webkitgtk-2.4.11webkitgtk-2.4.11

1 files changed, 317 insertions, 456 deletions

diff --git a/Source/JavaScriptCore/jit/JITOpcodes32_64.cpp b/Source/JavaScriptCore/jit/JITOpcodes32_64.cpp
index c326ff3e0..29e8880aa 100644
--- a/Source/JavaScriptCore/jit/JITOpcodes32_64.cpp
+++ b/Source/JavaScriptCore/jit/JITOpcodes32_64.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009, 2012-2016 Apple Inc. All rights reserved.
+ * Copyright (C) 2009, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Patrick Gansterer <paroga@paroga.com>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -32,17 +32,14 @@
 
 #include "CCallHelpers.h"
 #include "Debugger.h"
-#include "Exception.h"
 #include "JITInlines.h"
 #include "JSArray.h"
 #include "JSCell.h"
-#include "JSEnvironmentRecord.h"
 #include "JSFunction.h"
-#include "JSPropertyNameEnumerator.h"
+#include "JSPropertyNameIterator.h"
+#include "JSVariableObject.h"
 #include "LinkBuffer.h"
-#include "MaxFrameExtentForSlowPathCall.h"
 #include "SlowPathCall.h"
-#include "TypeProfilerLog.h"
 #include "VirtualRegister.h"
 
 namespace JSC {
@@ -51,24 +48,41 @@ JIT::CodeRef JIT::privateCompileCTINativeCall(VM* vm, NativeFunction func)
 {
     Call nativeCall;
 
-    emitFunctionPrologue();
-    emitPutToCallFrameHeader(0, JSStack::CodeBlock);
+    emitPutImmediateToCallFrameHeader(0, JSStack::CodeBlock);
     storePtr(callFrameRegister, &m_vm->topCallFrame);
 
 #if CPU(X86)
+    // Load caller frame's scope chain into this callframe so that whatever we call can
+    // get to its global data.
+    emitGetCallerFrameFromCallFrameHeaderPtr(regT0);
+    emitGetFromCallFrameHeaderPtr(JSStack::ScopeChain, regT1, regT0);
+    emitPutCellToCallFrameHeader(regT1, JSStack::ScopeChain);
+
+    peek(regT1);
+    emitPutReturnPCToCallFrameHeader(regT1);
+
     // Calling convention:      f(ecx, edx, ...);
     // Host function signature: f(ExecState*);
     move(callFrameRegister, X86Registers::ecx);
 
-    subPtr(TrustedImm32(8), stackPointerRegister); // Align stack for call.
-    storePtr(X86Registers::ecx, Address(stackPointerRegister));
+    subPtr(TrustedImm32(16 - sizeof(void*)), stackPointerRegister); // Align stack after call.
+
+    move(regT0, callFrameRegister); // Eagerly restore caller frame register to avoid loading from stack.
 
     // call the function
     nativeCall = call();
 
-    addPtr(TrustedImm32(8), stackPointerRegister);
+    addPtr(TrustedImm32(16 - sizeof(void*)), stackPointerRegister);
 
 #elif CPU(ARM) || CPU(SH4) || CPU(MIPS)
+    // Load caller frame's scope chain into this callframe so that whatever we call can get to its global data.
+    emitGetCallerFrameFromCallFrameHeaderPtr(regT2);
+    emitGetFromCallFrameHeaderPtr(JSStack::ScopeChain, regT1, regT2);
+    emitPutCellToCallFrameHeader(regT1, JSStack::ScopeChain);
+
+    preserveReturnAddressAfterCall(regT3); // Callee preserved
+    emitPutReturnPCToCallFrameHeader(regT3);
+
 #if CPU(MIPS)
     // Allocate stack space for (unused) 16 bytes (8-byte aligned) for 4 arguments.
     subPtr(TrustedImm32(16), stackPointerRegister);
@@ -79,6 +93,7 @@ JIT::CodeRef JIT::privateCompileCTINativeCall(VM* vm, NativeFunction func)
     move(callFrameRegister, argumentGPR0);
 
     emitGetFromCallFrameHeaderPtr(JSStack::Callee, argumentGPR1);
+    move(regT2, callFrameRegister); // Eagerly restore caller frame register to avoid loading from stack.
     loadPtr(Address(argumentGPR1, OBJECT_OFFSETOF(JSFunction, m_executable)), regT2);
 
     // call the function
@@ -92,25 +107,28 @@ JIT::CodeRef JIT::privateCompileCTINativeCall(VM* vm, NativeFunction func)
     restoreReturnAddressBeforeReturn(regT3);
 #else
 #error "JIT not supported on this platform."
-    abortWithReason(JITNotSupported);
+    breakpoint();
 #endif // CPU(X86)
 
     // Check for an exception
-    Jump sawException = branch32(NotEqual, AbsoluteAddress(vm->addressOfException()), TrustedImm32(0));
+    Jump sawException = branch32(NotEqual, AbsoluteAddress(reinterpret_cast<char*>(vm->addressOfException()) + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), TrustedImm32(JSValue::EmptyValueTag)); 
 
-    emitFunctionEpilogue();
     // Return.
     ret();
 
     // Handle an exception
     sawException.link(this);
 
+    // Grab the return address.
+    preserveReturnAddressAfterCall(regT1);
+
+    move(TrustedImmPtr(&vm->exceptionLocation), regT2);
+    storePtr(regT1, regT2);
     storePtr(callFrameRegister, &m_vm->topCallFrame);
 
 #if CPU(X86)
-    addPtr(TrustedImm32(-4), stackPointerRegister);
-    move(callFrameRegister, X86Registers::ecx);
-    push(X86Registers::ecx);
+    addPtr(TrustedImm32(-12), stackPointerRegister);
+    push(callFrameRegister);
 #else
     move(callFrameRegister, argumentGPR0);
 #endif
@@ -118,13 +136,13 @@ JIT::CodeRef JIT::privateCompileCTINativeCall(VM* vm, NativeFunction func)
     call(regT3);
 
 #if CPU(X86)
-    addPtr(TrustedImm32(8), stackPointerRegister);
+    addPtr(TrustedImm32(16), stackPointerRegister);
 #endif
 
     jumpToExceptionHandler();
 
     // All trampolines constructed! copy the code, link up calls, and set the pointers on the Machine object.
-    LinkBuffer patchBuffer(*m_vm, *this, GLOBAL_THUNK_ID);
+    LinkBuffer patchBuffer(*m_vm, this, GLOBAL_THUNK_ID);
 
     patchBuffer.link(nativeCall, FunctionPtr(func));
     return FINALIZE_CODE(patchBuffer, ("JIT CTI native call"));
@@ -143,12 +161,21 @@ void JIT::emit_op_mov(Instruction* currentInstruction)
     }
 }
 
+void JIT::emit_op_captured_mov(Instruction* currentInstruction)
+{
+    int dst = currentInstruction[1].u.operand;
+    int src = currentInstruction[2].u.operand;
+
+    emitLoad(src, regT1, regT0);
+    emitNotifyWrite(regT1, regT0, regT2, currentInstruction[3].u.watchpointSet);
+    emitStore(dst, regT1, regT0);
+}
+
 void JIT::emit_op_end(Instruction* currentInstruction)
 {
     ASSERT(returnValueGPR != callFrameRegister);
-    emitLoad(currentInstruction[1].u.operand, regT1, returnValueGPR);
-    emitRestoreCalleeSaves();
-    emitFunctionEpilogue();
+    emitLoad(currentInstruction[1].u.operand, regT1, regT0);
+    restoreReturnAddressBeforeReturn(Address(callFrameRegister, CallFrame::returnPCOffset()));
     ret();
 }
 
