X-Git-Url: https://git.saurik.com/apple/javascriptcore.git/blobdiff_plain/f9bf01c6616d5ddcf65b13b33cedf9e387ff7a63..ed1e77d3adeb83d26fd1dfb16dd84cabdcefd250:/bytecompiler/NodesCodegen.cpp

diff --git a/bytecompiler/NodesCodegen.cpp b/bytecompiler/NodesCodegen.cpp
index b66c50d..cfd3ef1 100644
--- a/bytecompiler/NodesCodegen.cpp
+++ b/bytecompiler/NodesCodegen.cpp
@@ -1,10 +1,11 @@
 /*
 *  Copyright (C) 1999-2002 Harri Porten (porten@kde.org)
 *  Copyright (C) 2001 Peter Kelly (pmk@post.com)
-*  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
+*  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012, 2013, 2015 Apple Inc. All rights reserved.
 *  Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca)
 *  Copyright (C) 2007 Maks Orlovich
 *  Copyright (C) 2007 Eric Seidel <eric@webkit.org>
+ * Copyright (C) 2012 Igalia, S.L.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Library General Public
@@ -27,20 +28,26 @@
 #include "Nodes.h"
 #include "NodeConstructors.h"
 
+#include "BuiltinNames.h"
 #include "BytecodeGenerator.h"
 #include "CallFrame.h"
 #include "Debugger.h"
 #include "JIT.h"
 #include "JSFunction.h"
 #include "JSGlobalObject.h"
-#include "JSStaticScopeObject.h"
+#include "JSNameScope.h"
+#include "JSONObject.h"
 #include "LabelScope.h"
 #include "Lexer.h"
-#include "Operations.h"
+#include "JSCInlines.h"
+#include "JSTemplateRegistryKey.h"
 #include "Parser.h"
 #include "PropertyNameArray.h"
+#include "RegExpCache.h"
 #include "RegExpObject.h"
 #include "SamplingTool.h"
+#include "StackAlignment.h"
+#include "TemplateRegistryKey.h"
 #include <wtf/Assertions.h>
 #include <wtf/RefCountedLeakCounter.h>
 #include <wtf/Threading.h>
@@ -72,113 +79,251 @@ namespace JSC {
     because the assignment node, "x =", passes r[x] as dst to the number node, "1".
 */
 
-// ------------------------------ ThrowableExpressionData --------------------------------
-
-static void substitute(UString& string, const UString& substring)
+void ExpressionNode::emitBytecodeInConditionContext(BytecodeGenerator& generator, Label* trueTarget, Label* falseTarget, FallThroughMode fallThroughMode)
 {
-    int position = string.find("%s");
-    ASSERT(position != -1);
-    string = makeString(string.substr(0, position), substring, string.substr(position + 2));
+    RegisterID* result = generator.emitNode(this);
+    if (fallThroughMode == FallThroughMeansTrue)
+        generator.emitJumpIfFalse(result, falseTarget);
+    else
+        generator.emitJumpIfTrue(result, trueTarget);
 }
 
-RegisterID* ThrowableExpressionData::emitThrowError(BytecodeGenerator& generator, ErrorType type, const char* message)
-{
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    RegisterID* exception = generator.emitNewError(generator.newTemporary(), type, jsString(generator.globalData(), message));
-    generator.emitThrow(exception);
-    return exception;
-}
+// ------------------------------ ThrowableExpressionData --------------------------------
 
-RegisterID* ThrowableExpressionData::emitThrowError(BytecodeGenerator& generator, ErrorType type, const char* messageTemplate, const UString& label)
+RegisterID* ThrowableExpressionData::emitThrowReferenceError(BytecodeGenerator& generator, const String& message)
 {
-    UString message = messageTemplate;
-    substitute(message, label);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    RegisterID* exception = generator.emitNewError(generator.newTemporary(), type, jsString(generator.globalData(), message));
-    generator.emitThrow(exception);
-    return exception;
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    generator.emitThrowReferenceError(message);
+    return generator.newTemporary();
 }
 
-inline RegisterID* ThrowableExpressionData::emitThrowError(BytecodeGenerator& generator, ErrorType type, const char* messageTemplate, const Identifier& label)
+// ------------------------------ ConstantNode ----------------------------------
+
+void ConstantNode::emitBytecodeInConditionContext(BytecodeGenerator& generator, Label* trueTarget, Label* falseTarget, FallThroughMode fallThroughMode)
 {
-    return emitThrowError(generator, type, messageTemplate, label.ustring());
-}
+    TriState value = jsValue(generator).pureToBoolean();
+    if (value == MixedTriState)
+        ExpressionNode::emitBytecodeInConditionContext(generator, trueTarget, falseTarget, fallThroughMode);
+    else if (value == TrueTriState && fallThroughMode == FallThroughMeansFalse)
+        generator.emitJump(trueTarget);
+    else if (value == FalseTriState && fallThroughMode == FallThroughMeansTrue)
+        generator.emitJump(falseTarget);
 
-// ------------------------------ NullNode -------------------------------------
+    // All other cases are unconditional fall-throughs, like "if (true)".
+}
 
-RegisterID* NullNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* ConstantNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     if (dst == generator.ignoredResult())
         return 0;
-    return generator.emitLoad(dst, jsNull());
+    return generator.emitLoad(dst, jsValue(generator));
 }
 
-// ------------------------------ BooleanNode ----------------------------------
-
-RegisterID* BooleanNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+JSValue StringNode::jsValue(BytecodeGenerator& generator) const
 {
-    if (dst == generator.ignoredResult())
-        return 0;
-    return generator.emitLoad(dst, m_value);
+    return generator.addStringConstant(m_value);
 }
 
-// ------------------------------ NumberNode -----------------------------------
+// ------------------------------ NumberNode ----------------------------------
 
 RegisterID* NumberNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     if (dst == generator.ignoredResult())
-        return 0;
-    return generator.emitLoad(dst, m_value);
+        return nullptr;
+    return generator.emitLoad(dst, jsValue(generator), isIntegerNode() ? SourceCodeRepresentation::Integer : SourceCodeRepresentation::Double);
 }
 
-// ------------------------------ StringNode -----------------------------------
+// ------------------------------ RegExpNode -----------------------------------
 
-RegisterID* StringNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* RegExpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     if (dst == generator.ignoredResult())
         return 0;
-    return generator.emitLoad(dst, m_value);
+    return generator.emitNewRegExp(generator.finalDestination(dst), RegExp::create(*generator.vm(), m_pattern.string(), regExpFlags(m_flags.string())));
 }
 
-// ------------------------------ RegExpNode -----------------------------------
+// ------------------------------ ThisNode -------------------------------------
 
-RegisterID* RegExpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* ThisNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegExp> regExp = RegExp::create(generator.globalData(), m_pattern.ustring(), m_flags.ustring());
-    if (!regExp->isValid())
-        return emitThrowError(generator, SyntaxError, "Invalid regular expression: %s", regExp->errorMessage());
+    if (m_shouldAlwaysEmitTDZCheck || generator.constructorKind() == ConstructorKind::Derived)
+        generator.emitTDZCheck(generator.thisRegister());
+
     if (dst == generator.ignoredResult())
         return 0;
-    return generator.emitNewRegExp(generator.finalDestination(dst), regExp.get());
+
+    RegisterID* result = generator.moveToDestinationIfNeeded(dst, generator.thisRegister());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(generator.thisRegister(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        static const unsigned thisLength = 4;
+        generator.emitTypeProfilerExpressionInfo(position(), JSTextPosition(-1, position().offset + thisLength, -1));
+    }
+    return result;
 }
 
-// ------------------------------ ThisNode -------------------------------------
+// ------------------------------ SuperNode -------------------------------------
 
-RegisterID* ThisNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* SuperNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     if (dst == generator.ignoredResult())
         return 0;
-    return generator.moveToDestinationIfNeeded(dst, generator.thisRegister());
+
+    RegisterID callee;
+    callee.setIndex(JSStack::Callee);
+
+    RefPtr<RegisterID> homeObject = generator.emitGetById(generator.newTemporary(), &callee, generator.propertyNames().homeObjectPrivateName);
+    RefPtr<RegisterID> protoParent = generator.emitGetById(generator.newTemporary(), homeObject.get(), generator.propertyNames().underscoreProto);
+    return generator.emitGetById(generator.finalDestination(dst), protoParent.get(), generator.propertyNames().constructor);
+}
+
+static RegisterID* emitSuperBaseForCallee(BytecodeGenerator& generator)
+{
+    RegisterID callee;
+    callee.setIndex(JSStack::Callee);
+
+    RefPtr<RegisterID> homeObject = generator.emitGetById(generator.newTemporary(), &callee, generator.propertyNames().homeObjectPrivateName);
+    return generator.emitGetById(generator.newTemporary(), homeObject.get(), generator.propertyNames().underscoreProto);
 }
 
 // ------------------------------ ResolveNode ----------------------------------
 
 bool ResolveNode::isPure(BytecodeGenerator& generator) const
 {
-    return generator.isLocal(m_ident);
+    return generator.variable(m_ident).offset().isStack();
 }
 
 RegisterID* ResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (RegisterID* local = generator.registerFor(m_ident)) {
+    Variable var = generator.variable(m_ident);
+    if (RegisterID* local = var.local()) {
         if (dst == generator.ignoredResult())
-            return 0;
+            return nullptr;
+        if (generator.vm()->typeProfiler()) {
+            generator.emitProfileType(local, ProfileTypeBytecodeHasGlobalID, nullptr);
+            generator.emitTypeProfilerExpressionInfo(m_position, JSTextPosition(-1, m_position.offset + m_ident.length(), -1));
+        }
         return generator.moveToDestinationIfNeeded(dst, local);
     }
     
-    generator.emitExpressionInfo(m_startOffset + m_ident.size(), m_ident.size(), 0);
-    return generator.emitResolve(generator.finalDestination(dst), m_ident);
+    JSTextPosition divot = m_start + m_ident.length();
+    generator.emitExpressionInfo(divot, m_start, divot);
+    RefPtr<RegisterID> scope = generator.emitResolveScope(dst, var);
+    RegisterID* finalDest = generator.finalDestination(dst);
+    RegisterID* result = generator.emitGetFromScope(finalDest, scope.get(), var, ThrowIfNotFound);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(finalDest, var.isResolved() ? ProfileTypeBytecodeGetFromLocalScope : ProfileTypeBytecodeGetFromScope, &m_ident);
+        generator.emitTypeProfilerExpressionInfo(m_position, JSTextPosition(-1, m_position.offset + m_ident.length(), -1));
+    }
+    return result;
+}
+
+#if ENABLE(ES6_TEMPLATE_LITERAL_SYNTAX)
+// ------------------------------ TemplateStringNode -----------------------------------
+
+RegisterID* TemplateStringNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    if (dst == generator.ignoredResult())
+        return nullptr;
+    return generator.emitLoad(dst, JSValue(generator.addStringConstant(cooked())));
+}
+
+// ------------------------------ TemplateLiteralNode -----------------------------------
+
+RegisterID* TemplateLiteralNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    if (!m_templateExpressions) {
+        TemplateStringNode* templateString = m_templateStrings->value();
+        ASSERT_WITH_MESSAGE(!m_templateStrings->next(), "Only one template element exists because there's no expression in a given template literal.");
+        return generator.emitNode(dst, templateString);
+    }
+
+    Vector<RefPtr<RegisterID>, 16> temporaryRegisters;
+
+    TemplateStringListNode* templateString = m_templateStrings;
+    TemplateExpressionListNode* templateExpression = m_templateExpressions;
+    for (; templateExpression; templateExpression = templateExpression->next(), templateString = templateString->next()) {
+        // Evaluate TemplateString.
+        if (!templateString->value()->cooked().isEmpty()) {
+            temporaryRegisters.append(generator.newTemporary());
+            generator.emitNode(temporaryRegisters.last().get(), templateString->value());
+        }
+
+        // Evaluate Expression.
+        temporaryRegisters.append(generator.newTemporary());
+        generator.emitNode(temporaryRegisters.last().get(), templateExpression->value());
+        generator.emitToString(temporaryRegisters.last().get(), temporaryRegisters.last().get());
+    }
+
+    // Evaluate tail TemplateString.
+    if (!templateString->value()->cooked().isEmpty()) {
+        temporaryRegisters.append(generator.newTemporary());
+        generator.emitNode(temporaryRegisters.last().get(), templateString->value());
+    }
+
+    return generator.emitStrcat(generator.finalDestination(dst, temporaryRegisters[0].get()), temporaryRegisters[0].get(), temporaryRegisters.size());
+}
+
+// ------------------------------ TaggedTemplateNode -----------------------------------
+
+RegisterID* TaggedTemplateNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    ExpectedFunction expectedFunction = NoExpectedFunction;
+    RefPtr<RegisterID> tag = nullptr;
+    RefPtr<RegisterID> base = nullptr;
+    if (!m_tag->isLocation()) {
+        tag = generator.newTemporary();
+        tag = generator.emitNode(tag.get(), m_tag);
+    } else if (m_tag->isResolveNode()) {
+        ResolveNode* resolve = static_cast<ResolveNode*>(m_tag);
+        const Identifier& identifier = resolve->identifier();
+        expectedFunction = generator.expectedFunctionForIdentifier(identifier);
+
+        Variable var = generator.variable(identifier);
+        if (RegisterID* local = var.local())
+            tag = generator.emitMove(generator.newTemporary(), local);
+        else {
+            tag = generator.newTemporary();
+            base = generator.newTemporary();
+
+            JSTextPosition newDivot = divotStart() + identifier.length();
+            generator.emitExpressionInfo(newDivot, divotStart(), newDivot);
+            generator.moveToDestinationIfNeeded(base.get(), generator.emitResolveScope(base.get(), var));
+            generator.emitGetFromScope(tag.get(), base.get(), var, ThrowIfNotFound);
+        }
+    } else if (m_tag->isBracketAccessorNode()) {
+        BracketAccessorNode* bracket = static_cast<BracketAccessorNode*>(m_tag);
+        base = generator.newTemporary();
+        base = generator.emitNode(base.get(), bracket->base());
+        RefPtr<RegisterID> property = generator.emitNode(bracket->subscript());
+        tag = generator.emitGetByVal(generator.newTemporary(), base.get(), property.get());
+    } else {
+        ASSERT(m_tag->isDotAccessorNode());
+        DotAccessorNode* dot = static_cast<DotAccessorNode*>(m_tag);
+        base = generator.newTemporary();
+        base = generator.emitNode(base.get(), dot->base());
+        tag = generator.emitGetById(generator.newTemporary(), base.get(), dot->identifier());
+    }
+
+    RefPtr<RegisterID> templateObject = generator.emitGetTemplateObject(generator.newTemporary(), this);
+
+    unsigned expressionsCount = 0;
+    for (TemplateExpressionListNode* templateExpression = m_templateLiteral->templateExpressions(); templateExpression; templateExpression = templateExpression->next())
+        ++expressionsCount;
+
+    CallArguments callArguments(generator, nullptr, 1 + expressionsCount);
+    if (base)
+        generator.emitMove(callArguments.thisRegister(), base.get());
+    else
+        generator.emitLoad(callArguments.thisRegister(), jsUndefined());
+
+    unsigned argumentIndex = 0;
+    generator.emitMove(callArguments.argumentRegister(argumentIndex++), templateObject.get());
+    for (TemplateExpressionListNode* templateExpression = m_templateLiteral->templateExpressions(); templateExpression; templateExpression = templateExpression->next())
+        generator.emitNode(callArguments.argumentRegister(argumentIndex++), templateExpression->value());
+
+    return generator.emitCall(generator.finalDestination(dst, tag.get()), tag.get(), expectedFunction, callArguments, divot(), divotStart(), divotEnd());
 }
+#endif
 
