# HG changeset patch
# User Thomas Wuerthinger <thomas@wuerthinger.net>
# Date 1306519076 -7200
# Node ID c3f64b66fc78b81fb2bb1a42f98416f51a8336cf
# Parent  095162a84dcce761f6b581ff58418f27a1c35636
Towards removing the next pointer from Constant and ArithmeticOp

diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/oracle/max/graal/schedule/Block.java
--- a/graal/GraalCompiler/src/com/oracle/max/graal/schedule/Block.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/oracle/max/graal/schedule/Block.java	Fri May 27 19:57:56 2011 +0200
@@ -38,6 +38,25 @@
     private Block dominator;
     private final List<Block> dominators = new ArrayList<Block>();
 
+    private Node firstNode;
+    private Node lastNode;
+
+    public Node firstNode() {
+        return firstNode;
+    }
+
+    public void setFirstNode(Node node) {
+        this.firstNode = node;
+    }
+
+    public Node lastNode() {
+        return lastNode;
+    }
+
+    public void setLastNode(Node node) {
+        this.lastNode = node;
+    }
+
     public List<Block> getSuccessors() {
         return Collections.unmodifiableList(successors);
     }
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/oracle/max/graal/schedule/Schedule.java
--- a/graal/GraalCompiler/src/com/oracle/max/graal/schedule/Schedule.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/oracle/max/graal/schedule/Schedule.java	Fri May 27 19:57:56 2011 +0200
@@ -68,7 +68,16 @@
     private Block assignBlock(Node n, Block b) {
         assert nodeToBlock.get(n) == null;
         nodeToBlock.set(n, b);
-        b.getInstructions().add(n);
+        if (b.firstNode() == null) {
+            b.setFirstNode(n);
+            b.setLastNode(n);
+        } else {
+            if (b.lastNode() != null) {
+                b.getInstructions().add(b.lastNode());
+            }
+            b.setLastNode(n);
+        }
+        b.setLastNode(n);
         return b;
     }
 
@@ -164,9 +173,23 @@
             }
         }
 
+        for (Node n : graph.getNodes()) {
+            if (n instanceof FrameState) {
+                FrameState f = (FrameState) n;
+                if (f.predecessors().size() == 1) {
+                    Block predBlock = nodeToBlock.get(f.predecessors().get(0));
+                    assert predBlock != null;
+                    nodeToBlock.set(f, predBlock);
+                    predBlock.getInstructions().add(f);
+                } else {
+                    assert f.predecessors().size() == 0;
+                }
+            }
+        }
+
         computeDominators();
-        assignLatestPossibleBlockToNodes();
-        sortNodesWithinBlocks();
+
+
 
         // Add successors of loop end nodes. Makes the graph cyclic.
         for (Node n : blockBeginNodes) {
@@ -177,6 +200,9 @@
             }
         }
 
+        assignLatestPossibleBlockToNodes();
+        sortNodesWithinBlocks();
+
         //print();
     }
 
@@ -195,16 +221,34 @@
         if (prevBlock != null) {
             return prevBlock;
         }
+        TTY.println("handling " + n);
 
         Block block = null;
         for (Node succ : n.successors()) {
             block = getCommonDominator(block, assignLatestPossibleBlockToNode(succ));
         }
         for (Node usage : n.usages()) {
-            block = getCommonDominator(block, assignLatestPossibleBlockToNode(usage));
+            TTY.println("usaged at: " + usage.id() + ", " + nodeToBlock.get(usage));
+            if (usage instanceof Phi) {
+                Phi phi = (Phi) usage;
+                Merge merge = phi.block();
+                Block mergeBlock = nodeToBlock.get(merge);
+                assert mergeBlock != null;
+                for (int i = 0; i < phi.valueCount(); ++i) {
+                    if (phi.valueAt(i) == n) {
+                        block = getCommonDominator(block, mergeBlock.getPredecessors().get(i));
+                    }
+                }
+            } else {
+                block = getCommonDominator(block, assignLatestPossibleBlockToNode(usage));
+            }
         }
 
+        TTY.println("assigning block " + block + " to node " + n);
         nodeToBlock.set(n, block);
+        if (block != null) {
+            block.getInstructions().add(n);
+        }
         return block;
     }
 
