Merge WebKit at r75315: Initial merge by git.

Change-Id: I570314b346ce101c935ed22a626b48c2af266b84

12 files changed, 4348 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/bytecode/CodeBlock.cpp b/Source/JavaScriptCore/bytecode/CodeBlock.cpp
new file mode 100644
index 0000000..cbae990
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/CodeBlock.cpp
@@ -0,0 +1,1708 @@
+/*
+ * Copyright (C) 2008, 2009, 2010 Apple Inc. All rights reserved.
+ * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "CodeBlock.h"
+
+#include "BytecodeGenerator.h"
+#include "Debugger.h"
+#include "Interpreter.h"
+#include "JIT.h"
+#include "JSActivation.h"
+#include "JSFunction.h"
+#include "JSStaticScopeObject.h"
+#include "JSValue.h"
+#include "UStringConcatenate.h"
+#include <stdio.h>
+#include <wtf/StringExtras.h>
+
+#define DUMP_CODE_BLOCK_STATISTICS 0
+
+namespace JSC {
+
+#if !defined(NDEBUG) || ENABLE(OPCODE_SAMPLING)
+
+static UString escapeQuotes(const UString& str)
+{
+    UString result = str;
+    size_t pos = 0;
+    while ((pos = result.find('\"', pos)) != notFound) {
+        result = makeUString(result.substringSharingImpl(0, pos), "\"\\\"\"", result.substringSharingImpl(pos + 1));
+        pos += 4;
+    }
+    return result;
+}
+
+static UString valueToSourceString(ExecState* exec, JSValue val)
+{
+    if (!val)
+        return "0";
+
+    if (val.isString())
+        return makeUString("\"", escapeQuotes(val.toString(exec)), "\"");
+
+    return val.toString(exec);
+}
+
+static CString constantName(ExecState* exec, int k, JSValue value)
+{
+    return makeUString(valueToSourceString(exec, value), "(@k", UString::number(k - FirstConstantRegisterIndex), ")").utf8();
+}
+
+static CString idName(int id0, const Identifier& ident)
+{
+    return makeUString(ident.ustring(), "(@id", UString::number(id0), ")").utf8();
+}
+
+CString CodeBlock::registerName(ExecState* exec, int r) const
+{
+    if (r == missingThisObjectMarker())
+        return "<null>";
+
+    if (isConstantRegisterIndex(r))
+        return constantName(exec, r, getConstant(r));
+
+    return makeUString("r", UString::number(r)).utf8();
+}
+
+static UString regexpToSourceString(RegExp* regExp)
+{
+    char postfix[5] = { '/', 0, 0, 0, 0 };
+    int index = 1;
+    if (regExp->global())
+        postfix[index++] = 'g';
+    if (regExp->ignoreCase())
+        postfix[index++] = 'i';
+    if (regExp->multiline())
+        postfix[index] = 'm';
+
+    return makeUString("/", regExp->pattern(), postfix);
+}
+
+static CString regexpName(int re, RegExp* regexp)
+{
+    return makeUString(regexpToSourceString(regexp), "(@re", UString::number(re), ")").utf8();
+}
+
+static UString pointerToSourceString(void* p)
+{
+    char buffer[2 + 2 * sizeof(void*) + 1]; // 0x [two characters per byte] \0
+    snprintf(buffer, sizeof(buffer), "%p", p);
+    return buffer;
+}
+
+NEVER_INLINE static const char* debugHookName(int debugHookID)
+{
+    switch (static_cast<DebugHookID>(debugHookID)) {
+        case DidEnterCallFrame:
+            return "didEnterCallFrame";
+        case WillLeaveCallFrame:
+            return "willLeaveCallFrame";
+        case WillExecuteStatement:
+            return "willExecuteStatement";
+        case WillExecuteProgram:
+            return "willExecuteProgram";
+        case DidExecuteProgram:
+            return "didExecuteProgram";
+        case DidReachBreakpoint:
+            return "didReachBreakpoint";
+    }
+
+    ASSERT_NOT_REACHED();
+    return "";
+}
+
+void CodeBlock::printUnaryOp(ExecState* exec, int location, Vector<Instruction>::const_iterator& it, const char* op) const
+{
+    int r0 = (++it)->u.operand;
+    int r1 = (++it)->u.operand;
+
+    printf("[%4d] %s\t\t %s, %s\n", location, op, registerName(exec, r0).data(), registerName(exec, r1).data());
+}
+
+void CodeBlock::printBinaryOp(ExecState* exec, int location, Vector<Instruction>::const_iterator& it, const char* op) const
+{
+    int r0 = (++it)->u.operand;
+    int r1 = (++it)->u.operand;
+    int r2 = (++it)->u.operand;
+    printf("[%4d] %s\t\t %s, %s, %s\n", location, op, registerName(exec, r0).data(), registerName(exec, r1).data(), registerName(exec, r2).data());
+}
+
+void CodeBlock::printConditionalJump(ExecState* exec, const Vector<Instruction>::const_iterator&, Vector<Instruction>::const_iterator& it, int location, const char* op) const
+{
+    int r0 = (++it)->u.operand;
+    int offset = (++it)->u.operand;
+    printf("[%4d] %s\t\t %s, %d(->%d)\n", location, op, registerName(exec, r0).data(), offset, location + offset);
+}
+
+void CodeBlock::printGetByIdOp(ExecState* exec, int location, Vector<Instruction>::const_iterator& it, const char* op) const
+{
+    int r0 = (++it)->u.operand;
+    int r1 = (++it)->u.operand;
+    int id0 = (++it)->u.operand;
+    printf("[%4d] %s\t %s, %s, %s\n", location, op, registerName(exec, r0).data(), registerName(exec, r1).data(), idName(id0, m_identifiers[id0]).data());
+    it += 4;
+}
+
+void CodeBlock::printPutByIdOp(ExecState* exec, int location, Vector<Instruction>::const_iterator& it, const char* op) const
+{
+    int r0 = (++it)->u.operand;
+    int id0 = (++it)->u.operand;
+    int r1 = (++it)->u.operand;
+    printf("[%4d] %s\t %s, %s, %s\n", location, op, registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data(), registerName(exec, r1).data());
+    it += 5;
+}
+
+#if ENABLE(JIT)
+static bool isGlobalResolve(OpcodeID opcodeID)
+{
+    return opcodeID == op_resolve_global || opcodeID == op_resolve_global_dynamic;
+}
+
+static bool isPropertyAccess(OpcodeID opcodeID)
+{
+    switch (opcodeID) {
+        case op_get_by_id_self:
+        case op_get_by_id_proto:
+        case op_get_by_id_chain:
+        case op_get_by_id_self_list:
+        case op_get_by_id_proto_list:
+        case op_put_by_id_transition:
+        case op_put_by_id_replace:
+        case op_get_by_id:
+        case op_put_by_id:
+        case op_get_by_id_generic:
+        case op_put_by_id_generic:
+        case op_get_array_length:
+        case op_get_string_length:
+            return true;
+        default:
+            return false;
+    }
+}
+
+static unsigned instructionOffsetForNth(ExecState* exec, const Vector<Instruction>& instructions, int nth, bool (*predicate)(OpcodeID))
+{
+    size_t i = 0;
+    while (i < instructions.size()) {
+        OpcodeID currentOpcode = exec->interpreter()->getOpcodeID(instructions[i].u.opcode);
+        if (predicate(currentOpcode)) {
+            if (!--nth)
+                return i;
+        }
+        i += opcodeLengths[currentOpcode];
+    }
+
+    ASSERT_NOT_REACHED();
+    return 0;
+}
+
+static void printGlobalResolveInfo(const GlobalResolveInfo& resolveInfo, unsigned instructionOffset)
+{
+    printf("  [%4d] %s: %s\n", instructionOffset, "resolve_global", pointerToSourceString(resolveInfo.structure).utf8().data());
+}
+
+static void printStructureStubInfo(const StructureStubInfo& stubInfo, unsigned instructionOffset)
+{
+    switch (stubInfo.accessType) {
+    case access_get_by_id_self:
+        printf("  [%4d] %s: %s\n", instructionOffset, "get_by_id_self", pointerToSourceString(stubInfo.u.getByIdSelf.baseObjectStructure).utf8().data());
+        return;
+    case access_get_by_id_proto:
+        printf("  [%4d] %s: %s, %s\n", instructionOffset, "get_by_id_proto", pointerToSourceString(stubInfo.u.getByIdProto.baseObjectStructure).utf8().data(), pointerToSourceString(stubInfo.u.getByIdProto.prototypeStructure).utf8().data());
+        return;
+    case access_get_by_id_chain:
+        printf("  [%4d] %s: %s, %s\n", instructionOffset, "get_by_id_chain", pointerToSourceString(stubInfo.u.getByIdChain.baseObjectStructure).utf8().data(), pointerToSourceString(stubInfo.u.getByIdChain.chain).utf8().data());
+        return;
+    case access_get_by_id_self_list:
+        printf("  [%4d] %s: %s (%d)\n", instructionOffset, "op_get_by_id_self_list", pointerToSourceString(stubInfo.u.getByIdSelfList.structureList).utf8().data(), stubInfo.u.getByIdSelfList.listSize);
+        return;
+    case access_get_by_id_proto_list:
+        printf("  [%4d] %s: %s (%d)\n", instructionOffset, "op_get_by_id_proto_list", pointerToSourceString(stubInfo.u.getByIdProtoList.structureList).utf8().data(), stubInfo.u.getByIdProtoList.listSize);
+        return;
+    case access_put_by_id_transition:
+        printf("  [%4d] %s: %s, %s, %s\n", instructionOffset, "put_by_id_transition", pointerToSourceString(stubInfo.u.putByIdTransition.previousStructure).utf8().data(), pointerToSourceString(stubInfo.u.putByIdTransition.structure).utf8().data(), pointerToSourceString(stubInfo.u.putByIdTransition.chain).utf8().data());
+        return;
+    case access_put_by_id_replace:
+        printf("  [%4d] %s: %s\n", instructionOffset, "put_by_id_replace", pointerToSourceString(stubInfo.u.putByIdReplace.baseObjectStructure).utf8().data());
+        return;
+    case access_get_by_id:
+        printf("  [%4d] %s\n", instructionOffset, "get_by_id");
+        return;
+    case access_put_by_id:
+        printf("  [%4d] %s\n", instructionOffset, "put_by_id");
+        return;
+    case access_get_by_id_generic:
+        printf("  [%4d] %s\n", instructionOffset, "op_get_by_id_generic");
+        return;
+    case access_put_by_id_generic:
+        printf("  [%4d] %s\n", instructionOffset, "op_put_by_id_generic");
+        return;
+    case access_get_array_length:
+        printf("  [%4d] %s\n", instructionOffset, "op_get_array_length");
+        return;
+    case access_get_string_length:
+        printf("  [%4d] %s\n", instructionOffset, "op_get_string_length");
+        return;
+    default:
+        ASSERT_NOT_REACHED();
+    }
+}
+#endif
+
+void CodeBlock::printStructure(const char* name, const Instruction* vPC, int operand) const
+{
+    unsigned instructionOffset = vPC - m_instructions.begin();
+    printf("  [%4d] %s: %s\n", instructionOffset, name, pointerToSourceString(vPC[operand].u.structure).utf8().data());
+}
+
+void CodeBlock::printStructures(const Instruction* vPC) const
+{
+    Interpreter* interpreter = m_globalData->interpreter;
+    unsigned instructionOffset = vPC - m_instructions.begin();
+
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id)) {
+        printStructure("get_by_id", vPC, 4);
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_self)) {
+        printStructure("get_by_id_self", vPC, 4);
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_proto)) {
+        printf("  [%4d] %s: %s, %s\n", instructionOffset, "get_by_id_proto", pointerToSourceString(vPC[4].u.structure).utf8().data(), pointerToSourceString(vPC[5].u.structure).utf8().data());
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_transition)) {
+        printf("  [%4d] %s: %s, %s, %s\n", instructionOffset, "put_by_id_transition", pointerToSourceString(vPC[4].u.structure).utf8().data(), pointerToSourceString(vPC[5].u.structure).utf8().data(), pointerToSourceString(vPC[6].u.structureChain).utf8().data());
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_chain)) {
+        printf("  [%4d] %s: %s, %s\n", instructionOffset, "get_by_id_chain", pointerToSourceString(vPC[4].u.structure).utf8().data(), pointerToSourceString(vPC[5].u.structureChain).utf8().data());
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id)) {
+        printStructure("put_by_id", vPC, 4);
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_replace)) {
+        printStructure("put_by_id_replace", vPC, 4);
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_resolve_global)) {
+        printStructure("resolve_global", vPC, 4);
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_resolve_global_dynamic)) {
+        printStructure("resolve_global_dynamic", vPC, 4);
+        return;
+    }
+
+    // These m_instructions doesn't ref Structures.
+    ASSERT(vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_generic) || vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_generic) || vPC[0].u.opcode == interpreter->getOpcode(op_call) || vPC[0].u.opcode == interpreter->getOpcode(op_call_eval) || vPC[0].u.opcode == interpreter->getOpcode(op_construct));
+}
+
+void CodeBlock::dump(ExecState* exec) const
+{
+    if (m_instructions.isEmpty()) {
+        printf("No instructions available.\n");
+        return;
+    }
+
+    size_t instructionCount = 0;
+
+    for (size_t i = 0; i < m_instructions.size(); i += opcodeLengths[exec->interpreter()->getOpcodeID(m_instructions[i].u.opcode)])
+        ++instructionCount;
+
+    printf("%lu m_instructions; %lu bytes at %p; %d parameter(s); %d callee register(s)\n\n",
+        static_cast<unsigned long>(instructionCount),
+        static_cast<unsigned long>(m_instructions.size() * sizeof(Instruction)),
+        this, m_numParameters, m_numCalleeRegisters);
+
+    Vector<Instruction>::const_iterator begin = m_instructions.begin();
+    Vector<Instruction>::const_iterator end = m_instructions.end();
+    for (Vector<Instruction>::const_iterator it = begin; it != end; ++it)
+        dump(exec, begin, it);
+
+    if (!m_identifiers.isEmpty()) {
+        printf("\nIdentifiers:\n");
+        size_t i = 0;
+        do {
+            printf("  id%u = %s\n", static_cast<unsigned>(i), m_identifiers[i].ustring().utf8().data());
+            ++i;
+        } while (i != m_identifiers.size());
+    }
+
+    if (!m_constantRegisters.isEmpty()) {
+        printf("\nConstants:\n");
+        unsigned registerIndex = m_numVars;
+        size_t i = 0;
+        do {
+            printf("   k%u = %s\n", registerIndex, valueToSourceString(exec, m_constantRegisters[i].jsValue()).utf8().data());
+            ++i;
+            ++registerIndex;
+        } while (i < m_constantRegisters.size());
+    }
+
+    if (m_rareData && !m_rareData->m_regexps.isEmpty()) {
+        printf("\nm_regexps:\n");
+        size_t i = 0;
+        do {
+            printf("  re%u = %s\n", static_cast<unsigned>(i), regexpToSourceString(m_rareData->m_regexps[i].get()).utf8().data());
+            ++i;
+        } while (i < m_rareData->m_regexps.size());
+    }
+
+#if ENABLE(JIT)
+    if (!m_globalResolveInfos.isEmpty() || !m_structureStubInfos.isEmpty())
+        printf("\nStructures:\n");
+
+    if (!m_globalResolveInfos.isEmpty()) {
+        size_t i = 0;
+        do {
+             printGlobalResolveInfo(m_globalResolveInfos[i], instructionOffsetForNth(exec, m_instructions, i + 1, isGlobalResolve));
+             ++i;
+        } while (i < m_globalResolveInfos.size());
+    }
+    if (!m_structureStubInfos.isEmpty()) {
+        size_t i = 0;
+        do {
+            printStructureStubInfo(m_structureStubInfos[i], instructionOffsetForNth(exec, m_instructions, i + 1, isPropertyAccess));
+             ++i;
+        } while (i < m_structureStubInfos.size());
+    }
+#else
+    if (!m_globalResolveInstructions.isEmpty() || !m_propertyAccessInstructions.isEmpty())
+        printf("\nStructures:\n");
+
+    if (!m_globalResolveInstructions.isEmpty()) {
+        size_t i = 0;
+        do {
+             printStructures(&m_instructions[m_globalResolveInstructions[i]]);
+             ++i;
+        } while (i < m_globalResolveInstructions.size());
+    }
+    if (!m_propertyAccessInstructions.isEmpty()) {
+        size_t i = 0;
+        do {
+            printStructures(&m_instructions[m_propertyAccessInstructions[i]]);
+             ++i;
+        } while (i < m_propertyAccessInstructions.size());
+    }
+#endif
+
+    if (m_rareData && !m_rareData->m_exceptionHandlers.isEmpty()) {
+        printf("\nException Handlers:\n");
+        unsigned i = 0;
+        do {
+            printf("\t %d: { start: [%4d] end: [%4d] target: [%4d] }\n", i + 1, m_rareData->m_exceptionHandlers[i].start, m_rareData->m_exceptionHandlers[i].end, m_rareData->m_exceptionHandlers[i].target);
+            ++i;
+        } while (i < m_rareData->m_exceptionHandlers.size());
+    }
+    
+    if (m_rareData && !m_rareData->m_immediateSwitchJumpTables.isEmpty()) {
+        printf("Immediate Switch Jump Tables:\n");
+        unsigned i = 0;
+        do {
+            printf("  %1d = {\n", i);
+            int entry = 0;
+            Vector<int32_t>::const_iterator end = m_rareData->m_immediateSwitchJumpTables[i].branchOffsets.end();
+            for (Vector<int32_t>::const_iterator iter = m_rareData->m_immediateSwitchJumpTables[i].branchOffsets.begin(); iter != end; ++iter, ++entry) {
+                if (!*iter)
+                    continue;
+                printf("\t\t%4d => %04d\n", entry + m_rareData->m_immediateSwitchJumpTables[i].min, *iter);
+            }
+            printf("      }\n");
+            ++i;
+        } while (i < m_rareData->m_immediateSwitchJumpTables.size());
+    }
+    
+    if (m_rareData && !m_rareData->m_characterSwitchJumpTables.isEmpty()) {
+        printf("\nCharacter Switch Jump Tables:\n");
+        unsigned i = 0;
+        do {
+            printf("  %1d = {\n", i);
+            int entry = 0;
+            Vector<int32_t>::const_iterator end = m_rareData->m_characterSwitchJumpTables[i].branchOffsets.end();
+            for (Vector<int32_t>::const_iterator iter = m_rareData->m_characterSwitchJumpTables[i].branchOffsets.begin(); iter != end; ++iter, ++entry) {
+                if (!*iter)
+                    continue;
+                ASSERT(!((i + m_rareData->m_characterSwitchJumpTables[i].min) & ~0xFFFF));
+                UChar ch = static_cast<UChar>(entry + m_rareData->m_characterSwitchJumpTables[i].min);
+                printf("\t\t\"%s\" => %04d\n", UString(&ch, 1).utf8().data(), *iter);
+        }
+            printf("      }\n");
+            ++i;
+        } while (i < m_rareData->m_characterSwitchJumpTables.size());
+    }
+    
+    if (m_rareData && !m_rareData->m_stringSwitchJumpTables.isEmpty()) {
+        printf("\nString Switch Jump Tables:\n");
+        unsigned i = 0;
+        do {
+            printf("  %1d = {\n", i);
+            StringJumpTable::StringOffsetTable::const_iterator end = m_rareData->m_stringSwitchJumpTables[i].offsetTable.end();
+            for (StringJumpTable::StringOffsetTable::const_iterator iter = m_rareData->m_stringSwitchJumpTables[i].offsetTable.begin(); iter != end; ++iter)
+                printf("\t\t\"%s\" => %04d\n", UString(iter->first).utf8().data(), iter->second.branchOffset);
+            printf("      }\n");
+            ++i;
+        } while (i < m_rareData->m_stringSwitchJumpTables.size());
+    }
+
+    printf("\n");
+}
+
+void CodeBlock::dump(ExecState* exec, const Vector<Instruction>::const_iterator& begin, Vector<Instruction>::const_iterator& it) const
+{
+    int location = it - begin;
+    switch (exec->interpreter()->getOpcodeID(it->u.opcode)) {
+        case op_enter: {
+            printf("[%4d] enter\n", location);
+            break;
+        }
+        case op_create_activation: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] create_activation %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_create_arguments: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] create_arguments\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_init_lazy_reg: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] init_lazy_reg\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_get_callee: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] op_get_callee %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_create_this: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] create_this %s %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data());
