]> git.saurik.com Git - apple/javascriptcore.git/blobdiff - jit/JITPropertyAccess.cpp
JavaScriptCore-1097.13.tar.gz
[apple/javascriptcore.git] / jit / JITPropertyAccess.cpp
index ce3d3c1f385504a83359a1aeecee9f665a430256..8c7148c9def19fb56a32ed0ee61390483841e395 100644 (file)
@@ -50,24 +50,33 @@ using namespace std;
 namespace JSC {
 #if USE(JSVALUE64)
 
-JIT::CodePtr JIT::stringGetByValStubGenerator(JSGlobalData* globalData, ExecutablePool* pool)
+JIT::CodeRef JIT::stringGetByValStubGenerator(JSGlobalData* globalData)
 {
     JSInterfaceJIT jit;
     JumpList failures;
-    failures.append(jit.branchPtr(NotEqual, Address(regT0), TrustedImmPtr(globalData->jsStringVPtr)));
-    failures.append(jit.branchTest32(NonZero, Address(regT0, OBJECT_OFFSETOF(JSString, m_fiberCount))));
+    failures.append(jit.branchPtr(NotEqual, Address(regT0, JSCell::classInfoOffset()), TrustedImmPtr(&JSString::s_info)));
 
     // Load string length to regT2, and start the process of loading the data pointer into regT0
     jit.load32(Address(regT0, ThunkHelpers::jsStringLengthOffset()), regT2);
     jit.loadPtr(Address(regT0, ThunkHelpers::jsStringValueOffset()), regT0);
-    jit.loadPtr(Address(regT0, ThunkHelpers::stringImplDataOffset()), regT0);
-    
+    failures.append(jit.branchTest32(Zero, regT0));
+
     // Do an unsigned compare to simultaneously filter negative indices as well as indices that are too large
     failures.append(jit.branch32(AboveOrEqual, regT1, regT2));
     
     // Load the character
+    JumpList is16Bit;
+    JumpList cont8Bit;
+    // Load the string flags
+    jit.loadPtr(Address(regT0, ThunkHelpers::stringImplFlagsOffset()), regT2);
+    jit.loadPtr(Address(regT0, ThunkHelpers::stringImplDataOffset()), regT0);
+    is16Bit.append(jit.branchTest32(Zero, regT2, TrustedImm32(ThunkHelpers::stringImpl8BitFlag())));
+    jit.load8(BaseIndex(regT0, regT1, TimesOne, 0), regT0);
+    cont8Bit.append(jit.jump());
+    is16Bit.link(&jit);
     jit.load16(BaseIndex(regT0, regT1, TimesTwo, 0), regT0);
-    
+    cont8Bit.link(&jit);
+
     failures.append(jit.branch32(AboveOrEqual, regT0, TrustedImm32(0x100)));
     jit.move(TrustedImmPtr(globalData->smallStrings.singleCharacterStrings()), regT1);
     jit.loadPtr(BaseIndex(regT1, regT0, ScalePtr, 0), regT0);
@@ -77,8 +86,8 @@ JIT::CodePtr JIT::stringGetByValStubGenerator(JSGlobalData* globalData, Executab
     jit.move(TrustedImm32(0), regT0);
     jit.ret();
     
-    LinkBuffer patchBuffer(*globalData, &jit, pool);
-    return patchBuffer.finalizeCode().m_code;
+    LinkBuffer patchBuffer(*globalData, &jit, GLOBAL_THUNK_ID);
+    return patchBuffer.finalizeCode();
 }
 
 void JIT::emit_op_get_by_val(Instruction* currentInstruction)
@@ -99,7 +108,7 @@ void JIT::emit_op_get_by_val(Instruction* currentInstruction)
     zeroExtend32ToPtr(regT1, regT1);
 
     emitJumpSlowCaseIfNotJSCell(regT0, base);
-    addSlowCase(branchPtr(NotEqual, Address(regT0), TrustedImmPtr(m_globalData->jsArrayVPtr)));
+    addSlowCase(branchPtr(NotEqual, Address(regT0, JSCell::classInfoOffset()), TrustedImmPtr(&JSArray::s_info)));
 
     loadPtr(Address(regT0, JSArray::storageOffset()), regT2);
     addSlowCase(branch32(AboveOrEqual, regT1, Address(regT0, JSArray::vectorLengthOffset())));
@@ -107,6 +116,7 @@ void JIT::emit_op_get_by_val(Instruction* currentInstruction)
     loadPtr(BaseIndex(regT2, regT1, ScalePtr, OBJECT_OFFSETOF(ArrayStorage, m_vector[0])), regT0);
     addSlowCase(branchTestPtr(Zero, regT0));
 
+    emitValueProfilingSite();
     emitPutVirtualRegister(dst);
 }
 
@@ -120,8 +130,8 @@ void JIT::emitSlow_op_get_by_val(Instruction* currentInstruction, Vector<SlowCas
     linkSlowCaseIfNotJSCell(iter, base); // base cell check
     Jump nonCell = jump();
     linkSlowCase(iter); // base array check
-    Jump notString = branchPtr(NotEqual, Address(regT0), TrustedImmPtr(m_globalData->jsStringVPtr));
-    emitNakedCall(m_globalData->getCTIStub(stringGetByValStubGenerator));
+    Jump notString = branchPtr(NotEqual, Address(regT0, JSCell::classInfoOffset()), TrustedImmPtr(&JSString::s_info));
+    emitNakedCall(CodeLocationLabel(m_globalData->getCTIStub(stringGetByValStubGenerator).code()));
     Jump failed = branchTestPtr(Zero, regT0);
     emitPutVirtualRegister(dst, regT0);
     emitJumpSlowToHot(jump(), OPCODE_LENGTH(op_get_by_val));
@@ -136,11 +146,13 @@ void JIT::emitSlow_op_get_by_val(Instruction* currentInstruction, Vector<SlowCas
     stubCall.addArgument(base, regT2);
     stubCall.addArgument(property, regT2);
     stubCall.call(dst);
+
+    emitValueProfilingSite();
 }
 
 void JIT::compileGetDirectOffset(RegisterID base, RegisterID result, RegisterID offset, RegisterID scratch)
 {
-    loadPtr(Address(base, OBJECT_OFFSETOF(JSObject, m_propertyStorage)), scratch);
+    loadPtr(Address(base, JSObject::offsetOfPropertyStorage()), scratch);
     loadPtr(BaseIndex(scratch, offset, ScalePtr, 0), result);
 }
 
@@ -197,53 +209,65 @@ void JIT::emit_op_put_by_val(Instruction* currentInstruction)
     // See comment in op_get_by_val.
     zeroExtend32ToPtr(regT1, regT1);
     emitJumpSlowCaseIfNotJSCell(regT0, base);
-    addSlowCase(branchPtr(NotEqual, Address(regT0), TrustedImmPtr(m_globalData->jsArrayVPtr)));
+    addSlowCase(branchPtr(NotEqual, Address(regT0, JSCell::classInfoOffset()), TrustedImmPtr(&JSArray::s_info)));
     addSlowCase(branch32(AboveOrEqual, regT1, Address(regT0, JSArray::vectorLengthOffset())));
 
     loadPtr(Address(regT0, JSArray::storageOffset()), regT2);
     Jump empty = branchTestPtr(Zero, BaseIndex(regT2, regT1, ScalePtr, OBJECT_OFFSETOF(ArrayStorage, m_vector[0])));
 