@@ -164,9 +191,9 @@ void JIT::emit_op_new_object(Instruction* currentInstruction)
     size_t allocationSize = JSFinalObject::allocationSize(structure->inlineCapacity());
     MarkedAllocator* allocator = &m_vm->heap.allocatorForObjectWithoutDestructor(allocationSize);
 
-    RegisterID resultReg = returnValueGPR;
+    RegisterID resultReg = regT0;
     RegisterID allocatorReg = regT1;
-    RegisterID scratchReg = regT3;
+    RegisterID scratchReg = regT2;
 
     move(TrustedImmPtr(allocator), allocatorReg);
     emitAllocateJSObject(allocatorReg, TrustedImmPtr(structure), resultReg, scratchReg);
@@ -182,31 +209,18 @@ void JIT::emitSlow_op_new_object(Instruction* currentInstruction, Vector<SlowCas
     emitStoreCell(dst, returnValueGPR);
 }
 
-void JIT::emit_op_overrides_has_instance(Instruction* currentInstruction)
+void JIT::emit_op_check_has_instance(Instruction* currentInstruction)
 {
-    int dst = currentInstruction[1].u.operand;
-    int constructor = currentInstruction[2].u.operand;
-    int hasInstanceValue = currentInstruction[3].u.operand;
-
-    emitLoadPayload(hasInstanceValue, regT0);
-    // We don't jump if we know what Symbol.hasInstance would do.
-    Jump hasInstanceValueNotCell = emitJumpIfNotJSCell(hasInstanceValue);
-    Jump customhasInstanceValue = branchPtr(NotEqual, regT0, TrustedImmPtr(m_codeBlock->globalObject()->functionProtoHasInstanceSymbolFunction()));
-
-    // We know that constructor is an object from the way bytecode is emitted for instanceof expressions.
-    emitLoadPayload(constructor, regT0);
-
-    // Check that constructor 'ImplementsDefaultHasInstance' i.e. the object is not a C-API user nor a bound function.
-    test8(Zero, Address(regT0, JSCell::typeInfoFlagsOffset()), TrustedImm32(ImplementsDefaultHasInstance), regT0);
-    Jump done = jump();
+    int baseVal = currentInstruction[3].u.operand;
 
-    hasInstanceValueNotCell.link(this);
-    customhasInstanceValue.link(this);
-    move(TrustedImm32(1), regT0);
-
-    done.link(this);
-    emitStoreBool(dst, regT0);
+    emitLoadPayload(baseVal, regT0);
 
+    // Check that baseVal is a cell.
+    emitJumpSlowCaseIfNotJSCell(baseVal);
+    
+    // Check that baseVal 'ImplementsHasInstance'.
+    loadPtr(Address(regT0, JSCell::structureOffset()), regT0);
+    addSlowCase(branchTest8(Zero, Address(regT0, Structure::typeInfoFlagsOffset()), TrustedImm32(ImplementsDefaultHasInstance)));
 }
 
 void JIT::emit_op_instanceof(Instruction* currentInstruction)
@@ -220,12 +234,13 @@ void JIT::emit_op_instanceof(Instruction* currentInstruction)
     emitLoadPayload(value, regT2);
     emitLoadPayload(proto, regT1);
 
-    // Check that proto are cells. baseVal must be a cell - this is checked by the get_by_id for Symbol.hasInstance.
+    // Check that proto are cells.  baseVal must be a cell - this is checked by op_check_has_instance.
     emitJumpSlowCaseIfNotJSCell(value);
     emitJumpSlowCaseIfNotJSCell(proto);
     
     // Check that prototype is an object
-    addSlowCase(emitJumpIfCellNotObject(regT1));
+    loadPtr(Address(regT1, JSCell::structureOffset()), regT3);
+    addSlowCase(emitJumpIfNotObject(regT3));
 
     // Optimistically load the result true, and start looping.
     // Initially, regT1 still contains proto and regT2 still contains value.
@@ -235,7 +250,7 @@ void JIT::emit_op_instanceof(Instruction* currentInstruction)
 
     // Load the prototype of the cell in regT2.  If this is equal to regT1 - WIN!
     // Otherwise, check if we've hit null - if we have then drop out of the loop, if not go again.
-    loadPtr(Address(regT2, JSCell::structureIDOffset()), regT2);
+    loadPtr(Address(regT2, JSCell::structureOffset()), regT2);
     load32(Address(regT2, Structure::prototypeOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT2);
     Jump isInstance = branchPtr(Equal, regT2, regT1);
     branchTest32(NonZero, regT2).linkTo(loop, this);
@@ -248,41 +263,35 @@ void JIT::emit_op_instanceof(Instruction* currentInstruction)
     emitStoreBool(dst, regT0);
 }
 
-void JIT::emit_op_instanceof_custom(Instruction*)
-{
-    // This always goes to slow path since we expect it to be rare.
-    addSlowCase(jump());
-}
-
-void JIT::emitSlow_op_instanceof(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+void JIT::emitSlow_op_check_has_instance(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
     int dst = currentInstruction[1].u.operand;
     int value = currentInstruction[2].u.operand;
-    int proto = currentInstruction[3].u.operand;
+    int baseVal = currentInstruction[3].u.operand;
 
-    linkSlowCaseIfNotJSCell(iter, value);
-    linkSlowCaseIfNotJSCell(iter, proto);
+    linkSlowCaseIfNotJSCell(iter, baseVal);
     linkSlowCase(iter);
 
     emitLoad(value, regT1, regT0);
-    emitLoad(proto, regT3, regT2);
-    callOperation(operationInstanceOf, dst, regT1, regT0, regT3, regT2);
+    emitLoad(baseVal, regT3, regT2);
+    callOperation(operationCheckHasInstance, dst, regT1, regT0, regT3, regT2);
+
+    emitJumpSlowToHot(jump(), currentInstruction[4].u.operand);
 }
 
-void JIT::emitSlow_op_instanceof_custom(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+void JIT::emitSlow_op_instanceof(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
     int dst = currentInstruction[1].u.operand;
     int value = currentInstruction[2].u.operand;
-    int constructor = currentInstruction[3].u.operand;
-    int hasInstanceValue = currentInstruction[4].u.operand;
+    int proto = currentInstruction[3].u.operand;
 
+    linkSlowCaseIfNotJSCell(iter, value);
+    linkSlowCaseIfNotJSCell(iter, proto);
     linkSlowCase(iter);
 
     emitLoad(value, regT1, regT0);
-    emitLoadPayload(constructor, regT2);
-    emitLoad(hasInstanceValue, regT4, regT3);
-    callOperation(operationInstanceOfCustom, regT1, regT0, regT2, regT4, regT3);
-    emitStoreBool(dst, returnValueGPR);
+    emitLoad(proto, regT3, regT2);
+    callOperation(operationInstanceOf, dst, regT1, regT0, regT3, regT2);
 }
 
 void JIT::emit_op_is_undefined(Instruction* currentInstruction)
@@ -297,12 +306,12 @@ void JIT::emit_op_is_undefined(Instruction* currentInstruction)
     Jump done = jump();
     
     isCell.link(this);
-    Jump isMasqueradesAsUndefined = branchTest8(NonZero, Address(regT0, JSCell::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined));
+    loadPtr(Address(regT0, JSCell::structureOffset()), regT1);
+    Jump isMasqueradesAsUndefined = branchTest8(NonZero, Address(regT1, Structure::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined));
     move(TrustedImm32(0), regT0);
     Jump notMasqueradesAsUndefined = jump();
     
     isMasqueradesAsUndefined.link(this);
-    loadPtr(Address(regT0, JSCell::structureIDOffset()), regT1);
     move(TrustedImmPtr(m_codeBlock->globalObject()), regT0);
     loadPtr(Address(regT1, Structure::globalObjectOffset()), regT1);
     compare32(Equal, regT0, regT1, regT0);
@@ -341,7 +350,8 @@ void JIT::emit_op_is_string(Instruction* currentInstruction)
     emitLoad(value, regT1, regT0);
     Jump isNotCell = branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag));
     