+            break;
+        }
+        case op_convert_this: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] convert_this %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_convert_this_strict: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] convert_this_strict %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_new_object: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] new_object\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_new_array: {
+            int dst = (++it)->u.operand;
+            int argv = (++it)->u.operand;
+            int argc = (++it)->u.operand;
+            printf("[%4d] new_array\t %s, %s, %d\n", location, registerName(exec, dst).data(), registerName(exec, argv).data(), argc);
+            break;
+        }
+        case op_new_regexp: {
+            int r0 = (++it)->u.operand;
+            int re0 = (++it)->u.operand;
+            printf("[%4d] new_regexp\t %s, %s\n", location, registerName(exec, r0).data(), regexpName(re0, regexp(re0)).data());
+            break;
+        }
+        case op_mov: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] mov\t\t %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data());
+            break;
+        }
+        case op_not: {
+            printUnaryOp(exec, location, it, "not");
+            break;
+        }
+        case op_eq: {
+            printBinaryOp(exec, location, it, "eq");
+            break;
+        }
+        case op_eq_null: {
+            printUnaryOp(exec, location, it, "eq_null");
+            break;
+        }
+        case op_neq: {
+            printBinaryOp(exec, location, it, "neq");
+            break;
+        }
+        case op_neq_null: {
+            printUnaryOp(exec, location, it, "neq_null");
+            break;
+        }
+        case op_stricteq: {
+            printBinaryOp(exec, location, it, "stricteq");
+            break;
+        }
+        case op_nstricteq: {
+            printBinaryOp(exec, location, it, "nstricteq");
+            break;
+        }
+        case op_less: {
+            printBinaryOp(exec, location, it, "less");
+            break;
+        }
+        case op_lesseq: {
+            printBinaryOp(exec, location, it, "lesseq");
+            break;
+        }
+        case op_pre_inc: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] pre_inc\t\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_pre_dec: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] pre_dec\t\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_post_inc: {
+            printUnaryOp(exec, location, it, "post_inc");
+            break;
+        }
+        case op_post_dec: {
+            printUnaryOp(exec, location, it, "post_dec");
+            break;
+        }
+        case op_to_jsnumber: {
+            printUnaryOp(exec, location, it, "to_jsnumber");
+            break;
+        }
+        case op_negate: {
+            printUnaryOp(exec, location, it, "negate");
+            break;
+        }
+        case op_add: {
+            printBinaryOp(exec, location, it, "add");
+            ++it;
+            break;
+        }
+        case op_mul: {
+            printBinaryOp(exec, location, it, "mul");
+            ++it;
+            break;
+        }
+        case op_div: {
+            printBinaryOp(exec, location, it, "div");
+            ++it;
+            break;
+        }
+        case op_mod: {
+            printBinaryOp(exec, location, it, "mod");
+            break;
+        }
+        case op_sub: {
+            printBinaryOp(exec, location, it, "sub");
+            ++it;
+            break;
+        }
+        case op_lshift: {
+            printBinaryOp(exec, location, it, "lshift");
+            break;            
+        }
+        case op_rshift: {
+            printBinaryOp(exec, location, it, "rshift");
+            break;
+        }
+        case op_urshift: {
+            printBinaryOp(exec, location, it, "urshift");
+            break;
+        }
+        case op_bitand: {
+            printBinaryOp(exec, location, it, "bitand");
+            ++it;
+            break;
+        }
+        case op_bitxor: {
+            printBinaryOp(exec, location, it, "bitxor");
+            ++it;
+            break;
+        }
+        case op_bitor: {
+            printBinaryOp(exec, location, it, "bitor");
+            ++it;
+            break;
+        }
+        case op_bitnot: {
+            printUnaryOp(exec, location, it, "bitnot");
+            break;
+        }
+        case op_check_has_instance: {
+            int base = (++it)->u.operand;
+            printf("[%4d] check_has_instance\t\t %s\n", location, registerName(exec, base).data());
+            break;
+        }
+        case op_instanceof: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int r2 = (++it)->u.operand;
+            int r3 = (++it)->u.operand;
+            printf("[%4d] instanceof\t\t %s, %s, %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), registerName(exec, r2).data(), registerName(exec, r3).data());
+            break;
+        }
+        case op_typeof: {
+            printUnaryOp(exec, location, it, "typeof");
+            break;
+        }
+        case op_is_undefined: {
+            printUnaryOp(exec, location, it, "is_undefined");
+            break;
+        }
+        case op_is_boolean: {
+            printUnaryOp(exec, location, it, "is_boolean");
+            break;
+        }
+        case op_is_number: {
+            printUnaryOp(exec, location, it, "is_number");
+            break;
+        }
+        case op_is_string: {
+            printUnaryOp(exec, location, it, "is_string");
+            break;
+        }
+        case op_is_object: {
+            printUnaryOp(exec, location, it, "is_object");
+            break;
+        }
+        case op_is_function: {
+            printUnaryOp(exec, location, it, "is_function");
+            break;
+        }
+        case op_in: {
+            printBinaryOp(exec, location, it, "in");
+            break;
+        }
+        case op_resolve: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            printf("[%4d] resolve\t\t %s, %s\n", location, registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data());
+            break;
+        }
+        case op_resolve_skip: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            int skipLevels = (++it)->u.operand;
+            printf("[%4d] resolve_skip\t %s, %s, %d\n", location, registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data(), skipLevels);
+            break;
+        }
+        case op_resolve_global: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            printf("[%4d] resolve_global\t %s, %s\n", location, registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data());
+            it += 2;
+            break;
+        }
+        case op_resolve_global_dynamic: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            JSValue scope = JSValue((++it)->u.jsCell);
+            ++it;
+            int depth = (++it)->u.operand;
+            printf("[%4d] resolve_global_dynamic\t %s, %s, %s, %d\n", location, registerName(exec, r0).data(), valueToSourceString(exec, scope).utf8().data(), idName(id0, m_identifiers[id0]).data(), depth);
+            break;
+        }
+        case op_get_scoped_var: {
+            int r0 = (++it)->u.operand;
+            int index = (++it)->u.operand;
+            int skipLevels = (++it)->u.operand;
+            printf("[%4d] get_scoped_var\t %s, %d, %d\n", location, registerName(exec, r0).data(), index, skipLevels);
+            break;
+        }
+        case op_put_scoped_var: {
+            int index = (++it)->u.operand;
+            int skipLevels = (++it)->u.operand;
+            int r0 = (++it)->u.operand;
+            printf("[%4d] put_scoped_var\t %d, %d, %s\n", location, index, skipLevels, registerName(exec, r0).data());
+            break;
+        }
+        case op_get_global_var: {
+            int r0 = (++it)->u.operand;
+            int index = (++it)->u.operand;
+            printf("[%4d] get_global_var\t %s, %d\n", location, registerName(exec, r0).data(), index);
+            break;
+        }
+        case op_put_global_var: {
+            int index = (++it)->u.operand;
+            int r0 = (++it)->u.operand;
+            printf("[%4d] put_global_var\t %d, %s\n", location, index, registerName(exec, r0).data());
+            break;
+        }
+        case op_resolve_base: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            int isStrict = (++it)->u.operand;
+            printf("[%4d] resolve_base%s\t %s, %s\n", location, isStrict ? "_strict" : "", registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data());
+            break;
+        }
+        case op_ensure_property_exists: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            printf("[%4d] ensure_property_exists\t %s, %s\n", location, registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data());
+            break;
+        }
+        case op_resolve_with_base: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            printf("[%4d] resolve_with_base %s, %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), idName(id0, m_identifiers[id0]).data());
+            break;
+        }
+        case op_get_by_id: {
+            printGetByIdOp(exec, location, it, "get_by_id");
+            break;
+        }
+        case op_get_by_id_self: {
+            printGetByIdOp(exec, location, it, "get_by_id_self");
+            break;
+        }
+        case op_get_by_id_self_list: {
+            printGetByIdOp(exec, location, it, "get_by_id_self_list");
+            break;
+        }
+        case op_get_by_id_proto: {
+            printGetByIdOp(exec, location, it, "get_by_id_proto");
+            break;
+        }
+        case op_get_by_id_proto_list: {
+            printGetByIdOp(exec, location, it, "op_get_by_id_proto_list");
+            break;
+        }
+        case op_get_by_id_chain: {
+            printGetByIdOp(exec, location, it, "get_by_id_chain");
+            break;
+        }
+        case op_get_by_id_getter_self: {
+            printGetByIdOp(exec, location, it, "get_by_id_getter_self");
+            break;
+        }
+        case op_get_by_id_getter_self_list: {
+            printGetByIdOp(exec, location, it, "get_by_id_getter_self_list");
+            break;
+        }
+        case op_get_by_id_getter_proto: {
+            printGetByIdOp(exec, location, it, "get_by_id_getter_proto");
+            break;
+        }
+        case op_get_by_id_getter_proto_list: {
+            printGetByIdOp(exec, location, it, "get_by_id_getter_proto_list");
+            break;
+        }
+        case op_get_by_id_getter_chain: {
+            printGetByIdOp(exec, location, it, "get_by_id_getter_chain");
+            break;
+        }
+        case op_get_by_id_custom_self: {
+            printGetByIdOp(exec, location, it, "get_by_id_custom_self");
+            break;
+        }
+        case op_get_by_id_custom_self_list: {
+            printGetByIdOp(exec, location, it, "get_by_id_custom_self_list");
+            break;
+        }
+        case op_get_by_id_custom_proto: {
+            printGetByIdOp(exec, location, it, "get_by_id_custom_proto");
+            break;
+        }
+        case op_get_by_id_custom_proto_list: {
+            printGetByIdOp(exec, location, it, "get_by_id_custom_proto_list");
+            break;
+        }
+        case op_get_by_id_custom_chain: {
+            printGetByIdOp(exec, location, it, "get_by_id_custom_chain");
+            break;
+        }
+        case op_get_by_id_generic: {
+            printGetByIdOp(exec, location, it, "get_by_id_generic");
+            break;
+        }
+        case op_get_array_length: {
+            printGetByIdOp(exec, location, it, "get_array_length");
+            break;
+        }
+        case op_get_string_length: {
+            printGetByIdOp(exec, location, it, "get_string_length");
+            break;
+        }
+        case op_get_arguments_length: {
+            printUnaryOp(exec, location, it, "get_arguments_length");
+            it++;
+            break;
+        }
+        case op_put_by_id: {
+            printPutByIdOp(exec, location, it, "put_by_id");
+            break;
+        }
+        case op_put_by_id_replace: {
+            printPutByIdOp(exec, location, it, "put_by_id_replace");
+            break;
+        }
+        case op_put_by_id_transition: {
+            printPutByIdOp(exec, location, it, "put_by_id_transition");
+            break;
+        }
+        case op_put_by_id_generic: {
+            printPutByIdOp(exec, location, it, "put_by_id_generic");
+            break;
+        }
+        case op_put_getter: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] put_getter\t %s, %s, %s\n", location, registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data(), registerName(exec, r1).data());
+            break;
+        }
+        case op_put_setter: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] put_setter\t %s, %s, %s\n", location, registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data(), registerName(exec, r1).data());
+            break;
+        }
+        case op_method_check: {
+            printf("[%4d] method_check\n", location);
+            break;
+        }
+        case op_del_by_id: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            printf("[%4d] del_by_id\t %s, %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), idName(id0, m_identifiers[id0]).data());
+            break;
+        }
+        case op_get_by_val: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int r2 = (++it)->u.operand;
+            printf("[%4d] get_by_val\t %s, %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), registerName(exec, r2).data());
+            break;
+        }
+        case op_get_argument_by_val: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int r2 = (++it)->u.operand;
+            printf("[%4d] get_argument_by_val\t %s, %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), registerName(exec, r2).data());
+            break;
+        }
+        case op_get_by_pname: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int r2 = (++it)->u.operand;
+            int r3 = (++it)->u.operand;
+            int r4 = (++it)->u.operand;
+            int r5 = (++it)->u.operand;
+            printf("[%4d] get_by_pname\t %s, %s, %s, %s, %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), registerName(exec, r2).data(), registerName(exec, r3).data(), registerName(exec, r4).data(), registerName(exec, r5).data());
+            break;
+        }
+        case op_put_by_val: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int r2 = (++it)->u.operand;
+            printf("[%4d] put_by_val\t %s, %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), registerName(exec, r2).data());
+            break;
+        }
+        case op_del_by_val: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int r2 = (++it)->u.operand;
+            printf("[%4d] del_by_val\t %s, %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), registerName(exec, r2).data());
+            break;
+        }
+        case op_put_by_index: {
+            int r0 = (++it)->u.operand;
+            unsigned n0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] put_by_index\t %s, %u, %s\n", location, registerName(exec, r0).data(), n0, registerName(exec, r1).data());
+            break;
+        }
+        case op_jmp: {
+            int offset = (++it)->u.operand;
+            printf("[%4d] jmp\t\t %d(->%d)\n", location, offset, location + offset);
+            break;
+        }
+        case op_loop: {
+            int offset = (++it)->u.operand;
+            printf("[%4d] loop\t\t %d(->%d)\n", location, offset, location + offset);
+            break;
+        }
+        case op_jtrue: {
+            printConditionalJump(exec, begin, it, location, "jtrue");
+            break;
+        }
+        case op_loop_if_true: {
+            printConditionalJump(exec, begin, it, location, "loop_if_true");
+            break;
+        }
+        case op_loop_if_false: {
+            printConditionalJump(exec, begin, it, location, "loop_if_false");
+            break;
+        }
+        case op_jfalse: {
+            printConditionalJump(exec, begin, it, location, "jfalse");
+            break;
+        }
+        case op_jeq_null: {
+            printConditionalJump(exec, begin, it, location, "jeq_null");
+            break;
+        }
+        case op_jneq_null: {
+            printConditionalJump(exec, begin, it, location, "jneq_null");
+            break;
+        }
+        case op_jneq_ptr: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jneq_ptr\t\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_jnless: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jnless\t\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_jnlesseq: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jnlesseq\t\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_loop_if_less: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] loop_if_less\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_jless: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jless\t\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_jlesseq: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jlesseq\t\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_loop_if_lesseq: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] loop_if_lesseq\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_switch_imm: {
+            int tableIndex = (++it)->u.operand;
+            int defaultTarget = (++it)->u.operand;
+            int scrutineeRegister = (++it)->u.operand;
+            printf("[%4d] switch_imm\t %d, %d(->%d), %s\n", location, tableIndex, defaultTarget, location + defaultTarget, registerName(exec, scrutineeRegister).data());
+            break;
+        }
+        case op_switch_char: {
+            int tableIndex = (++it)->u.operand;
+            int defaultTarget = (++it)->u.operand;
+            int scrutineeRegister = (++it)->u.operand;
+            printf("[%4d] switch_char\t %d, %d(->%d), %s\n", location, tableIndex, defaultTarget, location + defaultTarget, registerName(exec, scrutineeRegister).data());
+            break;
+        }
+        case op_switch_string: {
+            int tableIndex = (++it)->u.operand;
+            int defaultTarget = (++it)->u.operand;
+            int scrutineeRegister = (++it)->u.operand;
+            printf("[%4d] switch_string\t %d, %d(->%d), %s\n", location, tableIndex, defaultTarget, location + defaultTarget, registerName(exec, scrutineeRegister).data());
+            break;
+        }
+        case op_new_func: {
+            int r0 = (++it)->u.operand;
+            int f0 = (++it)->u.operand;
+            int shouldCheck = (++it)->u.operand;
+            printf("[%4d] new_func\t\t %s, f%d, %s\n", location, registerName(exec, r0).data(), f0, shouldCheck ? "<Checked>" : "<Unchecked>");
+            break;
+        }
+        case op_new_func_exp: {
+            int r0 = (++it)->u.operand;
+            int f0 = (++it)->u.operand;
+            printf("[%4d] new_func_exp\t %s, f%d\n", location, registerName(exec, r0).data(), f0);
