webkitgtk-2.4.9webkitgtk-2.4.9

1 files changed, 255 insertions, 283 deletions

diff --git a/Source/JavaScriptCore/llint/LLIntSlowPaths.cpp b/Source/JavaScriptCore/llint/LLIntSlowPaths.cpp
index 56db62f38..26264171d 100644
--- a/Source/JavaScriptCore/llint/LLIntSlowPaths.cpp
+++ b/Source/JavaScriptCore/llint/LLIntSlowPaths.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2011-2015 Apple Inc. All rights reserved.
+ * Copyright (C) 2011, 2012, 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -26,34 +26,32 @@
 #include "config.h"
 #include "LLIntSlowPaths.h"
 
+#if ENABLE(LLINT)
+
+#include "Arguments.h"
 #include "ArrayConstructor.h"
 #include "CallFrame.h"
 #include "CommonSlowPaths.h"
 #include "CommonSlowPathsExceptions.h"
-#include "Error.h"
-#include "ErrorHandlingScope.h"
-#include "Exception.h"
-#include "ExceptionFuzz.h"
 #include "GetterSetter.h"
 #include "HostCallReturnValue.h"
 #include "Interpreter.h"
 #include "JIT.h"
 #include "JITExceptions.h"
-#include "JSLexicalEnvironment.h"
-#include "JSCInlines.h"
+#include "JSActivation.h"
 #include "JSCJSValue.h"
 #include "JSGlobalObjectFunctions.h"
+#include "JSNameScope.h"
+#include "JSPropertyNameIterator.h"
 #include "JSStackInlines.h"
 #include "JSString.h"
 #include "JSWithScope.h"
 #include "LLIntCommon.h"
 #include "LLIntExceptions.h"
-#include "LegacyProfiler.h"
 #include "LowLevelInterpreter.h"
 #include "ObjectConstructor.h"
-#include "ProtoCallFrame.h"
+#include "Operations.h"
 #include "StructureRareDataInlines.h"
-#include "VMInlines.h"
 #include <wtf/StringPrintStream.h>
 
 namespace JSC { namespace LLInt {
@@ -84,7 +82,7 @@ namespace JSC { namespace LLInt {
         return encodeResult(first, second);        \
     } while (false)
 
-#define LLINT_END_IMPL() LLINT_RETURN_TWO(pc, 0)
+#define LLINT_END_IMPL() LLINT_RETURN_TWO(pc, exec)
 
 #define LLINT_THROW(exceptionToThrow) do {                        \
         vm.throwException(exec, exceptionToThrow);                \
@@ -93,7 +91,6 @@ namespace JSC { namespace LLInt {
     } while (false)
 
 #define LLINT_CHECK_EXCEPTION() do {                    \
-        doExceptionFuzzingIfEnabled(exec, "LLIntSlowPaths", pc);    \
         if (UNLIKELY(vm.exception())) {                 \
             pc = returnToThrow(exec);                   \
             LLINT_END_IMPL();                           \
@@ -122,14 +119,6 @@ namespace JSC { namespace LLInt {
         LLINT_END_IMPL();                       \
     } while (false)
 
-#define LLINT_RETURN_WITH_PC_ADJUSTMENT(value, pcAdjustment) do { \
-        JSValue __r_returnValue = (value);      \
-        LLINT_CHECK_EXCEPTION();                \
-        LLINT_OP(1) = __r_returnValue;          \
-        pc += (pcAdjustment);                   \
-        LLINT_END_IMPL();                       \
-    } while (false)
-
 #define LLINT_RETURN_PROFILED(opcode, value) do {               \
         JSValue __rp_returnValue = (value);                     \
         LLINT_CHECK_EXCEPTION();                                \
@@ -148,28 +137,20 @@ namespace JSC { namespace LLInt {
 #define LLINT_CALL_THROW(exec, exceptionToThrow) do {                   \
         ExecState* __ct_exec = (exec);                                  \
         vm.throwException(__ct_exec, exceptionToThrow);                 \
-        LLINT_CALL_END_IMPL(0, callToThrow(__ct_exec));                 \
+        LLINT_CALL_END_IMPL(__ct_exec, callToThrow(__ct_exec));         \
     } while (false)
 
-#define LLINT_CALL_CHECK_EXCEPTION(exec, execCallee) do {               \
+#define LLINT_CALL_CHECK_EXCEPTION(exec) do {                           \
         ExecState* __cce_exec = (exec);                                 \
-        ExecState* __cce_execCallee = (execCallee);                     \
-        doExceptionFuzzingIfEnabled(__cce_exec, "LLIntSlowPaths/call", nullptr); \
         if (UNLIKELY(vm.exception()))                                   \
-            LLINT_CALL_END_IMPL(0, callToThrow(__cce_execCallee));      \
+            LLINT_CALL_END_IMPL(__cce_exec, callToThrow(__cce_exec));   \
     } while (false)
 
-#define LLINT_CALL_RETURN(exec, execCallee, callTarget) do {            \
+#define LLINT_CALL_RETURN(exec, callTarget) do {                        \
         ExecState* __cr_exec = (exec);                                  \
-        ExecState* __cr_execCallee = (execCallee);                      \
         void* __cr_callTarget = (callTarget);                           \
-        LLINT_CALL_CHECK_EXCEPTION(__cr_exec, __cr_execCallee);         \
-        LLINT_CALL_END_IMPL(__cr_execCallee, __cr_callTarget);          \
-    } while (false)
-
-#define LLINT_RETURN_CALLEE_FRAME(execCallee) do {                      \
-        ExecState* __rcf_exec = (execCallee);                           \
-        LLINT_RETURN_TWO(pc, __rcf_exec);                               \
+        LLINT_CALL_CHECK_EXCEPTION(__cr_exec->callerFrame());           \
+        LLINT_CALL_END_IMPL(__cr_exec, __cr_callTarget);                \
     } while (false)
 
 extern "C" SlowPathReturnType llint_trace_operand(ExecState* exec, Instruction* pc, int fromWhere, int operand)
@@ -255,15 +236,12 @@ LLINT_SLOW_PATH_DECL(trace_arityCheck_for_construct)
 
