Imported WebKit commit 2ea9d364d0f6efa8fa64acf19f451504c59be0e4 (http://svn.webkit.org/repository/webkit/trunk@104285)

1 files changed, 2337 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/bytecode/CodeBlock.cpp b/Source/JavaScriptCore/bytecode/CodeBlock.cpp
new file mode 100644
index 000000000..a14ce64a1
--- /dev/null
+++ b/Source/JavaScriptCore/bytecode/CodeBlock.cpp
@@ -0,0 +1,2337 @@
+/*
+ * 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 "DFGCapabilities.h"
+#include "DFGNode.h"
+#include "DFGRepatch.h"
+#include "Debugger.h"
+#include "Interpreter.h"
+#include "JIT.h"
+#include "JITStubs.h"
+#include "JSActivation.h"
+#include "JSFunction.h"
+#include "JSStaticScopeObject.h"
+#include "JSValue.h"
+#include "RepatchBuffer.h"
+#include "UStringConcatenate.h"
+#include <stdio.h>
+#include <wtf/StringExtras.h>
+
+#if ENABLE(DFG_JIT)
+#include "DFGOperations.h"
+#endif
+
+#define DUMP_CODE_BLOCK_STATISTICS 0
+
+namespace JSC {
+
+#if ENABLE(DFG_JIT)
+using namespace DFG;
+#endif
+
+#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.description();
+}
+
+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_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_normal:
+    case access_put_by_id_transition_direct:
+        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_unset:
+        printf("  [%4d] %s\n", instructionOffset, "unset");
+        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 - 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 - 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) {
+        printf("No instructions available.\n");
+        return;
+    }
+
+    size_t instructionCount = 0;
+
+    for (size_t i = 0; i < instructions().size(); i += opcodeLengths[exec->interpreter()->getOpcodeID(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>(instructions().size() * sizeof(Instruction)),
+        this, m_numParameters, m_numCalleeRegisters);
+
+    Vector<Instruction>::const_iterator begin = instructions().begin();
+    Vector<Instruction>::const_iterator end = 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");
+        size_t i = 0;
+        do {
+            printf("   k%u = %s\n", static_cast<unsigned>(i), valueToSourceString(exec, m_constantRegisters[i].get()).utf8().data());
+            ++i;
+        } 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, 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, instructions(), i + 1, isPropertyAccess));
+             ++i;
+        } while (i < m_structureStubInfos.size());
+    }
+#endif
+#if ENABLE(INTERPRETER)
+    if (!m_globalResolveInstructions.isEmpty() || !m_propertyAccessInstructions.isEmpty())
+        printf("\nStructures:\n");
+
+    if (!m_globalResolveInstructions.isEmpty()) {
+        size_t i = 0;
+        do {
+             printStructures(&instructions()[m_globalResolveInstructions[i]]);
+             ++i;
+        } while (i < m_globalResolveInstructions.size());
+    }
+    if (!m_propertyAccessInstructions.isEmpty()) {
+        size_t i = 0;
+        do {
+            printStructures(&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_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_array_buffer: {
+            int dst = (++it)->u.operand;
+            int argv = (++it)->u.operand;
+            int argc = (++it)->u.operand;
+            printf("[%4d] new_array_buffer %s, %d, %d\n", location, registerName(exec, dst).data(), argv, argc);
+            break;
+        }
+        case op_new_regexp: {
+            int r0 = (++it)->u.operand;
+            int re0 = (++it)->u.operand;
+            printf("[%4d] new_regexp\t %s, ", location, registerName(exec, r0).data());
+            if (r0 >=0 && r0 < (int)numberOfRegExps())
+                printf("%s\n", regexpName(re0, regexp(re0)).data());
+            else
+                printf("bad_regexp(%d)\n", re0);
+            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_greater: {
+            printBinaryOp(exec, location, it, "greater");
+            break;
+        }
+        case op_greatereq: {
+            printBinaryOp(exec, location, it, "greatereq");
+            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.get());
+            ++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_resolve_with_this: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int id0 = (++it)->u.operand;
+            printf("[%4d] resolve_with_this %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_proto: {
+            printGetByIdOp(exec, location, it, "get_by_id_proto");
+            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_proto: {
+            printGetByIdOp(exec, location, it, "get_by_id_getter_proto");
+            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_proto: {
+            printGetByIdOp(exec, location, it, "get_by_id_custom_proto");
+            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_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_jgreater: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jgreater\t\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_jgreatereq: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jgreatereq\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_jngreater: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jngreater\t\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_jngreatereq: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] jngreatereq\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_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_loop_if_greater: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] loop_if_greater\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_loop_if_greatereq: {
