Chapter renumber, and split ch 17

Renumber chapters 10a, 10b, 11, 12, 13, 14 -> 10, 11, 13, 12, [11,14].
Split ch 17 into a 17a and 17b; shuffle around im/mutable syntax to be consistent, and present it more slowly.
THe new immutable syntax is pushed through all later chapters

42 files changed, 288 insertions, 1396 deletions

diff --git a/chapter11/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java b/chapter11/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java
deleted file mode 100644
index 35b34576..00000000
--- a/chapter11/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java
+++ /dev/null
@@ -1,272 +0,0 @@
- 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( StopNode stop ) {
-        fixLoops(stop);
-        schedEarly();
-        Parser.SCHEDULED = true;
-        schedLate(stop);
-    }
-
-    // ------------------------------------------------------------------------
-    // Backwards walk on the CFG only, looking for unreachable code - which has
-    // to be an infinite loop.  Insert a bogus never-taken exit to Stop, so the
-    // loop becomes reachable.  Also, set loop nesting depth
-    private static void fixLoops(StopNode stop) {
-        // Backwards walk from Stop, looking for unreachable code
-        BitSet visit = new BitSet();
-        HashSet<CFGNode> unreach = new HashSet<>();
-        unreach.add(Parser.START);
-        for( Node ret : stop._inputs )
-            ((ReturnNode)ret).walkUnreach(visit,unreach);
-        if( unreach.isEmpty() ) return;
-
-        // Forwards walk from unreachable, looking for loops with no exit test.
-        visit.clear();
-        for( CFGNode cfg : unreach )
-            walkInfinite(cfg,visit,stop);
-        // Set loop depth on remaining graph
-        unreach.clear();
-        visit.clear();
-        for( Node ret : stop._inputs )
-            ((ReturnNode)ret).walkUnreach(visit,unreach);
-        assert unreach.isEmpty();
-    }
-
-
-    // Forwards walk over previously unreachable, looking for loops with no
-    // exit test.
-    static private void walkInfinite( CFGNode n, BitSet visit, StopNode stop ) {
-        if( visit.get(n._nid) ) return; // Been there, done that
-        visit.set(n._nid);
-        if( n instanceof LoopNode loop )
-            loop.forceExit(stop);
-        for( Node use : n._outputs )
-            if( use instanceof CFGNode cfg )
-                walkInfinite(cfg,visit,stop);
-    }
-
-    // ------------------------------------------------------------------------
-    private static void schedEarly() {
-        ArrayList<CFGNode> rpo = new ArrayList<>();
-        BitSet visit = new BitSet();
-        _rpo_cfg(Parser.START, visit, rpo);
-        // Reverse Post-Order on CFG
-        for( int j=rpo.size()-1; j>=0; j-- ) {
-            CFGNode cfg = rpo.get(j);
-            cfg.loopDepth();
-            for( Node n : cfg._inputs )
-                _schedEarly(n,visit);
-            // In dead infinite loops, entire code blocks may be unreachable
-            // from below.  Reach down from the CFG to their Phis so their
-            // inputs are scheduled too.
-            if( cfg instanceof RegionNode ) {
-                int len = cfg.nOuts();
-                for( int i=0; i<len; i++ )
-                    if( cfg.out(i) instanceof PhiNode phi )
-                        _schedEarly(phi,visit);
-            }
-        }
-    }
-
-    // Post-Order of CFG
-    private static void _rpo_cfg(Node n, BitSet visit, ArrayList<CFGNode> rpo) {
-        if( !(n instanceof CFGNode cfg) || visit.get(cfg._nid) )
-            return;             // Been there, done that
-        visit.set(cfg._nid);
-        for( Node use : cfg._outputs )
-            _rpo_cfg(use,visit,rpo);
-        rpo.add(cfg);
-    }
-
-    private static void _schedEarly(Node n, BitSet visit) {
-        if( n==null || visit.get(n._nid) ) return; // Been there, done that
-        visit.set(n._nid);
-        // Schedule inputs first, except Phis: following their backedges would
-        // enter a data cycle before its control has been scheduled.
-        for( Node def : n._inputs )
-            if( def!=null && !(def instanceof PhiNode) )
-                _schedEarly(def,visit);
-        // An existing edge 0 already supplies control (or a Phi/Proj binding).
-        if( n.in(0)==null ) {
-            // Schedule at deepest input
-            CFGNode early = Parser.START; // Maximally early, lowest idepth
-            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);              // First place this can go
-        }
-    }
-
-    // ------------------------------------------------------------------------
-    private static void schedLate( StopNode stop) {
-        CFGNode[] late = new CFGNode[Node.UID()];
-        Node[] ns = new Node[Node.UID()];
-        // Record Load NIDs at all their CFG block choices, then check against
-        // Store block choices to force a Load above an anti-dependent Store.
-        int[] anti = new int[Node.UID()];
-        // Breadth-first scheduling
-        breadth(stop,ns,late,anti);
-
-        // 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, int[] anti) {
-        // 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();
-            // These nodes have a fixed late placement at their original control.
-            else if( n instanceof ProjNode || n instanceof NewNode || n==Parser.ZERO ) late[n._nid] = n.cfg0();
-            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( antiUse(ld,memuse) && late[memuse._nid]==null )
-                            continue outer;
-
-                // All uses done, schedule
-                _doSchedLate(n,ns,late,anti);
-            }
-
-            // A use just finished; reconsider its inputs and waiting loads,
-            // even when the shared memory input was already scheduled.
-            for( Node def : n._inputs ) {
-                if( def==null ) continue;
-                if( late[def._nid]==null ) work.push(def);
-                for( Node out : def._outputs )
-                    if( out instanceof LoadNode ld && late[ld._nid]==null )
-                        work.push(ld);
-            }
-            if( n instanceof LoopNode loop )
-                for( Node phi : loop._outputs )
-                    if( phi instanceof PhiNode && late[phi._nid]==null )
-                        work.push(phi);
-        }
-    }
-
-    private static void _doSchedLate(Node n, Node[] ns, CFGNode[] late, int[] anti) {
-        // 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).domLCA(lca);
-
-        // Loads may need anti-dependencies, raising their LCA
-        if( n instanceof LoadNode load )
-            lca = find_anti_dep(lca,load,early,late,anti);
-
-        // 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).domLCA(found); // Can be more than one matching input.
-        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 instanceof NeverNode ||
-            lca.idepth() > best.idepth() ||
-            best instanceof IfNode;
-    }
-
-    // Only a store or memory Phi covering this alias can constrain a load.
-    // MemMerge packages slices without overwriting them.
-    private static boolean antiUse(LoadNode load, Node use) {
-        return switch( use ) {
-        case StoreNode st -> st._alias==load._alias;
-        case MemPhiNode phi -> phi._alias==load._alias;
-        case BulkMemPhiNode phi -> !phi.isSplit(load._alias);
-        default -> false;
-        };
-    }
-
-    private static CFGNode find_anti_dep(CFGNode lca, LoadNode load, CFGNode early, CFGNode[] late, int[] anti) {
-        // 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() )
-            anti[cfg._nid] = load._nid;
-        // Walk load->mem uses, looking for Stores causing an anti-dep
-        for( Node mem : load.mem()._outputs ) {
-            if( !antiUse(load,mem) ) continue;
-            switch( mem ) {
-            case StoreNode st:
-                lca = anti_dep(load,late[st._nid],st.cfg0(),lca,st,anti);
-                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,anti);
-                break;
-            default: throw Utils.TODO();
-            }
-        }
-        return lca;
-    }
-
-    //
-    private static CFGNode anti_dep( LoadNode load, CFGNode stblk, CFGNode defblk, CFGNode lca, Node st, int[] anti ) {
-        // Preserve the full store range for the earlier evaluator scheduler.
-        // It places nodes independently of GCM and may hoist this store.
-        for( ; stblk != defblk.idom(); stblk = stblk.idom() ) {
-            // Store and Load overlap, need anti-dependence
-            if( anti[stblk._nid]==load._nid ) {
-                lca = stblk.domLCA(lca); // Raise Loads LCA
-                if( lca == stblk && st != null && Utils.find(st._inputs,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/chapter11/src/main/java/com/seaofnodes/simple/IRPrinter.java b/chapter11/src/main/java/com/seaofnodes/simple/IRPrinter.java
index 7e93e9da..d5ab15fe 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/IRPrinter.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/IRPrinter.java
@@ -8,6 +8,7 @@ public final class IRPrinter extends IRAdapter<Node> {
     private static final com.seaofnodes.print.IRPrinter<Node> PRINT =
         new com.seaofnodes.print.IRPrinter<>(new IRPrinter());
     @Override public String type(Node n) { return n._type==null ? "" : n._type.str(); }
+    @Override public int inputColumns() { return 3; }
     @Override public String inputMark(Node n, Node def) { return n instanceof MemMergeNode && def instanceof MemMergeNode ? "^" : " "; }
     @Override public Kind kind(Node n) {
         if( n instanceof StartNode ) return Kind.START;
@@ -17,15 +18,13 @@ public final class IRPrinter extends IRAdapter<Node> {
         if( n instanceof PhiNode ) return Kind.PHI;
         if( n instanceof ReturnNode ) return Kind.RETURN;
         if( n instanceof ConstantNode ) return Kind.CONSTANT;
-        if( n instanceof CProjNode ) return Kind.CPROJ;
-        if( n instanceof ProjNode ) return n instanceof CFGNode ? Kind.CPROJ : Kind.PROJ;
-        if( n instanceof CFGNode ) return Kind.CTRL;
+        if( n instanceof ProjNode ) return n.isCFG() ? Kind.CPROJ : Kind.PROJ;
+        if( n.isCFG() ) return Kind.CTRL;
         if( n instanceof MultiNode ) return Kind.MULTI;
         return Kind.DATA;
     }
     @Override public int index(Node n) {
         if( n instanceof ProjNode p ) return p._idx;
-        if( n instanceof CProjNode p ) return p._idx;
         return n._nid;
     }
 
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/IterPeeps.java b/chapter11/src/main/java/com/seaofnodes/simple/IterPeeps.java
index 9d2b913f..7075d526 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/IterPeeps.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/IterPeeps.java
@@ -98,7 +98,6 @@ public abstract class IterPeeps {
             if( obs != null ) obs.after(n, x, true);
         }
 
-        GlobalCodeMotion.buildCFG(stop);
         return stop;
     }
 
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/Parser.java b/chapter11/src/main/java/com/seaofnodes/simple/Parser.java
index fb4dfdf8..3b5f2721 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/Parser.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/Parser.java
@@ -31,18 +31,12 @@ public class Parser {
      */
     public static StartNode START;
 
-    public static ConstantNode ZERO;
-    public static XCtrlNode XCTRL;
-
     public StopNode STOP;
 
     // Field identities are independent of the memory graph and Start's tuple.
     private final HashMap<String,Integer> _aliases = new HashMap<>();
     private int _alias = 2;
 
-    // Debugger Printing.
-    public static boolean SCHEDULED; // True if debug printer can use schedule info
-
     // The Lexer.  Thin wrapper over a byte[] buffer with a cursor.
     private final Lexer _lexer;
 