-    compare8(Equal, Address(regT0, JSCell::typeInfoTypeOffset()), TrustedImm32(StringType), regT0);
+    loadPtr(Address(regT0, JSCell::structureOffset()), regT1);
+    compare8(Equal, Address(regT1, Structure::typeInfoTypeOffset()), TrustedImm32(StringType), regT0);
     Jump done = jump();
     
     isNotCell.link(this);
@@ -351,22 +361,25 @@ void JIT::emit_op_is_string(Instruction* currentInstruction)
     emitStoreBool(dst, regT0);
 }
 
-void JIT::emit_op_is_object(Instruction* currentInstruction)
+void JIT::emit_op_tear_off_activation(Instruction* currentInstruction)
 {
-    int dst = currentInstruction[1].u.operand;
-    int value = currentInstruction[2].u.operand;
-
-    emitLoad(value, regT1, regT0);
-    Jump isNotCell = branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag));
-
-    compare8(AboveOrEqual, Address(regT0, JSCell::typeInfoTypeOffset()), TrustedImm32(ObjectType), regT0);
-    Jump done = jump();
+    int activation = currentInstruction[1].u.operand;
+    Jump activationNotCreated = branch32(Equal, tagFor(activation), TrustedImm32(JSValue::EmptyValueTag));
+    emitLoadPayload(activation, regT0);
+    callOperation(operationTearOffActivation, regT0);
+    activationNotCreated.link(this);
+}
 
-    isNotCell.link(this);
-    move(TrustedImm32(0), regT0);
+void JIT::emit_op_tear_off_arguments(Instruction* currentInstruction)
+{
+    VirtualRegister arguments = VirtualRegister(currentInstruction[1].u.operand);
+    int activation = currentInstruction[2].u.operand;
 
-    done.link(this);
-    emitStoreBool(dst, regT0);
+    Jump argsNotCreated = branch32(Equal, tagFor(unmodifiedArgumentsRegister(arguments).offset()), TrustedImm32(JSValue::EmptyValueTag));
+    emitLoadPayload(unmodifiedArgumentsRegister(VirtualRegister(arguments)).offset(), regT0);
+    emitLoadPayload(activation, regT1);
+    callOperation(operationTearOffArguments, regT0, regT1);
+    argsNotCreated.link(this);
 }
 
 void JIT::emit_op_to_primitive(Instruction* currentInstruction)
@@ -377,7 +390,7 @@ void JIT::emit_op_to_primitive(Instruction* currentInstruction)
     emitLoad(src, regT1, regT0);
 
     Jump isImm = branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag));
-    addSlowCase(emitJumpIfCellObject(regT0));
+    addSlowCase(branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
     isImm.link(this);
 
     if (dst != src)
@@ -497,8 +510,9 @@ void JIT::emit_op_jeq_null(Instruction* currentInstruction)
 
     Jump isImmediate = branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag));
 
-    Jump isNotMasqueradesAsUndefined = branchTest8(Zero, Address(regT0, JSCell::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined));
-    loadPtr(Address(regT0, JSCell::structureIDOffset()), regT2);
+    // First, handle JSCell cases - check MasqueradesAsUndefined bit on the structure.
+    loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
+    Jump isNotMasqueradesAsUndefined = branchTest8(Zero, Address(regT2, Structure::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined));
     move(TrustedImmPtr(m_codeBlock->globalObject()), regT0);
     addJump(branchPtr(Equal, Address(regT2, Structure::globalObjectOffset()), regT0), target);
     Jump masqueradesGlobalObjectIsForeign = jump();
@@ -522,8 +536,9 @@ void JIT::emit_op_jneq_null(Instruction* currentInstruction)
 
     Jump isImmediate = branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag));
 
-    addJump(branchTest8(Zero, Address(regT0, JSCell::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined)), target);
-    loadPtr(Address(regT0, JSCell::structureIDOffset()), regT2);
+    // First, handle JSCell cases - check MasqueradesAsUndefined bit on the structure.
+    loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
+    addJump(branchTest8(Zero, Address(regT2, Structure::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined)), target);
     move(TrustedImmPtr(m_codeBlock->globalObject()), regT0);
     addJump(branchPtr(NotEqual, Address(regT2, Structure::globalObjectOffset()), regT0), target);
     Jump wasNotImmediate = jump();
@@ -577,8 +592,8 @@ void JIT::emitSlow_op_eq(Instruction* currentInstruction, Vector<SlowCaseEntry>:
     genericCase.append(getSlowCase(iter)); // tags not equal
 
     linkSlowCase(iter); // tags equal and JSCell
-    genericCase.append(branchPtr(NotEqual, Address(regT0, JSCell::structureIDOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
-    genericCase.append(branchPtr(NotEqual, Address(regT2, JSCell::structureIDOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
+    genericCase.append(branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
+    genericCase.append(branchPtr(NotEqual, Address(regT2, JSCell::structureOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
 
     // String case.
     callOperation(operationCompareStringEq, regT0, regT2);
@@ -621,8 +636,8 @@ void JIT::emitSlow_op_neq(Instruction* currentInstruction, Vector<SlowCaseEntry>
     genericCase.append(getSlowCase(iter)); // tags not equal
 
     linkSlowCase(iter); // tags equal and JSCell
-    genericCase.append(branchPtr(NotEqual, Address(regT0, JSCell::structureIDOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
-    genericCase.append(branchPtr(NotEqual, Address(regT2, JSCell::structureIDOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
+    genericCase.append(branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
+    genericCase.append(branchPtr(NotEqual, Address(regT2, JSCell::structureOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
 
     // String case.
     callOperation(operationCompareStringEq, regT0, regT2);
@@ -650,12 +665,12 @@ void JIT::compileOpStrictEq(Instruction* currentInstruction, CompileOpStrictEqTy
     addSlowCase(branch32(NotEqual, regT1, regT3));
     addSlowCase(branch32(Below, regT1, TrustedImm32(JSValue::LowestTag)));
 
-    // Jump to a slow case if both are strings or symbols (non object).
+    // Jump to a slow case if both are strings.
     Jump notCell = branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag));
-    Jump firstIsObject = emitJumpIfCellObject(regT0);
-    addSlowCase(emitJumpIfCellNotObject(regT2));
+    Jump firstNotString = branchPtr(NotEqual, Address(regT0, JSCell::structureOffset()), TrustedImmPtr(m_vm->stringStructure.get()));
+    addSlowCase(branchPtr(Equal, Address(regT2, JSCell::structureOffset()), TrustedImmPtr(m_vm->stringStructure.get())));
     notCell.link(this);
-    firstIsObject.link(this);
+    firstNotString.link(this);
 
     // Simply compare the payloads.
     if (type == OpStrictEq)
@@ -704,12 +719,12 @@ void JIT::emit_op_eq_null(Instruction* currentInstruction)
     emitLoad(src, regT1, regT0);
     Jump isImmediate = branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag));
 