 LLINT_SLOW_PATH_DECL(trace)
 {
-    dataLogF("%p / %p: executing bc#%zu, %s, pc = %p\n",
+    dataLogF("%p / %p: executing bc#%zu, %s, scope %p, pc = %p\n",
             exec->codeBlock(),
             exec,
             static_cast<intptr_t>(pc - exec->codeBlock()->instructions().begin()),
-            opcodeNames[exec->vm().interpreter->getOpcodeID(pc[0].u.opcode)], pc);
-    if (exec->vm().interpreter->getOpcodeID(pc[0].u.opcode) == op_enter) {
-        dataLogF("Frame will eventually return to %p\n", exec->returnPC().value());
-        *bitwise_cast<volatile char*>(exec->returnPC().value());
-    }
+            opcodeNames[exec->vm().interpreter->getOpcodeID(pc[0].u.opcode)],
+            exec->scope(), pc);
     if (exec->vm().interpreter->getOpcodeID(pc[0].u.opcode) == op_ret) {
         dataLogF("Will be returning to %p\n", exec->returnPC().value());
         dataLogF("The new cfr will be %p\n", exec->callerFrame());
@@ -332,7 +310,6 @@ inline bool jitCompileAndSetHeuristics(CodeBlock* codeBlock, ExecState* exec)
         }
     }
     default:
-        dataLog("Unexpected code block in LLInt: ", *codeBlock, "\n");
         RELEASE_ASSERT_NOT_REACHED();
         return false;
     }
@@ -348,17 +325,15 @@ static SlowPathReturnType entryOSR(ExecState* exec, Instruction*, CodeBlock* cod
     
     if (!shouldJIT(exec)) {
         codeBlock->dontJITAnytimeSoon();
-        LLINT_RETURN_TWO(0, 0);
+        LLINT_RETURN_TWO(0, exec);
     }
     if (!jitCompileAndSetHeuristics(codeBlock, exec))
-        LLINT_RETURN_TWO(0, 0);
+        LLINT_RETURN_TWO(0, exec);
     
     if (kind == Prologue)
-        LLINT_RETURN_TWO(codeBlock->jitCode()->executableAddress(), 0);
+        LLINT_RETURN_TWO(codeBlock->jitCode()->executableAddress(), exec);
     ASSERT(kind == ArityCheck);
-    LLINT_RETURN_TWO(codeBlock->jitCode()->addressForCall(
-        *codeBlock->vm(), codeBlock->ownerExecutable(), MustCheckArity,
-        RegisterPreservationNotRequired).executableAddress(), 0);
+    LLINT_RETURN_TWO(codeBlock->jitCodeWithArityCheck().executableAddress(), exec);
 }
 #else // ENABLE(JIT)
 static SlowPathReturnType entryOSR(ExecState* exec, Instruction*, CodeBlock* codeBlock, const char*, EntryKind)
@@ -406,11 +381,11 @@ LLINT_SLOW_PATH_DECL(loop_osr)
     
     if (!shouldJIT(exec)) {
         codeBlock->dontJITAnytimeSoon();
-        LLINT_RETURN_TWO(0, 0);
+        LLINT_RETURN_TWO(0, exec);
     }
     
     if (!jitCompileAndSetHeuristics(codeBlock, exec))
-        LLINT_RETURN_TWO(0, 0);
+        LLINT_RETURN_TWO(0, exec);
     
     ASSERT(codeBlock->jitType() == JITCode::BaselineJIT);
     
@@ -423,11 +398,10 @@ LLINT_SLOW_PATH_DECL(loop_osr)
     void* jumpTarget = codeBlock->jitCode()->executableAddressAtOffset(mapping->m_machineCodeOffset);
     ASSERT(jumpTarget);
     
-    LLINT_RETURN_TWO(jumpTarget, exec->topOfFrame());
+    LLINT_RETURN_TWO(jumpTarget, exec);
 #else // ENABLE(JIT)
-    UNUSED_PARAM(pc);
     codeBlock->dontJITAnytimeSoon();
-    LLINT_RETURN_TWO(0, 0);
+    LLINT_RETURN_TWO(0, exec);
 #endif // ENABLE(JIT)
 }
 
@@ -461,32 +435,26 @@ LLINT_SLOW_PATH_DECL(stack_check)
     dataLogF("CodeBlock = %p.\n", exec->codeBlock());
     dataLogF("Num callee registers = %u.\n", exec->codeBlock()->m_numCalleeRegisters);
     dataLogF("Num vars = %u.\n", exec->codeBlock()->m_numVars);
-
-#if ENABLE(JIT)
-    dataLogF("Current end is at %p.\n", exec->vm().stackLimit());
-#else
-    dataLogF("Current end is at %p.\n", exec->vm().jsStackLimit());
+    dataLogF("Current end is at %p.\n", exec->vm().interpreter->stack().end());
 #endif
+    ASSERT(!exec->vm().interpreter->stack().containsAddress(&exec->registers()[virtualRegisterForLocal(exec->codeBlock()->m_numCalleeRegisters).offset()]));
+    if (UNLIKELY(!vm.interpreter->stack().grow(&exec->registers()[virtualRegisterForLocal(exec->codeBlock()->m_numCalleeRegisters).offset()]))) {
+        exec = exec->callerFrame();
+        CommonSlowPaths::interpreterThrowInCaller(exec, createStackOverflowError(exec));
+        pc = returnToThrowForThrownException(exec);
+    }
+    LLINT_END_IMPL();
+}
 
+LLINT_SLOW_PATH_DECL(slow_path_create_activation)
+{
+    LLINT_BEGIN();
+#if LLINT_SLOW_PATH_TRACING
+    dataLogF("Creating an activation, exec = %p!\n", exec);
 #endif
-    // If the stack check succeeds and we don't need to throw the error, then
-    // we'll return 0 instead. The prologue will check for a non-zero value
-    // when determining whether to set the callFrame or not.
-
-    // For JIT enabled builds which uses the C stack, the stack is not growable.
-    // Hence, if we get here, then we know a stack overflow is imminent. So, just
-    // throw the StackOverflowError unconditionally.
-#if !ENABLE(JIT)
-    ASSERT(!vm.interpreter->stack().containsAddress(exec->topOfFrame()));
-    if (LIKELY(vm.interpreter->stack().ensureCapacityFor(exec->topOfFrame())))
-        LLINT_RETURN_TWO(pc, 0);
-#endif
-
-    vm.topCallFrame = exec;
-    ErrorHandlingScope errorScope(vm);
-    CommonSlowPaths::interpreterThrowInCaller(exec, createStackOverflowError(exec));
-    pc = returnToThrowForThrownException(exec);
-    LLINT_RETURN_TWO(pc, exec);
+    JSActivation* activation = JSActivation::create(vm, exec, exec->codeBlock());
+    exec->setScope(activation);
+    LLINT_RETURN(JSValue(activation));
 }
 