     Label storeResult(this);
-    emitGetVirtualRegister(value, regT0);
-    storePtr(regT0, BaseIndex(regT2, regT1, ScalePtr, OBJECT_OFFSETOF(ArrayStorage, m_vector[0])));
+    emitGetVirtualRegister(value, regT3);
+    storePtr(regT3, BaseIndex(regT2, regT1, ScalePtr, OBJECT_OFFSETOF(ArrayStorage, m_vector[0])));
     Jump end = jump();
     
     empty.link(this);
     add32(TrustedImm32(1), Address(regT2, OBJECT_OFFSETOF(ArrayStorage, m_numValuesInVector)));
     branch32(Below, regT1, Address(regT2, OBJECT_OFFSETOF(ArrayStorage, m_length))).linkTo(storeResult, this);
 
-    move(regT1, regT0);
-    add32(TrustedImm32(1), regT0);
-    store32(regT0, Address(regT2, OBJECT_OFFSETOF(ArrayStorage, m_length)));
+    add32(TrustedImm32(1), regT1);
+    store32(regT1, Address(regT2, OBJECT_OFFSETOF(ArrayStorage, m_length)));
+    sub32(TrustedImm32(1), regT1);
     jump().linkTo(storeResult, this);
 
     end.link(this);
+
+    emitWriteBarrier(regT0, regT3, regT1, regT3, ShouldFilterImmediates, WriteBarrierForPropertyAccess);
 }
 
-void JIT::emit_op_put_by_index(Instruction* currentInstruction)
+void JIT::emitSlow_op_put_by_val(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    JITStubCall stubCall(this, cti_op_put_by_index);
-    stubCall.addArgument(currentInstruction[1].u.operand, regT2);
-    stubCall.addArgument(TrustedImm32(currentInstruction[2].u.operand));
-    stubCall.addArgument(currentInstruction[3].u.operand, regT2);
-    stubCall.call();
+    unsigned base = currentInstruction[1].u.operand;
+    unsigned property = currentInstruction[2].u.operand;
+    unsigned value = currentInstruction[3].u.operand;
+
+    linkSlowCase(iter); // property int32 check
+    linkSlowCaseIfNotJSCell(iter, base); // base cell check
+    linkSlowCase(iter); // base not array check
+    linkSlowCase(iter); // in vector check
+
+    JITStubCall stubPutByValCall(this, cti_op_put_by_val);
+    stubPutByValCall.addArgument(regT0);
+    stubPutByValCall.addArgument(property, regT2);
+    stubPutByValCall.addArgument(value, regT2);
+    stubPutByValCall.call();
 }
 
-void JIT::emit_op_put_getter(Instruction* currentInstruction)
+void JIT::emit_op_put_by_index(Instruction* currentInstruction)
 {
-    JITStubCall stubCall(this, cti_op_put_getter);
+    JITStubCall stubCall(this, cti_op_put_by_index);
     stubCall.addArgument(currentInstruction[1].u.operand, regT2);
-    stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[2].u.operand)));
+    stubCall.addArgument(TrustedImm32(currentInstruction[2].u.operand));
     stubCall.addArgument(currentInstruction[3].u.operand, regT2);
     stubCall.call();
 }
 
-void JIT::emit_op_put_setter(Instruction* currentInstruction)
+void JIT::emit_op_put_getter_setter(Instruction* currentInstruction)
 {
-    JITStubCall stubCall(this, cti_op_put_setter);
+    JITStubCall stubCall(this, cti_op_put_getter_setter);
     stubCall.addArgument(currentInstruction[1].u.operand, regT2);
     stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[2].u.operand)));
     stubCall.addArgument(currentInstruction[3].u.operand, regT2);
+    stubCall.addArgument(currentInstruction[4].u.operand, regT2);
     stubCall.call();
 }
 
@@ -255,67 +279,6 @@ void JIT::emit_op_del_by_id(Instruction* currentInstruction)
     stubCall.call(currentInstruction[1].u.operand);
 }
 
-
-#if !ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS)
-
-/* ------------------------------ BEGIN: !ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS) ------------------------------ */
-
-// Treat these as nops - the call will be handed as a regular get_by_id/op_call pair.
-void JIT::emit_op_method_check(Instruction*) {}
-void JIT::emitSlow_op_method_check(Instruction*, Vector<SlowCaseEntry>::iterator&) { ASSERT_NOT_REACHED(); }
-#if ENABLE(JIT_OPTIMIZE_METHOD_CALLS)
-#error "JIT_OPTIMIZE_METHOD_CALLS requires JIT_OPTIMIZE_PROPERTY_ACCESS"
-#endif
-
-void JIT::emit_op_get_by_id(Instruction* currentInstruction)
-{
-    unsigned resultVReg = currentInstruction[1].u.operand;
-    unsigned baseVReg = currentInstruction[2].u.operand;
-    Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
-
-    emitGetVirtualRegister(baseVReg, regT0);
-    JITStubCall stubCall(this, cti_op_get_by_id_generic);
-    stubCall.addArgument(regT0);
-    stubCall.addArgument(TrustedImmPtr(ident));
-    stubCall.call(resultVReg);
-
-    m_propertyAccessInstructionIndex++;
-}
-
-void JIT::emitSlow_op_get_by_id(Instruction*, Vector<SlowCaseEntry>::iterator&)
-{
-    ASSERT_NOT_REACHED();
-}
-
-void JIT::emit_op_put_by_id(Instruction* currentInstruction)
-{
-    unsigned baseVReg = currentInstruction[1].u.operand;
-    Identifier* ident = &(m_codeBlock->identifier(currentInstruction[2].u.operand));
-    unsigned valueVReg = currentInstruction[3].u.operand;
-    unsigned direct = currentInstruction[8].u.operand;
-
-    emitGetVirtualRegisters(baseVReg, regT0, valueVReg, regT1);
-
-    JITStubCall stubCall(this, direct ? cti_op_put_by_id_direct_generic, cti_op_put_by_id_generic);
-    stubCall.addArgument(regT0);
-    stubCall.addArgument(TrustedImmPtr(ident));
-    stubCall.addArgument(regT1);
-    stubCall.call();
-
-    m_propertyAccessInstructionIndex++;
-}
-
-void JIT::emitSlow_op_put_by_id(Instruction*, Vector<SlowCaseEntry>::iterator&)
-{
-    ASSERT_NOT_REACHED();
-}
-
-#else // !ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS)
-
-/* ------------------------------ BEGIN: ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS) ------------------------------ */
-
-#if ENABLE(JIT_OPTIMIZE_METHOD_CALLS)
-
 void JIT::emit_op_method_check(Instruction* currentInstruction)
 {
     // Assert that the following instruction is a get_by_id.
@@ -329,7 +292,7 @@ void JIT::emit_op_method_check(Instruction* currentInstruction)
     emitGetVirtualRegister(baseVReg, regT0);
 
     // Do the method check - check the object & its prototype's structure inline (this is the common case).
-    m_methodCallCompilationInfo.append(MethodCallCompilationInfo(m_propertyAccessInstructionIndex));
+    m_methodCallCompilationInfo.append(MethodCallCompilationInfo(m_bytecodeOffset, m_propertyAccessCompilationInfo.size()));
     MethodCallCompilationInfo& info = m_methodCallCompilationInfo.last();
 
     Jump notCell = emitJumpIfNotJSCell(regT0);
@@ -347,10 +310,6 @@ void JIT::emit_op_method_check(Instruction* currentInstruction)
 
     Jump match = jump();
 