-    Jump isMasqueradesAsUndefined = branchTest8(NonZero, Address(regT0, JSCell::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined));
+    loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
+    Jump isMasqueradesAsUndefined = branchTest8(NonZero, Address(regT2, Structure::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined));
     move(TrustedImm32(0), regT1);
     Jump wasNotMasqueradesAsUndefined = jump();
 
     isMasqueradesAsUndefined.link(this);
-    loadPtr(Address(regT0, JSCell::structureIDOffset()), regT2);
     move(TrustedImmPtr(m_codeBlock->globalObject()), regT0);
     loadPtr(Address(regT2, Structure::globalObjectOffset()), regT2);
     compare32(Equal, regT0, regT2, regT1);
@@ -735,12 +750,12 @@ void JIT::emit_op_neq_null(Instruction* currentInstruction)
     emitLoad(src, regT1, regT0);
     Jump isImmediate = branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag));
 
-    Jump isMasqueradesAsUndefined = branchTest8(NonZero, Address(regT0, JSCell::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined));
+    loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
+    Jump isMasqueradesAsUndefined = branchTest8(NonZero, Address(regT2, Structure::typeInfoFlagsOffset()), TrustedImm32(MasqueradesAsUndefined));
     move(TrustedImm32(1), regT1);
     Jump wasNotMasqueradesAsUndefined = jump();
 
     isMasqueradesAsUndefined.link(this);
-    loadPtr(Address(regT0, JSCell::structureIDOffset()), regT2);
     move(TrustedImmPtr(m_codeBlock->globalObject()), regT0);
     loadPtr(Address(regT2, Structure::globalObjectOffset()), regT2);
     compare32(NotEqual, regT0, regT2, regT1);
@@ -761,116 +776,165 @@ void JIT::emit_op_neq_null(Instruction* currentInstruction)
 void JIT::emit_op_throw(Instruction* currentInstruction)
 {
     ASSERT(regT0 == returnValueGPR);
-    copyCalleeSavesToVMCalleeSavesBuffer();
     emitLoad(currentInstruction[1].u.operand, regT1, regT0);
     callOperationNoExceptionCheck(operationThrow, regT1, regT0);
     jumpToExceptionHandler();
 }
 
-void JIT::emit_op_push_with_scope(Instruction* currentInstruction)
+void JIT::emit_op_get_pnames(Instruction* currentInstruction)
 {
-    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_push_with_scope);
-    slowPathCall.call();
+    int dst = currentInstruction[1].u.operand;
+    int base = currentInstruction[2].u.operand;
+    int i = currentInstruction[3].u.operand;
+    int size = currentInstruction[4].u.operand;
+    int breakTarget = currentInstruction[5].u.operand;
+
+    JumpList isNotObject;
+
+    emitLoad(base, regT1, regT0);
+    if (!m_codeBlock->isKnownNotImmediate(base))
+        isNotObject.append(branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag)));
+    if (VirtualRegister(base) != m_codeBlock->thisRegister() || m_codeBlock->isStrictMode()) {
+        loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
+        isNotObject.append(emitJumpIfNotObject(regT2));
+    }
+
+    // We could inline the case where you have a valid cache, but
+    // this call doesn't seem to be hot.
+    Label isObject(this);
+    callOperation(operationGetPNames, regT0);
+    emitStoreCell(dst, returnValueGPR);
+    load32(Address(regT0, OBJECT_OFFSETOF(JSPropertyNameIterator, m_jsStringsSize)), regT3);
+    store32(TrustedImm32(Int32Tag), intTagFor(i));
+    store32(TrustedImm32(0), intPayloadFor(i));
+    store32(TrustedImm32(Int32Tag), intTagFor(size));
+    store32(regT3, payloadFor(size));
+    Jump end = jump();
+
+    isNotObject.link(this);
+    addJump(branch32(Equal, regT1, TrustedImm32(JSValue::NullTag)), breakTarget);
+    addJump(branch32(Equal, regT1, TrustedImm32(JSValue::UndefinedTag)), breakTarget);
+    callOperation(operationToObject, base, regT1, regT0);
+    jump().linkTo(isObject, this);
+
+    end.link(this);
 }
 
-void JIT::emit_op_to_number(Instruction* currentInstruction)
+void JIT::emit_op_next_pname(Instruction* currentInstruction)
 {
     int dst = currentInstruction[1].u.operand;
-    int src = currentInstruction[2].u.operand;
+    int base = currentInstruction[2].u.operand;
+    int i = currentInstruction[3].u.operand;
+    int size = currentInstruction[4].u.operand;
+    int it = currentInstruction[5].u.operand;
+    int target = currentInstruction[6].u.operand;
 
-    emitLoad(src, regT1, regT0);
+    JumpList callHasProperty;
 
-    Jump isInt32 = branch32(Equal, regT1, TrustedImm32(JSValue::Int32Tag));
-    addSlowCase(branch32(AboveOrEqual, regT1, TrustedImm32(JSValue::LowestTag)));
-    isInt32.link(this);
+    Label begin(this);
+    load32(intPayloadFor(i), regT0);
+    Jump end = branch32(Equal, regT0, intPayloadFor(size));
 
-    if (src != dst)
-        emitStore(dst, regT1, regT0);
+    // Grab key @ i
+    loadPtr(payloadFor(it), regT1);
+    loadPtr(Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_jsStrings)), regT2);
+    load32(BaseIndex(regT2, regT0, TimesEight), regT2);
+    store32(TrustedImm32(JSValue::CellTag), tagFor(dst));
+    store32(regT2, payloadFor(dst));
+
+    // Increment i
+    add32(TrustedImm32(1), regT0);
+    store32(regT0, intPayloadFor(i));
+
+    // Verify that i is valid:
+    loadPtr(payloadFor(base), regT0);
+
+    // Test base's structure
+    loadPtr(Address(regT0, JSCell::structureOffset()), regT2);
+    callHasProperty.append(branchPtr(NotEqual, regT2, Address(Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_cachedStructure)))));
+
+    // Test base's prototype chain
+    loadPtr(Address(Address(regT1, OBJECT_OFFSETOF(JSPropertyNameIterator, m_cachedPrototypeChain))), regT3);
+    loadPtr(Address(regT3, OBJECT_OFFSETOF(StructureChain, m_vector)), regT3);
+    addJump(branchTestPtr(Zero, Address(regT3)), target);
+
+    Label checkPrototype(this);
+    callHasProperty.append(branch32(Equal, Address(regT2, Structure::prototypeOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), TrustedImm32(JSValue::NullTag)));
+    loadPtr(Address(regT2, Structure::prototypeOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT2);
+    loadPtr(Address(regT2, JSCell::structureOffset()), regT2);
+    callHasProperty.append(branchPtr(NotEqual, regT2, Address(regT3)));
+    addPtr(TrustedImm32(sizeof(Structure*)), regT3);
+    branchTestPtr(NonZero, Address(regT3)).linkTo(checkPrototype, this);
+
+    // Continue loop.
+    addJump(jump(), target);
+
+    // Slow case: Ask the object if i is valid.
+    callHasProperty.link(this);
+    loadPtr(addressFor(dst), regT1);
+    callOperation(operationHasProperty, regT0, regT1);
+
+    // Test for valid key.
+    addJump(branchTest32(NonZero, regT0), target);
+    jump().linkTo(begin, this);
+
+    // End of loop.
+    end.link(this);
 }
 
