Mercurial > hg > truffle

changeset 2942:c20600a46188

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Merge.
author Thomas Wuerthinger <thomas@wuerthinger.net>
date Thu, 09 Jun 2011 17:29:11 +0200
parents cd4176d590e7 (diff) 0e3ec0a4eda4 (current diff)
children 3891afa020da
files graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/phases/GraphBuilderPhase.java graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/phases/InliningPhase.java
diffstat 14 files changed, 313 insertions(+), 208 deletions(-) [+]
line wrap: on
line diff
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/gen/LIRGenerator.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/gen/LIRGenerator.java	Thu Jun 09 17:29:11 2011 +0200
@@ -397,6 +397,9 @@
 
         DeoptimizationStub stub = new DeoptimizationStub(state);
         deoptimizationStubs.add(stub);
+
+        emitCompare(x.node());
+        //emitBranch(x.node(), stub.label)
         throw new RuntimeException();
         //lir.branch(x.condition.negate(), stub.label, stub.info);
     }
@@ -681,10 +684,14 @@
     }
 
     @Override
-    public void visitNullCheck(FixedNullCheck x) {
-        CiValue value = load(x.object());
-        LIRDebugInfo info = stateFor(x);
-        lir.nullCheck(value, info);
+    public void visitFixedGuard(FixedGuard fixedGuard) {
+        Node comp = fixedGuard.node();
+        if (comp instanceof IsNonNull) {
+            IsNonNull x = (IsNonNull) comp;
+            CiValue value = load(x.object());
+            LIRDebugInfo info = stateFor(x);
+            lir.nullCheck(value, info);
+        }
     }
 
     @Override
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/AccessField.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/AccessField.java	Thu Jun 09 17:29:11 2011 +0200
@@ -74,6 +74,8 @@
         super(kind, inputCount + INPUT_COUNT, successorCount + SUCCESSOR_COUNT, graph);
         this.field = field;
         setObject(object);
+        assert field.isResolved();
+        assert field.holder().isResolved();
     }
 