+            int r0 = (++it)->u.operand;
+            int r1 = (++it)->u.operand;
+            int offset = (++it)->u.operand;
+            printf("[%4d] loop_if_greatereq\t %s, %s, %d(->%d)\n", location, registerName(exec, r0).data(), registerName(exec, r1).data(), offset, location + offset);
+            break;
+        }
+        case op_loop_hint: {
+            printf("[%4d] loop_hint\n", location);
+            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 callee = (++it)->u.operand;
+            int thisValue = (++it)->u.operand;
+            int arguments = (++it)->u.operand;
+            int firstFreeRegister = (++it)->u.operand;
+            printf("[%4d] call_varargs\t %s, %s, %s, %d\n", location, registerName(exec, callee).data(), registerName(exec, thisValue).data(), registerName(exec, arguments).data(), firstFreeRegister);
+            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_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(CopyParsedBlockTag, CodeBlock& other, SymbolTable* symTab)
+    : m_globalObject(other.m_globalObject)
+    , m_heap(other.m_heap)
+    , m_numCalleeRegisters(other.m_numCalleeRegisters)
+    , m_numVars(other.m_numVars)
+    , m_numCapturedVars(other.m_numCapturedVars)
+    , m_numParameters(other.m_numParameters)
+    , m_isConstructor(other.m_isConstructor)
+    , m_shouldDiscardBytecode(false)
+    , m_ownerExecutable(*other.m_globalData, other.m_ownerExecutable.get(), other.m_ownerExecutable.get())
+    , m_globalData(other.m_globalData)
+    , m_instructions(other.m_instructions)
+    , m_instructionCount(other.m_instructionCount)
+    , m_thisRegister(other.m_thisRegister)
+    , m_argumentsRegister(other.m_argumentsRegister)
+    , m_activationRegister(other.m_activationRegister)
+    , m_needsFullScopeChain(other.m_needsFullScopeChain)
+    , m_usesEval(other.m_usesEval)
+    , m_isNumericCompareFunction(other.m_isNumericCompareFunction)
+    , m_isStrictMode(other.m_isStrictMode)
+    , m_codeType(other.m_codeType)
+    , m_source(other.m_source)
+    , m_sourceOffset(other.m_sourceOffset)
+#if ENABLE(JIT)
+    , m_globalResolveInfos(other.m_globalResolveInfos)
+#endif
+#if ENABLE(VALUE_PROFILER)
+    , m_executionEntryCount(0)
+#endif
+    , m_jumpTargets(other.m_jumpTargets)
+    , m_loopTargets(other.m_loopTargets)
+    , m_identifiers(other.m_identifiers)
+    , m_constantRegisters(other.m_constantRegisters)
+    , m_functionDecls(other.m_functionDecls)
+    , m_functionExprs(other.m_functionExprs)
+    , m_symbolTable(symTab)
+    , m_speculativeSuccessCounter(0)
+    , m_speculativeFailCounter(0)
+    , m_optimizationDelayCounter(0)
+    , m_reoptimizationRetryCounter(0)
+{
+    optimizeAfterWarmUp();
+    
+    if (other.m_rareData) {
+        createRareDataIfNecessary();
+        
+        m_rareData->m_exceptionHandlers = other.m_rareData->m_exceptionHandlers;
+        m_rareData->m_regexps = other.m_rareData->m_regexps;
+        m_rareData->m_constantBuffers = other.m_rareData->m_constantBuffers;
+        m_rareData->m_immediateSwitchJumpTables = other.m_rareData->m_immediateSwitchJumpTables;
+        m_rareData->m_characterSwitchJumpTables = other.m_rareData->m_characterSwitchJumpTables;
+        m_rareData->m_stringSwitchJumpTables = other.m_rareData->m_stringSwitchJumpTables;
+        m_rareData->m_expressionInfo = other.m_rareData->m_expressionInfo;
+        m_rareData->m_lineInfo = other.m_rareData->m_lineInfo;
+    }
+}
+
+CodeBlock::CodeBlock(ScriptExecutable* ownerExecutable, CodeType codeType, JSGlobalObject *globalObject, PassRefPtr<SourceProvider> sourceProvider, unsigned sourceOffset, SymbolTable* symTab, bool isConstructor, PassOwnPtr<CodeBlock> alternative)
+    : m_globalObject(globalObject->globalData(), ownerExecutable, globalObject)
+    , m_heap(&m_globalObject->globalData().heap)
+    , m_numCalleeRegisters(0)
+    , m_numVars(0)
+    , m_numParameters(0)
+    , m_isConstructor(isConstructor)
+    , m_shouldDiscardBytecode(false)
+    , m_ownerExecutable(globalObject->globalData(), ownerExecutable, ownerExecutable)
+    , m_globalData(0)
+    , m_instructions(adoptRef(new Instructions))
+    , m_instructionCount(0)
+    , 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)
+#if ENABLE(VALUE_PROFILER)
+    , m_executionEntryCount(0)
+#endif
+    , m_symbolTable(symTab)
+    , m_alternative(alternative)
+    , m_speculativeSuccessCounter(0)
+    , m_speculativeFailCounter(0)
+    , m_optimizationDelayCounter(0)
+    , m_reoptimizationRetryCounter(0)
+{
+    ASSERT(m_source);
+    
+    optimizeAfterWarmUp();
+
+#if DUMP_CODE_BLOCK_STATISTICS
+    liveCodeBlockSet.add(this);
+#endif
+}
+
+CodeBlock::~CodeBlock()
+{
+#if ENABLE(DFG_JIT)
+    // Remove myself from the set of DFG code blocks. Note that I may not be in this set
+    // (because I'm not a DFG code block), in which case this is a no-op anyway.