 // ------------------------------ ArrayNode ------------------------------------
 
@@ -189,28 +334,55 @@ RegisterID* ArrayNode::emitBytecode(BytecodeGenerator& generator, RegisterID* ds
     unsigned length = 0;
     ElementNode* firstPutElement;
     for (firstPutElement = m_element; firstPutElement; firstPutElement = firstPutElement->next()) {
-        if (firstPutElement->elision())
+        if (firstPutElement->elision() || firstPutElement->value()->isSpreadExpression())
             break;
         ++length;
     }
 
     if (!firstPutElement && !m_elision)
-        return generator.emitNewArray(generator.finalDestination(dst), m_element);
-
-    RefPtr<RegisterID> array = generator.emitNewArray(generator.tempDestination(dst), m_element);
+        return generator.emitNewArray(generator.finalDestination(dst), m_element, length);
 
-    for (ElementNode* n = firstPutElement; n; n = n->next()) {
+    RefPtr<RegisterID> array = generator.emitNewArray(generator.tempDestination(dst), m_element, length);
+    ElementNode* n = firstPutElement;
+    for (; n; n = n->next()) {
+        if (n->value()->isSpreadExpression())
+            goto handleSpread;
         RegisterID* value = generator.emitNode(n->value());
         length += n->elision();
         generator.emitPutByIndex(array.get(), length++, value);
     }
 
     if (m_elision) {
-        RegisterID* value = generator.emitLoad(0, jsNumber(generator.globalData(), m_elision + length));
+        RegisterID* value = generator.emitLoad(0, jsNumber(m_elision + length));
         generator.emitPutById(array.get(), generator.propertyNames().length, value);
     }
 
     return generator.moveToDestinationIfNeeded(dst, array.get());
+    
+handleSpread:
+    RefPtr<RegisterID> index = generator.emitLoad(generator.newTemporary(), jsNumber(length));
+    auto spreader = [this, array, index](BytecodeGenerator& generator, RegisterID* value)
+    {
+        generator.emitDirectPutByVal(array.get(), index.get(), value);
+        generator.emitInc(index.get());
+    };
+    for (; n; n = n->next()) {
+        if (n->elision())
+            generator.emitBinaryOp(op_add, index.get(), index.get(), generator.emitLoad(0, jsNumber(n->elision())), OperandTypes(ResultType::numberTypeIsInt32(), ResultType::numberTypeIsInt32()));
+        if (n->value()->isSpreadExpression()) {
+            SpreadExpressionNode* spread = static_cast<SpreadExpressionNode*>(n->value());
+            generator.emitEnumeration(spread, spread->expression(), spreader);
+        } else {
+            generator.emitDirectPutByVal(array.get(), index.get(), generator.emitNode(n->value()));
+            generator.emitInc(index.get());
+        }
+    }
+    
+    if (m_elision) {
+        generator.emitBinaryOp(op_add, index.get(), index.get(), generator.emitLoad(0, jsNumber(m_elision)), OperandTypes(ResultType::numberTypeIsInt32(), ResultType::numberTypeIsInt32()));
+        generator.emitPutById(array.get(), generator.propertyNames().length, index.get());
+    }
+    return generator.moveToDestinationIfNeeded(dst, array.get());
 }
 
 bool ArrayNode::isSimpleArray() const
@@ -224,18 +396,21 @@ bool ArrayNode::isSimpleArray() const
     return true;
 }
 
-ArgumentListNode* ArrayNode::toArgumentList(JSGlobalData* globalData) const
+ArgumentListNode* ArrayNode::toArgumentList(ParserArena& parserArena, int lineNumber, int startPosition) const
 {
     ASSERT(!m_elision && !m_optional);
     ElementNode* ptr = m_element;
     if (!ptr)
         return 0;
-    ArgumentListNode* head = new (globalData) ArgumentListNode(globalData, ptr->value());
+    JSTokenLocation location;
+    location.line = lineNumber;
+    location.startOffset = startPosition;
+    ArgumentListNode* head = new (parserArena) ArgumentListNode(location, ptr->value());
     ArgumentListNode* tail = head;
     ptr = ptr->next();
     for (; ptr; ptr = ptr->next()) {
         ASSERT(!ptr->elision());
-        tail = new (globalData) ArgumentListNode(globalData, tail, ptr->value());
+        tail = new (parserArena) ArgumentListNode(location, tail, ptr->value());
     }
     return head;
 }
@@ -244,63 +419,218 @@ ArgumentListNode* ArrayNode::toArgumentList(JSGlobalData* globalData) const
 
 RegisterID* ObjectLiteralNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-     if (!m_list) {
-         if (dst == generator.ignoredResult())
-             return 0;
-         return generator.emitNewObject(generator.finalDestination(dst));
-     }
-     return generator.emitNode(dst, m_list);
+    if (!m_list) {
+        if (dst == generator.ignoredResult())
+            return 0;
+        return generator.emitNewObject(generator.finalDestination(dst));
+    }
+    RefPtr<RegisterID> newObj = generator.emitNewObject(generator.tempDestination(dst));
+    generator.emitNode(newObj.get(), m_list);
+    return generator.moveToDestinationIfNeeded(dst, newObj.get());
 }
 
 // ------------------------------ PropertyListNode -----------------------------
 
+static inline void emitPutHomeObject(BytecodeGenerator& generator, RegisterID* function, RegisterID* homeObject)
+{
+    generator.emitPutById(function, generator.propertyNames().homeObjectPrivateName, homeObject);
+}
+
 RegisterID* PropertyListNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> newObj = generator.tempDestination(dst);
-    
-    generator.emitNewObject(newObj.get());
-    
-    for (PropertyListNode* p = this; p; p = p->m_next) {
-        RegisterID* value = generator.emitNode(p->m_node->m_assign);
-        
-        switch (p->m_node->m_type) {
-            case PropertyNode::Constant: {
-                generator.emitPutById(newObj.get(), p->m_node->name(), value);
+    // Fast case: this loop just handles regular value properties.
+    PropertyListNode* p = this;
+    for (; p && (p->m_node->m_type & PropertyNode::Constant); p = p->m_next)
+        emitPutConstantProperty(generator, dst, *p->m_node);
+
+    // Were there any get/set properties?
+    if (p) {
+        // Build a list of getter/setter pairs to try to put them at the same time. If we encounter
+        // a computed property, just emit everything as that may override previous values.
+        bool hasComputedProperty = false;
+
+        typedef std::pair<PropertyNode*, PropertyNode*> GetterSetterPair;
+        typedef HashMap<UniquedStringImpl*, GetterSetterPair, IdentifierRepHash> GetterSetterMap;
+        GetterSetterMap map;
+
+        // Build a map, pairing get/set values together.
+        for (PropertyListNode* q = p; q; q = q->m_next) {
+            PropertyNode* node = q->m_node;
+            if (node->m_type & PropertyNode::Computed) {
+                hasComputedProperty = true;
                 break;
             }
-            case PropertyNode::Getter: {
-                generator.emitPutGetter(newObj.get(), p->m_node->name(), value);
-                break;
+            if (node->m_type & PropertyNode::Constant)
+                continue;
+
+            // Duplicates are possible.
+            GetterSetterPair pair(node, static_cast<PropertyNode*>(nullptr));
+            GetterSetterMap::AddResult result = map.add(node->name()->impl(), pair);
+            if (!result.isNewEntry) {
+                if (result.iterator->value.first->m_type == node->m_type)
+                    result.iterator->value.first = node;
+                else
+                    result.iterator->value.second = node;
             }
-            case PropertyNode::Setter: {
-                generator.emitPutSetter(newObj.get(), p->m_node->name(), value);
-                break;
+        }
+
+        // Iterate over the remaining properties in the list.
+        for (; p; p = p->m_next) {
+            PropertyNode* node = p->m_node;
+
+            // Handle regular values.
+            if (node->m_type & PropertyNode::Constant) {
+                emitPutConstantProperty(generator, dst, *node);
+                continue;
+            }
+
+            RegisterID* value = generator.emitNode(node->m_assign);
+            bool isClassProperty = node->needsSuperBinding();
+            if (isClassProperty)
+                emitPutHomeObject(generator, value, dst);
+
+            ASSERT(node->m_type & (PropertyNode::Getter | PropertyNode::Setter));
+
+            // This is a get/set property which may be overridden by a computed property later.
+            if (hasComputedProperty) {
+                if (node->m_type & PropertyNode::Getter)
+                    generator.emitPutGetterById(dst, *node->name(), value);
+                else
+                    generator.emitPutSetterById(dst, *node->name(), value);
+                continue;
+            }
+
+            // This is a get/set property pair.
+            GetterSetterMap::iterator it = map.find(node->name()->impl());
+            ASSERT(it != map.end());
+            GetterSetterPair& pair = it->value;
+
+            // Was this already generated as a part of its partner?
+            if (pair.second == node)
+                continue;
+
+            // Generate the paired node now.
+            RefPtr<RegisterID> getterReg;
+            RefPtr<RegisterID> setterReg;
+            RegisterID* secondReg = nullptr;
+
+            if (node->m_type & PropertyNode::Getter) {
+                getterReg = value;
+                if (pair.second) {
+                    ASSERT(pair.second->m_type & PropertyNode::Setter);
+                    setterReg = generator.emitNode(pair.second->m_assign);
+                    secondReg = setterReg.get();
+                } else {
+                    setterReg = generator.newTemporary();
+                    generator.emitLoad(setterReg.get(), jsUndefined());
+                }
+            } else {
+                ASSERT(node->m_type & PropertyNode::Setter);
+                setterReg = value;
+                if (pair.second) {
+                    ASSERT(pair.second->m_type & PropertyNode::Getter);
+                    getterReg = generator.emitNode(pair.second->m_assign);
+                    secondReg = getterReg.get();
+                } else {
+                    getterReg = generator.newTemporary();
+                    generator.emitLoad(getterReg.get(), jsUndefined());
+                }
             }
-            default:
-                ASSERT_NOT_REACHED();
+
+            ASSERT(!pair.second || isClassProperty == pair.second->needsSuperBinding());
+            if (isClassProperty && pair.second)
+                emitPutHomeObject(generator, secondReg, dst);
+
+            if (isClassProperty) {
+                RefPtr<RegisterID> propertyNameRegister = generator.emitLoad(generator.newTemporary(), *node->name());
+                generator.emitCallDefineProperty(dst, propertyNameRegister.get(),
+                    nullptr, getterReg.get(), setterReg.get(), BytecodeGenerator::PropertyConfigurable, m_position);
+            } else
+                generator.emitPutGetterSetter(dst, *node->name(), getterReg.get(), setterReg.get());
         }
     }
-    
-    return generator.moveToDestinationIfNeeded(dst, newObj.get());
+
+    return dst;
+}
+
+void PropertyListNode::emitPutConstantProperty(BytecodeGenerator& generator, RegisterID* newObj, PropertyNode& node)
+{
+    RefPtr<RegisterID> value = generator.emitNode(node.m_assign);
+    if (node.needsSuperBinding()) {
+        emitPutHomeObject(generator, value.get(), newObj);
+
+        RefPtr<RegisterID> propertyNameRegister;
+        if (node.name())
+            propertyNameRegister = generator.emitLoad(generator.newTemporary(), *node.name());
+        else
+            propertyNameRegister = generator.emitNode(node.m_expression);
+
+        generator.emitCallDefineProperty(newObj, propertyNameRegister.get(),
+            value.get(), nullptr, nullptr, BytecodeGenerator::PropertyConfigurable | BytecodeGenerator::PropertyWritable, m_position);
+        return;
+    }
+    if (const auto* identifier = node.name()) {
+        Optional<uint32_t> optionalIndex = parseIndex(*identifier);
+        if (!optionalIndex) {
+            generator.emitDirectPutById(newObj, *identifier, value.get(), node.putType());
+            return;
+        }
+
+        RefPtr<RegisterID> index = generator.emitLoad(generator.newTemporary(), jsNumber(optionalIndex.value()));
+        generator.emitDirectPutByVal(newObj, index.get(), value.get());
+        return;
+    }
+    RefPtr<RegisterID> propertyName = generator.emitNode(node.m_expression);
+    generator.emitDirectPutByVal(newObj, propertyName.get(), value.get());
 }
 