@@ -96,14 +90,11 @@ public class Parser {
         Node.reset();
         IterPeeps.reset();
         OBJS.clear();
-        SCHEDULED = false;
         _lexer = new Lexer(source);
         _scope = new ScopeNode();
         _continueScope = _breakScope = null;
         START = new StartNode(new Type[]{ Type.CONTROL, TypeMem.BOT, arg });
         STOP = new StopNode(source);
-        ZERO = new ConstantNode(TypeInteger.constant(0)).peephole().keep();
-        XCTRL= new XCtrlNode().peephole().keep();
     }
 
     public Parser(String source) {
@@ -126,12 +117,10 @@ public class Parser {
         _xScopes.push(_scope);
         // Enter a new scope for the initial control and arguments
         _scope.push();
-        _scope.define(ScopeNode.CTRL, Type.CONTROL   , new CProjNode(START, 0, ScopeNode.CTRL).peephole());
-        _scope.define(ScopeNode.ARG0, TypeInteger.BOT, new  ProjNode(START, 2, ScopeNode.ARG0).peephole());
+        _scope.define(ScopeNode.CTRL, Type.CONTROL   , new ProjNode(START, 0, ScopeNode.CTRL).peephole());
+        _scope.define(ScopeNode.ARG0, TypeInteger.BOT, new ProjNode(START, 2, ScopeNode.ARG0).peephole());
         _scope.define("$mem", TypeMem.BOT, new ProjNode(START, 1, "$mem").peephole());
         parseBlock();
-        if( ctrl()._type==Type.CONTROL )
-            STOP.addReturn(new ReturnNode(ctrl(), new ConstantNode(TypeInteger.constant(0)).peephole(), _scope).peephole());
         _scope.pop();
         _xScopes.pop();
         if (!_lexer.isEOF()) throw error("Syntax error, unexpected " + _lexer.getAnyNextToken());
@@ -215,9 +204,9 @@ public class Parser {
         require("}");
         // Build and install the TypeStruct
         TypeStruct ts = TypeStruct.make(typeName, fields);
-        OBJS.put(typeName, ts); // Insert the struct name in the collection of all struct names
         _aliases.put(typeName,_alias);
         _alias += ts._fields.length;
+        OBJS.put(typeName, ts); // Insert the struct name in the collection of all struct names
         return parseStatement();
     }
 
@@ -259,8 +248,8 @@ public class Parser {
         // 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();
+        Node ifT = new ProjNode(ifNode.  keep(), 0, "True" ).peephole().keep();
+        Node ifF = new ProjNode(ifNode.unkeep(), 1, "False").peephole();
 
         // 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
@@ -306,7 +295,7 @@ public class Parser {
 
     private ScopeNode jumpTo(ScopeNode toScope) {
         ScopeNode cur = _scope.dup();
-        ctrl(XCTRL); // Kill current scope
+        ctrl(new ConstantNode(Type.XCONTROL).peephole()); // 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._scopes.size() > _breakScope._scopes.size() )
@@ -342,8 +331,8 @@ public class Parser {
         // 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();
+        Node ifT = new ProjNode(ifNode.  keep(), 0, "True" ).peephole().keep();
+        Node ifF = new ProjNode(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
         int ndefs = _scope.nIns();
@@ -390,7 +379,7 @@ public class Parser {
     private Node parseReturn() {
         var expr = require(parseExpression(), ";");
         Node ret = STOP.addReturn(new ReturnNode(ctrl(), expr, _scope).peephole());
-        ctrl(XCTRL);            // Kill control
+        ctrl(new ConstantNode(Type.XCONTROL).peephole()); // Kill control
         return ret;
     }
 
@@ -585,7 +574,7 @@ public class Parser {
         if( _lexer.isNumber() ) return parseIntegerLiteral();
         if( match("(") ) return require(parseExpression(), ")");
         if( matchx("true" ) ) return new ConstantNode(TypeInteger.constant(1)).peephole();
-        if( matchx("false") ) return ZERO;
+        if( matchx("false") ) return new ConstantNode(TypeInteger.constant(0)).peephole();
         if( matchx("null" ) ) return new ConstantNode(TypeMemPtr.NULLPTR).peephole();
         if( matchx("new") ) {
             String structName = requireId();
@@ -603,11 +592,12 @@ public class Parser {
     /**
      * Return a NewNode but also generate instructions to initialize it.
      */
-    private Node newStruct(TypeStruct obj) {
+    private Node newStruct( TypeStruct obj ) {
         Node n = new NewNode(TypeMemPtr.make(obj), ctrl()).peephole().keep();
+        Node initValue = new ConstantNode(TypeInteger.constant(0)).peephole();
         int alias = _aliases.get(obj._name);
         for( Field field : obj._fields ) {
-            store(field._fname,alias,n,ZERO);
+            store(field._fname,alias,n,initValue);
             alias++;
         }
         return n.unkeep();
@@ -619,7 +609,7 @@ public class Parser {
 
     private void store(String name, int alias, Node ptr, Node val) {
         Node prior = mem().keep();
-        Node st = new StoreNode(name,alias,ctrl(),prior,ptr,val).peephole();
+        Node st = new StoreNode(name,alias,prior,ptr,val).peephole();
         mem(new MemMergeNode(prior,alias,st).peephole());
         prior.unkeep();
     }
@@ -759,16 +749,7 @@ public class Parser {
          * Return the next non-white-space character
          */
         private void skipWhiteSpace() {
-            while( true ) {
-                if( isWhiteSpace() ) _position++;
-                // Skip // to end of line
-                else if( _position+2 < _input.length &&
-                         _input[_position  ] == '/' &&
-                         _input[_position+1] == '/') {
-                    _position += 2;
-                    while( !isEOF() && _input[_position] != '\n' ) _position++;
-                } else break;
-            }
+            while (isWhiteSpace()) _position++;
         }
 
 
@@ -850,9 +831,8 @@ public class Parser {
             return new String(_input, start, --_position - start);
         }
 
-        //
         private boolean isPunctuation(char ch) {
-            return "=;[]<>()+-/*".indexOf(ch) != -1;
+            return "=;[]<>(){}+-/*!".indexOf(ch) != -1;
         }
 
         private String parsePunctuation() {
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/Utils.java b/chapter11/src/main/java/com/seaofnodes/simple/Utils.java
index f3ac25b1..4f2af769 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/Utils.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/Utils.java
@@ -55,4 +55,11 @@ public class Utils {
 
     // Fold a 64bit hash into 32 bits
     public static int fold( long x ) { return (int)((x>>32) ^ x); }
+
+    public static boolean eq(String s0, String s1) {
+        if( s0==s1 ) return true;
+        assert s0==s0.intern();
+        assert s1==s1.intern();
+        return false;
+    }
 }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/CFGNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/CFGNode.java
deleted file mode 100644
index ea67d17d..00000000
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/CFGNode.java
+++ /dev/null
@@ -1,95 +0,0 @@
-package com.seaofnodes.simple.node;
-
-import com.seaofnodes.simple.Parser;
-import com.seaofnodes.simple.type.*;
-import com.seaofnodes.simple.Utils;
-
-import java.util.BitSet;
-import java.util.HashSet;
-import java.util.HashMap;
-
-/** 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); }
-
-    @Override public boolean isCFG() { return true; }
-
-    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; }
-
-    // Should be exactly 1 tail from a block head
-    public CFGNode blockTail() {
-        assert blockHead();
-        for( Node n : _outputs )
-            if( n instanceof CFGNode cfg )
-                return cfg;
-        return null;
-    }
-
-    // ------------------------------------------------------------------------
-    /**
-     * 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 char _idepth;
-    public int idepth() { return _idepth!=0 ? _idepth : cacheIDepth(idom().idepth()+1); }
-    // Zero depth means uncached. Check before narrowing so overflow cannot wrap.
-    final int cacheIDepth(int depth) {
-        assert 0 <= depth && depth <= Character.MAX_VALUE : "Dominator depth exceeds 65535";
-        return _idepth = (char)depth;
-    }
-
-
-    // Return the immediate dominator of this Node and compute dom tree depth.
-    public CFGNode idom() { return cfg(0); }
-
-    // Return the LCA of two idoms
-    public CFGNode domLCA(CFGNode rhs) {
-        if( rhs==null ) return this;
-        CFGNode lhs = this;
-        while( lhs != rhs ) {
-            if( lhs==null || rhs==null ) return null;
-            int comp = lhs.idepth() - rhs.idepth();
-            if( comp >= 0 ) lhs = lhs.idom();
-            if( comp <= 0 ) rhs = rhs.idom();
-        }
-        return lhs;
-    }
-
-    // Loop nesting depth
-    public int _loopDepth;
-    public int loopDepth() { return _loopDepth==0 ? (_loopDepth = cfg(0).loopDepth()) : _loopDepth; }
-
-    // ------------------------------------------------------------------------
-    // Support routines for Global Code Motion
-
-    // Tik-tok recursion pattern.  This method is final, and every caller does
-    // this work.
-    public final void walkUnreach( BitSet visit, HashSet<CFGNode> unreach ) {
-        if( visit.get(_nid) ) return;
-        visit.set(_nid);
-        _walkUnreach(visit,unreach);
-        unreach.remove(this); // Since we reached here... Node was not unreachable
-    }
-
-    // Tik-tok recursion pattern; not-final; callers override this.
-    void _walkUnreach( BitSet visit, HashSet<CFGNode> unreach ) {
-        cfg(0).walkUnreach(visit,unreach);
-    }
-}
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/CProjNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/CProjNode.java
deleted file mode 100644
index ff5d1a76..00000000
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/CProjNode.java
+++ /dev/null
@@ -1,62 +0,0 @@
-package com.seaofnodes.simple.node;
-
-import com.seaofnodes.print.ExprPrinter;
-
-import com.seaofnodes.simple.Parser;
-import com.seaofnodes.simple.type.Type;
-import com.seaofnodes.simple.type.TypeMem;
-import com.seaofnodes.simple.type.TypeTuple;
-
-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;
-    }
-
-    @Override public String label() { return _label; }
-
-    @Override protected ExprPrinter<Node> _print1(ExprPrinter<Node> p) { return p.p(_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() instanceof IfNode iff ) {
-            if ( iff._type instanceof TypeTuple tt && tt._types[1 - _idx] == Type.XCONTROL )
-                return iff.in(0); // We become our input control
-
-            // Flip a negating if-test, to remove the not
-            if( iff.pred().addDep(this) instanceof NotNode not )
-                return new CProjNode(new IfNode(iff.ctrl(),not.in(1)).peephole(),1-_idx,_idx==0 ? "False" : "True");
-        }
-        return null;
-    }
-
-    @Override
-    public Node getBlockStart() {
-        return ctrl() instanceof IfNode ? this : ctrl().getBlockStart();
-    }
-    @Override
-    boolean eq( Node n ) { return _idx == ((CProjNode)n)._idx; }
-
-    @Override
-    int hash() { return _idx; }
-
-}
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/ConstantNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/ConstantNode.java
index 9ecd1152..426736ed 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/ConstantNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/ConstantNode.java
@@ -38,7 +38,6 @@ public class ConstantNode extends Node {
     }
 
     @Override public boolean isMultiTail() { return true; }
-    // The special forever-zero is pinned, all others can sink
 
     @Override
     public Type compute() { return _con; }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/IfNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/IfNode.java
index 70340f7f..45f695a5 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/IfNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/IfNode.java
@@ -5,10 +5,8 @@ import com.seaofnodes.simple.IterPeeps;
 import com.seaofnodes.simple.type.Type;
 import com.seaofnodes.simple.type.TypeInteger;
 import com.seaofnodes.simple.type.TypeTuple;
-import java.util.BitSet;
-import java.util.HashSet;
 
-public class IfNode extends CFGNode implements MultiNode {
+public class IfNode extends MultiNode {
 
     public IfNode(Node ctrl, Node pred) {
         super(ctrl, pred);
@@ -20,6 +18,7 @@ public class IfNode extends CFGNode implements MultiNode {
 