+    m_globalData->heap.m_dfgCodeBlocks.m_set.remove(this);
+#endif
+    
+#if ENABLE(VERBOSE_VALUE_PROFILE)
+    dumpValueProfiles();
+#endif
+    
+#if ENABLE(JIT)
+    // We may be destroyed before any CodeBlocks that refer to us are destroyed.
+    // Consider that two CodeBlocks become unreachable at the same time. There
+    // is no guarantee about the order in which the CodeBlocks are destroyed.
+    // So, if we don't remove incoming calls, and get destroyed before the
+    // CodeBlock(s) that have calls into us, then the CallLinkInfo vector's
+    // destructor will try to remove nodes from our (no longer valid) linked list.
+    while (m_incomingCalls.begin() != m_incomingCalls.end())
+        m_incomingCalls.begin()->remove();
+    
+    // Note that our outgoing calls will be removed from other CodeBlocks'
+    // m_incomingCalls linked lists through the execution of the ~CallLinkInfo
+    // destructors.
+
+    for (size_t size = m_structureStubInfos.size(), i = 0; i < size; ++i)
+        m_structureStubInfos[i].deref();
+#endif // ENABLE(JIT)
+
+#if DUMP_CODE_BLOCK_STATISTICS
+    liveCodeBlockSet.remove(this);
+#endif
+}
+
+void CodeBlock::visitStructures(SlotVisitor& visitor, Instruction* vPC) const
+{
+    Interpreter* interpreter = m_globalData->interpreter;
+
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_get_by_id) && vPC[4].u.structure) {
+        visitor.append(&vPC[4].u.structure);
+        return;
+    }
+
+    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)) {
+        visitor.append(&vPC[4].u.structure);
+        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)) {
+        visitor.append(&vPC[4].u.structure);
+        visitor.append(&vPC[5].u.structure);
+        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)) {
+        visitor.append(&vPC[4].u.structure);
+        visitor.append(&vPC[5].u.structureChain);
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_transition)) {
+        visitor.append(&vPC[4].u.structure);
+        visitor.append(&vPC[5].u.structure);
+        visitor.append(&vPC[6].u.structureChain);
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id) && vPC[4].u.structure) {
+        visitor.append(&vPC[4].u.structure);
+        return;
+    }
+    if (vPC[0].u.opcode == interpreter->getOpcode(op_put_by_id_replace)) {
+        visitor.append(&vPC[4].u.structure);
+        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)
+            visitor.append(&vPC[3].u.structure);
+        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 EvalCodeCache::visitAggregate(SlotVisitor& visitor)
+{
+    EvalCacheMap::iterator end = m_cacheMap.end();
+    for (EvalCacheMap::iterator ptr = m_cacheMap.begin(); ptr != end; ++ptr)
+        visitor.append(&ptr->second);
+}
+
+void CodeBlock::visitAggregate(SlotVisitor& visitor)
+{
+    if (!!m_alternative)
+        m_alternative->visitAggregate(visitor);
+
+    // There are three things that may use unconditional finalizers: lazy bytecode freeing,
+    // inline cache clearing, and jettisoning. The probability of us wanting to do at
+    // least one of those things is probably quite close to 1. So we add one no matter what
+    // and when it runs, it figures out whether it has any work to do.
+    visitor.addUnconditionalFinalizer(this);
+    
+    if (shouldImmediatelyAssumeLivenessDuringScan()) {
+        // This code block is live, so scan all references strongly and return.
+        stronglyVisitStrongReferences(visitor);
+        stronglyVisitWeakReferences(visitor);
+        return;
+    }
+    
+#if ENABLE(DFG_JIT)
+    // We get here if we're live in the sense that our owner executable is live,
+    // but we're not yet live for sure in another sense: we may yet decide that this
+    // code block should be jettisoned based on its outgoing weak references being
+    // stale. Set a flag to indicate that we're still assuming that we're dead, and
+    // perform one round of determining if we're live. The GC may determine, based on
+    // either us marking additional objects, or by other objects being marked for
+    // other reasons, that this iteration should run again; it will notify us of this
+    // decision by calling harvestWeakReferences().
+    
+    m_dfgData->livenessHasBeenProved = false;
+    m_dfgData->allTransitionsHaveBeenMarked = false;
+    
+    performTracingFixpointIteration(visitor);
+
+    // GC doesn't have enough information yet for us to decide whether to keep our DFG
+    // data, so we need to register a handler to run again at the end of GC, when more
+    // information is available.