-    ASSERT_JIT_OFFSET_UNUSED(protoObj, differenceBetween(info.structureToCompare, protoObj), patchOffsetMethodCheckProtoObj);
-    ASSERT_JIT_OFFSET(differenceBetween(info.structureToCompare, protoStructureToCompare), patchOffsetMethodCheckProtoStruct);
-    ASSERT_JIT_OFFSET_UNUSED(putFunction, differenceBetween(info.structureToCompare, putFunction), patchOffsetMethodCheckPutFunction);
-
     // Link the failure cases here.
     notCell.link(this);
     structureCheck.link(this);
@@ -358,13 +317,16 @@ void JIT::emit_op_method_check(Instruction* currentInstruction)
 
     // Do a regular(ish) get_by_id (the slow case will be link to
     // cti_op_get_by_id_method_check instead of cti_op_get_by_id.
-    compileGetByIdHotPath(resultVReg, baseVReg, ident, m_propertyAccessInstructionIndex++);
+    compileGetByIdHotPath(baseVReg, ident);
 
     match.link(this);
+    emitValueProfilingSite(m_bytecodeOffset + OPCODE_LENGTH(op_method_check));
     emitPutVirtualRegister(resultVReg);
 
     // We've already generated the following get_by_id, so make sure it's skipped over.
     m_bytecodeOffset += OPCODE_LENGTH(op_get_by_id);
+
+    m_propertyAccessCompilationInfo.last().addMethodCheckInfo(info.structureToCompare, protoObj, protoStructureToCompare, putFunction);
 }
 
 void JIT::emitSlow_op_method_check(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
@@ -375,19 +337,12 @@ void JIT::emitSlow_op_method_check(Instruction* currentInstruction, Vector<SlowC
     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
 
     compileGetByIdSlowCase(resultVReg, baseVReg, ident, iter, true);
+    emitValueProfilingSite(m_bytecodeOffset + OPCODE_LENGTH(op_method_check));
 
     // We've already generated the following get_by_id, so make sure it's skipped over.
     m_bytecodeOffset += OPCODE_LENGTH(op_get_by_id);
 }
 
-#else //!ENABLE(JIT_OPTIMIZE_METHOD_CALLS)
-
-// Treat these as nops - the call will be handed as a regular get_by_id/op_call pair.
-void JIT::emit_op_method_check(Instruction*) {}
-void JIT::emitSlow_op_method_check(Instruction*, Vector<SlowCaseEntry>::iterator&) { ASSERT_NOT_REACHED(); }
-
-#endif
-
 void JIT::emit_op_get_by_id(Instruction* currentInstruction)
 {
     unsigned resultVReg = currentInstruction[1].u.operand;
@@ -395,11 +350,12 @@ void JIT::emit_op_get_by_id(Instruction* currentInstruction)
     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
 
     emitGetVirtualRegister(baseVReg, regT0);
-    compileGetByIdHotPath(resultVReg, baseVReg, ident, m_propertyAccessInstructionIndex++);
+    compileGetByIdHotPath(baseVReg, ident);
+    emitValueProfilingSite();
     emitPutVirtualRegister(resultVReg);
 }
 
-void JIT::compileGetByIdHotPath(int, int baseVReg, Identifier*, unsigned propertyAccessInstructionIndex)
+void JIT::compileGetByIdHotPath(int baseVReg, Identifier*)
 {
     // As for put_by_id, get_by_id requires the offset of the Structure and the offset of the access to be patched.
     // Additionally, for get_by_id we need patch the offset of the branch to the slow case (we patch this to jump
@@ -411,23 +367,19 @@ void JIT::compileGetByIdHotPath(int, int baseVReg, Identifier*, unsigned propert
     BEGIN_UNINTERRUPTED_SEQUENCE(sequenceGetByIdHotPath);
 
     Label hotPathBegin(this);
-    m_propertyAccessCompilationInfo[propertyAccessInstructionIndex].hotPathBegin = hotPathBegin;
 
     DataLabelPtr structureToCompare;
-    Jump structureCheck = branchPtrWithPatch(NotEqual, Address(regT0, JSCell::structureOffset()), structureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure)));
+    PatchableJump structureCheck = patchableBranchPtrWithPatch(NotEqual, Address(regT0, JSCell::structureOffset()), structureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure)));
     addSlowCase(structureCheck);
-    ASSERT_JIT_OFFSET(differenceBetween(hotPathBegin, structureToCompare), patchOffsetGetByIdStructure);
-    ASSERT_JIT_OFFSET(differenceBetween(hotPathBegin, structureCheck), patchOffsetGetByIdBranchToSlowCase)
 
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSObject, m_propertyStorage)), regT0);
+    loadPtr(Address(regT0, JSObject::offsetOfPropertyStorage()), regT0);
     DataLabelCompact displacementLabel = loadPtrWithCompactAddressOffsetPatch(Address(regT0, patchGetByIdDefaultOffset), regT0);
-    ASSERT_JIT_OFFSET_UNUSED(displacementLabel, differenceBetween(hotPathBegin, displacementLabel), patchOffsetGetByIdPropertyMapOffset);
 
     Label putResult(this);
 
     END_UNINTERRUPTED_SEQUENCE(sequenceGetByIdHotPath);
 
-    ASSERT_JIT_OFFSET(differenceBetween(hotPathBegin, putResult), patchOffsetGetByIdPutResult);
+    m_propertyAccessCompilationInfo.append(PropertyStubCompilationInfo(PropertyStubGetById, m_bytecodeOffset, hotPathBegin, structureToCompare, structureCheck, displacementLabel, putResult));
 }
 
 void JIT::emitSlow_op_get_by_id(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
@@ -437,6 +389,7 @@ void JIT::emitSlow_op_get_by_id(Instruction* currentInstruction, Vector<SlowCase
     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[3].u.operand));
 
     compileGetByIdSlowCase(resultVReg, baseVReg, ident, iter, false);
+    emitValueProfilingSite();
 }
 
 void JIT::compileGetByIdSlowCase(int resultVReg, int baseVReg, Identifier* ident, Vector<SlowCaseEntry>::iterator& iter, bool isMethodCheck)
@@ -452,9 +405,7 @@ void JIT::compileGetByIdSlowCase(int resultVReg, int baseVReg, Identifier* ident
 
     BEGIN_UNINTERRUPTED_SEQUENCE(sequenceGetByIdSlowCase);
 
-#ifndef NDEBUG
     Label coldPathBegin(this);
-#endif
     JITStubCall stubCall(this, isMethodCheck ? cti_op_get_by_id_method_check : cti_op_get_by_id);
     stubCall.addArgument(regT0);
     stubCall.addArgument(TrustedImmPtr(ident));
@@ -462,11 +413,8 @@ void JIT::compileGetByIdSlowCase(int resultVReg, int baseVReg, Identifier* ident
 
     END_UNINTERRUPTED_SEQUENCE(sequenceGetByIdSlowCase);
 
-    ASSERT_JIT_OFFSET(differenceBetween(coldPathBegin, call), patchOffsetGetByIdSlowCaseCall);
-
     // Track the location of the call; this will be used to recover patch information.
-    m_propertyAccessCompilationInfo[m_propertyAccessInstructionIndex].callReturnLocation = call;
-    m_propertyAccessInstructionIndex++;
+    m_propertyAccessCompilationInfo[m_propertyAccessInstructionIndex++].slowCaseInfo(PropertyStubGetById, coldPathBegin, call);
 }
 
 void JIT::emit_op_put_by_id(Instruction* currentInstruction)
@@ -474,8 +422,6 @@ void JIT::emit_op_put_by_id(Instruction* currentInstruction)
     unsigned baseVReg = currentInstruction[1].u.operand;
     unsigned valueVReg = currentInstruction[3].u.operand;
 