 // ------------------------------ BracketAccessorNode --------------------------------
 
 RegisterID* BracketAccessorNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base, m_subscriptHasAssignments, m_subscript->isPure(generator));
-    RegisterID* property = generator.emitNode(m_subscript);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    return generator.emitGetByVal(generator.finalDestination(dst), base.get(), property);
+    if (m_base->isSuperNode()) {
+        // FIXME: Should we generate the profiler info?
+        if (m_subscript->isString()) {
+            const Identifier& id = static_cast<StringNode*>(m_subscript)->value();
+            return generator.emitGetById(generator.finalDestination(dst), emitSuperBaseForCallee(generator), id);
+        }
+        return generator.emitGetByVal(generator.finalDestination(dst), emitSuperBaseForCallee(generator), generator.emitNode(m_subscript));
+    }
+
+    RegisterID* ret;
+    RegisterID* finalDest = generator.finalDestination(dst);
+
+    if (m_subscript->isString()) {
+        RefPtr<RegisterID> base = generator.emitNode(m_base);
+        ret = generator.emitGetById(finalDest, base.get(), static_cast<StringNode*>(m_subscript)->value());
+    } else {
+        RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base, m_subscriptHasAssignments, m_subscript->isPure(generator));
+        RegisterID* property = generator.emitNode(m_subscript);
+        ret = generator.emitGetByVal(finalDest, base.get(), property);
+    }
+
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(finalDest, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return ret;
 }
 
 // ------------------------------ DotAccessorNode --------------------------------
 
 RegisterID* DotAccessorNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RegisterID* base = generator.emitNode(m_base);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    return generator.emitGetById(generator.finalDestination(dst), base, m_ident);
+    RefPtr<RegisterID> base = m_base->isSuperNode() ? emitSuperBaseForCallee(generator) : generator.emitNode(m_base);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RegisterID* finalDest = generator.finalDestination(dst);
+    RegisterID* ret = generator.emitGetById(finalDest, base.get(), m_ident);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(finalDest, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return ret;
 }
 
 // ------------------------------ ArgumentListNode -----------------------------
@@ -315,19 +645,64 @@ RegisterID* ArgumentListNode::emitBytecode(BytecodeGenerator& generator, Registe
 
 RegisterID* NewExprNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
+    ExpectedFunction expectedFunction;
+    if (m_expr->isResolveNode())
+        expectedFunction = generator.expectedFunctionForIdentifier(static_cast<ResolveNode*>(m_expr)->identifier());
+    else
+        expectedFunction = NoExpectedFunction;
     RefPtr<RegisterID> func = generator.emitNode(m_expr);
-    return generator.emitConstruct(generator.finalDestination(dst), func.get(), m_args, divot(), startOffset(), endOffset());
+    RefPtr<RegisterID> returnValue = generator.finalDestination(dst, func.get());
+    CallArguments callArguments(generator, m_args);
+    generator.emitMove(callArguments.thisRegister(), func.get());
+    return generator.emitConstruct(returnValue.get(), func.get(), expectedFunction, callArguments, divot(), divotStart(), divotEnd());
+}
+
+CallArguments::CallArguments(BytecodeGenerator& generator, ArgumentsNode* argumentsNode, unsigned additionalArguments)
+    : m_argumentsNode(argumentsNode)
+    , m_padding(0)
+{
+    if (generator.shouldEmitProfileHooks())
+        m_profileHookRegister = generator.newTemporary();
+
+    size_t argumentCountIncludingThis = 1 + additionalArguments; // 'this' register.
+    if (argumentsNode) {
+        for (ArgumentListNode* node = argumentsNode->m_listNode; node; node = node->m_next)
+            ++argumentCountIncludingThis;
+    }
+
+    m_argv.grow(argumentCountIncludingThis);
+    for (int i = argumentCountIncludingThis - 1; i >= 0; --i) {
+        m_argv[i] = generator.newTemporary();
+        ASSERT(static_cast<size_t>(i) == m_argv.size() - 1 || m_argv[i]->index() == m_argv[i + 1]->index() - 1);
+    }
+    
+    while (stackOffset() % stackAlignmentRegisters()) {
+        m_argv.insert(0, generator.newTemporary());
+        m_padding++;
+    }
 }
 
 // ------------------------------ EvalFunctionCallNode ----------------------------------
 
 RegisterID* EvalFunctionCallNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> func = generator.tempDestination(dst);
-    RefPtr<RegisterID> thisRegister = generator.newTemporary();
-    generator.emitExpressionInfo(divot() - startOffset() + 4, 4, 0);
-    generator.emitResolveWithBase(thisRegister.get(), func.get(), generator.propertyNames().eval);
-    return generator.emitCallEval(generator.finalDestination(dst, func.get()), func.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+    Variable var = generator.variable(generator.propertyNames().eval);
+    if (RegisterID* local = var.local()) {
+        RefPtr<RegisterID> func = generator.emitMove(generator.tempDestination(dst), local);
+        CallArguments callArguments(generator, m_args);
+        generator.emitLoad(callArguments.thisRegister(), jsUndefined());
+        return generator.emitCallEval(generator.finalDestination(dst, func.get()), func.get(), callArguments, divot(), divotStart(), divotEnd());
+    }
+
+    RefPtr<RegisterID> func = generator.newTemporary();
+    CallArguments callArguments(generator, m_args);
+    JSTextPosition newDivot = divotStart() + 4;
+    generator.emitExpressionInfo(newDivot, divotStart(), newDivot);
+    generator.moveToDestinationIfNeeded(
+        callArguments.thisRegister(),
+        generator.emitResolveScope(callArguments.thisRegister(), var));
+    generator.emitGetFromScope(func.get(), callArguments.thisRegister(), var, ThrowIfNotFound);
+    return generator.emitCallEval(generator.finalDestination(dst, func.get()), func.get(), callArguments, divot(), divotStart(), divotEnd());
 }
 
 // ------------------------------ FunctionCallValueNode ----------------------------------
@@ -335,46 +710,134 @@ RegisterID* EvalFunctionCallNode::emitBytecode(BytecodeGenerator& generator, Reg
 RegisterID* FunctionCallValueNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     RefPtr<RegisterID> func = generator.emitNode(m_expr);
-    RefPtr<RegisterID> thisRegister = generator.emitLoad(generator.newTemporary(), jsNull());
-    return generator.emitCall(generator.finalDestination(dst, func.get()), func.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+    RefPtr<RegisterID> returnValue = generator.finalDestination(dst, func.get());
+    CallArguments callArguments(generator, m_args);
+    if (m_expr->isSuperNode()) {
+        ASSERT(generator.isConstructor());
+        ASSERT(generator.constructorKind() == ConstructorKind::Derived);
+        generator.emitMove(callArguments.thisRegister(), generator.newTarget());
+        RegisterID* ret = generator.emitConstruct(returnValue.get(), func.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+        generator.emitMove(generator.thisRegister(), ret);
+        return ret;
+    }
+    generator.emitLoad(callArguments.thisRegister(), jsUndefined());
+    RegisterID* ret = generator.emitCall(returnValue.get(), func.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(returnValue.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return ret;
 }
 
 // ------------------------------ FunctionCallResolveNode ----------------------------------
 
 RegisterID* FunctionCallResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (RefPtr<RegisterID> local = generator.registerFor(m_ident)) {
-        RefPtr<RegisterID> thisRegister = generator.emitLoad(generator.newTemporary(), jsNull());
-        return generator.emitCall(generator.finalDestination(dst, thisRegister.get()), local.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+    ExpectedFunction expectedFunction = generator.expectedFunctionForIdentifier(m_ident);
+
+    Variable var = generator.variable(m_ident);
+    if (RegisterID* local = var.local()) {
+        RefPtr<RegisterID> func = generator.emitMove(generator.tempDestination(dst), local);
+        RefPtr<RegisterID> returnValue = generator.finalDestination(dst, func.get());
+        CallArguments callArguments(generator, m_args);
+        generator.emitLoad(callArguments.thisRegister(), jsUndefined());
+        // This passes NoExpectedFunction because we expect that if the function is in a
+        // local variable, then it's not one of our built-in constructors.
+        RegisterID* ret = generator.emitCall(returnValue.get(), func.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+        if (generator.vm()->typeProfiler()) {
+            generator.emitProfileType(returnValue.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+            generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+        }
+        return ret;
     }
 
-    int index = 0;
-    size_t depth = 0;
-    JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, false, globalObject) && index != missingSymbolMarker()) {
-        RefPtr<RegisterID> func = generator.emitGetScopedVar(generator.newTemporary(), depth, index, globalObject);
-        RefPtr<RegisterID> thisRegister = generator.emitLoad(generator.newTemporary(), jsNull());
-        return generator.emitCall(generator.finalDestination(dst, func.get()), func.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+    RefPtr<RegisterID> func = generator.newTemporary();
+    RefPtr<RegisterID> returnValue = generator.finalDestination(dst, func.get());
+    CallArguments callArguments(generator, m_args);
+
+    JSTextPosition newDivot = divotStart() + m_ident.length();
+    generator.emitExpressionInfo(newDivot, divotStart(), newDivot);
+    generator.moveToDestinationIfNeeded(
+        callArguments.thisRegister(),
+        generator.emitResolveScope(callArguments.thisRegister(), var));
+    generator.emitGetFromScope(func.get(), callArguments.thisRegister(), var, ThrowIfNotFound);
+    RegisterID* ret = generator.emitCall(returnValue.get(), func.get(), expectedFunction, callArguments, divot(), divotStart(), divotEnd());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(returnValue.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
     }
+    return ret;
+}
 
-    RefPtr<RegisterID> func = generator.newTemporary();
-    RefPtr<RegisterID> thisRegister = generator.newTemporary();
-    int identifierStart = divot() - startOffset();
-    generator.emitExpressionInfo(identifierStart + m_ident.size(), m_ident.size(), 0);
-    generator.emitResolveWithBase(thisRegister.get(), func.get(), m_ident);
-    return generator.emitCall(generator.finalDestination(dst, func.get()), func.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+// ------------------------------ BytecodeIntrinsicNode ----------------------------------
+
+RegisterID* BytecodeIntrinsicNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    return (this->*m_emitter)(generator, dst);
+}
+
+RegisterID* BytecodeIntrinsicNode::emit_intrinsic_putByValDirect(BytecodeGenerator& generator, RegisterID* dst)
+{
+    ArgumentListNode* node = m_args->m_listNode;
+    RefPtr<RegisterID> base = generator.emitNode(node);
+    node = node->m_next;
+    RefPtr<RegisterID> index = generator.emitNode(node);
+    node = node->m_next;
+    RefPtr<RegisterID> value = generator.emitNode(node);
+
+    ASSERT(!node->m_next);
+
+    return generator.moveToDestinationIfNeeded(dst, generator.emitDirectPutByVal(base.get(), index.get(), value.get()));
+}
+
+RegisterID* BytecodeIntrinsicNode::emit_intrinsic_toString(BytecodeGenerator& generator, RegisterID* dst)
+{
+    ArgumentListNode* node = m_args->m_listNode;
+    RefPtr<RegisterID> src = generator.emitNode(node);
+    ASSERT(!node->m_next);
+
+    return generator.moveToDestinationIfNeeded(dst, generator.emitToString(generator.tempDestination(dst), src.get()));
 }
 
 // ------------------------------ FunctionCallBracketNode ----------------------------------
 
 RegisterID* FunctionCallBracketNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> base = generator.emitNode(m_base);
-    RegisterID* property = generator.emitNode(m_subscript);
-    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
-    RefPtr<RegisterID> function = generator.emitGetByVal(generator.tempDestination(dst), base.get(), property);
-    RefPtr<RegisterID> thisRegister = generator.emitMove(generator.newTemporary(), base.get());
-    return generator.emitCall(generator.finalDestination(dst, function.get()), function.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+    bool baseIsSuper = m_base->isSuperNode();
+    bool subscriptIsString = m_subscript->isString();
+
+    RefPtr<RegisterID> base;
+    if (baseIsSuper)
+        base = emitSuperBaseForCallee(generator);
+    else {
+        if (subscriptIsString)
+            base = generator.emitNode(m_base);
+        else
+            base = generator.emitNodeForLeftHandSide(m_base, m_subscriptHasAssignments, m_subscript->isPure(generator));
+    }
+
+    RefPtr<RegisterID> function;
+    if (subscriptIsString) {
+        generator.emitExpressionInfo(subexpressionDivot(), subexpressionStart(), subexpressionEnd());
+        function = generator.emitGetById(generator.tempDestination(dst), base.get(), static_cast<StringNode*>(m_subscript)->value());
+    } else {
+        RefPtr<RegisterID> property = generator.emitNode(m_subscript);
+        generator.emitExpressionInfo(subexpressionDivot(), subexpressionStart(), subexpressionEnd());
+        function = generator.emitGetByVal(generator.tempDestination(dst), base.get(), property.get());
+    }
+
+    RefPtr<RegisterID> returnValue = generator.finalDestination(dst, function.get());
+    CallArguments callArguments(generator, m_args);
+    if (baseIsSuper)
+        generator.emitMove(callArguments.thisRegister(), generator.thisRegister());
+    else
+        generator.emitMove(callArguments.thisRegister(), base.get());
+    RegisterID* ret = generator.emitCall(returnValue.get(), function.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(returnValue.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return ret;
 }
 
