--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/BlockBegin.java	Wed Apr 27 11:50:44 2011 +0200
@@ -0,0 +1,912 @@
+/*
+ * 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.sun.c1x.ir;
+
+import java.util.*;
+
+import com.sun.c1x.*;
+import com.sun.c1x.asm.*;
+import com.sun.c1x.debug.*;
+import com.sun.c1x.lir.*;
+import com.sun.c1x.util.*;
+import com.sun.c1x.value.*;
+import com.sun.cri.ci.*;
+
+/**
+ * Denotes the beginning of a basic block, and holds information
+ * about the basic block, including the successor and
+ * predecessor blocks, exception handlers, liveness information, etc.
+ *
+ * @author Ben L. Titzer
+ */
+public final class BlockBegin extends Instruction {
+    private static final List<BlockBegin> NO_HANDLERS = Collections.emptyList();
+
+    /**
+     * An enumeration of flags for block entries indicating various things.
+     */
+    public enum BlockFlag {
+        StandardEntry,
+        OsrEntry,
+        ExceptionEntry,
+        SubroutineEntry,
+        BackwardBranchTarget,
+        IsOnWorkList,
+        WasVisited,
+        DefaultExceptionHandler,
+        ParserLoopHeader,
+        CriticalEdgeSplit,
+        LinearScanLoopHeader,
+        LinearScanLoopEnd;
+
+        public final int mask = 1 << ordinal();
+    }
+
+    /**
+     * A unique id used in tracing.
+     */
+    public final int blockID;
+
+    /**
+     * Denotes the current set of {@link BlockBegin.BlockFlag} settings.
+     */
+    private int blockFlags;
+
+    /**
+     * The frame state before execution of the first instruction in this block.
+     */
+    private FrameState stateBefore;
+
+    /**
+     * A link to the last node in the block (which contains the successors).
+     */
+    private BlockEnd end;
+
+    /**
+     * The {@link BlockBegin} nodes for which this node is a successor.
+     */
+    private final List<BlockBegin> predecessors;
+
+    private int depthFirstNumber;
+    private int linearScanNumber;
+    private int loopDepth;
+    private int loopIndex;
+
+    private BlockBegin dominator;
+    private List<BlockBegin> exceptionHandlerBlocks;
+    private List<FrameState> exceptionHandlerStates;
+
+    // LIR block
+    public LIRBlock lirBlock;
+
+    /**
+     * Constructs a new BlockBegin at the specified bytecode index.
+     * @param bci the bytecode index of the start
+     * @param blockID the ID of the block
+     */
+    public BlockBegin(int bci, int blockID) {
+        super(CiKind.Illegal);
+        this.blockID = blockID;
+        depthFirstNumber = -1;
+        linearScanNumber = -1;
+        predecessors = new ArrayList<BlockBegin>(2);
+        loopIndex = -1;
+        setBCI(bci);
+    }
+
+    /**
+     * Gets the list of predecessors of this block.
+     * @return the predecessor list
+     */
+    public List<BlockBegin> predecessors() {
+        return predecessors;
+    }
+
+    /**
+     * Gets the dominator of this block.
+     * @return the dominator block
+     */
+    public BlockBegin dominator() {
+        return dominator;
+    }
+
+    /**
+     * Sets the dominator block for this block.
+     * @param dominator the dominator for this block
+     */
+    public void setDominator(BlockBegin dominator) {
+        this.dominator = dominator;
+    }
+
+    /**
+     * Gets the depth first traversal number of this block.
+     * @return the depth first number
+     */
+    public int depthFirstNumber() {
+        return depthFirstNumber;
+    }
+
+    /**
+     * Gets the linear scan number of this block.
+     * @return the linear scan number
+     */
+    public int linearScanNumber() {
+        return linearScanNumber;
+    }
+
+    /**
+     * Gets the loop depth of this block.
+     * @return the loop depth
+     */
+    public int loopDepth() {
+        return loopDepth;
+    }
+
+    /**
+     * Gets the loop index of this block.