-    unsigned propertyAccessInstructionIndex = m_propertyAccessInstructionIndex++;
-
     // In order to be able to patch both the Structure, and the object offset, we store one pointer,
     // to just after the arguments have been loaded into registers 'hotPathBegin', and we generate code
     // such that the Structure & offset are always at the same distance from this.
@@ -488,19 +434,19 @@ void JIT::emit_op_put_by_id(Instruction* currentInstruction)
     BEGIN_UNINTERRUPTED_SEQUENCE(sequencePutById);
 
     Label hotPathBegin(this);
-    m_propertyAccessCompilationInfo[propertyAccessInstructionIndex].hotPathBegin = hotPathBegin;
 
     // It is important that the following instruction plants a 32bit immediate, in order that it can be patched over.
     DataLabelPtr structureToCompare;
     addSlowCase(branchPtrWithPatch(NotEqual, Address(regT0, JSCell::structureOffset()), structureToCompare, TrustedImmPtr(reinterpret_cast<void*>(patchGetByIdDefaultStructure))));
-    ASSERT_JIT_OFFSET(differenceBetween(hotPathBegin, structureToCompare), patchOffsetPutByIdStructure);
 
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSObject, m_propertyStorage)), regT0);
-    DataLabel32 displacementLabel = storePtrWithAddressOffsetPatch(regT1, Address(regT0, patchPutByIdDefaultOffset));
+    loadPtr(Address(regT0, JSObject::offsetOfPropertyStorage()), regT2);
+    DataLabel32 displacementLabel = storePtrWithAddressOffsetPatch(regT1, Address(regT2, patchPutByIdDefaultOffset));
 
     END_UNINTERRUPTED_SEQUENCE(sequencePutById);
 
-    ASSERT_JIT_OFFSET_UNUSED(displacementLabel, differenceBetween(hotPathBegin, displacementLabel), patchOffsetPutByIdPropertyMapOffset);
+    emitWriteBarrier(regT0, regT1, regT2, regT3, ShouldFilterImmediates, WriteBarrierForPropertyAccess);
+
+    m_propertyAccessCompilationInfo.append(PropertyStubCompilationInfo(PropertyStubPutById, m_bytecodeOffset, hotPathBegin, structureToCompare, displacementLabel));
 }
 
 void JIT::emitSlow_op_put_by_id(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
@@ -509,8 +455,6 @@ void JIT::emitSlow_op_put_by_id(Instruction* currentInstruction, Vector<SlowCase
     Identifier* ident = &(m_codeBlock->identifier(currentInstruction[2].u.operand));
     unsigned direct = currentInstruction[8].u.operand;
 
-    unsigned propertyAccessInstructionIndex = m_propertyAccessInstructionIndex++;
-
     linkSlowCaseIfNotJSCell(iter, baseVReg);
     linkSlowCase(iter);
 
@@ -521,37 +465,30 @@ void JIT::emitSlow_op_put_by_id(Instruction* currentInstruction, Vector<SlowCase
     Call call = stubCall.call();
 
     // Track the location of the call; this will be used to recover patch information.
-    m_propertyAccessCompilationInfo[propertyAccessInstructionIndex].callReturnLocation = call;
+    m_propertyAccessCompilationInfo[m_propertyAccessInstructionIndex++].slowCaseInfo(PropertyStubPutById, call);
 }
 
 // Compile a store into an object's property storage.  May overwrite the
 // value in objectReg.
-void JIT::compilePutDirectOffset(RegisterID base, RegisterID value, Structure* structure, size_t cachedOffset)
+void JIT::compilePutDirectOffset(RegisterID base, RegisterID value, size_t cachedOffset)
 {
     int offset = cachedOffset * sizeof(JSValue);
-    if (structure->isUsingInlineStorage())
-        offset += JSObject::offsetOfInlineStorage();
-    else
-        loadPtr(Address(base, OBJECT_OFFSETOF(JSObject, m_propertyStorage)), base);
+    loadPtr(Address(base, JSObject::offsetOfPropertyStorage()), base);
     storePtr(value, Address(base, offset));
 }
 
 // Compile a load from an object's property storage.  May overwrite base.
-void JIT::compileGetDirectOffset(RegisterID base, RegisterID result, Structure* structure, size_t cachedOffset)
+void JIT::compileGetDirectOffset(RegisterID base, RegisterID result, size_t cachedOffset)
 {
     int offset = cachedOffset * sizeof(JSValue);
-    if (structure->isUsingInlineStorage()) {
-        offset += JSObject::offsetOfInlineStorage();
-        loadPtr(Address(base, offset), result);
-    } else {
-        loadPtr(Address(base, OBJECT_OFFSETOF(JSObject, m_propertyStorage)), result);
-        loadPtr(Address(result, offset), result);
-    }
+    loadPtr(Address(base, JSObject::offsetOfPropertyStorage()), result);
+    loadPtr(Address(result, offset), result);
 }
 
 void JIT::compileGetDirectOffset(JSObject* base, RegisterID result, size_t cachedOffset)
 {
-    loadPtr(static_cast<void*>(&base->m_propertyStorage[cachedOffset]), result);
+    loadPtr(base->addressOfPropertyStorage(), result);
+    loadPtr(Address(result, cachedOffset * sizeof(WriteBarrier<Unknown>)), result);
 }
 
 void JIT::privateCompilePutByIdTransition(StructureStubInfo* stubInfo, Structure* oldStructure, Structure* newStructure, size_t cachedOffset, StructureChain* chain, ReturnAddressPtr returnAddress, bool direct)
@@ -560,16 +497,29 @@ void JIT::privateCompilePutByIdTransition(StructureStubInfo* stubInfo, Structure
     // Check eax is an object of the right Structure.
     failureCases.append(emitJumpIfNotJSCell(regT0));
     failureCases.append(branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(oldStructure)));
+    
     testPrototype(oldStructure->storedPrototype(), failureCases);
+    
+    ASSERT(oldStructure->storedPrototype().isNull() || oldStructure->storedPrototype().asCell()->structure() == chain->head()->get());
 
     // ecx = baseObject->m_structure
     if (!direct) {
-        for (WriteBarrier<Structure>* it = chain->head(); *it; ++it)
+        for (WriteBarrier<Structure>* it = chain->head(); *it; ++it) {
+            ASSERT((*it)->storedPrototype().isNull() || (*it)->storedPrototype().asCell()->structure() == it[1].get());
             testPrototype((*it)->storedPrototype(), failureCases);
+        }
     }
 
