomes arg*con
+ if ( t1.isConstant() && !t2.isConstant() )
+ return swap12();
+
+ // Multiply by constant
+ if ( t2.isConstant() && t2 instanceof TypeInteger i ) {
+ // Mul of 1. We do not check for (1*x) because this will already
+ // canonicalize to (x*1)
+ long c = i.value();
+ if( c==1 ) return lhs;
+ if( c==0 ) return Parser.ZERO;
+ // Mul by a power of 2, +/-1. Bit patterns more complex than this
+ // are unlikely to win on an X86 vs the normal "imul", and so
+ // become machine-specific.
+ if( (c & (c-1)) == 0 )
+ return new ShlNode(null,lhs,con(Long.numberOfTrailingZeros(c)));
+ // 2**n + 1, e.g. 9
+ long d = c-1;
+ if( (d & (d-1)) == 0 )
+ return new AddNode(new ShlNode(null,lhs,con(Long.numberOfTrailingZeros(d))).peephole(),lhs);
+ // 2**n - 1, e.g. 31
+ long e = c+1;
+ if( (e & (e-1)) == 0 )
+ return new SubNode(new ShlNode(null,lhs,con(Long.numberOfTrailingZeros(e))).peephole(),lhs);
+
+ }
+
+ // Do we have ((x * (phi cons)) * con) ?
+ // Do we have ((x * (phi cons)) * (phi cons)) ?
+ // Push constant up through the phi: x * (phi con0*con0 con1*con1...)
+ Node phicon = AddNode.phiCon(this,true);
+ if( phicon!=null ) return phicon;
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new MulNode(lhs,rhs); }
+ @Override Node copyF() { return new MulFNode(null,null); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/MultiNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/MultiNode.java
new file mode 100644
index 00000000..17d00881
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/MultiNode.java
@@ -0,0 +1,29 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Ary;
+
+
+public interface MultiNode {
+
+ abstract Ary<Node> outs();
+
+ // Find a projection by index
+ default ProjNode proj( int idx ) {
+ for( Node out : outs() )
+ if( out instanceof ProjNode prj && prj._idx==idx )
+ return prj;
+ return null;
+ }
+
+ // Find a projection by index
+ default CProjNode cproj( int idx ) {
+ for( Node out : outs() )
+ if( out instanceof CProjNode prj && prj._idx==idx )
+ return prj;
+ return null;
+ }
+
+ // Return not-null if this projection index is a ideal copy.
+ // Called by ProjNode ideal and used to collapse Multis.
+ default Node pcopy(int idx) { return null; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/NeverNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/NeverNode.java
new file mode 100644
index 00000000..e77ed653
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/NeverNode.java
@@ -0,0 +1,21 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.TypeInteger;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeTuple;
+
+import java.util.BitSet;
+
+// "Never true" for infinite loop exits
+public class NeverNode extends IfNode {
+ public NeverNode(Node ctrl) { super(ctrl,Parser.ZERO); }
+
+ @Override public String label() { return "Never"; }
+
+ @Override StringBuilder _print1(StringBuilder sb, BitSet visited) { return sb.append("Never"); }
+
+ @Override public Type compute() { return TypeTuple.IF_BOTH; }
+
+ @Override public Node idealize() { return null; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/NewNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/NewNode.java
new file mode 100644
index 00000000..80545d66
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/NewNode.java
@@ -0,0 +1,83 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.*;
+import com.seaofnodes.simple.Utils;
+import java.util.BitSet;
+
+/**
+ * Allocation! Allocate a chunk of memory, and pre-zero it.
+ * The inputs include control and size, and ALL aliases being set.
+ * The output is large tuple, one for every alias plus the created pointer.
+ * New is expected to be followed by projections for every alias.
+ */
+public class NewNode extends Node implements MultiNode {
+
+ public final TypeMemPtr _ptr;
+ public final int _len;
+
+ public NewNode(TypeMemPtr ptr, Node... nodes) {
+ super(nodes);
+ assert !ptr.nullable();
+ _ptr = ptr;
+ _len = ptr._obj._fields.length;
+ // Control in slot 0
+ assert nodes[0]._type==Type.CONTROL || nodes[0]._type == Type.XCONTROL;
+ // Malloc-length in slot 1
+ assert nodes[1]._type instanceof TypeInteger || nodes[1]._type==Type.NIL;
+ for( int i=0; i<_len; i++ )
+ // Memory slices for all fields.
+ assert nodes[2+i]._type.isa(TypeMem.BOT);
+ }
+
+ public NewNode(NewNode nnn) { super(nnn); _ptr = nnn._ptr; _len = nnn._len; }
+
+ public Node mem (int idx) { return in(idx+2); }
+
+ @Override public String label() { return "new_"+glabel(); }
+ @Override public String glabel() {
+ return _ptr._obj.isAry() ? "ary_"+_ptr._obj._fields[1]._type.str() : _ptr._obj.str();
+ }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ sb.append("new ");
+ return sb.append(_ptr._obj.str());
+ }
+
+ int findAlias(int alias) {
+ int idx = _ptr._obj.findAlias(alias);
+ assert idx!= -1; // Error, caller should be calling
+ return idx+2; // Skip ctrl, size
+ }
+
+ // 0 - ctrl
+ // 1 - byte size
+ // 2-len+2 - aliases, one per field
+ // len+2 - 2*len+2 - initial values, one per field
+ public Node size() { return in(1); }
+
+ @Override
+ public TypeTuple compute() {
+ Field[] fs = _ptr._obj._fields;
+ Type[] ts = new Type[fs.length+2];
+ ts[0] = Type.CONTROL;
+ ts[1] = _ptr;
+ for( int i=0; i<fs.length; i++ ) {
+ Type mt = in(i+2)._type;
+ TypeMem mem = mt==Type.TOP ? TypeMem.TOP : (TypeMem)mt;
+ Type tfld = mem._t.meet(mem._t.makeZero());
+ Type tfld2 = tfld.join(fs[i]._type);
+ ts[i+2] = TypeMem.make(fs[i]._alias,tfld2);
+ }
+ return TypeTuple.make(ts);
+ }
+
+ @Override
+ public Node idealize() { return null; }
+
+ @Override
+ boolean eq(Node n) { return this == n; }
+
+ @Override
+ int hash() { return _ptr.hashCode(); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/Node.java b/chapter20/src/main/java/com/seaofnodes/simple/node/Node.java
new file mode 100644
index 00000000..bbf1ebe9
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/Node.java
@@ -0,0 +1,640 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFloat;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.*;
+import java.util.function.Function;
+import static com.seaofnodes.simple.CodeGen.CODE;
+
+/**
+ * All Nodes in the Sea of Nodes IR inherit from the Node class.
+ * The Node class provides common functionality used by all subtypes.
+ * Subtypes of Node specialize by overriding methods.
+ */
+public abstract class Node {
+
+ /**
+ * Each node has a unique dense Node ID within a compilation context
+ * The ID is useful for debugging, for using as an offset in a bitvector,
+ * as well as for computing equality of nodes (to be implemented later).
+ */
+ public final int _nid;
+
+ /**
+ * Inputs to the node. These are use-def references to Nodes.
+ * <p>
+ * Generally fixed length, ordered, nulls allowed, no unused trailing space.
+ * Ordering is required because e.g. "a/b" is different from "b/a".
+ * The first input (offset 0) is often a {@link CFGNode} node.
+ */
+ public final Ary<Node> _inputs;
+
+ /**
+ * Outputs reference Nodes that are not null and have this Node as an
+ * input. These nodes are users of this node, thus these are def-use
+ * references to Nodes.
+ * <p>
+ * Outputs directly match inputs, making a directed graph that can be
+ * walked in either direction. These outputs are typically used for
+ * efficient optimizations but otherwise have no semantics meaning.
+ */
+ public final Ary<Node> _outputs;
+
+
+ /**
+ * Current computed type for this Node. This value changes as the graph
+ * changes and more knowledge is gained about the program.
+ */
+ public Type _type;
+
+
+ Node(Node... inputs) {
+ _nid = CODE.getUID(); // allocate unique dense ID
+ _inputs = new Ary<>(Node.class);
+ Collections.addAll(_inputs,inputs);
+ _outputs = new Ary<>(Node.class);
+ for( Node n : _inputs )
+ if( n != null )
+ n.addUse( this );
+ }
+
+ // Make a Node using the existing arrays of nodes.
+ // Used by any pass rewriting all Node classes but not the edges.
+ Node( Node n ) {
+ assert CodeGen.CODE._phase == CodeGen.Phase.InstructionSelection;
+ _nid = CODE.getUID(); // allocate unique dense ID
+ _inputs = new Ary<>(n._inputs.asAry());
+ _outputs = new Ary<>(Node.class);
+ _type = n._type;
+ _deps = null;
+ _hash = 0;
+ }
+
+ // Easy reading label for debugger, e.g. "Add" or "Region" or "EQ"
+ public abstract String label();
+
+ // Unique label for graph visualization, e.g. "Add12" or "Region30" or "EQ99"
+ public String uniqueName() {
+ // Get rid of $ as graphviz doesn't like it
+ String label = label().replaceAll("\\$", "");
+ return label + _nid;
+ }
+
+ // Graphical label, e.g. "+" or "Region" or "=="
+ public String glabel() { return label(); }
+
+ // Extra fun stuff, for assembly printing. Jump labels, parser locations,
+ // variable types, etc.
+ public String comment() { return null; }
+
+ // ------------------------------------------------------------------------
+
+ // Debugger Printing.
+
+ // {@code toString} is what you get in the debugger. It has to print 1
+ // line (because this is what a debugger typically displays by default) and
+ // has to be robust with broken graph/nodes.
+ @Override
+ public final String toString() { return print(); }
+
+ // This is a *deep* print. We print with a mutually recursive tik-tok
+ // style; the common _print0 calls the per-Node _print1, which calls back
+ // to _print0;
+ public final String print() {
+ return _print0(new StringBuilder(), new BitSet()).toString();
+ }
+
+ // This is the common print: check for repeats, check for DEAD and print
+ // "DEAD" else call the per-Node print1.
+ final StringBuilder _print0(StringBuilder sb, BitSet visited) {
+ if (visited.get(_nid) && !(this instanceof ConstantNode) )
+ return sb.append(label());
+ visited.set(_nid);
+ return isDead()
+ ? sb.append(uniqueName()).append(":DEAD")
+ : _print1(sb, visited);
+ }
+ // Every Node implements this; a partial-line recursive print
+ abstract StringBuilder _print1(StringBuilder sb, BitSet visited);
+
+ public String p(int depth) { return IRPrinter.prettyPrint(this,depth); }
+
+ public boolean isMultiHead() { return false; }
+ public boolean isMultiTail() { return false; }
+ public boolean isConst () { return false; }
+
+ // ------------------------------------------------------------------------
+ // Graph Node & Edge manipulation
+
+ /**
+ * Gets the ith input node
+ * @param i Offset of the input node
+ * @return Input node or null
+ */
+ public Node in(int i) { return _inputs.get(i); }
+ public Node out(int i) { return _outputs.get(i); }
+ public final Ary<Node> outs() { return _outputs; }
+
+ public int nIns() { return _inputs.size(); }
+
+ public int nOuts() { return _outputs.size(); }
+
+ public boolean isUnused() { return nOuts() == 0; }
+
+ public CFGNode cfg0() { return (CFGNode)in(0); }
+
+ /**
+ * Change a <em>def</em> into a Node. Keeps the edges correct, by removing
+ * the corresponding <em>use->def</em> edge. This may make the original
+ * <em>def</em> go dead. This function is co-recursive with {@link #kill}.
+ * <p>
+
+ * This method is the normal path for altering a Node, because it does the
+ * proper default edge maintenance. It also <em>immediately</em> kills
+ * Nodes that lose their last use; at times care must be taken to avoid
+ * killing Nodes that are being used without having an output Node. This
+ * definitely happens in the middle of recursive {@link #peephole} calls.
+ *
+ * @param idx which def to set
+ * @param new_def the new definition
+ * @return new_def for flow coding
+ */
+ public <N extends Node> N setDef(int idx, N new_def ) {
+ unlock();
+ Node old_def = in(idx);
+ if( old_def == new_def ) return new_def; // No change
+ // If new def is not null, add the corresponding def->use edge
+ // This needs to happen before removing the old node's def->use edge as
+ // the new_def might get killed if the old node kills it recursively.
+ if( new_def != null )
+ new_def.addUse(this);
+ // Set the new_def over the old (killed) edge
+ _inputs.set(idx,new_def);
+ if( old_def != null ) { // If the old def exists, remove a def->use edge
+ if( old_def.delUse(this) ) // If we removed the last use, the old def is now dead
+ old_def.kill(); // Kill old def
+ else CODE.add(old_def); // Else old lost a use, so onto worklist
+ }
+ moveDepsToWorklist();
+ // Return new_def for easy flow-coding
+ return new_def;
+ }
+
+ // Remove the numbered input, compressing the inputs in-place. This
+ // shuffles the order deterministically - which is suitable for Region and
+ // Phi, but not for every Node. If the def goes dead, it is recursively
+ // killed, which may include 'this' Node.
+ Node delDef(int idx) {
+ unlock();
+ Node old_def = in(idx);
+ _inputs.del(idx);
+ if( old_def.delUse(this) ) // If we removed the last use, the old def is now dead
+ old_def.kill(); // Kill old def
+ old_def.moveDepsToWorklist();
+ return this;
+ }
+
+ // Insert the numbered input, sliding other inputs to the right
+ Node insertDef(int idx, Node new_def) {
+ _inputs.add(idx,null);
+ return setDef(idx,new_def);
+ }
+
+
+ /**
+ * Add a new def to an existing Node. Keep the edges correct by
+ * adding the corresponding <em>def->use</em> edge.
+ *
+ * @param new_def the new definition, appended to the end of existing definitions
+ * @return new_def for flow coding
+ */
+ public Node addDef(Node new_def) {
+ unlock();
+ // Add use->def edge
+ _inputs.add(new_def);
+ // If new def is not null, add the corresponding def->use edge
+ if( new_def != null )
+ new_def.addUse(this);
+ return new_def;
+ }
+
+ // Breaks the edge invariants, used temporarily
+ protected <N extends Node> N addUse(Node n) { _outputs.add(n); return (N)this; }
+
+ // Remove node 'use' from 'def's (i.e. our) output list, by compressing the list in-place.
+ // Return true if the output list is empty afterward.
+ // Error is 'use' does not exist; ok for 'use' to be null.
+ protected boolean delUse( Node use ) {
+ _outputs.del(_outputs.find(use));
+ return _outputs.isEmpty();
+ }
+
+ // Shortcut for "popping" until n nodes. A "pop" is basically a
+ // setDef(last,null) followed by lowering the nIns() count.
+ void popUntil(int n) {
+ unlock();
+ while( nIns() > n ) {
+ Node old_def = _inputs.pop();
+ if( old_def != null && // If it exists and
+ old_def.delUse(this) ) // If we removed the last use, the old def is now dead
+ old_def.kill(); // Kill old def
+ }
+ }
+
+ /**
+ * Kill a Node with no <em>uses</em>, by setting all of its <em>defs</em>
+ * to null. This may recursively kill more Nodes, and is basically dead
+ * code elimination.
+ */
+ public void kill( ) {
+ unlock();
+ moveDepsToWorklist();
+ assert isUnused(); // Has no uses, so it is dead
+ _type=null; // Flag as dead
+ while( nIns()>0 ) { // Set all inputs to null, recursively killing unused Nodes
+ Node old_def = _inputs.removeLast();
+ // Revisit neighbor because removed use
+ if( old_def != null && CODE.add(old_def).delUse(this) )
+ old_def.kill(); // If we removed the last use, the old def is now dead
+ }
+ assert isDead(); // Really dead now
+ }
+
+ // Mostly used for asserts and printing.
+ public boolean isDead() { return isUnused() && nIns()==0 && _type==null; }
+
+ // Shortcuts to stop DCE mid-parse
+ // Add bogus null use to keep node alive
+ public <N extends Node> N keep() { return addUse(null); }
+ // Remove bogus null.
+ public <N extends Node> N unkeep() {
+ delUse(null);
+ return (N)this;
+ }
+ // Test "keep" status
+ public boolean iskeep() { return _outputs.find(null) != -1; }
+ public void unkill() {
+ if( unkeep().isUnused() )
+ kill();
+ }
+
+
+ // Replace self with nnn in the graph, making 'this' go dead
+ public void subsume( Node nnn ) {
+ assert nnn!=this;
+ while( nOuts() > 0 ) {
+ Node n = _outputs.removeLast();
+ n.unlock();
+ int idx = n._inputs.find(this);
+ n._inputs.set(idx,nnn);
+ nnn.addUse(n);
+ CODE.addAll(n._outputs);
+ }
+ kill();
+ }
+
+ // ------------------------------------------------------------------------
+ // Graph-based optimizations
+
+ /**
+ * Try to peephole at this node and return a better replacement Node.
+ * Always returns some not-null Node (often this).
+ */
+ public final Node peephole( ) {
+ if( _type==null ) // Brand-new node, never peeped before
+ JSViewer.show();
+ Node n = peepholeOpt();
+ if( n!=null ) // Made progress?
+ JSViewer.show(); // Show again
+ return n==null ? this : deadCodeElim(n._nid >= _nid ? n.peephole() : n); // Cannot return null for no-progress
+ }
+
+ /**
+ * Try to peephole at this node and return a better replacement Node if
+ * possible. We compute a {@link Type} and then check and replace:
+ * <ul>
+ * <li>if the Type {@link Type#isConstant}, we replace with a {@link ConstantNode}</li>
+ * <li>in a future chapter we will look for a
+ * <a href="https://en.wikipedia.org/wiki/Common_subexpression_elimination">Common Subexpression</a>
+ * to eliminate.</li>
+ * <li>we ask the Node for a better replacement. The "better replacement"
+ * is things like {@code (1+2)} becomes {@code 3} and {@code (1+(x+2))} becomes
+ * {@code (x+(1+2))}. By canonicalizing expressions we fold common addressing
+ * math constants, remove algebraic identities and generally simplify the
+ * code. </li>
+ *
+ * Unlike peephole above, this explicitly returns null for no-change, or not-null
+ * for a better replacement (which can be this).
+ * </ul>
+ */
+ public final Node peepholeOpt( ) {
+ CODE.iterCnt();
+ // Compute initial or improved Type
+ Type old = setType(compute());
+
+ // Replace constant computations from non-constants with a constant
+ // node. If peeps are disabled, still allow high Phis to collapse;
+ // they typically come from dead Regions, and we want the Region to
+ // collapse, which requires the Phis to die first.
+ if( _type.isHighOrConst() && !isConst() )
+ return ConstantNode.make(_type).peephole();
+
+ // Global Value Numbering
+ if( _hash==0 ) {
+ Node n = CODE._gvn.get(this); // Will set _hash as a side effect
+ if( n==null )
+ CODE._gvn.put(this,this); // Put in table now
+ else {
+ // Because of random worklist ordering, the two equal nodes
+ // might have different types. Because of monotonicity, both
+ // types are valid. To preserve monotonicity, the resulting
+ // shared Node has to have the best of both types.
+ n.setType(n._type.join(_type));
+ _hash = 0; // Clear, since it never went in the table
+ return deadCodeElim(n);// Return previous; does Common Subexpression Elimination
+ }
+ }
+
+ // Ask each node for a better replacement
+ Node n = idealize();
+ if( n != null ) // Something changed
+ return n; // Report progress
+
+ if( old!=_type ) return this; // Report progress;
+ CODE.iterNop();
+ return null; // No progress
+ }
+
+ // m is the new Node, self is the old.
+ // Return 'm', which may have zero uses but is alive nonetheless.
+ // If self has zero uses (and is not 'm'), {@link #kill} self.
+ private Node deadCodeElim(Node m) {
+ // If self is going dead and not being returned here (Nodes returned
+ // from peephole commonly have no uses (yet)), then kill self.
+ if( m != this && isUnused() && !isDead() ) {
+ // Killing self - and since self recursively kills self's inputs we
+ // might end up killing 'm', which we are returning as a live Node.
+ // So we add a bogus extra null output edge to stop kill().
+ m.keep(); // Keep m alive
+ kill(); // Kill self because replacing with 'm'
+ m.unkeep(); // Okay to peephole m
+ }
+ return m;
+ }
+
+ /**
+ * This function needs to be
+ * <a href="https://en.wikipedia.org/wiki/Monotonic_function">Monotonic</a>
+ * as it is part of a Monotone Analysis Framework.
+ * <a href="https://www.cse.psu.edu/~gxt29/teaching/cse597s21/slides/08monotoneFramework.pdf">See for example this set of slides</a>.
+ * <p>
+ * For Chapter 2, all our Types are really integer constants, and so all
+ * the needed properties are trivially true, and we can ignore the high
+ * theory. Much later on, this will become important and allow us to do
+ * many fancy complex optimizations trivially... because theory.
+ * <p>
+ * {@link #compute()} needs to be stand-alone, and cannot recursively call compute
+ * on its inputs, because programs are cyclic (have loops!) and this will just
+ * infinitely recurse until stack overflow. Instead, compute typically
+ * computes a new type from the {@link #_type} field of its inputs.
+ */
+ public abstract Type compute();
+
+ // Set the type. Assert monotonic progress.
+ // If changing, add users to worklist.
+ public Type setType(Type type) {
+ Type old = _type;
+ assert old==null || type.isa(old); // Since _type not set, can just re-run this in assert in the debugger
+ if( old == type ) return old;
+ _type = type; // Set _type late for easier assert debugging
+ CODE.addAll(_outputs);
+ moveDepsToWorklist();
+ return old;
+ }
+
+ public <N extends Node> N init() { _type = compute(); return (N)this; }
+
+ /**
+ * This function rewrites the current Node into a more "idealized" form.
+ * This is the bulk of our peephole rewrite rules, and we use this to
+ * e.g. turn arbitrary collections of adds and multiplies with mixed
+ * constants into a normal form that's easy for hardware to implement.
+ * Example: An array addressing expression:
+ * <pre> ary[idx+1]</pre>
+ * might turn into Sea-of-Nodes IR:
+ * <pre> (ary+12)+((idx+1) * 4)</pre>
+ * This expression can then be idealized into:
+ * <pre> ary + ((idx*4) + (12 + (1*4)))</pre>
+ * And more folding:
+ * <pre> ary + ((idx<<2) + 16)</pre>
+ * And during code-gen:
+ * <pre> MOV4 Rary,[Ridx<<2 +16] // or some such hardware-specific notation </pre>
+ * <p>
+ * {@link #idealize} has a very specific calling convention:
+ * <ul>
+ * <li>If NO change is made, return {@code null}
+ * <li>If ANY change is made, return not-null; this can be {@code this}
+ * <li>The returned Node does NOT call {@link #peephole} on itself; the {@link #peephole} call will recursively peephole it.
+ * <li>Any NEW nodes that are not directly returned DO call {@link #peephole}.
+ * </ul>
+ * <p>
+ * Examples:
+ * <table border="3">
+ * <tr><th> before </th><th> after </th><th>return </th><th>comment </th></tr>
+ * <tr><td>{@code (x+5) }</td><td>{@code (x+5) }</td><td>{@code null }</td><td>No change</td></tr>
+ * <tr><td>{@code (5+x) }</td><td>{@code (x+5) }</td><td>{@code this }</td><td>Swapped arguments</td></tr>
+ * <tr><td>{@code ((x+1)+2)}</td><td>{@code (x+(1+2))}</td><td>{@code (x+_) }</td><td>Returns 2 new Nodes</td></tr>
+ * </table>
+ *
+ * The last entry deserves more discussion. The new Node {@code (1+2)}
+ * created in {@link #idealize} calls {@link #peephole} (which then folds
+ * into a constant). The other new Node {@code (x+3)} does not call
+ * peephole, because it is returned and peephole itself will recursively
+ * call peephole.
+ * <p>
+ * Since idealize calls peephole and peephole calls idealize, you must be
+ * careful that all idealizations are <em>monotonic</em>: all transforms
+ * remove some feature, so that the set of available transforms always
+ * shrinks. If you don't, you risk an infinite peephole loop!
+ *
+ * @return Either a new or changed node, or null for no changes.
+ */
+ public abstract Node idealize();
+
+
+ // Some of the peephole rules get complex, and search further afield than
+ // just the nearest neighbor. These peepholes can fail the pattern match
+ // on a node some distance away, and if that node ever changes we should
+ // retry the peephole. Track a set of Nodes dependent on `this`, and
+ // revisit them if `this` changes.
+ Ary<Node> _deps;
+
+ /**
+ * Add a node to the list of dependencies. Only add it if its not an input
+ * or output of this node, that is, it is at least one step away. The node
+ * being added must benefit from this node being peepholed.