-void JIT::emitSlow_op_to_number(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+void JIT::emit_op_push_with_scope(Instruction* currentInstruction)
 {
-    linkSlowCase(iter);
+    emitLoad(currentInstruction[1].u.operand, regT1, regT0);
+    callOperation(operationPushWithScope, regT1, regT0);
+}
 
-    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_to_number);
-    slowPathCall.call();
+void JIT::emit_op_pop_scope(Instruction*)
+{
+    callOperation(operationPopScope);
 }
 
-void JIT::emit_op_to_string(Instruction* currentInstruction)
+void JIT::emit_op_to_number(Instruction* currentInstruction)
 {
     int dst = currentInstruction[1].u.operand;
     int src = currentInstruction[2].u.operand;
 
     emitLoad(src, regT1, regT0);
 
-    addSlowCase(branch32(NotEqual, regT1, TrustedImm32(JSValue::CellTag)));
-    addSlowCase(branch8(NotEqual, Address(regT0, JSCell::typeInfoTypeOffset()), TrustedImm32(StringType)));
+    Jump isInt32 = branch32(Equal, regT1, TrustedImm32(JSValue::Int32Tag));
+    addSlowCase(branch32(AboveOrEqual, regT1, TrustedImm32(JSValue::LowestTag)));
+    isInt32.link(this);
 
     if (src != dst)
         emitStore(dst, regT1, regT0);
 }
 
-void JIT::emitSlow_op_to_string(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+void JIT::emitSlow_op_to_number(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    linkSlowCase(iter); // Not JSCell.
-    linkSlowCase(iter); // Not JSString.
+    linkSlowCase(iter);
 
-    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_to_string);
+    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_to_number);
     slowPathCall.call();
 }
 
-void JIT::emit_op_catch(Instruction* currentInstruction)
+void JIT::emit_op_push_name_scope(Instruction* currentInstruction)
 {
-    restoreCalleeSavesFromVMCalleeSavesBuffer();
+    emitLoad(currentInstruction[2].u.operand, regT1, regT0);
+    callOperation(operationPushNameScope, &m_codeBlock->identifier(currentInstruction[1].u.operand), regT1, regT0, currentInstruction[3].u.operand);
+}
 
+void JIT::emit_op_catch(Instruction* currentInstruction)
+{
     move(TrustedImmPtr(m_vm), regT3);
     // operationThrow returns the callFrame for the handler.
-    load32(Address(regT3, VM::callFrameForCatchOffset()), callFrameRegister);
-    storePtr(TrustedImmPtr(nullptr), Address(regT3, VM::callFrameForCatchOffset()));
-
-    addPtr(TrustedImm32(stackPointerOffsetFor(codeBlock()) * sizeof(Register)), callFrameRegister, stackPointerRegister);
-
-    callOperationNoExceptionCheck(operationCheckIfExceptionIsUncatchableAndNotifyProfiler);
-    Jump isCatchableException = branchTest32(Zero, returnValueGPR);
-    jumpToExceptionHandler();
-    isCatchableException.link(this);
-
-    move(TrustedImmPtr(m_vm), regT3);
-
+    load32(Address(regT3, VM::callFrameForThrowOffset()), callFrameRegister);
     // Now store the exception returned by operationThrow.
-    load32(Address(regT3, VM::exceptionOffset()), regT2);
-    move(TrustedImm32(JSValue::CellTag), regT1);
-
-    store32(TrustedImm32(0), Address(regT3, VM::exceptionOffset()));
+    load32(Address(regT3, VM::exceptionOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
+    load32(Address(regT3, VM::exceptionOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
+    store32(TrustedImm32(JSValue().payload()), Address(regT3, VM::exceptionOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.payload)));
+    store32(TrustedImm32(JSValue().tag()), Address(regT3, VM::exceptionOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.tag)));
 
     unsigned exception = currentInstruction[1].u.operand;
-    emitStore(exception, regT1, regT2);
-
-    load32(Address(regT2, Exception::valueOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
-    load32(Address(regT2, Exception::valueOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
-
-    unsigned thrownValue = currentInstruction[2].u.operand;
-    emitStore(thrownValue, regT1, regT0);
-}
-
-void JIT::emit_op_assert(Instruction* currentInstruction)
-{
-    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_assert);
-    slowPathCall.call();
-}
-
-void JIT::emit_op_create_lexical_environment(Instruction* currentInstruction)
-{
-    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_create_lexical_environment);
-    slowPathCall.call();
-}
-
-void JIT::emit_op_get_parent_scope(Instruction* currentInstruction)
-{
-    int currentScope = currentInstruction[2].u.operand;
-    emitLoadPayload(currentScope, regT0);
-    loadPtr(Address(regT0, JSScope::offsetOfNext()), regT0);
-    emitStoreCell(currentInstruction[1].u.operand, regT0);
+    emitStore(exception, regT1, regT0);
 }
 
 void JIT::emit_op_switch_imm(Instruction* currentInstruction)
@@ -882,7 +946,7 @@ void JIT::emit_op_switch_imm(Instruction* currentInstruction)
     // create jump table for switch destinations, track this switch statement.
     SimpleJumpTable* jumpTable = &m_codeBlock->switchJumpTable(tableIndex);
     m_switches.append(SwitchRecord(jumpTable, m_bytecodeOffset, defaultOffset, SwitchRecord::Immediate));
-    jumpTable->ensureCTITable();
+    jumpTable->ctiOffsets.grow(jumpTable->branchOffsets.size());
 
     emitLoad(scrutinee, regT1, regT0);
     callOperation(operationSwitchImmWithUnknownKeyType, regT1, regT0, tableIndex);
@@ -898,7 +962,7 @@ void JIT::emit_op_switch_char(Instruction* currentInstruction)
     // create jump table for switch destinations, track this switch statement.
     SimpleJumpTable* jumpTable = &m_codeBlock->switchJumpTable(tableIndex);
     m_switches.append(SwitchRecord(jumpTable, m_bytecodeOffset, defaultOffset, SwitchRecord::Character));
-    jumpTable->ensureCTITable();
+    jumpTable->ctiOffsets.grow(jumpTable->branchOffsets.size());
 
     emitLoad(scrutinee, regT1, regT0);
     callOperation(operationSwitchCharWithUnknownKeyType, regT1, regT0, tableIndex);
@@ -949,48 +1013,77 @@ void JIT::emit_op_enter(Instruction* currentInstruction)
     slowPathCall.call();
 }
 