     /**
@@ -93,18 +95,10 @@
     }
 
     /**
-     * Checks whether the class of the field of this access is loaded.
-     * @return {@code true} if the class is loaded
-     */
-    public boolean isLoaded() {
-        return field.isResolved();
-    }
-
-    /**
      * Checks whether this field is declared volatile.
      * @return {@code true} if the field is resolved and declared volatile
      */
     public boolean isVolatile() {
-        return isLoaded() && Modifier.isVolatile(field.accessFlags());
+        return Modifier.isVolatile(field.accessFlags());
     }
 }
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/ArrayLength.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/ArrayLength.java	Thu Jun 09 17:29:11 2011 +0200
@@ -126,9 +126,7 @@
                 return length;
             }
             CiConstant constantValue = null;
-            if (array instanceof LoadField) {
-                constantValue = ((LoadField) array).constantValue();
-            } else if (array.isConstant()) {
+            if (array.isConstant()) {
                 constantValue = array.asConstant();
             }
             if (constantValue != null && constantValue.isNonNull()) {
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/ClipNode.java	Thu Jun 09 15:25:27 2011 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,65 +0,0 @@
-/*
- * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- */
-package com.oracle.max.graal.compiler.ir;
-
-import com.oracle.max.graal.compiler.debug.*;
-import com.oracle.max.graal.graph.*;
-import com.sun.cri.ci.*;
-
-
-public final class ClipNode extends Instruction {
-    private static final int INPUT_COUNT = 1;
-    private static final int INPUT_NODE = 0;
-
-    private static final int SUCCESSOR_COUNT = 0;
-
-    /**
-     * The instruction that produces the object tested against null.
-     */
-     public FloatingNode node() {
-        return (FloatingNode) inputs().get(super.inputCount() + INPUT_NODE);
-    }
-
-    public FloatingNode setNode(FloatingNode n) {
-        return (FloatingNode) inputs().set(super.inputCount() + INPUT_NODE, n);
-    }
-
-    public ClipNode(Graph graph) {
-        super(CiKind.Illegal, INPUT_COUNT, SUCCESSOR_COUNT, graph);
-    }
-
-    @Override
-    public void accept(ValueVisitor v) {
-        // Do nothing.
-    }
-
-    @Override
-    public void print(LogStream out) {
-        out.print("clip node ").print(node());
-    }
-
-    @Override
-    public Node copy(Graph into) {
-        return new ClipNode(into);
-    }
-}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/FixedGuard.java	Thu Jun 09 17:29:11 2011 +0200
@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.max.graal.compiler.ir;
+
+import com.oracle.max.graal.compiler.debug.*;
+import com.oracle.max.graal.graph.*;
+import com.sun.cri.ci.*;
+
+
+public final class FixedGuard extends Instruction {
+    private static final int INPUT_COUNT = 1;
+    private static final int INPUT_NODE = 0;
+
+    private static final int SUCCESSOR_COUNT = 0;
+
+    /**
+     * The instruction that produces the object tested against null.
+     */
+     public FloatingNode node() {
+        return (FloatingNode) inputs().get(super.inputCount() + INPUT_NODE);
+    }
+
+    public FloatingNode setNode(FloatingNode n) {
+        return (FloatingNode) inputs().set(super.inputCount() + INPUT_NODE, n);
+    }
+
+    public FixedGuard(Graph graph) {
+        super(CiKind.Illegal, INPUT_COUNT, SUCCESSOR_COUNT, graph);
+    }
+
+    @Override
+    public void accept(ValueVisitor v) {
+        v.visitFixedGuard(this);
+    }
+
+    @Override
+    public void print(LogStream out) {
+        out.print("clip node ").print(node());
+    }
+
+    @Override
+    public Node copy(Graph into) {
+        return new FixedGuard(into);
+    }
+}
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/FixedNullCheck.java	Thu Jun 09 15:25:27 2011 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,115 +0,0 @@
-/*
- * Copyright (c) 2009, 2011, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- */
-package com.oracle.max.graal.compiler.ir;
-
-import com.oracle.max.graal.compiler.debug.*;
-import com.oracle.max.graal.compiler.util.*;
-import com.oracle.max.graal.graph.*;
-import com.sun.cri.bytecode.*;
-import com.sun.cri.ci.*;
-import com.sun.cri.ri.*;
-
-/**
- * The {@code NullCheck} class represents an explicit null check instruction.
- */
-public final class FixedNullCheck extends Instruction {
-
-    private static final int INPUT_COUNT = 1;
-    private static final int INPUT_OBJECT = 0;
-
-    private static final int SUCCESSOR_COUNT = 0;
-
-    @Override
-    protected int inputCount() {
-        return super.inputCount() + INPUT_COUNT;
-    }
-
-    @Override
-    protected int successorCount() {
-        return super.successorCount() + SUCCESSOR_COUNT;
-    }
-
-    /**
-     * The instruction that produces the object tested against null.
-     */
-     public Value object() {
-        return (Value) inputs().get(super.inputCount() + INPUT_OBJECT);
-    }
-
-    public Value setObject(Value n) {
-        return (Value) inputs().set(super.inputCount() + INPUT_OBJECT, n);
-    }
-
-    /**
-     * Constructs a new NullCheck instruction.
-     * @param object the instruction producing the object to check against null
-     * @param stateBefore the state before executing the null check
-     * @param graph
-     */
-    public FixedNullCheck(Value object, Graph graph) {
-        super(CiKind.Object, INPUT_COUNT, SUCCESSOR_COUNT, graph);
-        assert object == null || object.kind == CiKind.Object;
-        setObject(object);
-    }
-
-    @Override
-    public void accept(ValueVisitor v) {
-        v.visitNullCheck(this);
-    }
-
-    @Override
-    public int valueNumber() {
-        return Util.hash1(Bytecodes.IFNONNULL, object());
-    }
-
-    @Override
-    public boolean valueEqual(Node i) {
-        if (i instanceof FixedNullCheck) {
-            FixedNullCheck o = (FixedNullCheck) i;
-            return object() == o.object();
-        }
-        return false;
-    }
-
-    @Override
-    public RiType declaredType() {
-        // null check does not alter the type of the object
-        return object().declaredType();
-    }
-
-    @Override
-    public RiType exactType() {
-        // null check does not alter the type of the object
-        return object().exactType();
-    }
-
-    @Override
-    public void print(LogStream out) {
-        out.print("null_check(").print(object()).print(')');
-    }
-
-    @Override
-    public Node copy(Graph into) {
-        return new FixedNullCheck(null, into);
-    }
-}
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/GuardNode.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/GuardNode.java	Thu Jun 09 17:29:11 2011 +0200
@@ -36,12 +36,12 @@
     /**
      * The instruction that produces the object tested against null.
      */
-     public FloatingNode node() {
-        return (FloatingNode) inputs().get(super.inputCount() + INPUT_NODE);
+     public Compare node() {
+        return (Compare) inputs().get(super.inputCount() + INPUT_NODE);
     }
 