+            break;
+        }
+        case op_call: {
+            int func = (++it)->u.operand;
+            int argCount = (++it)->u.operand;
+            int registerOffset = (++it)->u.operand;
+            printf("[%4d] call\t\t %s, %d, %d\n", location, registerName(exec, func).data(), argCount, registerOffset);
+            break;
+        }
+        case op_call_eval: {
+            int func = (++it)->u.operand;
+            int argCount = (++it)->u.operand;
+            int registerOffset = (++it)->u.operand;
+            printf("[%4d] call_eval\t %s, %d, %d\n", location, registerName(exec, func).data(), argCount, registerOffset);
+            break;
+        }
+        case op_call_varargs: {
+            int func = (++it)->u.operand;
+            int argCount = (++it)->u.operand;
+            int registerOffset = (++it)->u.operand;
+            printf("[%4d] call_varargs\t %s, %s, %d\n", location, registerName(exec, func).data(), registerName(exec, argCount).data(), registerOffset);
+            break;
+        }
+        case op_load_varargs: {
+            printUnaryOp(exec, location, it, "load_varargs");
+            break;
+        }
+        case op_tear_off_activation: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] tear_off_activation\t %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data());
+            break;
+        }
+        case op_tear_off_arguments: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] tear_off_arguments\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_ret: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] ret\t\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_call_put_result: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] op_call_put_result\t\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_ret_object_or_this: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] constructor_ret\t\t %s %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data());
+            break;
+        }
+        case op_construct: {
+            int func = (++it)->u.operand;
+            int argCount = (++it)->u.operand;
+            int registerOffset = (++it)->u.operand;
+            printf("[%4d] construct\t %s, %d, %d\n", location, registerName(exec, func).data(), argCount, registerOffset);
+            break;
+        }
+        case op_strcat: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int count = (++it)->u.operand;
+            printf("[%4d] strcat\t\t %s, %s, %d\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), count);
+            break;
+        }
+        case op_to_primitive: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] to_primitive\t %s, %s\n", location, registerName(exec, r0).data(), registerName(exec, r1).data());
+            break;
+        }
+        case op_get_pnames: {
+            int r0 = it[1].u.operand;
+            int r1 = it[2].u.operand;
+            int r2 = it[3].u.operand;
+            int r3 = it[4].u.operand;
+            int offset = it[5].u.operand;
+            printf("[%4d] get_pnames\t %s, %s, %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), registerName(exec, r2).data(), registerName(exec, r3).data(), offset, location + offset);
+            it += OPCODE_LENGTH(op_get_pnames) - 1;
+            break;
+        }
+        case op_next_pname: {
+            int dest = it[1].u.operand;
+            int base = it[2].u.operand;
+            int i = it[3].u.operand;
+            int size = it[4].u.operand;
+            int iter = it[5].u.operand;
+            int offset = it[6].u.operand;
+            printf("[%4d] next_pname\t %s, %s, %s, %s, %s, %d(->%d)\n", location, registerName(exec, dest).data(), registerName(exec, base).data(), registerName(exec, i).data(), registerName(exec, size).data(), registerName(exec, iter).data(), offset, location + offset);
+            it += OPCODE_LENGTH(op_next_pname) - 1;
+            break;
+        }
+        case op_push_scope: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] push_scope\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_pop_scope: {
+            printf("[%4d] pop_scope\n", location);
+            break;
+        }
+        case op_push_new_scope: {
+            int r0 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            printf("[%4d] push_new_scope \t%s, %s, %s\n", location, registerName(exec, r0).data(), idName(id0, m_identifiers[id0]).data(), registerName(exec, r1).data());
+            break;
+        }
+        case op_jmp_scopes: {
+            int scopeDelta = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jmp_scopes\t^%d, %d(->%d)\n", location, scopeDelta, offset, location + offset);
+            break;
+        }
+        case op_catch: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] catch\t\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_throw: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] throw\t\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+        case op_throw_reference_error: {
+            int k0 = (++it)->u.operand;
+            printf("[%4d] throw_reference_error\t %s\n", location, constantName(exec, k0, getConstant(k0)).data());
+            break;
+        }
+        case op_throw_syntax_error: {
+            int k0 = (++it)->u.operand;
+            printf("[%4d] throw_syntax_error\t %s\n", location, constantName(exec, k0, getConstant(k0)).data());
+            break;
+        }
+        case op_jsr: {
+            int retAddrDst = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jsr\t\t %s, %d(->%d)\n", location, registerName(exec, retAddrDst).data(), offset, location + offset);
+            break;
+        }
+        case op_sret: {
+            int retAddrSrc = (++it)->u.operand;
+            printf("[%4d] sret\t\t %s\n", location, registerName(exec, retAddrSrc).data());
+            break;
+        }
+        case op_debug: {
+            int debugHookID = (++it)->u.operand;
+            int firstLine = (++it)->u.operand;
+            int lastLine = (++it)->u.operand;
+            printf("[%4d] debug\t\t %s, %d, %d\n", location, debugHookName(debugHookID), firstLine, lastLine);
+            break;
+        }
+        case op_profile_will_call: {
+            int function = (++it)->u.operand;
+            printf("[%4d] profile_will_call %s\n", location, registerName(exec, function).data());
+            break;
+        }
+        case op_profile_did_call: {
+            int function = (++it)->u.operand;
+            printf("[%4d] profile_did_call\t %s\n", location, registerName(exec, function).data());
+            break;
+        }
+        case op_end: {
+            int r0 = (++it)->u.operand;
+            printf("[%4d] end\t\t %s\n", location, registerName(exec, r0).data());
+            break;
+        }
+    }
+}
+
+#endif // !defined(NDEBUG) || ENABLE(OPCODE_SAMPLING)
+
+#if DUMP_CODE_BLOCK_STATISTICS
+static HashSet<CodeBlock*> liveCodeBlockSet;
+#endif
+
+#define FOR_EACH_MEMBER_VECTOR(macro) \
+    macro(instructions) \
+    macro(globalResolveInfos) \
+    macro(structureStubInfos) \
+    macro(callLinkInfos) \
+    macro(linkedCallerList) \
+    macro(identifiers) \
+    macro(functionExpressions) \
+    macro(constantRegisters)
+
+#define FOR_EACH_MEMBER_VECTOR_RARE_DATA(macro) \
+    macro(regexps) \
+    macro(functions) \
+    macro(exceptionHandlers) \
+    macro(immediateSwitchJumpTables) \
+    macro(characterSwitchJumpTables) \
+    macro(stringSwitchJumpTables) \
+    macro(evalCodeCache) \
+    macro(expressionInfo) \
+    macro(lineInfo) \
+    macro(callReturnIndexVector)
+
+template<typename T>
+static size_t sizeInBytes(const Vector<T>& vector)
+{
+    return vector.capacity() * sizeof(T);
+}
+
+void CodeBlock::dumpStatistics()
+{
+#if DUMP_CODE_BLOCK_STATISTICS
+    #define DEFINE_VARS(name) size_t name##IsNotEmpty = 0; size_t name##TotalSize = 0;
+        FOR_EACH_MEMBER_VECTOR(DEFINE_VARS)
+        FOR_EACH_MEMBER_VECTOR_RARE_DATA(DEFINE_VARS)
+    #undef DEFINE_VARS
+
+    // Non-vector data members
+    size_t evalCodeCacheIsNotEmpty = 0;
+
+    size_t symbolTableIsNotEmpty = 0;
+    size_t symbolTableTotalSize = 0;
+
+    size_t hasRareData = 0;
+
+    size_t isFunctionCode = 0;
+    size_t isGlobalCode = 0;
+    size_t isEvalCode = 0;
+
+    HashSet<CodeBlock*>::const_iterator end = liveCodeBlockSet.end();
+    for (HashSet<CodeBlock*>::const_iterator it = liveCodeBlockSet.begin(); it != end; ++it) {
+        CodeBlock* codeBlock = *it;
+
+        #define GET_STATS(name) if (!codeBlock->m_##name.isEmpty()) { name##IsNotEmpty++; name##TotalSize += sizeInBytes(codeBlock->m_##name); }
+            FOR_EACH_MEMBER_VECTOR(GET_STATS)
+        #undef GET_STATS
+
+        if (!codeBlock->m_symbolTable.isEmpty()) {
+            symbolTableIsNotEmpty++;
+            symbolTableTotalSize += (codeBlock->m_symbolTable.capacity() * (sizeof(SymbolTable::KeyType) + sizeof(SymbolTable::MappedType)));
+        }
+
+        if (codeBlock->m_rareData) {
+            hasRareData++;
+            #define GET_STATS(name) if (!codeBlock->m_rareData->m_##name.isEmpty()) { name##IsNotEmpty++; name##TotalSize += sizeInBytes(codeBlock->m_rareData->m_##name); }
+                FOR_EACH_MEMBER_VECTOR_RARE_DATA(GET_STATS)
+            #undef GET_STATS
+
+            if (!codeBlock->m_rareData->m_evalCodeCache.isEmpty())
+                evalCodeCacheIsNotEmpty++;
+        }
+
+        switch (codeBlock->codeType()) {
+            case FunctionCode:
+                ++isFunctionCode;
+                break;
+            case GlobalCode:
+                ++isGlobalCode;
+                break;
+            case EvalCode:
+                ++isEvalCode;
+                break;
+        }
+    }
+
+    size_t totalSize = 0;
+
+    #define GET_TOTAL_SIZE(name) totalSize += name##TotalSize;
+        FOR_EACH_MEMBER_VECTOR(GET_TOTAL_SIZE)
+        FOR_EACH_MEMBER_VECTOR_RARE_DATA(GET_TOTAL_SIZE)
+    #undef GET_TOTAL_SIZE
+
+    totalSize += symbolTableTotalSize;
+    totalSize += (liveCodeBlockSet.size() * sizeof(CodeBlock));
+
+    printf("Number of live CodeBlocks: %d\n", liveCodeBlockSet.size());
+    printf("Size of a single CodeBlock [sizeof(CodeBlock)]: %zu\n", sizeof(CodeBlock));
+    printf("Size of all CodeBlocks: %zu\n", totalSize);
+    printf("Average size of a CodeBlock: %zu\n", totalSize / liveCodeBlockSet.size());
+
+    printf("Number of FunctionCode CodeBlocks: %zu (%.3f%%)\n", isFunctionCode, static_cast<double>(isFunctionCode) * 100.0 / liveCodeBlockSet.size());
+    printf("Number of GlobalCode CodeBlocks: %zu (%.3f%%)\n", isGlobalCode, static_cast<double>(isGlobalCode) * 100.0 / liveCodeBlockSet.size());
+    printf("Number of EvalCode CodeBlocks: %zu (%.3f%%)\n", isEvalCode, static_cast<double>(isEvalCode) * 100.0 / liveCodeBlockSet.size());
+
+    printf("Number of CodeBlocks with rare data: %zu (%.3f%%)\n", hasRareData, static_cast<double>(hasRareData) * 100.0 / liveCodeBlockSet.size());
+
+    #define PRINT_STATS(name) printf("Number of CodeBlocks with " #name ": %zu\n", name##IsNotEmpty); printf("Size of all " #name ": %zu\n", name##TotalSize); 
+        FOR_EACH_MEMBER_VECTOR(PRINT_STATS)
+        FOR_EACH_MEMBER_VECTOR_RARE_DATA(PRINT_STATS)
+    #undef PRINT_STATS
+
+    printf("Number of CodeBlocks with evalCodeCache: %zu\n", evalCodeCacheIsNotEmpty);
+    printf("Number of CodeBlocks with symbolTable: %zu\n", symbolTableIsNotEmpty);
+
+    printf("Size of all symbolTables: %zu\n", symbolTableTotalSize);
+
+#else
+    printf("Dumping CodeBlock statistics is not enabled.\n");
+#endif
+}
+
+CodeBlock::CodeBlock(ScriptExecutable* ownerExecutable, CodeType codeType, JSGlobalObject *globalObject, PassRefPtr<SourceProvider> sourceProvider, unsigned sourceOffset, SymbolTable* symTab, bool isConstructor)
+    : m_globalObject(globalObject)
+    , m_numCalleeRegisters(0)
+    , m_numVars(0)
+    , m_numParameters(0)
+    , m_isConstructor(isConstructor)
+    , m_ownerExecutable(ownerExecutable)
+    , m_globalData(0)
+#ifndef NDEBUG
+    , m_instructionCount(0)
+#endif
+    , m_argumentsRegister(-1)
+    , m_needsFullScopeChain(ownerExecutable->needsActivation())
+    , m_usesEval(ownerExecutable->usesEval())
+    , m_isNumericCompareFunction(false)
+    , m_isStrictMode(ownerExecutable->isStrictMode())
+    , m_codeType(codeType)
+    , m_source(sourceProvider)
+    , m_sourceOffset(sourceOffset)
+    , m_symbolTable(symTab)
+{
+    ASSERT(m_source);
+
+#if DUMP_CODE_BLOCK_STATISTICS
+    liveCodeBlockSet.add(this);
+#endif
+}
+
+CodeBlock::~CodeBlock()
+{
+#if ENABLE(INTERPRETER)
+    for (size_t size = m_globalResolveInstructions.size(), i = 0; i < size; ++i)
+        derefStructures(&m_instructions[m_globalResolveInstructions[i]]);
+
+    for (size_t size = m_propertyAccessInstructions.size(), i = 0; i < size; ++i)
+        derefStructures(&m_instructions[m_propertyAccessInstructions[i]]);
+#endif
+#if ENABLE(JIT)
+    for (size_t size = m_globalResolveInfos.size(), i = 0; i < size; ++i) {
+        if (m_globalResolveInfos[i].structure)
+            m_globalResolveInfos[i].structure->deref();
+    }
+
+    for (size_t size = m_structureStubInfos.size(), i = 0; i < size; ++i)
+        m_structureStubInfos[i].deref();
+
+    for (size_t size = m_callLinkInfos.size(), i = 0; i < size; ++i) {
+        CallLinkInfo* callLinkInfo = &m_callLinkInfos[i];
+        if (callLinkInfo->isLinked())
+            callLinkInfo->callee->removeCaller(callLinkInfo);
+    }
+
+    for (size_t size = m_methodCallLinkInfos.size(), i = 0; i < size; ++i) {
+        if (Structure* structure = m_methodCallLinkInfos[i].cachedStructure) {
+            structure->deref();
+            // Both members must be filled at the same time
+            ASSERT(!!m_methodCallLinkInfos[i].cachedPrototypeStructure);
+            m_methodCallLinkInfos[i].cachedPrototypeStructure->deref();
+        }
+    }
+
+#if ENABLE(JIT_OPTIMIZE_CALL)
+    unlinkCallers();
+#endif
+
+#endif // ENABLE(JIT)
+
+#if DUMP_CODE_BLOCK_STATISTICS
+    liveCodeBlockSet.remove(this);
+#endif
+}
+
+#if ENABLE(JIT_OPTIMIZE_CALL)
+void CodeBlock::unlinkCallers()
+{
+    size_t size = m_linkedCallerList.size();
+    for (size_t i = 0; i < size; ++i) {
+        CallLinkInfo* currentCaller = m_linkedCallerList[i];
+        JIT::unlinkCallOrConstruct(currentCaller);
+        currentCaller->setUnlinked();
+    }
+    m_linkedCallerList.clear();
+}
+#endif
+
+void CodeBlock::derefStructures(Instruction* vPC) const
+{
+    Interpreter* interpreter = m_globalData->interpreter;
+
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_self) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_getter_self) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_custom_self)) {
+        vPC[4].u.structure->deref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_proto) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_getter_proto) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_custom_proto)) {
+        vPC[4].u.structure->deref();
+        vPC[5].u.structure->deref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_chain) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_getter_chain) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_custom_chain)) {
+        vPC[4].u.structure->deref();
+        vPC[5].u.structureChain->deref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_transition)) {
+        vPC[4].u.structure->deref();
+        vPC[5].u.structure->deref();
+        vPC[6].u.structureChain->deref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_replace)) {
+        vPC[4].u.structure->deref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_resolve_global) || vPC[0].u.opcode == interpreter->getOpcode(op_resolve_global_dynamic)) {
+        if (vPC[3].u.structure)
+            vPC[3].u.structure->deref();
+        return;
+    }
+    if ((vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_proto_list))
+        || (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_self_list))
+        || (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_getter_proto_list))
+        || (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_getter_self_list))
+        || (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_custom_proto_list))
+        || (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_custom_self_list))) {
+        PolymorphicAccessStructureList* polymorphicStructures = vPC[4].u.polymorphicStructures;
+        polymorphicStructures->derefStructures(vPC[5].u.operand);
+        delete polymorphicStructures;
+        return;
+    }
+
+    // These instructions don't ref their Structures.
+    ASSERT(vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id) || vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_generic) || vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_generic) || vPC[0].u.opcode == interpreter->getOpcode(op_get_array_length) || vPC[0].u.opcode == interpreter->getOpcode(op_get_string_length));
+}
+
+void CodeBlock::refStructures(Instruction* vPC) const
+{
+    Interpreter* interpreter = m_globalData->interpreter;
+
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_self) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_getter_self) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_custom_self)) {
+        vPC[4].u.structure->ref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_proto) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_getter_proto) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_custom_proto)) {
+        vPC[4].u.structure->ref();
+        vPC[5].u.structure->ref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_chain) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_getter_chain) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_custom_chain)) {
+        vPC[4].u.structure->ref();
+        vPC[5].u.structureChain->ref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_transition)) {
+        vPC[4].u.structure->ref();
+        vPC[5].u.structure->ref();
+        vPC[6].u.structureChain->ref();
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_replace)) {
+        vPC[4].u.structure->ref();
+        return;
+    }
+    
+    // These instructions don't ref their Structures.
+    ASSERT(vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id) || vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id) || vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id_generic) || vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_generic));
+}
+
+void CodeBlock::markAggregate(MarkStack& markStack)
+{
+    for (size_t i = 0; i < m_constantRegisters.size(); ++i)
+        markStack.append(m_constantRegisters[i].jsValue());
+    for (size_t i = 0; i < m_functionExprs.size(); ++i)
+        m_functionExprs[i]->markAggregate(markStack);
+    for (size_t i = 0; i < m_functionDecls.size(); ++i)
+        m_functionDecls[i]->markAggregate(markStack);
+    markStack.append(m_globalObject);
+}
+
+HandlerInfo* CodeBlock::handlerForBytecodeOffset(unsigned bytecodeOffset)
+{
+    ASSERT(bytecodeOffset < m_instructionCount);
+
+    if (!m_rareData)
+        return 0;
+    
+    Vector<HandlerInfo>& exceptionHandlers = m_rareData->m_exceptionHandlers;
+    for (size_t i = 0; i < exceptionHandlers.size(); ++i) {
+        // Handlers are ordered innermost first, so the first handler we encounter
+        // that contains the source address is the correct handler to use.