-void JIT::emit_op_get_scope(Instruction* currentInstruction)
+void JIT::emit_op_create_activation(Instruction* currentInstruction)
+{
+    int activation = currentInstruction[1].u.operand;
+    
+    Jump activationCreated = branch32(NotEqual, tagFor(activation), TrustedImm32(JSValue::EmptyValueTag));
+    callOperation(operationCreateActivation, 0);
+    emitStoreCell(activation, returnValueGPR);
+    activationCreated.link(this);
+}
+
+void JIT::emit_op_create_arguments(Instruction* currentInstruction)
+{
+    int dst = currentInstruction[1].u.operand;
+
+    Jump argsCreated = branch32(NotEqual, tagFor(dst), TrustedImm32(JSValue::EmptyValueTag));
+    callOperation(operationCreateArguments);
+    emitStoreCell(dst, returnValueGPR);
+    emitStoreCell(unmodifiedArgumentsRegister(VirtualRegister(dst)).offset(), returnValueGPR);
+    argsCreated.link(this);
+}
+
+void JIT::emit_op_init_lazy_reg(Instruction* currentInstruction)
 {
     int dst = currentInstruction[1].u.operand;
+
+    emitStore(dst, JSValue());
+}
+
+void JIT::emit_op_get_callee(Instruction* currentInstruction)
+{
+    int result = currentInstruction[1].u.operand;
+    WriteBarrierBase<JSCell>* cachedFunction = &currentInstruction[2].u.jsCell;
     emitGetFromCallFrameHeaderPtr(JSStack::Callee, regT0);
-    loadPtr(Address(regT0, JSFunction::offsetOfScopeChain()), regT0);
-    emitStoreCell(dst, regT0);
+
+    loadPtr(cachedFunction, regT2);
+    addSlowCase(branchPtr(NotEqual, regT0, regT2));
+
+    move(TrustedImm32(JSValue::CellTag), regT1);
+    emitStore(result, regT1, regT0);
+}
+
+void JIT::emitSlow_op_get_callee(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+{
+    linkSlowCase(iter);
+
+    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_get_callee);
+    slowPathCall.call();
 }
 
 void JIT::emit_op_create_this(Instruction* currentInstruction)
 {
     int callee = currentInstruction[2].u.operand;
-    WriteBarrierBase<JSCell>* cachedFunction = &currentInstruction[4].u.jsCell;
     RegisterID calleeReg = regT0;
-    RegisterID rareDataReg = regT4;
     RegisterID resultReg = regT0;
     RegisterID allocatorReg = regT1;
     RegisterID structureReg = regT2;
-    RegisterID cachedFunctionReg = regT4;
     RegisterID scratchReg = regT3;
 
     emitLoadPayload(callee, calleeReg);
-    loadPtr(Address(calleeReg, JSFunction::offsetOfRareData()), rareDataReg);
-    addSlowCase(branchTestPtr(Zero, rareDataReg));
-    loadPtr(Address(rareDataReg, FunctionRareData::offsetOfObjectAllocationProfile() + ObjectAllocationProfile::offsetOfAllocator()), allocatorReg);
-    loadPtr(Address(rareDataReg, FunctionRareData::offsetOfObjectAllocationProfile() + ObjectAllocationProfile::offsetOfStructure()), structureReg);
+    loadPtr(Address(calleeReg, JSFunction::offsetOfAllocationProfile() + ObjectAllocationProfile::offsetOfAllocator()), allocatorReg);
+    loadPtr(Address(calleeReg, JSFunction::offsetOfAllocationProfile() + ObjectAllocationProfile::offsetOfStructure()), structureReg);
     addSlowCase(branchTestPtr(Zero, allocatorReg));
 
-    loadPtr(cachedFunction, cachedFunctionReg);
-    Jump hasSeenMultipleCallees = branchPtr(Equal, cachedFunctionReg, TrustedImmPtr(JSCell::seenMultipleCalleeObjects()));
-    addSlowCase(branchPtr(NotEqual, calleeReg, cachedFunctionReg));
-    hasSeenMultipleCallees.link(this);
-
     emitAllocateJSObject(allocatorReg, structureReg, resultReg, scratchReg);
     emitStoreCell(currentInstruction[1].u.operand, resultReg);
 }
 
 void JIT::emitSlow_op_create_this(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    linkSlowCase(iter); // doesn't have rare data
     linkSlowCase(iter); // doesn't have an allocation profile
     linkSlowCase(iter); // allocation failed
-    linkSlowCase(iter); // cached function didn't match
 
     JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_create_this);
     slowPathCall.call();
@@ -1004,8 +1097,8 @@ void JIT::emit_op_to_this(Instruction* currentInstruction)
     emitLoad(thisRegister, regT3, regT2);
 
     addSlowCase(branch32(NotEqual, regT3, TrustedImm32(JSValue::CellTag)));
-    addSlowCase(branch8(NotEqual, Address(regT2, JSCell::typeInfoTypeOffset()), TrustedImm32(FinalObjectType)));
-    loadPtr(Address(regT2, JSCell::structureIDOffset()), regT0);
+    loadPtr(Address(regT2, JSCell::structureOffset()), regT0);
+    addSlowCase(branch8(NotEqual, Address(regT0, Structure::typeInfoTypeOffset()), TrustedImm32(FinalObjectType)));
     loadPtr(cachedStructure, regT2);
     addSlowCase(branchPtr(NotEqual, regT0, regT2));
 }
@@ -1019,19 +1112,6 @@ void JIT::emitSlow_op_to_this(Instruction* currentInstruction, Vector<SlowCaseEn
     slowPathCall.call();
 }
 
-void JIT::emit_op_check_tdz(Instruction* currentInstruction)
-{
-    emitLoadTag(currentInstruction[1].u.operand, regT0);
-    addSlowCase(branch32(Equal, regT0, TrustedImm32(JSValue::EmptyValueTag)));
-}
-
-void JIT::emitSlow_op_check_tdz(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
-{
-    linkSlowCase(iter);
-    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_throw_tdz_error);
-    slowPathCall.call();
-}
-
 void JIT::emit_op_profile_will_call(Instruction* currentInstruction)
 {
     load32(m_vm->enabledProfilerAddress(), regT0);
@@ -1050,282 +1130,63 @@ void JIT::emit_op_profile_did_call(Instruction* currentInstruction)
     profilerDone.link(this);
 }
 
-void JIT::emit_op_has_structure_property(Instruction* currentInstruction)
+void JIT::emit_op_get_arguments_length(Instruction* currentInstruction)
 {
     int dst = currentInstruction[1].u.operand;
-    int base = currentInstruction[2].u.operand;
-    int enumerator = currentInstruction[4].u.operand;
-
-    emitLoadPayload(base, regT0);
-    emitJumpSlowCaseIfNotJSCell(base);
-
-    emitLoadPayload(enumerator, regT1);
-
-    load32(Address(regT0, JSCell::structureIDOffset()), regT0);
-    addSlowCase(branch32(NotEqual, regT0, Address(regT1, JSPropertyNameEnumerator::cachedStructureIDOffset())));
-    
-    move(TrustedImm32(1), regT0);
-    emitStoreBool(dst, regT0);
+    int argumentsRegister = currentInstruction[2].u.operand;
+    addSlowCase(branch32(NotEqual, tagFor(argumentsRegister), TrustedImm32(JSValue::EmptyValueTag)));
+    load32(payloadFor(JSStack::ArgumentCount), regT0);
+    sub32(TrustedImm32(1), regT0);
+    emitStoreInt32(dst, regT0);
 }
 