 LLINT_SLOW_PATH_DECL(slow_path_new_object)
@@ -532,11 +500,11 @@ LLINT_SLOW_PATH_DECL(slow_path_check_has_instance)
         JSObject* baseObject = asObject(baseVal);
         ASSERT(!baseObject->structure()->typeInfo().implementsDefaultHasInstance());
         if (baseObject->structure()->typeInfo().implementsHasInstance()) {
-            JSValue result = jsBoolean(baseObject->methodTable()->customHasInstance(baseObject, exec, value));
-            LLINT_RETURN_WITH_PC_ADJUSTMENT(result, pc[4].u.operand);
+            pc += pc[4].u.operand;
+            LLINT_RETURN(jsBoolean(baseObject->methodTable()->customHasInstance(baseObject, exec, value)));
         }
     }
-    LLINT_THROW(createInvalidInstanceofParameterError(exec, baseVal));
+    LLINT_THROW(createInvalidParameterError(exec, "instanceof", baseVal));
 }
 
 LLINT_SLOW_PATH_DECL(slow_path_instanceof)
@@ -570,17 +538,16 @@ LLINT_SLOW_PATH_DECL(slow_path_get_by_id)
         Structure* structure = baseCell->structure();
         
         if (!structure->isUncacheableDictionary()
-            && !structure->typeInfo().prohibitsPropertyCaching()
-            && !structure->typeInfo().newImpurePropertyFiresWatchpoints()) {
+            && !structure->typeInfo().prohibitsPropertyCaching()) {
             ConcurrentJITLocker locker(codeBlock->m_lock);
-
+            
             pc[4].u.structure.set(
                 vm, codeBlock->ownerExecutable(), structure);
             if (isInlineOffset(slot.cachedOffset())) {
-                pc[0].u.opcode = LLInt::getOpcode(op_get_by_id);
+                pc[0].u.opcode = LLInt::getOpcode(llint_op_get_by_id);
                 pc[5].u.operand = offsetInInlineStorage(slot.cachedOffset()) * sizeof(JSValue) + JSObject::offsetOfInlineStorage();
             } else {
-                pc[0].u.opcode = LLInt::getOpcode(op_get_by_id_out_of_line);
+                pc[0].u.opcode = LLInt::getOpcode(llint_op_get_by_id_out_of_line);
                 pc[5].u.operand = offsetInButterfly(slot.cachedOffset()) * sizeof(JSValue);
             }
         }
@@ -589,7 +556,7 @@ LLINT_SLOW_PATH_DECL(slow_path_get_by_id)
     if (!LLINT_ALWAYS_ACCESS_SLOW
         && isJSArray(baseValue)
         && ident == exec->propertyNames().length) {
-        pc[0].u.opcode = LLInt::getOpcode(op_get_array_length);
+        pc[0].u.opcode = LLInt::getOpcode(llint_op_get_array_length);
         ArrayProfile* arrayProfile = codeBlock->getOrAddArrayProfile(pc - codeBlock->instructions().begin());
         arrayProfile->observeStructure(baseValue.asCell()->structure());
         pc[4].u.arrayProfile = arrayProfile;
@@ -625,7 +592,7 @@ LLINT_SLOW_PATH_DECL(slow_path_put_by_id)
     
     if (!LLINT_ALWAYS_ACCESS_SLOW
         && baseValue.isCell()
-        && slot.isCacheablePut()) {
+        && slot.isCacheable()) {
         
         JSCell* baseCell = baseValue.asCell();
         Structure* structure = baseCell->structure();
@@ -642,9 +609,9 @@ LLINT_SLOW_PATH_DECL(slow_path_put_by_id)
                     
                     // This is needed because some of the methods we call
                     // below may GC.
-                    pc[0].u.opcode = LLInt::getOpcode(op_put_by_id);
+                    pc[0].u.opcode = LLInt::getOpcode(llint_op_put_by_id);
 
-                    if (normalizePrototypeChain(exec, structure) != InvalidPrototypeChain) {
+                    if (normalizePrototypeChain(exec, baseCell) != InvalidPrototypeChain) {
                         ASSERT(structure->previousID()->isObject());
                         pc[4].u.structure.set(
                             vm, codeBlock->ownerExecutable(), structure->previousID());
@@ -661,26 +628,25 @@ LLINT_SLOW_PATH_DECL(slow_path_put_by_id)
                     
                         if (pc[8].u.operand) {
                             if (isInlineOffset(slot.cachedOffset()))
-                                pc[0].u.opcode = LLInt::getOpcode(op_put_by_id_transition_direct);
+                                pc[0].u.opcode = LLInt::getOpcode(llint_op_put_by_id_transition_direct);
                             else
-                                pc[0].u.opcode = LLInt::getOpcode(op_put_by_id_transition_direct_out_of_line);
+                                pc[0].u.opcode = LLInt::getOpcode(llint_op_put_by_id_transition_direct_out_of_line);
                         } else {
                             if (isInlineOffset(slot.cachedOffset()))
-                                pc[0].u.opcode = LLInt::getOpcode(op_put_by_id_transition_normal);
+                                pc[0].u.opcode = LLInt::getOpcode(llint_op_put_by_id_transition_normal);
                             else
-                                pc[0].u.opcode = LLInt::getOpcode(op_put_by_id_transition_normal_out_of_line);
+                                pc[0].u.opcode = LLInt::getOpcode(llint_op_put_by_id_transition_normal_out_of_line);
                         }
                     }
                 }
             } else {
-                structure->didCachePropertyReplacement(vm, slot.cachedOffset());
                 pc[4].u.structure.set(
                     vm, codeBlock->ownerExecutable(), structure);
                 if (isInlineOffset(slot.cachedOffset())) {
-                    pc[0].u.opcode = LLInt::getOpcode(op_put_by_id);
+                    pc[0].u.opcode = LLInt::getOpcode(llint_op_put_by_id);
                     pc[5].u.operand = offsetInInlineStorage(slot.cachedOffset()) * sizeof(JSValue) + JSObject::offsetOfInlineStorage();
                 } else {
-                    pc[0].u.opcode = LLInt::getOpcode(op_put_by_id_out_of_line);
+                    pc[0].u.opcode = LLInt::getOpcode(llint_op_put_by_id_out_of_line);
                     pc[5].u.operand = offsetInButterfly(slot.cachedOffset()) * sizeof(JSValue);
                 }
             }
@@ -705,14 +671,8 @@ LLINT_SLOW_PATH_DECL(slow_path_del_by_id)
 inline JSValue getByVal(ExecState* exec, JSValue baseValue, JSValue subscript)
 {
     if (LIKELY(baseValue.isCell() && subscript.isString())) {
-        VM& vm = exec->vm();
-        Structure& structure = *baseValue.asCell()->structure(vm);
-        if (JSCell::canUseFastGetOwnProperty(structure)) {
-            if (RefPtr<AtomicStringImpl> existingAtomicString = asString(subscript)->toExistingAtomicString(exec)) {
-                if (JSValue result = baseValue.asCell()->fastGetOwnProperty(vm, structure, existingAtomicString.get()))
-                    return result;
-            }
-        }
+        if (JSValue result = baseValue.asCell()->fastGetOwnProperty(exec, asString(subscript)->value(exec)))
+            return result;
     }
     
     if (subscript.isUInt32()) {
@@ -723,12 +683,10 @@ inline JSValue getByVal(ExecState* exec, JSValue baseValue, JSValue subscript)
         return baseValue.get(exec, i);
     }
 