-    public FloatingNode setNode(FloatingNode n) {
-        return (FloatingNode) inputs().set(super.inputCount() + INPUT_NODE, n);
+    public Compare setNode(Compare n) {
+        return (Compare) inputs().set(super.inputCount() + INPUT_NODE, n);
     }
 
     public GuardNode(Graph graph) {
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/IsNonNull.java	Thu Jun 09 17:29:11 2011 +0200
@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2009, 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.max.graal.compiler.ir;
+
+import com.oracle.max.graal.compiler.debug.*;
+import com.oracle.max.graal.compiler.util.*;
+import com.oracle.max.graal.graph.*;
+import com.sun.cri.bytecode.*;
+import com.sun.cri.ci.*;
+import com.sun.cri.ri.*;
+
+/**
+ * The {@code NullCheck} class represents an explicit null check instruction.
+ */
+public final class IsNonNull extends FloatingNode {
+
+    private static final int INPUT_COUNT = 1;
+    private static final int INPUT_OBJECT = 0;
+
+    private static final int SUCCESSOR_COUNT = 0;
+
+    @Override
+    protected int inputCount() {
+        return super.inputCount() + INPUT_COUNT;
+    }
+
+    @Override
+    protected int successorCount() {
+        return super.successorCount() + SUCCESSOR_COUNT;
+    }
+
+    /**
+     * The instruction that produces the object tested against null.
+     */
+     public Value object() {
+        return (Value) inputs().get(super.inputCount() + INPUT_OBJECT);
+    }
+
+    public Value setObject(Value n) {
+        return (Value) inputs().set(super.inputCount() + INPUT_OBJECT, n);
+    }
+
+    /**
+     * Constructs a new NullCheck instruction.
+     * @param object the instruction producing the object to check against null
+     * @param stateBefore the state before executing the null check
+     * @param graph
+     */
+    public IsNonNull(Value object, Graph graph) {
+        super(CiKind.Object, INPUT_COUNT, SUCCESSOR_COUNT, graph);
+        assert object == null || object.kind == CiKind.Object;
+        setObject(object);
+    }
+
+    @Override
+    public void accept(ValueVisitor v) {
+        // Nothing to do.
+    }
+
+    @Override
+    public int valueNumber() {
+        return Util.hash1(Bytecodes.IFNONNULL, object());
+    }
+
+    @Override
+    public boolean valueEqual(Node i) {
+        if (i instanceof IsNonNull) {
+            IsNonNull o = (IsNonNull) i;
+            return object() == o.object();
+        }
+        return false;
+    }
+
+    @Override
+    public RiType declaredType() {
+        // null check does not alter the type of the object
+        return object().declaredType();
+    }
+
+    @Override
+    public RiType exactType() {
+        // null check does not alter the type of the object
+        return object().exactType();
+    }
+
+    @Override
+    public void print(LogStream out) {
+        out.print("null_check(").print(object()).print(')');
+    }
+
+    @Override
+    public Node copy(Graph into) {
+        return new IsNonNull(null, into);
+    }
+}
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/LoadField.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/LoadField.java	Thu Jun 09 17:29:11 2011 +0200
@@ -68,8 +68,8 @@
      */
     @Override
     public RiType exactType() {
-        RiType declaredType = declaredType();
-        return declaredType.isResolved() ? declaredType.exactType() : null;
+        RiType declared = declaredType();
+        return declared != null && declared.isResolved() ? declared.exactType() : null;
     }
 
     @Override
@@ -97,7 +97,7 @@
      *
      * @return {@code null} if this load cannot be reduced to a constant
      */
-    public CiConstant constantValue() {
+    private CiConstant constantValue() {
         if (isStatic()) {
             return field.constantValue(null);
         } else if (object().isConstant()) {
@@ -108,8 +108,7 @@
 
     @Override
     public Node copy(Graph into) {
-        LoadField x = new LoadField(null, field, into);
-        return x;
+        return new LoadField(null, field, into);
     }
 