+        if (exceptionHandlers[i].start <= bytecodeOffset && exceptionHandlers[i].end >= bytecodeOffset)
+            return &exceptionHandlers[i];
+    }
+
+    return 0;
+}
+
+int CodeBlock::lineNumberForBytecodeOffset(unsigned bytecodeOffset)
+{
+    ASSERT(bytecodeOffset < m_instructionCount);
+
+    if (!m_rareData)
+        return m_ownerExecutable->source().firstLine();
+
+    Vector<LineInfo>& lineInfo = m_rareData->m_lineInfo;
+
+    int low = 0;
+    int high = lineInfo.size();
+    while (low < high) {
+        int mid = low + (high - low) / 2;
+        if (lineInfo[mid].instructionOffset <= bytecodeOffset)
+            low = mid + 1;
+        else
+            high = mid;
+    }
+
+    if (!low)
+        return m_ownerExecutable->source().firstLine();
+    return lineInfo[low - 1].lineNumber;
+}
+
+void CodeBlock::expressionRangeForBytecodeOffset(unsigned bytecodeOffset, int& divot, int& startOffset, int& endOffset)
+{
+    ASSERT(bytecodeOffset < m_instructionCount);
+
+    if (!m_rareData) {
+        startOffset = 0;
+        endOffset = 0;
+        divot = 0;
+        return;
+    }
+
+    Vector<ExpressionRangeInfo>& expressionInfo = m_rareData->m_expressionInfo;
+
+    int low = 0;
+    int high = expressionInfo.size();
+    while (low < high) {
+        int mid = low + (high - low) / 2;
+        if (expressionInfo[mid].instructionOffset <= bytecodeOffset)
+            low = mid + 1;
+        else
+            high = mid;
+    }
+
+    ASSERT(low);
+    if (!low) {
+        startOffset = 0;
+        endOffset = 0;
+        divot = 0;
+        return;
+    }
+
+    startOffset = expressionInfo[low - 1].startOffset;
+    endOffset = expressionInfo[low - 1].endOffset;
+    divot = expressionInfo[low - 1].divotPoint + m_sourceOffset;
+    return;
+}
+
+#if ENABLE(INTERPRETER)
+bool CodeBlock::hasGlobalResolveInstructionAtBytecodeOffset(unsigned bytecodeOffset)
+{
+    if (m_globalResolveInstructions.isEmpty())
+        return false;
+
+    int low = 0;
+    int high = m_globalResolveInstructions.size();
+    while (low < high) {
+        int mid = low + (high - low) / 2;
+        if (m_globalResolveInstructions[mid] <= bytecodeOffset)
+            low = mid + 1;
+        else
+            high = mid;
+    }
+
+    if (!low || m_globalResolveInstructions[low - 1] != bytecodeOffset)
+        return false;
+    return true;
+}
+#endif
+#if ENABLE(JIT)
+bool CodeBlock::hasGlobalResolveInfoAtBytecodeOffset(unsigned bytecodeOffset)
+{
+    if (m_globalResolveInfos.isEmpty())
+        return false;
+
+    int low = 0;
+    int high = m_globalResolveInfos.size();
+    while (low < high) {
+        int mid = low + (high - low) / 2;
+        if (m_globalResolveInfos[mid].bytecodeOffset <= bytecodeOffset)
+            low = mid + 1;
+        else
+            high = mid;
+    }
+
+    if (!low || m_globalResolveInfos[low - 1].bytecodeOffset != bytecodeOffset)
+        return false;
+    return true;
+}
+#endif
+
+void CodeBlock::shrinkToFit()
+{
+    m_instructions.shrinkToFit();
+
+#if ENABLE(INTERPRETER)
+    m_propertyAccessInstructions.shrinkToFit();
+    m_globalResolveInstructions.shrinkToFit();
+#endif
+#if ENABLE(JIT)
+    m_structureStubInfos.shrinkToFit();
+    m_globalResolveInfos.shrinkToFit();
+    m_callLinkInfos.shrinkToFit();
+    m_linkedCallerList.shrinkToFit();
+#endif
+
+    m_identifiers.shrinkToFit();
+    m_functionDecls.shrinkToFit();
+    m_functionExprs.shrinkToFit();
+    m_constantRegisters.shrinkToFit();
+
+    if (m_rareData) {
+        m_rareData->m_exceptionHandlers.shrinkToFit();
+        m_rareData->m_regexps.shrinkToFit();
+        m_rareData->m_immediateSwitchJumpTables.shrinkToFit();
+        m_rareData->m_characterSwitchJumpTables.shrinkToFit();
+        m_rareData->m_stringSwitchJumpTables.shrinkToFit();
+        m_rareData->m_expressionInfo.shrinkToFit();
+        m_rareData->m_lineInfo.shrinkToFit();
+    }
+}
+
+void CodeBlock::createActivation(CallFrame* callFrame)
+{
+    ASSERT(codeType() == FunctionCode);
+    ASSERT(needsFullScopeChain());
+    ASSERT(!callFrame->uncheckedR(activationRegister()).jsValue());
+    JSActivation* activation = new (callFrame) JSActivation(callFrame, static_cast<FunctionExecutable*>(ownerExecutable()));
+    callFrame->uncheckedR(activationRegister()) = JSValue(activation);
+    callFrame->setScopeChain(callFrame->scopeChain()->copy()->push(activation));
+}
+
+} // namespace JSC
diff --git a/Source/JavaScriptCore/bytecode/CodeBlock.h b/Source/JavaScriptCore/bytecode/CodeBlock.h
new file mode 100644
index 0000000..7eca72a
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/CodeBlock.h
@@ -0,0 +1,691 @@
+/*
+ * Copyright (C) 2008, 2009, 2010 Apple Inc. All rights reserved.
+ * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef CodeBlock_h
+#define CodeBlock_h
+
+#include "EvalCodeCache.h"
+#include "Instruction.h"
+#include "JITCode.h"
+#include "JSGlobalObject.h"
+#include "JumpTable.h"
+#include "Nodes.h"
+#include "RegExp.h"
+#include "UString.h"
+#include <wtf/FastAllocBase.h>
+#include <wtf/PassOwnPtr.h>
+#include <wtf/RefPtr.h>
+#include <wtf/Vector.h>
+
+#if ENABLE(JIT)
+#include "StructureStubInfo.h"
+#endif
+
+// Register numbers used in bytecode operations have different meaning according to their ranges:
+//      0x80000000-0xFFFFFFFF  Negative indices from the CallFrame pointer are entries in the call frame, see RegisterFile.h.
+//      0x00000000-0x3FFFFFFF  Forwards indices from the CallFrame pointer are local vars and temporaries with the function's callframe.
+//      0x40000000-0x7FFFFFFF  Positive indices from 0x40000000 specify entries in the constant pool on the CodeBlock.
+static const int FirstConstantRegisterIndex = 0x40000000;
+
+namespace JSC {
+
+    enum HasSeenShouldRepatch {
+        hasSeenShouldRepatch
+    };
+
+    class ExecState;
+
+    enum CodeType { GlobalCode, EvalCode, FunctionCode };
+
+    inline int unmodifiedArgumentsRegister(int argumentsRegister) { return argumentsRegister - 1; }
+
+    static ALWAYS_INLINE int missingThisObjectMarker() { return std::numeric_limits<int>::max(); }
+
+    struct HandlerInfo {
+        uint32_t start;
+        uint32_t end;
+        uint32_t target;
+        uint32_t scopeDepth;
+#if ENABLE(JIT)
+        CodeLocationLabel nativeCode;
+#endif
+    };
+
+    struct ExpressionRangeInfo {
+        enum {
+            MaxOffset = (1 << 7) - 1, 
+            MaxDivot = (1 << 25) - 1
+        };
+        uint32_t instructionOffset : 25;
+        uint32_t divotPoint : 25;
+        uint32_t startOffset : 7;
+        uint32_t endOffset : 7;
+    };
+
+    struct LineInfo {
+        uint32_t instructionOffset;
+        int32_t lineNumber;
+    };
+
+#if ENABLE(JIT)
+    struct CallLinkInfo {
+        CallLinkInfo()
+            : callee(0)
+            , position(0)
+            , hasSeenShouldRepatch(0)
+        {
+        }
+
+        CodeLocationNearCall callReturnLocation;
+        CodeLocationDataLabelPtr hotPathBegin;
+        CodeLocationNearCall hotPathOther;
+        CodeBlock* ownerCodeBlock;
+        CodeBlock* callee;
+        unsigned position : 31;
+        unsigned hasSeenShouldRepatch : 1;
+        
+        void setUnlinked() { callee = 0; }
+        bool isLinked() { return callee; }
+
+        bool seenOnce()
+        {
+            return hasSeenShouldRepatch;
+        }
+
+        void setSeen()
+        {
+            hasSeenShouldRepatch = true;
+        }
+    };
+
+    struct MethodCallLinkInfo {
+        MethodCallLinkInfo()
+            : cachedStructure(0)
+            , cachedPrototypeStructure(0)
+        {
+        }
+
+        bool seenOnce()
+        {
+            ASSERT(!cachedStructure);
+            return cachedPrototypeStructure;
+        }
+
+        void setSeen()
+        {
+            ASSERT(!cachedStructure && !cachedPrototypeStructure);
+            // We use the values of cachedStructure & cachedPrototypeStructure to indicate the
+            // current state.
+            //     - In the initial state, both are null.
+            //     - Once this transition has been taken once, cachedStructure is
+            //       null and cachedPrototypeStructure is set to a nun-null value.
+            //     - Once the call is linked both structures are set to non-null values.
+            cachedPrototypeStructure = (Structure*)1;
+        }
+
+        CodeLocationCall callReturnLocation;
+        CodeLocationDataLabelPtr structureLabel;
+        Structure* cachedStructure;
+        Structure* cachedPrototypeStructure;
+    };
+
+    struct GlobalResolveInfo {
+        GlobalResolveInfo(unsigned bytecodeOffset)
+            : structure(0)
+            , offset(0)
+            , bytecodeOffset(bytecodeOffset)
+        {
+        }
+
+        Structure* structure;
+        unsigned offset;
+        unsigned bytecodeOffset;
+    };
+
+    // This structure is used to map from a call return location
+    // (given as an offset in bytes into the JIT code) back to
+    // the bytecode index of the corresponding bytecode operation.
+    // This is then used to look up the corresponding handler.
+    struct CallReturnOffsetToBytecodeOffset {
+        CallReturnOffsetToBytecodeOffset(unsigned callReturnOffset, unsigned bytecodeOffset)
+            : callReturnOffset(callReturnOffset)
+            , bytecodeOffset(bytecodeOffset)
+        {
+        }
+
+        unsigned callReturnOffset;
+        unsigned bytecodeOffset;
+    };
+
+    // valueAtPosition helpers for the binaryChop algorithm below.
+
+    inline void* getStructureStubInfoReturnLocation(StructureStubInfo* structureStubInfo)
+    {
+        return structureStubInfo->callReturnLocation.executableAddress();
+    }
+
+    inline void* getCallLinkInfoReturnLocation(CallLinkInfo* callLinkInfo)
+    {
+        return callLinkInfo->callReturnLocation.executableAddress();
+    }
+
+    inline void* getMethodCallLinkInfoReturnLocation(MethodCallLinkInfo* methodCallLinkInfo)
+    {
+        return methodCallLinkInfo->callReturnLocation.executableAddress();
+    }
+
+    inline unsigned getCallReturnOffset(CallReturnOffsetToBytecodeOffset* pc)
+    {
+        return pc->callReturnOffset;
+    }
+
+    // Binary chop algorithm, calls valueAtPosition on pre-sorted elements in array,
+    // compares result with key (KeyTypes should be comparable with '--', '<', '>').
+    // Optimized for cases where the array contains the key, checked by assertions.
+    template<typename ArrayType, typename KeyType, KeyType(*valueAtPosition)(ArrayType*)>
+    inline ArrayType* binaryChop(ArrayType* array, size_t size, KeyType key)
+    {
+        // The array must contain at least one element (pre-condition, array does conatin key).
+        // If the array only contains one element, no need to do the comparison.
+        while (size > 1) {
+            // Pick an element to check, half way through the array, and read the value.
+            int pos = (size - 1) >> 1;
+            KeyType val = valueAtPosition(&array[pos]);
+            
+            // If the key matches, success!
+            if (val == key)
+                return &array[pos];
+            // The item we are looking for is smaller than the item being check; reduce the value of 'size',
+            // chopping off the right hand half of the array.
+            else if (key < val)
+                size = pos;
+            // Discard all values in the left hand half of the array, up to and including the item at pos.
+            else {
+                size -= (pos + 1);
+                array += (pos + 1);
+            }
+
+            // 'size' should never reach zero.
+            ASSERT(size);
+        }
+        
+        // If we reach this point we've chopped down to one element, no need to check it matches
+        ASSERT(size == 1);
+        ASSERT(key == valueAtPosition(&array[0]));
+        return &array[0];
+    }
+#endif
+
+    class CodeBlock : public FastAllocBase {
+        friend class JIT;
+    protected:
+        CodeBlock(ScriptExecutable* ownerExecutable, CodeType, JSGlobalObject*, PassRefPtr<SourceProvider>, unsigned sourceOffset, SymbolTable* symbolTable, bool isConstructor);
+
+        JSGlobalObject* m_globalObject;
+
+    public:
+        virtual ~CodeBlock();
+
+        void markAggregate(MarkStack&);
+        void refStructures(Instruction* vPC) const;
+        void derefStructures(Instruction* vPC) const;
+#if ENABLE(JIT_OPTIMIZE_CALL)
+        void unlinkCallers();
+#endif
+
+        static void dumpStatistics();
+
+#if !defined(NDEBUG) || ENABLE_OPCODE_SAMPLING
+        void dump(ExecState*) const;
+        void printStructures(const Instruction*) const;
+        void printStructure(const char* name, const Instruction*, int operand) const;
+#endif
+
+        bool isStrictMode() const { return m_isStrictMode; }
+
+        inline bool isKnownNotImmediate(int index)
+        {
+            if (index == m_thisRegister && !m_isStrictMode)
+                return true;
+
+            if (isConstantRegisterIndex(index))
+                return getConstant(index).isCell();
+
+            return false;
+        }
+
+        ALWAYS_INLINE bool isTemporaryRegisterIndex(int index)
+        {
+            return index >= m_numVars;
+        }
+
+        HandlerInfo* handlerForBytecodeOffset(unsigned bytecodeOffset);
+        int lineNumberForBytecodeOffset(unsigned bytecodeOffset);
+        void expressionRangeForBytecodeOffset(unsigned bytecodeOffset, int& divot, int& startOffset, int& endOffset);
+
+#if ENABLE(JIT)
+        void addCaller(CallLinkInfo* caller)
+        {
+            caller->callee = this;
+            caller->position = m_linkedCallerList.size();
+            m_linkedCallerList.append(caller);
+        }
+
+        void removeCaller(CallLinkInfo* caller)
+        {
+            unsigned pos = caller->position;
+            unsigned lastPos = m_linkedCallerList.size() - 1;
+
+            if (pos != lastPos) {
+                m_linkedCallerList[pos] = m_linkedCallerList[lastPos];
+                m_linkedCallerList[pos]->position = pos;
+            }
+            m_linkedCallerList.shrink(lastPos);
+        }
+
+        StructureStubInfo& getStubInfo(ReturnAddressPtr returnAddress)
+        {
+            return *(binaryChop<StructureStubInfo, void*, getStructureStubInfoReturnLocation>(m_structureStubInfos.begin(), m_structureStubInfos.size(), returnAddress.value()));
+        }
+
+        CallLinkInfo& getCallLinkInfo(ReturnAddressPtr returnAddress)
+        {
+            return *(binaryChop<CallLinkInfo, void*, getCallLinkInfoReturnLocation>(m_callLinkInfos.begin(), m_callLinkInfos.size(), returnAddress.value()));
+        }
+
+        MethodCallLinkInfo& getMethodCallLinkInfo(ReturnAddressPtr returnAddress)
+        {
+            return *(binaryChop<MethodCallLinkInfo, void*, getMethodCallLinkInfoReturnLocation>(m_methodCallLinkInfos.begin(), m_methodCallLinkInfos.size(), returnAddress.value()));
+        }
+
+        unsigned bytecodeOffset(ReturnAddressPtr returnAddress)
+        {
+            if (!m_rareData)
+                return 1;
+            Vector<CallReturnOffsetToBytecodeOffset>& callIndices = m_rareData->m_callReturnIndexVector;
+            if (!callIndices.size())
+                return 1;
+            return binaryChop<CallReturnOffsetToBytecodeOffset, unsigned, getCallReturnOffset>(callIndices.begin(), callIndices.size(), getJITCode().offsetOf(returnAddress.value()))->bytecodeOffset;
+        }
+#endif
+#if ENABLE(INTERPRETER)
+        unsigned bytecodeOffset(Instruction* returnAddress)
+        {
+            return static_cast<Instruction*>(returnAddress) - instructions().begin();
+        }
+#endif
+
+        void setIsNumericCompareFunction(bool isNumericCompareFunction) { m_isNumericCompareFunction = isNumericCompareFunction; }
+        bool isNumericCompareFunction() { return m_isNumericCompareFunction; }
+
+        Vector<Instruction>& instructions() { return m_instructions; }
+        void discardBytecode() { m_instructions.clear(); }
+
+#ifndef NDEBUG
+        unsigned instructionCount() { return m_instructionCount; }
+        void setInstructionCount(unsigned instructionCount) { m_instructionCount = instructionCount; }
+#endif
+
+#if ENABLE(JIT)
+        JITCode& getJITCode() { return m_isConstructor ? ownerExecutable()->generatedJITCodeForConstruct() : ownerExecutable()->generatedJITCodeForCall(); }
+        ExecutablePool* executablePool() { return getJITCode().getExecutablePool(); }
+#endif
+
+        ScriptExecutable* ownerExecutable() const { return m_ownerExecutable; }
+
+        void setGlobalData(JSGlobalData* globalData) { m_globalData = globalData; }
+
+        void setThisRegister(int thisRegister) { m_thisRegister = thisRegister; }
+        int thisRegister() const { return m_thisRegister; }
+
+        void setNeedsFullScopeChain(bool needsFullScopeChain) { m_needsFullScopeChain = needsFullScopeChain; }
+        bool needsFullScopeChain() const { return m_needsFullScopeChain; }
+        void setUsesEval(bool usesEval) { m_usesEval = usesEval; }
+        bool usesEval() const { return m_usesEval; }
+        
+        void setArgumentsRegister(int argumentsRegister)
+        {
+            ASSERT(argumentsRegister != -1);
+            m_argumentsRegister = argumentsRegister;
+            ASSERT(usesArguments());
+        }
+        int argumentsRegister()
+        {
+            ASSERT(usesArguments());
+            return m_argumentsRegister;
+        }
+        void setActivationRegister(int activationRegister)
+        {
+            m_activationRegister = activationRegister;
+        }
+        int activationRegister()
+        {
+            ASSERT(needsFullScopeChain());
+            return m_activationRegister;
+        }
+        bool usesArguments() const { return m_argumentsRegister != -1; }
+
+        CodeType codeType() const { return m_codeType; }
+
+        SourceProvider* source() const { return m_source.get(); }
+        unsigned sourceOffset() const { return m_sourceOffset; }
+
+        size_t numberOfJumpTargets() const { return m_jumpTargets.size(); }
+        void addJumpTarget(unsigned jumpTarget) { m_jumpTargets.append(jumpTarget); }
+        unsigned jumpTarget(int index) const { return m_jumpTargets[index]; }
+        unsigned lastJumpTarget() const { return m_jumpTargets.last(); }
+
+        void createActivation(CallFrame*);
+
+#if ENABLE(INTERPRETER)
+        void addPropertyAccessInstruction(unsigned propertyAccessInstruction) { m_propertyAccessInstructions.append(propertyAccessInstruction); }
+        void addGlobalResolveInstruction(unsigned globalResolveInstruction) { m_globalResolveInstructions.append(globalResolveInstruction); }
+        bool hasGlobalResolveInstructionAtBytecodeOffset(unsigned bytecodeOffset);
+#endif
+#if ENABLE(JIT)
+        size_t numberOfStructureStubInfos() const { return m_structureStubInfos.size(); }