-    baseValue.requireObjectCoercible(exec);
-    if (exec->hadException())
-        return jsUndefined();
-    auto property = subscript.toPropertyKey(exec);
-    if (exec->hadException())
-        return jsUndefined();
+    if (isName(subscript))
+        return baseValue.get(exec, jsCast<NameInstance*>(subscript.asCell())->privateName());
+    
+    Identifier property(exec, subscript.toString(exec)->value(exec));
     return baseValue.get(exec, property);
 }
 
@@ -738,6 +696,26 @@ LLINT_SLOW_PATH_DECL(slow_path_get_by_val)
     LLINT_RETURN_PROFILED(op_get_by_val, getByVal(exec, LLINT_OP_C(2).jsValue(), LLINT_OP_C(3).jsValue()));
 }
 
+LLINT_SLOW_PATH_DECL(slow_path_get_argument_by_val)
+{
+    LLINT_BEGIN();
+    JSValue arguments = LLINT_OP(2).jsValue();
+    if (!arguments) {
+        arguments = Arguments::create(vm, exec);
+        LLINT_CHECK_EXCEPTION();
+        LLINT_OP(2) = arguments;
+        exec->uncheckedR(unmodifiedArgumentsRegister(VirtualRegister(pc[2].u.operand)).offset()) = arguments;
+    }
+    
+    LLINT_RETURN_PROFILED(op_get_argument_by_val, getByVal(exec, arguments, LLINT_OP_C(3).jsValue()));
+}
+
+LLINT_SLOW_PATH_DECL(slow_path_get_by_pname)
+{
+    LLINT_BEGIN();
+    LLINT_RETURN(getByVal(exec, LLINT_OP_C(2).jsValue(), LLINT_OP_C(3).jsValue()));
+}
+
 LLINT_SLOW_PATH_DECL(slow_path_put_by_val)
 {
     LLINT_BEGIN();
@@ -760,7 +738,13 @@ LLINT_SLOW_PATH_DECL(slow_path_put_by_val)
         LLINT_END();
     }
 
-    auto property = subscript.toPropertyKey(exec);
+    if (isName(subscript)) {
+        PutPropertySlot slot(baseValue, exec->codeBlock()->isStrictMode());
+        baseValue.put(exec, jsCast<NameInstance*>(subscript.asCell())->privateName(), value, slot);
+        LLINT_END();
+    }
+
+    Identifier property(exec, subscript.toString(exec)->value(exec));
     LLINT_CHECK_EXCEPTION();
     PutPropertySlot slot(baseValue, exec->codeBlock()->isStrictMode());
     baseValue.put(exec, property, value, slot);
@@ -776,34 +760,19 @@ LLINT_SLOW_PATH_DECL(slow_path_put_by_val_direct)
     JSValue value = LLINT_OP_C(3).jsValue();
     RELEASE_ASSERT(baseValue.isObject());
     JSObject* baseObject = asObject(baseValue);
-    bool isStrictMode = exec->codeBlock()->isStrictMode();
     if (LIKELY(subscript.isUInt32())) {
-        // Despite its name, JSValue::isUInt32 will return true only for positive boxed int32_t; all those values are valid array indices.
-        ASSERT(isIndex(subscript.asUInt32()));
-        baseObject->putDirectIndex(exec, subscript.asUInt32(), value, 0, isStrictMode ? PutDirectIndexShouldThrow : PutDirectIndexShouldNotThrow);
-        LLINT_END();
-    }
-
-    if (subscript.isDouble()) {
-        double subscriptAsDouble = subscript.asDouble();
-        uint32_t subscriptAsUInt32 = static_cast<uint32_t>(subscriptAsDouble);
-        if (subscriptAsDouble == subscriptAsUInt32 && isIndex(subscriptAsUInt32)) {
-            baseObject->putDirectIndex(exec, subscriptAsUInt32, value, 0, isStrictMode ? PutDirectIndexShouldThrow : PutDirectIndexShouldNotThrow);
-            LLINT_END();
+        uint32_t i = subscript.asUInt32();
+        baseObject->putDirectIndex(exec, i, value);
+    } else if (isName(subscript)) {
+        PutPropertySlot slot(baseObject, exec->codeBlock()->isStrictMode());
+        baseObject->putDirect(exec->vm(), jsCast<NameInstance*>(subscript.asCell())->privateName(), value, slot);
+    } else {
+        Identifier property(exec, subscript.toString(exec)->value(exec));
+        if (!exec->vm().exception()) { // Don't put to an object if toString threw an exception.
+            PutPropertySlot slot(baseObject, exec->codeBlock()->isStrictMode());
+            baseObject->putDirect(exec->vm(), property, value, slot);
         }
     }
-
-    // Don't put to an object if toString threw an exception.
-    auto property = subscript.toPropertyKey(exec);
-    if (exec->vm().exception())
-        LLINT_END();
-
-    if (Optional<uint32_t> index = parseIndex(property))
-        baseObject->putDirectIndex(exec, index.value(), value, 0, isStrictMode ? PutDirectIndexShouldThrow : PutDirectIndexShouldNotThrow);
-    else {
-        PutPropertySlot slot(baseObject, isStrictMode);
-        baseObject->putDirect(exec->vm(), property, value, slot);
-    }
     LLINT_END();
 }
 
@@ -820,9 +789,11 @@ LLINT_SLOW_PATH_DECL(slow_path_del_by_val)
     uint32_t i;
     if (subscript.getUInt32(i))
         couldDelete = baseObject->methodTable()->deletePropertyByIndex(baseObject, exec, i);
+    else if (isName(subscript))
+        couldDelete = baseObject->methodTable()->deleteProperty(baseObject, exec, jsCast<NameInstance*>(subscript.asCell())->privateName());
     else {
         LLINT_CHECK_EXCEPTION();
-        auto property = subscript.toPropertyKey(exec);
+        Identifier property(exec, subscript.toString(exec)->value(exec));
         LLINT_CHECK_EXCEPTION();
         couldDelete = baseObject->methodTable()->deleteProperty(baseObject, exec, property);
     }
@@ -842,39 +813,13 @@ LLINT_SLOW_PATH_DECL(slow_path_put_by_index)
     LLINT_END();
 }
 