+ */
+ Node addDep( Node dep ) {
+ // Running peepholes during the big assert cannot have side effects
+ // like adding dependencies.
+ if( CODE._midAssert ) return this;
+ if( dep == null ) return this;
+ if( _deps==null ) _deps = new Ary<>(Node.class);
+ if( _deps .find(dep) != -1 ) return this; // Already on list
+ if( _inputs .find(dep) != -1 ) return this; // No need for deps on immediate neighbors
+ if( _outputs.find(dep) != -1 ) return this;
+ _deps.add(dep);
+ return this;
+ }
+
+ // Move the dependents onto a worklist, and clear for future dependents.
+ public void moveDepsToWorklist( ) {
+ if( _deps==null ) return;
+ CODE.addAll(_deps);
+ _deps.clear();
+ }
+
+
+ // Two nodes are equal if they have the same inputs and the same "opcode"
+ // which means the same Java class, plus same internal parts.
+ @Override public final boolean equals( Object o ) {
+ if( o==this ) return true;
+ if( o.getClass() != getClass() ) return false;
+ Node n = (Node)o;
+ int len = _inputs.size();
+ if( len != n._inputs.size() ) return false;
+ for( int i=0; i<len; i++ )
+ if( in(i) != n.in(i) )
+ return false;
+ return eq(n);
+ }
+ // Subclasses add extra checks (such as ConstantNodes have same constant),
+ // and can assume "this!=n" and has the same Java class.
+ boolean eq( Node n ) { return true; }
+
+
+ // Cached hash. If zero, then not computed AND this Node is NOT in the GVN
+ // table - and can have its edges hacked (which will change his hash
+ // anyway). If Non-Zero then this Node is IN the GVN table, or is being
+ // probed to see if it can be inserted. His edges are "locked", because
+ // hacking his edges will change his hash.
+ int _hash;
+
+ // If the _hash is set, then the Node is in the GVN table; remove it.
+ void unlock() {
+ if( _hash==0 ) return;
+ Node old = CODE._gvn.remove(this); // Pull from table
+ assert old==this;
+ _hash=0; // Out of table now
+ }
+
+
+ // Hash of opcode and inputs
+ @Override public final int hashCode() {
+ if( _hash != 0 ) return _hash;
+ int hash = hash();
+ for( Node n : _inputs )
+ if( n != null )
+ hash = hash ^ (hash<<17) ^ (hash>>13) ^ n._nid;
+ if( hash==0 ) hash = 0xDEADBEEF; // Bad hash, so use some junky thing
+ return (_hash=hash);
+ }
+ // Subclasses add extra hash info (such as ConstantNodes constant)
+ int hash() { return 0; }
+
+ // ------------------------------------------------------------------------
+ //
+
+ /** Is this Node Memory related */
+ public boolean isMem() { return false; }
+
+ /** Pinned in the schedule; these are data nodes whose input#0 is not allowed to change */
+ public boolean isPinned() { return false; }
+
+ // Semantic change to the graph (so NOT a peephole), used by the Parser.
+ // If any input is a float, flip to a float-flavored opcode and widen any
+ // non-float input.
+ public final Node widen() {
+ if( !hasFloatInput() ) return this;
+ Node flt = copyF();
+ if( flt==null ) return this;
+ for( int i=1; i<nIns(); i++ )
+ flt.setDef(i, in(i)._type instanceof TypeFloat ? in(i) : new ToFloatNode(in(i)).peephole());
+ kill();
+ return flt;
+ }
+ private boolean hasFloatInput() {
+ for( int i=1; i<nIns(); i++ )
+ if( in(i)._type instanceof TypeFloat )
+ return true;
+ return false;
+ }
+ Node copyF() { return null; }
+
+
+ // ------------------------------------------------------------------------
+ // Peephole utilities
+
+ // Swap inputs without letting either input go dead during the swap.
+ Node swap12() {
+ unlock(); // Hash is order dependent
+ _inputs.swap(1,2);
+ return this;
+ }
+
+ /**
+ * Does this node contain all constants? Ignores in(0), as is usually
+ * control. In an input is not a constant, we add dep as a dependency to
+ * it because dep can make progress if the input becomes a constant later.
+ * It is sufficient for one of the non-const inputs to have the dependency,
+ * so we don't bother checking the rest.
+ */
+ boolean allCons(Node dep) {
+ for( int i=1; i<nIns(); i++ )
+ if( !(in(i)._type.isConstant()) ) {
+ in(i).addDep(dep); // If in(i) becomes a constant later, will trigger some peephole
+ return false;
+ }
+ return true;
+ }
+
+
+ // Make a shallow copy (same class) of this Node, with given inputs and
+ // empty outputs and a new Node ID. The original inputs are ignored.
+ // Does not need to be implemented in isCFG() nodes.
+ Node copy(Node lhs, Node rhs) { throw Utils.TODO("Binary ops need to implement copy"); }
+
+ // Report any post-optimize errors
+ public Parser.ParseException err() { return null; }
+
+ // Common integer constants
+ public static ConstantNode con(long x) { return (ConstantNode)(new ConstantNode(TypeInteger.constant(x)).peephole()); }
+
+ // Utility to walk the entire graph applying a function; return the first
+ // not-null result.
+ final public <E> E walk( Function<Node,E> pred ) {
+ assert CODE._visit.isEmpty();
+ E rez = _walk(pred);
+ CODE._visit.clear();
+ return rez;
+ }
+
+ private <E> E _walk( Function<Node,E> pred ) {
+ if( CODE._visit.get(_nid) ) return null; // Been there, done that
+ CODE._visit.set(_nid);
+ E x = pred.apply(this);
+ if( x != null ) return x;
+ for( Node def : _inputs ) if( def != null && (x = def._walk(pred)) != null ) return x;
+ for( Node use : _outputs ) if( use != null && (x = use._walk(pred)) != null ) return x;
+ return null;
+ }
+
+ /**
+ * Debugging utility to find a Node by index
+ */
+ public Node find(int nid) {
+ return walk( n -> n._nid==nid ? n : null );
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/NotNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/NotNode.java
new file mode 100644
index 00000000..b454de66
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/NotNode.java
@@ -0,0 +1,32 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+
+public class NotNode extends Node {
+ public NotNode(Node in) { super(null, in); }
+
+ @Override public String label() { return "Not"; }
+
+ @Override public String glabel() { return "!"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("(!"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public TypeInteger compute() {
+ Type t0 = in(1)._type;
+ if( t0.isHigh() ) return TypeInteger.BOOL.dual();
+ if( t0 == Type.NIL || t0 == TypeInteger.ZERO ) return TypeInteger.TRUE;
+ if( t0 instanceof TypeNil tn && tn.notNull() ) return TypeInteger.FALSE;
+ if( t0 instanceof TypeInteger i && (i._min > 0 || i._max < 0) ) return TypeInteger.FALSE;
+ return TypeInteger.BOOL;
+ }
+
+ @Override
+ public Node idealize() { return null; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/OrNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/OrNode.java
new file mode 100644
index 00000000..9b03dc5d
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/OrNode.java
@@ -0,0 +1,55 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+
+import java.util.BitSet;
+
+public class OrNode extends LogicalNode {
+ public OrNode(Parser.Lexer loc, Node lhs, Node rhs) { super(loc, lhs, rhs); }
+
+ @Override public String label() { return "Or"; }
+ @Override public String op() { return "|"; }
+
+ @Override public String glabel() { return "|"; }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if( t1 instanceof TypeInteger i0 &&
+ t2 instanceof TypeInteger i1 ) {
+ if( i0.isConstant() && i1.isConstant() )
+ return TypeInteger.constant(i0.value()|i1.value());
+ }
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t1 = lhs._type;
+ Type t2 = rhs._type;
+
+ // Or of 0. We do not check for (0|x) because this will already
+ // canonicalize to (x|0)
+ if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==0 )
+ return lhs;
+
+ // Move constants to RHS: con*arg becomes arg*con
+ if ( t1.isConstant() && !t2.isConstant() )
+ return swap12();
+
+ // Do we have ((x | (phi cons)) | con) ?
+ // Do we have ((x | (phi cons)) | (phi cons)) ?
+ // Push constant up through the phi: x | (phi con0|con0 con1|con1...)
+ Node phicon = AddNode.phiCon(this,true);
+ if( phicon!=null ) return phicon;
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new OrNode(_loc,lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ParmNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ParmNode.java
new file mode 100644
index 00000000..8d7c4205
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ParmNode.java
@@ -0,0 +1,48 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.Type;
+import java.util.BitSet;
+
+public class ParmNode extends PhiNode {
+
+ // Argument indices are mapped one-to-one on CallNode inputs
+ public final int _idx; // Argument index
+
+ public ParmNode(String label, int idx, Type declaredType, Node... inputs) {
+ super(label,declaredType,inputs);
+ _idx = idx;
+ }
+ public ParmNode(ParmNode parm) { super(parm, parm._label, parm._declaredType); _idx = parm._idx; }
+
+ @Override public String label() { return MemOpNode.mlabel(_label); }
+
+ @Override public String glabel() { return _label; }
+
+ public FunNode fun() { return (FunNode)in(0); }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ if( "main".equals(fun()._name) && _label.equals("arg") )
+ return sb.append("arg");
+ sb.append("Parm_").append(_label).append("(");
+ for( Node in : _inputs ) {
+ if (in == null) sb.append("____");
+ else in._print0(sb, visited);
+ sb.append(",");
+ }
+ sb.setLength(sb.length()-1);
+ sb.append(")");
+ return sb;
+ }
+
+
+ @Override
+ public Node idealize() {
+ if( inProgress() ) return null;
+ return super.idealize();
+ }
+
+ // Always in-progress until we run out of unknown callers
+ @Override public boolean inProgress() { return fun().inProgress(); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/PhiNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/PhiNode.java
new file mode 100644
index 00000000..17748afe
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/PhiNode.java
@@ -0,0 +1,201 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+
+public class PhiNode extends Node {
+
+ public final String _label;
+
+ // The Phi type we compute must stay within the domain of the Phi.
+ // Example Int stays Int, Ptr stays Ptr, Control stays Control, Mem stays Mem.
+ final Type _declaredType;
+
+ public PhiNode(String label, Type declaredType, Node... inputs) { super(inputs); _label = label; assert declaredType!=null; _declaredType = declaredType; }
+ public PhiNode(PhiNode phi, String label, Type declaredType) { super(phi); _label = label; _declaredType = declaredType; }
+ public PhiNode(PhiNode phi) { super(phi); _label = phi._label; _declaredType = phi._declaredType; }
+
+ public PhiNode(RegionNode r, Node sample) {
+ super(new Node[]{r});
+ _label = "";
+ _declaredType = sample._type;
+ while( nIns() < r.nIns() )
+ addDef(sample);
+ }
+
+ @Override public String label() { return "Phi_"+MemOpNode.mlabel(_label); }
+
+ @Override public String glabel() { return "&phi;_"+_label; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ if( !(region() instanceof RegionNode r) || r.inProgress() )
+ sb.append("Z");
+ sb.append("Phi(");
+ for( Node in : _inputs ) {
+ if (in == null) sb.append("____");
+ else in._print0(sb, visited);
+ sb.append(",");
+ }
+ sb.setLength(sb.length()-1);
+ sb.append(")");
+ return sb;
+ }
+
+ public CFGNode region() { return (CFGNode)in(0); }
+ @Override public boolean isMultiTail() { return true; }
+ @Override public boolean isMem() { return _declaredType instanceof TypeMem; }
+ @Override public boolean isPinned() { return true; }
+
+ @Override
+ public Type compute() {
+ if( !(region() instanceof RegionNode r) )
+ return region()._type==Type.XCONTROL ? (_type instanceof TypeMem ? TypeMem.TOP : Type.TOP) : _type;
+ // During parsing Phis have to be computed type pessimistically.
+ if( r.inProgress() ) return _declaredType;
+ // Set type to local top of the starting type
+ Type t = _declaredType.glb().dual();//Type.TOP;
+ for (int i = 1; i < nIns(); i++)
+ // If the region's control input is live, add this as a dependency
+ // to the control because we can be peeped should it become dead.
+ if( r.in(i).addDep(this)._type != Type.XCONTROL )
+ t = t.meet(in(i)._type);
+ return t;
+ }
+
+ @Override
+ public Node idealize() {
+ if( !(region() instanceof RegionNode r ) )
+ return in(1); // Input has collapse to e.g. starting control.
+ if( r.inProgress() || r.nIns()<=1 )
+ return null; // Input is in-progress
+
+ // If we have only a single unique input, become it.
+ Node live = singleUniqueInput();
+ if (live != null)
+ return live;
+
+ // No bother if region is going to fold dead paths soon
+ for( int i=1; i<nIns(); i++ )
+ if( r.in(i)._type == Type.XCONTROL )
+ return null;
+
+ // Pull "down" a common data op. One less op in the world. One more
+ // Phi, but Phis do not make code.
+ // Phi(op(A,B),op(Q,R),op(X,Y)) becomes
+ // op(Phi(A,Q,X), Phi(B,R,Y)).
+ Node op = in(1);
+ if( !isMem() && op.nIns()==3 && op.in(0)==null && same_op() ) {
+ assert !(op instanceof CFGNode);
+ Node[] lhss = new Node[nIns()];
+ Node[] rhss = new Node[nIns()];
+ lhss[0] = rhss[0] = in(0); // Set Region
+ for( int i=1; i<nIns(); i++ ) {
+ lhss[i] = in(i).in(1);
+ rhss[i] = in(i).in(2);
+ }
+ Node phi_lhs = new PhiNode(_label, _declaredType,lhss).peephole();
+ Node phi_rhs = new PhiNode(_label, _declaredType,rhss).peephole();
+ Node down = op.copy(phi_lhs,phi_rhs);
+ // Test not running backwards, which can happen for e.g. And's
+ if( down.compute().isa(compute()) )
+ return down;
+ down.kill();
+ }
+
+ // If merging Phi(N, cast(N)) - we are losing the cast JOIN effects, so just remove.
+ if( nIns()==3 ) {
+ if( in(1) instanceof CastNode cast && cast.in(1).addDep(this)==in(2) ) return in(2);
+ if( in(2) instanceof CastNode cast && cast.in(1).addDep(this)==in(1) ) return in(1);
+ }
+ // If merging a null-checked null and the checked value, just use the value.
+ // if( val ) ..; phi(Region,False=0/null,True=val);
+ // then replace with plain val.
+ if( nIns()==3 ) {
+ int nullx = -1;
+ if( in(1)._type == in(1)._type.makeZero() ) nullx = 1;
+ if( in(2)._type == in(2)._type.makeZero() ) nullx = 2;
+ if( nullx != -1 ) {
+ Node val = in(3-nullx);
+ if( val instanceof CastNode cast )
+ val = cast.in(1);
+ if( r.idom(this).addDep(this) instanceof IfNode iff && iff.pred().addDep(this)==val ) {
+ // Must walk the idom on the null side to make sure we hit False.
+ CFGNode idom = (CFGNode)r.in(nullx);
+ while( idom != null && idom.nIns() > 0 && idom.in(0) != iff ) idom = idom.idom();
+ if( idom instanceof CProjNode proj && proj._idx==1 )
+ return val;
+ }
+ }
+ }
+
+ return null;
+ }
+
+ private boolean same_op() {
+ for( int i=2; i<nIns(); i++ )
+ if( in(1).getClass() != in(i).getClass() )
+ return false;
+ return true;
+ }
+
+ /**
+ * If only single unique input, return it
+ */
+ private Node singleUniqueInput() {
+ if( region() instanceof LoopNode loop && loop.entry()._type == Type.XCONTROL )
+ return null; // Dead entry loops just ignore and let the loop collapse
+ Node live = null;
+ for( int i=1; i<nIns(); i++ ) {
+ // If the region's control input is live, add this as a dependency
+ // to the control because we can be peeped should it become dead.
+ if( region().in(i).addDep(this)._type != Type.XCONTROL && in(i) != this )
+ if( live == null || live == in(i) ) live = in(i);
+ else return null;
+ }
+ return live;
+ }
+
+ @Override
+ boolean allCons(Node dep) {
+ if( !(region() instanceof RegionNode r) ) return false;
+ // When the region completes (is no longer in progress) the Phi can
+ // become a "all constants" Phi, and the "dep" might make progress.
+ addDep(dep);
+ if( r.inProgress() ) return false;
+ return super.allCons(dep);
+ }
+
+ // True if last input is null
+ public boolean inProgress() {
+ return in(nIns()-1) == null;
+ }
+
+ // Never equal if inProgress
+ @Override boolean eq( Node n ) {
+ return !inProgress();
+ }
+
+ @Override
+ public Parser.ParseException err() {
+ if( _type != Type.BOTTOM ) return null;
+
+ // BOTTOM means we mixed e.g. int and ptr
+ for( int i=1; i<nIns(); i++ )
+ // Already an error, but better error messages come from elsewhere
+ if( in(i)._type == Type.BOTTOM )
+ return null;
+
+ // Gather a minimal set of types that "cover" all the rest
+ boolean ti=false, tf=false, tp=false, tn=false;
+ for( int i=1; i<nIns(); i++ ) {
+ Type t = in(i)._type;
+ ti |= t instanceof TypeInteger x;
+ tf |= t instanceof TypeFloat x;
+ tp |= t instanceof TypeMemPtr x;
+ tn |= t==Type.NIL;
+ }
+ return ReturnNode.mixerr(ti,tf,tp,tn, ((RegionNode)region())._loc);
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ProjNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ProjNode.java
new file mode 100644
index 00000000..ef7b17e4
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ProjNode.java
@@ -0,0 +1,55 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeMem;
+import com.seaofnodes.simple.type.TypeTuple;
+
+import java.util.BitSet;
+
+public class ProjNode extends Node {
+
+ // Which slice of the incoming multipart value
+ public final int _idx;
+
+ // Debugging label
+ public final String _label;
+
+ public ProjNode(Node ctrl, int idx, String label) {
+ super(new Node[]{ctrl});
+ _idx = idx;
+ _label = label;
+ }
+ public ProjNode(ProjNode p) { super(p); _idx = p._idx; _label = p._label; }
+
+ @Override public String label() { return _label; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ if( _label != null ) return sb.append(_label);
+ if( in(0) instanceof CallEndNode cend && cend.call()!=null )
+ return cend.call()._print0(sb,visited);
+ return sb.append("LONELY PROJ");
+ }
+
+ @Override public CFGNode cfg0() {
+ return in(0) instanceof CFGNode cfg ? cfg : in(0).cfg0();
+ }
+
+ @Override public boolean isMultiTail() { return in(0).isMultiHead(); }
+ @Override public boolean isMem() { return _type instanceof TypeMem; }
+ @Override public boolean isPinned() { return true; }
+
+ @Override
+ public Type compute() {
+ Type t = in(0)._type;
+ return t instanceof TypeTuple tt ? tt._types[_idx] : Type.BOTTOM;
+ }
+
+ @Override public Node idealize() { return ((MultiNode)in(0)).pcopy(_idx); }
+
+ @Override
+ boolean eq( Node n ) { return _idx == ((ProjNode)n)._idx; }
+
+ @Override
+ int hash() { return _idx; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ReadOnlyNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ReadOnlyNode.java
new file mode 100644
index 00000000..b755af3f
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ReadOnlyNode.java
@@ -0,0 +1,30 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeMemPtr;
+
+import java.util.BitSet;
+
+/**
+ * Cast a pointer to read-only
+ */
+public class ReadOnlyNode extends Node {
+ public ReadOnlyNode( Node n ) { super(null,n); }
+ public ReadOnlyNode( ReadOnlyNode n ) { super(n); }
+ @Override public String label() { return "ReadOnly"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ return in(1)._print0(sb.append("(const)"),visited);
+ }
+ @Override public Type compute() {
+ Type t = in(1)._type;
+ return t instanceof TypeMemPtr tmp ? tmp.makeRO() : t;
+ }
+
+ @Override public Node idealize() {
+ if( in(1)._type instanceof TypeMemPtr tmp && tmp.isFinal() )
+ return in(1);
+ return null;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/RegionNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/RegionNode.java
new file mode 100644
index 00000000..5d3db5c6
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/RegionNode.java
@@ -0,0 +1,126 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.type.Type;
+import java.util.*;
+
+public class RegionNode extends CFGNode {
+ // Source location for late discovered errors
+ public Parser.Lexer _loc;
+
+ public RegionNode(Parser.Lexer loc, Node... nodes) { super(nodes); _loc = loc; }
+ public RegionNode(RegionNode r, Parser.Lexer loc) { super(r); _loc = loc; }
+ public RegionNode(RegionNode r) { super(r); _loc = r._loc; }
+
+ @Override
+ public String label() { return "Region"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ return sb.append(label());
+ }
+
+ @Override public boolean isMultiHead() { return true; }
+ @Override public boolean blockHead() { return true; }
+
+ @Override
+ public Type compute() {
+ if( inProgress() ) return Type.CONTROL;
+ Type t = Type.XCONTROL;
+ for (int i = 1; i < nIns(); i++)
+ t = t.meet(in(i)._type);
+ return t;
+ }
+
+ @Override
+ public Node idealize() {
+ if( inProgress() ) return null;
+
+ Node progress = deadPath();
+ if( progress!=null ) return progress;
+
+ // If down to a single input, become that input
+ if( nIns()==2 && !hasPhi() )
+ return in(1); // Collapse if no Phis; 1-input Phis will collapse on their own
+
+ // If a CFG diamond with no merging, delete: "if( pred ) {} else {};"
+ if( !hasPhi() && // No Phi users, just a control user
+ in(1) instanceof CProjNode p1 &&
+ in(2) instanceof CProjNode p2 &&
+ p1.in(0).addDep(this)==p2.in(0).addDep(this) &&
+ p1.in(0) instanceof IfNode iff ) {
+ // Replace with the iff.ctrl directly
+ if( nIns()==3 ) return iff.ctrl();
+ // Just delete the path for fat Regions
+ setDef(1,iff.ctrl());
+ return delDef(2);
+ }
+
+ return null;
+ }
+
+ Node deadPath() {
+ // Delete dead paths into a Region
+ int path = findDeadInput();
+ if( path==0 ) return null;
+ // Do not delete the entry path of a loop (ok to remove the back edge
+ // and make the loop a single-entry Region which folds away the Loop).
+ // Folding the entry path confused the loop structure, moving the
+ // backedge to the entry point.
+ if( this instanceof LoopNode loop && loop.entry()==in(path) )
+ return null;
+ // Cannot use the obvious output iterator here, because a Phi deleting
+ // an input might recursively delete *itself*. This shuffles the
+ // output array, and we might miss iterating an unrelated Phi. So on
+ // rare occasions we repeat the loop to get all the Phis.
+ int nouts = 0;
+ while( nouts != nOuts() ) {
+ nouts = nOuts();
+ for( int i=0; i<nOuts(); i++ )
+ if( out(i) instanceof PhiNode phi && phi.nIns()==nIns() )
+ CodeGen.CODE.addAll(phi.delDef(path)._outputs);
+ }
+ return isDead() ? Parser.XCTRL : delDef(path);
+ }
+
+
+ private int findDeadInput() {
+ for( int i=1; i<nIns(); i++ )
+ if( in(i)._type==Type.XCONTROL )
+ return i;
+ return 0; // All inputs alive
+ }
+
+ boolean hasPhi() {
+ for( Node phi : _outputs )
+ if( phi instanceof PhiNode )
+ return true;
+ return false;
+ }
+
+ // Immediate dominator of Region is a little more complicated.
+ @Override public int idepth() {
+ if( _idepth!=0 ) return _idepth;
+ int d=0;
+ for( Node n : _inputs )
+ if( n!=null )
+ d = Math.max(d,((CFGNode)n).idepth()+1);
+ return _idepth=d;
+ }
+
+ @Override public CFGNode idom(Node dep) {
+ CFGNode lca = null;
+ // Walk the LHS & RHS idom trees in parallel until they match, or either fails.
+ // Because this does not cache, it can be linear in the size of the program.
+ for( int i=1; i<nIns(); i++ )
+ lca = cfg(i)._idom(lca,dep);
+ return lca;
+ }
+
+ // True if last input is null
+ public boolean inProgress() { return nIns()>1 && in(nIns()-1) == null; }
+
+ // Never equal if inProgress
+ @Override boolean eq( Node n ) { return !inProgress(); }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ReturnNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ReturnNode.java
new file mode 100644
index 00000000..20b6c7b9
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ReturnNode.java
@@ -0,0 +1,129 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+
+/**
+ * The Return node has two inputs. The first input is a control node and the
+ * second is the data node that supplies the return value.
+ * <p>
+ * In this presentation, Return functions as a Stop node, since multiple <code>return</code> statements are not possible.