+    if (!(m_dfgData->livenessHasBeenProved && m_dfgData->allTransitionsHaveBeenMarked))
+        visitor.addWeakReferenceHarvester(this);
+    
+#else // ENABLE(DFG_JIT)
+    ASSERT_NOT_REACHED();
+#endif // ENABLE(DFG_JIT)
+}
+
+void CodeBlock::performTracingFixpointIteration(SlotVisitor& visitor)
+{
+    UNUSED_PARAM(visitor);
+    
+#if ENABLE(DFG_JIT)
+    // Evaluate our weak reference transitions, if there are still some to evaluate.
+    if (!m_dfgData->allTransitionsHaveBeenMarked) {
+        bool allAreMarkedSoFar = true;
+        for (unsigned i = 0; i < m_dfgData->transitions.size(); ++i) {
+            if ((!m_dfgData->transitions[i].m_codeOrigin
+                 || Heap::isMarked(m_dfgData->transitions[i].m_codeOrigin.get()))
+                && Heap::isMarked(m_dfgData->transitions[i].m_from.get())) {
+                // If the following three things are live, then the target of the
+                // transition is also live:
+                // - This code block. We know it's live already because otherwise
+                //   we wouldn't be scanning ourselves.
+                // - The code origin of the transition. Transitions may arise from
+                //   code that was inlined. They are not relevant if the user's
+                //   object that is required for the inlinee to run is no longer
+                //   live.
+                // - The source of the transition. The transition checks if some
+                //   heap location holds the source, and if so, stores the target.
+                //   Hence the source must be live for the transition to be live.
+                visitor.append(&m_dfgData->transitions[i].m_to);
+            } else
+                allAreMarkedSoFar = false;
+        }
+        
+        if (allAreMarkedSoFar)
+            m_dfgData->allTransitionsHaveBeenMarked = true;
+    }
+    
+    // Check if we have any remaining work to do.
+    if (m_dfgData->livenessHasBeenProved)
+        return;
+    
+    // Now check all of our weak references. If all of them are live, then we
+    // have proved liveness and so we scan our strong references. If at end of
+    // GC we still have not proved liveness, then this code block is toast.
+    bool allAreLiveSoFar = true;
+    for (unsigned i = 0; i < m_dfgData->weakReferences.size(); ++i) {
+        if (!Heap::isMarked(m_dfgData->weakReferences[i].get())) {
+            allAreLiveSoFar = false;
+            break;
+        }
+    }
+    
+    // If some weak references are dead, then this fixpoint iteration was
+    // unsuccessful.
+    if (!allAreLiveSoFar)
+        return;
+    
+    // All weak references are live. Record this information so we don't
+    // come back here again, and scan the strong references.
+    m_dfgData->livenessHasBeenProved = true;
+    stronglyVisitStrongReferences(visitor);
+#endif // ENABLE(DFG_JIT)
+}
+
+void CodeBlock::visitWeakReferences(SlotVisitor& visitor)
+{
+    performTracingFixpointIteration(visitor);
+}
+
+void CodeBlock::finalizeUnconditionally()
+{
+#if ENABLE(JIT)
+#if ENABLE(JIT_VERBOSE_OSR)
+    static const bool verboseUnlinking = true;
+#else
+    static const bool verboseUnlinking = false;
+#endif
+#endif
+    
+#if ENABLE(DFG_JIT)
+    // Check if we're not live. If we are, then jettison.
+    if (!(shouldImmediatelyAssumeLivenessDuringScan() || m_dfgData->livenessHasBeenProved)) {
+        if (verboseUnlinking)
+            printf("Code block %p has dead weak references, jettisoning during GC.\n", this);
+
+        // Make sure that the baseline JIT knows that it should re-warm-up before
+        // optimizing.
+        alternative()->optimizeAfterWarmUp();
+        
+        jettison();
+        return;
+    }
+#endif // ENABLE(DFG_JIT)
+    
+#if ENABLE(JIT)
+    // Handle inline caches.