+     * @return the loop index
+     */
+    public int loopIndex() {
+        return loopIndex;
+    }
+
+    /**
+     * Gets the block end associated with this basic block.
+     * @return the block end
+     */
+    public BlockEnd end() {
+        return end;
+    }
+
+    /**
+     * Gets the state at the start of this block.
+     * @return the state at the start of this block
+     */
+    @Override
+    public FrameState stateBefore() {
+        return stateBefore;
+    }
+
+    /**
+     * Sets the initial state for this block.
+     * @param stateBefore the state for this block
+     */
+    public void setStateBefore(FrameState stateBefore) {
+        assert this.stateBefore == null;
+        this.stateBefore = stateBefore;
+    }
+
+    /**
+     * Gets the exception handlers that cover one or more instructions of this basic block.
+     *
+     * @return the exception handlers
+     */
+    public List<BlockBegin> exceptionHandlerBlocks() {
+        return exceptionHandlerBlocks == null ? NO_HANDLERS : exceptionHandlerBlocks;
+    }
+
+    public List<FrameState> exceptionHandlerStates() {
+        return exceptionHandlerStates;
+    }
+
+    public void setDepthFirstNumber(int depthFirstNumber) {
+        assert depthFirstNumber >= 0;
+        this.depthFirstNumber = depthFirstNumber;
+    }
+
+    public void setLinearScanNumber(int linearScanNumber) {
+        this.linearScanNumber = linearScanNumber;
+    }
+
+    public void setLoopDepth(int loopDepth) {
+        this.loopDepth = loopDepth;
+    }
+
+    public void setLoopIndex(int loopIndex) {
+        this.loopIndex = loopIndex;
+    }
+
+    /**
+     * Set the block end for this block begin. This method will
+     * reset this block's successor list and rebuild it to be equivalent
+     * to the successor list of the specified block end.
+     * @param end the new block end for this block begin
+     */
+    public void setEnd(BlockEnd end) {
+        assert end != null;
+        BlockEnd old = this.end;
+        if (old != end) {
+            if (old != null) {
+                // disconnect this block from the old end
+                old.setBegin(null);
+                // disconnect this block from its current successors
+                for (BlockBegin s : old.successors()) {
+                    s.predecessors().remove(this);
+                }
+            }
+            this.end = end;
+            end.setBegin(this);
+            for (BlockBegin s : end.successors()) {
+                s.addPredecessor(this);
+            }
+        }
+    }
+
+    /**
+     * Set a flag on this block.
+     * @param flag the flag to set
+     */
+    public void setBlockFlag(BlockFlag flag) {
+        blockFlags |= flag.mask;
+    }
+
+    /**
+     * Clear a flag on this block.
+     * @param flag the flag to clear
+     */
+    public void clearBlockFlag(BlockFlag flag) {
+        blockFlags &= ~flag.mask;
+    }
+
+    public void copyBlockFlag(BlockBegin other, BlockFlag flag) {
+        setBlockFlag(flag, other.checkBlockFlag(flag));
+    }
+
+    /**
+     * Check whether this block has the specified flag set.
+     * @param flag the flag to test
+     * @return {@code true} if this block has the flag
+     */
+    public boolean checkBlockFlag(BlockFlag flag) {
+        return (blockFlags & flag.mask) != 0;
+    }
+
+    /**
+     * Iterate over this block, its exception handlers, and its successors, in that order.
+     * @param closure the closure to apply to each block
+     */
+    public void iteratePreOrder(BlockClosure closure) {
+        // XXX: identity hash map might be too slow, consider a boolean array or a mark field
+        iterate(new IdentityHashMap<BlockBegin, BlockBegin>(), closure);
+    }
+
+    /**
+     * Iterate over all blocks transitively reachable from this block.