     @Override protected String format() { return "if( %1 )"; }
 
+    @Override public boolean isCFG() { return true; }
     @Override public boolean isMultiHead() { return true; }
 
     public Node ctrl() { return in(0); }
@@ -49,20 +48,11 @@ public class IfNode extends CFGNode implements MultiNode {
         // 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 ) {
+            for( Node 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 ProjNode prj ) {
                     setDef(1,new ConstantNode(TypeInteger.make(true,prj._idx==0?1:0)).peephole());
                     return this;
                 }
         return null;
     }
-
-    @Override void _walkUnreach( BitSet visit, HashSet<CFGNode> unreach ) {
-        for( Node proj : _outputs )
-            if( ((CProjNode)proj)._loopDepth == 0 )
-                unreach.add((CProjNode)proj);
-        super._walkUnreach(visit,unreach);
-    }
-
-    @Override public Node getBlockStart() { return ctrl().getBlockStart(); }
 }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/LoadNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/LoadNode.java
index 386009b4..9bf36459 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/LoadNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/LoadNode.java
@@ -23,7 +23,7 @@ public class LoadNode extends MemOpNode {
      * @param memPtr The ptr to the struct from where we load a field
      */
     public LoadNode(String name, int alias, Type glb, Node memSlice, Node memPtr) {
-        super(name, alias, null, memSlice, memPtr);
+        super(name, alias, memSlice, memPtr, null);
         _declaredType = glb;
     }
 
@@ -67,7 +67,7 @@ public class LoadNode extends MemOpNode {
         // Simple Load-after-Store on same address.
         if( mem() instanceof StoreNode st &&
             ptr() == st.ptr() && _alias==st._alias ) { // Must check same object
-            assert _name.equals(st._name); // Equiv class aliasing is perfect
+            assert Utils.eq(_name,st._name); // Equiv class aliasing is perfect
             return st.val();
         }
 
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/LoopNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/LoopNode.java
index 45549f1d..a0ba973e 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/LoopNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/LoopNode.java
@@ -1,17 +1,15 @@
 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;
-import java.util.HashSet;
 
 public class LoopNode extends RegionNode {
+
     public LoopNode( Node entry ) { super(null,entry,null); }
 
-    public CFGNode entry() { return cfg(1); }
-    public CFGNode back () { return cfg(2); }
+    Node entry() { return in(1); }
+    Node back () { return in(2); }
 
     @Override
     public String label() { return "Loop"; }
@@ -27,51 +25,7 @@ public class LoopNode extends RegionNode {
         return inProgress() ? null : super.idealize();
     }
 
-    // Bypass Region idom, same as the default idom() using use in(1) instead of in(0)
-    @Override public int idepth() { return _idepth!=0 ? _idepth : cacheIDepth(entry().idepth()+1); }
-    // Bypass Region idom, same as the default idom() using use in(1) instead of in(0)
-    @Override public CFGNode idom() { return entry(); }
-
-    @Override public int loopDepth() {
-        if( _loopDepth!=0 ) return _loopDepth; // Was already set
-        _loopDepth = entry()._loopDepth+1;     // Entry depth plus one
-        // One-time tag loop exits
-        for( CFGNode idom = back(); idom!=this; idom = idom.idom() ) {
-            // Walk idom in loop, setting depth
-            idom._loopDepth = _loopDepth;
-            // Loop exit hits the CProj before the If, instead of jumping from
-            // Region directly to If.
-            if( idom instanceof CProjNode proj ) {
-                assert proj.in(0) instanceof IfNode; // Loop exit test
-                // Find the loop exit CProj, and set loop_depth
-                for( Node use : proj.in(0)._outputs )
-                    if( use instanceof CProjNode proj2 && proj2 != idom )
-                        proj2._loopDepth = _loopDepth-1;
-            }
-        }
-        return _loopDepth;
-    }
-
-    // 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 void forceExit( 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 )
-                return;         // 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 phi )
-                iff.addDef(use);
-        CProjNode t = new CProjNode(iff,0,"True" );
-        CProjNode f = new CProjNode(iff,1,"False");
-        setDef(2,f);
-        stop.addDef(new ReturnNode(t,Parser.ZERO,null));
-    }
+    // Bypass Region idom, same as the default idom() using use entry in(1) instead of in(0)
+    @Override int idepth() { return _idepth!=0 ? _idepth : cacheIDepth(entry().idepth()+1); }
+    @Override Node idom() { return entry(); }
 }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/MemOpNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/MemOpNode.java
index 5a57a8c8..44304bcb 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/MemOpNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/MemOpNode.java
@@ -12,8 +12,8 @@ public abstract class MemOpNode extends Node {
     public final String _name;
     public final int _alias;
 
-    public MemOpNode(String name, int alias, Node... nodes) {
-        super(nodes);
+    public MemOpNode(String name, int alias, Node memSlice, Node memPtr, Node value) {
+        super(null, memSlice, memPtr, value);
         _name  = name;
         _alias = alias;
     }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/MultiNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/MultiNode.java
index 379e140d..2743bd19 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/MultiNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/MultiNode.java
@@ -1,10 +1,12 @@
 package com.seaofnodes.simple.node;
 
-public interface MultiNode extends OutNode {
+public abstract class MultiNode extends Node {
+
+    public MultiNode(Node... inputs) { super(inputs); }
 
     // Find a projection by index
-    default ProjNode proj( int idx ) {
-        for( Node out : outs() )
+    ProjNode proj( int idx ) {
+        for( Node out : _outputs )
             if( out instanceof ProjNode prj && prj._idx==idx )
                 return prj;
         return null;
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/NeverNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/NeverNode.java
deleted file mode 100644
index 6eb7fe63..00000000
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/NeverNode.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package com.seaofnodes.simple.node;
-
-import com.seaofnodes.print.ExprPrinter;
-
-import com.seaofnodes.simple.Parser;
-import com.seaofnodes.simple.type.TypeInteger;
-import com.seaofnodes.simple.type.Type;
-
-// "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 protected ExprPrinter<Node> _print1(ExprPrinter<Node> p) { return p.p("Never"); }
-
-    @Override public Type compute() { return TypeInteger.BOT; }
-
-    @Override public Node idealize() { return null; }
-}
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/NewNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/NewNode.java
index 74ba5184..857920bc 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/NewNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/NewNode.java
@@ -22,7 +22,6 @@ public class NewNode extends Node {
         return p.p("new ").p(_ptr._obj.str());
     }
 
-
     @Override
     public Type compute() { return _ptr; }
 
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/Node.java b/chapter11/src/main/java/com/seaofnodes/simple/node/Node.java
index 568c23cc..1d8e23f8 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/Node.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/Node.java
@@ -2,8 +2,9 @@ package com.seaofnodes.simple.node;
 
 import com.seaofnodes.print.BaseNode;
 
-import com.seaofnodes.simple.IRPrinter;
 import com.seaofnodes.simple.Parser;
+
+import com.seaofnodes.simple.IRPrinter;
 import com.seaofnodes.simple.IterPeeps;
 import com.seaofnodes.simple.Utils;
 import com.seaofnodes.simple.type.Type;
@@ -16,7 +17,7 @@ import java.util.function.Function;
  * The Node class provides common functionality used by all subtypes.
  * Subtypes of Node specialize by overriding methods.
  */
-public abstract class Node extends BaseNode<Node> implements OutNode, Cloneable {
+public abstract class Node extends BaseNode<Node> implements Cloneable {
 
     /**
      * Inputs to the node. These are use-def references to Nodes.
@@ -82,7 +83,6 @@ public abstract class Node extends BaseNode<Node> implements OutNode, Cloneable
      */
     public Node in(int i) { return _inputs.get(i); }
     public Node out(int i) { return _outputs.get(i); }
-    @Override public ArrayList<Node> outs() { return _outputs; }
 
     public int nIns() { return _inputs.size(); }
 
@@ -90,7 +90,7 @@ public abstract class Node extends BaseNode<Node> implements OutNode, Cloneable
 
     public boolean isUnused() { return nOuts() == 0; }
 
-    public CFGNode cfg0() { return (CFGNode)in(0); }
+    public boolean isMem() { return false; }
 
     /**
      * Change a <em>def</em> into a Node.  Keeps the edges correct, by removing
@@ -117,11 +117,11 @@ public abstract class Node extends BaseNode<Node> implements OutNode, Cloneable
         // 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
             old_def.delUse(this) ) // If we removed the last use, the old def is now dead
             old_def.kill();     // Kill old def
+        // Set the new_def over the old (killed) edge
+        _inputs.set(idx,new_def);
         moveDepsToWorklist();
         // Return self for easy flow-coding
         return new_def;
@@ -149,7 +149,7 @@ public abstract class Node extends BaseNode<Node> implements OutNode, Cloneable
      * @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) {
+    Node addDef(Node new_def) {
         unlock();
         // Add use->def edge
         _inputs.add(new_def);
@@ -268,8 +268,8 @@ public abstract class Node extends BaseNode<Node> implements OutNode, Cloneable
         Type old = setType(compute());
 
         // Replace constant computations from non-constants with a constant node
-        if( !(this instanceof ConstantNode) && !(this instanceof XCtrlNode) && _type.isHighOrConst() )
-            return (_type==Type.XCONTROL ? new XCtrlNode() : new ConstantNode(_type)).peepholeOpt();
+        if( !(this instanceof ConstantNode) && _type.isHighOrConst() )
+            return new ConstantNode(_type).peepholeOpt();
 
         // Global Value Numbering
         if( _hash==0 ) {
@@ -484,17 +484,6 @@ public abstract class Node extends BaseNode<Node> implements OutNode, Cloneable
     int hash() { return 0; }
 
     // ------------------------------------------------------------------------
-    //
-
-    /** Is this Node control-flow-graph related */
-
-    /** Is this Node Memory related */
-    public boolean isMem() { return false; }
-
-    /** Return block start from a isCFG() */
-    public Node getBlockStart() { return null; }
-
-    // ------------------------------------------------------------------------
     // Peephole utilities
 
     // Swap inputs without letting either input go dead during the swap.
@@ -522,6 +511,38 @@ public abstract class Node extends BaseNode<Node> implements OutNode, Cloneable
         return true;
     }
 
+    /**
+     * Immediate dominator tree depth, used to approximate a real IDOM depth
+     * 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 char _idepth;         // IDOM depth approx; Zero is unset; non-zero is cached legit
+
+    // Find the lowest common ancestor in the current dominator tree.
+    Node domLCA(Node rhs) {
+        if( rhs==null ) return this;
+        Node lhs = this;
+        while( lhs != rhs ) {
+            if( lhs==null || rhs==null ) return null;
+            int comp = lhs.idepth() - rhs.idepth();
+            if( comp >= 0 ) lhs = lhs.idom();
+            if( comp <= 0 ) rhs = rhs.idom();
+        }
+        return lhs;
+    }
+
+    int idepth() { return _idepth!=0 ? _idepth : cacheIDepth(idom().idepth()+1); }
+    // Zero depth means uncached. Check before narrowing so overflow cannot wrap.
+    final int cacheIDepth(int depth) {
+        assert 0 <= depth && depth <= Character.MAX_VALUE : "Dominator depth exceeds 65535";
+        return _idepth = (char)depth;
+    }
+
+    // Return the immediate dominator of this Node.
+    Node idom() { return in(0); }
+
     // 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.
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/OutNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/OutNode.java
deleted file mode 100644
index 7e531145..00000000
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/OutNode.java
+++ /dev/null
@@ -1,7 +0,0 @@
-package com.seaofnodes.simple.node;
-
-import java.util.ArrayList;
-
-public interface OutNode {
-    ArrayList<Node> outs();
-}
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/PhiNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/PhiNode.java
index 8f3cda9e..6995cc2f 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/PhiNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/PhiNode.java
@@ -32,9 +32,10 @@ public class PhiNode extends Node {
         return p.unchar(',').close();
     }
 
-    public CFGNode region() { return (CFGNode)in(0); }
+    Node region() { return in(0); }
     @Override public boolean isMultiTail() { return true; }
-    @Override public boolean isMem() { return _declaredType instanceof TypeMem; }
+    @Override
+    public boolean isMem() { return _declaredType instanceof TypeMem; }
 
     @Override
     public Type compute() {
@@ -84,9 +85,9 @@ public class PhiNode extends Node {
                 Node val = in(3-nullx);
                 if( region().idom() 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)region().in(nullx);
+                    Node idom = region().in(nullx);
                     while( idom.in(0) != iff ) idom = idom.idom();
-                    if( idom instanceof CProjNode proj && proj._idx==1 )
+                    if( idom instanceof ProjNode proj && proj._idx==1 )
                         return val;
                 }
             }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/ProjNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/ProjNode.java
index e82c69b3..a2632110 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/ProjNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/ProjNode.java
@@ -15,7 +15,7 @@ public class ProjNode extends Node {
     // Debugging label
     public final String _label;
 