+ * The Stop node will be introduced in Chapter 6 when we implement <code>if</code> statements.
+ * <p>
+ * The Return's output is the value from the data node.
+ */
+public class ReturnNode extends CFGNode {
+
+ public FunNode _fun;
+
+ public ReturnNode(Node ctrl, Node mem, Node data, Node rpc, FunNode fun ) {
+ super(ctrl, mem, data, rpc);
+ _fun = fun;
+ }
+ public ReturnNode( ReturnNode ret, FunNode fun ) { super(ret); _fun = fun; }
+
+ public Node ctrl() { return in(0); }
+ public Node mem () { return in(1); }
+ public Node expr() { return in(2); }
+ public Node rpc () { return in(3); }
+ public FunNode fun() { return _fun; }
+
+ @Override
+ public String label() { return "Return"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ sb.append("return ");
+ expr()._print0(sb, visited);
+ return sb.append(";");
+ }
+
+ // No one unique control follows; can be many call end sites
+ @Override public CFGNode uctrl() { return null; }
+
+ @Override
+ public Type compute() {
+ if( inProgress () ) return TypeTuple.RET; // In progress
+ if( _fun.isDead() ) return TypeTuple.RET.dual(); // Dead another way
+ return TypeTuple.make(ctrl()._type,mem()._type,expr()._type);
+ }
+
+ @Override public Node idealize() {
+ if( inProgress () ) return null;
+ if( _fun.isDead() ) return null;
+
+ // Upgrade signature based on return type
+ Type ret = expr()._type;
+ TypeFunPtr fcn = _fun.sig();
+ assert ret.isa(fcn.ret());
+ if( ret != fcn.ret() )
+ _fun.setSig(fcn.makeFrom(ret));
+
+ // If dead (cant be reached; infinite loop), kill the exit values
+ if( ctrl()._type==Type.XCONTROL &&
+ !(mem() instanceof ConstantNode && expr() instanceof ConstantNode) ) {
+ Node top = new ConstantNode(Type.TOP).peephole();
+ setDef(1,top);
+ setDef(2,top);
+ return this;
+ }
+
+ return null;
+ }
+
+ public boolean inProgress() {
+ return ctrl().getClass() == RegionNode.class && ((RegionNode)ctrl()).inProgress();
+ }
+
+ // Gather parse-time return types for error reporting
+ private Type mt = Type.TOP;
+ private boolean ti=false, tf=false, tp=false, tn=false;
+
+ // Add a return exit to the current parsing function
+ void addReturn( Node ctrl, Node rmem, Node expr ) {
+ assert inProgress();
+
+ // Gather parse-time return types for error reporting
+ Type t = expr._type;
+ mt = mt.meet(t);
+ ti |= t instanceof TypeInteger x;
+ tf |= t instanceof TypeFloat x;
+ tp |= t instanceof TypeMemPtr x;
+ tn |= t==Type.NIL;
+
+ // Merge path into the One True Return
+ RegionNode r = (RegionNode)ctrl();
+ // Assert that the Phis are in particular outputs; not reordered or shuffled
+ PhiNode mem = (PhiNode)r.out(0); assert mem._declaredType == TypeMem.BOT;
+ PhiNode rez = (PhiNode)r.out(1); assert rez._declaredType == Type.BOTTOM;
+ // Pop "inProgress" null off
+ r ._inputs.pop();
+ mem._inputs.pop();
+ rez._inputs.pop();
+ // Add new return point
+ r .addDef(ctrl);
+ mem.addDef(rmem);
+ rez.addDef(expr);
+ // Back to being inProgress
+ r .addDef(null);
+ mem.addDef(null);
+ rez.addDef(null);
+ }
+
+ @Override public Parser.ParseException err() {
+ return expr()._type/*mt*/==Type.BOTTOM ? mixerr(ti,tf,tp,tn,_fun._loc) : null;
+ }
+
+ static Parser.ParseException mixerr( boolean ti, boolean tf, boolean tp, boolean tn, Parser.Lexer loc ) {
+ if( !ti && !tf && !tp && !tn )
+ return Parser.error("No defined return type", loc);
+ SB sb = new SB().p("No common type amongst ");
+ if( ti ) sb.p("int and ");
+ if( tf ) sb.p("f64 and ");
+ if( tp || tn ) sb.p("reference and ");
+ return Parser.error(sb.unchar(5).toString(),loc);
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/RoundF32Node.java b/chapter20/src/main/java/com/seaofnodes/simple/node/RoundF32Node.java
new file mode 100644
index 00000000..44d3a587
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/RoundF32Node.java
@@ -0,0 +1,38 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFloat;
+
+import java.util.BitSet;
+
+public class RoundF32Node extends Node {
+ public RoundF32Node(Node lhs) { super(null, lhs); }
+
+ @Override public String label() { return "RoundF32"; }
+
+ @Override public String glabel() { return "(f32)"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ return in(1)._print0(sb.append("((f32)"), visited).append(")");
+ }
+
+ @Override
+ public Type compute() {
+ if (in(1)._type instanceof TypeFloat i0 && i0.isConstant() )
+ return TypeFloat.constant((float)i0.value());
+ return in(1)._type;
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Type t1 = lhs._type;
+
+ // RoundF32 of float
+ if( t1 instanceof TypeFloat tf && tf._sz==32 )
+ return lhs;
+
+ return null;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/SarNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/SarNode.java
new file mode 100644
index 00000000..4a71ec06
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/SarNode.java
@@ -0,0 +1,50 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+public class SarNode extends LogicalNode {
+ public SarNode(Parser.Lexer loc, Node lhs, Node rhs) { super(loc, lhs, rhs); }
+
+ @Override public String label() { return "Sar"; }
+ @Override public String op() { return ">>"; }
+
+ @Override public String glabel() { return "&gt;&gt;"; }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if (t1 instanceof TypeInteger i0 &&
+ t2 instanceof TypeInteger i1) {
+ if( i0 == TypeInteger.ZERO )
+ return TypeInteger.ZERO;
+ if( i0.isConstant() && i1.isConstant() )
+ return TypeInteger.constant(i0.value()>>i1.value());
+ if( i1.isConstant() ) {
+ int log = (int)i1.value();
+ return TypeInteger.make(-1L<<(63-log),(1L<<(63-log))-1);
+ }
+ }
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t2 = rhs._type;
+
+ // Sar of 0.
+ if( t2.isConstant() && t2 instanceof TypeInteger i && (i.value()&63)==0 )
+ return lhs;
+
+ // TODO: x >> 3 >> (y ? 1 : 2) ==> x >> (y ? 4 : 5)
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new SarNode(_loc,lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ScopeNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ScopeNode.java
new file mode 100644
index 00000000..1208ff63
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ScopeNode.java
@@ -0,0 +1,428 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.type.*;
+import java.util.*;
+
+/**
+ * The Scope node is purely a parser helper - it tracks names to nodes with a
+ * stack of variables.
+ */
+public class ScopeNode extends MemMergeNode {
+
+ /**
+ * The control is a name that binds to the currently active control
+ * node in the graph
+ */
+ public static final String CTRL = "$ctrl";
+ public static final String ARG0 = "arg";
+ public static final String MEM0 = "$mem";
+
+ // All active/live variables in all nested scopes, all run together
+ public final Ary<Var> _vars;
+
+ // Size of each nested lexical scope
+ public final Ary<Integer> _lexSize;
+
+ // Lexical scope is one of normal Block, constructor or function
+ public enum Kind { Block, Constructor, Function };
+ public final Ary<Kind> _kinds;
+
+ // Extra guards; tested predicates and casted results
+ private final Ary<Node> _guards;
+
+ // A new ScopeNode
+ public ScopeNode() {
+ super(true);
+ _vars = new Ary<>(Var .class);
+ _lexSize= new Ary<>(Integer.class);
+ _kinds = new Ary<>(Kind .class);
+ _guards = new Ary<>(Node .class);
+ }
+
+ @Override public String label() { return "Scope"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ sb.append("Scope[ ");
+ int j=1;
+ for( int i=0; i<nIns(); i++ ) {
+ if( j < _lexSize._len && i == _lexSize.at(j) ) { sb.append("| "); j++; }
+ Var v = _vars.get(i);
+ sb.append(v.type().print(new SB()));
+ sb.append(" ");
+ if( v._final ) sb.append("!");
+ sb.append(v._name);
+ sb.append("=");
+ Node n = in(i);
+ while( n instanceof ScopeNode loop ) {
+ sb.append("Lazy_");
+ n = loop.in(i);
+ }
+ if( n==null ) sb.append("___");
+ else n._print0(sb, visited);
+ sb.append(", ");
+ }
+ sb.setLength(sb.length()-2);
+ return sb.append("]");
+ }
+
+
+ public Node ctrl() { return in(0); }
+ public MemMergeNode mem() { return (MemMergeNode)in(1); }
+
+ /**
+ * The ctrl of a ScopeNode is always bound to the currently active
+ * control node in the graph, via a special name '$ctrl' that is not
+ * a valid identifier in the language grammar and hence cannot be
+ * referenced in Simple code.
+ *
+ * @param n The node to be bound to '$ctrl'
+ *
+ * @return Node that was bound
+ */
+ public <N extends Node> N ctrl(N n) { return setDef(0,n); }
+ public Node mem(Node n) { return setDef(1,n); }
+
+ public void push(Kind kind) {
+ assert _lexSize._len==_kinds._len;
+ _lexSize.push(_vars.size());
+ _kinds .push(kind);
+ }
+
+ // Pop a lexical scope
+ public void pop() {
+ assert _lexSize._len==_kinds._len;
+ promote();
+ int n = _lexSize.pop();
+ _kinds.pop();
+ popUntil(n);
+ _vars.setLen(n);
+ }
+
+
+ // Look for forward references in the last lexical scope and promote to the
+ // next outer lexical scope. At the last scope declare them an error.
+ public void promote() {
+ int n = _lexSize.last();
+ for( int i=n; i<nIns(); i++ ) {
+ Var v = _vars.at(i);
+ if( !v.isFRef() ) continue;
+ if( _lexSize._len==1 )
+ throw Parser.error("Undefined name '" + v._name + "'",v._loc);
+ _vars.swap(n,i);
+ _inputs.swap(n,i);
+ v._idx = n;
+ n++;
+ _lexSize.set(_lexSize._len-1,n);
+ }
+ }
+
+
+ public boolean inCon() { return _kinds.last() == Kind.Constructor; }
+
+ // Is v outside any current function scope?
+ public boolean outOfFunction( Var v ) {
+ for( int i=_lexSize._len-1; i>=0 && v._idx<_lexSize.at(i); i-- )
+ if( _kinds.at(i)==Kind.Function )
+ return true;
+ return false;
+ }
+
+
+ // Find name in reverse, return an index into _vars or -1. Linear scan
+ // instead of hashtable, but probably doesn't matter until the scan
+ // typically hits many dozens of variables.
+ int find( String name ) {
+ for( int i=_vars.size()-1; i>=0; i-- )
+ if( _vars.at(i)._name.equals(name) )
+ return i;
+ return -1;
+ }
+
+ /**
+ * Create a new variable name in the current scope
+ */
+ public boolean define( String name, Type declaredType, boolean xfinal, Node init, Parser.Lexer loc ) {
+ assert _lexSize.isEmpty() || name.charAt(0)!='$' ; // Later scopes do not define memory
+ if( _lexSize._len > 0 )
+ for( int i=_vars.size()-1; i>=_lexSize.last(); i-- ) {
+ Var n = _vars.at(i);
+ if( n._name.equals(name) ) {
+ if( !n.isFRef() ) return false; // Double define
+ FRefNode fref = (FRefNode)in(n._idx); // Get forward ref
+ if( !xfinal || !declaredType.isConstant() ) throw fref.err(); // Must be a final constant
+ n.defFRef(declaredType,xfinal,loc); // Declare full correct type, final, source location
+ setDef(n._idx,fref.addDef(init)); // Set FRef to defined; tell parser also
+ }
+ }
+ Var v = new Var(nIns(),name,declaredType,xfinal,loc,init==Parser.XCTRL);
+ _vars.add(v);
+ // Creating a forward reference
+ if( init==Parser.XCTRL )
+ init = new FRefNode(v).init();
+ addDef(init);
+ return true;
+ }
+
+ // Read from memory
+ public Node mem( int alias ) { return mem()._mem(alias,null); }
+ // Write to memory
+ public void mem( int alias, Node st ) { mem()._mem(alias,st); }
+
+
+ /**
+ * Lookup a name in all scopes starting from most deeply nested.
+ *
+ * @param name Name to be looked up
+ * @return null if not found, or the implementing Node
+ */
+ public Var lookup( String name ) {
+ int idx = find(name);
+ // -1 is missed in all scopes, not found
+ return idx == -1 ? null : update(_vars.at(idx),null);
+ }
+
+ /**
+ * If the name is present in any scope, then redefine else null
+ *
+ * @param name Name being redefined
+ * @param n The node to bind to the name
+ */
+ public void update( String name, Node n ) {
+ int idx = find(name);
+ assert idx>=0;
+ update(_vars.at(idx),n);
+ }
+
+ public Var update( Var v, Node st ) {
+ Node old = in(v._idx);
+ if( old instanceof ScopeNode loop ) {
+ // Lazy Phi!
+ Node def = loop.in(v._idx);
+ old = def instanceof PhiNode phi && loop.ctrl()==phi.region()
+ // Loop already has a real Phi, use it
+ ? def
+ // Set real Phi in the loop head
+ // The phi takes its one input (no backedge yet) from a recursive
+ // lookup, which might have insert a Phi in every loop nest.
+ : loop.setDef(v._idx,new PhiNode(v._name, v.lazyGLB(), loop.ctrl(), loop.in(loop.update(v,null)._idx),null).peephole());
+ setDef(v._idx,old);
+ }
+ assert !v._final || st==null;
+ if( st!=null ) setDef(v._idx,st); // Set new value
+ return v;
+ }
+
+ /**
+ * Duplicate a ScopeNode; including all levels, up to Nodes. So this is
+ * neither shallow (would dup the Scope but not the internal HashMap
+ * tables), nor deep (would dup the Scope, the HashMap tables, but then
+ * also the program Nodes).
+ * <p>
+ * If the {@code loop} flag is set, the edges are filled in as the original
+ * Scope, as an indication of Lazy Phis at loop heads. The goal here is to
+ * not make Phis at loop heads for variables which are never touched in the
+ * loop body.
+ * <p>
+ * The new Scope is a full-fledged Node with proper use<->def edges.
+ */
+ public ScopeNode dup() { return dup(false); }
+ public ScopeNode dup(boolean loop) {
+ ScopeNode dup = new ScopeNode();
+ // Our goals are:
+ // 1) duplicate the name bindings of the ScopeNode across all stack levels
+ // 2) Make the new ScopeNode a user of all the nodes bound
+ // 3) Ensure that the order of defs is the same to allow easy merging
+ dup._vars .addAll(_vars );
+ dup._lexSize.addAll(_lexSize);
+ dup._kinds .addAll(_kinds );
+ dup._guards .addAll(_guards );
+ // The dup'd guards all need dup'd keepers, to keep proper accounting
+ // when later removing all guards
+ for( Node n : _guards )
+ if( !(n instanceof CFGNode) )
+ n.keep();
+ dup.addDef(ctrl()); // Control input is just copied
+
+ // Memory input is a shallow copy
+ MemMergeNode memdup = new MemMergeNode(true), mem = mem();
+ memdup.addDef(null);
+ memdup.addDef(loop ? this : mem.in(1));
+ for( int i=2; i<mem.nIns(); i++ )
+ // For lazy phis on loops we use a sentinel
+ // that will trigger phi creation on update
+ memdup.addDef(loop ? this : mem.in(i));
+ dup.addDef(memdup);
+
+ // Copy of other inputs
+ for( int i=2; i<nIns(); i++ )
+ // For lazy phis on loops we use a sentinel
+ // that will trigger phi creation on update
+ dup.addDef(loop && !_vars.at(i)._final ? this : in(i));
+ return dup;
+ }
+
+ /**
+ * Merges the names whose node bindings differ, by creating Phi node for such names
+ * The names could occur at all stack levels, but a given name can only differ in the
+ * innermost stack level where the name is bound.
+ *
+ * @param that The ScopeNode to be merged into this
+ * @return A new node representing the merge point
+ */
+ public RegionNode mergeScopes(ScopeNode that, Parser.Lexer loc) {
+ RegionNode r = ctrl(new RegionNode(loc,null,ctrl(), that.ctrl()).keep());
+ mem()._merge(that.mem(),r);
+ this ._merge(that ,r);
+ that.kill(); // Kill merged scope
+ CodeGen.CODE.add(r);
+ return r.unkeep();
+ }
+
+ private void _merge(ScopeNode that, RegionNode r) {
+ for( int i = 2; i < nIns(); i++)
+ if( in(i) != that.in(i) ) { // No need for redundant Phis
+ // If we are in lazy phi mode we need to a lookup
+ // by name as it will trigger a phi creation
+ Var v = _vars.at(i);
+ Node lhs = this.in(this.update(v,null));
+ Node rhs = that.in(that.update(v,null));
+ setDef(i, new PhiNode(v._name, v.type(), r, lhs, rhs).peephole());
+ }
+ }
+
+ // Balance arms of an IF. Extra lonely defs are thrown: "if(pred) int x;".
+ // Forward refs are copied to the other side, "as if" they were there all along.
+ public void balanceIf( ScopeNode scope ) {
+ for( int i = nIns(); i < scope.nIns(); i++ ) {
+ Var n = scope._vars.at(i);
+ if( n.isFRef() ) { // RHS has forward refs
+ _vars.add(n); // Copy to LHS
+ addDef(scope.in(i));
+ } else
+ throw Parser.error("Cannot define a '"+n._name+"' on one arm of an if",n._loc);
+ }
+ }
+
+
+ // peephole the backedge scope into this loop head scope
+ // We set the second input to the phi from the back edge (i.e. loop body)
+ public void endLoop(ScopeNode back, ScopeNode exit ) {
+ Node ctrl = ctrl();
+ assert ctrl instanceof LoopNode loop && loop.inProgress();
+ ctrl.setDef(2,back.ctrl());
+
+ mem()._endLoopMem( this, back.mem(), exit.mem() );
+ this ._endLoop ( this, back , exit );
+ back.kill(); // Loop backedge is dead
+ // Now one-time do a useless-phi removal
+ mem()._useless();
+ this ._useless();
+
+ // The exit mem's lazy default value had been the loop top,
+ // now it goes back to predating the loop.
+ exit.mem().setDef(1,mem().in(1));
+ }
+
+ // Fill in the backedge of any inserted Phis
+ void _endLoop( ScopeNode scope, Node back, Node exit ) {
+ for( int i=2; i<nIns(); i++ ) {
+ if( _vars.at(i)._final ) continue; // Final vars did not get modified in the loop
+ if( _vars.at(i).type().isHighOrConst() ) continue; // Cannot lift higher than a constant, so no Phi
+ if( back.in(i) != scope ) {
+ PhiNode phi = (PhiNode)in(i);
+ assert phi.region()==scope.ctrl() && phi.in(2)==null;
+ phi.setDef(2,back.in(i)); // Fill backedge
+ }
+ if( exit.in(i) == scope ) // Replace a lazy-phi on the exit path also
+ exit.setDef(i,in(i));
+ }
+ }
+
+
+ // Up-casting: using the results of an If to improve a value.
+ // E.g. "if( ptr ) ptr.field;" is legal because ptr is known not-null.
+ public void addGuards( Node ctrl, Node pred, boolean invert ) {
+ assert ctrl instanceof CFGNode;
+ _guards.add(ctrl); // Marker to distinguish 0,1,2 guards
+ // add pred & its cast to the normal input list, with special Vars
+ if( pred==null || pred.isDead() )
+ return; // Dead, do not add any guards
+ // Invert the If conditional
+ if( invert )
+ pred = pred instanceof NotNode not ? not.in(1) : CodeGen.CODE.add(new NotNode(pred).peephole());
+ // This is a zero/null test.
+ // Compute the positive test type.
+ Type tnz = pred._type.nonZero();
+ if( tnz!=null )
+ _addGuard(tnz,ctrl,pred);
+
+ // Compute the negative test type.
+ if( pred instanceof NotNode not ) {
+ Node npred = not.in(1);
+ Type tzero = npred._type.makeZero();
+ _addGuard(tzero,ctrl,npred);
+ }
+ }
+
+ private void _addGuard(Type guard, Node ctrl, Node pred) {
+ Type tcast = guard.join(pred._type);
+ if( tcast != pred._type && !tcast.isHigh() ) {
+ Node cast = new CastNode(tcast,ctrl,pred.keep()).peephole().keep();
+ _guards.add(pred);
+ _guards.add(cast);
+ replace(pred,cast);
+ }
+ }
+
+
+ // Remove matching pred/cast pairs from this guarded region.
+ public ScopeNode removeGuards( Node ctrl ) {
+ assert ctrl instanceof CFGNode;
+ // 0,1 or 2 guards
+ while( true ) {
+ Node g = _guards.pop();
+ if( g == ctrl ) break;
+ if( g instanceof CFGNode ) continue;
+ g .unkill(); // Pop/kill cast
+ _guards.pop().unkill(); // Pop/kill pred
+ }
+ return this;
+ }
+
+ // If we find a guarded instance of pred, replace with the upcasted version
+ public Node upcastGuard( Node pred ) {
+ // If finding an instanceof pred, replace with cast.
+ // Otherwise, just pred itself.
+ int i = _guards._len;
+ while( i > 0 ) {
+ Node cast = _guards.at(--i);
+ if( cast instanceof CFGNode ) continue; // Marker between guard sets
+ Node xpred = _guards.at(--i);
+ if( xpred == pred )
+ return cast;
+ }
+ return pred;
+ }
+
+ // Kill guards also
+ @Override public void kill() {
+ for( Node n : _guards )
+ if( !(n instanceof CFGNode) )
+ n.unkill();
+ _guards.clear();
+ // Can have lazy uses remaining
+ if( isUnused() )
+ super.kill();
+ }
+
+
+ private void replace( Node old, Node cast ) {
+ assert old!=null && old!=cast;
+ for( int i=0; i<nIns(); i++ )
+ if( in(i)==old )
+ setDef(i,cast);
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ShlNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ShlNode.java
new file mode 100644
index 00000000..21dbd503
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ShlNode.java
@@ -0,0 +1,53 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+public class ShlNode extends LogicalNode {
+ public ShlNode(Parser.Lexer loc, Node lhs, Node rhs) { super(loc, lhs, rhs); }
+
+ @Override public String label() { return "Shl"; }
+ @Override public String op() { return "<<"; }
+
+ @Override public String glabel() { return "&lt;&lt;"; }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if (t1 instanceof TypeInteger i0 &&
+ t2 instanceof TypeInteger i1 ) {
+ if( i0 == TypeInteger.ZERO )
+ return TypeInteger.ZERO;
+ if( i0.isConstant() && i1.isConstant() )
+ return TypeInteger.constant(i0.value()<<i1.value());
+ }
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+
+ if( rhs._type instanceof TypeInteger shl && shl.isConstant() ) {
+ // Shl of 0.
+ if( (shl.value()&63)==0 )
+ return lhs;
+ // (x + c) << i => (x << i) + (c << i)
+ if( lhs instanceof AddNode add && add.addDep(this).in(2)._type instanceof TypeInteger c && c.isConstant() ) {
+ long sum = c.value() << shl.value();
+ if( Integer.MIN_VALUE <= sum && sum <= Integer.MAX_VALUE )
+ return new AddNode(new ShlNode(_loc,add.in(1),rhs).peephole(), Parser.con(sum) );
+ }
+ }
+
+ // TODO: x << 3 << (y ? 1 : 2) ==> x << (y ? 4 : 5)
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new ShlNode(_loc,lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ShrNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ShrNode.java
new file mode 100644
index 00000000..789fb8a8
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ShrNode.java
@@ -0,0 +1,46 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+public class ShrNode extends LogicalNode {
+ public ShrNode(Parser.Lexer loc, Node lhs, Node rhs) { super(loc, lhs, rhs); }
+
+ @Override public String label() { return "Shr"; }
+ @Override public String op() { return ">>>"; }
+
+ @Override public String glabel() { return "&gt;&gt;&gt;"; }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if (t1 instanceof TypeInteger i0 &&
+ t2 instanceof TypeInteger i1 ) {
+ if( i0 == TypeInteger.ZERO )
+ return TypeInteger.ZERO;
+ if( i0.isConstant() && i1.isConstant() )
+ return TypeInteger.constant(i0.value()>>>i1.value());
+ }
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t2 = rhs._type;
+
+ // Shr of 0.