-void JIT::privateCompileHasIndexedProperty(ByValInfo* byValInfo, ReturnAddressPtr returnAddress, JITArrayMode arrayMode)
-{
-    Instruction* currentInstruction = m_codeBlock->instructions().begin() + byValInfo->bytecodeIndex;
-    
-    PatchableJump badType;
-    
-    // FIXME: Add support for other types like TypedArrays and Arguments.
-    // See https://bugs.webkit.org/show_bug.cgi?id=135033 and https://bugs.webkit.org/show_bug.cgi?id=135034.
-    JumpList slowCases = emitLoadForArrayMode(currentInstruction, arrayMode, badType);
-    move(TrustedImm32(1), regT0);
-    Jump done = jump();
-
-    LinkBuffer patchBuffer(*m_vm, *this, m_codeBlock);
-    
-    patchBuffer.link(badType, CodeLocationLabel(MacroAssemblerCodePtr::createFromExecutableAddress(returnAddress.value())).labelAtOffset(byValInfo->returnAddressToSlowPath));
-    patchBuffer.link(slowCases, CodeLocationLabel(MacroAssemblerCodePtr::createFromExecutableAddress(returnAddress.value())).labelAtOffset(byValInfo->returnAddressToSlowPath));
-    
-    patchBuffer.link(done, byValInfo->badTypeJump.labelAtOffset(byValInfo->badTypeJumpToDone));
-    
-    byValInfo->stubRoutine = FINALIZE_CODE_FOR_STUB(
-        m_codeBlock, patchBuffer,
-        ("Baseline has_indexed_property stub for %s, return point %p", toCString(*m_codeBlock).data(), returnAddress.value()));
-    
-    MacroAssembler::repatchJump(byValInfo->badTypeJump, CodeLocationLabel(byValInfo->stubRoutine->code().code()));
-    MacroAssembler::repatchCall(CodeLocationCall(MacroAssemblerCodePtr(returnAddress)), FunctionPtr(operationHasIndexedPropertyGeneric));
-}
-
-void JIT::emit_op_has_indexed_property(Instruction* currentInstruction)
+void JIT::emitSlow_op_get_arguments_length(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
+    linkSlowCase(iter);
     int dst = currentInstruction[1].u.operand;
     int base = currentInstruction[2].u.operand;
-    int property = currentInstruction[3].u.operand;
-    ArrayProfile* profile = currentInstruction[4].u.arrayProfile;
-    ByValInfo* byValInfo = m_codeBlock->addByValInfo();
-    
-    emitLoadPayload(base, regT0);
-    emitJumpSlowCaseIfNotJSCell(base);
-
-    emitLoadPayload(property, regT1);
-
-    // This is technically incorrect - we're zero-extending an int32. On the hot path this doesn't matter.
-    // We check the value as if it was a uint32 against the m_vectorLength - which will always fail if
-    // number was signed since m_vectorLength is always less than intmax (since the total allocation
-    // size is always less than 4Gb). As such zero extending will have been correct (and extending the value
-    // to 64-bits is necessary since it's used in the address calculation. We zero extend rather than sign
-    // extending since it makes it easier to re-tag the value in the slow case.
-    zeroExtend32ToPtr(regT1, regT1);
-
-    emitArrayProfilingSiteWithCell(regT0, regT2, profile);
-    and32(TrustedImm32(IndexingShapeMask), regT2);
-
-    JITArrayMode mode = chooseArrayMode(profile);
-    PatchableJump badType;
-
-    // FIXME: Add support for other types like TypedArrays and Arguments.
-    // See https://bugs.webkit.org/show_bug.cgi?id=135033 and https://bugs.webkit.org/show_bug.cgi?id=135034.
-    JumpList slowCases = emitLoadForArrayMode(currentInstruction, mode, badType);
-    move(TrustedImm32(1), regT0);
-
-    addSlowCase(badType);
-    addSlowCase(slowCases);
-    
-    Label done = label();
-    
-    emitStoreBool(dst, regT0);
-
-    Label nextHotPath = label();
-    
-    m_byValCompilationInfo.append(ByValCompilationInfo(byValInfo, m_bytecodeOffset, PatchableJump(), badType, mode, profile, done, nextHotPath));
+    callOperation(operationGetArgumentsLength, dst, base);
 }
 
-void JIT::emitSlow_op_has_indexed_property(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+void JIT::emit_op_get_argument_by_val(Instruction* currentInstruction)
 {
     int dst = currentInstruction[1].u.operand;
-    int base = currentInstruction[2].u.operand;
+    int argumentsRegister = currentInstruction[2].u.operand;
     int property = currentInstruction[3].u.operand;
-    ByValInfo* byValInfo = m_byValCompilationInfo[m_byValInstructionIndex].byValInfo;
-    
-    linkSlowCaseIfNotJSCell(iter, base); // base cell check
-    linkSlowCase(iter); // base array check
-    linkSlowCase(iter); // vector length check
-    linkSlowCase(iter); // empty value
-
-    Label slowPath = label();
-    
-    emitLoad(base, regT1, regT0);
-    emitLoad(property, regT3, regT2);
-    Call call = callOperation(operationHasIndexedPropertyDefault, dst, regT1, regT0, regT3, regT2, byValInfo);
-
-    m_byValCompilationInfo[m_byValInstructionIndex].slowPathTarget = slowPath;
-    m_byValCompilationInfo[m_byValInstructionIndex].returnAddress = call;
-    m_byValInstructionIndex++;
-}
-
-void JIT::emit_op_get_direct_pname(Instruction* currentInstruction)
-{
-    int dst = currentInstruction[1].u.operand;
-    int base = currentInstruction[2].u.operand;
-    int index = currentInstruction[4].u.operand;
-    int enumerator = currentInstruction[5].u.operand;
-
-    // Check that base is a cell
-    emitLoadPayload(base, regT0);
-    emitJumpSlowCaseIfNotJSCell(base);
-
-    // Check the structure
-    emitLoadPayload(enumerator, regT1);
-    load32(Address(regT0, JSCell::structureIDOffset()), regT2);
-    addSlowCase(branch32(NotEqual, regT2, Address(regT1, JSPropertyNameEnumerator::cachedStructureIDOffset())));
-
-    // Compute the offset
-    emitLoadPayload(index, regT2);
-    // If index is less than the enumerator's cached inline storage, then it's an inline access
-    Jump outOfLineAccess = branch32(AboveOrEqual, regT2, Address(regT1, JSPropertyNameEnumerator::cachedInlineCapacityOffset()));
-    addPtr(TrustedImm32(JSObject::offsetOfInlineStorage()), regT0);
-    load32(BaseIndex(regT0, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
-    load32(BaseIndex(regT0, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
-    
-    Jump done = jump();
-
-    // Otherwise it's out of line
-    outOfLineAccess.link(this);
-    loadPtr(Address(regT0, JSObject::butterflyOffset()), regT0);
-    addSlowCase(branchIfNotToSpace(regT0));
-    sub32(Address(regT1, JSPropertyNameEnumerator::cachedInlineCapacityOffset()), regT2);
-    neg32(regT2);
-    int32_t offsetOfFirstProperty = static_cast<int32_t>(offsetInButterfly(firstOutOfLineOffset)) * sizeof(EncodedJSValue);
-    load32(BaseIndex(regT0, regT2, TimesEight, offsetOfFirstProperty + OBJECT_OFFSETOF(JSValue, u.asBits.tag)), regT1);
-    load32(BaseIndex(regT0, regT2, TimesEight, offsetOfFirstProperty + OBJECT_OFFSETOF(JSValue, u.asBits.payload)), regT0);
+    addSlowCase(branch32(NotEqual, tagFor(argumentsRegister), TrustedImm32(JSValue::EmptyValueTag)));
+    emitLoad(property, regT1, regT2);
+    addSlowCase(branch32(NotEqual, regT1, TrustedImm32(JSValue::Int32Tag)));
+    add32(TrustedImm32(1), regT2);
+    // regT2 now contains the integer index of the argument we want, including this
+    load32(payloadFor(JSStack::ArgumentCount), regT3);
+    addSlowCase(branch32(AboveOrEqual, regT2, regT3));
     
-    done.link(this);
+    loadPtr(BaseIndex(callFrameRegister, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload) + CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))), regT0);
+    loadPtr(BaseIndex(callFrameRegister, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag) + CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))), regT1);
     emitValueProfilingSite();
     emitStore(dst, regT1, regT0);
 }
 