-    public ProjNode(Node ctrl, int idx, String label) {
+    public ProjNode(MultiNode ctrl, int idx, String label) {
         super(ctrl);
         _idx = idx;
         _label = label;
@@ -27,16 +27,30 @@ public class ProjNode extends Node {
     @Override
     protected ExprPrinter<Node> _print1(ExprPrinter<Node> p) { return p.p(_label); }
 
+    @Override public boolean isCFG() { return _idx==0 || ctrl() instanceof IfNode; }
     @Override public boolean isMultiTail() { return in(0).isMultiHead(); }
     @Override public boolean isMem() { return _type instanceof TypeMem; }
 
+    public MultiNode ctrl() { return (MultiNode)in(0); }
+
     @Override
     public Type compute() {
         Type t = in(0)._type;
         return t instanceof TypeTuple tt ? tt._types[_idx] : Type.BOTTOM;
     }
 
-    @Override public Node idealize() { return null; }
+    @Override
+    public Node idealize() {
+        if ( ctrl() instanceof IfNode iff ) {
+            if ( iff._type instanceof TypeTuple tt && tt._types[1 - _idx] == Type.XCONTROL )
+                return iff.in(0); // We become our input control
+
+            // Flip a negating if-test, to remove the not
+            if( iff.pred().addDep(this) instanceof NotNode not )
+                return new ProjNode((MultiNode)new IfNode(iff.ctrl(),not.in(1)).peephole(),1-_idx,_idx==0 ? "False" : "True");
+        }
+        return null;
+    }
 
     @Override
     boolean eq( Node n ) { return _idx == ((ProjNode)n)._idx; }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/RegionNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/RegionNode.java
index f0808410..8b52494a 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/RegionNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/RegionNode.java
@@ -3,15 +3,13 @@ package com.seaofnodes.simple.node;
 import com.seaofnodes.print.ExprPrinter;
 
 import com.seaofnodes.simple.IterPeeps;
-import com.seaofnodes.simple.Parser;
 import com.seaofnodes.simple.Utils;
 import com.seaofnodes.simple.type.Type;
+
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.BitSet;
-import java.util.HashSet;
 
-public class RegionNode extends CFGNode {
+public class RegionNode extends Node {
 
     public RegionNode(Node... nodes) { super(nodes); }
 
@@ -22,8 +20,8 @@ public class RegionNode extends CFGNode {
         return p.p(label()).p(_nid);
     }
 
+    @Override public boolean isCFG() { return true; }
     @Override public boolean isMultiHead() { return true; }
-    @Override public boolean blockHead() { return true; }
 
     @Override
     public Type compute() {
@@ -59,7 +57,7 @@ public class RegionNode extends CFGNode {
                         IterPeeps.addAll(phi._outputs);
                     }
             }
-            return isDead() ? Parser.XCTRL : delDef(path);
+            return isDead() ? new ConstantNode(Type.XCONTROL) : delDef(path);
         }
         // If down to a single input, become that input
         if( nIns()==2 && !hasPhi() )
@@ -91,30 +89,23 @@ public class RegionNode extends CFGNode {
     }
 
     // Immediate dominator of Region is a little more complicated.
-    @Override public int idepth() {
+    @Override int idepth() {
         if( _idepth!=0 ) return _idepth;
         int depth=0;
         for( Node n : _inputs )
             if( n!=null )
-                depth = Math.max(depth,((CFGNode)n).idepth()+1);
+                depth = Math.max(depth,n.idepth()+1);
         return cacheIDepth(depth);
     }
 
-    @Override public CFGNode idom() {
-        CFGNode lca = null;
+    @Override Node idom() {
+        Node lca = null;
         // Recompute from predecessors: CFG edits can change the dominator.
         for( int i=1; i<nIns(); i++ )
-            lca = cfg(i).domLCA(lca);
+            lca = in(i).domLCA(lca);
         return lca;
     }
 
-    @Override void _walkUnreach( BitSet visit, HashSet<CFGNode> unreach ) {
-        for( int i=1; i<nIns(); i++ )
-            cfg(i).walkUnreach(visit,unreach);
-    }
-
-    @Override public int loopDepth() { return _loopDepth==0 ? (_loopDepth = cfg(1).loopDepth()) : _loopDepth; }
-
     // True if last input is null
     public final boolean inProgress() {
         return nIns()>1 && in(nIns()-1) == null;
@@ -124,6 +115,4 @@ public class RegionNode extends CFGNode {
     @Override boolean eq( Node n ) {
         return !inProgress();
     }
-
-    @Override public Node getBlockStart() { return this; }
 }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/ReturnNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/ReturnNode.java
index 161cc7d6..ef4ddb3a 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/ReturnNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/ReturnNode.java
@@ -6,11 +6,10 @@ import com.seaofnodes.simple.type.*;
 
 
 /** Keeps all preceding memory effects and the return value alive: {ctrl, $mem, value}. */
-public class ReturnNode extends CFGNode {
+public class ReturnNode extends Node {
 
     public ReturnNode(Node ctrl, Node data, ScopeNode scope) {
-        // A synthetic never-taken loop exit has no source scope.
-        super(ctrl, scope == null ? null : scope.lookup("$mem"), data);
+        super(ctrl, scope.lookup("$mem"), data);
     }
 
     public Node ctrl() { return in(0); }
@@ -27,6 +26,8 @@ public class ReturnNode extends CFGNode {
         return p.p(";");
     }
 
+    @Override public boolean isCFG() { return true; }
+
     @Override
     public Type compute() {
         // Return exposes the complete memory state.
@@ -39,6 +40,4 @@ public class ReturnNode extends CFGNode {
             return ctrl();
         return null;
     }
-
-    @Override public Node getBlockStart() { return ctrl().getBlockStart(); }
 }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/StartNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/StartNode.java
index c1b57915..3404f111 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/StartNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/StartNode.java
@@ -3,13 +3,10 @@ package com.seaofnodes.simple.node;
 import com.seaofnodes.print.ExprPrinter;
 
 import com.seaofnodes.simple.type.*;
-import java.util.BitSet;
-import java.util.HashSet;
 
-/** Start supplies control, whole memory, and the argument, in that order. */
-public class StartNode extends CFGNode implements MultiNode {
-
-    private final TypeTuple _args;
+/** The entry tuple: control, initial whole-memory state, and argument. */
+public class StartNode extends MultiNode {
+    final TypeTuple _args;
 
     public StartNode(Type[] args) {
         super();
@@ -23,8 +20,8 @@ public class StartNode extends CFGNode implements MultiNode {
         return p.p(label());
     }
 
+    @Override public boolean isCFG() { return true; }
     @Override public boolean isMultiHead() { return true; }
-    @Override public boolean blockHead() { return true; }
 
     @Override
     public TypeTuple compute() { return _args; }
@@ -33,12 +30,6 @@ public class StartNode extends CFGNode implements MultiNode {
     public Node idealize() { return null; }
 
     // No immediate dominator, and idepth==0
-    @Override public int idepth() { return 0; }
-    @Override public CFGNode idom() { return null; }
-
-    @Override void _walkUnreach( BitSet visit, HashSet<CFGNode> unreach ) { }
-
-    @Override public int loopDepth() { return (_loopDepth=1); }
-
-    @Override public Node getBlockStart() { return this; }
+    @Override int idepth() { return 0; }
+    @Override Node idom() { return null; }
 }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/StopNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/StopNode.java
index 46cf51da..4b4e9615 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/StopNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/StopNode.java
@@ -8,7 +8,7 @@ import com.seaofnodes.simple.type.Type;
 import com.seaofnodes.simple.IterPeeps;
 
 
-public class StopNode extends CFGNode {
+public class StopNode extends Node {
 
     public final String _src;
 
@@ -31,7 +31,7 @@ public class StopNode extends CFGNode {
         return p.p("]");
     }
 
-    @Override public boolean blockHead() { return true; }
+    @Override public boolean isCFG() { return true; }
 
     // If a single Return, return it.
     // Otherwise, null because ambiguous.
@@ -54,17 +54,7 @@ public class StopNode extends CFGNode {
         return null;
     }
 
-    @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 cacheIDepth(d);
-    }
-    @Override public CFGNode idom() { return null; }
-
-    @Override public int loopDepth() { return (_loopDepth=1); }
+    @Override public Node idom() { return null; }
 
     public Node addReturn(Node node) {
         return addDef(node);
@@ -82,6 +72,4 @@ public class StopNode extends CFGNode {
         if( obs != null ) obs.phase("TypeCheck");
         return this;
     }
-
-    @Override public Node getBlockStart() { return this; }
 }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/StoreNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/StoreNode.java
index f61afe78..026d5c50 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/StoreNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/StoreNode.java
@@ -19,8 +19,8 @@ public class StoreNode extends MemOpNode {
      * @param memPtr The ptr to the struct where we will store a value
      * @param value Value to be stored
      */
-    public StoreNode(String name, int alias, Node ctrl, Node memSlice, Node memPtr, Node value) {
-        super(name, alias, ctrl, memSlice, memPtr, value);
+    public StoreNode(String name, int alias, Node memSlice, Node memPtr, Node value) {
+        super(name, alias, memSlice, memPtr, value);
     }
 
     @Override
@@ -53,7 +53,7 @@ public class StoreNode extends MemOpNode {
             // Must have exactly one use of "this" or you get weird
             // non-serializable memory effects in the worse case.
             st.checkNoUseBeyond(this) ) {
-            assert _name.equals(st._name); // Equiv class aliasing is perfect
+            assert Utils.eq(_name,st._name); // Equiv class aliasing is perfect
             setDef(1,st.mem());
             return this;
         }
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/SubNode.java
index 7b4cff0b..6fa87a07 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/SubNode.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/node/SubNode.java
@@ -1,7 +1,6 @@
 package com.seaofnodes.simple.node;
 
 
-import com.seaofnodes.simple.Parser;
 import com.seaofnodes.simple.type.Type;
 import com.seaofnodes.simple.type.TypeInteger;
 
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/node/XCtrlNode.java b/chapter11/src/main/java/com/seaofnodes/simple/node/XCtrlNode.java
deleted file mode 100644
index 056dfba1..00000000
--- a/chapter11/src/main/java/com/seaofnodes/simple/node/XCtrlNode.java
+++ /dev/null
@@ -1,14 +0,0 @@
-package com.seaofnodes.simple.node;
-
-import com.seaofnodes.print.ExprPrinter;
-
-import com.seaofnodes.simple.Parser;
-import com.seaofnodes.simple.type.Type;
-
-public class XCtrlNode extends CFGNode {
-    public XCtrlNode( ) { super(Parser.START); }
-    @Override public String label() { return "Xctrl"; }
-    @Override protected ExprPrinter<Node> _print1(ExprPrinter<Node> p) { return p.p("Xctrl"); }
-    @Override  public Type compute() { return Type.XCONTROL; }
-    @Override public Node idealize() { return null; }
-}
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java b/chapter11/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java
index 89ef99bd..92d970d8 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java
@@ -6,13 +6,13 @@ import com.seaofnodes.simple.node.*;
 import com.seaofnodes.simple.node.Node;
 import com.seaofnodes.simple.type.TypeMem;
 
-/** Chapter 11's view of the IR; browser, transport and layout are shared. */
+/** Chapter 10's view of the IR; browser, transport and layout are shared. */
 public class SimpleGraphAdapter extends GraphAdapter<Node> {
 