+        void addStructureStubInfo(const StructureStubInfo& stubInfo) { m_structureStubInfos.append(stubInfo); }
+        StructureStubInfo& structureStubInfo(int index) { return m_structureStubInfos[index]; }
+
+        void addGlobalResolveInfo(unsigned globalResolveInstruction) { m_globalResolveInfos.append(GlobalResolveInfo(globalResolveInstruction)); }
+        GlobalResolveInfo& globalResolveInfo(int index) { return m_globalResolveInfos[index]; }
+        bool hasGlobalResolveInfoAtBytecodeOffset(unsigned bytecodeOffset);
+
+        size_t numberOfCallLinkInfos() const { return m_callLinkInfos.size(); }
+        void addCallLinkInfo() { m_callLinkInfos.append(CallLinkInfo()); }
+        CallLinkInfo& callLinkInfo(int index) { return m_callLinkInfos[index]; }
+
+        void addMethodCallLinkInfos(unsigned n) { m_methodCallLinkInfos.grow(n); }
+        MethodCallLinkInfo& methodCallLinkInfo(int index) { return m_methodCallLinkInfos[index]; }
+#endif
+
+        // Exception handling support
+
+        size_t numberOfExceptionHandlers() const { return m_rareData ? m_rareData->m_exceptionHandlers.size() : 0; }
+        void addExceptionHandler(const HandlerInfo& hanler) { createRareDataIfNecessary(); return m_rareData->m_exceptionHandlers.append(hanler); }
+        HandlerInfo& exceptionHandler(int index) { ASSERT(m_rareData); return m_rareData->m_exceptionHandlers[index]; }
+
+        void addExpressionInfo(const ExpressionRangeInfo& expressionInfo)
+        {
+            createRareDataIfNecessary();
+            m_rareData->m_expressionInfo.append(expressionInfo);
+        }
+
+        void addLineInfo(unsigned bytecodeOffset, int lineNo)
+        {
+            createRareDataIfNecessary();
+            Vector<LineInfo>& lineInfo = m_rareData->m_lineInfo;
+            if (!lineInfo.size() || lineInfo.last().lineNumber != lineNo) {
+                LineInfo info = { bytecodeOffset, lineNo };
+                lineInfo.append(info);
+            }
+        }
+
+        bool hasExpressionInfo() { return m_rareData && m_rareData->m_expressionInfo.size(); }
+        bool hasLineInfo() { return m_rareData && m_rareData->m_lineInfo.size(); }
+        bool needsCallReturnIndices()
+        {
+            return m_rareData &&
+                (m_rareData->m_expressionInfo.size() || m_rareData->m_lineInfo.size() || m_rareData->m_exceptionHandlers.size());
+        }
+
+#if ENABLE(JIT)
+        Vector<CallReturnOffsetToBytecodeOffset>& callReturnIndexVector()
+        {
+            createRareDataIfNecessary();
+            return m_rareData->m_callReturnIndexVector;
+        }
+#endif
+
+        // Constant Pool
+
+        size_t numberOfIdentifiers() const { return m_identifiers.size(); }
+        void addIdentifier(const Identifier& i) { return m_identifiers.append(i); }
+        Identifier& identifier(int index) { return m_identifiers[index]; }
+
+        size_t numberOfConstantRegisters() const { return m_constantRegisters.size(); }
+        void addConstantRegister(const Register& r) { return m_constantRegisters.append(r); }
+        Register& constantRegister(int index) { return m_constantRegisters[index - FirstConstantRegisterIndex]; }
+        ALWAYS_INLINE bool isConstantRegisterIndex(int index) const { return index >= FirstConstantRegisterIndex; }
+        ALWAYS_INLINE JSValue getConstant(int index) const { return m_constantRegisters[index - FirstConstantRegisterIndex].jsValue(); }
+
+        unsigned addFunctionDecl(NonNullPassRefPtr<FunctionExecutable> n) { unsigned size = m_functionDecls.size(); m_functionDecls.append(n); return size; }
+        FunctionExecutable* functionDecl(int index) { return m_functionDecls[index].get(); }
+        int numberOfFunctionDecls() { return m_functionDecls.size(); }
+        unsigned addFunctionExpr(NonNullPassRefPtr<FunctionExecutable> n) { unsigned size = m_functionExprs.size(); m_functionExprs.append(n); return size; }
+        FunctionExecutable* functionExpr(int index) { return m_functionExprs[index].get(); }
+
+        unsigned addRegExp(RegExp* r) { createRareDataIfNecessary(); unsigned size = m_rareData->m_regexps.size(); m_rareData->m_regexps.append(r); return size; }
+        RegExp* regexp(int index) const { ASSERT(m_rareData); return m_rareData->m_regexps[index].get(); }
+
+        JSGlobalObject* globalObject() { return m_globalObject; }
+
+        // Jump Tables
+
+        size_t numberOfImmediateSwitchJumpTables() const { return m_rareData ? m_rareData->m_immediateSwitchJumpTables.size() : 0; }
+        SimpleJumpTable& addImmediateSwitchJumpTable() { createRareDataIfNecessary(); m_rareData->m_immediateSwitchJumpTables.append(SimpleJumpTable()); return m_rareData->m_immediateSwitchJumpTables.last(); }
+        SimpleJumpTable& immediateSwitchJumpTable(int tableIndex) { ASSERT(m_rareData); return m_rareData->m_immediateSwitchJumpTables[tableIndex]; }
+
+        size_t numberOfCharacterSwitchJumpTables() const { return m_rareData ? m_rareData->m_characterSwitchJumpTables.size() : 0; }
+        SimpleJumpTable& addCharacterSwitchJumpTable() { createRareDataIfNecessary(); m_rareData->m_characterSwitchJumpTables.append(SimpleJumpTable()); return m_rareData->m_characterSwitchJumpTables.last(); }
+        SimpleJumpTable& characterSwitchJumpTable(int tableIndex) { ASSERT(m_rareData); return m_rareData->m_characterSwitchJumpTables[tableIndex]; }
+
+        size_t numberOfStringSwitchJumpTables() const { return m_rareData ? m_rareData->m_stringSwitchJumpTables.size() : 0; }
+        StringJumpTable& addStringSwitchJumpTable() { createRareDataIfNecessary(); m_rareData->m_stringSwitchJumpTables.append(StringJumpTable()); return m_rareData->m_stringSwitchJumpTables.last(); }
+        StringJumpTable& stringSwitchJumpTable(int tableIndex) { ASSERT(m_rareData); return m_rareData->m_stringSwitchJumpTables[tableIndex]; }
+
+
+        SymbolTable* symbolTable() { return m_symbolTable; }
+        SharedSymbolTable* sharedSymbolTable() { ASSERT(m_codeType == FunctionCode); return static_cast<SharedSymbolTable*>(m_symbolTable); }
+
+        EvalCodeCache& evalCodeCache() { createRareDataIfNecessary(); return m_rareData->m_evalCodeCache; }
+
+        void shrinkToFit();
+
+        // FIXME: Make these remaining members private.
+
+        int m_numCalleeRegisters;
+        int m_numVars;
+        int m_numCapturedVars;
+        int m_numParameters;
+        bool m_isConstructor;
+
+    private:
+#if !defined(NDEBUG) || ENABLE(OPCODE_SAMPLING)
+        void dump(ExecState*, const Vector<Instruction>::const_iterator& begin, Vector<Instruction>::const_iterator&) const;
+
+        CString registerName(ExecState*, int r) const;
+        void printUnaryOp(ExecState*, int location, Vector<Instruction>::const_iterator&, const char* op) const;
+        void printBinaryOp(ExecState*, int location, Vector<Instruction>::const_iterator&, const char* op) const;
+        void printConditionalJump(ExecState*, const Vector<Instruction>::const_iterator&, Vector<Instruction>::const_iterator&, int location, const char* op) const;
+        void printGetByIdOp(ExecState*, int location, Vector<Instruction>::const_iterator&, const char* op) const;
+        void printPutByIdOp(ExecState*, int location, Vector<Instruction>::const_iterator&, const char* op) const;
+#endif
+
+        void createRareDataIfNecessary()
+        {
+            if (!m_rareData)
+                m_rareData = adoptPtr(new RareData);
+        }
+
+        ScriptExecutable* m_ownerExecutable;
+        JSGlobalData* m_globalData;
+
+        Vector<Instruction> m_instructions;
+#ifndef NDEBUG
+        unsigned m_instructionCount;
+#endif
+
+        int m_thisRegister;
+        int m_argumentsRegister;
+        int m_activationRegister;
+
+        bool m_needsFullScopeChain;
+        bool m_usesEval;
+        bool m_isNumericCompareFunction;
+        bool m_isStrictMode;
+
+        CodeType m_codeType;
+
+        RefPtr<SourceProvider> m_source;
+        unsigned m_sourceOffset;
+
+#if ENABLE(INTERPRETER)
+        Vector<unsigned> m_propertyAccessInstructions;
+        Vector<unsigned> m_globalResolveInstructions;
+#endif
+#if ENABLE(JIT)
+        Vector<StructureStubInfo> m_structureStubInfos;
+        Vector<GlobalResolveInfo> m_globalResolveInfos;
+        Vector<CallLinkInfo> m_callLinkInfos;
+        Vector<MethodCallLinkInfo> m_methodCallLinkInfos;
+        Vector<CallLinkInfo*> m_linkedCallerList;
+#endif
+
+        Vector<unsigned> m_jumpTargets;
+
+        // Constant Pool
+        Vector<Identifier> m_identifiers;
+        Vector<Register> m_constantRegisters;
+        Vector<RefPtr<FunctionExecutable> > m_functionDecls;
+        Vector<RefPtr<FunctionExecutable> > m_functionExprs;
+
+        SymbolTable* m_symbolTable;
+
+        struct RareData : FastAllocBase {
+            Vector<HandlerInfo> m_exceptionHandlers;
+
+            // Rare Constants
+            Vector<RefPtr<RegExp> > m_regexps;
+
+            // Jump Tables
+            Vector<SimpleJumpTable> m_immediateSwitchJumpTables;
+            Vector<SimpleJumpTable> m_characterSwitchJumpTables;
+            Vector<StringJumpTable> m_stringSwitchJumpTables;
+
+            EvalCodeCache m_evalCodeCache;
+
+            // Expression info - present if debugging.
+            Vector<ExpressionRangeInfo> m_expressionInfo;
+            // Line info - present if profiling or debugging.
+            Vector<LineInfo> m_lineInfo;
+#if ENABLE(JIT)
+            Vector<CallReturnOffsetToBytecodeOffset> m_callReturnIndexVector;
+#endif
+        };
+        OwnPtr<RareData> m_rareData;
+    };
+
+    // Program code is not marked by any function, so we make the global object
+    // responsible for marking it.
+
+    class GlobalCodeBlock : public CodeBlock {
+    public:
+        GlobalCodeBlock(ScriptExecutable* ownerExecutable, CodeType codeType, JSGlobalObject* globalObject, PassRefPtr<SourceProvider> sourceProvider, unsigned sourceOffset)
+            : CodeBlock(ownerExecutable, codeType, globalObject, sourceProvider, sourceOffset, &m_unsharedSymbolTable, false)
+        {
+            m_globalObject->codeBlocks().add(this);
+        }
+
+        ~GlobalCodeBlock()
+        {
+            if (m_globalObject)
+                m_globalObject->codeBlocks().remove(this);
+        }
+
+        void clearGlobalObject() { m_globalObject = 0; }
+
+    private:
+        SymbolTable m_unsharedSymbolTable;
+    };
+
+    class ProgramCodeBlock : public GlobalCodeBlock {
+    public:
+        ProgramCodeBlock(ProgramExecutable* ownerExecutable, CodeType codeType, JSGlobalObject* globalObject, PassRefPtr<SourceProvider> sourceProvider)
+            : GlobalCodeBlock(ownerExecutable, codeType, globalObject, sourceProvider, 0)
+        {
+        }
+    };
+
+    class EvalCodeBlock : public GlobalCodeBlock {
+    public:
+        EvalCodeBlock(EvalExecutable* ownerExecutable, JSGlobalObject* globalObject, PassRefPtr<SourceProvider> sourceProvider, int baseScopeDepth)
+            : GlobalCodeBlock(ownerExecutable, EvalCode, globalObject, sourceProvider, 0)
+            , m_baseScopeDepth(baseScopeDepth)
+        {
+        }
+
+        int baseScopeDepth() const { return m_baseScopeDepth; }
+
+        const Identifier& variable(unsigned index) { return m_variables[index]; }
+        unsigned numVariables() { return m_variables.size(); }
+        void adoptVariables(Vector<Identifier>& variables)
+        {
+            ASSERT(m_variables.isEmpty());
+            m_variables.swap(variables);
+        }
+
+    private:
+        int m_baseScopeDepth;
+        Vector<Identifier> m_variables;
+    };
+
+    class FunctionCodeBlock : public CodeBlock {
+    public:
+        // Rather than using the usual RefCounted::create idiom for SharedSymbolTable we just use new
+        // as we need to initialise the CodeBlock before we could initialise any RefPtr to hold the shared
+        // symbol table, so we just pass as a raw pointer with a ref count of 1.  We then manually deref
+        // in the destructor.
+        FunctionCodeBlock(FunctionExecutable* ownerExecutable, CodeType codeType, JSGlobalObject* globalObject, PassRefPtr<SourceProvider> sourceProvider, unsigned sourceOffset, bool isConstructor)
+            : CodeBlock(ownerExecutable, codeType, globalObject, sourceProvider, sourceOffset, SharedSymbolTable::create().leakRef(), isConstructor)
+        {
+        }
+        ~FunctionCodeBlock()
+        {
+            sharedSymbolTable()->deref();
+        }
+    };
+
+    inline Register& ExecState::r(int index)
+    {
+        CodeBlock* codeBlock = this->codeBlock();
+        if (codeBlock->isConstantRegisterIndex(index))
+            return codeBlock->constantRegister(index);
+        return this[index];
+    }
+
+    inline Register& ExecState::uncheckedR(int index)
+    {
+        ASSERT(index < FirstConstantRegisterIndex);
+        return this[index];
+    }
+    
+} // namespace JSC
+
+#endif // CodeBlock_h
diff --git a/Source/JavaScriptCore/bytecode/EvalCodeCache.h b/Source/JavaScriptCore/bytecode/EvalCodeCache.h
new file mode 100644
index 0000000..edd575f
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/EvalCodeCache.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef EvalCodeCache_h
+#define EvalCodeCache_h
+
+#include "Executable.h"
+#include "JSGlobalObject.h"
+#include "Nodes.h"
+#include "Parser.h"
+#include "SourceCode.h"
+#include "UString.h"
+#include <wtf/HashMap.h>
+#include <wtf/RefPtr.h>
+#include <wtf/text/StringHash.h>
+
+namespace JSC {
+
+    class EvalCodeCache {
+    public:
+        PassRefPtr<EvalExecutable> get(ExecState* exec, bool inStrictContext, const UString& evalSource, ScopeChainNode* scopeChain, JSValue& exceptionValue)
+        {
+            RefPtr<EvalExecutable> evalExecutable;
+
+            if (!inStrictContext && evalSource.length() < maxCacheableSourceLength && (*scopeChain->begin())->isVariableObject())
+                evalExecutable = m_cacheMap.get(evalSource.impl());
+
+            if (!evalExecutable) {
+                evalExecutable = EvalExecutable::create(exec, makeSource(evalSource), inStrictContext);
+                exceptionValue = evalExecutable->compile(exec, scopeChain);
+                if (exceptionValue)
+                    return 0;
+
+                if (!inStrictContext && evalSource.length() < maxCacheableSourceLength && (*scopeChain->begin())->isVariableObject() && m_cacheMap.size() < maxCacheEntries)
+                    m_cacheMap.set(evalSource.impl(), evalExecutable);
+            }
+
+            return evalExecutable.release();
+        }
+
+        bool isEmpty() const { return m_cacheMap.isEmpty(); }
+
+    private:
+        static const unsigned maxCacheableSourceLength = 256;
+        static const int maxCacheEntries = 64;
+
+        typedef HashMap<RefPtr<StringImpl>, RefPtr<EvalExecutable> > EvalCacheMap;
+        EvalCacheMap m_cacheMap;
+    };
+
+} // namespace JSC
+
+#endif // EvalCodeCache_h
diff --git a/Source/JavaScriptCore/bytecode/Instruction.h b/Source/JavaScriptCore/bytecode/Instruction.h
new file mode 100644
index 0000000..c6468a5
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/Instruction.h
@@ -0,0 +1,169 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef Instruction_h
+#define Instruction_h
+
+#include "MacroAssembler.h"
+#include "Opcode.h"
+#include "PropertySlot.h"
+#include "Structure.h"
+#include <wtf/VectorTraits.h>
+
+#define POLYMORPHIC_LIST_CACHE_SIZE 8
+
+namespace JSC {
+
+    // *Sigh*, If the JIT is enabled we need to track the stubRountine (of type CodeLocationLabel),
+    // If the JIT is not in use we don't actually need the variable (that said, if the JIT is not in use we don't
+    // curently actually use PolymorphicAccessStructureLists, which we should).  Anyway, this seems like the best
+    // solution for now - will need to something smarter if/when we actually want mixed-mode operation.
+#if ENABLE(JIT)
+    typedef CodeLocationLabel PolymorphicAccessStructureListStubRoutineType;
+#else
+    typedef void* PolymorphicAccessStructureListStubRoutineType;
+#endif
+
+    class JSCell;
+    class Structure;
+    class StructureChain;
+
+    // Structure used by op_get_by_id_self_list and op_get_by_id_proto_list instruction to hold data off the main opcode stream.
+    struct PolymorphicAccessStructureList : FastAllocBase {
+        struct PolymorphicStubInfo {
+            bool isChain;
+            PolymorphicAccessStructureListStubRoutineType stubRoutine;
+            Structure* base;
+            union {
+                Structure* proto;
+                StructureChain* chain;
+            } u;
+
+            void set(PolymorphicAccessStructureListStubRoutineType _stubRoutine, Structure* _base)
+            {
+                stubRoutine = _stubRoutine;
+                base = _base;
+                u.proto = 0;
+                isChain = false;
+            }
+            
+            void set(PolymorphicAccessStructureListStubRoutineType _stubRoutine, Structure* _base, Structure* _proto)
+            {
+                stubRoutine = _stubRoutine;
+                base = _base;
+                u.proto = _proto;
+                isChain = false;
+            }
+            
+            void set(PolymorphicAccessStructureListStubRoutineType _stubRoutine, Structure* _base, StructureChain* _chain)
+            {
+                stubRoutine = _stubRoutine;
+                base = _base;
+                u.chain = _chain;
+                isChain = true;
+            }
+        } list[POLYMORPHIC_LIST_CACHE_SIZE];
+        
+        PolymorphicAccessStructureList(PolymorphicAccessStructureListStubRoutineType stubRoutine, Structure* firstBase)
+        {
+            list[0].set(stubRoutine, firstBase);
+        }
+
+        PolymorphicAccessStructureList(PolymorphicAccessStructureListStubRoutineType stubRoutine, Structure* firstBase, Structure* firstProto)
+        {
+            list[0].set(stubRoutine, firstBase, firstProto);
+        }
+
+        PolymorphicAccessStructureList(PolymorphicAccessStructureListStubRoutineType stubRoutine, Structure* firstBase, StructureChain* firstChain)
+        {
+            list[0].set(stubRoutine, firstBase, firstChain);
+        }
+
+        void derefStructures(int count)
+        {
+            for (int i = 0; i < count; ++i) {
+                PolymorphicStubInfo& info = list[i];
+
+                ASSERT(info.base);
+                info.base->deref();
+
+                if (info.u.proto) {
+                    if (info.isChain)
+                        info.u.chain->deref();
+                    else
+                        info.u.proto->deref();
+                }
+            }
+        }
+    };
+
+    struct Instruction {
+        Instruction(Opcode opcode)
+        {
+#if !ENABLE(COMPUTED_GOTO_INTERPRETER)
+            // We have to initialize one of the pointer members to ensure that
+            // the entire struct is initialized, when opcode is not a pointer.