+     * @param closure the closure to apply to each block
+     * @param predecessors {@code true} if also to include this blocks predecessors
+     */
+    public void iterateAnyOrder(BlockClosure closure, boolean predecessors) {
+        IdentityHashMap<BlockBegin, BlockBegin> mark = new IdentityHashMap<BlockBegin, BlockBegin>();
+        LinkedList<BlockBegin> queue = new LinkedList<BlockBegin>();
+        queue.offer(this);
+        mark.put(this, this);
+        BlockBegin block;
+        while ((block = queue.poll()) != null) {
+            closure.apply(block);
+            queueBlocks(queue, block.exceptionHandlerBlocks(), mark);
+            queueBlocks(queue, block.end.successors(), mark);
+            queueBlocks(queue, predecessors ? block.predecessors : null, mark);
+        }
+    }
+
+    private void queueBlocks(LinkedList<BlockBegin> queue, List<BlockBegin> list, IdentityHashMap<BlockBegin, BlockBegin> mark) {
+        if (list != null) {
+            for (BlockBegin b : list) {
+                if (!mark.containsKey(b)) {
+                    queue.offer(b);
+                    mark.put(b, b);
+                }
+            }
+        }
+    }
+
+    private void iterate(IdentityHashMap<BlockBegin, BlockBegin> mark, BlockClosure closure) {
+        if (!mark.containsKey(this)) {
+            mark.put(this, this);
+            closure.apply(this);
+            BlockEnd e = end();
+            if (exceptionHandlerBlocks != null) {
+                iterateReverse(mark, closure, exceptionHandlerBlocks);
+            }
+            assert e != null : "block must have block end";
+            iterateReverse(mark, closure, e.successors());
+        }
+    }
+
+    private void iterateReverse(IdentityHashMap<BlockBegin, BlockBegin> mark, BlockClosure closure, List<BlockBegin> list) {
+        for (int i = list.size() - 1; i >= 0; i--) {
+            list.get(i).iterate(mark, closure);
+        }
+    }
+
+    /**
+     * Adds an exception handler that covers one or more instructions in this block.
+     *
+     * @param handler the entry block for the exception handler to add
+     */
+    public void addExceptionHandler(BlockBegin handler) {
+        assert handler != null && handler.checkBlockFlag(BlockBegin.BlockFlag.ExceptionEntry);
+        if (exceptionHandlerBlocks == null) {
+            exceptionHandlerBlocks = new ArrayList<BlockBegin>(3);
+            exceptionHandlerBlocks.add(handler);
+        } else if (!exceptionHandlerBlocks.contains(handler)) {
+            exceptionHandlerBlocks.add(handler);
+        }
+    }
+
+    /**
+     * Adds a frame state that merges into the exception handler whose entry is this block.
+     *
+     * @param state the frame state at an instruction that raises an exception that can be caught by the exception
+     *            handler represented by this block
+     * @return the index of {@code state} in the list of frame states merging at this block (i.e. the frames states for
+     *         all instruction throwing an exception caught by this exception handler)
+     */
+    public int addExceptionState(FrameState state) {
+        assert checkBlockFlag(BlockBegin.BlockFlag.ExceptionEntry);
+        if (exceptionHandlerStates == null) {
+            exceptionHandlerStates = new ArrayList<FrameState>(4);
+        }
+        exceptionHandlerStates.add(state);
+        return exceptionHandlerStates.size() - 1;
+    }
+
+    /**
+     * Add a predecessor to this block.
+     * @param pred the predecessor to add
+     */
+    public void addPredecessor(BlockBegin pred) {
+        predecessors.add(pred);
+    }
+
+    /**
+     * Removes all occurrences of the specified block from the predecessor list of this block.