     @Override protected String[] edgeNames(Node n) {
         return n instanceof ScopeNode scope && n.nIns()!=0 ? scope.reverseNames() : null;
     }
-    @Override protected int projectionIndex(Node n) { return n instanceof ProjNode p ? p._idx : n instanceof CProjNode p ? p._idx : -1; }
+    @Override protected int projectionIndex(Node n) { return n instanceof ProjNode p ? p._idx : -1; }
 
     @Override protected Kind kind(Node n) {
         if( n instanceof StopNode ) return Kind.STOP;
@@ -25,9 +25,9 @@ public class SimpleGraphAdapter extends GraphAdapter<Node> {
     }
 
     @Override protected Role role(Node n, int i) {
-        if( n instanceof ScopeNode || n instanceof ConstantNode || n instanceof XCtrlNode ) return Role.ASSOC;
+        if( n instanceof ScopeNode || n instanceof ConstantNode ) return Role.ASSOC;
         if( n instanceof PhiNode ) return i == 0 ? Role.ASSOC : isMem(n) ? Role.MEM : Role.DATA;
-        if( n instanceof ProjNode || n instanceof CProjNode ) return n.isCFG() ? Role.CTRL : isMem(n) ? Role.MEM : Role.DATA;
+        if( n instanceof ProjNode ) return n.isCFG() ? Role.CTRL : isMem(n) ? Role.MEM : Role.DATA;
         if( n instanceof RegionNode && i == 0 ) return Role.ASSOC;
         if( i == 0 || n instanceof RegionNode || n instanceof StopNode ) return Role.CTRL;
         if( i == 1 && (n instanceof MemOpNode || n instanceof ReturnNode) ) return Role.MEM;
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/type/Field.java b/chapter11/src/main/java/com/seaofnodes/simple/type/Field.java
index b50a4fa6..cdc58215 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/type/Field.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/type/Field.java
@@ -20,7 +20,6 @@ public class Field extends Type {
         _fname = fname;
         _type  = type;
     }
-    // Make with existing alias
     public static Field make( String fname, Type type ) {
         return new Field(fname,type).intern();
     }
@@ -47,7 +46,7 @@ public class Field extends Type {
 
     boolean eq(Type t) {
         Field f = (Field)t;
-        return _fname.equals(f._fname) && _type==f._type;
+        return Utils.eq(_fname,f._fname) && _type==f._type;
     }
 
 
diff --git a/chapter11/src/main/java/com/seaofnodes/simple/type/TypeTuple.java b/chapter11/src/main/java/com/seaofnodes/simple/type/TypeTuple.java
index ec7390ca..0aa019a7 100644
--- a/chapter11/src/main/java/com/seaofnodes/simple/type/TypeTuple.java
+++ b/chapter11/src/main/java/com/seaofnodes/simple/type/TypeTuple.java
@@ -58,7 +58,8 @@ public class TypeTuple extends Type {
         for( Type t : _types )
             t.typeName(sb).append(",");
         sb.setLength(sb.length()-1);
-        return sb.append("]");
+        sb.append("]");
+        return sb;
     }
 
     public static final TypeTuple IF_BOTH    = make(new Type[]{Type. CONTROL,Type. CONTROL});
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter01Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter01Test.java
index c10dc510..89882b2f 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter01Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter01Test.java
@@ -15,7 +15,7 @@ public class Chapter01Test {
         StartNode start = Parser.START;
         ReturnNode ret = (ReturnNode)stop.in(0);
 
-        assertTrue(ret.ctrl() instanceof CProjNode);
+        assertTrue(ret.ctrl() instanceof ProjNode);
         Node expr = ret.expr();
         if( expr instanceof ConstantNode con ) {
             assertEquals(start,con.in(0));
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter04Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter04Test.java
index 14d31245..edc62f50 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter04Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter04Test.java
@@ -83,7 +83,7 @@ public class Chapter04Test {
         Parser parser = new Parser("return arg; ");
         StopNode stop = parser.parse();
         ReturnNode ret = stop.ret();
-        assertTrue(ret.in(0) instanceof CProjNode);
+        assertTrue(ret.in(0) instanceof ProjNode);
         assertTrue(ret.in(1) instanceof ProjNode);
         assertEquals(1, ((ProjNode)ret.in(1))._idx);
         assertTrue(ret.in(2) instanceof ProjNode);
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter05Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter05Test.java
index 7beeb4d9..cf7bd6cf 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter05Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter05Test.java
@@ -22,7 +22,7 @@ else {
 
 return a;""");
         StopNode ret = parser.parse().iterate();
-        assertEquals("return Phi(Region21,(arg+2),(arg-3));", ret.toString());
+        assertEquals("return Phi(Region19,(arg+2),(arg-3));", ret.toString());
     }
 
     @Test
@@ -37,7 +37,7 @@ if (arg == 1) {
 }
 return c;""", TypeInteger.BOT);
         StopNode ret = parser.parse().iterate();
-        assertEquals("return Phi(Region19,4,3);", ret.toString());
+        assertEquals("return Phi(Region17,4,3);", ret.toString());
     }
 
     @Test
@@ -65,7 +65,7 @@ else
     b=a+1;
 return a+b;""");
         StopNode ret = parser.parse().iterate();
-        assertEquals("return ((arg*2)+Phi(Region24,2,3));", ret.toString());
+        assertEquals("return ((arg*2)+Phi(Region22,2,3));", ret.toString());
     }
 
     @Test
@@ -80,7 +80,7 @@ else
     a=b+1;
 return a+b;""");
         StopNode ret = parser.parse().iterate();
-        assertEquals("return ((Phi(Region35,(arg*2),arg)+arg)+Phi(Region,4,5));", ret.toString());
+        assertEquals("return ((Phi(Region33,(arg*2),arg)+arg)+Phi(Region,4,5));", ret.toString());
     }
 
     @Test
@@ -100,7 +100,7 @@ else
 return a;
 """, TypeInteger.BOT);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region39,Phi(Region25,2,3),Phi(Region37,4,5));", stop.toString());
+        assertEquals("return Phi(Region37,Phi(Region23,2,3),Phi(Region35,4,5));", stop.toString());
     }
 
     @Test
@@ -116,7 +116,7 @@ if( arg==0 )
 return arg+a+b;
 """, TypeInteger.BOT);
         StopNode stop = parser.parse();
-        assertEquals("return ((arg+Phi(Region16,1,0))+Phi(Region31,2,0));", stop.toString());
+        assertEquals("return ((arg+Phi(Region14,1,0))+Phi(Region29,2,0));", stop.toString());
     }
 
     @Test
@@ -130,7 +130,7 @@ if( arg==1 )
 }
 return a;""");
         StopNode ret = parser.parse().iterate();
-        assertEquals("return (arg==Phi(Region19,3,2));", ret.toString());
+        assertEquals("return (arg==Phi(Region17,3,2));", ret.toString());
     }
 
     @Test
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter06Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter06Test.java
index df0f2848..920e26e3 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter06Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter06Test.java
@@ -17,7 +17,7 @@ return 1;
 """);
         StopNode stop = parser.parse().iterate();
         assertEquals("return 2;", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -30,7 +30,7 @@ if (arg)
 return (arg < a) < 3;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return ((arg<Phi(Region15,2,1))<3);", stop.toString());
+        assertEquals("return ((arg<Phi(Region13,2,1))<3);", stop.toString());
     }
 
     @Test
@@ -46,7 +46,7 @@ return a;
 """);
         StopNode stop = parser.parse().iterate();
         assertEquals("return 2;", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -65,7 +65,7 @@ else
     b=5;
 return b;""", TypeInteger.BOT);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region40,42,5);", stop.toString());
+        assertEquals("return Phi(Region38,42,5);", stop.toString());
     }
 
     @Test
@@ -84,7 +84,7 @@ else
     b=5;
 return b;""", TypeInteger.BOT);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region33,2,5);", stop.toString());
+        assertEquals("return Phi(Region31,2,5);", stop.toString());
     }
 
     @Test
@@ -144,7 +144,7 @@ else
 return a;
 """, TypeInteger.BOT);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region44,3,Phi(Region42,4,5));", stop.toString());
+        assertEquals("return Phi(Region42,3,Phi(Region40,4,5));", stop.toString());
     }
 
     @Test
@@ -200,7 +200,7 @@ if( arg ) {
 return a+b;
 """);
         StopNode ret = parser.parse().iterate();
-        assertEquals("return Phi(Region27,4,1);", ret.toString());
+        assertEquals("return Phi(Region25,4,1);", ret.toString());
     }
 
 
@@ -251,7 +251,7 @@ if( arg ) {
 return a+b+c;
 """);
         StopNode ret = parser.parse().iterate();
-        assertEquals("return (Phi(Region39,Phi(Region26,2,3),0)+Phi(Region,3,1));", ret.toString());
+        assertEquals("return (Phi(Region37,Phi(Region24,2,3),0)+Phi(Region,3,1));", ret.toString());
     }
 
 
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter07Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter07Test.java
index 222982e7..ff0ca599 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter07Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter07Test.java
@@ -18,8 +18,8 @@ public class Chapter07Test {
                 return arg;
                 """);
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop9,arg,(Phi_arg+1));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop7,arg,(Phi_arg+1));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -35,7 +35,7 @@ if(arg){}else{
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region27,1,Phi(Loop16,1,(Phi_a+1)));", stop.toString());
+        assertEquals("return Phi(Region25,1,Phi(Loop14,1,(Phi_a+1)));", stop.toString());
     }
 
     @Test
@@ -55,7 +55,7 @@ while(i < arg) {
 return sum;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,0,Phi(Loop23,Phi_sum,(Phi_sum+Phi(Loop,0,(Phi_j+1)))));", stop.toString());
+        assertEquals("return Phi(Loop9,0,Phi(Loop21,Phi_sum,(Phi_sum+Phi(Loop,0,(Phi_j+1)))));", stop.toString());
     }
 
     @Test
@@ -71,8 +71,8 @@ while(a < 10) {
 return b;
 """);
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop11,2,Phi(Region30,Phi_b,4));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop9,2,Phi(Region28,Phi_b,4));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -90,8 +90,8 @@ while(a < 10) {
 return b;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,2,(Phi(Region30,Phi_b,4)+1));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop9,2,(Phi(Region28,Phi_b,4)+1));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
 
@@ -107,8 +107,8 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop10,1,(Phi_a+3));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop8,1,(Phi_a+3));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -123,8 +123,8 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop10,1,(Phi_a+3));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop8,1,(Phi_a+3));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -136,8 +136,8 @@ while(arg) a = 2;
 return a;
 """);
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop10,1,2);", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop8,1,2);", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -149,8 +149,8 @@ while(arg) a = 2;
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop10,1,2);", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop8,1,2);", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -165,8 +165,8 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop10,1,(Phi_a+3));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop8,1,(Phi_a+3));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -181,8 +181,8 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop10,1,(Phi_a+3));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop8,1,(Phi_a+3));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -198,8 +198,8 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse();
-        assertEquals("return Phi(Loop11,1,(Phi_a+3));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop9,1,(Phi_a+3));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -215,8 +215,8 @@ while(a < 10) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,1,(Phi_a+3));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop9,1,(Phi_a+3));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
 }
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter08Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter08Test.java
index 8fcb29a0..4fa08bd9 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter08Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter08Test.java
@@ -24,7 +24,7 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region37,Phi(Region27,Phi(Loop9,arg,(Phi_arg+1)),Add),Add);", stop.toString());
+        assertEquals("return Phi(Region37,Phi(Region26,Phi(Loop7,arg,(Phi_arg+1)),Add),Add);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof RegionNode);
         Assert.assertEquals(5L, Evaluator.evaluate(stop, 1));
         Assert.assertEquals(10L, Evaluator.evaluate(stop, 6));
@@ -47,8 +47,8 @@ while(arg < 10) {
 return a;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop10,1,Phi(Region42,Phi_a,(Phi_a+1)));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop8,1,Phi(Region43,Phi_a,(Phi_a+1)));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
 