+    if (!!getJITCode()) {
+        RepatchBuffer repatchBuffer(this);
+        for (unsigned i = 0; i < numberOfCallLinkInfos(); ++i) {
+            if (callLinkInfo(i).isLinked() && !Heap::isMarked(callLinkInfo(i).callee.get())) {
+                if (verboseUnlinking)
+                    printf("Clearing call from %p.\n", this);
+                callLinkInfo(i).unlink(*m_globalData, repatchBuffer);
+            }
+            if (!!callLinkInfo(i).lastSeenCallee
+                && !Heap::isMarked(callLinkInfo(i).lastSeenCallee.get()))
+                callLinkInfo(i).lastSeenCallee.clear();
+        }
+        for (size_t size = m_globalResolveInfos.size(), i = 0; i < size; ++i) {
+            if (m_globalResolveInfos[i].structure && !Heap::isMarked(m_globalResolveInfos[i].structure.get())) {
+                if (verboseUnlinking)
+                    printf("Clearing resolve info in %p.\n", this);
+                m_globalResolveInfos[i].structure.clear();
+            }
+        }
+
+        for (size_t size = m_structureStubInfos.size(), i = 0; i < size; ++i) {
+            StructureStubInfo& stubInfo = m_structureStubInfos[i];
+            
+            AccessType accessType = static_cast<AccessType>(stubInfo.accessType);
+            
+            if (stubInfo.visitWeakReferences())
+                continue;
+            
+            if (verboseUnlinking)
+                printf("Clearing structure cache (kind %d) in %p.\n", stubInfo.accessType, this);
+            
+            if (isGetByIdAccess(accessType)) {
+                if (getJITCode().jitType() == JITCode::DFGJIT)
+                    DFG::dfgResetGetByID(repatchBuffer, stubInfo);
+                else
+                    JIT::resetPatchGetById(repatchBuffer, &stubInfo);
+            } else {
+                ASSERT(isPutByIdAccess(accessType));
+                if (getJITCode().jitType() == JITCode::DFGJIT)
+                    DFG::dfgResetPutByID(repatchBuffer, stubInfo);
+                else 
+                    JIT::resetPatchPutById(repatchBuffer, &stubInfo);
+            }
+            
+            stubInfo.reset();
+        }
+
+        for (size_t size = m_methodCallLinkInfos.size(), i = 0; i < size; ++i) {
+            if (!m_methodCallLinkInfos[i].cachedStructure)
+                continue;
+            
+            ASSERT(m_methodCallLinkInfos[i].seenOnce());
+            ASSERT(!!m_methodCallLinkInfos[i].cachedPrototypeStructure);
+
+            if (!Heap::isMarked(m_methodCallLinkInfos[i].cachedStructure.get())
+                || !Heap::isMarked(m_methodCallLinkInfos[i].cachedPrototypeStructure.get())
+                || !Heap::isMarked(m_methodCallLinkInfos[i].cachedFunction.get())
+                || !Heap::isMarked(m_methodCallLinkInfos[i].cachedPrototype.get())) {
+                if (verboseUnlinking)
+                    printf("Clearing method call in %p.\n", this);
+                m_methodCallLinkInfos[i].reset(repatchBuffer, getJITType());
+
+                StructureStubInfo& stubInfo = getStubInfo(m_methodCallLinkInfos[i].bytecodeIndex);
+
+                AccessType accessType = static_cast<AccessType>(stubInfo.accessType);
+
+                if (accessType != access_unset) {
+                    ASSERT(isGetByIdAccess(accessType));
+                    if (getJITCode().jitType() == JITCode::DFGJIT)
+                        DFG::dfgResetGetByID(repatchBuffer, stubInfo);
+                    else
+                        JIT::resetPatchGetById(repatchBuffer, &stubInfo);
+                    stubInfo.reset();
+                }
+            }
+        }
+    }
+#endif
+
+    // Handle the bytecode discarding chore.
+    if (m_shouldDiscardBytecode) {
+        discardBytecode();
+        m_shouldDiscardBytecode = false;
+    }
+}
+
+void CodeBlock::stronglyVisitStrongReferences(SlotVisitor& visitor)
+{
+    visitor.append(&m_globalObject);
+    visitor.append(&m_ownerExecutable);
+    if (m_rareData) {
+        m_rareData->m_evalCodeCache.visitAggregate(visitor);
+        size_t regExpCount = m_rareData->m_regexps.size();
+        WriteBarrier<RegExp>* regexps = m_rareData->m_regexps.data();
+        for (size_t i = 0; i < regExpCount; i++)
+            visitor.append(regexps + i);
+    }
+    visitor.appendValues(m_constantRegisters.data(), m_constantRegisters.size());
+    for (size_t i = 0; i < m_functionExprs.size(); ++i)
+        visitor.append(&m_functionExprs[i]);
+    for (size_t i = 0; i < m_functionDecls.size(); ++i)
+        visitor.append(&m_functionDecls[i]);
+#if ENABLE(INTERPRETER)
+    for (size_t size = m_propertyAccessInstructions.size(), i = 0; i < size; ++i)
+        visitStructures(visitor, &instructions()[m_propertyAccessInstructions[i]]);
+    for (size_t size = m_globalResolveInstructions.size(), i = 0; i < size; ++i)
+        visitStructures(visitor, &instructions()[m_globalResolveInstructions[i]]);
+#endif
+
+#if ENABLE(DFG_JIT)
+    if (hasCodeOrigins()) {
+        // Make sure that executables that we have inlined don't die.
+        // FIXME: If they would have otherwise died, we should probably trigger recompilation.