-LLINT_SLOW_PATH_DECL(slow_path_put_getter_by_id)
-{
-    LLINT_BEGIN();
-    ASSERT(LLINT_OP(1).jsValue().isObject());
-    JSObject* baseObj = asObject(LLINT_OP(1).jsValue());
-    
-    JSValue getter = LLINT_OP(3).jsValue();
-    ASSERT(getter.isObject());
-    
-    baseObj->putGetter(exec, exec->codeBlock()->identifier(pc[2].u.operand), asObject(getter));
-    LLINT_END();
-}
-
-LLINT_SLOW_PATH_DECL(slow_path_put_setter_by_id)
-{
-    LLINT_BEGIN();
-    ASSERT(LLINT_OP(1).jsValue().isObject());
-    JSObject* baseObj = asObject(LLINT_OP(1).jsValue());
-    
-    JSValue setter = LLINT_OP(3).jsValue();
-    ASSERT(setter.isObject());
-    
-    baseObj->putSetter(exec, exec->codeBlock()->identifier(pc[2].u.operand), asObject(setter));
-    LLINT_END();
-}
-
 LLINT_SLOW_PATH_DECL(slow_path_put_getter_setter)
 {
     LLINT_BEGIN();
     ASSERT(LLINT_OP(1).jsValue().isObject());
     JSObject* baseObj = asObject(LLINT_OP(1).jsValue());
     
-    GetterSetter* accessor = GetterSetter::create(vm, exec->lexicalGlobalObject());
+    GetterSetter* accessor = GetterSetter::create(vm);
     LLINT_CHECK_EXCEPTION();
     
     JSValue getter = LLINT_OP(3).jsValue();
@@ -884,9 +829,9 @@ LLINT_SLOW_PATH_DECL(slow_path_put_getter_setter)
     ASSERT(getter.isObject() || setter.isObject());
     
     if (!getter.isUndefined())
-        accessor->setGetter(vm, exec->lexicalGlobalObject(), asObject(getter));
+        accessor->setGetter(vm, asObject(getter));
     if (!setter.isUndefined())
-        accessor->setSetter(vm, exec->lexicalGlobalObject(), asObject(setter));
+        accessor->setSetter(vm, asObject(setter));
     baseObj->putDirectAccessor(
         exec,
         exec->codeBlock()->identifier(pc[2].u.operand),
@@ -1002,21 +947,21 @@ LLINT_SLOW_PATH_DECL(slow_path_new_func)
 {
     LLINT_BEGIN();
     CodeBlock* codeBlock = exec->codeBlock();
-    ASSERT(codeBlock->codeType() != FunctionCode || !codeBlock->needsActivation() || exec->hasActivation());
-    JSScope* scope = exec->uncheckedR(pc[2].u.operand).Register::scope();
+    ASSERT(codeBlock->codeType() != FunctionCode
+           || !codeBlock->needsFullScopeChain()
+           || exec->uncheckedR(codeBlock->activationRegister().offset()).jsValue());
 #if LLINT_SLOW_PATH_TRACING
     dataLogF("Creating function!\n");
 #endif
-    LLINT_RETURN(JSFunction::create(vm, codeBlock->functionDecl(pc[3].u.operand), scope));
+    LLINT_RETURN(JSFunction::create(vm, codeBlock->functionDecl(pc[2].u.operand), exec->scope()));
 }
 
 LLINT_SLOW_PATH_DECL(slow_path_new_func_exp)
 {
     LLINT_BEGIN();
     CodeBlock* codeBlock = exec->codeBlock();
-    JSScope* scope = exec->uncheckedR(pc[2].u.operand).Register::scope();
-    FunctionExecutable* function = codeBlock->functionExpr(pc[3].u.operand);
-    JSFunction* func = JSFunction::create(vm, function, scope);
+    FunctionExecutable* function = codeBlock->functionExpr(pc[2].u.operand);
+    JSFunction* func = JSFunction::create(vm, function, exec->scope());
     
     LLINT_RETURN(func);
 }
@@ -1032,6 +977,7 @@ static SlowPathReturnType handleHostCall(ExecState* execCallee, Instruction* pc,
     ExecState* exec = execCallee->callerFrame();
     VM& vm = exec->vm();
 
+    execCallee->setScope(exec->scope());
     execCallee->setCodeBlock(0);
     execCallee->clearReturnPC();
 
@@ -1046,7 +992,7 @@ static SlowPathReturnType handleHostCall(ExecState* execCallee, Instruction* pc,
             execCallee->setCallee(asObject(callee));
             vm.hostCallReturnValue = JSValue::decode(callData.native.function(execCallee));
             
-            LLINT_CALL_RETURN(execCallee, execCallee, LLInt::getCodePtr(getHostCallReturnValue));
+            LLINT_CALL_RETURN(execCallee, LLInt::getCodePtr(getHostCallReturnValue));
         }
         
 #if LLINT_SLOW_PATH_TRACING
@@ -1069,7 +1015,7 @@ static SlowPathReturnType handleHostCall(ExecState* execCallee, Instruction* pc,
         execCallee->setCallee(asObject(callee));
         vm.hostCallReturnValue = JSValue::decode(constructData.native.function(execCallee));
 
-        LLINT_CALL_RETURN(execCallee, execCallee, LLInt::getCodePtr(getHostCallReturnValue));
+        LLINT_CALL_RETURN(execCallee, LLInt::getCodePtr(getHostCallReturnValue));
     }
     
 #if LLINT_SLOW_PATH_TRACING
@@ -1082,12 +1028,10 @@ static SlowPathReturnType handleHostCall(ExecState* execCallee, Instruction* pc,
 
 inline SlowPathReturnType setUpCall(ExecState* execCallee, Instruction* pc, CodeSpecializationKind kind, JSValue calleeAsValue, LLIntCallLinkInfo* callLinkInfo = 0)
 {
-    ExecState* exec = execCallee->callerFrame();
-
 #if LLINT_SLOW_PATH_TRACING
-    dataLogF("Performing call with recorded PC = %p\n", exec->currentVPC());
+    dataLogF("Performing call with recorded PC = %p\n", execCallee->callerFrame()->currentVPC());
 #endif
-    
+
     JSCell* calleeAsFunctionCell = getJSFunction(calleeAsValue);
     if (!calleeAsFunctionCell)
         return handleHostCall(execCallee, pc, calleeAsValue, kind);
@@ -1095,35 +1039,30 @@ inline SlowPathReturnType setUpCall(ExecState* execCallee, Instruction* pc, Code
     JSFunction* callee = jsCast<JSFunction*>(calleeAsFunctionCell);
     JSScope* scope = callee->scopeUnchecked();
     VM& vm = *scope->vm();
+    execCallee->setScope(scope);
     ExecutableBase* executable = callee->executable();
     