+            u.jsCell = 0;
+#endif
+            u.opcode = opcode;
+        }
+
+        Instruction(int operand)
+        {
+            // We have to initialize one of the pointer members to ensure that
+            // the entire struct is initialized in 64-bit.
+            u.jsCell = 0;
+            u.operand = operand;
+        }
+
+        Instruction(Structure* structure) { u.structure = structure; }
+        Instruction(StructureChain* structureChain) { u.structureChain = structureChain; }
+        Instruction(JSCell* jsCell) { u.jsCell = jsCell; }
+        Instruction(PolymorphicAccessStructureList* polymorphicStructures) { u.polymorphicStructures = polymorphicStructures; }
+        Instruction(PropertySlot::GetValueFunc getterFunc) { u.getterFunc = getterFunc; }
+
+        union {
+            Opcode opcode;
+            int operand;
+            Structure* structure;
+            StructureChain* structureChain;
+            JSCell* jsCell;
+            PolymorphicAccessStructureList* polymorphicStructures;
+            PropertySlot::GetValueFunc getterFunc;
+        } u;
+    };
+
+} // namespace JSC
+
+namespace WTF {
+
+    template<> struct VectorTraits<JSC::Instruction> : VectorTraitsBase<true, JSC::Instruction> { };
+
+} // namespace WTF
+
+#endif // Instruction_h
diff --git a/Source/JavaScriptCore/bytecode/JumpTable.cpp b/Source/JavaScriptCore/bytecode/JumpTable.cpp
new file mode 100644
index 0000000..ef7098b
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/JumpTable.cpp
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All rights reserved.
+ * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "JumpTable.h"
+
+#include <wtf/text/StringHash.h>
+
+namespace JSC {
+
+int32_t SimpleJumpTable::offsetForValue(int32_t value, int32_t defaultOffset)
+{
+    if (value >= min && static_cast<uint32_t>(value - min) < branchOffsets.size()) {
+        int32_t offset = branchOffsets[value - min];
+        if (offset)
+            return offset;
+    }
+    return defaultOffset;        
+}
+
+} // namespace JSC
diff --git a/Source/JavaScriptCore/bytecode/JumpTable.h b/Source/JavaScriptCore/bytecode/JumpTable.h
new file mode 100644
index 0000000..5bbe047
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/JumpTable.h
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All rights reserved.
+ * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef JumpTable_h
+#define JumpTable_h
+
+#include "MacroAssembler.h"
+#include "UString.h"
+#include <wtf/HashMap.h>
+#include <wtf/Vector.h>
+
+namespace JSC {
+
+    struct OffsetLocation {
+        int32_t branchOffset;
+#if ENABLE(JIT)
+        CodeLocationLabel ctiOffset;
+#endif
+    };
+
+    struct StringJumpTable {
+        typedef HashMap<RefPtr<StringImpl>, OffsetLocation> StringOffsetTable;
+        StringOffsetTable offsetTable;
+#if ENABLE(JIT)
+        CodeLocationLabel ctiDefault; // FIXME: it should not be necessary to store this.
+#endif
+
+        inline int32_t offsetForValue(StringImpl* value, int32_t defaultOffset)
+        {
+            StringOffsetTable::const_iterator end = offsetTable.end();
+            StringOffsetTable::const_iterator loc = offsetTable.find(value);
+            if (loc == end)
+                return defaultOffset;
+            return loc->second.branchOffset;
+        }
+
+#if ENABLE(JIT)
+        inline CodeLocationLabel ctiForValue(StringImpl* value)
+        {
+            StringOffsetTable::const_iterator end = offsetTable.end();
+            StringOffsetTable::const_iterator loc = offsetTable.find(value);
+            if (loc == end)
+                return ctiDefault;
+            return loc->second.ctiOffset;
+        }
+#endif
+    };
+
+    struct SimpleJumpTable {
+        // FIXME: The two Vectors can be combind into one Vector<OffsetLocation>
+        Vector<int32_t> branchOffsets;
+        int32_t min;
+#if ENABLE(JIT)
+        Vector<CodeLocationLabel> ctiOffsets;
+        CodeLocationLabel ctiDefault;
+#endif
+
+        int32_t offsetForValue(int32_t value, int32_t defaultOffset);
+        void add(int32_t key, int32_t offset)
+        {
+            if (!branchOffsets[key])
+                branchOffsets[key] = offset;
+        }
+
+#if ENABLE(JIT)
+        inline CodeLocationLabel ctiForValue(int32_t value)
+        {
+            if (value >= min && static_cast<uint32_t>(value - min) < ctiOffsets.size())
+                return ctiOffsets[value - min];
+            return ctiDefault;
+        }
+#endif
+    };
+
+} // namespace JSC
+
+#endif // JumpTable_h
diff --git a/Source/JavaScriptCore/bytecode/Opcode.cpp b/Source/JavaScriptCore/bytecode/Opcode.cpp
new file mode 100644
index 0000000..0bb714b
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/Opcode.cpp
@@ -0,0 +1,191 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All rights reserved.
+ * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "Opcode.h"
+
+#if ENABLE(OPCODE_STATS)
+#include <stdio.h>
+#include <wtf/FixedArray.h>
+#endif
+
+using namespace std;
+
+namespace JSC {
+
+#if ENABLE(OPCODE_SAMPLING) || ENABLE(CODEBLOCK_SAMPLING) || ENABLE(OPCODE_STATS)
+
+const char* const opcodeNames[] = {
+#define OPCODE_NAME_ENTRY(opcode, size) #opcode,
+    FOR_EACH_OPCODE_ID(OPCODE_NAME_ENTRY)
+#undef OPCODE_NAME_ENTRY
+};
+
+#endif
+
+#if ENABLE(OPCODE_STATS)
+
+long long OpcodeStats::opcodeCounts[numOpcodeIDs];
+long long OpcodeStats::opcodePairCounts[numOpcodeIDs][numOpcodeIDs];
+int OpcodeStats::lastOpcode = -1;
+
+static OpcodeStats logger;
+
+OpcodeStats::OpcodeStats()
+{
+    for (int i = 0; i < numOpcodeIDs; ++i)
+        opcodeCounts[i] = 0;
+    
+    for (int i = 0; i < numOpcodeIDs; ++i)
+        for (int j = 0; j < numOpcodeIDs; ++j)
+            opcodePairCounts[i][j] = 0;
+}
+
+static int compareOpcodeIndices(const void* left, const void* right)
+{
+    long long leftValue = OpcodeStats::opcodeCounts[*(int*) left];
+    long long rightValue = OpcodeStats::opcodeCounts[*(int*) right];
+    
+    if (leftValue < rightValue)
+        return 1;
+    else if (leftValue > rightValue)
+        return -1;
+    else
+        return 0;
+}
+
+static int compareOpcodePairIndices(const void* left, const void* right)
+{
+    pair<int, int> leftPair = *(pair<int, int>*) left;
+    long long leftValue = OpcodeStats::opcodePairCounts[leftPair.first][leftPair.second];
+    pair<int, int> rightPair = *(pair<int, int>*) right;
+    long long rightValue = OpcodeStats::opcodePairCounts[rightPair.first][rightPair.second];
+    
+    if (leftValue < rightValue)
+        return 1;
+    else if (leftValue > rightValue)
+        return -1;
+    else
+        return 0;
+}
+
+OpcodeStats::~OpcodeStats()
+{
+    long long totalInstructions = 0;
+    for (int i = 0; i < numOpcodeIDs; ++i)
+        totalInstructions += opcodeCounts[i];
+    
+    long long totalInstructionPairs = 0;
+    for (int i = 0; i < numOpcodeIDs; ++i)
+        for (int j = 0; j < numOpcodeIDs; ++j)
+            totalInstructionPairs += opcodePairCounts[i][j];
+
+    FixedArray<int, numOpcodeIDs> sortedIndices;
+    for (int i = 0; i < numOpcodeIDs; ++i)
+        sortedIndices[i] = i;
+    qsort(sortedIndices.data(), numOpcodeIDs, sizeof(int), compareOpcodeIndices);
+    
+    pair<int, int> sortedPairIndices[numOpcodeIDs * numOpcodeIDs];
+    pair<int, int>* currentPairIndex = sortedPairIndices;
+    for (int i = 0; i < numOpcodeIDs; ++i)
+        for (int j = 0; j < numOpcodeIDs; ++j)
+            *(currentPairIndex++) = make_pair(i, j);
+    qsort(sortedPairIndices, numOpcodeIDs * numOpcodeIDs, sizeof(pair<int, int>), compareOpcodePairIndices);
+    
+    printf("\nExecuted opcode statistics\n"); 
+    
+    printf("Total instructions executed: %lld\n\n", totalInstructions);
+
+    printf("All opcodes by frequency:\n\n");
+
+    for (int i = 0; i < numOpcodeIDs; ++i) {
+        int index = sortedIndices[i];
+        printf("%s:%s %lld - %.2f%%\n", opcodeNames[index], padOpcodeName((OpcodeID)index, 28), opcodeCounts[index], ((double) opcodeCounts[index]) / ((double) totalInstructions) * 100.0);    
+    }
+    
+    printf("\n");
+    printf("2-opcode sequences by frequency: %lld\n\n", totalInstructions);
+    
+    for (int i = 0; i < numOpcodeIDs * numOpcodeIDs; ++i) {
+        pair<int, int> indexPair = sortedPairIndices[i];
+        long long count = opcodePairCounts[indexPair.first][indexPair.second];
+        
+        if (!count)
+            break;
+        
+        printf("%s%s %s:%s %lld %.2f%%\n", opcodeNames[indexPair.first], padOpcodeName((OpcodeID)indexPair.first, 28), opcodeNames[indexPair.second], padOpcodeName((OpcodeID)indexPair.second, 28), count, ((double) count) / ((double) totalInstructionPairs) * 100.0);
+    }
+    
+    printf("\n");
+    printf("Most common opcodes and sequences:\n");
+
+    for (int i = 0; i < numOpcodeIDs; ++i) {
+        int index = sortedIndices[i];
+        long long opcodeCount = opcodeCounts[index];
+        double opcodeProportion = ((double) opcodeCount) / ((double) totalInstructions);
+        if (opcodeProportion < 0.0001)
+            break;
+        printf("\n%s:%s %lld - %.2f%%\n", opcodeNames[index], padOpcodeName((OpcodeID)index, 28), opcodeCount, opcodeProportion * 100.0);
+
+        for (int j = 0; j < numOpcodeIDs * numOpcodeIDs; ++j) {
+            pair<int, int> indexPair = sortedPairIndices[j];
+            long long pairCount = opcodePairCounts[indexPair.first][indexPair.second];
+            double pairProportion = ((double) pairCount) / ((double) totalInstructionPairs);
+        
+            if (!pairCount || pairProportion < 0.0001 || pairProportion < opcodeProportion / 100)
+                break;
+
+            if (indexPair.first != index && indexPair.second != index)
+                continue;
+
+            printf("    %s%s %s:%s %lld - %.2f%%\n", opcodeNames[indexPair.first], padOpcodeName((OpcodeID)indexPair.first, 28), opcodeNames[indexPair.second], padOpcodeName((OpcodeID)indexPair.second, 28), pairCount, pairProportion * 100.0);
+        }
+        
+    }
+    printf("\n");
+}
+
+void OpcodeStats::recordInstruction(int opcode)
+{
+    opcodeCounts[opcode]++;
+    
+    if (lastOpcode != -1)
+        opcodePairCounts[lastOpcode][opcode]++;
+    
+    lastOpcode = opcode;
+}
+
+void OpcodeStats::resetLastInstruction()
+{
+    lastOpcode = -1;
+}
+
+#endif
+
+} // namespace JSC
diff --git a/Source/JavaScriptCore/bytecode/Opcode.h b/Source/JavaScriptCore/bytecode/Opcode.h
new file mode 100644
index 0000000..6c1c6b2
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/Opcode.h
@@ -0,0 +1,276 @@
+/*
+ * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
+ * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef Opcode_h
+#define Opcode_h
+
+#include <algorithm>
+#include <string.h>
+
+#include <wtf/Assertions.h>
+
+namespace JSC {
+
+    #define FOR_EACH_OPCODE_ID(macro) \
+        macro(op_enter, 1) \
+        macro(op_create_activation, 2) \
+        macro(op_init_lazy_reg, 2) \
+        macro(op_create_arguments, 2) \
+        macro(op_create_this, 3) \
+        macro(op_get_callee, 2) \
+        macro(op_convert_this, 2) \
+        macro(op_convert_this_strict, 2) \
+        \
+        macro(op_new_object, 2) \
+        macro(op_new_array, 4) \
+        macro(op_new_regexp, 3) \
+        macro(op_mov, 3) \
+        \
+        macro(op_not, 3) \
+        macro(op_eq, 4) \
+        macro(op_eq_null, 3) \
+        macro(op_neq, 4) \
+        macro(op_neq_null, 3) \
+        macro(op_stricteq, 4) \
+        macro(op_nstricteq, 4) \
+        macro(op_less, 4) \
+        macro(op_lesseq, 4) \
+        \
+        macro(op_pre_inc, 2) \
+        macro(op_pre_dec, 2) \
+        macro(op_post_inc, 3) \
+        macro(op_post_dec, 3) \
+        macro(op_to_jsnumber, 3) \
+        macro(op_negate, 3) \
+        macro(op_add, 5) \
+        macro(op_mul, 5) \
+        macro(op_div, 5) \
+        macro(op_mod, 4) \
+        macro(op_sub, 5) \
+        \
+        macro(op_lshift, 4) \
+        macro(op_rshift, 4) \
+        macro(op_urshift, 4) \
+        macro(op_bitand, 5) \
+        macro(op_bitxor, 5) \
+        macro(op_bitor, 5) \
+        macro(op_bitnot, 3) \
+        \
+        macro(op_check_has_instance, 2) \
+        macro(op_instanceof, 5) \
+        macro(op_typeof, 3) \
+        macro(op_is_undefined, 3) \
+        macro(op_is_boolean, 3) \
+        macro(op_is_number, 3) \
+        macro(op_is_string, 3) \
+        macro(op_is_object, 3) \
+        macro(op_is_function, 3) \
+        macro(op_in, 4) \
+        \
+        macro(op_resolve, 3) \
+        macro(op_resolve_skip, 4) \
+        macro(op_resolve_global, 5) \
+        macro(op_resolve_global_dynamic, 6) \
+        macro(op_get_scoped_var, 4) \
+        macro(op_put_scoped_var, 4) \
+        macro(op_get_global_var, 3) \
+        macro(op_put_global_var, 3) \
+        macro(op_resolve_base, 4) \
+        macro(op_ensure_property_exists, 3) \
+        macro(op_resolve_with_base, 4) \
+        macro(op_get_by_id, 8) \
+        macro(op_get_by_id_self, 8) \
+        macro(op_get_by_id_self_list, 8) \
+        macro(op_get_by_id_proto, 8) \
+        macro(op_get_by_id_proto_list, 8) \
+        macro(op_get_by_id_chain, 8) \
+        macro(op_get_by_id_getter_self, 8) \
+        macro(op_get_by_id_getter_self_list, 8) \
+        macro(op_get_by_id_getter_proto, 8) \
+        macro(op_get_by_id_getter_proto_list, 8) \
+        macro(op_get_by_id_getter_chain, 8) \
+        macro(op_get_by_id_custom_self, 8) \
+        macro(op_get_by_id_custom_self_list, 8) \
+        macro(op_get_by_id_custom_proto, 8) \
+        macro(op_get_by_id_custom_proto_list, 8) \
+        macro(op_get_by_id_custom_chain, 8) \
+        macro(op_get_by_id_generic, 8) \
+        macro(op_get_array_length, 8) \
+        macro(op_get_string_length, 8) \
+        macro(op_get_arguments_length, 4) \
+        macro(op_put_by_id, 9) \
+        macro(op_put_by_id_transition, 9) \
+        macro(op_put_by_id_replace, 9) \
+        macro(op_put_by_id_generic, 9) \
+        macro(op_del_by_id, 4) \
+        macro(op_get_by_val, 4) \
+        macro(op_get_argument_by_val, 4) \
+        macro(op_get_by_pname, 7) \
+        macro(op_put_by_val, 4) \
+        macro(op_del_by_val, 4) \
+        macro(op_put_by_index, 4) \
+        macro(op_put_getter, 4) \
+        macro(op_put_setter, 4) \
+        \
+        macro(op_jmp, 2) \
+        macro(op_jtrue, 3) \
+        macro(op_jfalse, 3) \
+        macro(op_jeq_null, 3) \
+        macro(op_jneq_null, 3) \
+        macro(op_jneq_ptr, 4) \
+        macro(op_jnless, 4) \
+        macro(op_jnlesseq, 4) \
+        macro(op_jless, 4) \
+        macro(op_jlesseq, 4) \
+        macro(op_jmp_scopes, 3) \
+        macro(op_loop, 2) \
+        macro(op_loop_if_true, 3) \
+        macro(op_loop_if_false, 3) \
+        macro(op_loop_if_less, 4) \
+        macro(op_loop_if_lesseq, 4) \
+        macro(op_switch_imm, 4) \
+        macro(op_switch_char, 4) \
+        macro(op_switch_string, 4) \
+        \
+        macro(op_new_func, 4) \
+        macro(op_new_func_exp, 3) \
+        macro(op_call, 4) \
+        macro(op_call_eval, 4) \
+        macro(op_call_varargs, 4) \
+        macro(op_load_varargs, 4) \
+        macro(op_tear_off_activation, 3) \
+        macro(op_tear_off_arguments, 2) \
+        macro(op_ret, 2) \
+        macro(op_call_put_result, 2) \
+        macro(op_ret_object_or_this, 3) \
+        macro(op_method_check, 1) \
+        \
+        macro(op_construct, 4) \
+        macro(op_strcat, 4) \
+        macro(op_to_primitive, 3) \
+        \
+        macro(op_get_pnames, 6) \
+        macro(op_next_pname, 7) \
+        \
+        macro(op_push_scope, 2) \
+        macro(op_pop_scope, 1) \
+        macro(op_push_new_scope, 4) \
+        \
+        macro(op_catch, 2) \
+        macro(op_throw, 2) \
+        macro(op_throw_reference_error, 2) \
+        macro(op_throw_syntax_error, 2) \
+        \
+        macro(op_jsr, 3) \
+        macro(op_sret, 2) \
+        \
+        macro(op_debug, 4) \
+        macro(op_profile_will_call, 2) \
+        macro(op_profile_did_call, 2) \
+        \
+        macro(op_end, 2) // end must be the last opcode in the list
+
+    #define OPCODE_ID_ENUM(opcode, length) opcode,
+        typedef enum { FOR_EACH_OPCODE_ID(OPCODE_ID_ENUM) } OpcodeID;
+    #undef OPCODE_ID_ENUM
+
+    const int numOpcodeIDs = op_end + 1;
+
+    #define OPCODE_ID_LENGTHS(id, length) const int id##_length = length;
+         FOR_EACH_OPCODE_ID(OPCODE_ID_LENGTHS);
+    #undef OPCODE_ID_LENGTHS
+    
+    #define OPCODE_LENGTH(opcode) opcode##_length
+
+    #define OPCODE_ID_LENGTH_MAP(opcode, length) length,
+        const int opcodeLengths[numOpcodeIDs] = { FOR_EACH_OPCODE_ID(OPCODE_ID_LENGTH_MAP) };
+    #undef OPCODE_ID_LENGTH_MAP
+
+    #define VERIFY_OPCODE_ID(id, size) COMPILE_ASSERT(id <= op_end, ASSERT_THAT_JS_OPCODE_IDS_ARE_VALID);
+        FOR_EACH_OPCODE_ID(VERIFY_OPCODE_ID);
+    #undef VERIFY_OPCODE_ID
+
+#if ENABLE(COMPUTED_GOTO_INTERPRETER)
+#if COMPILER(RVCT) || COMPILER(INTEL)
+    typedef void* Opcode;
+#else
+    typedef const void* Opcode;
+#endif
+#else
+    typedef OpcodeID Opcode;
+#endif
+
+#if ENABLE(OPCODE_SAMPLING) || ENABLE(CODEBLOCK_SAMPLING) || ENABLE(OPCODE_STATS)
+
+#define PADDING_STRING "                                "
+#define PADDING_STRING_LENGTH static_cast<unsigned>(strlen(PADDING_STRING))
+
+    extern const char* const opcodeNames[];
+
+    inline const char* padOpcodeName(OpcodeID op, unsigned width)
+    {
+        unsigned pad = width - strlen(opcodeNames[op]);
+        pad = std::min(pad, PADDING_STRING_LENGTH);
+        return PADDING_STRING + PADDING_STRING_LENGTH - pad;
+    }
+
+#undef PADDING_STRING_LENGTH
+#undef PADDING_STRING
+
+#endif
+
+#if ENABLE(OPCODE_STATS)
+
+    struct OpcodeStats {
+        OpcodeStats();
+        ~OpcodeStats();
+        static long long opcodeCounts[numOpcodeIDs];
+        static long long opcodePairCounts[numOpcodeIDs][numOpcodeIDs];
+        static int lastOpcode;
+
+        static void recordInstruction(int opcode);
+        static void resetLastInstruction();
+    };
+
+#endif
+
+    inline size_t opcodeLength(OpcodeID opcode)
+    {
+        switch (opcode) {
+#define OPCODE_ID_LENGTHS(id, length) case id: return OPCODE_LENGTH(id);
+             FOR_EACH_OPCODE_ID(OPCODE_ID_LENGTHS)
+#undef OPCODE_ID_LENGTHS
+        }
+        ASSERT_NOT_REACHED();
+        return 0;
+    }
+
+} // namespace JSC
+
+#endif // Opcode_h
diff --git a/Source/JavaScriptCore/bytecode/SamplingTool.cpp b/Source/JavaScriptCore/bytecode/SamplingTool.cpp
new file mode 100644
index 0000000..f47e698
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/SamplingTool.cpp
@@ -0,0 +1,406 @@
+/*
+ * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "SamplingTool.h"
+
+#include "CodeBlock.h"
+#include "Interpreter.h"
+#include "Opcode.h"
+
+#if !OS(WINDOWS)
+#include <unistd.h>
+#endif
+
+namespace JSC {
+
+#if ENABLE(SAMPLING_FLAGS)
+
+void SamplingFlags::sample()
+{
+    uint32_t mask = static_cast<uint32_t>(1 << 31);
+    unsigned index;
+
+    for (index = 0; index < 32; ++index) {
+        if (mask & s_flags)
+            break;
+        mask >>= 1;
+    }
+
+    s_flagCounts[32 - index]++;
+}
+
+void SamplingFlags::start()
+{
+    for (unsigned i = 0; i <= 32; ++i)
+        s_flagCounts[i] = 0;
+}
+void SamplingFlags::stop()
+{
+    uint64_t total = 0;
+    for (unsigned i = 0; i <= 32; ++i)
+        total += s_flagCounts[i];
+
+    if (total) {
+        printf("\nSamplingFlags: sample counts with flags set: (%lld total)\n", total);
+        for (unsigned i = 0; i <= 32; ++i) {
+            if (s_flagCounts[i])
+                printf("  [ %02d ] : %lld\t\t(%03.2f%%)\n", i, s_flagCounts[i], (100.0 * s_flagCounts[i]) / total);
+        }
+        printf("\n");
+    } else
+    printf("\nSamplingFlags: no samples.\n\n");
+}
+uint64_t SamplingFlags::s_flagCounts[33];
+
+#else
+void SamplingFlags::start() {}
+void SamplingFlags::stop() {}
+#endif
+
+/*
+  Start with flag 16 set.