+     * @param pred the predecessor to remove
+     */
+    public void removePredecessor(BlockBegin pred) {
+        while (predecessors.remove(pred)) {
+            // the block may appear multiple times in the list
+            // XXX: this is not very efficient, consider Util.removeAllFromList
+        }
+    }
+
+    @Override
+    public void accept(ValueVisitor v) {
+        v.visitBlockBegin(this);
+    }
+
+    public void mergeOrClone(FrameState newState) {
+        FrameState existingState = stateBefore;
+
+        if (existingState == null) {
+            // this is the first state for the block
+            if (wasVisited()) {
+                // this can happen for complex jsr/ret patterns; just bail out
+                throw new CiBailout("jsr/ret too complex");
+            }
+
+            // copy state because it is modified
+            newState = newState.copy();
+
+            if (C1XOptions.UseStackMapTableLiveness) {
+                // if a liveness map is available, use it to invalidate dead locals
+                CiBitMap[] livenessMap = newState.scope().method.livenessMap();
+                if (livenessMap != null && bci() >= 0) {
+                    assert bci() < livenessMap.length;
+                    CiBitMap liveness = livenessMap[bci()];
+                    if (liveness != null) {
+                        invalidateDeadLocals(newState, liveness);
+                    }
+                }
+            }
+
+            // if the block is a loop header, insert all necessary phis
+            if (isParserLoopHeader()) {
+                insertLoopPhis(newState);
+            }
+
+            stateBefore = newState;
+        } else {
+            if (!C1XOptions.AssumeVerifiedBytecode && !existingState.isSameAcrossScopes(newState)) {
+                // stacks or locks do not match--bytecodes would not verify
+                throw new CiBailout("stack or locks do not match");
+            }
+
+            // while (existingState.scope() != newState.scope()) {
+            //     // XXX: original code is not sure if this is necessary
+            //     newState = newState.scope().callerState();
+            //     assert newState != null : "could not match scopes";
+            // }
+            // above code replaced with assert for the moment
+            assert existingState.scope() == newState.scope();
+
+            assert existingState.localsSize() == newState.localsSize();
+            assert existingState.stackSize() == newState.stackSize();
+
+            if (wasVisited() && !isParserLoopHeader()) {
+                throw new CiBailout("jsr/ret too complicated");
+            }
+
+            existingState.merge(this, newState);
+        }
+    }
+
+    private void invalidateDeadLocals(FrameState newState, CiBitMap liveness) {
+        int max = newState.localsSize();
+        assert max <= liveness.size();
+        for (int i = 0; i < max; i++) {
+            Value x = newState.localAt(i);
+            if (x != null) {
+                if (!liveness.get(i)) {
+                    // invalidate the local if it is not live
+                    newState.invalidateLocal(i);
+                }
+            }
+        }
+    }
+
+    private void insertLoopPhis(FrameState newState) {
+        int stackSize = newState.stackSize();
+        for (int i = 0; i < stackSize; i++) {
+            // always insert phis for the stack
+            newState.setupPhiForStack(this, i);
+        }
+        int localsSize = newState.localsSize();
+        CiBitMap requiresPhi = newState.scope().getStoresInLoops();
+        for (int i = 0; i < localsSize; i++) {
+            Value x = newState.localAt(i);
+            if (x != null) {
+                if (requiresPhi != null) {
+                    if (requiresPhi.get(i) || x.kind.isDoubleWord() && requiresPhi.get(i + 1)) {
+                        // selectively do a phi
+                        newState.setupPhiForLocal(this, i);
+                    }
+                } else {
+                    // always setup a phi
+                    newState.setupPhiForLocal(this, i);
+                }
+            }
+        }
+    }
+
+    public boolean isStandardEntry() {