     MacroAssemblerCodePtr codePtr;
     CodeBlock* codeBlock = 0;
     if (executable->isHostFunction())
-        codePtr = executable->entrypointFor(vm, kind, MustCheckArity, RegisterPreservationNotRequired);
+        codePtr = executable->hostCodeEntryFor(kind);
     else {
         FunctionExecutable* functionExecutable = static_cast<FunctionExecutable*>(executable);
-
-        if (!isCall(kind) && functionExecutable->constructAbility() == ConstructAbility::CannotConstruct)
-            LLINT_CALL_THROW(exec, createNotAConstructorError(exec, callee));
-
-        JSObject* error = functionExecutable->prepareForExecution(execCallee, callee, scope, kind);
+        JSObject* error = functionExecutable->prepareForExecution(execCallee, callee->scope(), kind);
         if (error)
-            LLINT_CALL_THROW(exec, error);
+            LLINT_CALL_THROW(execCallee->callerFrame(), error);
         codeBlock = functionExecutable->codeBlockFor(kind);
         ASSERT(codeBlock);
-        ArityCheckMode arity;
         if (execCallee->argumentCountIncludingThis() < static_cast<size_t>(codeBlock->numParameters()))
-            arity = MustCheckArity;
+            codePtr = functionExecutable->jsCodeWithArityCheckEntryFor(kind);
         else
-            arity = ArityCheckNotRequired;
-        codePtr = functionExecutable->entrypointFor(vm, kind, arity, RegisterPreservationNotRequired);
+            codePtr = functionExecutable->jsCodeEntryFor(kind);
     }
     
-    ASSERT(!!codePtr);
-    
     if (!LLINT_ALWAYS_ACCESS_SLOW && callLinkInfo) {
-        CodeBlock* callerCodeBlock = exec->codeBlock();
+        ExecState* execCaller = execCallee->callerFrame();
+        
+        CodeBlock* callerCodeBlock = execCaller->codeBlock();
 
         ConcurrentJITLocker locker(callerCodeBlock->m_lock);
         
@@ -1133,10 +1072,10 @@ inline SlowPathReturnType setUpCall(ExecState* execCallee, Instruction* pc, Code
         callLinkInfo->lastSeenCallee.set(vm, callerCodeBlock->ownerExecutable(), callee);
         callLinkInfo->machineCodeTarget = codePtr;
         if (codeBlock)
-            codeBlock->linkIncomingCall(exec, callLinkInfo);
+            codeBlock->linkIncomingCall(execCaller, callLinkInfo);
     }
 
-    LLINT_CALL_RETURN(exec, execCallee, codePtr.executableAddress());
+    LLINT_CALL_RETURN(execCallee, codePtr.executableAddress());
 }
 
 inline SlowPathReturnType genericCall(ExecState* exec, Instruction* pc, CodeSpecializationKind kind)
@@ -1171,22 +1110,19 @@ LLINT_SLOW_PATH_DECL(slow_path_construct)
     return genericCall(exec, pc, CodeForConstruct);
 }
 
-LLINT_SLOW_PATH_DECL(slow_path_size_frame_for_varargs)
+LLINT_SLOW_PATH_DECL(slow_path_size_and_alloc_frame_for_varargs)
 {
     LLINT_BEGIN();
     // This needs to:
     // - Set up a call frame while respecting the variable arguments.
     
-    unsigned numUsedStackSlots = -pc[5].u.operand;
-    unsigned length = sizeFrameForVarargs(exec, &vm.interpreter->stack(),
-        LLINT_OP_C(4).jsValue(), numUsedStackSlots, pc[6].u.operand);
-    LLINT_CALL_CHECK_EXCEPTION(exec, exec);
+    ExecState* execCallee = sizeAndAllocFrameForVarargs(exec, &vm.interpreter->stack(),
+        LLINT_OP_C(4).jsValue(), pc[5].u.operand);
+    LLINT_CALL_CHECK_EXCEPTION(exec);
     
-    ExecState* execCallee = calleeFrameForVarargs(exec, numUsedStackSlots, length + 1);
-    vm.varargsLength = length;
     vm.newCallFrameReturnValue = execCallee;
 
-    LLINT_RETURN_CALLEE_FRAME(execCallee);
+    LLINT_END();
 }
 
 LLINT_SLOW_PATH_DECL(slow_path_call_varargs)
@@ -1200,8 +1136,8 @@ LLINT_SLOW_PATH_DECL(slow_path_call_varargs)
     
     ExecState* execCallee = vm.newCallFrameReturnValue;
 
-    setupVarargsFrameAndSetThis(exec, execCallee, LLINT_OP_C(3).jsValue(), LLINT_OP_C(4).jsValue(), pc[6].u.operand, vm.varargsLength);
-    LLINT_CALL_CHECK_EXCEPTION(exec, exec);
+    loadVarargs(exec, execCallee, LLINT_OP_C(3).jsValue(), LLINT_OP_C(4).jsValue());
+    LLINT_CALL_CHECK_EXCEPTION(exec);
     
     execCallee->uncheckedR(JSStack::Callee) = calleeAsValue;
     execCallee->setCallerFrame(exec);
@@ -1209,28 +1145,7 @@ LLINT_SLOW_PATH_DECL(slow_path_call_varargs)
     