+  By doing this the monitoring of lower valued flags will be masked out
+  until flag 16 is explictly cleared.
+*/
+uint32_t SamplingFlags::s_flags = 1 << 15;
+
+
+#if OS(WINDOWS)
+
+static void sleepForMicroseconds(unsigned us)
+{
+    unsigned ms = us / 1000;
+    if (us && !ms)
+        ms = 1;
+    Sleep(ms);
+}
+
+#else 
+
+static void sleepForMicroseconds(unsigned us)
+{
+    usleep(us);
+}
+
+#endif
+
+static inline unsigned hertz2us(unsigned hertz)
+{
+    return 1000000 / hertz;
+}
+
+
+SamplingTool* SamplingTool::s_samplingTool = 0;
+
+
+bool SamplingThread::s_running = false;
+unsigned SamplingThread::s_hertz = 10000;
+ThreadIdentifier SamplingThread::s_samplingThread;
+
+void* SamplingThread::threadStartFunc(void*)
+{
+    while (s_running) {
+        sleepForMicroseconds(hertz2us(s_hertz));
+
+#if ENABLE(SAMPLING_FLAGS)
+        SamplingFlags::sample();
+#endif
+#if ENABLE(OPCODE_SAMPLING)
+        SamplingTool::sample();
+#endif
+    }
+
+    return 0;
+}
+
+
+void SamplingThread::start(unsigned hertz)
+{
+    ASSERT(!s_running);
+    s_running = true;
+    s_hertz = hertz;
+
+    s_samplingThread = createThread(threadStartFunc, 0, "JavaScriptCore::Sampler");
+}
+
+void SamplingThread::stop()
+{
+    ASSERT(s_running);
+    s_running = false;
+    waitForThreadCompletion(s_samplingThread, 0);
+}
+
+
+void ScriptSampleRecord::sample(CodeBlock* codeBlock, Instruction* vPC)
+{
+    if (!m_samples) {
+        m_size = codeBlock->instructions().size();
+        m_samples = static_cast<int*>(calloc(m_size, sizeof(int)));
+        m_codeBlock = codeBlock;
+    }
+
+    ++m_sampleCount;
+
+    unsigned offest = vPC - codeBlock->instructions().begin();
+    // Since we don't read and write codeBlock and vPC atomically, this check
+    // can fail if we sample mid op_call / op_ret.
+    if (offest < m_size) {
+        m_samples[offest]++;
+        m_opcodeSampleCount++;
+    }
+}
+
+void SamplingTool::doRun()
+{
+    Sample sample(m_sample, m_codeBlock);
+    ++m_sampleCount;
+
+    if (sample.isNull())
+        return;
+
+    if (!sample.inHostFunction()) {
+        unsigned opcodeID = m_interpreter->getOpcodeID(sample.vPC()[0].u.opcode);
+
+        ++m_opcodeSampleCount;
+        ++m_opcodeSamples[opcodeID];
+
+        if (sample.inCTIFunction())
+            m_opcodeSamplesInCTIFunctions[opcodeID]++;
+    }
+
+#if ENABLE(CODEBLOCK_SAMPLING)
+    if (CodeBlock* codeBlock = sample.codeBlock()) {
+        MutexLocker locker(m_scriptSampleMapMutex);
+        ScriptSampleRecord* record = m_scopeSampleMap->get(codeBlock->ownerExecutable());
+        ASSERT(record);
+        record->sample(codeBlock, sample.vPC());
+    }
+#endif
+}
+
+void SamplingTool::sample()
+{
+    s_samplingTool->doRun();
+}
+
+void SamplingTool::notifyOfScope(ScriptExecutable* script)
+{
+#if ENABLE(CODEBLOCK_SAMPLING)
+    MutexLocker locker(m_scriptSampleMapMutex);
+    m_scopeSampleMap->set(script, new ScriptSampleRecord(script));
+#else
+    UNUSED_PARAM(script);
+#endif
+}
+
+void SamplingTool::setup()
+{
+    s_samplingTool = this;
+}
+
+#if ENABLE(OPCODE_SAMPLING)
+
+struct OpcodeSampleInfo {
+    OpcodeID opcode;
+    long long count;
+    long long countInCTIFunctions;
+};
+
+struct LineCountInfo {
+    unsigned line;
+    unsigned count;
+};
+
+static int compareOpcodeIndicesSampling(const void* left, const void* right)
+{
+    const OpcodeSampleInfo* leftSampleInfo = reinterpret_cast<const OpcodeSampleInfo*>(left);
+    const OpcodeSampleInfo* rightSampleInfo = reinterpret_cast<const OpcodeSampleInfo*>(right);
+
+    return (leftSampleInfo->count < rightSampleInfo->count) ? 1 : (leftSampleInfo->count > rightSampleInfo->count) ? -1 : 0;
+}
+
+#if ENABLE(CODEBLOCK_SAMPLING)
+static int compareLineCountInfoSampling(const void* left, const void* right)
+{
+    const LineCountInfo* leftLineCount = reinterpret_cast<const LineCountInfo*>(left);
+    const LineCountInfo* rightLineCount = reinterpret_cast<const LineCountInfo*>(right);
+
+    return (leftLineCount->line > rightLineCount->line) ? 1 : (leftLineCount->line < rightLineCount->line) ? -1 : 0;
+}
+
+static int compareScriptSampleRecords(const void* left, const void* right)
+{
+    const ScriptSampleRecord* const leftValue = *static_cast<const ScriptSampleRecord* const *>(left);
+    const ScriptSampleRecord* const rightValue = *static_cast<const ScriptSampleRecord* const *>(right);
+
+    return (leftValue->m_sampleCount < rightValue->m_sampleCount) ? 1 : (leftValue->m_sampleCount > rightValue->m_sampleCount) ? -1 : 0;
+}
+#endif
+
+void SamplingTool::dump(ExecState* exec)
+{
+    // Tidies up SunSpider output by removing short scripts - such a small number of samples would likely not be useful anyhow.
+    if (m_sampleCount < 10)
+        return;
+    
+    // (1) Build and sort 'opcodeSampleInfo' array.
+
+    OpcodeSampleInfo opcodeSampleInfo[numOpcodeIDs];
+    for (int i = 0; i < numOpcodeIDs; ++i) {
+        opcodeSampleInfo[i].opcode = static_cast<OpcodeID>(i);
+        opcodeSampleInfo[i].count = m_opcodeSamples[i];
+        opcodeSampleInfo[i].countInCTIFunctions = m_opcodeSamplesInCTIFunctions[i];
+    }
+
+    qsort(opcodeSampleInfo, numOpcodeIDs, sizeof(OpcodeSampleInfo), compareOpcodeIndicesSampling);
+
+    // (2) Print Opcode sampling results.
+
+    printf("\nBytecode samples [*]\n");
+    printf("                             sample   %% of       %% of     |   cti     cti %%\n");
+    printf("opcode                       count     VM        total    |  count   of self\n");
+    printf("-------------------------------------------------------   |  ----------------\n");
+
+    for (int i = 0; i < numOpcodeIDs; ++i) {
+        long long count = opcodeSampleInfo[i].count;
+        if (!count)
+            continue;
+
+        OpcodeID opcodeID = opcodeSampleInfo[i].opcode;
+        
+        const char* opcodeName = opcodeNames[opcodeID];
+        const char* opcodePadding = padOpcodeName(opcodeID, 28);
+        double percentOfVM = (static_cast<double>(count) * 100) / m_opcodeSampleCount;
+        double percentOfTotal = (static_cast<double>(count) * 100) / m_sampleCount;
+        long long countInCTIFunctions = opcodeSampleInfo[i].countInCTIFunctions;
+        double percentInCTIFunctions = (static_cast<double>(countInCTIFunctions) * 100) / count;
+        fprintf(stdout, "%s:%s%-6lld %.3f%%\t%.3f%%\t  |   %-6lld %.3f%%\n", opcodeName, opcodePadding, count, percentOfVM, percentOfTotal, countInCTIFunctions, percentInCTIFunctions);
+    }
+    
+    printf("\n[*] Samples inside host code are not charged to any Bytecode.\n\n");
+    printf("\tSamples inside VM:\t\t%lld / %lld (%.3f%%)\n", m_opcodeSampleCount, m_sampleCount, (static_cast<double>(m_opcodeSampleCount) * 100) / m_sampleCount);
+    printf("\tSamples inside host code:\t%lld / %lld (%.3f%%)\n\n", m_sampleCount - m_opcodeSampleCount, m_sampleCount, (static_cast<double>(m_sampleCount - m_opcodeSampleCount) * 100) / m_sampleCount);
+    printf("\tsample count:\tsamples inside this opcode\n");
+    printf("\t%% of VM:\tsample count / all opcode samples\n");
+    printf("\t%% of total:\tsample count / all samples\n");
+    printf("\t--------------\n");
+    printf("\tcti count:\tsamples inside a CTI function called by this opcode\n");
+    printf("\tcti %% of self:\tcti count / sample count\n");
+    
+#if ENABLE(CODEBLOCK_SAMPLING)
+
+    // (3) Build and sort 'codeBlockSamples' array.
+
+    int scopeCount = m_scopeSampleMap->size();
+    Vector<ScriptSampleRecord*> codeBlockSamples(scopeCount);
+    ScriptSampleRecordMap::iterator iter = m_scopeSampleMap->begin();
+    for (int i = 0; i < scopeCount; ++i, ++iter)
+        codeBlockSamples[i] = iter->second;
+
+    qsort(codeBlockSamples.begin(), scopeCount, sizeof(ScriptSampleRecord*), compareScriptSampleRecords);
+
+    // (4) Print data from 'codeBlockSamples' array.
+
+    printf("\nCodeBlock samples\n\n"); 
+
+    for (int i = 0; i < scopeCount; ++i) {
+        ScriptSampleRecord* record = codeBlockSamples[i];
+        CodeBlock* codeBlock = record->m_codeBlock;
+
+        double blockPercent = (record->m_sampleCount * 100.0) / m_sampleCount;
+
+        if (blockPercent >= 1) {
+            //Instruction* code = codeBlock->instructions().begin();
+            printf("#%d: %s:%d: %d / %lld (%.3f%%)\n", i + 1, record->m_executable->sourceURL().utf8().data(), codeBlock->lineNumberForBytecodeOffset(0), record->m_sampleCount, m_sampleCount, blockPercent);
+            if (i < 10) {
+                HashMap<unsigned,unsigned> lineCounts;
+                codeBlock->dump(exec);
+
+                printf("    Opcode and line number samples [*]\n\n");
+                for (unsigned op = 0; op < record->m_size; ++op) {
+                    int count = record->m_samples[op];
+                    if (count) {
+                        printf("    [% 4d] has sample count: % 4d\n", op, count);
+                        unsigned line = codeBlock->lineNumberForBytecodeOffset(op);
+                        lineCounts.set(line, (lineCounts.contains(line) ? lineCounts.get(line) : 0) + count);
+                    }
+                }
+                printf("\n");
+
+                int linesCount = lineCounts.size();
+                Vector<LineCountInfo> lineCountInfo(linesCount);
+                int lineno = 0;
+                for (HashMap<unsigned,unsigned>::iterator iter = lineCounts.begin(); iter != lineCounts.end(); ++iter, ++lineno) {
+                    lineCountInfo[lineno].line = iter->first;
+                    lineCountInfo[lineno].count = iter->second;
+                }
+
+                qsort(lineCountInfo.begin(), linesCount, sizeof(LineCountInfo), compareLineCountInfoSampling);
+
+                for (lineno = 0; lineno < linesCount; ++lineno) {
+                    printf("    Line #%d has sample count %d.\n", lineCountInfo[lineno].line, lineCountInfo[lineno].count);
+                }
+                printf("\n");
+                printf("    [*] Samples inside host code are charged to the calling Bytecode.\n");
+                printf("        Samples on a call / return boundary are not charged to a specific opcode or line.\n\n");
+                printf("            Samples on a call / return boundary: %d / %d (%.3f%%)\n\n", record->m_sampleCount - record->m_opcodeSampleCount, record->m_sampleCount, (static_cast<double>(record->m_sampleCount - record->m_opcodeSampleCount) * 100) / record->m_sampleCount);
+            }
+        }
+    }
+#else
+    UNUSED_PARAM(exec);
+#endif
+}
+
+#else
+
+void SamplingTool::dump(ExecState*)
+{
+}
+
+#endif
+
+void AbstractSamplingCounter::dump()
+{
+#if ENABLE(SAMPLING_COUNTERS)
+    if (s_abstractSamplingCounterChain != &s_abstractSamplingCounterChainEnd) {
+        printf("\nSampling Counter Values:\n");
+        for (AbstractSamplingCounter* currCounter = s_abstractSamplingCounterChain; (currCounter != &s_abstractSamplingCounterChainEnd); currCounter = currCounter->m_next)
+            printf("\t%s\t: %lld\n", currCounter->m_name, currCounter->m_counter);
+        printf("\n\n");
+    }
+    s_completed = true;
+#endif
+}
+
+AbstractSamplingCounter AbstractSamplingCounter::s_abstractSamplingCounterChainEnd;
+AbstractSamplingCounter* AbstractSamplingCounter::s_abstractSamplingCounterChain = &s_abstractSamplingCounterChainEnd;
+bool AbstractSamplingCounter::s_completed = false;
+
+} // namespace JSC
diff --git a/Source/JavaScriptCore/bytecode/SamplingTool.h b/Source/JavaScriptCore/bytecode/SamplingTool.h
new file mode 100644
index 0000000..8e3ed9e
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/SamplingTool.h
@@ -0,0 +1,414 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SamplingTool_h
+#define SamplingTool_h
+
+#include <wtf/Assertions.h>
+#include <wtf/HashMap.h>
+#include <wtf/Threading.h>
+
+#include "Nodes.h"
+#include "Opcode.h"
+
+namespace JSC {
+
+    class ScriptExecutable;
+
+    class SamplingFlags {
+        friend class JIT;
+    public:
+        static void start();
+        static void stop();
+
+#if ENABLE(SAMPLING_FLAGS)
+        static void setFlag(unsigned flag)
+        {
+            ASSERT(flag >= 1);
+            ASSERT(flag <= 32);
+            s_flags |= 1u << (flag - 1);
+        }
+
+        static void clearFlag(unsigned flag)
+        {
+            ASSERT(flag >= 1);
+            ASSERT(flag <= 32);
+            s_flags &= ~(1u << (flag - 1));
+        }
+
+        static void sample();
+
+        class ScopedFlag {
+        public:
+            ScopedFlag(int flag)
+                : m_flag(flag)
+            {
+                setFlag(flag);
+            }
+
+            ~ScopedFlag()
+            {
+                clearFlag(m_flag);
+            }
+
+        private:
+            int m_flag;
+        };
+    
+#endif
+    private:
+        static uint32_t s_flags;
+#if ENABLE(SAMPLING_FLAGS)
+        static uint64_t s_flagCounts[33];
+#endif
+    };
+
+    class CodeBlock;
+    class ExecState;
+    class Interpreter;
+    class ScopeNode;
+    struct Instruction;
+
+    struct ScriptSampleRecord {
+        ScriptSampleRecord(ScriptExecutable* executable)
+            : m_executable(executable)
+            , m_codeBlock(0)
+            , m_sampleCount(0)
+            , m_opcodeSampleCount(0)
+            , m_samples(0)
+            , m_size(0)
+        {
+        }
+        
+        ~ScriptSampleRecord()
+        {
+            if (m_samples)
+                free(m_samples);
+        }
+        
+        void sample(CodeBlock*, Instruction*);
+
+        RefPtr<ScriptExecutable> m_executable;
+        CodeBlock* m_codeBlock;
+        int m_sampleCount;
+        int m_opcodeSampleCount;
+        int* m_samples;
+        unsigned m_size;
+    };
+
+    typedef WTF::HashMap<ScriptExecutable*, ScriptSampleRecord*> ScriptSampleRecordMap;
+
+    class SamplingThread {
+    public:
+        // Sampling thread state.