@@ -227,22 +271,24 @@
 
     private void sortNodesWithinBlocks(Block b, NodeBitMap map) {
         List<Node> instructions = b.getInstructions();
-
-        Collections.shuffle(instructions);
-
         List<Node> sortedInstructions = new ArrayList<Node>();
+        assert !map.isMarked(b.firstNode()) && nodeToBlock.get(b.firstNode()) == b;
+        addToSorting(b, b.firstNode(), sortedInstructions, map);
         for (Node i : instructions) {
             addToSorting(b, i, sortedInstructions, map);
         }
+        addToSorting(b, b.lastNode(), sortedInstructions, map);
+        //assert b.firstNode() == sortedInstructions.get(0) : b.firstNode();
+    //    assert b.lastNode() == sortedInstructions.get(sortedInstructions.size() - 1);
         b.setInstructions(sortedInstructions);
-//        TTY.println("Block " + b);
-//        for (Node n : sortedInstructions) {
-//            TTY.println("Node: " + n);
-//        }
+        TTY.println("Block " + b);
+        for (Node n : sortedInstructions) {
+            TTY.println("Node: " + n);
+        }
     }
 
     private void addToSorting(Block b, Node i, List<Node> sortedInstructions, NodeBitMap map) {
-        if (i == null || map.isMarked(i) || nodeToBlock.get(i) != b || i instanceof Phi || i instanceof FrameState || i instanceof Local) {
+        if (i == null || map.isMarked(i) || nodeToBlock.get(i) != b || i instanceof Phi || i instanceof Local) {
             return;
         }
 
@@ -254,9 +300,18 @@
             addToSorting(b, pred, sortedInstructions, map);
         }
 
+        map.mark(i);
+
+        for (Node succ : i.successors()) {
+            if (succ instanceof FrameState) {
+                addToSorting(b, succ, sortedInstructions, map);
+            }
+        }
+
         // Now predecessors and inputs are scheduled => we can add this node.
-        sortedInstructions.add(i);
-        map.mark(i);
+        if (!(i instanceof FrameState)) {
+            sortedInstructions.add(i);
+        }
     }
 
     private void computeDominators() {
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/alloc/EdgeMoveOptimizer.java
--- a/graal/GraalCompiler/src/com/sun/c1x/alloc/EdgeMoveOptimizer.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/alloc/EdgeMoveOptimizer.java	Fri May 27 19:57:56 2011 +0200
@@ -190,7 +190,7 @@
         List<LIRInstruction> instructions = block.lir().instructionsList();
 
         assert numSux == 2 : "method should not be called otherwise";
-        assert instructions.get(instructions.size() - 1).code == LIROpcode.Branch : "block with successor must end with branch";
+        assert instructions.get(instructions.size() - 1).code == LIROpcode.Branch : "block with successor must end with branch block=B" + block.blockID();
         assert instructions.get(instructions.size() - 1) instanceof LIRBranch : "branch must be LIROpBranch";
         assert ((LIRBranch) instructions.get(instructions.size() - 1)).cond() == Condition.TRUE : "block must end with unconditional branch";
 
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/gen/LIRGenerator.java
--- a/graal/GraalCompiler/src/com/sun/c1x/gen/LIRGenerator.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/gen/LIRGenerator.java	Fri May 27 19:57:56 2011 +0200
@@ -1466,12 +1466,12 @@
         }
     }
 
-    protected LIRDebugInfo stateFor(Instruction x) {
+    protected LIRDebugInfo stateFor(Value x) {
         assert lastState != null : "must have state before instruction for " + x;
         return stateFor(x, lastState);
     }
 
-    protected LIRDebugInfo stateFor(Instruction x, FrameState state) {
+    protected LIRDebugInfo stateFor(Value x, FrameState state) {
         if (compilation.placeholderState != null) {
             state = compilation.placeholderState;
         }
@@ -1540,7 +1540,7 @@
             }
         }
         // the value must be a constant or have a valid operand
-        assert operand.isLegal() : "this root has not been visited yet";
+        assert operand.isLegal() : "this root has not been visited yet; instruction=" + instruction;
         return operand;
     }
 
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/graph/CriticalEdgeFinder.java
--- a/graal/GraalCompiler/src/com/sun/c1x/graph/CriticalEdgeFinder.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/graph/CriticalEdgeFinder.java	Fri May 27 19:57:56 2011 +0200
@@ -105,8 +105,8 @@
 
         // This goto is not a safepoint.
         Anchor e = new Anchor(null, graph);
-        Node sourceInstruction = source.getInstructions().get(source.getInstructions().size() - 1);
-        Node targetInstruction = target.getInstructions().get(0);
+        Node sourceInstruction = source.lastInstruction();
+        Node targetInstruction = target.firstInstruction();
         int sourceInstructionPredIndex = targetInstruction.predecessors().indexOf(sourceInstruction);
         assert sourceInstructionPredIndex != -1 : "must find source instruction " + sourceInstruction + " in predecessor array of target instruction " + targetInstruction;
         int replacedIndex = targetInstruction.predecessorsIndex().get(sourceInstructionPredIndex);
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/graph/GraphBuilder.java
--- a/graal/GraalCompiler/src/com/sun/c1x/graph/GraphBuilder.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/graph/GraphBuilder.java	Fri May 27 19:57:56 2011 +0200
@@ -1031,13 +1031,17 @@
     }
 