     return setUpCall(execCallee, pc, CodeForCall, calleeAsValue);
 }
-    
-LLINT_SLOW_PATH_DECL(slow_path_construct_varargs)
-{
-    LLINT_BEGIN_NO_SET_PC();
-    // This needs to:
-    // - Figure out what to call and compile it if necessary.
-    // - Return a tuple of machine code address to call and the new call frame.
-    
-    JSValue calleeAsValue = LLINT_OP_C(2).jsValue();
-    
-    ExecState* execCallee = vm.newCallFrameReturnValue;
-    
-    setupVarargsFrameAndSetThis(exec, execCallee, LLINT_OP_C(3).jsValue(), LLINT_OP_C(4).jsValue(), pc[6].u.operand, vm.varargsLength);
-    LLINT_CALL_CHECK_EXCEPTION(exec, exec);
-    
-    execCallee->uncheckedR(JSStack::Callee) = calleeAsValue;
-    execCallee->setCallerFrame(exec);
-    exec->setCurrentVPC(pc);
-    
-    return setUpCall(execCallee, pc, CodeForConstruct, calleeAsValue);
-}
-    
+
 LLINT_SLOW_PATH_DECL(slow_path_call_eval)
 {
     LLINT_BEGIN_NO_SET_PC();
@@ -1241,6 +1156,7 @@ LLINT_SLOW_PATH_DECL(slow_path_call_eval)
     execCallee->setArgumentCountIncludingThis(pc[3].u.operand);
     execCallee->setCallerFrame(exec);
     execCallee->uncheckedR(JSStack::Callee) = calleeAsValue;
+    execCallee->setScope(exec->scope());
     execCallee->setReturnPC(LLInt::getCodePtr(llint_generic_return_point));
     execCallee->setCodeBlock(0);
     exec->setCurrentVPC(pc);
@@ -1249,7 +1165,27 @@ LLINT_SLOW_PATH_DECL(slow_path_call_eval)
         return setUpCall(execCallee, pc, CodeForCall, calleeAsValue);
     
     vm.hostCallReturnValue = eval(execCallee);
-    LLINT_CALL_RETURN(exec, execCallee, LLInt::getCodePtr(getHostCallReturnValue));
+    LLINT_CALL_RETURN(execCallee, LLInt::getCodePtr(getHostCallReturnValue));
+}
+
+LLINT_SLOW_PATH_DECL(slow_path_tear_off_activation)
+{
+    LLINT_BEGIN();
+    ASSERT(exec->codeBlock()->needsFullScopeChain());
+    jsCast<JSActivation*>(LLINT_OP(1).jsValue())->tearOff(vm);
+    LLINT_END();
+}
+
+LLINT_SLOW_PATH_DECL(slow_path_tear_off_arguments)
+{
+    LLINT_BEGIN();
+    ASSERT(exec->codeBlock()->usesArguments());
+    Arguments* arguments = jsCast<Arguments*>(exec->uncheckedR(unmodifiedArgumentsRegister(VirtualRegister(pc[1].u.operand)).offset()).jsValue());
+    if (JSValue activationValue = LLINT_OP_C(2).jsValue())
+        arguments->didTearOffActivation(exec, jsCast<JSActivation*>(activationValue));
+    else
+        arguments->tearOff(exec);
+    LLINT_END();
 }
 
 LLINT_SLOW_PATH_DECL(slow_path_strcat)
@@ -1264,6 +1200,70 @@ LLINT_SLOW_PATH_DECL(slow_path_to_primitive)
     LLINT_RETURN(LLINT_OP_C(2).jsValue().toPrimitive(exec));
 }
 
+LLINT_SLOW_PATH_DECL(slow_path_get_pnames)
+{
+    LLINT_BEGIN();
+    JSValue v = LLINT_OP(2).jsValue();
+    if (v.isUndefinedOrNull()) {
+        pc += pc[5].u.operand;
+        LLINT_END();
+    }
+    
+    JSObject* o = v.toObject(exec);
+    Structure* structure = o->structure();
+    JSPropertyNameIterator* jsPropertyNameIterator = structure->enumerationCache();
+    if (!jsPropertyNameIterator || jsPropertyNameIterator->cachedPrototypeChain() != structure->prototypeChain(exec))
+        jsPropertyNameIterator = JSPropertyNameIterator::create(exec, o);
+    
+    LLINT_OP(1) = JSValue(jsPropertyNameIterator);
+    LLINT_OP(2) = JSValue(o);
+    LLINT_OP(3) = Register::withInt(0);
+    LLINT_OP(4) = Register::withInt(jsPropertyNameIterator->size());
+    
+    pc += OPCODE_LENGTH(op_get_pnames);
+    LLINT_END();
+}
+
+LLINT_SLOW_PATH_DECL(slow_path_next_pname)
+{
+    LLINT_BEGIN();
+    JSObject* base = asObject(LLINT_OP(2).jsValue());
+    JSString* property = asString(LLINT_OP(1).jsValue());
+    if (base->hasProperty(exec, Identifier(exec, property->value(exec)))) {
+        // Go to target.
+        pc += pc[6].u.operand;
+    } // Else, don't change the PC, so the interpreter will reloop.
+    LLINT_END();
+}
+
+LLINT_SLOW_PATH_DECL(slow_path_push_with_scope)
+{
+    LLINT_BEGIN();
+    JSValue v = LLINT_OP_C(1).jsValue();
+    JSObject* o = v.toObject(exec);
+    LLINT_CHECK_EXCEPTION();
+    
+    exec->setScope(JSWithScope::create(exec, o));
+    
+    LLINT_END();
+}
+
+LLINT_SLOW_PATH_DECL(slow_path_pop_scope)
+{
+    LLINT_BEGIN();
+    exec->setScope(exec->scope()->next());
+    LLINT_END();
+}
+
+LLINT_SLOW_PATH_DECL(slow_path_push_name_scope)
+{
+    LLINT_BEGIN();
+    CodeBlock* codeBlock = exec->codeBlock();
+    JSNameScope* scope = JSNameScope::create(exec, codeBlock->identifier(pc[1].u.operand), LLINT_OP(2).jsValue(), pc[3].u.operand);
+    exec->setScope(scope);
+    LLINT_END();
+}
+
 LLINT_SLOW_PATH_DECL(slow_path_throw)
 {
     LLINT_BEGIN();
@@ -1273,20 +1273,16 @@ LLINT_SLOW_PATH_DECL(slow_path_throw)
 LLINT_SLOW_PATH_DECL(slow_path_throw_static_error)
 {
     LLINT_BEGIN();
-    JSValue errorMessageValue = LLINT_OP_C(1).jsValue();
-    RELEASE_ASSERT(errorMessageValue.isString());
-    String errorMessage = asString(errorMessageValue)->value(exec);
     if (pc[2].u.operand)
-        LLINT_THROW(createReferenceError(exec, errorMessage));
+        LLINT_THROW(createReferenceError(exec, errorDescriptionForValue(exec, LLINT_OP_C(1).jsValue())->value(exec)));
     else
-        LLINT_THROW(createTypeError(exec, errorMessage));
+        LLINT_THROW(createTypeError(exec, errorDescriptionForValue(exec, LLINT_OP_C(1).jsValue())->value(exec)));
 }
 