 // ------------------------------ FunctionCallDotNode ----------------------------------
@@ -382,12 +845,21 @@ RegisterID* FunctionCallBracketNode::emitBytecode(BytecodeGenerator& generator,
 RegisterID* FunctionCallDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     RefPtr<RegisterID> function = generator.tempDestination(dst);
-    RefPtr<RegisterID> thisRegister = generator.newTemporary();
-    generator.emitNode(thisRegister.get(), m_base);
-    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
-    generator.emitMethodCheck();
-    generator.emitGetById(function.get(), thisRegister.get(), m_ident);
-    return generator.emitCall(generator.finalDestination(dst, function.get()), function.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+    RefPtr<RegisterID> returnValue = generator.finalDestination(dst, function.get());
+    CallArguments callArguments(generator, m_args);
+    bool baseIsSuper = m_base->isSuperNode();
+    if (baseIsSuper)
+        generator.emitMove(callArguments.thisRegister(), generator.thisRegister());
+    else
+        generator.emitNode(callArguments.thisRegister(), m_base);
+    generator.emitExpressionInfo(subexpressionDivot(), subexpressionStart(), subexpressionEnd());
+    generator.emitGetById(function.get(), baseIsSuper ? emitSuperBaseForCallee(generator) : callArguments.thisRegister(), m_ident);
+    RegisterID* ret = generator.emitCall(returnValue.get(), function.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(returnValue.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return ret;
 }
 
 RegisterID* CallFunctionCallDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
@@ -395,33 +867,59 @@ RegisterID* CallFunctionCallDotNode::emitBytecode(BytecodeGenerator& generator,
     RefPtr<Label> realCall = generator.newLabel();
     RefPtr<Label> end = generator.newLabel();
     RefPtr<RegisterID> base = generator.emitNode(m_base);
-    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
-    RefPtr<RegisterID> function = generator.emitGetById(generator.tempDestination(dst), base.get(), m_ident);
-    RefPtr<RegisterID> finalDestination = generator.finalDestination(dst, function.get());
-    generator.emitJumpIfNotFunctionCall(function.get(), realCall.get());
+    generator.emitExpressionInfo(subexpressionDivot(), subexpressionStart(), subexpressionEnd());
+    RefPtr<RegisterID> function;
+    bool emitCallCheck = !generator.isBuiltinFunction();
+    if (emitCallCheck) {
+        function = generator.emitGetById(generator.tempDestination(dst), base.get(), generator.propertyNames().builtinNames().callPublicName());
+        generator.emitJumpIfNotFunctionCall(function.get(), realCall.get());
+    }
+    RefPtr<RegisterID> returnValue = generator.finalDestination(dst);
     {
-        RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
-        RefPtr<RegisterID> thisRegister = generator.newTemporary();
-        ArgumentListNode* oldList = m_args->m_listNode;
-        if (m_args->m_listNode && m_args->m_listNode->m_expr) {
-            generator.emitNode(thisRegister.get(), m_args->m_listNode->m_expr);
+        if (m_args->m_listNode && m_args->m_listNode->m_expr && m_args->m_listNode->m_expr->isSpreadExpression()) {
+            RefPtr<RegisterID> profileHookRegister;
+            if (generator.shouldEmitProfileHooks())
+                profileHookRegister = generator.newTemporary();
+            SpreadExpressionNode* spread = static_cast<SpreadExpressionNode*>(m_args->m_listNode->m_expr);
+            ExpressionNode* subject = spread->expression();
+            RefPtr<RegisterID> argumentsRegister;
+            argumentsRegister = generator.emitNode(subject);
+            generator.emitExpressionInfo(spread->divot(), spread->divotStart(), spread->divotEnd());
+            RefPtr<RegisterID> thisRegister = generator.emitGetByVal(generator.newTemporary(), argumentsRegister.get(), generator.emitLoad(0, jsNumber(0)));
+            generator.emitCallVarargs(returnValue.get(), base.get(), thisRegister.get(), argumentsRegister.get(), generator.newTemporary(), 1, profileHookRegister.get(), divot(), divotStart(), divotEnd());
+        } else if (m_args->m_listNode && m_args->m_listNode->m_expr) {
+            ArgumentListNode* oldList = m_args->m_listNode;
             m_args->m_listNode = m_args->m_listNode->m_next;
-        } else
-            generator.emitLoad(thisRegister.get(), jsNull());
 
-        generator.emitCall(finalDestination.get(), realFunction.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+            RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
+            CallArguments callArguments(generator, m_args);
+            generator.emitNode(callArguments.thisRegister(), oldList->m_expr);
+            generator.emitCall(returnValue.get(), realFunction.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+            m_args->m_listNode = oldList;
+        } else {
+            RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
+            CallArguments callArguments(generator, m_args);
+            generator.emitLoad(callArguments.thisRegister(), jsUndefined());
+            generator.emitCall(returnValue.get(), realFunction.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+        }
+    }
+    if (emitCallCheck) {
         generator.emitJump(end.get());
-        m_args->m_listNode = oldList;
+        generator.emitLabel(realCall.get());
+        {
+            CallArguments callArguments(generator, m_args);
+            generator.emitMove(callArguments.thisRegister(), base.get());
+            generator.emitCall(returnValue.get(), function.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+        }
+        generator.emitLabel(end.get());
     }
-    generator.emitLabel(realCall.get());
-    {
-        RefPtr<RegisterID> thisRegister = generator.emitMove(generator.newTemporary(), base.get());
-        generator.emitCall(finalDestination.get(), function.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(returnValue.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
     }
-    generator.emitLabel(end.get());
-    return finalDestination.get();
+    return returnValue.get();
 }
-    
+
 static bool areTrivialApplyArguments(ArgumentsNode* args)
 {
     return !args->m_listNode || !args->m_listNode->m_expr || !args->m_listNode->m_next
@@ -438,185 +936,236 @@ RegisterID* ApplyFunctionCallDotNode::emitBytecode(BytecodeGenerator& generator,
     RefPtr<Label> realCall = generator.newLabel();
     RefPtr<Label> end = generator.newLabel();
     RefPtr<RegisterID> base = generator.emitNode(m_base);
-    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
-    RefPtr<RegisterID> function = generator.emitGetById(generator.tempDestination(dst), base.get(), m_ident);
-    RefPtr<RegisterID> finalDestination = generator.finalDestination(dst, function.get());
-    generator.emitJumpIfNotFunctionApply(function.get(), realCall.get());
-    {
-        if (mayBeCall) {
-            RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
-            RefPtr<RegisterID> thisRegister = generator.newTemporary();
+    generator.emitExpressionInfo(subexpressionDivot(), subexpressionStart(), subexpressionEnd());
+    RefPtr<RegisterID> function;
+    RefPtr<RegisterID> returnValue = generator.finalDestination(dst, function.get());
+    bool emitCallCheck = !generator.isBuiltinFunction();
+    if (emitCallCheck) {
+        function = generator.emitGetById(generator.tempDestination(dst), base.get(), generator.propertyNames().builtinNames().applyPublicName());
+        generator.emitJumpIfNotFunctionApply(function.get(), realCall.get());
+    }
+    if (mayBeCall) {
+        if (m_args->m_listNode && m_args->m_listNode->m_expr) {
             ArgumentListNode* oldList = m_args->m_listNode;
-            if (m_args->m_listNode && m_args->m_listNode->m_expr) {
-                generator.emitNode(thisRegister.get(), m_args->m_listNode->m_expr);
+            if (m_args->m_listNode->m_expr->isSpreadExpression()) {
+                SpreadExpressionNode* spread = static_cast<SpreadExpressionNode*>(m_args->m_listNode->m_expr);
+                RefPtr<RegisterID> profileHookRegister;
+                if (generator.shouldEmitProfileHooks())
+                    profileHookRegister = generator.newTemporary();
+                RefPtr<RegisterID> realFunction = generator.emitMove(generator.newTemporary(), base.get());
+                RefPtr<RegisterID> index = generator.emitLoad(generator.newTemporary(), jsNumber(0));
+                RefPtr<RegisterID> thisRegister = generator.emitLoad(generator.newTemporary(), jsUndefined());
+                RefPtr<RegisterID> argumentsRegister = generator.emitLoad(generator.newTemporary(), jsUndefined());
+                
+                auto extractor = [&thisRegister, &argumentsRegister, &index](BytecodeGenerator& generator, RegisterID* value)
+                {
+                    RefPtr<Label> haveThis = generator.newLabel();
+                    RefPtr<Label> end = generator.newLabel();
+                    RefPtr<RegisterID> compareResult = generator.newTemporary();
+                    RefPtr<RegisterID> indexZeroCompareResult = generator.emitBinaryOp(op_eq, compareResult.get(), index.get(), generator.emitLoad(0, jsNumber(0)), OperandTypes(ResultType::numberTypeIsInt32(), ResultType::numberTypeIsInt32()));
+                    generator.emitJumpIfFalse(indexZeroCompareResult.get(), haveThis.get());
+                    generator.emitMove(thisRegister.get(), value);
+                    generator.emitLoad(index.get(), jsNumber(1));
+                    generator.emitJump(end.get());
+                    generator.emitLabel(haveThis.get());
+                    RefPtr<RegisterID> indexOneCompareResult = generator.emitBinaryOp(op_eq, compareResult.get(), index.get(), generator.emitLoad(0, jsNumber(1)), OperandTypes(ResultType::numberTypeIsInt32(), ResultType::numberTypeIsInt32()));
+                    generator.emitJumpIfFalse(indexOneCompareResult.get(), end.get());
+                    generator.emitMove(argumentsRegister.get(), value);
+                    generator.emitLoad(index.get(), jsNumber(2));
+                    generator.emitLabel(end.get());
+                };
+                generator.emitEnumeration(this, spread->expression(), extractor);
+                generator.emitCallVarargs(returnValue.get(), realFunction.get(), thisRegister.get(), argumentsRegister.get(), generator.newTemporary(), 0, profileHookRegister.get(), divot(), divotStart(), divotEnd());
+            } else if (m_args->m_listNode->m_next) {
+                ASSERT(m_args->m_listNode->m_next->m_expr->isSimpleArray());
+                ASSERT(!m_args->m_listNode->m_next->m_next);
+                m_args->m_listNode = static_cast<ArrayNode*>(m_args->m_listNode->m_next->m_expr)->toArgumentList(generator.parserArena(), 0, 0);
+                RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
+                CallArguments callArguments(generator, m_args);
+                generator.emitNode(callArguments.thisRegister(), oldList->m_expr);
+                generator.emitCall(returnValue.get(), realFunction.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+            } else {
                 m_args->m_listNode = m_args->m_listNode->m_next;
-                if (m_args->m_listNode) {
-                    ASSERT(m_args->m_listNode->m_expr->isSimpleArray());
-                    ASSERT(!m_args->m_listNode->m_next);
-                    m_args->m_listNode = static_cast<ArrayNode*>(m_args->m_listNode->m_expr)->toArgumentList(generator.globalData());
-                }
-            } else
-                generator.emitLoad(thisRegister.get(), jsNull());
-            generator.emitCall(finalDestination.get(), realFunction.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+                RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
+                CallArguments callArguments(generator, m_args);
+                generator.emitNode(callArguments.thisRegister(), oldList->m_expr);
+                generator.emitCall(returnValue.get(), realFunction.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+            }
             m_args->m_listNode = oldList;
         } else {
-            ASSERT(m_args->m_listNode && m_args->m_listNode->m_next);
-            RefPtr<RegisterID> realFunction = generator.emitMove(generator.newTemporary(), base.get());
-            RefPtr<RegisterID> argsCountRegister = generator.newTemporary();
-            RefPtr<RegisterID> thisRegister = generator.newTemporary();
-            RefPtr<RegisterID> argsRegister = generator.newTemporary();
-            generator.emitNode(thisRegister.get(), m_args->m_listNode->m_expr);
-            ArgumentListNode* args = m_args->m_listNode->m_next;
-            bool isArgumentsApply = false;
-            if (args->m_expr->isResolveNode()) {
-                ResolveNode* resolveNode = static_cast<ResolveNode*>(args->m_expr);
-                isArgumentsApply = generator.willResolveToArguments(resolveNode->identifier());
-                if (isArgumentsApply)
-                    generator.emitMove(argsRegister.get(), generator.uncheckedRegisterForArguments());
-            }
-            if (!isArgumentsApply)
-                generator.emitNode(argsRegister.get(), args->m_expr);
-            while ((args = args->m_next))
-                generator.emitNode(args->m_expr);
-
-            generator.emitLoadVarargs(argsCountRegister.get(), argsRegister.get());
-            generator.emitCallVarargs(finalDestination.get(), realFunction.get(), thisRegister.get(), argsCountRegister.get(), divot(), startOffset(), endOffset());
+            RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
+            CallArguments callArguments(generator, m_args);
+            generator.emitLoad(callArguments.thisRegister(), jsUndefined());
+            generator.emitCall(returnValue.get(), realFunction.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
         }
+    } else {
+        ASSERT(m_args->m_listNode && m_args->m_listNode->m_next);
+        RefPtr<RegisterID> profileHookRegister;
+        if (generator.shouldEmitProfileHooks())
+            profileHookRegister = generator.newTemporary();
+        RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
+        RefPtr<RegisterID> thisRegister = generator.emitNode(m_args->m_listNode->m_expr);
+        RefPtr<RegisterID> argsRegister;
+        ArgumentListNode* args = m_args->m_listNode->m_next;
+        argsRegister = generator.emitNode(args->m_expr);
+
+        // Function.prototype.apply ignores extra arguments, but we still
+        // need to evaluate them for side effects.
+        while ((args = args->m_next))
+            generator.emitNode(args->m_expr);
+
+        generator.emitCallVarargs(returnValue.get(), realFunction.get(), thisRegister.get(), argsRegister.get(), generator.newTemporary(), 0, profileHookRegister.get(), divot(), divotStart(), divotEnd());
+    }
+    if (emitCallCheck) {
         generator.emitJump(end.get());
+        generator.emitLabel(realCall.get());
+        CallArguments callArguments(generator, m_args);
+        generator.emitMove(callArguments.thisRegister(), base.get());
+        generator.emitCall(returnValue.get(), function.get(), NoExpectedFunction, callArguments, divot(), divotStart(), divotEnd());
+        generator.emitLabel(end.get());
     }
-    generator.emitLabel(realCall.get());
-    {
-        RefPtr<RegisterID> thisRegister = generator.emitMove(generator.newTemporary(), base.get());
-        generator.emitCall(finalDestination.get(), function.get(), thisRegister.get(), m_args, divot(), startOffset(), endOffset());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(returnValue.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
     }
-    generator.emitLabel(end.get());
-    return finalDestination.get();
+    return returnValue.get();
 }
 