     private Value appendConstant(CiConstant constant) {
-        return appendWithBCI(new Constant(constant, graph));
+        return append(new Constant(constant, graph));
     }
 
     private Value append(Instruction x) {
         return appendWithBCI(x);
     }
 
+    private Value append(Value v) {
+        return v;
+    }
+
     private Value appendWithBCI(Instruction x) {
         if (x.isAppended()) {
             // the instruction has already been added
@@ -1093,7 +1097,7 @@
     private Value synchronizedObject(FrameStateAccess state, RiMethod target) {
         if (isStatic(target.accessFlags())) {
             Constant classConstant = new Constant(target.holder().getEncoding(Representation.JavaClass), graph);
-            return appendWithBCI(classConstant);
+            return append(classConstant);
         } else {
             return state.localAt(0);
         }
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/graph/IR.java
--- a/graal/GraalCompiler/src/com/sun/c1x/graph/IR.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/graph/IR.java	Fri May 27 19:57:56 2011 +0200
@@ -90,6 +90,9 @@
             map.put(b, block);
             block.setInstructions(b.getInstructions());
             block.setLinearScanNumber(b.blockID());
+
+            block.setFirstInstruction(b.firstNode());
+            block.setLastInstruction(b.lastNode());
             lirBlocks.add(block);
         }
 
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/ArrayLength.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/ArrayLength.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/ArrayLength.java	Fri May 27 19:57:56 2011 +0200
@@ -56,7 +56,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         if (i instanceof ArrayLength) {
             ArrayLength o = (ArrayLength) i;
             return array() == o.array();
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/CheckCast.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/CheckCast.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/CheckCast.java	Fri May 27 19:57:56 2011 +0200
@@ -78,7 +78,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         if (i instanceof CheckCast) {
             CheckCast o = (CheckCast) i;
             return targetClass == o.targetClass && object() == o.object();
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/Constant.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/Constant.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/Constant.java	Fri May 27 19:57:56 2011 +0200
@@ -33,7 +33,7 @@
  * The {@code Constant} instruction represents a constant such as an integer value,
  * long, float, object reference, address, etc.
  */
-public final class Constant extends Instruction {
+public final class Constant extends Value {
 
     private static final int INPUT_COUNT = 0;
     private static final int SUCCESSOR_COUNT = 0;
@@ -164,7 +164,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         return i instanceof Constant && ((Constant) i).value.equivalent(this.value);
     }
 
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/Convert.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/Convert.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/Convert.java	Fri May 27 19:57:56 2011 +0200
@@ -88,7 +88,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         if (i instanceof Convert) {
             Convert o = (Convert) i;
             return opcode == o.opcode && value() == o.value();
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/IfOp.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/IfOp.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/IfOp.java	Fri May 27 19:57:56 2011 +0200
@@ -119,7 +119,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         if (i instanceof IfOp) {
             IfOp o = (IfOp) i;
             return opcode == o.opcode && x() == o.x() && y() == o.y() && trueValue() == o.trueValue() && falseValue() == o.falseValue();
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/InstanceOf.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/InstanceOf.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/InstanceOf.java	Fri May 27 19:57:56 2011 +0200
@@ -59,7 +59,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         if (i instanceof InstanceOf) {
             InstanceOf o = (InstanceOf) i;
             return targetClass == o.targetClass && object() == o.object();
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/Instruction.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/Instruction.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/Instruction.java	Fri May 27 19:57:56 2011 +0200
@@ -145,38 +145,6 @@
         return (Instruction) predecessors().get(j);
     }
 
-    @Override
-    public Merge block() {
-        Instruction cur = this;
-        while (!(cur instanceof Merge)) {
-            List<Node> preds = cur.predecessors();
-            cur = (Instruction) preds.get(0);
-        }
-        return (Merge) cur;
-    }
-
-    /**
-     * Compute the value number of this Instruction. Local and global value numbering
-     * optimizations use a hash map, and the value number provides a hash code.
-     * If the instruction cannot be value numbered, then this method should return
-     * {@code 0}.
-     * @return the hashcode of this instruction
-     */
-    public int valueNumber() {
-        return 0;
-    }
-
-    /**
-     * Checks that this instruction is equal to another instruction for the purposes
-     * of value numbering.
-     * @param i the other instruction
-     * @return {@code true} if this instruction is equivalent to the specified
-     * instruction w.r.t. value numbering
-     */
-    public boolean valueEqual(Instruction i) {
-        return false;
-    }
-
     /**
      * Gets the state after the instruction, if it is recorded. Typically only
      * instances of {@link BlockEnd} have a non-null state after.
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/Local.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/Local.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/Local.java	Fri May 27 19:57:56 2011 +0200
@@ -46,11 +46,6 @@
         this.inputs().set(0, graph.start());
     }
 