+        return checkBlockFlag(BlockFlag.StandardEntry);
+    }
+
+    public void setStandardEntry() {
+        setBlockFlag(BlockFlag.StandardEntry);
+    }
+
+    public boolean isOsrEntry() {
+        return checkBlockFlag(BlockFlag.OsrEntry);
+    }
+
+    public void setOsrEntry(boolean value) {
+        setBlockFlag(BlockFlag.OsrEntry, value);
+    }
+
+    public boolean isBackwardBranchTarget() {
+        return checkBlockFlag(BlockFlag.BackwardBranchTarget);
+    }
+
+    public void setBackwardBranchTarget(boolean value) {
+        setBlockFlag(BlockFlag.BackwardBranchTarget, value);
+    }
+
+    public boolean isCriticalEdgeSplit() {
+        return checkBlockFlag(BlockFlag.CriticalEdgeSplit);
+    }
+
+    public void setCriticalEdgeSplit(boolean value) {
+        setBlockFlag(BlockFlag.CriticalEdgeSplit, value);
+    }
+
+    public boolean isExceptionEntry() {
+        return checkBlockFlag(BlockFlag.ExceptionEntry);
+    }
+
+    public void setExceptionEntry() {
+        setBlockFlag(BlockFlag.ExceptionEntry);
+    }
+
+    public boolean isSubroutineEntry() {
+        return checkBlockFlag(BlockFlag.SubroutineEntry);
+    }
+
+    public void setSubroutineEntry() {
+        setBlockFlag(BlockFlag.SubroutineEntry);
+    }
+
+    public boolean isOnWorkList() {
+        return checkBlockFlag(BlockFlag.IsOnWorkList);
+    }
+
+    public void setOnWorkList(boolean value) {
+        setBlockFlag(BlockFlag.IsOnWorkList, value);
+    }
+
+    public boolean wasVisited() {
+        return checkBlockFlag(BlockFlag.WasVisited);
+    }
+
+    public void setWasVisited(boolean value) {
+        setBlockFlag(BlockFlag.WasVisited, value);
+    }
+
+    public boolean isParserLoopHeader() {
+        return checkBlockFlag(BlockFlag.ParserLoopHeader);
+    }
+
+    public void setParserLoopHeader(boolean value) {
+        setBlockFlag(BlockFlag.ParserLoopHeader, value);
+    }
+
+    public boolean isLinearScanLoopHeader() {
+        return checkBlockFlag(BlockFlag.LinearScanLoopHeader);
+    }
+
+    public void setLinearScanLoopHeader(boolean value) {
+        setBlockFlag(BlockFlag.LinearScanLoopHeader, value);
+    }
+
+    public boolean isLinearScanLoopEnd() {
+        return checkBlockFlag(BlockFlag.LinearScanLoopEnd);
+    }
+
+    public void setLinearScanLoopEnd(boolean value) {
+        setBlockFlag(BlockFlag.LinearScanLoopEnd, value);
+    }
+
+    private void setBlockFlag(BlockFlag flag, boolean value) {
+        if (value) {
+            setBlockFlag(flag);
+        } else {
+            clearBlockFlag(flag);
+        }
+    }
+
+    public void copyBlockFlags(BlockBegin other) {
+        copyBlockFlag(other, BlockBegin.BlockFlag.ParserLoopHeader);
+        copyBlockFlag(other, BlockBegin.BlockFlag.SubroutineEntry);
+        copyBlockFlag(other, BlockBegin.BlockFlag.ExceptionEntry);
+        copyBlockFlag(other, BlockBegin.BlockFlag.WasVisited);
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder builder = new StringBuilder();
+        builder.append("block #");
+        builder.append(blockID);
+        builder.append(",");
+        builder.append(depthFirstNumber);
+        builder.append(" @ ");
+        builder.append(bci());
+        builder.append(" [");
+        boolean hasFlag = false;
+        for (BlockFlag f : BlockFlag.values()) {
+            if (checkBlockFlag(f)) {
+                if (hasFlag) {
+                    builder.append(' ');
+                }
+                builder.append(f.name());
+                hasFlag = true;
+            }
+        }
+
+        builder.append("]");
+        if (end != null) {
+            builder.append(" -> ");
+            boolean hasSucc = false;
+            for (BlockBegin s : end.successors()) {
+                if (hasSucc) {
+                    builder.append(", ");
+                }
+                builder.append("#");
+                builder.append(s.blockID);
+                hasSucc = true;
+            }
+        }
+        return builder.toString();
+    }
+
+    /**
+     * Get the number of successors.
+     * @return the number of successors
+     */
+    public int numberOfSux() {
+        return end.successors.size();
+    }
+
+    /**
+     * Get the successor at a certain position.