+ if( t2.isConstant() && t2 instanceof TypeInteger i && (i.value()&63)==0 )
+ return lhs;
+
+ // TODO: x >>> 3 >>> (y ? 1 : 2) ==> x >>> (y ? 4 : 5)
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new ShrNode(_loc,lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/StartNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/StartNode.java
new file mode 100644
index 00000000..26e08535
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/StartNode.java
@@ -0,0 +1,58 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.*;
+import java.util.Arrays;
+import java.util.BitSet;
+import java.util.HashSet;
+import static com.seaofnodes.simple.Utils.TODO;
+
+/**
+ * The Start node represents the start of the function.
+ *
+ * Start initially has 1 input (arg) from outside and the initial control.
+ * In ch10 we also add mem aliases as structs get defined; each field in struct
+ * adds a distinct alias to Start's tuple.
+ */
+public class StartNode extends LoopNode implements MultiNode {
+
+ final Type _arg;
+
+ public StartNode(Type arg) { super((Parser.Lexer)null,null); _arg = arg; _type = compute(); }
+ public StartNode(StartNode start) { super(start); _arg = start._arg; }
+
+ @Override public String label() { return "Start"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ return sb.append(label());
+ }
+
+ @Override public boolean isMultiHead() { return true; }
+ @Override public boolean blockHead() { return true; }
+ @Override public CFGNode cfg0() { return null; }
+
+ // Get the one control following; error to call with more than one e.g. an
+ // IfNode or other multi-way branch. For Start, its "main"
+ @Override public CFGNode uctrl() {
+ // Find "main", its the start.
+ CFGNode C = null;
+ for( Node use : _outputs )
+ if( use instanceof FunNode fun && fun.sig().isa(CodeGen.CODE._main) )
+ { assert C==null; C = fun; }
+ return C;
+ }
+
+
+ @Override public TypeTuple compute() {
+ return TypeTuple.make(Type.CONTROL,TypeMem.TOP,_arg);
+ }
+
+ @Override public Node idealize() { return null; }
+
+ // No immediate dominator, and idepth==0
+ @Override public int idepth() { return 0; }
+ @Override public CFGNode idom(Node dep) { return null; }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/StopNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/StopNode.java
new file mode 100644
index 00000000..6aaba3b3
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/StopNode.java
@@ -0,0 +1,64 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.type.Type;
+import java.util.BitSet;
+
+public class StopNode extends CFGNode {
+
+ public final String _src;
+
+ public StopNode(String src) {
+ super();
+ _src = src;
+ _type = compute();
+ }
+ public StopNode(StopNode stop) { super(stop); _src = stop._src; }
+
+ @Override
+ public String label() {
+ return "Stop";
+ }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ // For the sake of many old tests, and single value prints as "return val"
+ if( ret()!=null ) return ret()._print0(sb,visited);
+ sb.append("Stop[ ");
+ for( Node ret : _inputs )
+ ret._print0(sb, visited).append(" ");
+ return sb.append("]");
+ }
+
+ @Override public boolean blockHead() { return true; }
+
+
+ // If a single Return, return it.
+ // Otherwise, null because ambiguous.
+ public ReturnNode ret() {
+ return nIns()==1 && in(0) instanceof ReturnNode ret ? ret : null;
+ }
+
+ @Override
+ public Type compute() {
+ return Type.BOTTOM;
+ }
+
+ @Override
+ public Node idealize() {
+ int len = nIns();
+ for( int i=0; i<nIns(); i++ )
+ if( ((ReturnNode)in(i)).fun().isDead() )
+ delDef(i--);
+ if( len != nIns() ) return this;
+ return null;
+ }
+
+ @Override public int idepth() {
+ if( _idepth!=0 ) return _idepth;
+ int d=0;
+ for( Node ret : _inputs )
+ d = Math.max(d,((ReturnNode)ret).idepth()+1);
+ return _idepth=d;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/StoreNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/StoreNode.java
new file mode 100644
index 00000000..93294dba
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/StoreNode.java
@@ -0,0 +1,113 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+
+/**
+ * Store represents setting a value to a memory based object, in chapter 10
+ * this means a field inside a struct.
+ */
+public class StoreNode extends MemOpNode {
+
+ private final boolean _init; // Initializing writes are allowed to write null
+
+ /**
+ * @param name The struct field we are assigning to
+ * @param mem The memory alias node - this is updated after a Store
+ * @param ptr The ptr to the struct base where we will store a value
+ * @param off The offset inside the struct base
+ * @param value Value to be stored
+ */
+ public StoreNode(Parser.Lexer loc, String name, int alias, Type glb, Node mem, Node ptr, Node off, Node value, boolean init) {
+ super(loc, name, alias, glb, mem, ptr, off, value);
+ _init = init;
+ }
+
+ // GraphVis DOT code and debugger labels
+ @Override public String label() { return "st_"+mlabel(); }
+ // GraphVis node-internal labels
+ @Override public String glabel() { return "." +_name+"="; }
+ @Override public boolean isMem() { return true; }
+
+ public Node val() { return in(4); }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ return sb.append(".").append(_name).append("=").append( val()).append(";");
+ }
+
+ @Override
+ public Type compute() {
+ Type val = val()._type;
+ TypeMem mem = (TypeMem)mem()._type; // Invariant
+ if( mem == TypeMem.TOP ) return TypeMem.TOP;
+ Type t = Type.BOTTOM; // No idea on field contents
+ // Same alias, lift val to the declared type and then meet into other fields
+ if( mem._alias == _alias ) {
+ // Update declared forward ref to the actual
+ if( _declaredType.isFRef() && val instanceof TypeMemPtr tmp && !tmp.isFRef() )
+ _declaredType = tmp;
+ val = val.join(_declaredType);
+ t = val.meet(mem._t);
+ }
+ return TypeMem.make(_alias,t);
+ }
+
+ @Override
+ public Node idealize() {
+
+ // Simple store-after-store on same address. Should pick up the
+ // required init-store being stomped by a first user store.
+ if( mem() instanceof StoreNode st &&
+ ptr()==st.ptr() && // Must check same object
+ off()==st.off() && // And same offset (could be "same alias" but this handles arrays to same index)
+ ptr()._type instanceof TypeMemPtr && // No bother if weird dead pointers
+ // Must have exactly one use of "this" or you get weird
+ // non-serializable memory effects in the worse case.
+ checkOnlyUse(st) ) {
+ assert _name.equals(st._name); // Equiv class aliasing is perfect
+ setDef(1,st.mem());
+ return this;
+ }
+
+ // Value is automatically truncated by narrow store
+ if( val() instanceof AndNode and && and.in(2)._type.isConstant() ) {
+ int log = _declaredType.log_size();
+ if( log<3 ) { // And-mask vs narrow store
+ long mask = ((TypeInteger)and.in(2)._type).value();
+ long bits = (1L<<(8<<log))-1;
+ // Mask does not mask any of the stored bits
+ if( (bits&mask)==bits )
+ // So and-mask is already covered by the store
+ { setDef(4,and.in(1)); return this; }
+ }
+ }
+
+
+ return null;
+ }
+
+ // Check that "mem" has no uses except "this"
+ private boolean checkOnlyUse(Node mem) {
+ if( mem.nOuts()==1 ) return true;
+ // Add deps on the other uses (can be e.g. ScopeNode mid-parse) so that
+ // when the other uses go away we can retry.
+ for( Node use : mem._outputs )
+ if( use != this )
+ use.addDep(this);
+ return false;
+ }
+
+ @Override
+ public Parser.ParseException err() {
+ Parser.ParseException err = super.err();
+ if( err != null ) return err;
+ TypeMemPtr tmp = (TypeMemPtr)ptr()._type;
+ if( tmp._obj.field(_name)._final && !_init )
+ return Parser.error("Cannot modify final field '"+_name+"'",_loc);
+ Type t = val()._type;
+ //return _init || t.isa(_declaredType) ? null : Parser.error("Cannot store "+t+" into field "+_declaredType+" "+_name,_loc);
+ return null;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/StructNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/StructNode.java
new file mode 100644
index 00000000..076b342a
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/StructNode.java
@@ -0,0 +1,46 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.type.*;
+import java.util.BitSet;
+
+/**
+ * Build a compound object
+ */
+public class StructNode extends Node {
+
+ public TypeStruct _ts;
+
+ @Override public String label() { return _ts==null ? "STRUCT?" : _ts.str(); }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ if( _ts==null ) return sb.append("STRUCT?");
+ sb.append(_ts._name).append(" {");
+ for( int i=0; i<nIns(); i++ ) {
+ sb.append(_ts._fields[i]._fname).append(":");
+ sb.append((in(i)==null ? Type.BOTTOM : in(i)._type).print(new SB()));
+ sb.append("; ");
+ }
+ sb.setLength(sb.length()-2);
+ return sb.append("}");
+ }
+
+ @Override
+ public TypeStruct compute() {
+ if( _ts==null ) return TypeStruct.BOT;
+ Field[] fs = new Field[_ts._fields.length];
+ for( int i=0; i<fs.length; i++ )
+ fs[i] = _ts._fields[i].makeFrom(in(i)==null ? Type.TOP : in(i)._type);
+ return TypeStruct.make(_ts._name,fs);
+ }
+
+ @Override
+ public Node idealize() { return null; }
+
+ @Override
+ boolean eq(Node n) { return _ts == ((StructNode)n)._ts; }
+
+ @Override
+ int hash() { return _ts==null ? 0 : _ts.hashCode(); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/SubFNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/SubFNode.java
new file mode 100644
index 00000000..b591718d
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/SubFNode.java
@@ -0,0 +1,44 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFloat;
+
+import java.util.BitSet;
+
+public class SubFNode extends Node {
+ public SubFNode(Node lhs, Node rhs) { super(null, lhs, rhs); }
+
+ @Override public String label() { return "SubF"; }
+
+ @Override public String glabel() { return "-"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append("-"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ if (in(1)._type instanceof TypeFloat i0 &&
+ in(2)._type instanceof TypeFloat i1) {
+ if (i0.isConstant() && i1.isConstant())
+ return TypeFloat.constant(i0.value()-i1.value());
+ }
+ return in(1)._type.meet(in(2)._type);
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Type t2 = in(2)._type;
+
+ // Sub of 0.
+ if ( t2.isConstant() && t2 instanceof TypeFloat i && i.value()==0 )
+ return lhs;
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new SubFNode(lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/SubNode.java
new file mode 100644
index 00000000..339c65ca
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -0,0 +1,59 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+public class SubNode extends Node {
+ public SubNode(Node lhs, Node rhs) { super(null, lhs, rhs); }
+
+ @Override public String label() { return "Sub"; }
+
+ @Override public String glabel() { return "-"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ in(1)._print0(sb.append("("), visited);
+ in(2)._print0(sb.append("-"), visited);
+ return sb.append(")");
+ }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ // Sub of same is 0
+ if( in(1)==in(2) )
+ return TypeInteger.ZERO;
+ if( t1 instanceof TypeInteger i1 &&
+ t2 instanceof TypeInteger i2 ) {
+ if (i1.isConstant() && i2.isConstant())
+ return TypeInteger.constant(i1.value()-i2.value());
+ // Fold ranges like {2-3} - {0-1} into {1-3}.
+ if( !AddNode.overflow(i1._min,-i2._max) &&
+ !AddNode.overflow(i1._max,-i2._min) &&
+ i2._min != Long.MIN_VALUE )
+ return TypeInteger.make(i1._min-i2._max,i1._max-i2._min);
+ }
+
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ // x - (-y) is x+y
+ if( in(2) instanceof MinusNode minus )
+ return new AddNode(in(1),minus.in(1));
+
+ // (-x) - y is -(x+y)
+ if( in(1) instanceof MinusNode minus )
+ return new MinusNode(new AddNode(minus.in(1),in(2)).peephole());
+
+ return null;
+ }
+
+ @Override Node copy(Node lhs, Node rhs) { return new SubNode(lhs,rhs); }
+ @Override Node copyF() { return new SubFNode(null,null); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/ToFloatNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/ToFloatNode.java
new file mode 100644
index 00000000..1f4d67e0
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/ToFloatNode.java
@@ -0,0 +1,34 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFloat;
+import com.seaofnodes.simple.type.TypeInteger;
+
+import java.util.BitSet;
+
+public class ToFloatNode extends Node {
+ public ToFloatNode(Node lhs) { super(null, lhs); }
+
+ @Override public String label() { return "ToFloat"; }
+
+ @Override public String glabel() { return "(flt)"; }
+
+ @Override
+ StringBuilder _print1(StringBuilder sb, BitSet visited) {
+ return in(1)._print0(sb.append("(flt)"), visited);
+ }
+
+ @Override
+ public Type compute() {
+ if( in(1)._type == Type.NIL ) return TypeFloat.FZERO;
+ if (in(1)._type instanceof TypeInteger i0 ) {
+ if( i0.isHigh() ) return TypeFloat.F64.dual();
+ if( i0.isConstant() )
+ return TypeFloat.constant(i0.value());
+ }
+ return TypeFloat.F64;
+ }
+
+ @Override public Node idealize() { return null; }
+ @Override Node copy(Node lhs, Node rhs) { return new ToFloatNode(lhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/XCtrlNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/XCtrlNode.java
new file mode 100644
index 00000000..9b4245c7
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/XCtrlNode.java
@@ -0,0 +1,16 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import java.util.BitSet;
+
+public class XCtrlNode extends CFGNode {
+ public XCtrlNode() { super(new Node[]{CodeGen.CODE._start}); }
+ @Override public String label() { return "Xctrl"; }
+ @Override StringBuilder _print1(StringBuilder sb, BitSet visited) { return sb.append("Xctrl"); }
+ @Override public boolean isConst() { return true; }
+ @Override public boolean isMultiTail() { return true; }
+ @Override public Type compute() { return Type.XCONTROL; }
+ @Override public Node idealize() { return null; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/XorNode.java b/chapter20/src/main/java/com/seaofnodes/simple/node/XorNode.java
new file mode 100644
index 00000000..37d7147d
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/XorNode.java
@@ -0,0 +1,54 @@
+package com.seaofnodes.simple.node;
+
+import com.seaofnodes.simple.Parser;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.util.BitSet;
+
+public class XorNode extends LogicalNode {
+ public XorNode(Parser.Lexer loc, Node lhs, Node rhs) { super(loc, lhs, rhs); }
+
+ @Override public String label() { return "Xor"; }
+ @Override public String op() { return "^"; }
+
+ @Override public String glabel() { return "^"; }
+
+ @Override
+ public Type compute() {
+ Type t1 = in(1)._type, t2 = in(2)._type;
+ if( t1.isHigh() || t2.isHigh() )
+ return TypeInteger.TOP;
+ if( t1 instanceof TypeInteger i0 &&
+ t2 instanceof TypeInteger i1 ) {
+ if( i0.isConstant() && i1.isConstant() )
+ return TypeInteger.constant(i0.value()^i1.value());
+ }
+ return TypeInteger.BOT;
+ }
+
+ @Override
+ public Node idealize() {
+ Node lhs = in(1);
+ Node rhs = in(2);
+ Type t1 = lhs._type;
+ Type t2 = rhs._type;
+
+ // Xor of 0. We do not check for (0^x) because this will already
+ // canonicalize to (x^0)
+ if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==0 )
+ return lhs;
+
+ // Move constants to RHS: con*arg becomes arg*con
+ if ( t1.isConstant() && !t2.isConstant() )
+ return swap12();
+
+ // Do we have ((x ^ (phi cons)) ^ con) ?
+ // Do we have ((x ^ (phi cons)) ^ (phi cons)) ?
+ // Push constant up through the phi: x ^ (phi con0^con0 con1^con1...)
+ Node phicon = AddNode.phiCon(this,true);
+ if( phicon!=null ) return phicon;
+
+ return null;
+ }
+ @Override Node copy(Node lhs, Node rhs) { return new XorNode(_loc,lhs,rhs); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddFMemX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddFMemX86.java
new file mode 100644
index 00000000..4f75edcd
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddFMemX86.java
@@ -0,0 +1,33 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.node.*;
+
+public class AddFMemX86 extends MemOpX86 {
+ AddFMemX86( AddFNode add, LoadNode ld , Node base, Node idx, int off, int scale, Node val ) {
+ super(add,ld, base, idx, off, scale, 0, val );
+ }
+
+ @Override public RegMask regmap(int i) {
+ if( i==1 ) return RegMask.EMPTY; // Memory
+ if( i==2 ) return x86_64_v2.RMASK; // base
+ if( i==3 ) return x86_64_v2.RMASK; // index
+ if( i==4 ) return x86_64_v2.XMASK; // value
+ throw Utils.TODO();
+ }
+
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.XMASK; }
+
+
+ // General form: "add dst = src + [base + idx<<2 + 12]"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ");
+ sb.p(val()==null ? "#"+_imm : code.reg(val())).p(" + ");
+ asm_address(code,sb);
+ }
+ @Override public String op() { return "addf"+_sz; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddFX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddFX86.java
new file mode 100644
index 00000000..a3f5c7b3
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddFX86.java
@@ -0,0 +1,29 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class AddFX86 extends MachConcreteNode implements MachNode {
+ AddFX86( Node addf ) { super(addf); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.XMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.XMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "addf dst += src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" + ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "addf"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddIX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddIX86.java
new file mode 100644
index 00000000..6a332ff5
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddIX86.java
@@ -0,0 +1,39 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class AddIX86 extends MachConcreteNode implements MachNode {
+ final TypeInteger _ti;
+ AddIX86( Node add, TypeInteger ti ) {
+ super(add);
+ _inputs.pop();
+ _ti = ti;
+ }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) {
+ // assert i== i;
+ return x86_64_v2.WMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "addi dst += #imm"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" + #");
+ _ti.print(sb);
+ }
+
+ @Override public String op() {
+ return _ti.value() == 1 ? "inc" : (_ti.value() == -1 ? "dec" : "addi");
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddMemX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddMemX86.java
new file mode 100644
index 00000000..7d45d757
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddMemX86.java
@@ -0,0 +1,25 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.node.*;
+
+public class AddMemX86 extends MemOpX86 {
+ AddMemX86( AddNode add, LoadNode ld , Node base, Node idx, int off, int scale, int imm, Node val ) {
+ super(add,ld, base, idx, off, scale, imm, val );
+ }
+
+ @Override public String op() { return "add"+_sz; }
+
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+
+ // General form: "add dst = src + [base + idx<<2 + 12]"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ");
+ sb.p(val()==null ? "#"+_imm : code.reg(val())).p(" + ");
+ asm_address(code,sb);
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddX86.java
new file mode 100644
index 00000000..61aa5a9e
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AddX86.java
@@ -0,0 +1,29 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class AddX86 extends MachConcreteNode implements MachNode {
+ AddX86( Node add ) { super(add); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.RMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "add dst += src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" + ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "add"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AndIX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AndIX86.java
new file mode 100644
index 00000000..f2ee1c66
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/AndIX86.java
@@ -0,0 +1,42 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+import java.util.BitSet;
+import java.lang.StringBuilder;
+
+public class AndIX86 extends MachConcreteNode implements MachNode {
+ final TypeInteger _ti;
+ AndIX86(Node and, TypeInteger ti) {
+ super(and);
+ _inputs.pop();
+ _ti = ti;
+ }
+
+ // Register mask allowed on input i.
+ // This is the normal calling convention
+ @Override public RegMask regmap(int i) { assert i==1; return x86_64_v2.WMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form
+ // General form: "andi dst & #imm"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" & #");
+ _ti.print(sb);
+ }
+
+ @Override public String op() { return "andi"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CallRX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CallRX86.java
new file mode 100644
index 00000000..31d303ed
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CallRX86.java
@@ -0,0 +1,31 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFunPtr;
+import java.io.ByteArrayOutputStream;
+
+public class CallRX86 extends CallNode implements MachNode {
+ CallRX86( CallNode call ) { super(call); }
+
+ @Override public String label() { return op(); }
+ @Override public RegMask regmap(int i) {
+ return i==_inputs._len
+ ? x86_64_v2.WMASK // Function call target
+ : x86_64_v2.callInMask(i); // Normal argument
+ }
+ @Override public RegMask outregmap() { return x86_64_v2.RET_MASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(fptr()));
+ }
+
+ @Override public String op() { return "callr"; }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CallX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CallX86.java
new file mode 100644
index 00000000..9c246c24
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CallX86.java
@@ -0,0 +1,40 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFunPtr;
+import java.io.ByteArrayOutputStream;
+import java.util.BitSet;
+
+public class CallX86 extends CallNode implements MachNode {
+ final TypeFunPtr _tfp;
+ final String _name;
+ CallX86( CallNode call, TypeFunPtr tfp ) {
+ super(call);
+ _inputs.pop(); // Pop constant target
+ assert tfp.isConstant();
+ _tfp = tfp;
+ _name = CodeGen.CODE.link(tfp)._name;
+ }
+
+ @Override public String label() { return op(); }
+ @Override public RegMask regmap(int i) {
+ return x86_64_v2.callInMask(i); // Normal argument
+ }
+ @Override public RegMask outregmap() { return x86_64_v2.RET_MASK; }
+
+ @Override public String name() { return _name; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(_name);
+ }
+
+ @Override public String op() { return "call"; }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpIX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpIX86.java
new file mode 100644
index 00000000..2fa7fbb1
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpIX86.java
@@ -0,0 +1,43 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+// Compare immediate. Sets flags.
+public class CmpIX86 extends MachConcreteNode implements MachNode {
+ final int _imm;
+ final String _bop;
+ CmpIX86( BoolNode bool, TypeInteger ti ) {
+ super(bool);
+ _inputs.pop(); // Toss ideal ConstantNode away, embedded into machine op
+ _bop = bool.op(); // One of <,<=,==
+ _imm = (int)ti.value();
+ assert _imm == ti.value();
+ }
+ CmpIX86( Node cmp, double ignore ) {
+ super(cmp);
+ _bop = "==";
+ _imm = 0;
+ }
+
+ @Override public RegMask regmap(int i) { assert i==1; return x86_64_v2.RMASK; }
+ @Override public RegMask outregmap() { return x86_64_v2.FLAGS_MASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ @Override public void asm(CodeGen code, SB sb) {
+ String dst = code.reg(this);
+ if( dst!="FLAGS" ) sb.p(dst).p(" = ");
+ sb.p(code.reg(in(1)));
+ if( _imm != 0 ) sb.p(", #").p(_imm);
+ }
+
+ @Override public String op() { return _imm==0 ? "test" : "cmp"; }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpMemX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpMemX86.java
new file mode 100644
index 00000000..873ca9df
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpMemX86.java
@@ -0,0 +1,33 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.node.*;
+
+public class CmpMemX86 extends MemOpX86 {
+ final boolean _invert; // Op switched LHS, RHS
+ CmpMemX86( BoolNode bool, LoadNode ld , Node base, Node idx, int off, int scale, int imm, Node val, boolean invert ) {
+ super(bool,ld, base, idx, off, scale, imm, val );
+ _invert = invert;
+ }
+
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.FLAGS_MASK; }
+
+ // General form: "cmp dst = src, [base + idx<<2 + 12]"
+ @Override public void asm(CodeGen code, SB sb) {
+ String dst = code.reg(this);
+ if( dst!="FLAGS" ) sb.p(dst).p(" = ");
+ if( _invert ) asm_address(code,sb).p(",");
+ if( val()==null ) {
+ if( _imm!=0 ) sb.p("#").p(_imm);
+ } else {
+ sb.p(code.reg(val()));
+ }
+ if( !_invert ) asm_address(code,sb.p(", "));
+ }
+
+ @Override public String op() { return ((val()==null && _imm==0) ? "test" : "cmp") + _sz; }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpX86.java
new file mode 100644
index 00000000..6b502249
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/CmpX86.java
@@ -0,0 +1,27 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class CmpX86 extends MachConcreteNode implements MachNode {
+ CmpX86( Node cmp ) { super(cmp); }
+
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.RMASK; }
+ @Override public RegMask outregmap() { return x86_64_v2.FLAGS_MASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "add dst += src"
+ @Override public void asm(CodeGen code, SB sb) {
+ String dst = code.reg(this);
+ if( dst!="FLAGS" ) sb.p(dst).p(" = ");
+ sb.p(code.reg(in(1))).p(", ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "cmp"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/DivFX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/DivFX86.java
new file mode 100644
index 00000000..d73bfd5b
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/DivFX86.java
@@ -0,0 +1,33 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class DivFX86 extends MachConcreteNode implements MachNode {
+ DivFX86( Node divf) { super(divf); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.XMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.XMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+
+ // General form: "divf dst /= src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" / ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() {
+ // 8 bytes = 64 bits
+ return "divf";
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/DivX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/DivX86.java
new file mode 100644
index 00000000..1dc20017
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/DivX86.java
@@ -0,0 +1,31 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class DivX86 extends MachConcreteNode implements MachNode {
+ DivX86( Node div ) { super(div); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) {
+ assert i==1 || i==2;
+ return x86_64_v2.RMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "div dst /= src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" / ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "div"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/FltX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/FltX86.java
new file mode 100644
index 00000000..21529f7b
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/FltX86.java
@@ -0,0 +1,36 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.node.ConstantNode;
+import com.seaofnodes.simple.node.MachNode;
+
+import java.io.ByteArrayOutputStream;
+
+public class FltX86 extends ConstantNode implements MachNode {
+ FltX86(ConstantNode con ) { super(con); }
+
+ // Register mask allowed on input i. 0 for no register.