-    Call callTarget;
-
+    // If we succeed in all of our checks, and the code was optimizable, then make sure we
+    // decrement the rare case counter.
+#if ENABLE(VALUE_PROFILER)
+    if (m_codeBlock->canCompileWithDFG()) {
+        sub32(
+            TrustedImm32(1),
+            AbsoluteAddress(&m_codeBlock->rareCaseProfileForBytecodeOffset(stubInfo->bytecodeIndex)->m_counter));
+    }
+#endif
+    
     // emit a call only if storage realloc is needed
     bool willNeedStorageRealloc = oldStructure->propertyStorageCapacity() != newStructure->propertyStorageCapacity();
     if (willNeedStorageRealloc) {
@@ -582,17 +532,20 @@ void JIT::privateCompilePutByIdTransition(StructureStubInfo* stubInfo, Structure
         stubCall.skipArgument(); // ident
         stubCall.skipArgument(); // value
         stubCall.addArgument(TrustedImm32(oldStructure->propertyStorageCapacity()));
-        stubCall.addArgument(TrustedImm32(newStructure->propertyStorageCapacity()));
+        stubCall.addArgument(TrustedImmPtr(newStructure));
         stubCall.call(regT0);
         emitGetJITStubArg(2, regT1);
 
         restoreReturnAddressBeforeReturn(regT3);
     }
 
-    storePtrWithWriteBarrier(TrustedImmPtr(newStructure), regT0, Address(regT0, JSCell::structureOffset()));
+    // Planting the new structure triggers the write barrier so we need
+    // an unconditional barrier here.
+    emitWriteBarrier(regT0, regT1, regT2, regT3, UnconditionalWriteBarrier, WriteBarrierForPropertyAccess);
 
-    // write the value
-    compilePutDirectOffset(regT0, regT1, newStructure, cachedOffset);
+    ASSERT(newStructure->classInfo() == oldStructure->classInfo());
+    storePtr(TrustedImmPtr(newStructure), Address(regT0, JSCell::structureOffset()));
+    compilePutDirectOffset(regT0, regT1, cachedOffset);
 
     ret();
     
@@ -601,7 +554,7 @@ void JIT::privateCompilePutByIdTransition(StructureStubInfo* stubInfo, Structure
     restoreArgumentReferenceForTrampoline();
     Call failureCall = tailRecursiveCall();
 
-    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock->executablePool());
+    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock);
 
     patchBuffer.link(failureCall, FunctionPtr(direct ? cti_op_put_by_id_direct_fail : cti_op_put_by_id_fail));
 
@@ -610,10 +563,9 @@ void JIT::privateCompilePutByIdTransition(StructureStubInfo* stubInfo, Structure
         patchBuffer.link(m_calls[0].from, FunctionPtr(cti_op_put_by_id_transition_realloc));
     }
     
-    CodeLocationLabel entryLabel = patchBuffer.finalizeCodeAddendum();
-    stubInfo->stubRoutine = entryLabel;
+    stubInfo->stubRoutine = patchBuffer.finalizeCode();
     RepatchBuffer repatchBuffer(m_codeBlock);
-    repatchBuffer.relinkCallerToTrampoline(returnAddress, entryLabel);
+    repatchBuffer.relinkCallerToTrampoline(returnAddress, CodeLocationLabel(stubInfo->stubRoutine.code()));
 }
 
 void JIT::patchGetByIdSelf(CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* structure, size_t cachedOffset, ReturnAddressPtr returnAddress)
@@ -627,8 +579,8 @@ void JIT::patchGetByIdSelf(CodeBlock* codeBlock, StructureStubInfo* stubInfo, St
     int offset = sizeof(JSValue) * cachedOffset;
 
     // Patch the offset into the propoerty map to load from, then patch the Structure to look for.
-    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(patchOffsetGetByIdStructure), structure);
-    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(patchOffsetGetByIdPropertyMapOffset), offset);
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.get.structureToCompare), structure);
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(stubInfo->patch.baseline.u.get.displacementLabel), offset);
 }
 
 void JIT::patchPutByIdReplace(CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* structure, size_t cachedOffset, ReturnAddressPtr returnAddress, bool direct)
@@ -642,8 +594,8 @@ void JIT::patchPutByIdReplace(CodeBlock* codeBlock, StructureStubInfo* stubInfo,
     int offset = sizeof(JSValue) * cachedOffset;
 
     // Patch the offset into the propoerty map to load from, then patch the Structure to look for.
-    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(patchOffsetPutByIdStructure), structure);
-    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabel32AtOffset(patchOffsetPutByIdPropertyMapOffset), offset);
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.put.structureToCompare), structure);
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabel32AtOffset(stubInfo->patch.baseline.u.put.displacementLabel), offset);
 }
 
 void JIT::privateCompilePatchGetArrayLength(ReturnAddressPtr returnAddress)
@@ -651,7 +603,7 @@ void JIT::privateCompilePatchGetArrayLength(ReturnAddressPtr returnAddress)
     StructureStubInfo* stubInfo = &m_codeBlock->getStubInfo(returnAddress);
 
     // Check eax is an array
-    Jump failureCases1 = branchPtr(NotEqual, Address(regT0), TrustedImmPtr(m_globalData->jsArrayVPtr));
+    Jump failureCases1 = branchPtr(NotEqual, Address(regT0, JSCell::classInfoOffset()), TrustedImmPtr(&JSArray::s_info));
 
     // Checks out okay! - get the length from the storage
     loadPtr(Address(regT0, JSArray::storageOffset()), regT3);
@@ -661,24 +613,23 @@ void JIT::privateCompilePatchGetArrayLength(ReturnAddressPtr returnAddress)
     emitFastArithIntToImmNoCheck(regT2, regT0);
     Jump success = jump();
 
-    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock->executablePool());
+    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock);
 
     // Use the patch information to link the failure cases back to the original slow case routine.
-    CodeLocationLabel slowCaseBegin = stubInfo->callReturnLocation.labelAtOffset(-patchOffsetGetByIdSlowCaseCall);
+    CodeLocationLabel slowCaseBegin = stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin);
     patchBuffer.link(failureCases1, slowCaseBegin);
     patchBuffer.link(failureCases2, slowCaseBegin);
 
     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
-    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
+    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 
     // Track the stub we have created so that it will be deleted later.
-    CodeLocationLabel entryLabel = patchBuffer.finalizeCodeAddendum();
-    stubInfo->stubRoutine = entryLabel;
+    stubInfo->stubRoutine = patchBuffer.finalizeCode();
 
     // Finally patch the jump to slow case back in the hot path to jump here instead.
-    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
+    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
     RepatchBuffer repatchBuffer(m_codeBlock);
-    repatchBuffer.relink(jumpLocation, entryLabel);
+    repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubInfo->stubRoutine.code()));
 
     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_array_fail));
@@ -719,15 +670,15 @@ void JIT::privateCompileGetByIdProto(StructureStubInfo* stubInfo, Structure* str
     } else
         compileGetDirectOffset(protoObject, regT0, cachedOffset);
     Jump success = jump();
-    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock->executablePool());
+    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock);
 
     // Use the patch information to link the failure cases back to the original slow case routine.
-    CodeLocationLabel slowCaseBegin = stubInfo->callReturnLocation.labelAtOffset(-patchOffsetGetByIdSlowCaseCall);
+    CodeLocationLabel slowCaseBegin = stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin);
     patchBuffer.link(failureCases1, slowCaseBegin);
     patchBuffer.link(failureCases2, slowCaseBegin);
 
     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
-    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
+    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 
     if (needsStubLink) {
         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
@@ -736,13 +687,12 @@ void JIT::privateCompileGetByIdProto(StructureStubInfo* stubInfo, Structure* str
         }
     }
     // Track the stub we have created so that it will be deleted later.
-    CodeLocationLabel entryLabel = patchBuffer.finalizeCodeAddendum();
-    stubInfo->stubRoutine = entryLabel;
+    stubInfo->stubRoutine = patchBuffer.finalizeCode();
 