+     * @param i the position
+     * @return the successor
+     */
+    public BlockBegin suxAt(int i) {
+        return end.successors.get(i);
+    }
+
+    /**
+     * Get the number of predecessors.
+     * @return the number of predecessors
+     */
+    public int numberOfPreds() {
+        return predecessors.size();
+    }
+
+    /**
+     * @return the label associated with the block, used by the LIR
+     */
+    public Label label() {
+        return lirBlock().label;
+    }
+
+    public void setLir(LIRList lir) {
+        lirBlock().setLir(lir);
+    }
+
+    public LIRList lir() {
+        return lirBlock().lir();
+    }
+
+    public LIRBlock lirBlock() {
+        if (lirBlock == null) {
+            lirBlock = new LIRBlock();
+        }
+        return lirBlock;
+    }
+
+    public int exceptionHandlerPco() {
+        return lirBlock == null ? 0 : lirBlock.exceptionHandlerPCO;
+    }
+
+    public void setExceptionHandlerPco(int codeOffset) {
+        lirBlock().exceptionHandlerPCO = codeOffset;
+    }
+
+    public int numberOfExceptionHandlers() {
+        return exceptionHandlerBlocks == null ? 0 : exceptionHandlerBlocks.size();
+    }
+
+    public BlockBegin exceptionHandlerAt(int i) {
+        return exceptionHandlerBlocks.get(i);
+    }
+
+    public BlockBegin predAt(int j) {
+        return predecessors.get(j);
+    }
+
+    public int firstLirInstructionId() {
+        return lirBlock.firstLirInstructionID;
+    }
+
+    public void setFirstLirInstructionId(int firstLirInstructionId) {
+        lirBlock.firstLirInstructionID = firstLirInstructionId;
+    }
+
+    public int lastLirInstructionId() {
+        return lirBlock.lastLirInstructionID;
+    }
+
+    public void setLastLirInstructionId(int lastLirInstructionId) {
+        lirBlock.lastLirInstructionID = lastLirInstructionId;
+    }
+
+    public boolean isPredecessor(BlockBegin block) {
+        return this.predecessors.contains(block);
+    }
+
+    public void printWithoutPhis(LogStream out) {
+        // print block id
+        BlockEnd end = end();
+        out.print("B").print(blockID).print(" ");
+
+        // print flags
+        StringBuilder sb = new StringBuilder(8);
+        if (isStandardEntry()) {
+            sb.append('S');
+        }
+        if (isOsrEntry()) {
+            sb.append('O');
+        }
+        if (isExceptionEntry()) {
+            sb.append('E');
+        }
+        if (isSubroutineEntry()) {
+            sb.append('s');
+        }
+        if (isParserLoopHeader()) {
+            sb.append("LH");
+        }
+        if (isBackwardBranchTarget()) {
+            sb.append('b');
+        }
+        if (wasVisited()) {
+            sb.append('V');
+        }
+        if (sb.length() != 0) {
+            out.print('(').print(sb.toString()).print(')');
+        }
+
+        // print block bci range
+        out.print('[').print(bci()).print(", ").print(end == null ? -1 : end.bci()).print(']');
+
+        // print block successors
+        if (end != null && end.successors().size() > 0) {
+            out.print(" .");
+            for (BlockBegin successor : end.successors()) {
+                out.print(" B").print(successor.blockID);
+            }
+        }
+        // print exception handlers
+        if (!exceptionHandlers().isEmpty()) {
+            out.print(" (xhandlers");
+            for (BlockBegin handler : exceptionHandlerBlocks()) {
+                out.print(" B").print(handler.blockID);
+            }
+            out.print(')');
+        }
+
+        // print dominator block
+        if (dominator() != null) {
+            out.print(" dom B").print(dominator().blockID);
+        }
+
+        // print predecessors
+        if (!predecessors().isEmpty()) {
+            out.print(" pred:");
+            for (BlockBegin pred : predecessors()) {
+                out.print(" B").print(pred.blockID);
+            }
+        }
+    }
+
+    @Override
+    public void print(LogStream out) {
+
+        printWithoutPhis(out);
+
+        // print phi functions
+        boolean hasPhisInLocals = false;
+        boolean hasPhisOnStack = false;
+
+        if (end != null && end.stateAfter() != null) {
+            FrameState state = stateBefore();
+
+            int i = 0;