+ @Override public RegMask regmap(int i) { return RegMask.EMPTY; }
+ // General int registers
+ @Override public RegMask outregmap() { return x86_64_v2.XMASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // Human-readable form appended to the SB. Things like the encoding,
+ // indentation, leading address or block labels not printed here.
+ // Just something like "ld4\tR17=[R18+12] // Load array base".
+ // General form: "op\tdst=src+src"
+ @Override public void asm(CodeGen code, SB sb) {
+ _con.print(sb.p(code.reg(this)).p(" #"));
+ }
+
+ @Override public String op() {
+ return "fld"; // Some fancier encoding
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/FunX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/FunX86.java
new file mode 100644
index 00000000..f969fae4
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/FunX86.java
@@ -0,0 +1,21 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.node.FunNode;
+import com.seaofnodes.simple.node.MachNode;
+import java.io.ByteArrayOutputStream;
+
+public class FunX86 extends FunNode implements MachNode {
+ FunX86( FunNode fun ) { super(fun); }
+
+ // Register mask allowed on input i. 0 for no register.
+ @Override public RegMask regmap(int i) { return RegMask.EMPTY; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return RegMask.EMPTY; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/I2f8X86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/I2f8X86.java
new file mode 100644
index 00000000..983f817d
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/I2f8X86.java
@@ -0,0 +1,28 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class I2f8X86 extends MachConcreteNode implements MachNode {
+ I2f8X86(Node i2f8 ) { super(i2f8); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1; return x86_64_v2.WMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.XMASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "i2f8 (flt)int_value"
+
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p("(flt)").p(code.reg(in(1)));
+ }
+
+ @Override public String op() { return "i2f8"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/IntX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/IntX86.java
new file mode 100644
index 00000000..2cd27c14
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/IntX86.java
@@ -0,0 +1,45 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.ConstantNode;
+import com.seaofnodes.simple.node.MachNode;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+
+import java.io.ByteArrayOutputStream;
+
+// Integer constants
+public class IntX86 extends ConstantNode implements MachNode {
+
+ IntX86( ConstantNode con ) {
+ super(con);
+ }
+
+ // Register mask allowed on input i. 0 for no register.
+ @Override public RegMask regmap(int i) { return RegMask.EMPTY; }
+ // General int registers
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // Human-readable form appended to the SB. Things like the encoding,
+ // indentation, leading address or block labels not printed here.
+ // Just something like "ld4\tR17=[R18+12] // Load array base".
+ // General form: "op\tdst=src+src"
+ @Override public void asm(CodeGen code, SB sb) {
+ String reg = code.reg(this);
+ if( _con == Type.NIL || _con == TypeInteger.ZERO )
+ sb.p(reg).p(",").p(reg);
+ else
+ _con.print(sb.p(reg).p(" #"));
+ }
+
+ @Override public String op() {
+ if( _con == Type.NIL || _con == TypeInteger.ZERO )
+ return "xor";
+ return "ldi"; // Some fancier encoding
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/JmpX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/JmpX86.java
new file mode 100644
index 00000000..7cf4444c
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/JmpX86.java
@@ -0,0 +1,46 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+// Jump on flags, uses flags
+public class JmpX86 extends IfNode implements MachNode {
+ final String _bop;
+ JmpX86( IfNode iff, String bop ) {
+ super(iff);
+ _bop = bop;
+ }
+
+ @Override public String label() { return op(); }
+
+ @Override public void postSelect() {
+ Node set = in(1);
+ Node cmp = set.in(1);
+ // Bypass an expected Set and just reference the cmp directly
+ if( set instanceof SetX86 && (cmp instanceof CmpX86 || cmp instanceof CmpIX86 || cmp instanceof CmpMemX86) )
+ _inputs.set(1,cmp);
+ else
+ throw Utils.TODO();
+ }
+ @Override public RegMask regmap(int i) { assert i==1; return x86_64_v2.FLAGS_MASK; }
+ @Override public RegMask outregmap() { return RegMask.EMPTY; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ @Override public void asm(CodeGen code, SB sb) {
+ String src = code.reg(in(1));
+ if( src!="FLAGS" ) sb.p(src);
+ }
+
+ @Override public String op() { return "j"+_bop; }
+
+ @Override public String comment() {
+ return "L"+cproj(1)._nid+", L"+cproj(0)._nid;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/LeaX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/LeaX86.java
new file mode 100644
index 00000000..a49b8d7f
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/LeaX86.java
@@ -0,0 +1,42 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class LeaX86 extends MachConcreteNode implements MachNode {
+ final int _scale;
+ final long _offset;
+ LeaX86( Node add, Node base, Node idx, int scale, long offset ) {
+ super(add);
+ assert scale==1 || scale==2 || scale==4 || scale==8;
+ _inputs.pop();
+ _inputs.pop();
+ _inputs.push(base);
+ _inputs.push(idx);
+ _scale = scale;
+ _offset = offset;
+ }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.RMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "lea dst = base + 4*idx + 12"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ");
+ if( in(1) != null )
+ sb.p(code.reg(in(1))).p(" + ");
+ sb.p(code.reg(in(2))).p("*").p(_scale);
+ if( _offset!=0 ) sb.p(" + #").p(_offset);
+ }
+
+ @Override public String op() { return "lea"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/LoadX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/LoadX86.java
new file mode 100644
index 00000000..02a9a4fe
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/LoadX86.java
@@ -0,0 +1,25 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.node.LoadNode;
+import com.seaofnodes.simple.node.Node;
+
+public class LoadX86 extends MemOpX86 {
+ LoadX86( LoadNode ld, Node base, Node idx, int off, int scale ) {
+ super(ld,ld, base, idx, off, scale, 0);
+ }
+
+ @Override public String op() { return "ld"+_sz; }
+
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+
+ // General form: "ldN dst,[base + idx<<2 + 12]"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(",");
+ asm_address(code,sb);
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MemAddX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MemAddX86.java
new file mode 100644
index 00000000..418f63f3
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MemAddX86.java
@@ -0,0 +1,28 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.node.*;
+
+public class MemAddX86 extends MemOpX86 {
+ MemAddX86( StoreNode st, Node base, Node idx, int off, int scale, int imm, Node val ) {
+ super(st, st, base, idx, off, scale, imm, val );
+ }
+
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return RegMask.EMPTY; }
+
+
+ // General form: "add [base + idx<<2 + 12] += src"
+ @Override public void asm(CodeGen code, SB sb) {
+ asm_address(code,sb);
+ if( val()==null ) {
+ if( _imm != 1 && _imm != -1 ) sb.p(" += #").p(_imm);
+ } else sb.p(" += ").p(code.reg(val()));
+ }
+
+ @Override public String op() {
+ return (_imm == 1 ? "inc" : (_imm == -1 ? "dec" : "add")) + _sz;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MemOpX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MemOpX86.java
new file mode 100644
index 00000000..1e678a0b
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MemOpX86.java
@@ -0,0 +1,87 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.*;
+import java.io.ByteArrayOutputStream;
+import java.lang.StringBuilder;
+import java.util.BitSet;
+
+// Generic X86 memory operand base.
+// inputs:
+// ctrl - will appear for possibly RCE (i.e. array ops)
+// mem - memory dependence edge
+// base - Basic object pointer
+// idx/null - Scaled index offset, or null if none
+// val/null - Value to store, as part of a op-to-mem or op-from-mem. Null for loads, or if an immediate is being used
+// Constants:
+// offset - offset added to base. Can be zero.
+// scale - scale on index; only 0,1,2,4,8 allowed, 0 is only when index is null
+// imm - immediate value to store or op-to-mem, and only when val is null
+public abstract class MemOpX86 extends MemOpNode implements MachNode {
+ final int _off; // Limit 32 bits
+ final int _scale; // Limit 0,1,2,3
+ final int _imm; // Limit 32 bits
+ final char _sz = (char)('0'+(1<<_declaredType.log_size()));
+ MemOpX86( Node op, MemOpNode mop, Node base, Node idx, int off, int scale, int imm ) {
+ super(op,mop);
+ assert base._type instanceof TypeMemPtr && !(base instanceof AddNode);
+ assert (idx==null && scale==0) || (idx!=null && 0<= scale && scale<=3);
+
+ // Copy memory parts from eg the LoadNode over the opcode, e.g. an Add
+ if( op != mop ) {
+ _inputs.set(0,mop.in(0)); // Control from mem op
+ _inputs.set(1,mop.in(1)); // Memory from mem op
+ _inputs.set(2,base); // Base handed in
+ }
+
+ assert ptr() == base;
+ _inputs.setX(3,idx);
+ _off = off;
+ _scale = scale;
+ _imm = imm;
+ }
+
+ // Store-based flavors have a value edge
+ MemOpX86( Node op, MemOpNode mop, Node base, Node idx, int off, int scale, int imm, Node val ) {
+ this(op,mop,base,idx,off,scale,imm);
+ _inputs.setX(4,val);
+ }
+
+ Node idx() { return in(3); }
+ Node val() { return in(4); }
+
+ @Override public StringBuilder _printMach(StringBuilder sb, BitSet visited) { return sb.append(".").append(_name); }
+
+ @Override public String label() { return op(); }
+ @Override public Type compute() { throw Utils.TODO(); }
+ @Override public Node idealize() { throw Utils.TODO(); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) {
+ if( i==1 ) return RegMask.EMPTY; // Memory
+ if( i==2 ) return x86_64_v2.RMASK; // base
+ if( i==3 ) return x86_64_v2.RMASK; // index
+ if( i==4 ) return x86_64_v2.RMASK; // value
+ throw Utils.TODO();
+ }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { throw Utils.TODO(); }
+
+ @Override public int encoding(ByteArrayOutputStream bytes) { throw Utils.TODO(); }
+
+
+ // "[base + idx<<2 + 12]"
+ SB asm_address(CodeGen code, SB sb) {
+ sb.p("[").p(code.reg(ptr()));
+ if( idx() != null ) {
+ sb.p("+").p(code.reg(idx()));
+ if( _scale != 0 )
+ sb.p("<<").p(_scale);
+ }
+ if( _off != 0 )
+ sb.p("+").p(_off);
+ return sb.p("]");
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulFX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulFX86.java
new file mode 100644
index 00000000..aef813e1
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulFX86.java
@@ -0,0 +1,30 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeFloat;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class MulFX86 extends MachConcreteNode implements MachNode {
+ MulFX86( Node mulf) { super(mulf); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.XMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.XMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "mulf dst *= src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" * ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "mulf"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulIX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulIX86.java
new file mode 100644
index 00000000..7508cf4c
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulIX86.java
@@ -0,0 +1,36 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class MulIX86 extends MachConcreteNode implements MachNode {
+ final TypeInteger _ti;
+ MulIX86(Node mul, TypeInteger ti) {super(mul); _inputs.pop(); _ti = ti;}
+
+ // Register mask allowed on input i.
+ // This is the normal calling convention
+ @Override public RegMask regmap(int i) {
+ // assert i==1;
+ return x86_64_v2.WMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+ // General form
+ // General form: "muli dst * #imm"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" * #");
+ _ti.print(sb);
+ }
+
+ @Override public String op() { return "muli"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulX86.java
new file mode 100644
index 00000000..15fd9496
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/MulX86.java
@@ -0,0 +1,30 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class MulX86 extends MachConcreteNode implements MachNode {
+
+ MulX86( Node mul ) { super(mul); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.RMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "mul dst *= src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" * ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "mul"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/NewX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/NewX86.java
new file mode 100644
index 00000000..4396a917
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/NewX86.java
@@ -0,0 +1,40 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import java.io.ByteArrayOutputStream;
+
+public class NewX86 extends NewNode implements MachNode {
+
+ // A pre-zeroed chunk of memory.
+ NewX86( NewNode nnn ) { super(nnn); }
+
+ // Register mask allowed on input i, the size
+ @Override public RegMask regmap(int i) {
+ // Size
+ if( i==1 ) return x86_64_v2.RDI_MASK;
+ // All the memory alias edges
+ return RegMask.EMPTY;
+ }
+ @Override public RegMask outregmap() { throw Utils.TODO(); }
+
+ // Register mask allowed as a result. Pointer result in standard calling
+ // convention.
+ @Override public RegMask outregmap(int i) {
+ if( i == 1 ) return x86_64_v2.RET_MASK;
+ // All the memory aliases edges
+ return RegMask.EMPTY;
+ }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "alloc #bytes"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(size()));
+ }
+
+ @Override public String op() { return "alloc"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/OrIX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/OrIX86.java
new file mode 100644
index 00000000..513962c2
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/OrIX86.java
@@ -0,0 +1,44 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.node.MachConcreteNode;
+import com.seaofnodes.simple.node.MachNode;
+import com.seaofnodes.simple.node.Node;
+import com.seaofnodes.simple.type.TypeInteger;
+
+import java.io.ByteArrayOutputStream;
+
+public class OrIX86 extends MachConcreteNode implements MachNode {
+
+ final TypeInteger _ti;
+ OrIX86(Node or, TypeInteger ti) {super(or); _inputs.pop(); _ti = ti;}
+
+ // Register mask allowed on input i.
+ // This is the normal calling convention
+ @Override public RegMask regmap(int i) {
+ //assert i==1;
+ return x86_64_v2.WMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form
+ // General form: "ori ori | #imm"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" | #");
+ _ti.print(sb);
+ }
+
+ @Override public String op() { return "ori"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ParmX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ParmX86.java
new file mode 100644
index 00000000..8a439644
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ParmX86.java
@@ -0,0 +1,24 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.node.ParmNode;
+import com.seaofnodes.simple.node.MachNode;
+import java.io.ByteArrayOutputStream;
+
+public class ParmX86 extends ParmNode implements MachNode {
+ final RegMask _rmask;
+ ParmX86( ParmNode parm ) {
+ super(parm);
+ _rmask = x86_64_v2.callInMask(_idx);
+ }
+
+ // Register mask allowed on input i. 0 for no register.
+ @Override public RegMask regmap(int i) { return RegMask.EMPTY; }
+ // Register mask allowed as a result. Calling convention register
+ @Override public RegMask outregmap() { return _rmask; }
+
+ // Encoding is appended into the byte array. Returns size
+ @Override public int encoding(ByteArrayOutputStream bytes) { return 0; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ProjX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ProjX86.java
new file mode 100644
index 00000000..2849b232
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ProjX86.java
@@ -0,0 +1,23 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.node.ProjNode;
+import com.seaofnodes.simple.node.MachNode;
+import java.io.ByteArrayOutputStream;
+
+public class ProjX86 extends ProjNode implements MachNode {
+
+ ProjX86( ProjNode p ) { super(p); }
+
+ // Register mask allowed on input i. 0 for no register.
+ @Override public RegMask regmap(int i) { return RegMask.EMPTY; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return RegMask.EMPTY; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/RetX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/RetX86.java
new file mode 100644
index 00000000..e6219ff4
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/RetX86.java
@@ -0,0 +1,48 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.FunNode;
+import com.seaofnodes.simple.node.ReturnNode;
+import com.seaofnodes.simple.node.MachNode;
+import java.io.ByteArrayOutputStream;
+
+// Return
+public class RetX86 extends ReturnNode implements MachNode {
+ RetX86( ReturnNode ret, FunNode fun ) { super(ret, fun); fun.setRet(this); }
+
+ // Correct Nodes outside the normal edges
+ @Override public void postSelect() {
+ FunNode fun = (FunNode)rpc().in(0);
+ _fun = fun;
+ fun.setRet(this);
+ }
+
+ // Register mask allowed on input i.
+ // This is the normal calling convention
+ @Override public RegMask regmap(int i) {
+ return switch( i ) {
+ case 0 -> RegMask.EMPTY;
+ case 1 -> RegMask.EMPTY;
+ case 2 -> x86_64_v2.RET_MASK;
+ case 3 -> RegMask.EMPTY; // RPC is always on stack
+ default -> throw Utils.TODO();
+ };
+ }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return RegMask.EMPTY; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // Human-readable form appended to the SB. Things like the encoding,
+ // indentation, leading address or block labels not printed here.
+ // Just something like "ld4\tR17=[R18+12] // Load array base".
+ // General form: "op\tdst=src+src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "ret"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SarX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SarX86.java
new file mode 100644
index 00000000..3d907eef
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SarX86.java
@@ -0,0 +1,40 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+import java.util.BitSet;
+import java.lang.StringBuilder;
+
+
+public class SarX86 extends MachConcreteNode implements MachNode {
+ final TypeInteger _ti;
+ SarX86(Node sar, TypeInteger ti) {super(sar); _inputs.pop(); _ti = ti;}
+
+ // Register mask allowed on input i.
+ // This is the normal calling convention
+ @Override public RegMask regmap(int i) {
+ // assert i==1;
+ return x86_64_v2.RMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form
+ // General form: "sari dst << #imm"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" >> #");
+ _ti.print(sb);
+ }
+
+ @Override public String op() { return "sari"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SetX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SetX86.java
new file mode 100644
index 00000000..25367e03
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SetX86.java
@@ -0,0 +1,39 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+// Compare immediate. Sets flags.
+// Corresponds to the x86 instruction "sete && setne".
+// Use result of comparison without jump.
+public class SetX86 extends MachConcreteNode implements MachNode {
+ final String _bop; // One of <,<=,==
+ // Constructor expects input is an X86 and not an Ideal node.
+ SetX86( Node cmp, String bop ) {
+ super(cmp);
+ _inputs.setLen(1); // Pop the cmp inputs
+ // Replace with the matched cmp
+ _inputs.push(cmp);
+ _bop = bop;
+ }
+
+ @Override public RegMask regmap(int i) { assert i==1; return x86_64_v2.FLAGS_MASK; }
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this));
+ String src = code.reg(in(1));
+ if( src!="FLAGS" ) sb.p(" = ").p(src);
+ }
+
+ @Override public String op() { return "set"+_bop; }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ShlIX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ShlIX86.java
new file mode 100644
index 00000000..61e0d262
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ShlIX86.java
@@ -0,0 +1,38 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+import java.util.BitSet;
+
+public class ShlIX86 extends MachConcreteNode implements MachNode{
+ final TypeInteger _ti;
+ ShlIX86(Node shl, TypeInteger ti) {super(shl); _inputs.pop(); _ti = ti;}
+
+ // Register mask allowed on input i.
+ // This is the normal calling convention
+ @Override public RegMask regmap(int i) {
+ //assert i==1;
+ return x86_64_v2.RMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form
+ // General form: "shli dst << #imm"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" << #");
+ _ti.print(sb);
+ }
+
+ @Override public String op() { return "shli"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ShrIX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ShrIX86.java
new file mode 100644
index 00000000..08cae93e
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/ShrIX86.java
@@ -0,0 +1,39 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+import java.util.BitSet;
+import java.lang.StringBuilder;
+
+public class ShrIX86 extends MachConcreteNode implements MachNode{
+ final TypeInteger _ti;
+ ShrIX86(Node shr, TypeInteger ti) {super(shr); _inputs.pop(); _ti = ti;}
+
+ // Register mask allowed on input i.
+ // This is the normal calling convention
+ @Override public RegMask regmap(int i) {
+ //assert i==1;
+ return x86_64_v2.RMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form
+ // General form: "shri dst >>> #imm"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" >>> #");
+ _ti.print(sb);
+ }
+
+ @Override public String op() { return "shri"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/StoreX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/StoreX86.java
new file mode 100644
index 00000000..c9191b87
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/StoreX86.java
@@ -0,0 +1,30 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.node.Node;
+import com.seaofnodes.simple.node.StoreNode;
+import java.util.BitSet;
+
+public class StoreX86 extends MemOpX86 {
+ StoreX86( StoreNode st, Node base, Node idx, int off, int scale, int imm, Node val ) {
+ super(st,st, base, idx, off, scale, imm, val);
+ }
+
+ @Override public String op() { return "st"+_sz; }
+
+ @Override public StringBuilder _printMach(StringBuilder sb, BitSet visited) {
+ return sb.append(".").append(_name).append("=").append(val()==null ? _imm : val()).append(";");
+ }
+
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return RegMask.EMPTY; }
+
+ // General form: "stN [base + idx<<2 + 12],val"
+ @Override public void asm(CodeGen code, SB sb) {
+ asm_address(code,sb).p(",");
+ if( val()==null ) sb.p("#").p(_imm);
+ else sb.p(code.reg(val()));
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SubFX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SubFX86.java
new file mode 100644
index 00000000..ed19ad79
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SubFX86.java
@@ -0,0 +1,29 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import java.io.ByteArrayOutputStream;
+
+public class SubFX86 extends MachConcreteNode implements MachNode {
+ SubFX86( Node subf) { super(subf); }
+
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.XMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.XMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "subf dst -= src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" - ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "subf"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SubX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SubX86.java
new file mode 100644
index 00000000..cac59d3b
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/SubX86.java
@@ -0,0 +1,29 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import java.io.ByteArrayOutputStream;
+
+public class SubX86 extends MachConcreteNode implements MachNode {
+ SubX86( Node sub ) { super(sub); }
+
+ // Register mask allowed on input i.
+ @Override public RegMask regmap(int i) { assert i==1 || i==2; return x86_64_v2.RMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form: "sub dst -= src"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" - ").p(code.reg(in(2)));
+ }
+
+ @Override public String op() { return "sub"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/TFPX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/TFPX86.java
new file mode 100644
index 00000000..bd88011f
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/TFPX86.java
@@ -0,0 +1,41 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.*;
+import com.seaofnodes.simple.node.ConstantNode;
+import com.seaofnodes.simple.node.MachNode;
+import com.seaofnodes.simple.type.Type;
+import com.seaofnodes.simple.type.TypeFunPtr;
+
+import java.io.ByteArrayOutputStream;
+
+// Function constants
+public class TFPX86 extends ConstantNode implements MachNode {
+ TFPX86( ConstantNode con ) { super(con); }
+ // Register mask allowed on input i. 0 for no register.
+ @Override public RegMask regmap(int i) { return RegMask.EMPTY; }
+ // General int registers
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // Human-readable form appended to the SB. Things like the encoding,
+ // indentation, leading address or block labels not printed here.
+ // Just something like "ld4\tR17=[R18+12] // Load array base".
+ // General form: "op\tdst=src+src"
+ @Override public void asm(CodeGen code, SB sb) {
+ String reg = code.reg(this);
+ if( _con == Type.NIL )
+ sb.p(reg).p(",").p(reg);
+ else
+ _con.print(sb.p(reg).p(" #"));
+ }
+
+ @Override public String op() {
+ if( _con == Type.NIL )
+ return "xor";
+ return "ldx"; // Some fancier encoding
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/XorIX86.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/XorIX86.java
new file mode 100644
index 00000000..795fa814
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/XorIX86.java
@@ -0,0 +1,42 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.node.MachConcreteNode;
+import com.seaofnodes.simple.node.MachNode;
+import com.seaofnodes.simple.node.Node;
+import com.seaofnodes.simple.type.TypeInteger;
+
+import java.io.ByteArrayOutputStream;
+
+public class XorIX86 extends MachConcreteNode implements MachNode {
+
+ final TypeInteger _ti;
+ XorIX86(Node xor, TypeInteger ti) {super(xor); _inputs.pop(); _ti = ti;}
+
+ // Register mask allowed on input i.
+ // This is the normal calling convention
+ @Override public RegMask regmap(int i) { assert i==1; return x86_64_v2.WMASK; }
+ // Register mask allowed as a result. 0 for no register.
+ @Override public RegMask outregmap() { return x86_64_v2.WMASK; }
+
+
+ // Output is same register as input#1
+ @Override public int twoAddress() { return 1; }
+
+ // Encoding is appended into the byte array; size is returned
+ @Override public int encoding(ByteArrayOutputStream bytes) {
+ throw Utils.TODO();
+ }
+
+ // General form
+ // General form: "ori xori ^ #imm"
+ @Override public void asm(CodeGen code, SB sb) {
+ sb.p(code.reg(this)).p(" = ").p(code.reg(in(1))).p(" ^ #");
+ _ti.print(sb);
+ }
+
+ @Override public String op() { return "xori"; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/x86_64_v2.java b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/x86_64_v2.java
new file mode 100644
index 00000000..45ae19dc
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/node/cpus/x86_64_v2/x86_64_v2.java
@@ -0,0 +1,418 @@
+package com.seaofnodes.simple.node.cpus.x86_64_v2;
+
+import com.seaofnodes.simple.CodeGen;
+import com.seaofnodes.simple.Machine;
+import com.seaofnodes.simple.RegMask;
+import com.seaofnodes.simple.Utils;
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.*;
+
+public class x86_64_v2 extends Machine {
+ // X86-64 V2. Includes e.g. SSE4.2 and POPCNT.