     @SuppressWarnings("unchecked")
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/ValueVisitor.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/ValueVisitor.java	Thu Jun 09 17:29:11 2011 +0200
@@ -58,7 +58,7 @@
     public abstract void visitNewMultiArray(NewMultiArray i);
     public abstract void visitNewObjectArray(NewObjectArray i);
     public abstract void visitNewTypeArray(NewTypeArray i);
-    public abstract void visitNullCheck(FixedNullCheck i);
+    public abstract void visitFixedGuard(FixedGuard fixedGuard);
     public abstract void visitPhi(Phi i);
     public abstract void visitRegisterFinalizer(RegisterFinalizer i);
     public abstract void visitReturn(Return i);
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/phases/GraphBuilderPhase.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/phases/GraphBuilderPhase.java	Thu Jun 09 17:29:11 2011 +0200
@@ -680,7 +680,9 @@
 
     private void genThrow(int bci) {
         Value exception = frameState.apop();
-        append(new FixedNullCheck(exception, graph));
+        FixedGuard node = new FixedGuard(graph);
+        node.setNode(new IsNonNull(exception, graph));
+        append(node);
 
         Instruction entry = handleException(exception, bci);
         if (entry != null) {
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/phases/InliningPhase.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/phases/InliningPhase.java	Thu Jun 09 17:29:11 2011 +0200
@@ -239,7 +239,9 @@
         assert invoke.predecessors().size() == 1 : "size: " + invoke.predecessors().size();
         Instruction pred;
         if (withReceiver) {
-            pred = new FixedNullCheck(parameters[0], compilation.graph);
+            FixedGuard clipNode = new FixedGuard(compilation.graph);
+            clipNode.setNode(new IsNonNull(parameters[0], compilation.graph));
+            pred = clipNode;
         } else {
             pred = new Merge(compilation.graph);
         }
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/phases/LoweringPhase.java	Thu Jun 09 17:29:11 2011 +0200
@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.max.graal.compiler.phases;
+
+import java.util.*;
+
+import com.oracle.max.graal.compiler.*;
+import com.oracle.max.graal.compiler.ir.*;
+import com.oracle.max.graal.compiler.schedule.*;
+import com.oracle.max.graal.graph.*;
+
+public class LoweringPhase extends Phase {
+    @Override
+    protected void run(Graph graph) {
+        NodeMap<Node> javaBlockNodes = graph.createNodeMap();
+        NodeBitMap nodeBitMap = graph.createNodeBitMap();
+        for (Node n : graph.getNodes()) {
+            if (n instanceof FixedNode) {
+                LoweringOp op = n.lookup(LoweringOp.class);
+                if (op != null) {
+                    Node javaBlockNode = getJavaBlockNode(javaBlockNodes, n, nodeBitMap);
+                }
+            }
+
+        }
+    }
+
+    private Node getJavaBlockNode(NodeMap<Node> javaBlockNodes, Node n, NodeBitMap nodeBitMap) {
+        assert n instanceof FixedNode;
+        if (javaBlockNodes.get(n) == null) {
+
+            Node truePred = null;
+            int count = 0;
+            for (Node pred : n.predecessors()) {
+                if (pred instanceof FixedNode) {
+                    truePred = pred;
+                    count++;
+                }
+            }
+
+            assert count > 0;
+            if (count == 1) {
+                if (Schedule.trueSuccessorCount(truePred) == 1) {
+                    javaBlockNodes.set(n, getJavaBlockNode(javaBlockNodes, truePred, nodeBitMap));
+                } else {
+                    // Single predecessor is a split => we are our own block node.
+                    javaBlockNodes.set(n, n);
+                }
+            } else {
+                Node dominator = null;
+                for (Node pred : n.predecessors()) {
+                    if (pred instanceof FixedNode) {
+                       dominator = getCommonDominator(dominator, pred, nodeBitMap);
+                    }
+                }
+            }
+        }
+
+        assert Schedule.truePredecessorCount(javaBlockNodes.get(n)) == 1;
+        return javaBlockNodes.get(n);
+    }
+
+    private Node getCommonDominator(Node a, Node b, NodeBitMap map) {
+        if (a == null) {
+            return b;
+        }
+
+        if (b == null) {
+            return a;
+        }
+
+
+        map.clearAll();
+    }
+
+    public interface LoweringOp extends Op {
+        Node lower(Node node);
+    }
+}
--- a/graal/com.oracle.max.graal.graph/src/com/oracle/max/graal/graph/NodeBitMap.java	Thu Jun 09 15:25:27 2011 +0200
+++ b/graal/com.oracle.max.graal.graph/src/com/oracle/max/graal/graph/NodeBitMap.java	Thu Jun 09 17:29:11 2011 +0200
@@ -65,6 +65,10 @@
         check(node);
         bitMap.clear(node.id());
     }
+    
+    public void clearAll() {
+        bitMap.clearAll();
+    }
 
     private void check(Node node) {
         assert node.graph == graph : "this node is not part of the graph";