+        for (size_t i = 0; i < inlineCallFrames().size(); ++i) {
+            visitor.append(&inlineCallFrames()[i].executable);
+            visitor.append(&inlineCallFrames()[i].callee);
+        }
+    }
+#endif
+
+#if ENABLE(VALUE_PROFILER)
+    for (unsigned profileIndex = 0; profileIndex < numberOfArgumentValueProfiles(); ++profileIndex)
+        valueProfileForArgument(profileIndex)->computeUpdatedPrediction();
+    for (unsigned profileIndex = 0; profileIndex < numberOfValueProfiles(); ++profileIndex)
+        valueProfile(profileIndex)->computeUpdatedPrediction();
+#endif
+}
+
+void CodeBlock::stronglyVisitWeakReferences(SlotVisitor& visitor)
+{
+    UNUSED_PARAM(visitor);
+
+#if ENABLE(DFG_JIT)
+    if (!m_dfgData)
+        return;
+
+    for (unsigned i = 0; i < m_dfgData->transitions.size(); ++i) {
+        if (!!m_dfgData->transitions[i].m_codeOrigin)
+            visitor.append(&m_dfgData->transitions[i].m_codeOrigin); // Almost certainly not necessary, since the code origin should also be a weak reference. Better to be safe, though.
+        visitor.append(&m_dfgData->transitions[i].m_from);
+        visitor.append(&m_dfgData->transitions[i].m_to);
+    }
+    
+    for (unsigned i = 0; i < m_dfgData->weakReferences.size(); ++i)
+        visitor.append(&m_dfgData->weakReferences[i]);
+#endif    
+}
+
+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()
+{
+    instructions().shrinkToFit();
+
+#if ENABLE(INTERPRETER)
+    m_propertyAccessInstructions.shrinkToFit();
+    m_globalResolveInstructions.shrinkToFit();
+#endif
+#if ENABLE(JIT)
+    m_structureStubInfos.shrinkToFit();
+    m_globalResolveInfos.shrinkToFit();
+    m_callLinkInfos.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 = JSActivation::create(callFrame->globalData(), callFrame, static_cast<FunctionExecutable*>(ownerExecutable()));
+    callFrame->uncheckedR(activationRegister()) = JSValue(activation);
+    callFrame->setScopeChain(callFrame->scopeChain()->push(activation));
+}
+    
+#if ENABLE(JIT)
+void CallLinkInfo::unlink(JSGlobalData& globalData, RepatchBuffer& repatchBuffer)
+{
+    ASSERT(isLinked());
+    
+    if (isDFG) {
+#if ENABLE(DFG_JIT)
+        repatchBuffer.relink(CodeLocationCall(callReturnLocation), callType == Construct ? operationLinkConstruct : operationLinkCall);
+#else
+        ASSERT_NOT_REACHED();
+#endif
+    } else
+        repatchBuffer.relink(CodeLocationNearCall(callReturnLocation), callType == Construct ? globalData.jitStubs->ctiVirtualConstructLink() : globalData.jitStubs->ctiVirtualCallLink());
+    hasSeenShouldRepatch = false;
+    callee.clear();
+
+    // It will be on a list if the callee has a code block.
+    if (isOnList())
+        remove();
+}
+
+void MethodCallLinkInfo::reset(RepatchBuffer& repatchBuffer, JITCode::JITType jitType)
+{
+    cachedStructure.clearToMaxUnsigned();
+    cachedPrototype.clear();
+    cachedPrototypeStructure.clearToMaxUnsigned();
+    cachedFunction.clear();
+    
+    ASSERT_UNUSED(jitType, jitType == JITCode::BaselineJIT);
+    
+    repatchBuffer.relink(callReturnLocation, cti_op_get_by_id_method_check);
+}
+
+void CodeBlock::unlinkCalls()
+{
+    if (!!m_alternative)
+        m_alternative->unlinkCalls();
+    if (!(m_callLinkInfos.size() || m_methodCallLinkInfos.size()))
+        return;
+    if (!m_globalData->canUseJIT())
+        return;
+    RepatchBuffer repatchBuffer(this);
+    for (size_t i = 0; i < m_callLinkInfos.size(); i++) {
+        if (!m_callLinkInfos[i].isLinked())
+            continue;
+        m_callLinkInfos[i].unlink(*m_globalData, repatchBuffer);
+    }
+}
+
+void CodeBlock::unlinkIncomingCalls()
+{
+    RepatchBuffer repatchBuffer(this);
+    while (m_incomingCalls.begin() != m_incomingCalls.end())
+        m_incomingCalls.begin()->unlink(*m_globalData, repatchBuffer);
+}
+#endif
+
+void CodeBlock::clearEvalCache()
+{
+    if (!!m_alternative)
+        m_alternative->clearEvalCache();
+    if (!m_rareData)
+        return;
+    m_rareData->m_evalCodeCache.clear();
+}
+
+template<typename T>
+inline void replaceExistingEntries(Vector<T>& target, Vector<T>& source)
+{
+    ASSERT(target.size() <= source.size());
+    for (size_t i = 0; i < target.size(); ++i)