+ @Override public String name() { return "x86_64_v2"; }
+
+ public static int RAX = 0, RCX = 1, RDX = 2, RBX = 3, RSP = 4, RBP = 5, RSI = 6, RDI = 7;
+ public static int R08 = 8, R09 = 9, R10 = 10, R11 = 11, R12 = 12, R13 = 13, R14 = 14, R15 = 15;
+ public static int FLAGS = 32;
+
+ public static int XMM0 = 16, XMM1 = 17, XMM2 = 18, XMM3 = 19, XMM4 = 20, XMM5 = 21, XMM6 = 22, XMM7 = 23;
+ public static int XMM8 = 24, XMM9 = 25, XMM10 = 26, XMM11 = 27, XMM12 = 28, XMM13 = 29, XMM14 = 30, XMM15 = 31;
+
+ // General purpose register mask: pointers and ints, not floats
+ public static RegMask RMASK = new RegMask(0b1111111111111111);
+ // No RSP in the *write* general set.
+ public static RegMask WMASK = new RegMask(0b1111111111101111);
+ // Xmm register mask
+ public static RegMask XMASK = new RegMask( 0b1111111111111111L << XMM0);
+
+ public static RegMask FLAGS_MASK = new RegMask(1L<<FLAGS);
+
+ // Return single int/ptr register
+ public static RegMask RET_MASK = new RegMask(RAX);
+
+ public static RegMask RDI_MASK = new RegMask(1L<<RDI);
+ public static RegMask RCX_MASK = new RegMask(1L<<RCX);
+ public static RegMask RDX_MASK = new RegMask(1L<<RDX);
+ public static RegMask R08_MASK = new RegMask(1L<<R08);
+ public static RegMask R09_MASK = new RegMask(1L<<R09);
+ public static RegMask RSI_MASK = new RegMask(1L<<RSI);
+
+ // Calling conv metadata
+ public int GPR_COUNT_CONV_WIN64 = 4; // RCX, RDX, R9, R9
+ public int XMM_COUNT_CONV_WIN64 = 4; // XMM0L, XMM1L, XMM2L, XMM3L
+
+ public int GPR_COUNT_CONV_SYSTEM_V = 6; // RDI, RSI, RDX, RCX, R8, R9
+ public int XMM_COUNT_CONV_SYSTEM_V = 4; // XMM0, XMM1, XMM2, XMM3 ....
+ // Human-readable name for a register number, e.g. "RAX".
+ // Hard crash for bad register number, fix yer bugs!
+ public static final String[] REGS = new String[] {
+ "rax" , "rcx" , "rdx" , "rbx" , "rsp" , "rbp" , "rsi" , "rdi" ,
+ "r8" , "r9" , "r10" , "r11" , "r12" , "r13" , "r14" , "r15" ,
+ "xmm0", "xmm1", "xmm2" , "xmm3" , "xmm4" , "xmm5" , "xmm6" , "xmm7" ,
+ "xmm8", "xmm9", "xmm10", "xmm11", "xmm12", "xmm13", "xmm14", "xmm15",
+ };
+ @Override public String reg( int reg ) { return REGS[reg]; }
+
+ // Calling convention; returns a machine-specific register
+ // for incoming argument idx.
+ // index 0 for control, 1 for memory, real args start at index 2
+ static int callInArg( int idx ) {
+ return switch( CodeGen.CODE._callingConv ) {
+ case CodeGen.CallingConv.SystemV -> callInArgSystemV(idx);
+ case CodeGen.CallingConv.Win64 -> callInArgWin64 (idx);
+ };
+ }
+
+ // WIN64(param passing)
+ static RegMask[] CALLINMASK_WIN64 = new RegMask[] {
+ RegMask.EMPTY,
+ RegMask.EMPTY,
+ RCX_MASK,
+ RDX_MASK,
+ R08_MASK,
+ R09_MASK,
+ RegMask.EMPTY,
+ RegMask.EMPTY
+ };
+ static int[] CALLINARG_WIN64 = new int[] {
+ 0, // Control, no register
+ 0, // Memory, no register
+ RCX, //
+ RDX,
+ R08,
+ R09,
+ 0,
+ 0,
+ };
+ static int callInArgWin64( int idx ) { return CALLINARG_WIN64[idx]; }
+
+ // caller saved(win64)
+ public static final long WIN64_ABI_CALLER_SAVED =
+ (1L << RAX) | (1L << RCX) | (1L << RDX) | (1L << R08) | (1L << R09) | (1L << R10) | (1L << R11);
+
+ // callee saved(win64)
+ public static final long WIN64_ABI_CALLEE_SAVED = ~WIN64_ABI_CALLER_SAVED;
+
+ // SystemV(param passing)
+ static RegMask[] CALLINMASK_SYSTEMV = new RegMask[] {
+ RegMask.EMPTY,
+ RegMask.EMPTY,
+ RDI_MASK,
+ RSI_MASK,
+ RDX_MASK,
+ RCX_MASK,
+ R08_MASK,
+ R09_MASK
+ };
+ static int[] CALLINARG_SYSTEMV = new int[] {
+ 0, // Control, no register
+ 0, // Memory, no register
+ RDI,
+ RSI,
+ RDX,
+ RCX,
+ R08,
+ R09,
+ };
+ static int callInArgSystemV( int idx ) { return CALLINARG_SYSTEMV[idx]; }
+
+ // caller saved(systemv)
+ // caller saved(win64)
+ public static final long SYSTEMV_ABI_CALLER_SAVED =
+ (1L << RAX) | (1L << RDI) | (1L << RSI) | (1L << RCX) | (1L << RDX) | (1L << R08) | (1L << R09) << (1L << R10) << (1L << R11);
+ // callee saved(systemv)
+ public static final long SYSTEMV_ABI_CALLE_SAVED = ~SYSTEMV_ABI_CALLER_SAVED;
+
+
+ static RegMask callInMask( int idx ) {
+ return switch( CodeGen.CODE._callingConv ) {
+ case CodeGen.CallingConv.SystemV -> CALLINMASK_SYSTEMV[idx];
+ case CodeGen.CallingConv.Win64 -> CALLINMASK_WIN64 [idx];
+ };
+ }
+
+ // Create a split op; any register to any register, including stack slots
+ @Override public Node split() {
+ throw Utils.TODO();
+ }
+
+ // Return a MachNode unconditional branch
+ @Override public CFGNode jump() {
+ throw Utils.TODO();
+ }
+
+ // Break an infinite loop
+ @Override public IfNode never( CFGNode ctrl ) {
+ throw Utils.TODO();
+ }
+
+ // Instruction selection
+ @Override public Node instSelect( Node n ) {
+ return switch( n ) {
+ case AddFNode addf -> addf(addf);
+ case AddNode add -> add(add);
+ case AndNode and -> and(and);
+ case BoolNode bool -> cmp(bool);
+ case CallEndNode cend -> new CallEndNode((CallNode)cend.in(0));
+ case CallNode call -> call(call);
+ case CProjNode c -> new CProjNode(c);
+ case ConstantNode con -> con(con);
+ case DivFNode divf -> new DivFX86(divf);
+ case DivNode div -> new DivX86(div);
+ case FunNode fun -> new FunX86(fun);
+ case IfNode iff -> jmp(iff);
+ case LoadNode ld -> ld(ld);
+ case MemMergeNode mem -> new MemMergeNode(mem);
+ case MulFNode mulf -> new MulFX86(mulf);
+ case MulNode mul -> mul(mul);
+ case NewNode nnn -> new NewX86(nnn);
+ case OrNode or -> or(or);
+ case ParmNode parm -> new ParmX86(parm);
+ case PhiNode phi -> new PhiNode(phi);
+ case ProjNode prj -> prj(prj);
+ case ReadOnlyNode read -> new ReadOnlyNode(read);
+ case ReturnNode ret -> new RetX86(ret,ret.fun());
+ case SarNode sar -> sar(sar);
+ case ShlNode shl -> shl(shl);
+ case ShrNode shr -> shr(shr);
+ case StartNode start -> new StartNode(start);
+ case StopNode stop -> new StopNode(stop);
+ case StoreNode st -> st(st);
+ case SubFNode subf -> new SubFX86(subf);
+ case SubNode sub -> sub(sub);
+ case ToFloatNode tfn -> i2f8(tfn);
+ case XorNode xor -> xor(xor);
+
+ case LoopNode loop -> new LoopNode(loop);
+ case RegionNode region-> new RegionNode(region);
+ default -> throw Utils.TODO();
+ };
+ }
+
+
+ // Attempt a full LEA-style break down.
+ private Node add( AddNode add ) {
+ Node lhs = add.in(1);
+ Node rhs = add.in(2);
+ if( lhs instanceof LoadNode ld && ld.nOuts()==1 )
+ return new AddMemX86(add,address(ld),ld.ptr(),idx,off,scale, imm(rhs),val);
+
+ if( rhs instanceof LoadNode ld && ld.nOuts()==1 )
+ throw Utils.TODO(); // Swap load sides
+
+ // Attempt a full LEA-style break down.
+ // Returns one of AddX86, AddIX86, LeaX86, or LHS
+ if( rhs instanceof ConstantNode off && off._con instanceof TypeInteger toff ) {
+ if( lhs instanceof AddNode ladd )
+ // ((base + (idx << scale)) + off)
+ return _lea(add,ladd.in(1),ladd.in(2),toff.value());
+ if( lhs instanceof ShlNode shift )
+ // (idx << scale) + off; no base
+ return _lea(add,null,shift,toff.value());
+
+ // lhs + rhs1
+ if( toff.value()==0 ) return add;
+ return new AddIX86(add, toff);
+ }
+ return _lea(add,lhs,rhs,0);
+ }
+
+
+ private Node addf( AddFNode addf ) {
+ if( addf.in(1) instanceof LoadNode ld && ld.nOuts()==1 )
+ return new AddFMemX86(addf,address(ld),ld.ptr(),idx,off,scale, addf.in(2));
+
+ if( addf.in(2) instanceof LoadNode ld && ld.nOuts()==1 )
+ throw Utils.TODO(); // Swap load sides
+
+ return new AddFX86(addf);
+ }
+
+
+ private Node _lea( Node add, Node base, Node idx, long off ) {
+ int scale = 1;
+ if( base instanceof ShlNode && !(idx instanceof ShlNode) ) throw Utils.TODO(); // Bug in canonicalization, should on RHS
+ if( idx instanceof ShlNode shift && shift.in(2) instanceof ConstantNode shfcon &&
+ shfcon._con instanceof TypeInteger tscale && 0 <= tscale.value() && tscale.value() <= 3 ) {
+ idx = shift.in(1);
+ scale = 1 << ((int)tscale.value());
+ }
+ // (base + idx) + off
+ return off==0 && scale==1
+ ? new AddX86(add)
+ : new LeaX86(add,base,idx,scale,off);
+ }
+
+
+ private Node and(AndNode and) {
+ if( and.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti )
+ return new AndIX86(and, ti);
+ throw Utils.TODO();
+ }
+
+ private Node call(CallNode call) {
+ if( call.fptr() instanceof ConstantNode con && con._con instanceof TypeFunPtr tfp )
+ return new CallX86(call, tfp);
+ return new CallRX86( call );
+ }
+
+ // Because X86 flags, a normal ideal Bool is 2 X86 ops: a "cmp" and at "setz".
+ // Ideal If reading from a setz will skip it and use the "cmp" instead.
+ private Node cmp( BoolNode bool ) {
+ Node cmp = _cmp(bool);
+ return new SetX86(cmp,bool.op());
+ }
+ private Node _cmp( BoolNode bool ) {
+ Node lhs = bool.in(1);
+ Node rhs = bool.in(2);
+ if( lhs instanceof LoadNode ld && ld.nOuts()==1 )
+ return new CmpMemX86(bool,address(ld),ld.ptr(),idx,off,scale, imm(rhs),val,false);
+
+ if( rhs instanceof LoadNode ld && ld.nOuts()==1 )
+ return new CmpMemX86(bool,address(ld),ld.ptr(),idx,off,scale, imm(lhs),val,true);
+
+ return rhs instanceof ConstantNode con && con._con instanceof TypeInteger ti
+ ? new CmpIX86(bool, ti)
+ : new CmpX86(bool);
+ }
+
+ private Node con( ConstantNode con ) {
+ return switch( con._con ) {
+ case TypeInteger ti -> new IntX86(con);
+ case TypeFloat tf -> new FltX86(con);
+ case TypeFunPtr tfp -> new TFPX86(con);
+ case TypeMemPtr tmp -> new ConstantNode(con);
+ case TypeNil tn -> throw Utils.TODO();
+ // TOP, BOTTOM, XCtrl, Ctrl, etc. Never any executable code.
+ case Type t -> new ConstantNode(con);
+ };
+ }
+
+ private Node i2f8(ToFloatNode tfn) {
+ assert tfn.in(1)._type instanceof TypeInteger ti;
+ return new I2f8X86(tfn);
+ }
+
+ private Node jmp( IfNode iff ) {
+ // If/Bool combos will match to a Cmp/Set which sets flags.
+ // Most general arith ops will also set flags, which the Jmp needs directly.
+ // Loads do not set the flags, and will need an explicit TEST
+ if( !(iff.in(1) instanceof BoolNode) )
+ iff.setDef(1,new BoolNode.EQ(iff.in(1),new ConstantNode(TypeInteger.ZERO)));
+ return new JmpX86(iff, ((BoolNode)iff.in(1)).op());
+ }
+
+ private Node ld( LoadNode ld ) {
+ return new LoadX86(address(ld),ld.ptr(),idx,off,scale);
+ }
+
+ private Node mul(MulNode mul) {
+ return mul.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti
+ ? new MulIX86(mul, ti)
+ : new MulX86(mul);
+ }
+
+ private Node or(OrNode or) {
+ if( or.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti)
+ return new OrIX86(or, ti);
+ throw Utils.TODO();
+ }
+
+ private Node prj( ProjNode prj ) {
+ return new ProjX86(prj);
+ }
+
+ private Node sar( SarNode sar ) {
+ if( sar.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti)
+ return new SarX86(sar, ti);
+ throw Utils.TODO();
+ }
+
+ private Node shl( ShlNode shl ) {
+ if( shl.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti )
+ return new ShlIX86(shl, ti);
+ throw Utils.TODO();
+ }
+
+ private Node shr(ShrNode shr) {
+ if( shr.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti )
+ return new ShrIX86(shr, ti);
+ throw Utils.TODO();
+ }
+
+ private Node st( StoreNode st ) {
+ // Look for "*ptr op= val"
+ Node op = st.val();
+ if( op instanceof AddNode ) {
+ if( op.in(1) instanceof LoadNode ld &&
+ ld.in(0)==st.in(0) &&
+ ld.mem()==st.mem() &&
+ ld.ptr()==st.ptr() &&
+ ld.off()==st.off() ) {
+ if( op instanceof AddNode ) {
+ return new MemAddX86(address(st),st.ptr(),idx,off,scale,imm(op.in(2)),val);
+ }
+ throw Utils.TODO();
+ }
+ }
+
+ return new StoreX86(address(st),st.ptr(),idx,off,scale,imm(st.val()),val);
+ }
+
+ private Node sub( SubNode sub ) {
+ return sub.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti
+ ? new AddIX86(sub, TypeInteger.constant(-ti.value()))
+ : new SubX86(sub);
+ }
+
+ private Node xor(XorNode xor) {
+ if(xor.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti)
+ return new XorIX86(xor, ti);
+ throw Utils.TODO();
+ }
+
+
+ // Gather X86 addressing mode bits prior to constructing. This is a
+ // builder pattern, but saving the bits in a *local* *global* here to keep
+ // mess contained.
+ private static int off, scale, imm;
+ private static Node idx, val;
+ private <N extends MemOpNode> N address( N mop ) {
+ off = scale = imm = 0; // Reset
+ idx = val = null;
+ Node base = mop.ptr();
+ // Skip/throw-away a ReadOnly, only used to typecheck
+ if( base instanceof ReadOnlyNode read ) base = read.in(1);
+ assert !(base instanceof AddNode) && base._type instanceof TypeMemPtr; // Base ptr always, not some derived
+ if( mop.off() instanceof AddNode add && add.in(2) instanceof ConstantNode con && con._con instanceof TypeInteger ti ) {
+ off = (int)ti.value();
+ assert off == ti.value(); // In 32-bit range
+ idx = add.in(1);
+ if( idx instanceof ShlNode shift && shift.in(2) instanceof ConstantNode shfcon &&
+ shfcon._con instanceof TypeInteger tscale && 0 <= tscale.value() && tscale.value() <= 3 ) {
+ idx = shift.in(1);
+ scale = (int)tscale.value();
+ }
+ } else {
+ if( mop.off() instanceof ConstantNode con && con._con instanceof TypeInteger ti ) {
+ off = (int)ti.value();
+ assert off == ti.value(); // In 32-bit range
+ } else {
+ idx = mop.off();
+ }
+ }
+ return mop;
+ }
+ private int imm( Node xval ) {
+ assert val==null && imm==0;
+ if( xval instanceof ConstantNode con && con._con instanceof TypeInteger ti ) {
+ val = null;
+ imm = (int)ti.value();
+ assert imm == ti.value(); // In 32-bit range
+ } else {
+ val = xval;
+ }
+ return imm;
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/Field.java b/chapter20/src/main/java/com/seaofnodes/simple/type/Field.java
new file mode 100644
index 00000000..ffa9d2a6
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/Field.java
@@ -0,0 +1,74 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+
+/**
+ * Represents a field in a struct. This is not a Type in the type system.
+ */
+public class Field extends Type {
+
+ // The pair {fieldName,type} uniquely identifies a field.
+
+ // Field name
+ public final String _fname;
+ // Type of the field
+ public final Type _type;
+ // Unique memory alias, not sensibly part of a "type" but very convenient here.
+ public final int _alias;
+ // Field must be written to exactly once, no more, no less
+ public final boolean _final;
+
+ private Field(String fname, Type type, int alias, boolean xfinal ) {
+ super(TFLD);
+ _fname = fname;
+ _type = type;
+ _alias = alias;
+ _final = xfinal;
+ }
+ // Make with existing alias
+ public static Field make( String fname, Type type, int alias, boolean xfinal ) {
+ return new Field(fname,type,alias,xfinal).intern();
+ }
+ public Field makeFrom( Type type ) {
+ return type == _type ? this : new Field(_fname,type,_alias,_final).intern();
+ }
+ @Override public Field makeRO() { return _final ? this : make(_fname,_type.makeRO(),_alias,true); }
+ @Override public boolean isFinal() { return _final && _type.isFinal(); }
+
+ public static final Field TEST = make("test",Type.NIL,-2,false);
+ public static final Field TEST2= make("test",Type.NIL,-2,true);
+ public static void gather(ArrayList<Type> ts) { ts.add(TEST); ts.add(TEST2); }
+
+ @Override Field xmeet( Type that ) {
+ Field fld = (Field)that; // Invariant
+ assert _fname.equals(fld._fname);
+ assert _alias==fld._alias;
+ return make(_fname,_type.meet(fld._type),_alias,_final | fld._final);
+ }
+
+ @Override
+ public Field dual() { return make(_fname,_type.dual(),_alias,!_final); }
+
+ @Override public Field glb() {
+ Type glb = _type.glb();
+ return (glb==_type && _final) ? this : make(_fname,glb,_alias,true);
+ }
+
+ // Override in subclasses
+ int hash() { return _fname.hashCode() ^ _type.hashCode() ^ _alias ^ (_final ? 1024 : 0); }
+
+ boolean eq(Type t) {
+ Field f = (Field)t;
+ return _fname.equals(f._fname) && _type==f._type && _alias==f._alias && _final==f._final;
+ }
+
+
+ @Override
+ public SB print( SB sb ) {
+ return _type.print(sb.p(_final?"":"!").p(_fname).p(":").p(_alias).p(" : "));
+ }
+
+ @Override public String str() { return _fname; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/Type.java b/chapter20/src/main/java/com/seaofnodes/simple/type/Type.java
new file mode 100644
index 00000000..847235dd
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/Type.java
@@ -0,0 +1,235 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+import java.util.HashMap;
+
+/**
+ * These types are part of a Monotone Analysis Framework,
+ * @see <a href="https://www.cse.psu.edu/~gxt29/teaching/cse597s21/slides/08monotoneFramework.pdf">see for example this set of slides</a>.
+ * <p>
+ * The types form a lattice; @see <a href="https://en.wikipedia.org/wiki/Lattice_(order)">a symmetric complete bounded (ranked) lattice.</a>
+ * <p>
+ * This wild lattice theory will be needed later to allow us to easily beef up
+ * the analysis and optimization of the Simple compiler... but we don't need it
+ * now, just know that it is coming along in a later Chapter.
+ * <p>g
+ * One of the fun things here is that while the theory is deep and subtle, the
+ * actual implementation is darn near trivial and is generally really obvious
+ * what we're doing with it. Right now, it's just simple integer math to do
+ * simple constant folding e.g. 1+2 == 3 stuff.
+ */
+
+public class Type {
+ static final HashMap<Type,Type> INTERN = new HashMap<>();
+
+ // ----------------------------------------------------------
+ // Simple types are implemented fully here. "Simple" means: the code and
+ // type hierarchy are simple, not that the Type is conceptually simple.
+ static final byte TBOT = 0; // Bottom (ALL)
+ static final byte TTOP = 1; // Top (ANY)
+ static final byte TCTRL = 2; // Ctrl flow bottom
+ static final byte TXCTRL = 3; // Ctrl flow top (mini-lattice: any-xctrl-ctrl-all)
+ static final byte TNIL = 4; // low null of all flavors
+ static final byte TXNIL = 5; // high or choice null
+ static final byte TSIMPLE = 6; // End of the Simple Types
+
+ static final byte TPTR = 7; // All nil-able scalar values
+ static final byte TINT = 8; // All Integers; see TypeInteger
+ static final byte TFLT = 9; // All Floats ; see TypeFloat
+ static final byte TMEMPTR =10; // Memory pointer to a struct type
+ static final byte TFUNPTR =11; // Function pointer; unique signature and code address (just a bit)
+ static final byte TTUPLE =12; // Tuples; finite collections of unrelated Types, kept in parallel
+ static final byte TMEM =13; // All memory (alias 0) or A slice of memory - with specific alias
+ static final byte TSTRUCT =14; // Structs; tuples with named fields
+ static final byte TFLD =15; // Named fields in structs
+ static final byte TRPC =16; // Return Program Control (Return PC or RPC)
+
+ public final byte _type;
+
+ public boolean is_simple() { return _type < TSIMPLE; }
+ private static final String[] STRS = new String[]{"Bot","Top","Ctrl","~Ctrl","null","~nil"};
+ protected Type(byte type) { _type = type; }
+
+ public static final Type BOTTOM = new Type( TBOT ).intern(); // ALL
+ public static final Type TOP = new Type( TTOP ).intern(); // ANY
+ public static final Type CONTROL = new Type( TCTRL ).intern(); // Ctrl
+ public static final Type XCONTROL = new Type( TXCTRL ).intern(); // ~Ctrl
+ public static final Type NIL = new Type( TNIL ).intern(); // low null of all flavors
+ public static final Type XNIL = new Type( TXNIL ).intern(); // high or choice null
+ public static Type[] gather() {
+ ArrayList<Type> ts = new ArrayList<>();
+ ts.add(BOTTOM);
+ ts.add(CONTROL);
+ ts.add(NIL);
+ ts.add(XNIL);
+ TypeNil.gather(ts);
+ TypePtr.gather(ts);
+ TypeInteger.gather(ts);
+ TypeFloat.gather(ts);
+ TypeMemPtr.gather(ts);
+ TypeFunPtr.gather(ts);
+ TypeMem.gather(ts);
+ Field.gather(ts);
+ TypeStruct.gather(ts);
+ TypeTuple.gather(ts);
+ TypeRPC.gather(ts);
+ int sz = ts.size();
+ for( int i = 0; i < sz; i++ )
+ ts.add(ts.get(i).dual());
+ return ts.toArray(new Type[ts.size()]);
+ }
+
+ // Is high or on the lattice centerline.