     // Finally patch the jump to slow case back in the hot path to jump here instead.
-    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
+    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
     RepatchBuffer repatchBuffer(m_codeBlock);
-    repatchBuffer.relink(jumpLocation, entryLabel);
+    repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubInfo->stubRoutine.code()));
 
     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_proto_list));
@@ -752,9 +702,10 @@ void JIT::privateCompileGetByIdSelfList(StructureStubInfo* stubInfo, Polymorphic
 {
     Jump failureCase = checkStructure(regT0, structure);
     bool needsStubLink = false;
+    bool isDirect = false;
     if (slot.cachedPropertyType() == PropertySlot::Getter) {
         needsStubLink = true;
-        compileGetDirectOffset(regT0, regT1, structure, cachedOffset);
+        compileGetDirectOffset(regT0, regT1, cachedOffset);
         JITStubCall stubCall(this, cti_op_get_by_id_getter_stub);
         stubCall.addArgument(regT1);
         stubCall.addArgument(regT0);
@@ -768,11 +719,13 @@ void JIT::privateCompileGetByIdSelfList(StructureStubInfo* stubInfo, Polymorphic
         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
         stubCall.call();
-    } else
-        compileGetDirectOffset(regT0, regT0, structure, cachedOffset);
+    } else {
+        isDirect = true;
+        compileGetDirectOffset(regT0, regT0, cachedOffset);
+    }
     Jump success = jump();
 
-    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock->executablePool());
+    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock);
 
     if (needsStubLink) {
         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
@@ -782,23 +735,23 @@ void JIT::privateCompileGetByIdSelfList(StructureStubInfo* stubInfo, Polymorphic
     }
 
     // Use the patch information to link the failure cases back to the original slow case routine.
-    CodeLocationLabel lastProtoBegin = polymorphicStructures->list[currentIndex - 1].stubRoutine;
+    CodeLocationLabel lastProtoBegin = CodeLocationLabel(polymorphicStructures->list[currentIndex - 1].stubRoutine.code());
     if (!lastProtoBegin)
-        lastProtoBegin = stubInfo->callReturnLocation.labelAtOffset(-patchOffsetGetByIdSlowCaseCall);
+        lastProtoBegin = stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin);
 
     patchBuffer.link(failureCase, lastProtoBegin);
 
     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
-    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
+    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 
-    CodeLocationLabel entryLabel = patchBuffer.finalizeCodeAddendum();
+    MacroAssemblerCodeRef stubCode = patchBuffer.finalizeCode();
 
-    polymorphicStructures->list[currentIndex].set(*m_globalData, m_codeBlock->ownerExecutable(), entryLabel, structure);
+    polymorphicStructures->list[currentIndex].set(*m_globalData, m_codeBlock->ownerExecutable(), stubCode, structure, isDirect);
 
     // Finally patch the jump to slow case back in the hot path to jump here instead.
-    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
+    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
     RepatchBuffer repatchBuffer(m_codeBlock);
-    repatchBuffer.relink(jumpLocation, entryLabel);
+    repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubCode.code()));
 }
 
 void JIT::privateCompileGetByIdProtoList(StructureStubInfo* stubInfo, PolymorphicAccessStructureList* prototypeStructures, int currentIndex, Structure* structure, Structure* prototypeStructure, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, CallFrame* callFrame)
@@ -816,6 +769,7 @@ void JIT::privateCompileGetByIdProtoList(StructureStubInfo* stubInfo, Polymorphi
 
     // Checks out okay!
     bool needsStubLink = false;
+    bool isDirect = false;
     if (slot.cachedPropertyType() == PropertySlot::Getter) {
         needsStubLink = true;
         compileGetDirectOffset(protoObject, regT1, cachedOffset);
@@ -832,12 +786,14 @@ void JIT::privateCompileGetByIdProtoList(StructureStubInfo* stubInfo, Polymorphi
         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
         stubCall.call();
-    } else
+    } else {
+        isDirect = true;
         compileGetDirectOffset(protoObject, regT0, cachedOffset);
+    }
 
     Jump success = jump();
 
-    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock->executablePool());
+    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock);
 
     if (needsStubLink) {
         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
@@ -847,20 +803,20 @@ void JIT::privateCompileGetByIdProtoList(StructureStubInfo* stubInfo, Polymorphi
     }
 
     // Use the patch information to link the failure cases back to the original slow case routine.
-    CodeLocationLabel lastProtoBegin = prototypeStructures->list[currentIndex - 1].stubRoutine;
+    CodeLocationLabel lastProtoBegin = CodeLocationLabel(prototypeStructures->list[currentIndex - 1].stubRoutine.code());
     patchBuffer.link(failureCases1, lastProtoBegin);
     patchBuffer.link(failureCases2, lastProtoBegin);
 
     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
-    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
+    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 
-    CodeLocationLabel entryLabel = patchBuffer.finalizeCodeAddendum();
-    prototypeStructures->list[currentIndex].set(*m_globalData, m_codeBlock->ownerExecutable(), entryLabel, structure, prototypeStructure);
+    MacroAssemblerCodeRef stubCode = patchBuffer.finalizeCode();
+    prototypeStructures->list[currentIndex].set(*m_globalData, m_codeBlock->ownerExecutable(), stubCode, structure, prototypeStructure, isDirect);
 
     // Finally patch the jump to slow case back in the hot path to jump here instead.
-    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
+    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
     RepatchBuffer repatchBuffer(m_codeBlock);
-    repatchBuffer.relink(jumpLocation, entryLabel);
+    repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubCode.code()));
 }
 
 void JIT::privateCompileGetByIdChainList(StructureStubInfo* stubInfo, PolymorphicAccessStructureList* prototypeStructures, int currentIndex, Structure* structure, StructureChain* chain, size_t count, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, CallFrame* callFrame)
@@ -883,6 +839,7 @@ void JIT::privateCompileGetByIdChainList(StructureStubInfo* stubInfo, Polymorphi
     ASSERT(protoObject);
     
     bool needsStubLink = false;
+    bool isDirect = false;
     if (slot.cachedPropertyType() == PropertySlot::Getter) {
         needsStubLink = true;
         compileGetDirectOffset(protoObject, regT1, cachedOffset);
@@ -899,11 +856,13 @@ void JIT::privateCompileGetByIdChainList(StructureStubInfo* stubInfo, Polymorphi
         stubCall.addArgument(TrustedImmPtr(const_cast<Identifier*>(&ident)));
         stubCall.addArgument(TrustedImmPtr(stubInfo->callReturnLocation.executableAddress()));
         stubCall.call();
-    } else
+    } else {
+        isDirect = true;
         compileGetDirectOffset(protoObject, regT0, cachedOffset);
+    }
     Jump success = jump();
 
-    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock->executablePool());
+    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock);
     
     if (needsStubLink) {
         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
@@ -913,22 +872,22 @@ void JIT::privateCompileGetByIdChainList(StructureStubInfo* stubInfo, Polymorphi
     }
 
     // Use the patch information to link the failure cases back to the original slow case routine.
-    CodeLocationLabel lastProtoBegin = prototypeStructures->list[currentIndex - 1].stubRoutine;
+    CodeLocationLabel lastProtoBegin = CodeLocationLabel(prototypeStructures->list[currentIndex - 1].stubRoutine.code());
 
     patchBuffer.link(bucketsOfFail, lastProtoBegin);
 
     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
-    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
+    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 
-    CodeLocationLabel entryLabel = patchBuffer.finalizeCodeAddendum();
+    CodeRef stubRoutine = patchBuffer.finalizeCode();
 