+        target[i] = source[i];
+}
+
+void CodeBlock::copyPostParseDataFrom(CodeBlock* alternative)
+{
+    if (!alternative)
+        return;
+    
+    replaceExistingEntries(m_constantRegisters, alternative->m_constantRegisters);
+    replaceExistingEntries(m_functionDecls, alternative->m_functionDecls);
+    replaceExistingEntries(m_functionExprs, alternative->m_functionExprs);
+    if (!!m_rareData && !!alternative->m_rareData)
+        replaceExistingEntries(m_rareData->m_constantBuffers, alternative->m_rareData->m_constantBuffers);
+}
+
+void CodeBlock::copyPostParseDataFromAlternative()
+{
+    copyPostParseDataFrom(m_alternative.get());
+}
+
+#if ENABLE(JIT)
+CodeBlock* ProgramCodeBlock::replacement()
+{
+    return &static_cast<ProgramExecutable*>(ownerExecutable())->generatedBytecode();
+}
+
+CodeBlock* EvalCodeBlock::replacement()
+{
+    return &static_cast<EvalExecutable*>(ownerExecutable())->generatedBytecode();
+}
+
+CodeBlock* FunctionCodeBlock::replacement()
+{
+    return &static_cast<FunctionExecutable*>(ownerExecutable())->generatedBytecodeFor(m_isConstructor ? CodeForConstruct : CodeForCall);
+}
+
+JSObject* ProgramCodeBlock::compileOptimized(ExecState* exec, ScopeChainNode* scopeChainNode)
+{
+    if (replacement()->getJITType() == JITCode::nextTierJIT(getJITType()))
+        return 0;
+    JSObject* error = static_cast<ProgramExecutable*>(ownerExecutable())->compileOptimized(exec, scopeChainNode);
+    return error;
+}
+
+JSObject* EvalCodeBlock::compileOptimized(ExecState* exec, ScopeChainNode* scopeChainNode)
+{
+    if (replacement()->getJITType() == JITCode::nextTierJIT(getJITType()))
+        return 0;
+    JSObject* error = static_cast<EvalExecutable*>(ownerExecutable())->compileOptimized(exec, scopeChainNode);
+    return error;
+}
+
+JSObject* FunctionCodeBlock::compileOptimized(ExecState* exec, ScopeChainNode* scopeChainNode)
+{
+    if (replacement()->getJITType() == JITCode::nextTierJIT(getJITType()))
+        return 0;
+    JSObject* error = static_cast<FunctionExecutable*>(ownerExecutable())->compileOptimizedFor(exec, scopeChainNode, m_isConstructor ? CodeForConstruct : CodeForCall);
+    return error;
+}
+
+bool ProgramCodeBlock::canCompileWithDFG()
+{
+    return DFG::canCompileProgram(this);
+}
+
+bool EvalCodeBlock::canCompileWithDFG()
+{
+    return DFG::canCompileEval(this);
+}
+
+bool FunctionCodeBlock::canCompileWithDFG()
+{
+    if (m_isConstructor)
+        return DFG::canCompileFunctionForConstruct(this);
+    return DFG::canCompileFunctionForCall(this);
+}
+
+void ProgramCodeBlock::jettison()
+{
+    ASSERT(getJITType() != JITCode::BaselineJIT);
+    ASSERT(this == replacement());
+    static_cast<ProgramExecutable*>(ownerExecutable())->jettisonOptimizedCode(*globalData());
+}
+
+void EvalCodeBlock::jettison()
+{
+    ASSERT(getJITType() != JITCode::BaselineJIT);
+    ASSERT(this == replacement());
+    static_cast<EvalExecutable*>(ownerExecutable())->jettisonOptimizedCode(*globalData());
+}
+
+void FunctionCodeBlock::jettison()
+{
+    ASSERT(getJITType() != JITCode::BaselineJIT);
+    ASSERT(this == replacement());
+    static_cast<FunctionExecutable*>(ownerExecutable())->jettisonOptimizedCodeFor(*globalData(), m_isConstructor ? CodeForConstruct : CodeForCall);
+}
+#endif
+
+#if ENABLE(VALUE_PROFILER)
+bool CodeBlock::shouldOptimizeNow()
+{
+#if ENABLE(JIT_VERBOSE_OSR)
+    printf("Considering optimizing %p...\n", this);
+#endif
+
+#if ENABLE(VERBOSE_VALUE_PROFILE)
+    dumpValueProfiles();
+#endif
+
+    if (m_optimizationDelayCounter >= Options::maximumOptimizationDelay)
+        return true;
+    
+    unsigned numberOfLiveNonArgumentValueProfiles = 0;
+    unsigned numberOfSamplesInProfiles = 0; // If this divided by ValueProfile::numberOfBuckets equals numberOfValueProfiles() then value profiles are full.
+    for (unsigned i = 0; i < totalNumberOfValueProfiles(); ++i) {
+        ValueProfile* profile = getFromAllValueProfiles(i);
+        unsigned numSamples = profile->totalNumberOfSamples();
+        if (numSamples > ValueProfile::numberOfBuckets)
+            numSamples = ValueProfile::numberOfBuckets; // We don't want profiles that are extremely hot to be given more weight.