+ public boolean isHigh () { return _type==TTOP || _type==TXCTRL || _type==TXNIL; }
+ public boolean isHighOrConst() { return isHigh() || isConstant(); }
+
+ // Strict constant values, things on the lattice centerline.
+ // Excludes both high and low values
+ public boolean isConstant() { return _type==TNIL; }
+
+ // ----------------------------------------------------------
+
+ // Notes on Type interning: At the moment it is not easy to reset the
+ // interned types because we hold static references to several types and
+ // these are scattered around. This means the INTERN cache will retain all
+ // types from every run of the Parser. For this to work correctly types
+ // must be rigorous about defining when they are the same. Also types need
+ // to be immutable once defined. The rationale for interning is
+ // *correctness* with cyclic type definitions. Simple structural recursive
+ // checks go exponential with merely sharing, but with cycles they will
+ // stack overflow and crash. Interning means we do not need to have sharing
+ // checks with every type compare, only during interning.
+
+ // Factory method which interns "this"
+ public <T extends Type> T intern() {
+ T nnn = (T)INTERN.get(this);
+ if( nnn==null )
+ INTERN.put(nnn=(T)this,this);
+ return nnn;
+ }
+
+ private int _hash; // Hash cache; not-zero when set.
+ @Override
+ public final int hashCode() {
+ if( _hash!=0 ) return _hash;
+ _hash = hash();
+ if( _hash==0 ) _hash = 0xDEADBEEF; // Bad hash from subclass; use some junk thing
+ return _hash;
+ }
+ // Override in subclasses
+ int hash() { return _type; }
+
+ @Override
+ public final boolean equals( Object o ) {
+ if( o==this ) return true;
+ if( !(o instanceof Type t)) return false;
+ if( _type != t._type ) return false;
+ return eq(t);
+ }
+ // Overridden in subclasses; subclass can assume "this!=t" and java classes are same
+ boolean eq(Type t) { return true; }
+
+
+ // ----------------------------------------------------------
+ public final Type meet(Type t) {
+ // Shortcut for the self case
+ if( t == this ) return this;
+ // Same-type is always safe in the subclasses
+ if( _type==t._type ) return xmeet(t);
+ // TypeNil vs TypeNil meet
+ if( this instanceof TypeNil ptr0 && t instanceof TypeNil ptr1 )
+ return ptr0.nmeet(ptr1);
+ // Reverse; xmeet 2nd arg is never "is_simple" and never equal to "this".
+ if( is_simple() ) return this.xmeet(t );
+ if( t.is_simple() ) return t .xmeet(this);
+ return Type.BOTTOM; // Mixing 2 unrelated types
+ }
+
+ // Compute meet right now. Overridden in subclasses.
+ // Handle cases where 'this.is_simple()' and unequal to 't'.
+ // Subclassed xmeet calls can assert that '!t.is_simple()'.
+ Type xmeet(Type t) {
+ assert is_simple(); // Should be overridden in subclass
+ // ANY meet anything is thing; thing meet ALL is ALL
+ if( _type==TBOT || t._type==TTOP ) return this;
+ if( _type==TTOP || t._type==TBOT ) return t;
+
+ // RHS TypeNil vs NIL/XNIL
+ if( _type== TNIL ) return t instanceof TypeNil ptr ? ptr.meet0() : (t._type==TXNIL ? TypePtr.PTR : BOTTOM);
+ if( _type== TXNIL ) return t instanceof TypeNil ptr ? ptr.meetX() : (t._type== TNIL ? TypePtr.PTR : BOTTOM);
+ // 'this' is only {TCTRL,TXCTRL}
+ // Other non-simple RHS things bottom out
+ if( !t.is_simple() ) return BOTTOM;
+ // If RHS is NIL/XNIL
+ if( t._type==TNIL || t._type==TXNIL ) return BOTTOM;
+ // Both are {TCTRL,TXCTRL} and unequal to each other
+ return _type==TCTRL || t._type==TCTRL ? CONTROL : XCONTROL;
+ }
+
+ public Type dual() {
+ return switch( _type ) {
+ case TBOT -> TOP;
+ case TTOP -> BOTTOM;
+ case TCTRL ->XCONTROL;
+ case TXCTRL-> CONTROL;
+ case TNIL ->XNIL;
+ case TXNIL -> NIL;
+ default -> throw Utils.TODO(); // Should not reach here
+ };
+ }
+
+ // ----------------------------------------------------------
+ // Our lattice is defined with a MEET and a DUAL.
+ // JOIN is dual of meet of both duals.
+ public final Type join(Type t) {
+ if( this==t ) return this;
+ return dual().meet(t.dual()).dual();
+ }
+
+ // True if this "isa" t; e.g. 17 isa TypeInteger.BOT
+ public boolean isa( Type t ) { return meet(t)==t; }
+
+ // True if this "isa" t up to named structures
+ public boolean shallowISA( Type t ) { return isa(t); }
+
+ public Type nonZero() { return TypePtr.NPTR; }
+
+ // Make a zero version of this type, 0 for integers and null for pointers.
+ public Type makeZero() { return Type.NIL; }
+
+ /** Compute greatest lower bound in the lattice */
+ public Type glb() { return Type.BOTTOM; }
+
+ // Is forward-reference
+ public boolean isFRef() { return false; }
+
+ // All reachable struct Fields are final
+ public boolean isFinal() { return true; }
+
+ // Make all reachable struct Fields final
+ public Type makeRO() { return this; }
+
+ // ----------------------------------------------------------
+
+ // Size in bits to hold an instance of this type.
+ // Sizes are expected to be between 1 and 64 bits.
+ // Size 0 means this either takes no space (such as a known-zero field)
+ // or isn't a scalar to be stored in memory.
+ public int log_size() { throw Utils.TODO(); }
+
+ // ----------------------------------------------------------
+ // Useful in the debugger, which calls toString everywhere.
+ // This is a more verbose dev-friendly print.
+ @Override
+ public final String toString() {
+ return print(new SB()).toString();
+ }
+
+ public SB print(SB sb) { return sb.p(str()); }
+ public SB gprint(SB sb) { return print(sb); }
+
+ // This is used by error messages, and is a shorted print.
+ public String str() { return STRS[_type]; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeFloat.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeFloat.java
new file mode 100644
index 00000000..aa205149
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeFloat.java
@@ -0,0 +1,95 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+
+/**
+ * Float Type
+ */
+public class TypeFloat extends Type {
+
+ public final static TypeFloat ONE = constant(1.0);
+ public final static TypeFloat FZERO = constant(0.0);
+ public final static TypeFloat F32 = make(32, 0);
+ public final static TypeFloat F64 = make(64, 0);
+
+ // - high -64, high -32, con 0, low +32, low +64
+ public final byte _sz;
+
+ /**
+ * The constant value or 0
+ */
+ public final double _con;
+
+ private TypeFloat(byte sz, double con) {
+ super(TFLT);
+ _sz = sz;
+ _con = con;
+ }
+ private static TypeFloat make(int sz, double con) {
+ return new TypeFloat((byte)sz,con).intern();
+ }
+
+ public static TypeFloat constant(double con) { return make(0, con); }
+
+ public static void gather(ArrayList<Type> ts) { ts.add(F64); ts.add(F32); ts.add(constant(3.141592653589793)); }
+
+ @Override public String str() {
+ return switch( _sz ) {
+ case -64 -> "~flt";
+ case -32 -> "~f32";
+ case 0 -> ""+_con+((float)_con==_con ? "f" : "");
+ case 32 -> "f32";
+ case 64 -> "flt";
+ default -> throw Utils.TODO();
+ };
+ }
+ private boolean isF32() { return ((float)_con)==_con; }
+
+ @Override public boolean isHigh () { return _sz< 0; }
+ @Override public boolean isConstant() { return _sz==0; }
+ @Override public int log_size() { return _sz==32 || _sz==-32 ? 2 : 3; }
+
+ public double value() { return _con; }
+
+ @Override
+ public TypeFloat xmeet(Type other) {
+ TypeFloat f = (TypeFloat)other;
+ // Invariant from caller: 'this' != 'other' and same class (TypeFloat).
+ TypeFloat i = (TypeFloat)other; // Contract
+ // Larger size in i1, smaller in i0
+ TypeFloat i0 = _sz < i._sz ? this : i;
+ TypeFloat i1 = _sz < i._sz ? i : this;
+
+ if( i1._sz== 64 ) return F64;
+ if( i0._sz==-64 ) return i1;
+ if( i1._sz== 32 )
+ return i0._sz==0 && !i0.isF32() ? F64 : F32;
+ if( i1._sz!= 0 ) return i1;
+ // i1 is a constant
+ if( i0._sz==-32 )
+ return i1.isF32() ? i1 : F64;
+ // Since both are constants, and are never equals (contract) unequals
+ // constants fall to bottom
+ return i0.isF32() && i1.isF32() ? F32 : F64;
+ }
+
+ @Override
+ public Type dual() {
+ return isConstant() ? this : make(-_sz,0); // Constants are a self-dual
+ }
+
+ @Override public Type makeZero() { return FZERO; }
+ @Override public Type glb() { return F64; }
+
+ @Override
+ int hash() { return (int)(Double.hashCode(_con) ^ _sz ^ (1<<17)); }
+ @Override
+ public boolean eq( Type t ) {
+ TypeFloat i = (TypeFloat)t; // Contract
+ // Allow NaN to check for equality
+ return _sz==i._sz && Double.doubleToLongBits(_con)==Double.doubleToLongBits(i._con);
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeFunPtr.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeFunPtr.java
new file mode 100644
index 00000000..be801c85
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeFunPtr.java
@@ -0,0 +1,104 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+import java.util.HashMap;
+
+/**
+ * Represents a Pointer to a function.
+ * <p></p>
+ * Functions have argument types and a return type, making a function
+ * signature. Within a signature there can be many instances of functions, and
+ * each function is labeled with a small integer constant. A TFP can represent
+ * a single signature and a set of functions; the set might contain only 1
+ * function or the zeroth function (the null ptr).
+ * <p></p>
+ * Functions with different signatures cannot be mixed, and will result in a
+ * bottom function type, which can only be null-checked.
+ */
+public class TypeFunPtr extends TypeNil {
+ // A TypeFunPtr is Signature and a set of functions.
+ public final TypeTuple _sig;
+ public final Type _ret;
+ // Cheesy easy implementation for a small set; 1 bit per unique function
+ // within the TypeTuple. Can be upgraded to a BitSet for larger classes of
+ // functions. Negative means "these 63 concrete bits plus infinite unknown more"
+ public final long _fidxs; // 63 unique functions per signature
+
+ private TypeFunPtr(byte nil, TypeTuple sig, Type ret, long fidxs) {
+ super(TFUNPTR,nil);
+ assert sig != null;
+ _sig = sig;
+ _ret = ret;
+ _fidxs = fidxs;
+ }
+
+ public static TypeFunPtr make( byte nil, TypeTuple sig, Type ret, long fidxs ) { return new TypeFunPtr(nil,sig,ret,fidxs).intern(); }
+ public static TypeFunPtr make( boolean nil, TypeTuple sig, Type ret ) { return make((byte)(nil ? 3 : 2),sig,ret,-1); }
+ @Override TypeFunPtr makeFrom( byte nil ) { return nil ==_nil ? this : make( nil,_sig,_ret, _fidxs); }
+ public TypeFunPtr makeFrom( Type ret ) { return ret ==_ret ? this : make( _nil,_sig, ret, _fidxs); }
+ public TypeFunPtr makeFrom( int fidx ) { return make((byte)2, _sig,_ret,1L<<fidx ); }
+
+ public static TypeFunPtr BOT = make((byte)3,TypeTuple.BOT,Type.BOTTOM,-1);
+ public static TypeFunPtr TEST = make((byte)2,TypeTuple.TEST,TypeInteger.BOT,1);
+ public static TypeFunPtr TEST0 = make((byte)3,TypeTuple.TEST,TypeInteger.BOT,3);
+ public static void gather(ArrayList<Type> ts) { ts.add(TEST); ts.add(TEST0); ts.add(BOT); }
+
+ @Override
+ Type xmeet(Type t) {
+ TypeFunPtr that = (TypeFunPtr) t;
+ return TypeFunPtr.make(xmeet0(that),(TypeTuple)_sig.meet(that._sig), _ret.meet(that._ret), _fidxs | that._fidxs);
+ }
+
+ @Override
+ public TypeFunPtr dual() { return TypeFunPtr.make(dual0(), _sig.dual(), _ret.dual(), ~_fidxs); }
+
+ // RHS is NIL; do not deep-dual when crossing the centerline
+ @Override public Type meet0() { return _nil==3 ? this : make((byte)3,_sig,_ret,_fidxs); }
+
+ @Override public TypeFunPtr glb() { return make((byte)3,_sig,_ret,-1L); }
+
+ @Override public boolean isHigh () { return _nil <= 1 || (_nil==2 && _fidxs==0); }
+ @Override public boolean isConstant() { return (_nil==2 && Long.bitCount(_fidxs)==1) || (_nil==3 && _fidxs==0); }
+
+ @Override public int log_size() { return 2; } // (1<<2)==4-byte pointers
+
+ public Type arg(int i) { return _sig._types[i]; }
+ public long fidxs() { return _fidxs; }
+ public Type ret() { return _ret; }
+ public int nargs() { return _sig._types.length; }
+
+ @Override
+ int hash() { return Utils.fold(_sig.hashCode() ^ _ret.hashCode() ^ _fidxs ^ super.hash()); }
+
+ @Override
+ boolean eq(Type t) {
+ TypeFunPtr ptr = (TypeFunPtr)t; // Invariant
+ return _sig == ptr._sig && _ret == ptr._ret && _fidxs == ptr._fidxs && super.eq(ptr);
+ }
+
+ @Override public String str() { return print(new SB()).toString(); }
+ @Override public SB print(SB sb) { return _print(sb,false,true); }
+ public SB print(SB sb, boolean n) { return _print(sb,false,n); }
+ @Override public SB gprint(SB sb) { return _print(sb,true ,true); }
+ private static SB _print(SB sb, boolean g, Type t) { return g ? t.gprint(sb) : t.print(sb); }
+ private SB _print(SB sb, boolean g, boolean n) {
+ sb.p(x()).p("{ ");
+ if( _sig._types!=null )
+ for( Type t : _sig._types )
+ _print(sb,g,t).p(" ");
+ _print(sb.p(g ? "&rarr; " : "-> "),g,_ret).p(" #");
+ if( isHigh() ) sb.p("~");
+ long fidxs = isHigh() ? ~_fidxs : _fidxs;
+ String fidx = fidxs==0 ? ""
+ : Long.bitCount(fidxs) == 1 ? ""+Long.numberOfTrailingZeros(fidxs)
+ : fidxs == -1 ? "ALL"
+ : "b"+Long.toBinaryString(fidxs); // Just some function bits
+ return sb.p(fidx).p("}").p(q());
+ }
+
+ // Usage: for( long fidxs=fidxs(); fidxs!=0; fidxs=nextFIDX(fidxs) { int fidxs = Long.numberOfTrailingZeros(fidxs); ... }
+ public static long nextFIDX(long fidxs) { return fidxs & (fidxs-1); }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeInteger.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeInteger.java
new file mode 100644
index 00000000..cccb85a5
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeInteger.java
@@ -0,0 +1,128 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+
+/**
+ * Integer Type
+ */
+public class TypeInteger extends Type {
+
+ public final static TypeInteger ZERO= make(0,0);
+ public final static TypeInteger FALSE=ZERO;
+ public final static TypeInteger TRUE= make(1,1);
+
+ public final static TypeInteger I1 = make(-1,0);
+ public final static TypeInteger I8 = make(-128,127);
+ public final static TypeInteger I16 = make(-32768,32767);
+ public final static TypeInteger I32 = make(-1L<<31,(1L<<31)-1);
+ public final static TypeInteger BOT = make(Long.MIN_VALUE,Long.MAX_VALUE);
+ public final static TypeInteger TOP = BOT.dual();
+
+ public final static TypeInteger U1 = make(0,1);
+ public final static TypeInteger BOOL= U1;
+ public final static TypeInteger U8 = make(0,255);
+ public final static TypeInteger U16 = make(0,65535);
+ public final static TypeInteger U32 = make(0,(1L<<32)-1);
+
+ /**
+ * Describes an integer *range* - everything from min to max; both min and
+ * max are inclusive. If min==max, this is a constant.
+ * <br>
+ * If min <= max, this is a below center (towards bottom).
+ * If min > max, this is an above center (towards top).
+ */
+ public final long _min, _max;
+
+ private TypeInteger(long min, long max) {
+ super(TINT);
+ _min = min;
+ _max = max;
+ }
+
+ // Strict non-zero contract
+ public static TypeInteger make(long lo, long hi) { return new TypeInteger(lo,hi).intern(); }
+
+ public static TypeInteger constant(long con) { return make(con, con); }
+
+ public static void gather(ArrayList<Type> ts) { ts.add(I32); ts.add(BOT); ts.add(U1); ts.add(I1); ts.add(U8); }
+
+ @Override public String str() {
+ if( isConstant() ) return ""+_min;
+ long lo = _min, hi = _max;
+ String x = "";
+ if( hi < lo ) {
+ lo = _max; hi = _min;
+ x = "~";
+ }
+ return x+_str(lo,hi);
+ }
+ private static String _str(long lo, long hi) {
+ if( lo==Long.MIN_VALUE && hi==Long.MAX_VALUE ) return "int";
+ if( lo== 0 && hi== 1 ) return "bool";
+ if( lo== -1 && hi== 0 ) return "i1";
+ if( lo== -128 && hi== 127 ) return "i8";
+ if( lo== -32768 && hi== 32767 ) return "i16";
+ if( lo== -1L<<31 && hi==(1L<<31)-1 ) return "i32";
+ if( lo== 0 && hi== 255 ) return "u8";
+ if( lo== 0 && hi== 65535 ) return "u16";
+ if( lo== 0 && hi==(1L<<32)-1 ) return "u32";
+ return "["+lo+"-"+hi+"]";
+ }
+
+ @Override public boolean isHigh () { return _min > _max; }
+ @Override public boolean isConstant() { return _min == _max; }
+
+ @Override public int log_size() {
+ if( this==I8 || this==U8 || this==BOOL ) return 0; // 1<<0 == 1 bytes
+ if( this==I16 || this==U16 ) return 1; // 1<<1 == 2 bytes
+ if( this==I32 || this==U32 ) return 2; // 1<<2 == 4 bytes
+ if( this==BOT ) return 3; // 1<<3 == 8 bytes
+ if( isHighOrConst() ) return 0;
+ throw Utils.TODO();
+ }
+
+ public long value() { assert isConstant(); return _min; }
+
+ // AND-mask of forced zeros. e.g. unsigned types will return their mask;
+ // u8 will return 0xFF. But also a range of 16-18 (0x10-0x12) will return
+ // 0x13 - no value in the range {16,17,18} will allow bit 0x04 to be set.
+ public long mask() {
+ if( isHigh() ) return 0;
+ if( isConstant() ) return _min;
+ // Those bit positions which differ min to max
+ long x = _min ^ _max;
+ // Highest '1' bit in the differ set. Since the range is from min to
+ // max, all values below here are possible.
+ long ff1 = Long.highestOneBit(x);
+ // Make a all-1's mask from ff1, and set over the same bits (either min
+ // or max is ok).
+ long mask = _min | (ff1-1) | ff1;
+ return mask;
+ }
+
+ @Override
+ public Type xmeet(Type other) {
+ // Invariant from caller: 'this' != 'other' and same class (TypeInteger)
+ TypeInteger i = (TypeInteger)other; // Contract
+ return make(Math.min(_min,i._min), Math.max(_max,i._max));
+ }
+
+ @Override public TypeInteger dual() { return make(_max,_min); }
+
+ @Override public TypeInteger nonZero() {
+ if( isHigh() ) return this;
+ if( this==ZERO ) return null; // No sane answer
+ if( _min==0 ) return make(1,Math.max(_max,1)); // specifically good on BOOL
+ if( _max==0 ) return make(_min,-1);
+ return this;
+ }
+ @Override public Type makeZero() { return ZERO; }
+ @Override public TypeInteger glb() { return BOT; }
+ @Override int hash() { return Utils.fold(_min) * Utils.fold(_max); }
+ @Override public boolean eq( Type t ) {
+ TypeInteger i = (TypeInteger)t; // Contract
+ return _min==i._min && _max==i._max;
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeMem.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeMem.java
new file mode 100644
index 00000000..9ed4c7a8
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeMem.java
@@ -0,0 +1,74 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.lang.Long;
+import java.util.BitSet;
+import java.util.ArrayList;
+
+
+/**
+ * Represents a slice of memory corresponding to a set of aliases
+ */
+public class TypeMem extends Type {
+
+ // Which slice of memory?
+ // 0 means TOP, no slice.
+ // 0 means BOT, all memory.
+ // N means slice#N.
+ public final int _alias;
+ public final Type _t; // Memory contents, some scalar type
+
+ private TypeMem(int alias, Type t) {
+ super(TMEM);
+ assert alias!=0 || (t==Type.TOP || t==Type.BOTTOM);
+ _alias = alias;
+ _t = t;
+ }
+
+ public static TypeMem make(int alias, Type t) { return new TypeMem(alias,t).intern(); }
+ public static final TypeMem TOP = make(0, Type.TOP );
+ public static final TypeMem BOT = make(0, Type.BOTTOM);
+
+ public static void gather(ArrayList<Type> ts) { ts.add(make(1,Type.NIL)); ts.add(make(1,TypeInteger.ZERO)); ts.add(BOT); }
+
+ @Override
+ TypeMem xmeet(Type t) {
+ TypeMem that = (TypeMem) t; // Invariant: TypeMem and unequal
+ if( this==TOP ) return that;
+ if( that==TOP ) return this;
+ if( this==BOT ) return BOT;
+ if( that==BOT ) return BOT;
+ int alias = _alias==that._alias ? _alias : 0;
+ Type mt = _t.meet(that._t);
+ return make(alias,mt);
+ }
+
+ @Override
+ public Type dual() {
+ return make(_alias,_t.dual());
+ }
+
+ @Override public boolean isHigh() { return _t.isHigh(); }
+ @Override public Type glb() { return make(_alias,_t.glb()); }
+
+ @Override int hash() { return 9876543 + _alias + _t.hashCode(); }
+
+ @Override boolean eq(Type t) {
+ TypeMem that = (TypeMem) t; // Invariant
+ return _alias == that._alias && _t == that._t;
+ }
+
+ @Override public SB print(SB sb) {
+ sb.p("#");
+ if( _alias==0 ) return sb.p(_t._type==TTOP ? "TOP" : "BOT");
+ return _t.print(sb.p(_alias).p(":"));
+ }
+ @Override public SB gprint(SB sb) {
+ sb.p("#");
+ if( _alias==0 ) return sb.p(_t._type==TTOP ? "TOP" : "BOT");
+ return _t.gprint(sb.p(_alias).p(":"));
+ }
+
+ @Override public String str() { return toString(); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java
new file mode 100644
index 00000000..d7a8b17d
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java
@@ -0,0 +1,105 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+
+/**
+ * Represents a Pointer to memory.
+ *
+ * Null is generic pointer to non-existent memory.
+ * *void is a non-Null pointer to all possible refs, both structs and arrays.
+ * Pointers can be to specific struct and array types, or a union with Null.
+ * The distinguished *$BOT ptr represents union of *void and Null.
+ * The distinguished *$TOP ptr represents the dual of *$BOT.
+ */
+public class TypeMemPtr extends TypeNil {
+ // A TypeMemPtr is pair (obj,nil)
+ // where obj is a TypeStruct, possibly TypeStruct.BOT/TOP
+ // where nil is an explicit null is allowed or not
+
+ // Examples:
+ // (Person,false) - a not-nil Person
+ // (Person,true ) - a Person or a nil
+ // (BOT ,false) - a not-nil void* (unspecified struct)
+ // (TOP ,true ) - a nil
+
+ public final TypeStruct _obj;
+
+ private TypeMemPtr(byte nil, TypeStruct obj) {
+ super(TMEMPTR,nil);
+ assert obj!=null;
+ _obj = obj;
+ }
+ static TypeMemPtr make(byte nil, TypeStruct obj) { return new TypeMemPtr(nil, obj).intern(); }
+ public static TypeMemPtr makeNullable(TypeStruct obj) { return make((byte)3, obj); }
+ public static TypeMemPtr make(TypeStruct obj) { return new TypeMemPtr((byte)2, obj).intern(); }
+ public TypeMemPtr makeFrom(TypeStruct obj) { return obj==_obj ? this : make(_nil, obj); }
+ public TypeMemPtr makeNullable() { return makeFrom((byte)3); }
+ @Override TypeMemPtr makeFrom(byte nil) { return nil==_nil ? this : make(nil,_obj); }
+ @Override public TypeMemPtr makeRO() { return makeFrom(_obj.makeRO()); }
+ @Override public boolean isFinal() { return _obj.isFinal(); }
+
+ // An abstract pointer, pointing to either a Struct or an Array.