-// ------------------------------ PostfixResolveNode ----------------------------------
+// ------------------------------ PostfixNode ----------------------------------
 
-static RegisterID* emitPreIncOrDec(BytecodeGenerator& generator, RegisterID* srcDst, Operator oper)
+static RegisterID* emitIncOrDec(BytecodeGenerator& generator, RegisterID* srcDst, Operator oper)
 {
-    return (oper == OpPlusPlus) ? generator.emitPreInc(srcDst) : generator.emitPreDec(srcDst);
+    return (oper == OpPlusPlus) ? generator.emitInc(srcDst) : generator.emitDec(srcDst);
 }
 
 static RegisterID* emitPostIncOrDec(BytecodeGenerator& generator, RegisterID* dst, RegisterID* srcDst, Operator oper)
 {
-    if (srcDst == dst)
-        return generator.emitToJSNumber(dst, srcDst);
-    return (oper == OpPlusPlus) ? generator.emitPostInc(dst, srcDst) : generator.emitPostDec(dst, srcDst);
+    if (dst == srcDst)
+        return generator.emitToNumber(generator.finalDestination(dst), srcDst);
+    RefPtr<RegisterID> tmp = generator.emitToNumber(generator.tempDestination(dst), srcDst);
+    emitIncOrDec(generator, srcDst, oper);
+    return generator.moveToDestinationIfNeeded(dst, tmp.get());
 }
 
-RegisterID* PostfixResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* PostfixNode::emitResolve(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (RegisterID* local = generator.registerFor(m_ident)) {
-        if (generator.isLocalConstant(m_ident)) {
-            if (dst == generator.ignoredResult())
-                return 0;
-            return generator.emitToJSNumber(generator.finalDestination(dst), local);
-        }
-
-        if (dst == generator.ignoredResult())
-            return emitPreIncOrDec(generator, local, m_operator);
-        return emitPostIncOrDec(generator, generator.finalDestination(dst), local, m_operator);
-    }
-
-    int index = 0;
-    size_t depth = 0;
-    JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, true, globalObject) && index != missingSymbolMarker()) {
-        RefPtr<RegisterID> value = generator.emitGetScopedVar(generator.newTemporary(), depth, index, globalObject);
-        RegisterID* oldValue;
-        if (dst == generator.ignoredResult()) {
-            oldValue = 0;
-            emitPreIncOrDec(generator, value.get(), m_operator);
-        } else {
-            oldValue = emitPostIncOrDec(generator, generator.finalDestination(dst), value.get(), m_operator);
+    if (dst == generator.ignoredResult())
+        return PrefixNode::emitResolve(generator, dst);
+
+    ASSERT(m_expr->isResolveNode());
+    ResolveNode* resolve = static_cast<ResolveNode*>(m_expr);
+    const Identifier& ident = resolve->identifier();
+
+    Variable var = generator.variable(ident);
+    if (RegisterID* local = var.local()) {
+        RefPtr<RegisterID> localReg = local;
+        if (var.isReadOnly()) {
+            generator.emitReadOnlyExceptionIfNeeded();
+            localReg = generator.emitMove(generator.tempDestination(dst), local);
+        } else if (generator.vm()->typeProfiler()) {
+            RefPtr<RegisterID> tempDst = generator.finalDestination(dst);
+            ASSERT(dst != localReg);
+            RefPtr<RegisterID> tempDstSrc = generator.newTemporary();
+            generator.emitToNumber(tempDst.get(), localReg.get());
+            generator.emitMove(tempDstSrc.get(), localReg.get());
+            emitIncOrDec(generator, tempDstSrc.get(), m_operator);
+            generator.emitMove(localReg.get(), tempDstSrc.get());
+            if (generator.vm()->typeProfiler())
+                generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+            return tempDst.get();
         }
-        generator.emitPutScopedVar(depth, index, value.get(), globalObject);
-        return oldValue;
+        return emitPostIncOrDec(generator, generator.finalDestination(dst), localReg.get(), m_operator);
     }
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    RefPtr<RegisterID> value = generator.newTemporary();
-    RefPtr<RegisterID> base = generator.emitResolveWithBase(generator.newTemporary(), value.get(), m_ident);
-    RegisterID* oldValue;
-    if (dst == generator.ignoredResult()) {
-        oldValue = 0;
-        emitPreIncOrDec(generator, value.get(), m_operator);
-    } else {
-        oldValue = emitPostIncOrDec(generator, generator.finalDestination(dst), value.get(), m_operator);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RefPtr<RegisterID> scope = generator.emitResolveScope(nullptr, var);
+    RefPtr<RegisterID> value = generator.emitGetFromScope(generator.newTemporary(), scope.get(), var, ThrowIfNotFound);
+    RefPtr<RegisterID> oldValue = emitPostIncOrDec(generator, generator.finalDestination(dst), value.get(), m_operator);
+    generator.emitPutToScope(scope.get(), var, value.get(), ThrowIfNotFound);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(value.get(), var.isResolved() ? ProfileTypeBytecodePutToLocalScope : ProfileTypeBytecodePutToScope, &ident);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
     }
-    generator.emitPutById(base.get(), m_ident, value.get());
-    return oldValue;
-}
 
-// ------------------------------ PostfixBracketNode ----------------------------------
+    return oldValue.get();
+}
 
-RegisterID* PostfixBracketNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* PostfixNode::emitBracket(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> base = generator.emitNode(m_base);
-    RefPtr<RegisterID> property = generator.emitNode(m_subscript);
+    if (dst == generator.ignoredResult())
+        return PrefixNode::emitBracket(generator, dst);
+
+    ASSERT(m_expr->isBracketAccessorNode());
+    BracketAccessorNode* bracketAccessor = static_cast<BracketAccessorNode*>(m_expr);
+    ExpressionNode* baseNode = bracketAccessor->base();
+    ExpressionNode* subscript = bracketAccessor->subscript();
 
-    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
+    RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(baseNode, bracketAccessor->subscriptHasAssignments(), subscript->isPure(generator));
+    RefPtr<RegisterID> property = generator.emitNode(subscript);
+
+    generator.emitExpressionInfo(bracketAccessor->divot(), bracketAccessor->divotStart(), bracketAccessor->divotEnd());
     RefPtr<RegisterID> value = generator.emitGetByVal(generator.newTemporary(), base.get(), property.get());
-    RegisterID* oldValue;
-    if (dst == generator.ignoredResult()) {
-        oldValue = 0;
-        if (m_operator == OpPlusPlus)
-            generator.emitPreInc(value.get());
-        else
-            generator.emitPreDec(value.get());
-    } else {
-        oldValue = (m_operator == OpPlusPlus) ? generator.emitPostInc(generator.finalDestination(dst), value.get()) : generator.emitPostDec(generator.finalDestination(dst), value.get());
-    }
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
+    RegisterID* oldValue = emitPostIncOrDec(generator, generator.tempDestination(dst), value.get(), m_operator);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
     generator.emitPutByVal(base.get(), property.get(), value.get());
-    return oldValue;
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(value.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return generator.moveToDestinationIfNeeded(dst, oldValue);
 }
 
-// ------------------------------ PostfixDotNode ----------------------------------
-
-RegisterID* PostfixDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* PostfixNode::emitDot(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> base = generator.emitNode(m_base);
-
-    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
-    RefPtr<RegisterID> value = generator.emitGetById(generator.newTemporary(), base.get(), m_ident);
-    RegisterID* oldValue;
-    if (dst == generator.ignoredResult()) {
-        oldValue = 0;
-        if (m_operator == OpPlusPlus)
-            generator.emitPreInc(value.get());
-        else
-            generator.emitPreDec(value.get());
-    } else {
-        oldValue = (m_operator == OpPlusPlus) ? generator.emitPostInc(generator.finalDestination(dst), value.get()) : generator.emitPostDec(generator.finalDestination(dst), value.get());
+    if (dst == generator.ignoredResult())
+        return PrefixNode::emitDot(generator, dst);
+
+    ASSERT(m_expr->isDotAccessorNode());
+    DotAccessorNode* dotAccessor = static_cast<DotAccessorNode*>(m_expr);
+    ExpressionNode* baseNode = dotAccessor->base();
+    const Identifier& ident = dotAccessor->identifier();
+
+    RefPtr<RegisterID> base = generator.emitNode(baseNode);
+
+    generator.emitExpressionInfo(dotAccessor->divot(), dotAccessor->divotStart(), dotAccessor->divotEnd());
+    RefPtr<RegisterID> value = generator.emitGetById(generator.newTemporary(), base.get(), ident);
+    RegisterID* oldValue = emitPostIncOrDec(generator, generator.tempDestination(dst), value.get(), m_operator);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    generator.emitPutById(base.get(), ident, value.get());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(value.get(), ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
     }
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    generator.emitPutById(base.get(), m_ident, value.get());
-    return oldValue;
+    return generator.moveToDestinationIfNeeded(dst, oldValue);
 }
 
-// ------------------------------ PostfixErrorNode -----------------------------------
-
-RegisterID* PostfixErrorNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+RegisterID* PostfixNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    return emitThrowError(generator, ReferenceError, m_operator == OpPlusPlus
-        ? "Postfix ++ operator applied to value that is not a reference."
-        : "Postfix -- operator applied to value that is not a reference.");
+    if (m_expr->isResolveNode())
+        return emitResolve(generator, dst);
+
+    if (m_expr->isBracketAccessorNode())
+        return emitBracket(generator, dst);
+
+    if (m_expr->isDotAccessorNode())
+        return emitDot(generator, dst);
+
+    return emitThrowReferenceError(generator, m_operator == OpPlusPlus
+        ? ASCIILiteral("Postfix ++ operator applied to value that is not a reference.")
+        : ASCIILiteral("Postfix -- operator applied to value that is not a reference."));
 }
 
 // ------------------------------ DeleteResolveNode -----------------------------------
 
 RegisterID* DeleteResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (generator.registerFor(m_ident))
+    Variable var = generator.variable(m_ident);
+    if (var.local())
         return generator.emitLoad(generator.finalDestination(dst), false);
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    RegisterID* base = generator.emitResolveBase(generator.tempDestination(dst), m_ident);
-    return generator.emitDeleteById(generator.finalDestination(dst, base), base, m_ident);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RefPtr<RegisterID> base = generator.emitResolveScope(dst, var);
+    return generator.emitDeleteById(generator.finalDestination(dst, base.get()), base.get(), m_ident);
 }
 
 // ------------------------------ DeleteBracketNode -----------------------------------
@@ -624,20 +1173,24 @@ RegisterID* DeleteResolveNode::emitBytecode(BytecodeGenerator& generator, Regist
 RegisterID* DeleteBracketNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     RefPtr<RegisterID> r0 = generator.emitNode(m_base);
-    RegisterID* r1 = generator.emitNode(m_subscript);
+    RefPtr<RegisterID> r1 = generator.emitNode(m_subscript);
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    return generator.emitDeleteByVal(generator.finalDestination(dst), r0.get(), r1);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    if (m_base->isSuperNode())
+        return emitThrowReferenceError(generator, "Cannot delete a super property");
+    return generator.emitDeleteByVal(generator.finalDestination(dst), r0.get(), r1.get());
 }
 
 // ------------------------------ DeleteDotNode -----------------------------------
 
 RegisterID* DeleteDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RegisterID* r0 = generator.emitNode(m_base);
+    RefPtr<RegisterID> r0 = generator.emitNode(m_base);
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    return generator.emitDeleteById(generator.finalDestination(dst), r0, m_ident);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    if (m_base->isSuperNode())
+        return emitThrowReferenceError(generator, "Cannot delete a super property");
+    return generator.emitDeleteById(generator.finalDestination(dst), r0.get(), m_ident);
 }
 
 // ------------------------------ DeleteValueNode -----------------------------------
@@ -662,21 +1215,22 @@ RegisterID* VoidNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst
     return generator.emitLoad(dst, jsUndefined());
 }
 
-// ------------------------------ TypeOfValueNode -----------------------------------
+// ------------------------------ TypeOfResolveNode -----------------------------------
 
 RegisterID* TypeOfResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (RegisterID* local = generator.registerFor(m_ident)) {
+    Variable var = generator.variable(m_ident);
+    if (RegisterID* local = var.local()) {
         if (dst == generator.ignoredResult())
             return 0;
         return generator.emitTypeOf(generator.finalDestination(dst), local);
     }
 
-    RefPtr<RegisterID> scratch = generator.emitResolveBase(generator.tempDestination(dst), m_ident);
-    generator.emitGetById(scratch.get(), scratch.get(), m_ident);
+    RefPtr<RegisterID> scope = generator.emitResolveScope(dst, var);
+    RefPtr<RegisterID> value = generator.emitGetFromScope(generator.newTemporary(), scope.get(), var, DoNotThrowIfNotFound);
     if (dst == generator.ignoredResult())
         return 0;
-    return generator.emitTypeOf(generator.finalDestination(dst, scratch.get()), scratch.get());
+    return generator.emitTypeOf(generator.finalDestination(dst, scope.get()), value.get());
 }
 
 // ------------------------------ TypeOfValueNode -----------------------------------
@@ -691,103 +1245,130 @@ RegisterID* TypeOfValueNode::emitBytecode(BytecodeGenerator& generator, Register
     return generator.emitTypeOf(generator.finalDestination(dst), src.get());
 }
 