+        numberOfSamplesInProfiles += numSamples;
+        if (profile->m_bytecodeOffset < 0) {
+            profile->computeUpdatedPrediction();
+            continue;
+        }
+        if (profile->numberOfSamples() || profile->m_prediction != PredictNone)
+            numberOfLiveNonArgumentValueProfiles++;
+        profile->computeUpdatedPrediction();
+    }
+
+#if ENABLE(JIT_VERBOSE_OSR)
+    printf("Profile hotness: %lf, %lf\n", (double)numberOfLiveNonArgumentValueProfiles / numberOfValueProfiles(), (double)numberOfSamplesInProfiles / ValueProfile::numberOfBuckets / numberOfValueProfiles());
+#endif
+
+    if ((!numberOfValueProfiles() || (double)numberOfLiveNonArgumentValueProfiles / numberOfValueProfiles() >= Options::desiredProfileLivenessRate)
+        && (!totalNumberOfValueProfiles() || (double)numberOfSamplesInProfiles / ValueProfile::numberOfBuckets / totalNumberOfValueProfiles() >= Options::desiredProfileFullnessRate)
+        && static_cast<unsigned>(m_optimizationDelayCounter) + 1 >= Options::minimumOptimizationDelay)
+        return true;
+    
+    ASSERT(m_optimizationDelayCounter < std::numeric_limits<uint8_t>::max());
+    m_optimizationDelayCounter++;
+    optimizeAfterWarmUp();
+    return false;
+}
+#endif
+
+#if ENABLE(DFG_JIT)
+void CodeBlock::tallyFrequentExitSites()
+{
+    ASSERT(getJITType() == JITCode::DFGJIT);
+    ASSERT(alternative()->getJITType() == JITCode::BaselineJIT);
+    ASSERT(!!m_dfgData);
+    
+    CodeBlock* profiledBlock = alternative();
+    
+    for (unsigned i = 0; i < m_dfgData->osrExit.size(); ++i) {
+        DFG::OSRExit& exit = m_dfgData->osrExit[i];
+        
+        if (!exit.considerAddingAsFrequentExitSite(this, profiledBlock))
+            continue;
+        
+#if DFG_ENABLE(DEBUG_VERBOSE)
+        fprintf(stderr, "OSR exit #%u (bc#%u, @%u, %s) for code block %p occurred frequently; counting as frequent exit site.\n", i, exit.m_codeOrigin.bytecodeIndex, exit.m_nodeIndex, DFG::exitKindToString(exit.m_kind), this);
+#endif
+    }
+}
+#endif // ENABLE(DFG_JIT)
+
+#if ENABLE(VERBOSE_VALUE_PROFILE)
+void CodeBlock::dumpValueProfiles()
+{
+    fprintf(stderr, "ValueProfile for %p:\n", this);
+    for (unsigned i = 0; i < totalNumberOfValueProfiles(); ++i) {
+        ValueProfile* profile = getFromAllValueProfiles(i);
+        if (profile->m_bytecodeOffset < 0) {
+            ASSERT(profile->m_bytecodeOffset == -1);
+            fprintf(stderr, "   arg = %u: ", i);
+        } else
+            fprintf(stderr, "   bc = %d: ", profile->m_bytecodeOffset);
+        if (!profile->numberOfSamples() && profile->m_prediction == PredictNone) {
+            fprintf(stderr, "<empty>\n");
+            continue;
+        }
+        profile->dump(stderr);
+        fprintf(stderr, "\n");
+    }
+    fprintf(stderr, "RareCaseProfile for %p:\n", this);
+    for (unsigned i = 0; i < numberOfRareCaseProfiles(); ++i) {
+        RareCaseProfile* profile = rareCaseProfile(i);
+        fprintf(stderr, "   bc = %d: %u\n", profile->m_bytecodeOffset, profile->m_counter);
+    }
+    fprintf(stderr, "SpecialFastCaseProfile for %p:\n", this);
+    for (unsigned i = 0; i < numberOfSpecialFastCaseProfiles(); ++i) {
+        RareCaseProfile* profile = specialFastCaseProfile(i);
+        fprintf(stderr, "   bc = %d: %u\n", profile->m_bytecodeOffset, profile->m_counter);
+    }
+}
+#endif
+
+#ifndef NDEBUG
+bool CodeBlock::usesOpcode(OpcodeID opcodeID)
+{
+    Interpreter* interpreter = globalData()->interpreter;
+    Instruction* instructionsBegin = instructions().begin();
+    unsigned instructionCount = instructions().size();
+    
+    for (unsigned bytecodeOffset = 0; bytecodeOffset < instructionCount; ) {
+        switch (interpreter->getOpcodeID(instructionsBegin[bytecodeOffset].u.opcode)) {
+#define DEFINE_OP(curOpcode, length)        \
+        case curOpcode:                     \
+            if (curOpcode == opcodeID)      \
+                return true;                \
+            bytecodeOffset += length;       \
+            break;
+            FOR_EACH_OPCODE_ID(DEFINE_OP)
+#undef DEFINE_OP
+        default:
+            ASSERT_NOT_REACHED();
+            break;
+        }
+    }
+    
+    return false;
+}
+#endif
+
+} // namespace JSC