+ // Can also be null or not, so 4 choices {TOP,BOT} x {nil,not}
+ public static TypeMemPtr BOT = make((byte)3, TypeStruct.BOT);
+ public static TypeMemPtr TOP = BOT.dual();
+ public static TypeMemPtr NOTBOT = make((byte)2,TypeStruct.BOT);
+
+ public static TypeMemPtr TEST= make((byte)2, TypeStruct.TEST);
+ public static void gather(ArrayList<Type> ts) { ts.add(NOTBOT); ts.add(BOT); ts.add(TEST); }
+
+ @Override
+ public TypeNil xmeet(Type t) {
+ TypeMemPtr that = (TypeMemPtr) t;
+ return TypeMemPtr.make(xmeet0(that), (TypeStruct)_obj.meet(that._obj));
+ }
+
+ @Override
+ public TypeMemPtr dual() { return TypeMemPtr.make( dual0(), _obj.dual()); }
+
+ // RHS is NIL; do not deep-dual when crossing the centerline
+ @Override Type meet0() { return _nil==3 ? this : make((byte)3,_obj); }
+
+
+ // True if this "isa" t up to named structures
+ @Override public boolean shallowISA( Type t ) {
+ if( !(t instanceof TypeMemPtr that) ) return false;
+ if( this==that ) return true;
+ if( xmeet0(that)!=that._nil ) return false;
+ if( _obj==that._obj ) return true;
+ if( _obj._name.equals(that._obj._name) )
+ return true; // Shallow, do not follow matching names, just assume ok
+ throw Utils.TODO(); // return _obj.shallowISA(that._obj);
+ }
+
+ @Override public TypeMemPtr glb() { return make((byte)3,_obj.glb()); }
+ // Is forward-reference
+ @Override public boolean isFRef() { return _obj.isFRef(); }
+
+ @Override public int log_size() { return 2; } // (1<<2)==4-byte pointers
+
+ @Override int hash() { return _obj.hashCode() ^ super.hash(); }
+
+ @Override boolean eq(Type t) {
+ TypeMemPtr ptr = (TypeMemPtr)t; // Invariant
+ return _obj == ptr._obj && super.eq(ptr);
+ }
+
+ @Override public String str() {
+ if( this== NOTBOT) return "*void";
+ if( this== BOT) return "*void?";
+ return x()+"*"+_obj.str()+q();
+ }
+
+ @Override public SB print(SB sb) {
+ if( this== NOTBOT) return sb.p("*void");
+ if( this== BOT) return sb.p("*void?");
+ return _obj.print(sb.p(x()).p("*")).p(q());
+ }
+ @Override public SB gprint(SB sb) {
+ if( this== NOTBOT) return sb.p("*void");
+ if( this== BOT) return sb.p("*void?");
+ return _obj.gprint(sb.p(x()).p("*")).p(q());
+ }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeNil.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeNil.java
new file mode 100644
index 00000000..aee623ba
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeNil.java
@@ -0,0 +1,62 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+
+/**
+ * Nil-able Scalar types
+ */
+public abstract class TypeNil extends Type {
+ // 0 = high-subclass choice nil
+ // 1 = high-subclass no nil
+ // 2 = low -subclass no nil
+ // 3 = low -subclass also nil
+ final byte _nil;
+
+ TypeNil(byte t, byte nil ) { super(t); _nil = nil; }
+
+ public static void gather(ArrayList<Type> ts) { }
+
+ abstract TypeNil makeFrom(byte nil);
+
+ byte xmeet0(TypeNil that) { return (byte)Math.max(_nil,that._nil); }
+
+ byte dual0() { return (byte)(3-_nil); }
+
+ // RHS is NIL
+ abstract Type meet0();
+
+ // RHS is XNIL
+ Type meetX() {
+ return _nil==0 ? XNIL : (_nil<=2 ? TypePtr.NPTR : TypePtr.PTR);
+ }
+
+ Type nmeet(TypeNil tn) {
+ // Invariants: both are TypeNil subclasses and unequal classes.
+ // If this is TypePtr, we went to TypePtr.nmeet and not here.
+ // If that is TypePtr, this is not (invariant); reverse and go again.
+ if( tn instanceof TypePtr ts ) return ts.nmeet(this);
+
+ // Two mismatched TypeNil, no Scalar.
+ if( _nil==0 && tn._nil==0 ) return XNIL;
+ if( _nil<=2 && tn._nil<=2 ) return TypePtr.NPTR;
+ return TypePtr.PTR;
+ }
+
+ @Override public boolean isHigh () { return _nil <= 1; }
+ @Override public boolean isConstant () { return false; }
+ @Override public boolean isHighOrConst() { return isHigh() || isConstant(); }
+
+ @Override public Type glb() { return Type.NIL; }
+
+ public boolean notNull() { return _nil==1 || _nil==2; }
+ public boolean nullable() { return _nil==3; }
+
+ final String q() { return _nil == 1 || _nil == 2 ? "" : "?"; }
+ final String x() { return isHigh() ? "~" : ""; }
+
+ int hash() { return _nil<<17; }
+
+ boolean eq(TypeNil ptr) { return _nil == ptr._nil; }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypePtr.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypePtr.java
new file mode 100644
index 00000000..e9091c25
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypePtr.java
@@ -0,0 +1,53 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+
+/**
+ * Represents a Scalar; a single register-sized value.
+ */
+public class TypePtr extends TypeNil {
+
+ private TypePtr(byte nil) { super(TPTR,nil); }
+
+ // An abstract pointer, pointing to either a Struct or an Array.
+ // Can also be null or not, so 4 choices {TOP,BOT} x {nil,not}
+ public static TypePtr XPTR = new TypePtr((byte)0).intern();
+ public static TypePtr XNPTR= new TypePtr((byte)1).intern();
+ public static TypePtr NPTR = new TypePtr((byte)2).intern();
+ public static TypePtr PTR = new TypePtr((byte)3).intern();
+ private static final TypePtr[] PTRS = new TypePtr[]{XPTR,XNPTR,NPTR,PTR};
+
+ public static void gather(ArrayList<Type> ts) { ts.add(PTR); ts.add(NPTR); }
+
+ TypeNil makeFrom(byte nil) { throw Utils.TODO(); }
+
+ @Override public TypeNil xmeet(Type t) {
+ TypePtr that = (TypePtr) t;
+ return PTRS[xmeet0(that)];
+ }
+
+ @Override public TypePtr dual() { return PTRS[dual0()]; }
+
+ // High scalar loses, low scalar wins
+ @Override TypeNil nmeet(TypeNil tn) {
+ if( _nil==0 ) return tn; // High scalar loses
+ if( _nil==1 ) return tn.makeFrom(xmeet0(tn)); // High scalar loses
+ if( _nil==2 ) return tn._nil==3 ? PTR : NPTR; // Low scalar wins
+ return PTR; // this
+ }
+
+
+ // RHS is NIL
+ @Override Type meet0() { return isHigh() ? NIL : PTR; }
+ // RHS is XNIL
+ // 0->xscalar, 1->nscalar, 2->nscalar, 3->scalar
+ @Override Type meetX() { return _nil==0 ? XNIL : (_nil==3 ? PTR : NPTR); }
+
+ @Override public TypePtr glb() { return PTR; }
+
+ private static final String[] STRS = new String[]{"~ptr","~nptr","nptr","ptr"};
+ @Override public String str() { return STRS[_nil]; }
+ @Override public SB print(SB sb) { return sb.p(str()); }
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeRPC.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeRPC.java
new file mode 100644
index 00000000..ec2f5f0a
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeRPC.java
@@ -0,0 +1,100 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+import java.util.BitSet;
+import java.util.HashSet;
+
+/**
+ * Return Program Control or Return PC or RPC
+ */
+public class TypeRPC extends Type {
+
+ // A set of CallEndNode IDs (or StopNode); commonly just one.
+ // Basically a sparse bit set
+ final HashSet<Integer> _rpcs;
+
+ // If true, invert the meaning of the bits
+ final boolean _any;
+
+ private TypeRPC(boolean any, HashSet<Integer> rpcs) {
+ super(TRPC);
+ _any = any;
+ _rpcs = rpcs;
+ }
+ private static TypeRPC make(boolean any, HashSet<Integer> rpcs) {
+ return new TypeRPC(any,rpcs).intern();
+ }
+
+ public static TypeRPC constant(int cend) {
+ HashSet<Integer> rpcs = new HashSet<>();
+ rpcs.add(cend);
+ return make(false,rpcs);
+ }
+
+ public static final TypeRPC BOT = make(true,new HashSet<>());
+ private static final TypeRPC TEST2 = constant(2);
+ private static final TypeRPC TEST3 = constant(2);
+
+ public static void gather(ArrayList<Type> ts) { ts.add(BOT); ts.add(TEST2); ts.add(TEST3); }
+
+ @Override public String str() {
+ if( _rpcs.isEmpty() )
+ return _any ? "$[ALL]" : "$[]";
+ if( _rpcs.size()==1 )
+ for( Integer rpc : _rpcs )
+ return _any ? "$[-"+rpc+"]" : "$["+rpc+"]";
+ return "$["+(_any ? "-" : "")+_rpcs+"]";
+ }
+
+ @Override public boolean isConstant() {
+ return !_any && _rpcs.size()==1;
+ }
+
+ @Override
+ public TypeRPC xmeet(Type other) {
+ TypeRPC rpc = (TypeRPC)other;
+ // If the two sets are equal, the _any must be unequal (invariant),
+ // so they cancel and all bits are set.
+ if( _rpcs.equals(rpc._rpcs) )
+ return BOT;
+ // Classic union of bit sets (which might be infinite).
+ HashSet<Integer> lhs = _rpcs, rhs = rpc._rpcs;
+ // Smaller on left
+ if( lhs.size() > rhs.size() ) { lhs = rpc._rpcs; rhs = _rpcs; }
+
+ HashSet<Integer> rpcs = new HashSet<>();
+ boolean any = true;
+ // If both sets are infinite, intersect.
+ if( _any && rpc._any ) {
+ for( Integer i : lhs ) if( rhs.contains(i) ) rpcs.add(i);
+
+ } else if( !_any && !rpc._any ) {
+ // if neither set is infinite, union.
+ rpcs.addAll( lhs );
+ rpcs.addAll( rhs );
+ any = false;
+ } else {
+ // If one is infinite, subtract the other from it.
+ HashSet<Integer> sub = _any ? rpc._rpcs : _rpcs;
+ HashSet<Integer> inf = _any ? _rpcs : rpc._rpcs;
+ for( Integer i : inf )
+ if( inf.contains(i) && !sub.contains(i) )
+ rpcs.add(i);
+ }
+ return make(any,rpcs);
+ }
+
+ @Override
+ public Type dual() { return make(!_any,_rpcs); }
+
+ @Override
+ int hash() { return _rpcs.hashCode() ^ (_any ? -1 : 0) ; }
+ @Override
+ public boolean eq( Type t ) {
+ TypeRPC rpc = (TypeRPC)t; // Contract
+ return _any==rpc._any && _rpcs.equals(rpc._rpcs);
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeStruct.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeStruct.java
new file mode 100644
index 00000000..6c5cb8d4
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeStruct.java
@@ -0,0 +1,248 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import com.seaofnodes.simple.Utils;
+import java.util.ArrayList;
+
+/**
+ * Represents a struct type.
+ */
+public class TypeStruct extends Type {
+
+ // A Struct has a name and a set of fields; the fields themselves have
+ // names, types and aliases. The name has no semantic meaning, but is
+ // useful for debugging. Briefly during parsing a Struct can be a
+ // forward-ref; in this case the _fields array is null.
+
+ // Its illegal to attempt to load a field from a forward-ref struct.
+
+ // Example: "int rez = new S.x; struct S { int x; } return rez;" // Error, S not defined
+ // Rewrite: "struct S { int x; } int rez = new S.x; return rez;" // Ok, no forward ref
+ //
+ // During the normal optimization run, struct types "bottom out" at further
+ // struct references, so we don't have to handle e.g. cyclic types. The
+ // "bottom out" is again the forward-ref struct.
+ public final String _name;
+ public final Field[] _fields;
+
+ TypeStruct(String name, Field[] fields) {
+ super(TSTRUCT);
+ _name = name;
+ _fields = fields;
+ }
+
+ // All fields directly listed
+ public static TypeStruct make(String name, Field... fields) { return new TypeStruct(name, fields).intern(); }
+ public static final TypeStruct TOP = make("$TOP",new Field[0]);
+ public static final TypeStruct BOT = make("$BOT",new Field[0]);
+ public static final TypeStruct TEST = make("test",new Field[]{Field.TEST});
+ // Forward-ref version
+ public static TypeStruct makeFRef(String name) { return make(name, (Field[])null); }
+ // Make a read-only version
+ @Override public TypeStruct makeRO() {
+ if( isFinal() ) return this;
+ Field[] flds = new Field[_fields.length];
+ for( int i=0; i<flds.length; i++ )
+ flds[i] = _fields[i].makeRO();
+ return make(_name,flds);
+ }
+
+ // Array
+ public static TypeStruct makeAry(TypeInteger len, int lenAlias, Type body, int bodyAlias) {
+ assert body instanceof TypeInteger || body instanceof TypeFloat || (body instanceof TypeNil tn && tn.nullable());
+ assert len.isa(TypeInteger.U32);
+ return make("[" + body.str() + "]",
+ Field.make("#" ,len , lenAlias,true ),
+ Field.make("[]",body,bodyAlias,false));
+ }
+
+ // A pair of self-cyclic types
+ private static final TypeStruct S1F = makeFRef("S1");
+ private static final TypeStruct S2F = makeFRef("S2");
+ public static final TypeStruct S1 = make("S1", Field.make("a", TypeInteger.BOT, -1, false), Field.make("s2",TypeMemPtr.make((byte)2,S2F),-2, false) );
+ private static final TypeStruct S2 = make("S2", Field.make("b", TypeFloat .F64, -3, false), Field.make("s1",TypeMemPtr.make((byte)2,S1F),-4, false) );
+
+ private static final TypeStruct ARY = makeAry(TypeInteger.U32,-1,TypeInteger.BOT,-2);
+
+ public static void gather(ArrayList<Type> ts) { ts.add(TEST); ts.add(BOT); ts.add(S1); ts.add(S2); ts.add(ARY); }
+
+ // Find field index by name
+ public int find(String fname) {
+ for( int i=0; i<_fields.length; i++ )
+ if( _fields[i]._fname.equals(fname) )
+ return i;
+ return -1;
+ }
+ public Field field(String fname) {
+ int idx = find(fname);
+ return idx== -1 ? null : _fields[idx];
+ }
+
+ // Find field index by alias
+ public int findAlias( int alias ) {
+ for( int i=0; i<_fields.length; i++ )
+ if( _fields[i]._alias==alias )
+ return i;
+ return -1;
+ }
+
+
+ @Override
+ Type xmeet(Type t) {
+ TypeStruct that = (TypeStruct) t;
+ if( this==TOP ) return that;
+ if( that==TOP ) return this;
+ if( this==BOT ) return BOT;
+ if( that==BOT ) return BOT;
+
+ // Within the same compilation unit, struct names are unique. If the
+ // names differ, its different structs. Across many compilation units,
+ // structs with the same name but different field layouts can be
+ // interned... which begs the question:
+ // "What is the meet of structs from two different compilation units?"
+ // And the answer is: "don't ask".
+ if( !_name.equals(that._name) )
+ return BOT; // It's a struct; that's about all we know
+ if( this._fields==null ) return that;
+ if( that._fields==null ) return this;
+ if( _fields.length != that._fields.length ) return BOT;
+ // Just do field meets
+ Field[] flds = new Field[_fields.length];
+ for( int i=0; i<_fields.length; i++ ) {
+ Field f0 = _fields[i], f1 = that._fields[i];
+ if( !f0._fname.equals(f1._fname) || f0._alias != f1._alias )
+ return BOT;
+ flds[i] = (Field)f0.meet(f1);
+ }
+ return make(_name,flds);
+ }
+
+ @Override
+ public TypeStruct dual() {
+ if( this==TOP ) return BOT;
+ if( this==BOT ) return TOP;
+ if( _fields == null ) return this;
+ Field[] flds = new Field[_fields.length];
+ for( int i=0; i<_fields.length; i++ )
+ flds[i] = _fields[i].dual();
+ return make(_name,flds);
+ }
+
+ // Keeps the same struct, but lower-bounds all fields.
+ @Override public TypeStruct glb() {
+ if( _glb() ) return this;
+ // Need to glb each field
+ Field[] flds = new Field[_fields.length];
+ for( int i=0; i<_fields.length; i++ )
+ flds[i] = _fields[i].glb();
+ return make(_name,flds);
+ }
+ private boolean _glb() {
+ if( _fields!=null )
+ for( Field f : _fields )
+ if( f.glb() != f )
+ return false;
+ return true;
+ }
+
+ // Is forward-reference
+ @Override public boolean isFRef() { return _fields==null; }
+ // All fields are final
+ @Override public boolean isFinal() {
+ if( _fields==null ) return true;
+ for( Field fld : _fields )
+ if( !fld.isFinal() )
+ return false;
+ return true;
+ }
+
+ @Override
+ boolean eq(Type t) {
+ TypeStruct ts = (TypeStruct)t; // Invariant
+ if( !_name.equals(ts._name) )
+ return false;
+ if( _fields == ts._fields ) return true;
+ if( _fields==null || ts._fields==null ) return false;
+ if( _fields.length!=ts._fields.length )
+ return false;
+ for( int i = 0; i < _fields.length; i++ )
+ if( _fields[i] != ts._fields[i] )
+ return false;
+ return true;
+ }
+
+ @Override
+ int hash() {
+ long hash = _name.hashCode();
+ if( _fields != null )
+ for( Field f : _fields )
+ hash = Utils.rot(hash,13) ^ f.hashCode();
+ return Utils.fold(hash);
+ }
+
+ @Override
+ public SB print(SB sb) {
+ sb.p(_name);
+ if( _fields == null ) return sb; // Forward reference struct, just print the name
+ sb.p(" {");
+ for( Field f : _fields )
+ f._type.print(sb).p(f._final ? " " : " !").p(f._fname).p("; ");
+ return sb.p("}");
+ }
+ @Override public SB gprint( SB sb ) { return sb.p(_name); }
+
+ @Override public String str() { return _name; }
+
+
+ public boolean isAry() { return _fields.length==2 && _fields[1]._fname.equals("[]"); }
+
+ public int aryBase() {
+ assert isAry();
+ if( _offs==null ) _offs = offsets();
+ return _offs[1];
+ }
+ public int aryScale() {
+ assert isAry();
+ return _fields[1]._type.log_size();
+ }
+
+
+ // Field offsets as packed byte offsets
+ private int[] _offs; // Lazily computed and not part of the type semantics
+ public int offset(int idx) {
+ if( _offs==null ) _offs = offsets();
+ return _offs[idx];
+ }
+ private int[] offsets() { // Field byte offsets
+ // Compute a layout for a collection of fields
+ assert _fields != null; // No forward refs
+
+ // Array layout is different: len,[pad],body...
+ if( isAry() )
+ return _offs = new int[]{ 0, _fields[1]._type.log_size() < 3 ? 4 : 8 };
+
+ // Compute a layout
+ int[] cnts = new int[4]; // Count of fields at log field size
+ for( Field f : _fields )
+ cnts[f._type.log_size()]++; // Log size is 0(byte), 1(i16/u16), 2(i32/f32), 3(i64/dbl)
+ int off = 0, idx = 0; // Base common struct fields go here, e.g. Mark/Klass
+ // Compute offsets to the start of each power-of-2 aligned fields.
+ int[] offs = new int[4];
+ for( int i=3; i>=0; i-- ) {
+ offs[i] = off;
+ off += cnts[i]<<i;
+ }
+ // Assign offsets to all fields.
+ // Really a hidden radix sort.
+ _offs = new int[_fields.length+1];
+ for( Field f : _fields ) {
+ int log = f._type.log_size();
+ _offs[idx++] = offs[log]; // Field offset
+ offs[log] += 1<<log; // Next field offset at same alignment
+ cnts[log]--; // Count down, should be all zero at end
+ }
+ _offs[_fields.length] = (off+7)& ~7; // Round out to max alignment
+ return _offs;
+ }
+
+}
diff --git a/chapter20/src/main/java/com/seaofnodes/simple/type/TypeTuple.java b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeTuple.java
new file mode 100644
index 00000000..6d3a2b69
--- /dev/null
+++ b/chapter20/src/main/java/com/seaofnodes/simple/type/TypeTuple.java
@@ -0,0 +1,97 @@
+package com.seaofnodes.simple.type;
+
+import com.seaofnodes.simple.SB;
+import java.util.ArrayList;
+
+public class TypeTuple extends Type {
+
+ public final Type[] _types;
+
+ private TypeTuple(Type[] types) { super(TTUPLE); _types = types; }
+ public static TypeTuple make(Type... types) { return new TypeTuple(types).intern(); }
+
+ public static final TypeTuple BOT = new TypeTuple(new Type[0]).intern();
+ public static final TypeTuple TOP = new TypeTuple(null).intern();
+
+ public static final TypeTuple TEST = make(TypeInteger.BOT,TypeMemPtr.TEST);
+ public static final TypeTuple START= make(Type.CONTROL,TypeMem.TOP,TypeInteger.BOT);
+ public static final TypeTuple MAIN = make(TypeInteger.BOT);
+ public static final TypeTuple RET = make(Type.CONTROL,TypeMem.BOT,Type.BOTTOM);
+
+ public static final TypeTuple IF_BOTH = make(new Type[]{Type. CONTROL,Type. CONTROL});
+ public static final TypeTuple IF_NEITHER = make(new Type[]{Type.XCONTROL,Type.XCONTROL});
+ public static final TypeTuple IF_TRUE = make(new Type[]{Type. CONTROL,Type.XCONTROL});
+ public static final TypeTuple IF_FALSE = make(new Type[]{Type.XCONTROL,Type. CONTROL});
+
+ public static void gather(ArrayList<Type> ts) { ts.add(BOT); ts.add(TEST); ts.add(START); ts.add(MAIN); ts.add(IF_TRUE); }
+
+ @Override
+ Type xmeet(Type other) {
+ TypeTuple tt = (TypeTuple)other; // contract from xmeet
+ if( this==TOP ) return other;
+ if( tt ==TOP ) return this ;
+ if( _types.length != tt._types.length )
+ return BOT;
+ Type[] ts = new Type[_types.length];
+ for( int i=0; i<_types.length; i++ )
+ ts[i] = _types[i].meet(tt._types[i]);
+ return make(ts);
+ }
+
+ @Override public TypeTuple dual() {
+ if( this==TOP ) return BOT;
+ if( this==BOT ) return TOP;
+ Type[] ts = new Type[_types.length];
+ for( int i=0; i<_types.length; i++ )
+ ts[i] = _types[i].dual();
+ return make(ts);
+ }
+
+ @Override
+ public Type glb() {
+ Type[] ts = new Type[_types.length];
+ for( int i=0; i<_types.length; i++ )
+ ts[i] = _types[i].glb();
+ return make(ts);
+ }
+
+ @Override public String str() { return print(new SB()).toString(); }
+
+ @Override public SB print(SB sb) {
+ if( this==TOP ) return sb.p("[TOP]");
+ if( this==BOT ) return sb.p("[BOT]");
+ sb.p("[ ");
+ for( Type t : _types )
+ t.print(sb).p(", ");
+ return sb.unchar(2).p("]");
+ }
+ @Override public SB gprint(SB sb) {
+ if( this==TOP ) return sb.p("[TOP]");
+ if( this==BOT ) return sb.p("[BOT]");
+ sb.p("[ ");
+ for( Type t : _types )
+ t.gprint(sb).p(", ");
+ return sb.unchar(2).p("]");
+ }
+
+ @Override
+ int hash() {
+ int sum = 0;
+ if( _types!=null ) for( Type type : _types ) sum ^= type.hashCode();
+ return sum;
+ }
+
+ @Override
+ boolean eq( Type t ) {
+ TypeTuple tt = (TypeTuple)t; // Contract
+ if( _types==null && tt._types==null ) return true;
+ if( _types==null || tt._types==null ) return false;
+ if( _types.length != tt._types.length ) return false;
+ for( int i=0; i<_types.length; i++ )
+ if( _types[i]!=tt._types[i] )
+ return false;
+ return true;
+ }
+
+
+}