-// ------------------------------ PrefixResolveNode ----------------------------------
-
-RegisterID* PrefixResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
-{
-    if (RegisterID* local = generator.registerFor(m_ident)) {
-        if (generator.isLocalConstant(m_ident)) {
-            if (dst == generator.ignoredResult())
-                return 0;
-            RefPtr<RegisterID> r0 = generator.emitLoad(generator.finalDestination(dst), (m_operator == OpPlusPlus) ? 1.0 : -1.0);
-            return generator.emitBinaryOp(op_add, r0.get(), local, r0.get(), OperandTypes());
+// ------------------------------ PrefixNode ----------------------------------
+
+RegisterID* PrefixNode::emitResolve(BytecodeGenerator& generator, RegisterID* dst)
+{
+    ASSERT(m_expr->isResolveNode());
+    ResolveNode* resolve = static_cast<ResolveNode*>(m_expr);
+    const Identifier& ident = resolve->identifier();
+
+    Variable var = generator.variable(ident);
+    if (RegisterID* local = var.local()) {
+        RefPtr<RegisterID> localReg = local;
+        if (var.isReadOnly()) {
+            generator.emitReadOnlyExceptionIfNeeded();
+            localReg = generator.emitMove(generator.tempDestination(dst), localReg.get());
+        } else if (generator.vm()->typeProfiler()) {
+            RefPtr<RegisterID> tempDst = generator.tempDestination(dst);
+            generator.emitMove(tempDst.get(), localReg.get());
+            emitIncOrDec(generator, tempDst.get(), m_operator);
+            generator.emitMove(localReg.get(), tempDst.get());
+            if (generator.vm()->typeProfiler())
+                generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+            return generator.moveToDestinationIfNeeded(dst, tempDst.get());
         }
-
-        emitPreIncOrDec(generator, local, m_operator);
-        return generator.moveToDestinationIfNeeded(dst, local);
+        emitIncOrDec(generator, localReg.get(), m_operator);
+        return generator.moveToDestinationIfNeeded(dst, localReg.get());
     }
 
-    int index = 0;
-    size_t depth = 0;
-    JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, false, globalObject) && index != missingSymbolMarker()) {
-        RefPtr<RegisterID> propDst = generator.emitGetScopedVar(generator.tempDestination(dst), depth, index, globalObject);
-        emitPreIncOrDec(generator, propDst.get(), m_operator);
-        generator.emitPutScopedVar(depth, index, propDst.get(), globalObject);
-        return generator.moveToDestinationIfNeeded(dst, propDst.get());
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RefPtr<RegisterID> scope = generator.emitResolveScope(dst, var);
+    RefPtr<RegisterID> value = generator.emitGetFromScope(generator.newTemporary(), scope.get(), var, ThrowIfNotFound);
+    emitIncOrDec(generator, value.get(), m_operator);
+    generator.emitPutToScope(scope.get(), var, value.get(), ThrowIfNotFound);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(value.get(), var.isResolved() ? ProfileTypeBytecodePutToLocalScope : ProfileTypeBytecodePutToScope, &ident);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
     }
-
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    RefPtr<RegisterID> propDst = generator.tempDestination(dst);
-    RefPtr<RegisterID> base = generator.emitResolveWithBase(generator.newTemporary(), propDst.get(), m_ident);
-    emitPreIncOrDec(generator, propDst.get(), m_operator);
-    generator.emitPutById(base.get(), m_ident, propDst.get());
-    return generator.moveToDestinationIfNeeded(dst, propDst.get());
+    return generator.moveToDestinationIfNeeded(dst, value.get());
 }
 
-// ------------------------------ PrefixBracketNode ----------------------------------
-
-RegisterID* PrefixBracketNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* PrefixNode::emitBracket(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> base = generator.emitNode(m_base);
-    RefPtr<RegisterID> property = generator.emitNode(m_subscript);
+    ASSERT(m_expr->isBracketAccessorNode());
+    BracketAccessorNode* bracketAccessor = static_cast<BracketAccessorNode*>(m_expr);
+    ExpressionNode* baseNode = bracketAccessor->base();
+    ExpressionNode* subscript = bracketAccessor->subscript();
+
+    RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(baseNode, bracketAccessor->subscriptHasAssignments(), subscript->isPure(generator));
+    RefPtr<RegisterID> property = generator.emitNode(subscript);
     RefPtr<RegisterID> propDst = generator.tempDestination(dst);
 
-    generator.emitExpressionInfo(divot() + m_subexpressionDivotOffset, m_subexpressionStartOffset, endOffset() - m_subexpressionDivotOffset);
+    generator.emitExpressionInfo(bracketAccessor->divot(), bracketAccessor->divotStart(), bracketAccessor->divotEnd());
     RegisterID* value = generator.emitGetByVal(propDst.get(), base.get(), property.get());
-    if (m_operator == OpPlusPlus)
-        generator.emitPreInc(value);
-    else
-        generator.emitPreDec(value);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
+    emitIncOrDec(generator, value, m_operator);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
     generator.emitPutByVal(base.get(), property.get(), value);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(value, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
     return generator.moveToDestinationIfNeeded(dst, propDst.get());
 }
 
-// ------------------------------ PrefixDotNode ----------------------------------
-
-RegisterID* PrefixDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* PrefixNode::emitDot(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> base = generator.emitNode(m_base);
+    ASSERT(m_expr->isDotAccessorNode());
+    DotAccessorNode* dotAccessor = static_cast<DotAccessorNode*>(m_expr);
+    ExpressionNode* baseNode = dotAccessor->base();
+    const Identifier& ident = dotAccessor->identifier();
+
+    RefPtr<RegisterID> base = generator.emitNode(baseNode);
     RefPtr<RegisterID> propDst = generator.tempDestination(dst);
 
-    generator.emitExpressionInfo(divot() + m_subexpressionDivotOffset, m_subexpressionStartOffset, endOffset() - m_subexpressionDivotOffset);
-    RegisterID* value = generator.emitGetById(propDst.get(), base.get(), m_ident);
-    if (m_operator == OpPlusPlus)
-        generator.emitPreInc(value);
-    else
-        generator.emitPreDec(value);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    generator.emitPutById(base.get(), m_ident, value);
+    generator.emitExpressionInfo(dotAccessor->divot(), dotAccessor->divotStart(), dotAccessor->divotEnd());
+    RegisterID* value = generator.emitGetById(propDst.get(), base.get(), ident);
+    emitIncOrDec(generator, value, m_operator);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    generator.emitPutById(base.get(), ident, value);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(value, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
     return generator.moveToDestinationIfNeeded(dst, propDst.get());
 }
 
-// ------------------------------ PrefixErrorNode -----------------------------------
-
-RegisterID* PrefixErrorNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+RegisterID* PrefixNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    return emitThrowError(generator, ReferenceError, m_operator == OpPlusPlus
-        ? "Prefix ++ operator applied to value that is not a reference."
-        : "Prefix -- operator applied to value that is not a reference.");
+    if (m_expr->isResolveNode())
+        return emitResolve(generator, dst);
+
+    if (m_expr->isBracketAccessorNode())
+        return emitBracket(generator, dst);
+
+    if (m_expr->isDotAccessorNode())
+        return emitDot(generator, dst);
+
+    return emitThrowReferenceError(generator, m_operator == OpPlusPlus
+        ? ASCIILiteral("Prefix ++ operator applied to value that is not a reference.")
+        : ASCIILiteral("Prefix -- operator applied to value that is not a reference."));
 }
 
 // ------------------------------ Unary Operation Nodes -----------------------------------
 
 RegisterID* UnaryOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RegisterID* src = generator.emitNode(m_expr);
-    return generator.emitUnaryOp(opcodeID(), generator.finalDestination(dst), src);
+    RefPtr<RegisterID> src = generator.emitNode(m_expr);
+    generator.emitExpressionInfo(position(), position(), position());
+    return generator.emitUnaryOp(opcodeID(), generator.finalDestination(dst), src.get());
 }
 
-
+// ------------------------------ BitwiseNotNode -----------------------------------
+ 
+RegisterID* BitwiseNotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    RefPtr<RegisterID> src2 = generator.emitLoad(generator.newTemporary(), jsNumber(-1));
+    RefPtr<RegisterID> src1 = generator.emitNode(m_expr);
+    return generator.emitBinaryOp(op_bitxor, generator.finalDestination(dst, src1.get()), src1.get(), src2.get(), OperandTypes(m_expr->resultDescriptor(), ResultType::numberTypeIsInt32()));
+}
+ 
 // ------------------------------ LogicalNotNode -----------------------------------
 
-void LogicalNotNode::emitBytecodeInConditionContext(BytecodeGenerator& generator, Label* trueTarget, Label* falseTarget, bool fallThroughMeansTrue)
+void LogicalNotNode::emitBytecodeInConditionContext(BytecodeGenerator& generator, Label* trueTarget, Label* falseTarget, FallThroughMode fallThroughMode)
 {
-    ASSERT(expr()->hasConditionContextCodegen());
-
     // reverse the true and false targets
-    generator.emitNodeInConditionContext(expr(), falseTarget, trueTarget, !fallThroughMeansTrue);
+    generator.emitNodeInConditionContext(expr(), falseTarget, trueTarget, invert(fallThroughMode));
 }
 
 
@@ -901,8 +1482,7 @@ RegisterID* BinaryOpNode::emitStrcat(BytecodeGenerator& generator, RegisterID* d
     // Certain read-modify nodes require expression info to be emitted *after* m_right has been generated.
     // If this is required the node is passed as 'emitExpressionInfoForMe'; do so now.
     if (emitExpressionInfoForMe)
-        generator.emitExpressionInfo(emitExpressionInfoForMe->divot(), emitExpressionInfoForMe->startOffset(), emitExpressionInfoForMe->endOffset());
-
+        generator.emitExpressionInfo(emitExpressionInfoForMe->divot(), emitExpressionInfoForMe->divotStart(), emitExpressionInfoForMe->divotEnd());
     // If there is an assignment convert the lhs now.  This will also copy lhs to
     // the temporary register we allocated for it.
     if (lhs)
@@ -911,12 +1491,72 @@ RegisterID* BinaryOpNode::emitStrcat(BytecodeGenerator& generator, RegisterID* d
     return generator.emitStrcat(generator.finalDestination(dst, temporaryRegisters[0].get()), temporaryRegisters[0].get(), temporaryRegisters.size());
 }
 
+void BinaryOpNode::emitBytecodeInConditionContext(BytecodeGenerator& generator, Label* trueTarget, Label* falseTarget, FallThroughMode fallThroughMode)
+{
+    TriState branchCondition;
+    ExpressionNode* branchExpression;
+    tryFoldToBranch(generator, branchCondition, branchExpression);
+
+    if (branchCondition == MixedTriState)
+        ExpressionNode::emitBytecodeInConditionContext(generator, trueTarget, falseTarget, fallThroughMode);
+    else if (branchCondition == TrueTriState)
+        generator.emitNodeInConditionContext(branchExpression, trueTarget, falseTarget, fallThroughMode);
+    else
+        generator.emitNodeInConditionContext(branchExpression, falseTarget, trueTarget, invert(fallThroughMode));
+}
+
+static inline bool canFoldToBranch(OpcodeID opcodeID, ExpressionNode* branchExpression, JSValue constant)
+{
+    ResultType expressionType = branchExpression->resultDescriptor();
+
+    if (expressionType.definitelyIsBoolean() && constant.isBoolean())
+        return true;
+    else if (expressionType.definitelyIsBoolean() && constant.isInt32() && (constant.asInt32() == 0 || constant.asInt32() == 1))
+        return opcodeID == op_eq || opcodeID == op_neq; // Strict equality is false in the case of type mismatch.
+    else if (expressionType.isInt32() && constant.isInt32() && constant.asInt32() == 0)
+        return true;
+
+    return false;
+}
+
+void BinaryOpNode::tryFoldToBranch(BytecodeGenerator& generator, TriState& branchCondition, ExpressionNode*& branchExpression)
+{
+    branchCondition = MixedTriState;
+    branchExpression = 0;
+
+    ConstantNode* constant = 0;
+    if (m_expr1->isConstant()) {
+        constant = static_cast<ConstantNode*>(m_expr1);
+        branchExpression = m_expr2;
+    } else if (m_expr2->isConstant()) {
+        constant = static_cast<ConstantNode*>(m_expr2);
+        branchExpression = m_expr1;
+    }
+
+    if (!constant)
+        return;
+    ASSERT(branchExpression);
+
+    OpcodeID opcodeID = this->opcodeID();
+    JSValue value = constant->jsValue(generator);
+    bool canFoldToBranch = JSC::canFoldToBranch(opcodeID, branchExpression, value);
+    if (!canFoldToBranch)
+        return;
+
+    if (opcodeID == op_eq || opcodeID == op_stricteq)
+        branchCondition = triState(value.pureToBoolean());
+    else if (opcodeID == op_neq || opcodeID == op_nstricteq)
+        branchCondition = triState(!value.pureToBoolean());
+}
+
 RegisterID* BinaryOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     OpcodeID opcodeID = this->opcodeID();
 
-    if (opcodeID == op_add && m_expr1->isAdd() && m_expr1->resultDescriptor().definitelyIsString())
+    if (opcodeID == op_add && m_expr1->isAdd() && m_expr1->resultDescriptor().definitelyIsString()) {
+        generator.emitExpressionInfo(position(), position(), position());
         return emitStrcat(generator, dst);
+    }
 
     if (opcodeID == op_neq) {
         if (m_expr1->isNull() || m_expr2->isNull()) {
@@ -926,9 +1566,31 @@ RegisterID* BinaryOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID*
         }
     }
 