     // Track the stub we have created so that it will be deleted later.
-    prototypeStructures->list[currentIndex].set(callFrame->globalData(), m_codeBlock->ownerExecutable(), entryLabel, structure, chain);
+    prototypeStructures->list[currentIndex].set(callFrame->globalData(), m_codeBlock->ownerExecutable(), stubRoutine, structure, chain, isDirect);
 
     // Finally patch the jump to slow case back in the hot path to jump here instead.
-    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
+    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
     RepatchBuffer repatchBuffer(m_codeBlock);
-    repatchBuffer.relink(jumpLocation, entryLabel);
+    repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubRoutine.code()));
 }
 
 void JIT::privateCompileGetByIdChain(StructureStubInfo* stubInfo, Structure* structure, StructureChain* chain, size_t count, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, ReturnAddressPtr returnAddress, CallFrame* callFrame)
@@ -971,7 +930,7 @@ void JIT::privateCompileGetByIdChain(StructureStubInfo* stubInfo, Structure* str
         compileGetDirectOffset(protoObject, regT0, cachedOffset);
     Jump success = jump();
 
-    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock->executablePool());
+    LinkBuffer patchBuffer(*m_globalData, this, m_codeBlock);
 
     if (needsStubLink) {
         for (Vector<CallRecord>::iterator iter = m_calls.begin(); iter != m_calls.end(); ++iter) {
@@ -981,30 +940,175 @@ void JIT::privateCompileGetByIdChain(StructureStubInfo* stubInfo, Structure* str
     }
 
     // Use the patch information to link the failure cases back to the original slow case routine.
-    patchBuffer.link(bucketsOfFail, stubInfo->callReturnLocation.labelAtOffset(-patchOffsetGetByIdSlowCaseCall));
+    patchBuffer.link(bucketsOfFail, stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin));
 
     // On success return back to the hot patch code, at a point it will perform the store to dest for us.
-    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(patchOffsetGetByIdPutResult));
+    patchBuffer.link(success, stubInfo->hotPathBegin.labelAtOffset(stubInfo->patch.baseline.u.get.putResult));
 
     // Track the stub we have created so that it will be deleted later.
-    CodeLocationLabel entryLabel = patchBuffer.finalizeCodeAddendum();
-    stubInfo->stubRoutine = entryLabel;
+    CodeRef stubRoutine = patchBuffer.finalizeCode();
+    stubInfo->stubRoutine = stubRoutine;
 
     // Finally patch the jump to slow case back in the hot path to jump here instead.
-    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(patchOffsetGetByIdBranchToSlowCase);
+    CodeLocationJump jumpLocation = stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck);
     RepatchBuffer repatchBuffer(m_codeBlock);
-    repatchBuffer.relink(jumpLocation, entryLabel);
+    repatchBuffer.relink(jumpLocation, CodeLocationLabel(stubRoutine.code()));
 
     // We don't want to patch more than once - in future go to cti_op_put_by_id_generic.
     repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_proto_list));
 }
 
-/* ------------------------------ END: !ENABLE / ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS) ------------------------------ */
+void JIT::emit_op_get_scoped_var(Instruction* currentInstruction)
+{
+    int skip = currentInstruction[3].u.operand;
+
+    emitGetFromCallFrameHeaderPtr(RegisterFile::ScopeChain, regT0);
+    bool checkTopLevel = m_codeBlock->codeType() == FunctionCode && m_codeBlock->needsFullScopeChain();
+    ASSERT(skip || !checkTopLevel);
+    if (checkTopLevel && skip--) {
+        Jump activationNotCreated;
+        if (checkTopLevel)
+            activationNotCreated = branchTestPtr(Zero, addressFor(m_codeBlock->activationRegister()));
+        loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, next)), regT0);
+        activationNotCreated.link(this);
+    }
+    while (skip--)
+        loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, next)), regT0);
+
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, object)), regT0);
+    loadPtr(Address(regT0, JSVariableObject::offsetOfRegisters()), regT0);
+    loadPtr(Address(regT0, currentInstruction[2].u.operand * sizeof(Register)), regT0);
+    emitValueProfilingSite();
+    emitPutVirtualRegister(currentInstruction[1].u.operand);
+}
+
+void JIT::emit_op_put_scoped_var(Instruction* currentInstruction)
+{
+    int skip = currentInstruction[2].u.operand;
+
+    emitGetVirtualRegister(currentInstruction[3].u.operand, regT0);
+
+    emitGetFromCallFrameHeaderPtr(RegisterFile::ScopeChain, regT1);
+    bool checkTopLevel = m_codeBlock->codeType() == FunctionCode && m_codeBlock->needsFullScopeChain();
+    ASSERT(skip || !checkTopLevel);
+    if (checkTopLevel && skip--) {
+        Jump activationNotCreated;
+        if (checkTopLevel)
+            activationNotCreated = branchTestPtr(Zero, addressFor(m_codeBlock->activationRegister()));
+        loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, next)), regT1);
+        activationNotCreated.link(this);
+    }
+    while (skip--)
+        loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, next)), regT1);
+    loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, object)), regT1);
 
-#endif // !ENABLE(JIT_OPTIMIZE_PROPERTY_ACCESS)
+    emitWriteBarrier(regT1, regT0, regT2, regT3, ShouldFilterImmediates, WriteBarrierForVariableAccess);
+
+    loadPtr(Address(regT1, JSVariableObject::offsetOfRegisters()), regT1);
+    storePtr(regT0, Address(regT1, currentInstruction[1].u.operand * sizeof(Register)));
+}
+
+void JIT::emit_op_get_global_var(Instruction* currentInstruction)
+{
+    JSVariableObject* globalObject = m_codeBlock->globalObject();
+    loadPtr(&globalObject->m_registers, regT0);
+    loadPtr(Address(regT0, currentInstruction[2].u.operand * sizeof(Register)), regT0);
+    emitValueProfilingSite();
+    emitPutVirtualRegister(currentInstruction[1].u.operand);
+}
+
+void JIT::emit_op_put_global_var(Instruction* currentInstruction)
+{
+    JSGlobalObject* globalObject = m_codeBlock->globalObject();
+
+    emitGetVirtualRegister(currentInstruction[2].u.operand, regT0);
+
+    move(TrustedImmPtr(globalObject), regT1);
+    loadPtr(Address(regT1, JSVariableObject::offsetOfRegisters()), regT1);
+    storePtr(regT0, Address(regT1, currentInstruction[1].u.operand * sizeof(Register)));
+    emitWriteBarrier(globalObject, regT0, regT2, ShouldFilterImmediates, WriteBarrierForVariableAccess);
+}
+
+void JIT::resetPatchGetById(RepatchBuffer& repatchBuffer, StructureStubInfo* stubInfo)
+{
+    repatchBuffer.relink(stubInfo->callReturnLocation, cti_op_get_by_id);
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.get.structureToCompare), reinterpret_cast<void*>(-1));
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(stubInfo->patch.baseline.u.get.displacementLabel), 0);
+    repatchBuffer.relink(stubInfo->hotPathBegin.jumpAtOffset(stubInfo->patch.baseline.u.get.structureCheck), stubInfo->callReturnLocation.labelAtOffset(-stubInfo->patch.baseline.u.get.coldPathBegin));
+}
+
+void JIT::resetPatchPutById(RepatchBuffer& repatchBuffer, StructureStubInfo* stubInfo)
+{
+    if (isDirectPutById(stubInfo))
+        repatchBuffer.relink(stubInfo->callReturnLocation, cti_op_put_by_id_direct);
+    else
+        repatchBuffer.relink(stubInfo->callReturnLocation, cti_op_put_by_id);
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.put.structureToCompare), reinterpret_cast<void*>(-1));
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(stubInfo->patch.baseline.u.put.displacementLabel), 0);
+}
 