 LLINT_SLOW_PATH_DECL(slow_path_handle_watchdog_timer)
 {
     LLINT_BEGIN_NO_SET_PC();
-    ASSERT(vm.watchdog);
-    if (UNLIKELY(vm.shouldTriggerTermination(exec)))
+    if (UNLIKELY(vm.watchdog.didFire(exec)))
         LLINT_THROW(createTerminatedExecutionException(&vm));
     LLINT_RETURN_TWO(0, exec);
 }
@@ -1316,25 +1312,31 @@ LLINT_SLOW_PATH_DECL(slow_path_profile_did_call)
     LLINT_END();
 }
 
+LLINT_SLOW_PATH_DECL(throw_from_native_call)
+{
+    LLINT_BEGIN();
+    ASSERT(vm.exception());
+    LLINT_END();
+}
+
 LLINT_SLOW_PATH_DECL(slow_path_handle_exception)
 {
     LLINT_BEGIN_NO_SET_PC();
-    genericUnwind(&vm, exec);
+    ASSERT(vm.exception());
+    genericUnwind(&vm, exec, vm.exception());
     LLINT_END_IMPL();
 }
 
 LLINT_SLOW_PATH_DECL(slow_path_resolve_scope)
 {
     LLINT_BEGIN();
-    const Identifier& ident = exec->codeBlock()->identifier(pc[3].u.operand);
-    JSScope* scope = LLINT_OP(2).Register::scope();
-    LLINT_RETURN(JSScope::resolve(exec, scope, ident));
+    const Identifier& ident = exec->codeBlock()->identifier(pc[2].u.operand);
+    LLINT_RETURN(JSScope::resolve(exec, exec->scope(), ident));
 }
 
 LLINT_SLOW_PATH_DECL(slow_path_get_from_scope)
 {
     LLINT_BEGIN();
-
     const Identifier& ident = exec->codeBlock()->identifier(pc[3].u.operand);
     JSObject* scope = jsCast<JSObject*>(LLINT_OP(2).jsValue());
     ResolveModeAndType modeAndType(pc[4].u.operand);
@@ -1350,13 +1352,9 @@ LLINT_SLOW_PATH_DECL(slow_path_get_from_scope)
     if (slot.isCacheableValue() && slot.slotBase() == scope && scope->structure()->propertyAccessesAreCacheable()) {
         if (modeAndType.type() == GlobalProperty || modeAndType.type() == GlobalPropertyWithVarInjectionChecks) {
             CodeBlock* codeBlock = exec->codeBlock();
-            Structure* structure = scope->structure(vm);
-            {
-                ConcurrentJITLocker locker(codeBlock->m_lock);
-                pc[5].u.structure.set(exec->vm(), codeBlock->ownerExecutable(), structure);
-                pc[6].u.operand = slot.cachedOffset();
-            }
-            structure->startWatchingPropertyForReplacements(vm, slot.cachedOffset());
+            ConcurrentJITLocker locker(codeBlock->m_lock);
+            pc[5].u.structure.set(exec->vm(), codeBlock->ownerExecutable(), scope->structure());
+            pc[6].u.operand = slot.cachedOffset();
         }
     }
 
@@ -1366,61 +1364,35 @@ LLINT_SLOW_PATH_DECL(slow_path_get_from_scope)
 LLINT_SLOW_PATH_DECL(slow_path_put_to_scope)
 {
     LLINT_BEGIN();
-
     CodeBlock* codeBlock = exec->codeBlock();
     const Identifier& ident = codeBlock->identifier(pc[2].u.operand);
     JSObject* scope = jsCast<JSObject*>(LLINT_OP(1).jsValue());
     JSValue value = LLINT_OP_C(3).jsValue();
     ResolveModeAndType modeAndType = ResolveModeAndType(pc[4].u.operand);
-    if (modeAndType.type() == LocalClosureVar) {
-        JSLexicalEnvironment* environment = jsCast<JSLexicalEnvironment*>(scope);
-        environment->variableAt(ScopeOffset(pc[6].u.operand)).set(vm, environment, value);
-        
-        // Have to do this *after* the write, because if this puts the set into IsWatched, then we need
-        // to have already changed the value of the variable. Otherwise we might watch and constant-fold
-        // to the Undefined value from before the assignment.
-        if (WatchpointSet* set = pc[5].u.watchpointSet)
-            set->touch("Executed op_put_scope<LocalClosureVar>");
-        LLINT_END();
-    }
 
     if (modeAndType.mode() == ThrowIfNotFound && !scope->hasProperty(exec, ident))
         LLINT_THROW(createUndefinedVariableError(exec, ident));
 
     PutPropertySlot slot(scope, codeBlock->isStrictMode());
     scope->methodTable()->put(scope, exec, ident, value, slot);
-    
-    CommonSlowPaths::tryCachePutToScopeGlobal(exec, codeBlock, pc, scope, modeAndType, slot);
-
-    LLINT_END();
-}
-
-extern "C" SlowPathReturnType llint_throw_stack_overflow_error(VM* vm, ProtoCallFrame* protoFrame)
-{
-    ExecState* exec = vm->topCallFrame;
-    if (!exec)
-        exec = protoFrame->callee()->globalObject()->globalExec();
-    throwStackOverflowError(exec);
-    return encodeResult(0, 0);
-}
 
-#if !ENABLE(JIT)
-extern "C" SlowPathReturnType llint_stack_check_at_vm_entry(VM* vm, Register* newTopOfStack)
-{
-    bool success = vm->interpreter->stack().ensureCapacityFor(newTopOfStack);
-    return encodeResult(reinterpret_cast<void*>(success), 0);
-}
-#endif
+    // Covers implicit globals. Since they don't exist until they first execute, we didn't know how to cache them at compile time.
+    if (modeAndType.type() == GlobalProperty || modeAndType.type() == GlobalPropertyWithVarInjectionChecks) {
+        if (slot.isCacheable() && slot.base() == scope && scope->structure()->propertyAccessesAreCacheable()) {
+            ConcurrentJITLocker locker(codeBlock->m_lock);
+            pc[5].u.structure.set(exec->vm(), codeBlock->ownerExecutable(), scope->structure());
+            pc[6].u.operand = slot.cachedOffset();
+        }
+    }
 
-extern "C" void llint_write_barrier_slow(ExecState* exec, JSCell* cell)
-{
-    VM& vm = exec->vm();
-    vm.heap.writeBarrier(cell);
+    LLINT_END();
 }
 
-extern "C" NO_RETURN_DUE_TO_CRASH void llint_crash()
+extern "C" void llint_write_barrier_slow(ExecState*, JSCell* cell)
 {
-    CRASH();
+    Heap::writeBarrier(cell);
 }
 
 } } // namespace JSC::LLInt
+
+#endif // ENABLE(LLINT)