-    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1, m_rightHasAssignments, m_expr2->isPure(generator));
-    RegisterID* src2 = generator.emitNode(m_expr2);
-    return generator.emitBinaryOp(opcodeID, generator.finalDestination(dst, src1.get()), src1.get(), src2, OperandTypes(m_expr1->resultDescriptor(), m_expr2->resultDescriptor()));
+    ExpressionNode* left = m_expr1;
+    ExpressionNode* right = m_expr2;
+    if (opcodeID == op_neq || opcodeID == op_nstricteq) {
+        if (left->isString())
+            std::swap(left, right);
+    }
+
+    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(left, m_rightHasAssignments, right->isPure(generator));
+    bool wasTypeof = generator.lastOpcodeID() == op_typeof;
+    RefPtr<RegisterID> src2 = generator.emitNode(right);
+    generator.emitExpressionInfo(position(), position(), position());
+    if (wasTypeof && (opcodeID == op_neq || opcodeID == op_nstricteq)) {
+        RefPtr<RegisterID> tmp = generator.tempDestination(dst);
+        if (opcodeID == op_neq)
+            generator.emitEqualityOp(op_eq, generator.finalDestination(tmp.get(), src1.get()), src1.get(), src2.get());
+        else if (opcodeID == op_nstricteq)
+            generator.emitEqualityOp(op_stricteq, generator.finalDestination(tmp.get(), src1.get()), src1.get(), src2.get());
+        else
+            RELEASE_ASSERT_NOT_REACHED();
+        return generator.emitUnaryOp(op_not, generator.finalDestination(dst, tmp.get()), tmp.get());
+    }
+    RegisterID* result = generator.emitBinaryOp(opcodeID, generator.finalDestination(dst, src1.get()), src1.get(), src2.get(), OperandTypes(left->resultDescriptor(), right->resultDescriptor()));
+    if (opcodeID == op_urshift && dst != generator.ignoredResult())
+        return generator.emitUnaryOp(op_unsigned, result, result);
+    return result;
 }
 
 RegisterID* EqualNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
@@ -939,44 +1601,54 @@ RegisterID* EqualNode::emitBytecode(BytecodeGenerator& generator, RegisterID* ds
         return generator.emitUnaryOp(op_eq_null, generator.finalDestination(dst, src.get()), src.get());
     }
 
-    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1, m_rightHasAssignments, m_expr2->isPure(generator));
-    RegisterID* src2 = generator.emitNode(m_expr2);
-    return generator.emitEqualityOp(op_eq, generator.finalDestination(dst, src1.get()), src1.get(), src2);
+    ExpressionNode* left = m_expr1;
+    ExpressionNode* right = m_expr2;
+    if (left->isString())
+        std::swap(left, right);
+
+    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(left, m_rightHasAssignments, m_expr2->isPure(generator));
+    RefPtr<RegisterID> src2 = generator.emitNode(right);
+    return generator.emitEqualityOp(op_eq, generator.finalDestination(dst, src1.get()), src1.get(), src2.get());
 }
 
 RegisterID* StrictEqualNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1, m_rightHasAssignments, m_expr2->isPure(generator));
-    RegisterID* src2 = generator.emitNode(m_expr2);
-    return generator.emitEqualityOp(op_stricteq, generator.finalDestination(dst, src1.get()), src1.get(), src2);
-}
+    ExpressionNode* left = m_expr1;
+    ExpressionNode* right = m_expr2;
+    if (left->isString())
+        std::swap(left, right);
 
-RegisterID* ReverseBinaryOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
-{
-    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1, m_rightHasAssignments, m_expr2->isPure(generator));
-    RegisterID* src2 = generator.emitNode(m_expr2);
-    return generator.emitBinaryOp(opcodeID(), generator.finalDestination(dst, src1.get()), src2, src1.get(), OperandTypes(m_expr2->resultDescriptor(), m_expr1->resultDescriptor()));
+    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(left, m_rightHasAssignments, m_expr2->isPure(generator));
+    RefPtr<RegisterID> src2 = generator.emitNode(right);
+    return generator.emitEqualityOp(op_stricteq, generator.finalDestination(dst, src1.get()), src1.get(), src2.get());
 }
 
 RegisterID* ThrowableBinaryOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1, m_rightHasAssignments, m_expr2->isPure(generator));
-    RegisterID* src2 = generator.emitNode(m_expr2);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    return generator.emitBinaryOp(opcodeID(), generator.finalDestination(dst, src1.get()), src1.get(), src2, OperandTypes(m_expr1->resultDescriptor(), m_expr2->resultDescriptor()));
+    RefPtr<RegisterID> src2 = generator.emitNode(m_expr2);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    return generator.emitBinaryOp(opcodeID(), generator.finalDestination(dst, src1.get()), src1.get(), src2.get(), OperandTypes(m_expr1->resultDescriptor(), m_expr2->resultDescriptor()));
 }
 
 RegisterID* InstanceOfNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1, m_rightHasAssignments, m_expr2->isPure(generator));
     RefPtr<RegisterID> src2 = generator.emitNode(m_expr2);
+    RefPtr<RegisterID> prototype = generator.newTemporary();
+    RefPtr<RegisterID> dstReg = generator.finalDestination(dst, src1.get());
+    RefPtr<Label> target = generator.newLabel();
+
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    generator.emitCheckHasInstance(dstReg.get(), src1.get(), src2.get(), target.get());
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    generator.emitGetByIdExceptionInfo(op_instanceof);
-    RegisterID* src2Prototype = generator.emitGetById(generator.newTemporary(), src2.get(), generator.globalData()->propertyNames->prototype);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    generator.emitGetById(prototype.get(), src2.get(), generator.vm()->propertyNames->prototype);
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    return generator.emitInstanceOf(generator.finalDestination(dst, src1.get()), src1.get(), src2.get(), src2Prototype);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RegisterID* result = generator.emitInstanceOf(dstReg.get(), src1.get(), prototype.get());
+    generator.emitLabel(target.get());
+    return result;
 }
 
 // ------------------------------ LogicalOpNode ----------------------------
@@ -997,32 +1669,16 @@ RegisterID* LogicalOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID
     return generator.moveToDestinationIfNeeded(dst, temp.get());
 }
 
-void LogicalOpNode::emitBytecodeInConditionContext(BytecodeGenerator& generator, Label* trueTarget, Label* falseTarget, bool fallThroughMeansTrue)
+void LogicalOpNode::emitBytecodeInConditionContext(BytecodeGenerator& generator, Label* trueTarget, Label* falseTarget, FallThroughMode fallThroughMode)
 {
-    if (m_expr1->hasConditionContextCodegen()) {
-        RefPtr<Label> afterExpr1 = generator.newLabel();
-        if (m_operator == OpLogicalAnd)
-            generator.emitNodeInConditionContext(m_expr1, afterExpr1.get(), falseTarget, true);
-        else 
-            generator.emitNodeInConditionContext(m_expr1, trueTarget, afterExpr1.get(), false);
-        generator.emitLabel(afterExpr1.get());
-    } else {
-        RegisterID* temp = generator.emitNode(m_expr1);
-        if (m_operator == OpLogicalAnd)
-            generator.emitJumpIfFalse(temp, falseTarget);
-        else
-            generator.emitJumpIfTrue(temp, trueTarget);
-    }
+    RefPtr<Label> afterExpr1 = generator.newLabel();
+    if (m_operator == OpLogicalAnd)
+        generator.emitNodeInConditionContext(m_expr1, afterExpr1.get(), falseTarget, FallThroughMeansTrue);
+    else 
+        generator.emitNodeInConditionContext(m_expr1, trueTarget, afterExpr1.get(), FallThroughMeansFalse);
+    generator.emitLabel(afterExpr1.get());
 
-    if (m_expr2->hasConditionContextCodegen())
-        generator.emitNodeInConditionContext(m_expr2, trueTarget, falseTarget, fallThroughMeansTrue);
-    else {
-        RegisterID* temp = generator.emitNode(m_expr2);
-        if (fallThroughMeansTrue)
-            generator.emitJumpIfFalse(temp, falseTarget);
-        else
-            generator.emitJumpIfTrue(temp, trueTarget);
-    }
+    generator.emitNodeInConditionContext(m_expr2, trueTarget, falseTarget, fallThroughMode);
 }
 
 // ------------------------------ ConditionalNode ------------------------------
@@ -1033,23 +1689,22 @@ RegisterID* ConditionalNode::emitBytecode(BytecodeGenerator& generator, Register
     RefPtr<Label> beforeElse = generator.newLabel();
     RefPtr<Label> afterElse = generator.newLabel();
 
-    if (m_logical->hasConditionContextCodegen()) {
-        RefPtr<Label> beforeThen = generator.newLabel();
-        generator.emitNodeInConditionContext(m_logical, beforeThen.get(), beforeElse.get(), true);
-        generator.emitLabel(beforeThen.get());
-    } else {
-        RegisterID* cond = generator.emitNode(m_logical);
-        generator.emitJumpIfFalse(cond, beforeElse.get());
-    }
+    RefPtr<Label> beforeThen = generator.newLabel();
+    generator.emitNodeInConditionContext(m_logical, beforeThen.get(), beforeElse.get(), FallThroughMeansTrue);
+    generator.emitLabel(beforeThen.get());
 
+    generator.emitProfileControlFlow(m_expr1->startOffset());
     generator.emitNode(newDst.get(), m_expr1);
     generator.emitJump(afterElse.get());
 
     generator.emitLabel(beforeElse.get());
+    generator.emitProfileControlFlow(m_expr1->endOffset() + 1);
     generator.emitNode(newDst.get(), m_expr2);
 
     generator.emitLabel(afterElse.get());
 
+    generator.emitProfileControlFlow(m_expr2->endOffset() + 1);
+
     return newDst.get();
 }
 
@@ -1096,7 +1751,7 @@ static ALWAYS_INLINE RegisterID* emitReadModifyAssignment(BytecodeGenerator& gen
             opcodeID = op_mod;
             break;
         default:
-            ASSERT_NOT_REACHED();
+            RELEASE_ASSERT_NOT_REACHED();
             return dst;
     }
 
@@ -1105,76 +1760,89 @@ static ALWAYS_INLINE RegisterID* emitReadModifyAssignment(BytecodeGenerator& gen
     // Certain read-modify nodes require expression info to be emitted *after* m_right has been generated.
     // If this is required the node is passed as 'emitExpressionInfoForMe'; do so now.
     if (emitExpressionInfoForMe)
-        generator.emitExpressionInfo(emitExpressionInfoForMe->divot(), emitExpressionInfoForMe->startOffset(), emitExpressionInfoForMe->endOffset());
-
-    return generator.emitBinaryOp(opcodeID, dst, src1, src2, types);
+        generator.emitExpressionInfo(emitExpressionInfoForMe->divot(), emitExpressionInfoForMe->divotStart(), emitExpressionInfoForMe->divotEnd());
+    RegisterID* result = generator.emitBinaryOp(opcodeID, dst, src1, src2, types);
+    if (oper == OpURShift)
+        return generator.emitUnaryOp(op_unsigned, result, result);
+    return result;
 }
 
 RegisterID* ReadModifyResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (RegisterID* local = generator.registerFor(m_ident)) {
-        if (generator.isLocalConstant(m_ident)) {
+    JSTextPosition newDivot = divotStart() + m_ident.length();
+    Variable var = generator.variable(m_ident);
+    if (RegisterID* local = var.local()) {
+        if (var.isReadOnly()) {
+            generator.emitReadOnlyExceptionIfNeeded();
             return emitReadModifyAssignment(generator, generator.finalDestination(dst), local, m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
         }
         
-        if (generator.leftHandSideNeedsCopy(m_rightHasAssignments, m_right->isPure(generator))) {
+        if (generator.vm()->typeProfiler()
+            || generator.leftHandSideNeedsCopy(m_rightHasAssignments, m_right->isPure(generator))) {
             RefPtr<RegisterID> result = generator.newTemporary();
             generator.emitMove(result.get(), local);
             emitReadModifyAssignment(generator, result.get(), result.get(), m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
             generator.emitMove(local, result.get());
+            generator.invalidateForInContextForLocal(local);
+            if (generator.vm()->typeProfiler())
+                generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
             return generator.moveToDestinationIfNeeded(dst, result.get());
         }
         
         RegisterID* result = emitReadModifyAssignment(generator, local, local, m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
+        generator.invalidateForInContextForLocal(local);
         return generator.moveToDestinationIfNeeded(dst, result);
     }
 
-    int index = 0;
-    size_t depth = 0;
-    JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, true, globalObject) && index != missingSymbolMarker()) {
-        RefPtr<RegisterID> src1 = generator.emitGetScopedVar(generator.tempDestination(dst), depth, index, globalObject);
-        RegisterID* result = emitReadModifyAssignment(generator, generator.finalDestination(dst, src1.get()), src1.get(), m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
-        generator.emitPutScopedVar(depth, index, result, globalObject);
-        return result;
+    generator.emitExpressionInfo(newDivot, divotStart(), newDivot);
+    RefPtr<RegisterID> scope = generator.emitResolveScope(nullptr, var);
+    RefPtr<RegisterID> value = generator.emitGetFromScope(generator.newTemporary(), scope.get(), var, ThrowIfNotFound);
+    RefPtr<RegisterID> result = emitReadModifyAssignment(generator, generator.finalDestination(dst, value.get()), value.get(), m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()), this);
+    RegisterID* returnResult = generator.emitPutToScope(scope.get(), var, result.get(), ThrowIfNotFound);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(result.get(), var.isResolved() ? ProfileTypeBytecodePutToLocalScope : ProfileTypeBytecodePutToScope, &m_ident);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
     }
-
-    RefPtr<RegisterID> src1 = generator.tempDestination(dst);
-    generator.emitExpressionInfo(divot() - startOffset() + m_ident.size(), m_ident.size(), 0);
-    RefPtr<RegisterID> base = generator.emitResolveWithBase(generator.newTemporary(), src1.get(), m_ident);
-    RegisterID* result = emitReadModifyAssignment(generator, generator.finalDestination(dst, src1.get()), src1.get(), m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()), this);
-    return generator.emitPutById(base.get(), m_ident, result);
+    return returnResult;
 }
 
 // ------------------------------ AssignResolveNode -----------------------------------
 
