diff options
Diffstat (limited to 'chapter15/src/main')
4 files changed, 65 insertions, 1 deletions
diff --git a/chapter15/src/main/java/com/seaofnodes/simple/node/RegionNode.java b/chapter15/src/main/java/com/seaofnodes/simple/node/RegionNode.java index d5105614..0c7cd1e4 100644 --- a/chapter15/src/main/java/com/seaofnodes/simple/node/RegionNode.java +++ b/chapter15/src/main/java/com/seaofnodes/simple/node/RegionNode.java @@ -72,9 +72,65 @@ public class RegionNode extends CFGNode { p1.in(0) instanceof IfNode iff ) return iff.ctrl(); + + + // Look for direct uses of a guarded expression, and replace with the guard result. + if( !(idom() instanceof StartNode) && // Dead or dying + !(this instanceof LoopNode) ) { + VISIT.clear(); + boolean progress = false; + outer: + for( int i=1; i<nIns(); i++ ) { + CFGNode idom = cfg(i); + while( !(idom instanceof CProjNode cproj) ) { + idom = idom.idom(); + if( idom==null || idom.idepth() < idom().idepth() ) + continue outer; + } + if( cproj.cfg0() instanceof IfNode iff && cproj.compute()==Type.CONTROL ) { + VISIT.set(iff.pred()._nid); + for( Node out : _outputs ) + if( out instanceof PhiNode phi ) + progress |= walk(iff,cproj,phi.in(i)); + } + } + if( progress ) + return this; + } + return null; } + // A walk that can be cutoff early + private static final BitSet VISIT = new BitSet(); + private static boolean walk( IfNode iff, CProjNode cproj, Node n ) { + if( VISIT.get(n._nid) ) return false; + VISIT.set(n._nid); + if( n instanceof CFGNode ) return false; + if( n.in(0)!=null && n.cfg0().idepth() < iff.idepth() ) + return false; + boolean progress = false; + Node pred = iff.pred(); + for( int i=1; i<n.nIns(); i++ ) { + // Using a tested value + if( n.in(i) == pred && !(n instanceof CastNode) ) { + // Checking pred for T/F + Type t = pred._type; + Type tcast = cproj._idx==0 ? t.nonZero() : t.makeInit(); + if( t!=tcast ) { // Progress to cast + Node cast = new CastNode( tcast, cproj, pred ).peephole(); + n.setDef( i, cast ); + IterPeeps.add(n); + progress = true; + } + } + if( n.in(i)!=null ) + progress |= walk(iff,cproj,n.in(i)); + } + return progress; + } + + private int findDeadInput() { for( int i=1; i<nIns(); i++ ) if( in(i)._type==Type.XCONTROL ) diff --git a/chapter15/src/main/java/com/seaofnodes/simple/type/Type.java b/chapter15/src/main/java/com/seaofnodes/simple/type/Type.java index 983fcf98..989eff9e 100644 --- a/chapter15/src/main/java/com/seaofnodes/simple/type/Type.java +++ b/chapter15/src/main/java/com/seaofnodes/simple/type/Type.java @@ -82,6 +82,7 @@ public class Type { public StringBuilder typeName( StringBuilder sb) { return print(sb); } public Type makeInit() { return null; } + public Type nonZero() { return glb(); } // ---------------------------------------------------------- diff --git a/chapter15/src/main/java/com/seaofnodes/simple/type/TypeInteger.java b/chapter15/src/main/java/com/seaofnodes/simple/type/TypeInteger.java index fca3362e..042b4ba8 100644 --- a/chapter15/src/main/java/com/seaofnodes/simple/type/TypeInteger.java +++ b/chapter15/src/main/java/com/seaofnodes/simple/type/TypeInteger.java @@ -113,8 +113,14 @@ public class TypeInteger extends Type { } @Override public TypeInteger dual() { return make(_max,_min); } - @Override public Type glb() { return BOT; } + @Override public TypeInteger glb() { return BOT; } @Override public TypeInteger makeInit() { return ZERO; } + @Override public TypeInteger nonZero() { + if( isHigh() ) return this; + if( _min==0 ) return make(1,_max); // specifically good on BOOL + if( _max==0 ) return make(_min,-1); + return this; + } @Override int hash() { return (int)((_min ^ (_min>>32)) *(_max ^ (_max>>32))); } @Override public boolean eq( Type t ) { diff --git a/chapter15/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java b/chapter15/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java index 7743c80d..8b484235 100644 --- a/chapter15/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java +++ b/chapter15/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java @@ -58,6 +58,7 @@ public class TypeMemPtr extends Type { @Override public TypeMemPtr glb() { return make(_obj.glb(),true); } @Override public TypeMemPtr makeInit() { return NULLPTR; } + @Override public Type nonZero() { return VOIDPTR; } @Override public boolean isHigh() { return this==TOP; } |