@@ -66,7 +66,7 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region35,Phi(Loop9,arg,(Phi_arg+1)),Add);", stop.toString());
+        assertEquals("return Phi(Region35,Phi(Loop7,arg,(Phi_arg+1)),Add);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof RegionNode);
     }
 
@@ -82,7 +82,7 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region27,Phi(Loop9,arg,(Phi_arg+1)),Add);", stop.toString());
+        assertEquals("return Phi(Region26,Phi(Loop7,arg,(Phi_arg+1)),Add);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof RegionNode);
     }
 
@@ -101,8 +101,8 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop9,arg,(Phi_arg+1));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop7,arg,(Phi_arg+1));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
 
@@ -118,8 +118,8 @@ while(arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop9,arg,(Phi_arg+1));", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode);
+        assertEquals("return Phi(Loop7,arg,(Phi_arg+1));", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode);
     }
 
     @Test
@@ -186,7 +186,7 @@ while(arg < 10) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region30,Phi(Loop10,1,(Phi_a+1)),Add);", stop.toString());
+        assertEquals("return Phi(Region29,Phi(Loop8,1,(Phi_a+1)),Add);", stop.toString());
         assertTrue(stop.ret().ctrl() instanceof RegionNode);
     }
 
@@ -202,8 +202,8 @@ while(1) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return (Phi(Loop10,1,Add)+1);", stop.toString());
-        assertTrue(stop.ret().ctrl() instanceof CProjNode prj && prj._idx==1 );
+        assertEquals("return (Phi(Loop8,1,Add)+1);", stop.toString());
+        assertTrue(stop.ret().ctrl() instanceof ProjNode prj && prj._idx==1 );
     }
 
 }
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter09Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter09Test.java
index 7af2fa3d..1b1920e8 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter09Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter09Test.java
@@ -70,7 +70,7 @@ while (arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop10,arg,(Phi_arg+2));", stop.toString());
+        assertEquals("return Phi(Loop8,arg,(Phi_arg+2));", stop.toString());
         Assert.assertEquals(11L, Evaluator.evaluate(stop, 1));
     }
 
@@ -87,7 +87,7 @@ while (arg < 10) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop11,arg,(Phi_arg+4));", stop.toString());
+        assertEquals("return Phi(Loop9,arg,(Phi_arg+4));", stop.toString());
         Assert.assertEquals(13L, Evaluator.evaluate(stop, 1));
     }
 
@@ -116,7 +116,7 @@ while (arg) {
 return arg;
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop17,arg,(Phi_arg+1));", stop.toString());
+        assertEquals("return Phi(Loop15,arg,(Phi_arg+1));", stop.toString());
     }
 
     @Test
@@ -134,14 +134,14 @@ while(v1+arg) {
 }
                 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("Stop[ return 0; return 0; ]", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
     public void testWhile0() {
         Parser parser = new Parser("while(0) continue; if(0) arg=0;");
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
@@ -153,7 +153,7 @@ if(0) while(0) {
 }
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
 
@@ -186,7 +186,7 @@ while(arg) {
 return a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop12,0,(-(Phi_a+3)));", stop.toString());
+        assertEquals("return Phi(Loop10,0,(-(Phi_a+3)));", stop.toString());
     }
 
     @Test
@@ -200,7 +200,7 @@ int v0=0!=0<-0;
 return -0+0+0;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
 
@@ -215,7 +215,7 @@ return -0+0+0;
     public void testFuzz3() {
         Parser parser = new Parser("int v0=0; while(0==69) while(v0) return 0;");
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
@@ -227,7 +227,7 @@ while(1) {
 }
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
@@ -249,19 +249,18 @@ while(1) {
 return 0!=0;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
     public void testFuzz6() {
-        Parser parser = new Parser(
-"""
+        Parser parser = new Parser("""
 int v0=0;
 while(0==1) while(v0)
         v0=1+v0;
-""");
+                                   """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
@@ -277,14 +276,14 @@ while(1)
 return v1+v0;
                                    """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
     public void testFuzz8() {
         Parser parser = new Parser("while(arg) arg = arg - 1;  return arg;");
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop9,arg,(Phi_arg-1));", stop.toString());
+        assertEquals("return Phi(Loop7,arg,(Phi_arg-1));", stop.toString());
     }
 
     @Test
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter10Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter10Test.java
index 0da695a0..8bf1debe 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter10Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter10Test.java
@@ -2,11 +2,15 @@ package com.seaofnodes.simple;
 
 import com.seaofnodes.simple.node.Node;
 import com.seaofnodes.simple.node.StopNode;
+import com.seaofnodes.simple.type.*;
 import com.seaofnodes.simple.node.LoadNode;
 import com.seaofnodes.simple.node.StoreNode;
 import com.seaofnodes.simple.evaluator.Evaluator;
 import java.util.BitSet;
 import org.junit.Test;
+
+import java.util.Arrays;
+
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.fail;
 
@@ -165,7 +169,7 @@ while (arg) {
 return bar.a;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop12,0,(Phi_a+2));", stop.toString());
+        assertEquals("return Phi(Loop11,0,(Phi_a+2));", stop.toString());
     }
 
     @Test
@@ -217,7 +221,7 @@ if( bar ) bar.a = 1;
 return bar;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region17,null,new Bar);", stop.toString());
+        assertEquals("return Phi(Region16,null,new Bar);", stop.toString());
     }
 
     @Test
@@ -233,7 +237,7 @@ else bar.a = 1;
 return rez;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region35,4,3);", stop.toString());
+        assertEquals("return Phi(Region34,4,3);", stop.toString());
     }
 
     @Test
@@ -250,8 +254,7 @@ while(arg) {
 return ret;
 """);
         try { parser.parse().iterate(); fail(); }
-        catch( Exception e ) {
-            assertEquals("Might be null accessing 'v0'", e.getMessage()); }
+        catch( Exception e ) { assertEquals("Might be null accessing 'v0'", e.getMessage()); }
     }
 
     @Test
@@ -287,7 +290,7 @@ while( i.x < i.len ) {
 return sum;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop17,0,(Phi(Loop,0,(Phi_x+1))+Phi_sum));", stop.toString());
+        assertEquals("return Phi(Loop16,0,(Phi(Loop,0,(Phi_x+1))+Phi_sum));", stop.toString());
     }
 
 
@@ -303,12 +306,11 @@ while(arg) {
     v0.v0 = arg;
     arg = arg-1;
     if (arg==5) ret=v0;
-
 }
 return ret;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop12,new s0,Phi(Region34,new s0,Phi_ret));", stop.toString());
+        assertEquals("return Phi(Loop11,new s0,Phi(Region34,new s0,Phi_ret));", stop.toString());
     }
 
     @Test
@@ -321,7 +323,6 @@ while(arg) {
     v0.v0 = arg;
     arg = arg-1;
     if (arg==5) ret=v0;
-
 }
 return ret;
 """);
@@ -343,7 +344,7 @@ while(arg < 10) {
 return ret;
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop12,new s0,Phi(Region32,new s0,Phi_ret));", stop.toString());
+        assertEquals("return Phi(Loop11,new s0,Phi(Region32,new s0,Phi_ret));", stop.toString());
     }
 
     @Test
@@ -373,7 +374,7 @@ if(0) {
 }
    """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
@@ -447,7 +448,7 @@ while(0) {}
 }
 """);
         StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
+        assertEquals("Stop[ ]", stop.toString());
     }
 
     @Test
@@ -461,6 +462,7 @@ return 0;
         assertEquals("return 0;", stop.toString());
     }
 
+
     @Test public void testReadBeforeStores() {
         var stop = new Parser("""
             struct S { int x; int y; }
@@ -547,8 +549,8 @@ return 0;
             if (arg) s.x=arg+1; else s.x=arg+2;
             return s;
             """).parse().iterate();
-        // These chapters still bind struct Stores to branch control.
-        assertEquals(3,countMemoryNodes(stop,StoreNode.class,new BitSet()));
+        // The initializing slice also remains live as the aggregate default.
+        assertEquals(2,countMemoryNodes(stop,StoreNode.class,new BitSet()));
         assertEquals(2L,((Evaluator.Obj)Evaluator.evaluate(stop,0)).fields()[0]);
         assertEquals(4L,((Evaluator.Obj)Evaluator.evaluate(stop,3)).fields()[0]);
     }
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter10bTest.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter10bTest.java
deleted file mode 100644
index 6f094cfb..00000000
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter10bTest.java
+++ /dev/null
@@ -1,64 +0,0 @@
-package com.seaofnodes.simple;
-
-import com.seaofnodes.simple.node.*;
-import com.seaofnodes.simple.evaluator.Evaluator;
-import org.junit.Test;
-import static org.junit.Assert.*;
-
-public class Chapter10bTest {
-    @Test public void testIndependentField() {
-        var stop = new Parser("""
-            struct S { int x; int y; }
-            S s = new S;
-            s.x = 42;
-            while (arg > 0) { s.y = s.y + arg; arg = arg - 1; }
-            return s.x;
-            """).parse().iterate();
-        assertEquals("return 42;",stop.toString());
-        assertEquals(42L,Evaluator.evaluate(stop,5));
-        assertNull(stop.walk(n -> n instanceof LoadNode ? n : null));
-    }
-
-    @Test public void testParallelMemoryPhis() {
-        var stop = new Parser("""
-            struct S { int x; int y; int z; }
-            S a = new S; S b = new S;
-            S p = a; if (arg) p = b;
-            while (arg > 0) {
-                a.x = p.x + arg;
-                a.y = p.y + 2;
-                a.z = p.z + 3;
-                arg = arg - 1;
-            }
-            return a;
-            """).parse().iterate();
-        int[] phis = {0};
-        stop.walk(n -> {
-            if (n instanceof MemPhiNode) phis[0]++;
-            if (n instanceof MemMergeNode m && m.in(1) instanceof BulkMemPhiNode b)
-                for(int a=b._aliases.nextSetBit(0); a>=0; a=b._aliases.nextSetBit(a+1))
-                    assertTrue(a<m.nIns() && m.in(a)!=null);
-            assertFalse(n instanceof PhiNode && n.isMem() &&
-                !(n instanceof MemPhiNode) && !(n instanceof BulkMemPhiNode));
-            return null;
-        });
-        assertTrue(phis[0]>=3);
-        assertArrayEquals(new Object[]{1L,2L,3L},((Evaluator.Obj)Evaluator.evaluate(stop,4)).fields());
-    }
-
-    @Test public void testLateSliceWorklist() throws ReflectiveOperationException {
-        // Seed 97 exposed a store selecting a bulk predecessor without queuing
-        // it. Keep both the worklist assertion and the final heap check.
-        for (int seed : new int[]{0,97,123,456}) {
-            var parser = new Parser(Chapter10Test.NESTED_MEMORY);
-            var field = IterPeeps.class.getDeclaredField("WORK");
-            field.setAccessible(true);
-            Object work = field.get(null);
-            field = work.getClass().getDeclaredField("_R");
-            field.setAccessible(true);
-            ((java.util.Random)field.get(work)).setSeed(seed);
-            var stop = parser.parse().iterate();
-            assertArrayEquals(new Object[]{9L,25L,17L},((Evaluator.Obj)Evaluator.evaluate(stop,4)).fields());
-        }
-    }
-}
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/Chapter11Test.java b/chapter11/src/test/java/com/seaofnodes/simple/Chapter11Test.java
index 4c2b42f1..5f92c9c1 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/Chapter11Test.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/Chapter11Test.java
@@ -1,567 +1,64 @@
 package com.seaofnodes.simple;
 