-void JIT::emitSlow_op_get_direct_pname(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
-{
-    int base = currentInstruction[2].u.operand;
-    linkSlowCaseIfNotJSCell(iter, base);
-    linkSlowCase(iter);
-    linkSlowCase(iter);
-
-    JITSlowPathCall slowPathCall(this, currentInstruction, slow_path_get_direct_pname);
-    slowPathCall.call();
-}
-
-void JIT::emit_op_enumerator_structure_pname(Instruction* currentInstruction)
-{
-    int dst = currentInstruction[1].u.operand;
-    int enumerator = currentInstruction[2].u.operand;
-    int index = currentInstruction[3].u.operand;
-
-    emitLoadPayload(index, regT0);
-    emitLoadPayload(enumerator, regT1);
-    Jump inBounds = branch32(Below, regT0, Address(regT1, JSPropertyNameEnumerator::endStructurePropertyIndexOffset()));
-
-    move(TrustedImm32(JSValue::NullTag), regT2);
-    move(TrustedImm32(0), regT0);
-
-    Jump done = jump();
-    inBounds.link(this);
-
-    loadPtr(Address(regT1, JSPropertyNameEnumerator::cachedPropertyNamesVectorOffset()), regT1);
-    loadPtr(BaseIndex(regT1, regT0, timesPtr()), regT0);
-    move(TrustedImm32(JSValue::CellTag), regT2);
-
-    done.link(this);
-    emitStore(dst, regT2, regT0);
-}
-
-void JIT::emit_op_enumerator_generic_pname(Instruction* currentInstruction)
+void JIT::emitSlow_op_get_argument_by_val(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
     int dst = currentInstruction[1].u.operand;
-    int enumerator = currentInstruction[2].u.operand;
-    int index = currentInstruction[3].u.operand;
-
-    emitLoadPayload(index, regT0);
-    emitLoadPayload(enumerator, regT1);
-    Jump inBounds = branch32(Below, regT0, Address(regT1, JSPropertyNameEnumerator::endGenericPropertyIndexOffset()));
+    int arguments = currentInstruction[2].u.operand;
+    int property = currentInstruction[3].u.operand;
 
-    move(TrustedImm32(JSValue::NullTag), regT2);
-    move(TrustedImm32(0), regT0);
+    linkSlowCase(iter);
+    Jump skipArgumentsCreation = jump();
 
-    Jump done = jump();
-    inBounds.link(this);
+    linkSlowCase(iter);
+    linkSlowCase(iter);
 
-    loadPtr(Address(regT1, JSPropertyNameEnumerator::cachedPropertyNamesVectorOffset()), regT1);
-    loadPtr(BaseIndex(regT1, regT0, timesPtr()), regT0);
-    move(TrustedImm32(JSValue::CellTag), regT2);
+    callOperation(operationCreateArguments);
+    emitStoreCell(arguments, returnValueGPR);
+    emitStoreCell(unmodifiedArgumentsRegister(VirtualRegister(arguments)).offset(), returnValueGPR);
     
-    done.link(this);
-    emitStore(dst, regT2, regT0);
-}
-
-void JIT::emit_op_profile_type(Instruction* currentInstruction)
-{
-    TypeLocation* cachedTypeLocation = currentInstruction[2].u.location;
-    int valueToProfile = currentInstruction[1].u.operand;
-
-    // Load payload in T0. Load tag in T3.
-    emitLoadPayload(valueToProfile, regT0);
-    emitLoadTag(valueToProfile, regT3);
-
-    JumpList jumpToEnd;
-
-    jumpToEnd.append(branch32(Equal, regT3, TrustedImm32(JSValue::EmptyValueTag)));
-
-    // Compile in a predictive type check, if possible, to see if we can skip writing to the log.
-    // These typechecks are inlined to match those of the 32-bit JSValue type checks.
-    if (cachedTypeLocation->m_lastSeenType == TypeUndefined)
-        jumpToEnd.append(branch32(Equal, regT3, TrustedImm32(JSValue::UndefinedTag)));
-    else if (cachedTypeLocation->m_lastSeenType == TypeNull)
-        jumpToEnd.append(branch32(Equal, regT3, TrustedImm32(JSValue::NullTag)));
-    else if (cachedTypeLocation->m_lastSeenType == TypeBoolean)
-        jumpToEnd.append(branch32(Equal, regT3, TrustedImm32(JSValue::BooleanTag)));
-    else if (cachedTypeLocation->m_lastSeenType == TypeMachineInt)
-        jumpToEnd.append(branch32(Equal, regT3, TrustedImm32(JSValue::Int32Tag)));
-    else if (cachedTypeLocation->m_lastSeenType == TypeNumber) {
-        jumpToEnd.append(branch32(Below, regT3, TrustedImm32(JSValue::LowestTag)));
-        jumpToEnd.append(branch32(Equal, regT3, TrustedImm32(JSValue::Int32Tag)));
-    } else if (cachedTypeLocation->m_lastSeenType == TypeString) {
-        Jump isNotCell = branch32(NotEqual, regT3, TrustedImm32(JSValue::CellTag));
-        jumpToEnd.append(branch8(Equal, Address(regT0, JSCell::typeInfoTypeOffset()), TrustedImm32(StringType)));
-        isNotCell.link(this);
-    }
-
-    // Load the type profiling log into T2.
-    TypeProfilerLog* cachedTypeProfilerLog = m_vm->typeProfilerLog();
-    move(TrustedImmPtr(cachedTypeProfilerLog), regT2);
-
-    // Load the next log entry into T1.
-    loadPtr(Address(regT2, TypeProfilerLog::currentLogEntryOffset()), regT1);
-
-    // Store the JSValue onto the log entry.
-    store32(regT0, Address(regT1, TypeProfilerLog::LogEntry::valueOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.payload)));
-    store32(regT3, Address(regT1, TypeProfilerLog::LogEntry::valueOffset() + OBJECT_OFFSETOF(JSValue, u.asBits.tag)));
-
-    // Store the structureID of the cell if argument is a cell, otherwise, store 0 on the log entry.
-    Jump notCell = branch32(NotEqual, regT3, TrustedImm32(JSValue::CellTag));
-    load32(Address(regT0, JSCell::structureIDOffset()), regT0);
-    store32(regT0, Address(regT1, TypeProfilerLog::LogEntry::structureIDOffset()));
-    Jump skipNotCell = jump();
-    notCell.link(this);
-    store32(TrustedImm32(0), Address(regT1, TypeProfilerLog::LogEntry::structureIDOffset()));
-    skipNotCell.link(this);
-
-    // Store the typeLocation on the log entry.
-    move(TrustedImmPtr(cachedTypeLocation), regT0);
-    store32(regT0, Address(regT1, TypeProfilerLog::LogEntry::locationOffset()));
-
-    // Increment the current log entry.
-    addPtr(TrustedImm32(sizeof(TypeProfilerLog::LogEntry)), regT1);
-    store32(regT1, Address(regT2, TypeProfilerLog::currentLogEntryOffset()));
-    jumpToEnd.append(branchPtr(NotEqual, regT1, TrustedImmPtr(cachedTypeProfilerLog->logEndPtr())));
-    // Clear the log if we're at the end of the log.
-    callOperation(operationProcessTypeProfilerLog);
-
-    jumpToEnd.link(this);
+    skipArgumentsCreation.link(this);
+    emitLoad(arguments, regT1, regT0);
+    emitLoad(property, regT3, regT2);
+    callOperation(WithProfile, operationGetByValGeneric, dst, regT1, regT0, regT3, regT2);
 }
 
 } // namespace JSC