 #endif // USE(JSVALUE64)
 
+void JIT::emitWriteBarrier(RegisterID owner, RegisterID value, RegisterID scratch, RegisterID scratch2, WriteBarrierMode mode, WriteBarrierUseKind useKind)
+{
+    UNUSED_PARAM(owner);
+    UNUSED_PARAM(scratch);
+    UNUSED_PARAM(scratch2);
+    UNUSED_PARAM(useKind);
+    UNUSED_PARAM(value);
+    UNUSED_PARAM(mode);
+    ASSERT(owner != scratch);
+    ASSERT(owner != scratch2);
+    
+#if ENABLE(WRITE_BARRIER_PROFILING)
+    emitCount(WriteBarrierCounters::jitCounterFor(useKind));
+#endif
+    
+#if ENABLE(GGC)
+    Jump filterCells;
+    if (mode == ShouldFilterImmediates)
+        filterCells = emitJumpIfNotJSCell(value);
+    move(owner, scratch);
+    andPtr(TrustedImm32(static_cast<int32_t>(MarkedBlock::blockMask)), scratch);
+    move(owner, scratch2);
+    // consume additional 8 bits as we're using an approximate filter
+    rshift32(TrustedImm32(MarkedBlock::atomShift + 8), scratch2);
+    andPtr(TrustedImm32(MarkedBlock::atomMask >> 8), scratch2);
+    Jump filter = branchTest8(Zero, BaseIndex(scratch, scratch2, TimesOne, MarkedBlock::offsetOfMarks()));
+    move(owner, scratch2);
+    rshift32(TrustedImm32(MarkedBlock::cardShift), scratch2);
+    andPtr(TrustedImm32(MarkedBlock::cardMask), scratch2);
+    store8(TrustedImm32(1), BaseIndex(scratch, scratch2, TimesOne, MarkedBlock::offsetOfCards()));
+    filter.link(this);
+    if (mode == ShouldFilterImmediates)
+        filterCells.link(this);
+#endif
+}
+
+void JIT::emitWriteBarrier(JSCell* owner, RegisterID value, RegisterID scratch, WriteBarrierMode mode, WriteBarrierUseKind useKind)
+{
+    UNUSED_PARAM(owner);
+    UNUSED_PARAM(scratch);
+    UNUSED_PARAM(useKind);
+    UNUSED_PARAM(value);
+    UNUSED_PARAM(mode);
+    
+#if ENABLE(WRITE_BARRIER_PROFILING)
+    emitCount(WriteBarrierCounters::jitCounterFor(useKind));
+#endif
+    
+#if ENABLE(GGC)
+    Jump filterCells;
+    if (mode == ShouldFilterImmediates)
+        filterCells = emitJumpIfNotJSCell(value);
+    uint8_t* cardAddress = Heap::addressOfCardFor(owner);
+    move(TrustedImmPtr(cardAddress), scratch);
+    store8(TrustedImm32(1), Address(scratch));
+    if (mode == ShouldFilterImmediates)
+        filterCells.link(this);
+#endif
+}
+
 void JIT::testPrototype(JSValue prototype, JumpList& failureCases)
 {
     if (prototype.isNull())
@@ -1015,19 +1119,43 @@ void JIT::testPrototype(JSValue prototype, JumpList& failureCases)
     failureCases.append(branchPtr(NotEqual, Address(regT3, JSCell::structureOffset()), TrustedImmPtr(prototype.asCell()->structure())));
 }
 
-void JIT::patchMethodCallProto(JSGlobalData& globalData, CodeBlock* codeBlock, MethodCallLinkInfo& methodCallLinkInfo, JSObjectWithGlobalObject* callee, Structure* structure, JSObject* proto, ReturnAddressPtr returnAddress)
+void JIT::patchMethodCallProto(JSGlobalData& globalData, CodeBlock* codeBlock, MethodCallLinkInfo& methodCallLinkInfo, StructureStubInfo& stubInfo, JSObject* callee, Structure* structure, JSObject* proto, ReturnAddressPtr returnAddress)
 {
     RepatchBuffer repatchBuffer(codeBlock);
     
-    ASSERT(!methodCallLinkInfo.cachedStructure);
     CodeLocationDataLabelPtr structureLocation = methodCallLinkInfo.cachedStructure.location();
     methodCallLinkInfo.cachedStructure.set(globalData, structureLocation, codeBlock->ownerExecutable(), structure);
     
     Structure* prototypeStructure = proto->structure();
-    methodCallLinkInfo.cachedPrototypeStructure.set(globalData, structureLocation.dataLabelPtrAtOffset(patchOffsetMethodCheckProtoStruct), codeBlock->ownerExecutable(), prototypeStructure);
-    methodCallLinkInfo.cachedPrototype.set(globalData, structureLocation.dataLabelPtrAtOffset(patchOffsetMethodCheckProtoObj), codeBlock->ownerExecutable(), proto);
-    methodCallLinkInfo.cachedFunction.set(globalData, structureLocation.dataLabelPtrAtOffset(patchOffsetMethodCheckPutFunction), codeBlock->ownerExecutable(), callee);
-    repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id));
+    methodCallLinkInfo.cachedPrototypeStructure.set(globalData, structureLocation.dataLabelPtrAtOffset(stubInfo.patch.baseline.methodCheckProtoStructureToCompare), codeBlock->ownerExecutable(), prototypeStructure);
+    methodCallLinkInfo.cachedPrototype.set(globalData, structureLocation.dataLabelPtrAtOffset(stubInfo.patch.baseline.methodCheckProtoObj), codeBlock->ownerExecutable(), proto);
+    methodCallLinkInfo.cachedFunction.set(globalData, structureLocation.dataLabelPtrAtOffset(stubInfo.patch.baseline.methodCheckPutFunction), codeBlock->ownerExecutable(), callee);
+    repatchBuffer.relinkCallerToFunction(returnAddress, FunctionPtr(cti_op_get_by_id_method_check_update));
+}
+
+bool JIT::isDirectPutById(StructureStubInfo* stubInfo)
+{
+    switch (stubInfo->accessType) {
+    case access_put_by_id_transition_normal:
+        return false;
+    case access_put_by_id_transition_direct:
+        return true;
+    case access_put_by_id_replace:
+    case access_put_by_id_generic: {
+        void* oldCall = MacroAssembler::readCallTarget(stubInfo->callReturnLocation).executableAddress();
+        if (oldCall == bitwise_cast<void*>(cti_op_put_by_id_direct)
+            || oldCall == bitwise_cast<void*>(cti_op_put_by_id_direct_generic)
+            || oldCall == bitwise_cast<void*>(cti_op_put_by_id_direct_fail))
+            return true;
+        ASSERT(oldCall == bitwise_cast<void*>(cti_op_put_by_id)
+               || oldCall == bitwise_cast<void*>(cti_op_put_by_id_generic)
+               || oldCall == bitwise_cast<void*>(cti_op_put_by_id_fail));
+        return false;
+    }
+    default:
+        ASSERT_NOT_REACHED();
+        return false;
+    }
 }
 
 } // namespace JSC