-    @Override
-    public Merge block() {
-        return null;
-    }
-
     /**
      * Gets the index of this local.
      * @return the index
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/Merge.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/Merge.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/Merge.java	Fri May 27 19:57:56 2011 +0200
@@ -126,12 +126,12 @@
         //}
 
         // print predecessors
-        if (!blockPredecessors().isEmpty()) {
-            out.print(" pred:");
-            for (Instruction pred : blockPredecessors()) {
-                out.print(pred.block());
-            }
-        }
+//        if (!blockPredecessors().isEmpty()) {
+//            out.print(" pred:");
+//            for (Instruction pred : blockPredecessors()) {
+//                out.print(pred.block());
+//            }
+//        }
     }
 
     @Override
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/NegateOp.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/NegateOp.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/NegateOp.java	Fri May 27 19:57:56 2011 +0200
@@ -79,7 +79,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         if (i instanceof NegateOp) {
             NegateOp o = (NegateOp) i;
             return x() == o.x();
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/NullCheck.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/NullCheck.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/NullCheck.java	Fri May 27 19:57:56 2011 +0200
@@ -82,7 +82,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         if (i instanceof NullCheck) {
             NullCheck o = (NullCheck) i;
             return object() == o.object();
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/Op2.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/Op2.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/Op2.java	Fri May 27 19:57:56 2011 +0200
@@ -30,7 +30,7 @@
 /**
  * The {@code Op2} class is the base of arithmetic and logic operations with two inputs.
  */
-public abstract class Op2 extends Instruction {
+public abstract class Op2 extends Value {
 
     private static final int INPUT_COUNT = 2;
     private static final int INPUT_X = 0;
@@ -105,7 +105,7 @@
     }
 
     @Override
-    public boolean valueEqual(Instruction i) {
+    public boolean valueEqual(Node i) {
         if (i instanceof Op2) {
             Op2 o = (Op2) i;
             return opcode == o.opcode && x() == o.x() && y() == o.y();
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/Phi.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/Phi.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/Phi.java	Fri May 27 19:57:56 2011 +0200
@@ -49,7 +49,6 @@
     /**
      * The join block for this phi.
      */
-     @Override
     public Merge block() {
         return (Merge) inputs().get(super.inputCount() + INPUT_BLOCK);
     }
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/ir/Value.java
--- a/graal/GraalCompiler/src/com/sun/c1x/ir/Value.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/Value.java	Fri May 27 19:57:56 2011 +0200
@@ -56,8 +56,6 @@
 
     protected CiValue operand = CiValue.IllegalValue;
 
-    public abstract Merge block();
-
     /**
      * Creates a new value with the specified kind.
      * @param kind the type of this value
@@ -266,6 +264,28 @@
     }
 
     /**
+     * Compute the value number of this Instruction. Local and global value numbering
+     * optimizations use a hash map, and the value number provides a hash code.
+     * If the instruction cannot be value numbered, then this method should return
+     * {@code 0}.
+     * @return the hashcode of this instruction
+     */
+    public int valueNumber() {
+        return 0;
+    }
+
+    /**
+     * Checks that this instruction is equal to another instruction for the purposes
+     * of value numbering.
+     * @param i the other instruction
+     * @return {@code true} if this instruction is equivalent to the specified
+     * instruction w.r.t. value numbering
+     */
+    public boolean valueEqual(Node i) {
+        return false;
+    }
+
+    /**
      * This method supports the visitor pattern by accepting a visitor and calling the
      * appropriate {@code visit()} method.
      *
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/lir/LIRBlock.java
--- a/graal/GraalCompiler/src/com/sun/c1x/lir/LIRBlock.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/lir/LIRBlock.java	Fri May 27 19:57:56 2011 +0200
@@ -277,4 +277,25 @@
     public FrameState lastState() {
         return lastState;
     }
+
+    private Node first;
+    private Node last;
+
+    public Node firstInstruction() {
+        return first;
+    }
+
+
+    public Node lastInstruction() {
+        return last;
+    }
+
+    public void setFirstInstruction(Node n) {
+        first = n;
+    }
+
+
+    public void setLastInstruction(Node n) {
+        last = n;
+    }
 }
diff -r 095162a84dcc -r c3f64b66fc78 graal/GraalCompiler/src/com/sun/c1x/value/FrameState.java
--- a/graal/GraalCompiler/src/com/sun/c1x/value/FrameState.java	Fri May 27 18:44:13 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/value/FrameState.java	Fri May 27 19:57:56 2011 +0200
@@ -445,11 +445,6 @@
     }
 
     @Override
-    public Merge block() {
-        return null;
-    }
-
-    @Override
     public void accept(ValueVisitor v) {
         v.visitFrameState(this);
     }