+        static bool s_running;
+        static unsigned s_hertz;
+        static ThreadIdentifier s_samplingThread;
+
+        static void start(unsigned hertz=10000);
+        static void stop();
+
+        static void* threadStartFunc(void*);
+    };
+
+    class SamplingTool {
+    public:
+        friend struct CallRecord;
+        friend class HostCallRecord;
+        
+#if ENABLE(OPCODE_SAMPLING)
+        class CallRecord : public Noncopyable {
+        public:
+            CallRecord(SamplingTool* samplingTool)
+                : m_samplingTool(samplingTool)
+                , m_savedSample(samplingTool->m_sample)
+                , m_savedCodeBlock(samplingTool->m_codeBlock)
+            {
+            }
+
+            ~CallRecord()
+            {
+                m_samplingTool->m_sample = m_savedSample;
+                m_samplingTool->m_codeBlock = m_savedCodeBlock;
+            }
+
+        private:
+            SamplingTool* m_samplingTool;
+            intptr_t m_savedSample;
+            CodeBlock* m_savedCodeBlock;
+        };
+        
+        class HostCallRecord : public CallRecord {
+        public:
+            HostCallRecord(SamplingTool* samplingTool)
+                : CallRecord(samplingTool)
+            {
+                samplingTool->m_sample |= 0x1;
+            }
+        };
+#else
+        class CallRecord : public Noncopyable {
+        public:
+            CallRecord(SamplingTool*)
+            {
+            }
+        };
+
+        class HostCallRecord : public CallRecord {
+        public:
+            HostCallRecord(SamplingTool* samplingTool)
+                : CallRecord(samplingTool)
+            {
+            }
+        };
+#endif        
+
+        SamplingTool(Interpreter* interpreter)
+            : m_interpreter(interpreter)
+            , m_codeBlock(0)
+            , m_sample(0)
+            , m_sampleCount(0)
+            , m_opcodeSampleCount(0)
+#if ENABLE(CODEBLOCK_SAMPLING)
+            , m_scopeSampleMap(new ScriptSampleRecordMap())
+#endif
+        {
+            memset(m_opcodeSamples, 0, sizeof(m_opcodeSamples));
+            memset(m_opcodeSamplesInCTIFunctions, 0, sizeof(m_opcodeSamplesInCTIFunctions));
+        }
+
+        ~SamplingTool()
+        {
+#if ENABLE(CODEBLOCK_SAMPLING)
+            deleteAllValues(*m_scopeSampleMap);
+#endif
+        }
+
+        void setup();
+        void dump(ExecState*);
+
+        void notifyOfScope(ScriptExecutable* scope);
+
+        void sample(CodeBlock* codeBlock, Instruction* vPC)
+        {
+            ASSERT(!(reinterpret_cast<intptr_t>(vPC) & 0x3));
+            m_codeBlock = codeBlock;
+            m_sample = reinterpret_cast<intptr_t>(vPC);
+        }
+
+        CodeBlock** codeBlockSlot() { return &m_codeBlock; }
+        intptr_t* sampleSlot() { return &m_sample; }
+
+        void* encodeSample(Instruction* vPC, bool inCTIFunction = false, bool inHostFunction = false)
+        {
+            ASSERT(!(reinterpret_cast<intptr_t>(vPC) & 0x3));
+            return reinterpret_cast<void*>(reinterpret_cast<intptr_t>(vPC) | (static_cast<intptr_t>(inCTIFunction) << 1) | static_cast<intptr_t>(inHostFunction));
+        }
+
+        static void sample();
+
+    private:
+        class Sample {
+        public:
+            Sample(volatile intptr_t sample, CodeBlock* volatile codeBlock)
+                : m_sample(sample)
+                , m_codeBlock(codeBlock)
+            {
+            }
+            
+            bool isNull() { return !m_sample; }
+            CodeBlock* codeBlock() { return m_codeBlock; }
+            Instruction* vPC() { return reinterpret_cast<Instruction*>(m_sample & ~0x3); }
+            bool inHostFunction() { return m_sample & 0x1; }
+            bool inCTIFunction() { return m_sample & 0x2; }
+
+        private:
+            intptr_t m_sample;
+            CodeBlock* m_codeBlock;
+        };
+
+        void doRun();
+        static SamplingTool* s_samplingTool;
+        
+        Interpreter* m_interpreter;
+        
+        // State tracked by the main thread, used by the sampling thread.
+        CodeBlock* m_codeBlock;
+        intptr_t m_sample;
+
+        // Gathered sample data.
+        long long m_sampleCount;
+        long long m_opcodeSampleCount;
+        unsigned m_opcodeSamples[numOpcodeIDs];
+        unsigned m_opcodeSamplesInCTIFunctions[numOpcodeIDs];
+        
+#if ENABLE(CODEBLOCK_SAMPLING)
+        Mutex m_scriptSampleMapMutex;
+        OwnPtr<ScriptSampleRecordMap> m_scopeSampleMap;
+#endif
+    };
+
+    // AbstractSamplingCounter:
+    //
+    // Implements a named set of counters, printed on exit if ENABLE(SAMPLING_COUNTERS).
+    // See subclasses below, SamplingCounter, GlobalSamplingCounter and DeletableSamplingCounter.
+    class AbstractSamplingCounter {
+        friend class JIT;
+        friend class DeletableSamplingCounter;
+    public:
+        void count(uint32_t count = 1)
+        {
+            m_counter += count;
+        }
+
+        static void dump();
+
+    protected:
+        // Effectively the contructor, however called lazily in the case of GlobalSamplingCounter.
+        void init(const char* name)
+        {
+            m_counter = 0;
+            m_name = name;
+
+            // Set m_next to point to the head of the chain, and inform whatever is
+            // currently at the head that this node will now hold the pointer to it.
+            m_next = s_abstractSamplingCounterChain;
+            s_abstractSamplingCounterChain->m_referer = &m_next;
+            // Add this node to the head of the list.
+            s_abstractSamplingCounterChain = this;
+            m_referer = &s_abstractSamplingCounterChain;
+        }
+
+        int64_t m_counter;
+        const char* m_name;
+        AbstractSamplingCounter* m_next;
+        // This is a pointer to the pointer to this node in the chain; used to
+        // allow fast linked list deletion.
+        AbstractSamplingCounter** m_referer;
+        // Null object used to detect end of static chain.
+        static AbstractSamplingCounter s_abstractSamplingCounterChainEnd;
+        static AbstractSamplingCounter* s_abstractSamplingCounterChain;
+        static bool s_completed;
+    };
+
+#if ENABLE(SAMPLING_COUNTERS)
+    // SamplingCounter:
+    //
+    // This class is suitable and (hopefully!) convenient for cases where a counter is
+    // required within the scope of a single function.  It can be instantiated as a
+    // static variable since it contains a constructor but not a destructor (static
+    // variables in WebKit cannot have destructors).
+    //
+    // For example:
+    //
+    // void someFunction()
+    // {
+    //     static SamplingCounter countMe("This is my counter.  There are many like it, but this one is mine.");
+    //     countMe.count();
+    //     // ...
+    // }
+    //
+    class SamplingCounter : public AbstractSamplingCounter {
+    public:
+        SamplingCounter(const char* name) { init(name); }
+    };
+
+    // GlobalSamplingCounter:
+    //
+    // This class is suitable for use where a counter is to be declared globally,
+    // since it contains neither a constructor nor destructor.  Instead, ensure
+    // that 'name()' is called to provide the counter with a name (and also to
+    // allow it to be printed out on exit).
+    //
+    // GlobalSamplingCounter globalCounter;
+    //
+    // void firstFunction()
+    // {
+    //     // Put this within a function that is definitely called!
+    //     // (Or alternatively alongside all calls to 'count()').
+    //     globalCounter.name("I Name You Destroyer.");
+    //     globalCounter.count();
+    //     // ...
+    // }
+    //
+    // void secondFunction()
+    // {
+    //     globalCounter.count();
+    //     // ...
+    // }
+    //
+    class GlobalSamplingCounter : public AbstractSamplingCounter {
+    public:
+        void name(const char* name)
+        {
+            // Global objects should be mapped in zero filled memory, so this should
+            // be a safe (albeit not necessarily threadsafe) check for 'first call'.
+            if (!m_next)
+                init(name);
+        }
+    };
+
+    // DeletableSamplingCounter:
+    //
+    // The above classes (SamplingCounter, GlobalSamplingCounter), are intended for
+    // use within a global or static scope, and as such cannot have a destructor.
+    // This means there is no convenient way for them to remove themselves from the
+    // static list of counters, and should an instance of either class be freed
+    // before 'dump()' has walked over the list it will potentially walk over an
+    // invalid pointer.
+    //
+    // This class is intended for use where the counter may possibly be deleted before
+    // the program exits.  Should this occur, the counter will print it's value to
+    // stderr, and remove itself from the static list.  Example:
+    //
+    // DeletableSamplingCounter* counter = new DeletableSamplingCounter("The Counter With No Name");
+    // counter->count();
+    // delete counter;
+    //
+    class DeletableSamplingCounter : public AbstractSamplingCounter {
+    public:
+        DeletableSamplingCounter(const char* name) { init(name); }
+
+        ~DeletableSamplingCounter()
+        {
+            if (!s_completed)
+                fprintf(stderr, "DeletableSamplingCounter \"%s\" deleted early (with count %lld)\n", m_name, m_counter);
+            // Our m_referer pointer should know where the pointer to this node is,
+            // and m_next should know that this node is the previous node in the list.
+            ASSERT(*m_referer == this);
+            ASSERT(m_next->m_referer == &m_next);
+            // Remove this node from the list, and inform m_next that we have done so.
+            m_next->m_referer = m_referer;
+            *m_referer = m_next;
+        }
+    };
+#endif
+
+} // namespace JSC
+
+#endif // SamplingTool_h
diff --git a/Source/JavaScriptCore/bytecode/StructureStubInfo.cpp b/Source/JavaScriptCore/bytecode/StructureStubInfo.cpp
new file mode 100644
index 0000000..018d832
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/StructureStubInfo.cpp
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "config.h"
+#include "StructureStubInfo.h"
+
+namespace JSC {
+
+#if ENABLE(JIT)
+void StructureStubInfo::deref()
+{
+    switch (accessType) {
+    case access_get_by_id_self:
+        u.getByIdSelf.baseObjectStructure->deref();
+        return;
+    case access_get_by_id_proto:
+        u.getByIdProto.baseObjectStructure->deref();
+        u.getByIdProto.prototypeStructure->deref();
+        return;
+    case access_get_by_id_chain:
+        u.getByIdChain.baseObjectStructure->deref();
+        u.getByIdChain.chain->deref();
+        return;
+    case access_get_by_id_self_list: {
+        PolymorphicAccessStructureList* polymorphicStructures = u.getByIdSelfList.structureList;
+        polymorphicStructures->derefStructures(u.getByIdSelfList.listSize);
+        delete polymorphicStructures;
+        return;
+    }
+    case access_get_by_id_proto_list: {
+        PolymorphicAccessStructureList* polymorphicStructures = u.getByIdProtoList.structureList;
+        polymorphicStructures->derefStructures(u.getByIdProtoList.listSize);
+        delete polymorphicStructures;
+        return;
+    }
+    case access_put_by_id_transition:
+        u.putByIdTransition.previousStructure->deref();
+        u.putByIdTransition.structure->deref();
+        u.putByIdTransition.chain->deref();
+        return;
+    case access_put_by_id_replace:
+        u.putByIdReplace.baseObjectStructure->deref();
+        return;
+    case access_get_by_id:
+    case access_put_by_id:
+    case access_get_by_id_generic:
+    case access_put_by_id_generic:
+    case access_get_array_length:
+    case access_get_string_length:
+        // These instructions don't ref their Structures.
+        return;
+    default:
+        ASSERT_NOT_REACHED();
+    }
+}
+#endif
+
+} // namespace JSC
diff --git a/Source/JavaScriptCore/bytecode/StructureStubInfo.h b/Source/JavaScriptCore/bytecode/StructureStubInfo.h
new file mode 100644
index 0000000..8e2c489
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/StructureStubInfo.h
@@ -0,0 +1,185 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#ifndef StructureStubInfo_h
+#define StructureStubInfo_h
+
+#if ENABLE(JIT)
+
+#include "Instruction.h"
+#include "MacroAssembler.h"
+#include "Opcode.h"
+#include "Structure.h"
+
+namespace JSC {
+
+    enum AccessType {
+        access_get_by_id_self,
+        access_get_by_id_proto,
+        access_get_by_id_chain,
+        access_get_by_id_self_list,
+        access_get_by_id_proto_list,
+        access_put_by_id_transition,
+        access_put_by_id_replace,
+        access_get_by_id,
+        access_put_by_id,
+        access_get_by_id_generic,
+        access_put_by_id_generic,
+        access_get_array_length,
+        access_get_string_length,
+    };
+
+    struct StructureStubInfo {
+        StructureStubInfo(AccessType accessType)
+            : accessType(accessType)
+            , seen(false)
+        {
+        }
+
+        void initGetByIdSelf(Structure* baseObjectStructure)
+        {
+            accessType = access_get_by_id_self;
+
+            u.getByIdSelf.baseObjectStructure = baseObjectStructure;
+            baseObjectStructure->ref();
+        }
+
+        void initGetByIdProto(Structure* baseObjectStructure, Structure* prototypeStructure)
+        {
+            accessType = access_get_by_id_proto;
+
+            u.getByIdProto.baseObjectStructure = baseObjectStructure;
+            baseObjectStructure->ref();
+
+            u.getByIdProto.prototypeStructure = prototypeStructure;
+            prototypeStructure->ref();
+        }
+
+        void initGetByIdChain(Structure* baseObjectStructure, StructureChain* chain)
+        {
+            accessType = access_get_by_id_chain;
+
+            u.getByIdChain.baseObjectStructure = baseObjectStructure;
+            baseObjectStructure->ref();
+
+            u.getByIdChain.chain = chain;
+            chain->ref();
+        }
+
+        void initGetByIdSelfList(PolymorphicAccessStructureList* structureList, int listSize)
+        {
+            accessType = access_get_by_id_self_list;
+
+            u.getByIdProtoList.structureList = structureList;
+            u.getByIdProtoList.listSize = listSize;
+        }
+
+        void initGetByIdProtoList(PolymorphicAccessStructureList* structureList, int listSize)
+        {
+            accessType = access_get_by_id_proto_list;
+
+            u.getByIdProtoList.structureList = structureList;
+            u.getByIdProtoList.listSize = listSize;
+        }
+
+        // PutById*
+
+        void initPutByIdTransition(Structure* previousStructure, Structure* structure, StructureChain* chain)
+        {
+            accessType = access_put_by_id_transition;
+
+            u.putByIdTransition.previousStructure = previousStructure;
+            previousStructure->ref();
+
+            u.putByIdTransition.structure = structure;
+            structure->ref();
+
+            u.putByIdTransition.chain = chain;
+            chain->ref();
+        }
+
+        void initPutByIdReplace(Structure* baseObjectStructure)
+        {
+            accessType = access_put_by_id_replace;
+    
+            u.putByIdReplace.baseObjectStructure = baseObjectStructure;
+            baseObjectStructure->ref();
+        }
+
+        void deref();
+
+        bool seenOnce()
+        {
+            return seen;
+        }
+
+        void setSeen()
+        {
+            seen = true;
+        }
+
+        int accessType : 31;
+        int seen : 1;
+
+        union {
+            struct {
+                Structure* baseObjectStructure;
+            } getByIdSelf;
+            struct {
+                Structure* baseObjectStructure;
+                Structure* prototypeStructure;
+            } getByIdProto;
+            struct {
+                Structure* baseObjectStructure;
+                StructureChain* chain;
+            } getByIdChain;
+            struct {
+                PolymorphicAccessStructureList* structureList;
+                int listSize;
+            } getByIdSelfList;
+            struct {
+                PolymorphicAccessStructureList* structureList;
+                int listSize;
+            } getByIdProtoList;
+            struct {
+                Structure* previousStructure;
+                Structure* structure;
+                StructureChain* chain;
+            } putByIdTransition;
+            struct {
+                Structure* baseObjectStructure;
+            } putByIdReplace;
+        } u;
+
+        CodeLocationLabel stubRoutine;
+        CodeLocationCall callReturnLocation;
+        CodeLocationLabel hotPathBegin;
+    };
+
+} // namespace JSC
+
+#endif
+
+#endif // StructureStubInfo_h