+            while (!hasPhisOnStack && i < state.stackSize()) {
+                Value value = state.stackAt(i);
+                hasPhisOnStack = isPhiAtBlock(value);
+                if (value != null && !value.isIllegal()) {
+                    i += value.kind.sizeInSlots();
+                } else {
+                    i++;
+                }
+            }
+
+            do {
+                for (i = 0; !hasPhisInLocals && i < state.localsSize();) {
+                    Value value = state.localAt(i);
+                    hasPhisInLocals = isPhiAtBlock(value);
+                    // also ignore illegal HiWords
+                    if (value != null && !value.isIllegal()) {
+                        i += value.kind.sizeInSlots();
+                    } else {
+                        i++;
+                    }
+                }
+                state = state.callerState();
+            } while (state != null);
+        }
+
+        // print values in locals
+        if (hasPhisInLocals) {
+            out.println();
+            out.println("Locals:");
+
+            FrameState state = stateBefore();
+            do {
+                int i = 0;
+                while (i < state.localsSize()) {
+                    Value value = state.localAt(i);
+                    if (value != null) {
+                        out.println(stateString(i, value));
+                        // also ignore illegal HiWords
+                        i += value.isIllegal() ? 1 : value.kind.sizeInSlots();
+                    } else {
+                        i++;
+                    }
+                }
+                out.println();
+                state = state.callerState();
+            } while (state != null);
+        }
+
+        // print values on stack
+        if (hasPhisOnStack) {
+            out.println();
+            out.println("Stack:");
+            int i = 0;
+            while (i < stateBefore().stackSize()) {
+                Value value = stateBefore().stackAt(i);
+                if (value != null) {
+                    out.println(stateString(i, value));
+                    i += value.kind.sizeInSlots();
+                } else {
+                    i++;
+                }
+            }
+        }
+
+    }
+
+
+
+    /**
+     * Determines if a given instruction is a phi whose {@linkplain Phi#block() join block} is a given block.
+     *
+     * @param value the instruction to test
+     * @param block the block that may be the join block of {@code value} if {@code value} is a phi
+     * @return {@code true} if {@code value} is a phi and its join block is {@code block}
+     */
+    private boolean isPhiAtBlock(Value value) {
+        return value instanceof Phi && ((Phi) value).block() == this;
+    }
+
+
+    /**
+     * Formats a given instruction as a value in a {@linkplain FrameState frame state}. If the instruction is a phi defined at a given
+     * block, its {@linkplain Phi#inputCount() inputs} are appended to the returned string.
+     *
+     * @param index the index of the value in the frame state
+     * @param value the frame state value
+     * @param block if {@code value} is a phi, then its inputs are formatted if {@code block} is its
+     *            {@linkplain Phi#block() join point}
+     * @return the instruction representation as a string
+     */
+    public String stateString(int index, Value value) {
+        StringBuilder sb = new StringBuilder(30);
+        sb.append(String.format("%2d  %s", index, Util.valueString(value)));
+        if (value instanceof Phi) {
+            Phi phi = (Phi) value;
+            // print phi operands
+            if (phi.block() == this) {
+                sb.append(" [");
+                for (int j = 0; j < phi.inputCount(); j++) {
+                    sb.append(' ');
+                    Value operand = phi.inputAt(j);
+                    if (operand != null) {
+                        sb.append(Util.valueString(operand));
+                    } else {
+                        sb.append("NULL");
+                    }
+                }
+                sb.append("] ");
+            }
+        }
+        if (value != null && value.hasSubst()) {
+            sb.append("alias ").append(Util.valueString(value.subst()));
+        }
+        return sb.toString();
+    }
+}