-
+import com.seaofnodes.simple.node.*;
 import com.seaofnodes.simple.evaluator.Evaluator;
-import com.seaofnodes.simple.node.StopNode;
 import org.junit.Test;
-
-
-import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.*;
 
 public class Chapter11Test {
-
-    // A placeholder test used to rapidly rotate through fuzzer produced issues
-    @Test
-    public void testFuzzer() {
-        Parser parser = new Parser(
-"""
-while(-----arg) {
-    while(-arg) {
-        while(-----arg*---0) {
-                int N=--false==false<--arg;
-                while(N<-4==N) {
-                    N=N+N;
-                }
-            }
-        {
-            int kzEl_r7EYz=3*----0!=-arg<(37*--97!=0/arg==arg)<=-(--arg!=0);
-            while(kzEl_r7EYz<---1) {
-                kzEl_r7EYz=kzEl_r7EYz+kzEl_r7EYz*arg>=24;
-                if(7) continue;
-                kzEl_r7EYz=false;
-                if(-kzEl_r7EYz+arg<-3) continue;
-                else {
-                    while(kzEl_r7EYz) continue;
-                    arg=----3;
-                    kzEl_r7EYz=-(-----arg*1>-kzEl_r7EYz);
-                    int v2uF_4ba=9;
-                }
-            }
-        }
-        int pjcp7rv=arg;
-        {
-            int m2ya3=--arg-pjcp7rv;
-            while(m2ya3<-----pjcp7rv>=pjcp7rv+--pjcp7rv!=---pjcp7rv!=-arg<---(-m2ya3)>m2ya3<=-----true>14!=--m2ya3) {
-                m2ya3=m2ya3+-(--0<=false<pjcp7rv/arg<=-true);
-                while((--m2ya3)<--arg<-----arg*false!=arg<pjcp7rv*arg) {
-                    pjcp7rv=-3+-arg;
-                    break;
-                }
-                while(-3) {
-                    while(67+0-61) m2ya3=m2ya3;
-                    if(----pjcp7rv==---(---arg)) pjcp7rv=0!=-23;
-                    else pjcp7rv=----89;
-                    while(m2ya3!=m2ya3<pjcp7rv) m2ya3=1;
-                    while(--arg<=pjcp7rv) pjcp7rv=-32<=-m2ya3+62;
-                }
-                break;
-            }
-        }
-        {
-            int arg=-1<-9!=(-arg>=-pjcp7rv>=arg<=arg);
-            while(arg<-arg) {
-                arg=arg+--arg;
-                {
-                    while((--93)--pjcp7rv*-pjcp7rv+arg) arg=0-(6>=(--(---41/(0))!=--pjcp7rv)>=---2*33);
-                    pjcp7rv=11;
-                    int c=pjcp7rv;
-                    if(--107) break;
-                    else break;
-                }
-            }
-        }
-        pjcp7rv=pjcp7rv;
-        int aR0Wkua=-pjcp7rv==pjcp7rv;
-        {
-            if(-0!=-0) while(-true) break;
-            else {
-                while(aR0Wkua) pjcp7rv=-0/pjcp7rv;
-                pjcp7rv=pjcp7rv;
-            }
-        }
-    }
-    if(-arg) {
-        {
-            int Isdlt0fr91=0!=arg;
-            while(Isdlt0fr91<-Isdlt0fr91==-Isdlt0fr91+true) {
-                Isdlt0fr91=Isdlt0fr91+-1!=true;
-                if(-arg) if(--arg<=Isdlt0fr91) Isdlt0fr91=-Isdlt0fr91;
-                int i=---arg<---arg!=--40;
-                {
-                    int jVX43Ln4Dm=-(6)==-Isdlt0fr91/----0;
-                    while(jVX43Ln4Dm<--(3-3)) {
-                        jVX43Ln4Dm=jVX43Ln4Dm+-0<25;
-                        i=24<--(jVX43Ln4Dm);
-                    }
-                }
-                i=(arg!=----false>=7);
-                int Te=5>-arg;
-                break;
-            }
-        }
-        arg=arg!=--true/arg;
-        {
-            int UX=arg;
-            while(UX<-3*arg) {
-                UX=UX+arg/-1;
-                arg=-3--(-UX--47<arg==--arg==arg)/arg--UX>=-arg;
-                if(---12) while(-UX) break;
-                break;
-            }
-        }
-        continue;
-    }
-    if(arg) arg=--0;
-    else if(1) continue;
-    int DtTlhjYq=19==arg;
-    {
-        arg=--DtTlhjYq<=(DtTlhjYq/---DtTlhjYq<=-DtTlhjYq);
-        if(---arg) continue;
-        else {
-                int Zsl=40;
-                while(Zsl<--Zsl--false>((Zsl))==Zsl!=--DtTlhjYq-DtTlhjYq-DtTlhjYq) {
-                    Zsl=Zsl+arg;
-                }
-            }
-        if((arg)) if(-DtTlhjYq) {
-            }
-            else while(((2)==3*arg/DtTlhjYq)<=0==---arg) return false;
-        else {
-                int lwbF=arg>=0;
-                while(lwbF<57) {
-                    lwbF=lwbF+--(-arg+lwbF)>=-2>=arg!=arg;
-                    arg=----0+0;
-                    while(49) break;
-                    if(true) DtTlhjYq=-----arg;
-                    DtTlhjYq=0!=-----(0);
-                }
-            }
-        arg=---arg!=DtTlhjYq/--0;
-        DtTlhjYq=-DtTlhjYq/(--arg<arg);
-        if(32) {
-                int q=-DtTlhjYq;
-                while(q<arg*(0*q)/0) {
-                    q=q+DtTlhjYq;
-                    DtTlhjYq=arg;
-                }
-            }
-        else if(--arg) if(15) break;
-                else arg=0==arg<=-55>DtTlhjYq;
-            else {
-            }
-        DtTlhjYq=-0;
-        {
-            while((0)<-arg) DtTlhjYq=-DtTlhjYq;
-        }
-        if(30/--(arg)>=0) DtTlhjYq=-0>=arg;
-        else {
-            int Y2wcIQJ=--DtTlhjYq*---11;
-            if(arg==arg) {
-                Y2wcIQJ=-----Y2wcIQJ;
-                Y2wcIQJ=Y2wcIQJ<7;
-                if(DtTlhjYq) arg=arg;
-                else break;
-                while(-arg!=-31==(false<=-15>=-DtTlhjYq+--6*-----Y2wcIQJ<=---arg!=-Y2wcIQJ<=---0<-arg*--Y2wcIQJ)) DtTlhjYq=arg!=3;
-            }
-            continue;
-        }
-        arg=DtTlhjYq;
-        arg=--3/(---arg)>=80>=-DtTlhjYq<=DtTlhjYq;
-        arg=51+---(-true)!=arg!=----1==-DtTlhjYq;
-        if(11<=arg) if((arg)+79<32+(-arg)) continue;
-            else if(true==DtTlhjYq) break;
-        break;
-    }
-}
-if(arg!=62==arg) {
-    while(---arg) {
-        {
-            int bhmDacPM=arg/arg;
-            while(bhmDacPM<arg) {
-                bhmDacPM=bhmDacPM+80*((-bhmDacPM)/---bhmDacPM>1)<bhmDacPM-2!=7;
-                arg=-0;
-                arg=bhmDacPM>=-arg+-arg;
-                break;
-            }
-        }
-        int arg=true;
-        arg=arg<=arg;
-        {
-            int KlC=30;
-            while(KlC<-2) {
-                KlC=KlC+-1!=25<=-KlC>KlC>----0;
-                int Ij=arg>=-arg<=---10;
-                {
-                    int LAbgurVa2R=-arg!=Ij;
-                    while(LAbgurVa2R<-true) {
-                        LAbgurVa2R=LAbgurVa2R+Ij;
-                        KlC=-LAbgurVa2R;
-                        Ij=42*(-Ij>true);
-                        while(Ij) arg=KlC;
-                        KlC=-----7>-(--KlC<--7)==-LAbgurVa2R;
-                    }
-                }
-                int a=Ij<=-KlC;
-                if(Ij) {
-                    int r1W=a!=-false;
-                }
-                else {
-                    arg=56>=Ij;
-                    while(54) break;
-                    arg=8>=-(a<--Ij)/a>=-a-KlC;
-                }
-                int Yt_T=KlC;
-                arg=KlC;
-            }
-        }
-        if(----false/--arg/12+-----0) if(-9+-arg) while(arg!=(arg)) arg=--1>=-71-arg!=---(--arg*11+102)/--arg;
-            else if(----arg) continue;
-        if(-arg-arg) {
-            arg=-(-arg)*--(-3)<(-7==-arg----arg);
-            {
-                int arg=arg;
-                while(arg<-0>arg==-arg-(-arg>1+11)) {
-                    arg=arg+6-arg!=--0>---30>=---arg<=arg/(3)+---arg;
-                }
-            }
-            arg=-arg+arg;
-            arg=--47+-arg<1>arg*(-arg==-arg--0>3);
-            arg=(----arg)!=arg+--59;
-            arg=--4+arg==-(arg)-arg;
-        }
-        else {
-            while(--true-----true*-25+-18>arg>=-----(-arg)---13) {
-                arg=-0+--true<false;
-                continue;
-            }
-            arg=true<=arg;
-            break;
-        }
-        arg=arg*22<--(0+-arg);
-        {
-            continue;
-        }
-    }
-    arg=1*---((3<=true)==---2);
-    arg=7+-(-1);
-    return arg+--true;
-}
-else {
-    int o3ypEsewxM=-(---arg);
-    int vzXB=(-(---11<=--o3ypEsewxM>=--0))<=-0/-arg;
-    int L=-arg;
-    int B4mHcrf=---vzXB;
-    int oZWGdzZl=-o3ypEsewxM;
-    int K6tQqa1=11;
-    while(0!=--L) {
-            int sdZfTM=vzXB*true+K6tQqa1;
-            while(sdZfTM<false) {
-                sdZfTM=sdZfTM+arg;
-                sdZfTM=oZWGdzZl;
-                K6tQqa1=-K6tQqa1;
-                arg=---K6tQqa1;
-                while((3+-K6tQqa1)<oZWGdzZl) {
-                    if(-----(-1)) sdZfTM=-false;
-                    {}
-                }
-                K6tQqa1=vzXB!=-(B4mHcrf+-7>false);
-                sdZfTM=vzXB;
-            }
-        }
-    L=false;
-    while(31) B4mHcrf=arg;
-    oZWGdzZl=-0<--oZWGdzZl<=--2;
-    if(K6tQqa1>=20<=46) {
-        if(-1+-L) if(oZWGdzZl) {
-                int wmhv=-----0;
-            }
-        int arg=0;
-        o3ypEsewxM=---(oZWGdzZl);
-        return -oZWGdzZl/0;
-    }
-    else if(arg) {
-            int yKk5=B4mHcrf>=4>K6tQqa1<-B4mHcrf/o3ypEsewxM;
-            return -K6tQqa1;
-        }
-        else {
-            if(---0) {
-                {}
-                {}
-            }
-            return o3ypEsewxM;
+    @Test public void testIndependentField() {
+        var stop = new Parser("""
+            struct S { int x; int y; }
+            S s = new S;
+            s.x = 42;
+            while (arg > 0) { s.y = s.y + arg; arg = arg - 1; }
+            return s.x;
+            """).parse().iterate();
+        assertEquals("return 42;",stop.toString());
+        assertEquals(42L,Evaluator.evaluate(stop,5));
+        assertNull(stop.walk(n -> n instanceof LoadNode ? n : null));
+    }
+
+    @Test public void testParallelMemoryPhis() {
+        var stop = new Parser("""
+            struct S { int x; int y; int z; }
+            S a = new S; S b = new S;
+            S p = a; if (arg) p = b;
+            while (arg > 0) {
+                a.x = p.x + arg;
+                a.y = p.y + 2;
+                a.z = p.z + 3;
+                arg = arg - 1;
+            }
+            return a;
+            """).parse().iterate();
+        int[] phis = {0};
+        stop.walk(n -> {
+            if (n instanceof MemPhiNode) phis[0]++;
+            if (n instanceof MemMergeNode m && m.in(1) instanceof BulkMemPhiNode b)
+                for(int a=b._aliases.nextSetBit(0); a>=0; a=b._aliases.nextSetBit(a+1))
+                    assertTrue(a<m.nIns() && m.in(a)!=null);
+            assertFalse(n instanceof PhiNode && n.isMem() &&
+                !(n instanceof MemPhiNode) && !(n instanceof BulkMemPhiNode));
+            return null;
+        });
+        assertTrue(phis[0]>=3);
+        assertArrayEquals(new Object[]{1L,2L,3L},((Evaluator.Obj)Evaluator.evaluate(stop,4)).fields());
+    }
+
+    @Test public void testLateSliceWorklist() throws ReflectiveOperationException {
+        // Seed 97 exposed a store selecting a bulk predecessor without queuing
+        // it. Keep both the worklist assertion and the final heap check.
+        for (int seed : new int[]{0,97,123,456}) {
+            var parser = new Parser(Chapter10Test.NESTED_MEMORY);
+            var field = IterPeeps.class.getDeclaredField("WORK");
+            field.setAccessible(true);
+            Object work = field.get(null);
+            field = work.getClass().getDeclaredField("_R");
+            field.setAccessible(true);
+            ((java.util.Random)field.get(work)).setSeed(seed);
+            var stop = parser.parse().iterate();
+            assertArrayEquals(new Object[]{9L,25L,17L},((Evaluator.Obj)Evaluator.evaluate(stop,4)).fields());
         }
-}
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("Stop[ return 9; return 0; return 0; ]", stop.toString());
-    }
-
-
-
-    @Test
-    public void testPrimes() {
-        Parser parser = new Parser(
-"""
-if( arg < 2 ) return 0;
-int primeCount = 1;
-int prime = 3;
-while( prime <= arg ) {
-    int isPrime = 1;
-    // Check for even case, so the next loop need only check odds
-    if( (prime/2)*2 == prime )
-        continue;
-    // Check odds up to sqrt of prime
-    int j = 3;
-    while( j*j <= prime ) {
-        if( (prime/j)*j == prime ) {
-            isPrime = 0;
-            break;
-        }
-        j = j + 2;
-    }
-    if( isPrime )
-        primeCount = primeCount + 1;
-    prime = prime + 2;
-}
-return primeCount;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("Stop[ return 0; return Phi(Loop20,1,Phi(Region82,Phi_primeCount,Phi(Region77,(Phi_primeCount+1),Phi_primeCount))); ]", stop.toString());
-        assertEquals(0L, Evaluator.evaluate(stop,  1)); // No primes 1 or below
-        assertEquals(1L, Evaluator.evaluate(stop,  2)); // 2
-        assertEquals(2L, Evaluator.evaluate(stop,  3)); // 2, 3
-        assertEquals(2L, Evaluator.evaluate(stop,  4)); // 2, 3
-        assertEquals(3L, Evaluator.evaluate(stop,  5)); // 2, 3, 5
-        assertEquals(4L, Evaluator.evaluate(stop, 10)); // 2, 3, 5, 7
-    }
-
-    @Test
-    public void testAntiDeps1() {
-        Parser parser = new Parser(
-"""
-struct S { int f; }
-S v=new S;
-v.f = 2;
-int i=new S.f;
-i=v.f;
-if (arg) v.f=1;
-return i;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return .f;", stop.toString());
-    }
-
-    @Test
-    public void testAntiDeps2() {
-        Parser parser = new Parser(
-"""
-struct S { int f; }
-S v = new S;
-S t = new S;
-int i = 0;
-if (arg) {
-    if (arg+1) v = t;
-    i = v.f;
-} else {
-    v.f = 2;
-}
-return i;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region34,.f,0);", stop.toString());
-    }
-
-    @Test
-    public void testAntiDeps3() {
-        Parser parser = new Parser(
-"""
-struct S { int f; }
-S v0 = new S;
-S? v1;
-if (arg) v1 = new S;
-if (v1) {
-    v0.f = v1.f;
-} else {
-    v0.f = 2;
-}
-return v0;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return new S;", stop.toString());
-    }
-
-
-    @Test
-    public void testAntiDeps4() {
-        Parser parser = new Parser(
-"""
-struct S { int f; }
-S v = new S;
-S t = new S;
-int i = v.f;
-if (arg+1) arg= 0;
-while (arg) v.f = 2;
-return i;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return .f;", stop.toString());
-    }
-
-    @Test
-    public void testAntiDeps5() {
-        Parser parser = new Parser(
-"""
-struct S { int f; }
-S v = new S;
-while(1) {
-    while(arg+1) { arg=arg-1; }
-    if (arg) break;
-    v.f = 2;
-}
-return v;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return new S;", stop.toString());
-    }
-
-    @Test
-    public void testAntiDeps6() {
-        Parser parser = new Parser(
-"""
-struct s { int v; }
-s ptr=new s;
-while( -arg )
-  ptr = new s;
-while(1)
-  arg = arg+ptr.v;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
-    }
-
-    @Test
-    public void testAntiDeps7() {
-        Parser parser = new Parser(
-"""
-struct S { int f; }
-S v = new S;
-S t = new S;
-int i = v.f;
-while (arg) {
-    v.f = arg;
-    arg = arg-1;
-}
-return i;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return .f;", stop.toString());
-    }
-
-    @Test
-    public void testAntiDeps8() {
-        Parser parser = new Parser(
-"""
-struct S { int f; }
-S v = new S;
-S t = new S;
-while(arg) {
-    arg=arg-1;
-    int f = v.f;
-    v.f = 2;
-    if (arg) arg = f;
-    else v.f = 3;
-}
-return arg;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Loop15,arg,Phi(Region39,.f,0));", stop.toString());
-    }
-
-    @Test
-    public void testAntiDeps9() {
-        Parser parser = new Parser(
-"""
-struct S { int f; }
-S v = new S;
-S t = new S;
-if (arg) {
-    v.f=2;
-    int i=t.f;
-    v.f=i;
-}
-return v;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return new S;", stop.toString());
-    }
-
-    @Test
-    public void testExample2() {
-        Parser parser = new Parser(
-                                   """
-struct S { int f; }
-S v = new S;
-int i = arg;
-while (arg > 0) {
-    int j = i/3;
-    if (arg == 5)
-        v.f = j;
-    arg = arg - 1;
-}
-return v;
-""");
-        StopNode stop = parser.parse().iterate();
-        //assertEquals("return new S;", stop.toString());
-    }
-
-    @Test
-    public void testSplit() {
-        Parser parser = new Parser(
-                                   """
-struct S { int f; }
-S s = new S;
-if( arg==0 ) s.f = 1;
-else if (arg == 1) s.f = 1;
-return s.f;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return Phi(Region41,1,Phi(Region36,1,0));", stop.toString());
-        assertEquals(1L, Evaluator.evaluate(stop,  0));
-        assertEquals(1L, Evaluator.evaluate(stop,  1));
-        assertEquals(0L, Evaluator.evaluate(stop,  2));
-    }
-
-    @Test
-    public void testScheduleUse() {
-        Parser parser = new Parser(
-"""
-int v0=0;
-while(0>=0) {
-    int v1=0;
-    v1=v0;
-    if(v1*0)
-        v0=-v1;
-}
-return 0;
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
-    }
-
-    @Test
-    public void testLoopCarriedDep() {
-        Parser parser = new Parser(
-"""
-int v0=0;
-{
-    int v1=0;
-    while(v1) {
-        v1=1+(v0!=0);
-        v0=v1/0;
-    }
-}
-""");
-        StopNode stop = parser.parse().iterate();
-        assertEquals("return 0;", stop.toString());
     }
 }
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/FuzzerWrap.java b/chapter11/src/test/java/com/seaofnodes/simple/FuzzerWrap.java
index 52c2a014..019140ad 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/FuzzerWrap.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/FuzzerWrap.java
@@ -29,8 +29,8 @@ public class FuzzerWrap {
             fuzzer.fuzzPeepsRegression(seed);
     }
 
-    @Ignore
     @Test
+    @Ignore
     public void fuzzPeepsLarge() {
         var fuzzer = new Fuzzer();
         for (int i=0; i<1000000; i++)
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java b/chapter11/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java
index 355d906b..ac7c5e09 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java
@@ -140,8 +140,7 @@ public class Evaluator {
             case StoreNode    store -> store(store);
             case MemMergeNode merge -> MEMORY;
             case NewNode      alloc -> alloc(alloc);
-            case CProjNode    cproj -> ((Object[])val(cproj.ctrl()))[cproj._idx];
-            case ProjNode     proj  -> ((Object[])val( proj.in(0) ))[ proj._idx];
+            case ProjNode     proj  -> ((Object[])val(proj.ctrl()))[proj._idx];
             default                 -> throw new AssertionError("Unexpected node " + node);
         };
     }
diff --git a/chapter11/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java b/chapter11/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java
index d16f4300..48ac0562 100644
--- a/chapter11/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java
+++ b/chapter11/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java
@@ -164,7 +164,7 @@ public class Scheduler {
      * @return true if the node is not XCtrl.
      */
     private static boolean isNotXCtrl(Node node) {
-        return !(node instanceof ConstantNode c && c.compute() == Type.XCONTROL) && !(node instanceof XCtrlNode);
+        return !(node instanceof ConstantNode c && c.compute() == Type.XCONTROL);
     }
 
     /**
@@ -215,7 +215,7 @@ public class Scheduler {
     private void refinePlacement(NodeData data, BasicBlock block) {
         assert !isPinnedNode(data);
         data.block = data.block == null ? block : dom(data.block, block);
-        assert isValid(data);
+        assert isValid(data) : data.node.uniqueName()+" at "+data.block.entry.uniqueName();
     }
 
     /**
@@ -328,8 +328,6 @@ public class Scheduler {
             for(int i=1; i<r.nIns(); i++) {
                 if (od(r.in(i)).map(d->d.block==null).orElse(false)) return false;
             }
-        } else if (node instanceof XCtrlNode) {
-            return false;
         } else {
             assert d(node.in(0)).block != null;
         }
@@ -405,7 +403,7 @@ public class Scheduler {
                 }
             }
             if (!(node instanceof ReturnNode))
-                for (Node n:node._outputs) if (n!=null && n.isCFG() && isCFGNodeReady(n) && d(n).block == null) queue.push(d(n));
+                for (Node n:node._outputs) if (n.isCFG() && isCFGNodeReady(n) && d(n).block == null) queue.push(d(n));
             var b = block;
             for(var in:data.node._inputs) od(in).ifPresent(d->update(d, b));
         }
@@ -451,7 +449,7 @@ public class Scheduler {
             node = data.node;
             assert node.isCFG();
             if (!(node instanceof ReturnNode)) {
-                for (var out : node._outputs) if (out!=null && out.isCFG() && isNotXCtrl(out)) markAlive(cfgQueue, out, true);
+                for (var out : node._outputs) if (out.isCFG() && isNotXCtrl(out)) markAlive(cfgQueue, out, true);
             }
             for (var in : node._inputs) if(in!=null && !in.isCFG() && isNotXCtrl(in)) markAlive(dataQueue, in, false);
         }
@@ -505,7 +503,7 @@ public class Scheduler {
      */
     private static Node findSingleCFGOut(Node node) {
         if (node instanceof StartNode) {
-            for(var n:node._outputs) if (n instanceof CProjNode p && p._idx==0) return p;
+            for(var n:node._outputs) if (n instanceof ProjNode p && p._idx==0) return p;
             return null;
         }
         assert node._outputs.stream().filter(Node::isCFG).limit(2).count()<=1;
@@ -572,7 +570,7 @@ public class Scheduler {
             switch(block.exit) {
                 case null: break;
                 case IfNode i:
-                    for(var out:i._outputs) if (out instanceof CProjNode p) block.next[p._idx] = blocks.get(p);
+                    for(var out:i._outputs) if (out instanceof ProjNode p) block.next[p._idx] = blocks.get(p);
                     break;
                 case RegionNode r:
                     block.next[0] = blocks.get(r);