 RegisterID* AssignResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (RegisterID* local = generator.registerFor(m_ident)) {
-        if (generator.isLocalConstant(m_ident))
+    Variable var = generator.variable(m_ident);
+    if (RegisterID* local = var.local()) {
+        if (var.isReadOnly()) {
+            generator.emitReadOnlyExceptionIfNeeded();
             return generator.emitNode(dst, m_right);
-        
+        }
+        if (var.isSpecial() || generator.vm()->typeProfiler()) {
+            RefPtr<RegisterID> tempDst = generator.tempDestination(dst);
+            generator.emitNode(tempDst.get(), m_right);
+            generator.emitMove(local, tempDst.get());
+            generator.invalidateForInContextForLocal(local);
+            if (generator.vm()->typeProfiler())
+                generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+            return generator.moveToDestinationIfNeeded(dst, tempDst.get());
+        }
         RegisterID* result = generator.emitNode(local, m_right);
+        generator.invalidateForInContextForLocal(local);
         return generator.moveToDestinationIfNeeded(dst, result);
     }
 
-    int index = 0;
-    size_t depth = 0;
-    JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, true, globalObject) && index != missingSymbolMarker()) {
-        if (dst == generator.ignoredResult())
-            dst = 0;
-        RegisterID* value = generator.emitNode(dst, m_right);
-        generator.emitPutScopedVar(depth, index, value, globalObject);
-        return value;
-    }
-
-    RefPtr<RegisterID> base = generator.emitResolveBase(generator.newTemporary(), m_ident);
+    if (generator.isStrictMode())
+        generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RefPtr<RegisterID> scope = generator.emitResolveScope(nullptr, var);
     if (dst == generator.ignoredResult())
         dst = 0;
-    RegisterID* value = generator.emitNode(dst, m_right);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    return generator.emitPutById(base.get(), m_ident, value);
+    RefPtr<RegisterID> result = generator.emitNode(dst, m_right);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RegisterID* returnResult = generator.emitPutToScope(scope.get(), var, result.get(), generator.isStrictMode() ? ThrowIfNotFound : DoNotThrowIfNotFound);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(result.get(), var.isResolved() ? ProfileTypeBytecodePutToLocalScope : ProfileTypeBytecodePutToScope, &m_ident);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    } 
+    return returnResult;
 }
 
 // ------------------------------ AssignDotNode -----------------------------------
@@ -1183,10 +1851,15 @@ RegisterID* AssignDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID
 {
     RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base, m_rightHasAssignments, m_right->isPure(generator));
     RefPtr<RegisterID> value = generator.destinationForAssignResult(dst);
-    RegisterID* result = generator.emitNode(value.get(), m_right);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    generator.emitPutById(base.get(), m_ident, result);
-    return generator.moveToDestinationIfNeeded(dst, result);
+    RefPtr<RegisterID> result = generator.emitNode(value.get(), m_right);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RegisterID* forwardResult = (dst == generator.ignoredResult()) ? result.get() : generator.moveToDestinationIfNeeded(generator.tempDestination(result.get()), result.get());
+    generator.emitPutById(base.get(), m_ident, forwardResult);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(forwardResult, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return generator.moveToDestinationIfNeeded(dst, forwardResult);
 }
 
 // ------------------------------ ReadModifyDotNode -----------------------------------
@@ -1195,19 +1868,24 @@ RegisterID* ReadModifyDotNode::emitBytecode(BytecodeGenerator& generator, Regist
 {
     RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base, m_rightHasAssignments, m_right->isPure(generator));
 
-    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
+    generator.emitExpressionInfo(subexpressionDivot(), subexpressionStart(), subexpressionEnd());
     RefPtr<RegisterID> value = generator.emitGetById(generator.tempDestination(dst), base.get(), m_ident);
-    RegisterID* updatedValue = emitReadModifyAssignment(generator, generator.finalDestination(dst, value.get()), value.get(), m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
+    RegisterID* updatedValue = emitReadModifyAssignment(generator, generator.finalDestination(dst, value.get()), value.get(), m_right, static_cast<JSC::Operator>(m_operator), OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    return generator.emitPutById(base.get(), m_ident, updatedValue);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RegisterID* ret = generator.emitPutById(base.get(), m_ident, updatedValue);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(updatedValue, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return ret;
 }
 
 // ------------------------------ AssignErrorNode -----------------------------------
 
 RegisterID* AssignErrorNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
 {
-    return emitThrowError(generator, ReferenceError, "Left side of assignment is not a reference.");
+    return emitThrowReferenceError(generator, ASCIILiteral("Left side of assignment is not a reference."));
 }
 
 // ------------------------------ AssignBracketNode -----------------------------------
@@ -1217,11 +1895,21 @@ RegisterID* AssignBracketNode::emitBytecode(BytecodeGenerator& generator, Regist
     RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base, m_subscriptHasAssignments || m_rightHasAssignments, m_subscript->isPure(generator) && m_right->isPure(generator));
     RefPtr<RegisterID> property = generator.emitNodeForLeftHandSide(m_subscript, m_rightHasAssignments, m_right->isPure(generator));
     RefPtr<RegisterID> value = generator.destinationForAssignResult(dst);
-    RegisterID* result = generator.emitNode(value.get(), m_right);
+    RefPtr<RegisterID> result = generator.emitNode(value.get(), m_right);
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-    generator.emitPutByVal(base.get(), property.get(), result);
-    return generator.moveToDestinationIfNeeded(dst, result);
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+    RegisterID* forwardResult = (dst == generator.ignoredResult()) ? result.get() : generator.moveToDestinationIfNeeded(generator.tempDestination(result.get()), result.get());
+
+    if (m_subscript->isString())
+        generator.emitPutById(base.get(), static_cast<StringNode*>(m_subscript)->value(), forwardResult);
+    else
+        generator.emitPutByVal(base.get(), property.get(), forwardResult);
+
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(forwardResult, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return generator.moveToDestinationIfNeeded(dst, forwardResult);
 }
 
 // ------------------------------ ReadModifyBracketNode -----------------------------------
@@ -1231,12 +1919,16 @@ RegisterID* ReadModifyBracketNode::emitBytecode(BytecodeGenerator& generator, Re
     RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base, m_subscriptHasAssignments || m_rightHasAssignments, m_subscript->isPure(generator) && m_right->isPure(generator));
     RefPtr<RegisterID> property = generator.emitNodeForLeftHandSide(m_subscript, m_rightHasAssignments, m_right->isPure(generator));
 
-    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
+    generator.emitExpressionInfo(subexpressionDivot(), subexpressionStart(), subexpressionEnd());
     RefPtr<RegisterID> value = generator.emitGetByVal(generator.tempDestination(dst), base.get(), property.get());
-    RegisterID* updatedValue = emitReadModifyAssignment(generator, generator.finalDestination(dst, value.get()), value.get(), m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
+    RegisterID* updatedValue = emitReadModifyAssignment(generator, generator.finalDestination(dst, value.get()), value.get(), m_right, static_cast<JSC::Operator>(m_operator), OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
 
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
     generator.emitPutByVal(base.get(), property.get(), updatedValue);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(updatedValue, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
 
     return updatedValue;
 }
@@ -1245,34 +1937,55 @@ RegisterID* ReadModifyBracketNode::emitBytecode(BytecodeGenerator& generator, Re
 
 RegisterID* CommaNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    ASSERT(m_expressions.size() > 1);
-    for (size_t i = 0; i < m_expressions.size() - 1; i++)
-        generator.emitNode(generator.ignoredResult(), m_expressions[i]);
-    return generator.emitNode(dst, m_expressions.last());
+    CommaNode* node = this;
+    for (; node && node->next(); node = node->next())
+        generator.emitNode(generator.ignoredResult(), node->m_expr);
+    return generator.emitNode(dst, node->m_expr);
 }
 
 // ------------------------------ ConstDeclNode ------------------------------------
 
 RegisterID* ConstDeclNode::emitCodeSingle(BytecodeGenerator& generator)
 {
-    if (RegisterID* local = generator.constRegisterFor(m_ident)) {
+    // FIXME: This code does not match the behavior of const in Firefox.
+    Variable var = generator.variable(m_ident);
+    if (RegisterID* local = var.local()) {
         if (!m_init)
             return local;
 
+        // FIXME: Maybe call emitExpressionInfo here.
+        if (var.isSpecial() || generator.vm()->typeProfiler()) {
+            RefPtr<RegisterID> tempDst = generator.newTemporary();
+            generator.emitNode(tempDst.get(), m_init);
+            return generator.emitMove(local, tempDst.get());
+        }
+        
         return generator.emitNode(local, m_init);
     }
 
+    RefPtr<RegisterID> value = m_init ? generator.emitNode(m_init) : generator.emitLoad(0, jsUndefined());
+
+    if (generator.codeType() == GlobalCode)
+        return generator.emitInitGlobalConst(m_ident, value.get());
+
     if (generator.codeType() != EvalCode) {
-        if (m_init)
-            return generator.emitNode(m_init);
-        else
-            return generator.emitResolve(generator.newTemporary(), m_ident);
+        // Do a special kind of resolution. If anything fails, then don't perform the assignment. This is
+        // pretty shady - particularly how negligent it is with inteleaving scopes - but it's the
+        // behavior that JSC has had for a long time.
+        
+        ASSERT(generator.codeType() == FunctionCode);
+        
+        var = generator.variablePerSymbolTable(m_ident);
+        if (!var.isResolved())
+            return value.get();
+        
+        RefPtr<RegisterID> scope = generator.emitResolveScope(generator.newTemporary(), var);
+        return generator.emitPutToScope(scope.get(), var, value.get(), DoNotThrowIfNotFound);
     }
-    // FIXME: While this code should only be hit in eval code, it will potentially
-    // assign to the wrong base if m_ident exists in an intervening dynamic scope.
-    RefPtr<RegisterID> base = generator.emitResolveBase(generator.newTemporary(), m_ident);
-    RegisterID* value = m_init ? generator.emitNode(m_init) : generator.emitLoad(0, jsUndefined());
-    return generator.emitPutById(base.get(), m_ident, value);
+
+    // FIXME: This will result in incorrect assignment if m_ident exists in an intervening with scope.
+    RefPtr<RegisterID> scope = generator.emitResolveScope(nullptr, var);
+    return generator.emitPutToScope(scope.get(), var, value.get(), DoNotThrowIfNotFound);
 }
 
 RegisterID* ConstDeclNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
@@ -1286,10 +1999,10 @@ RegisterID* ConstDeclNode::emitBytecode(BytecodeGenerator& generator, RegisterID
 
 // ------------------------------ ConstStatementNode -----------------------------
 
-RegisterID* ConstStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+void ConstStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-    return generator.emitNode(m_next);
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
+    generator.emitNode(m_next);
 }
 
 // ------------------------------ SourceElements -------------------------------
@@ -1297,15 +2010,13 @@ RegisterID* ConstStatementNode::emitBytecode(BytecodeGenerator& generator, Regis
 
 inline StatementNode* SourceElements::lastStatement() const
 {
-    size_t size = m_statements.size();
-    return size ? m_statements[size - 1] : 0;
+    return m_tail;
 }
 
 inline void SourceElements::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    size_t size = m_statements.size();
-    for (size_t i = 0; i < size; ++i)
-        generator.emitNode(dst, m_statements[i]);
+    for (StatementNode* statement = m_head; statement; statement = statement->next())
+        generator.emitNode(dst, statement);
 }
 
 // ------------------------------ BlockNode ------------------------------------
@@ -1315,353 +2026,635 @@ inline StatementNode* BlockNode::lastStatement() const
     return m_statements ? m_statements->lastStatement() : 0;
 }
 
-RegisterID* BlockNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+StatementNode* BlockNode::singleStatement() const
 {
-    if (m_statements)
-        m_statements->emitBytecode(generator, dst);
-    return 0;
+    return m_statements ? m_statements->singleStatement() : 0;
+}
+
+void BlockNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    if (!m_statements)
+        return;
+    m_statements->emitBytecode(generator, dst);
 }
 
 // ------------------------------ EmptyStatementNode ---------------------------
 
-RegisterID* EmptyStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void EmptyStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-    return dst;
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
 }
 
 // ------------------------------ DebuggerStatementNode ---------------------------
 
-RegisterID* DebuggerStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void DebuggerStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
 {
-    generator.emitDebugHook(DidReachBreakpoint, firstLine(), lastLine());
-    return dst;
+    generator.emitDebugHook(DidReachBreakpoint, lastLine(), startOffset(), lineStartOffset());
 }
 
 // ------------------------------ ExprStatementNode ----------------------------
 
-RegisterID* ExprStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void ExprStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     ASSERT(m_expr);
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine()); 
-    return generator.emitNode(dst, m_expr);
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
+    generator.emitNode(dst, m_expr);
 }
 
 // ------------------------------ VarStatementNode ----------------------------
 
-RegisterID* VarStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+void VarStatementNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
 {
     ASSERT(m_expr);
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-    return generator.emitNode(m_expr);
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
+    generator.emitNode(m_expr);
 }
 
-// ------------------------------ IfNode ---------------------------------------
+// ------------------------------ EmptyVarExpression ----------------------------
 
-RegisterID* IfNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* EmptyVarExpression::emitBytecode(BytecodeGenerator& generator, RegisterID*)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-    
-    RefPtr<Label> afterThen = generator.newLabel();
+    if (!generator.vm()->typeProfiler())
+        return nullptr;
 
-    if (m_condition->hasConditionContextCodegen()) {
-        RefPtr<Label> beforeThen = generator.newLabel();
-        generator.emitNodeInConditionContext(m_condition, beforeThen.get(), afterThen.get(), true);
-        generator.emitLabel(beforeThen.get());
-    } else {
-        RegisterID* cond = generator.emitNode(m_condition);
-        generator.emitJumpIfFalse(cond, afterThen.get());
+    Variable var = generator.variable(m_ident);
+    if (RegisterID* local = var.local())
+        generator.emitProfileType(local, ProfileTypeBytecodeHasGlobalID, nullptr);
+    else {
+        RefPtr<RegisterID> scope = generator.emitResolveScope(nullptr, var);
+        RefPtr<RegisterID> value = generator.emitGetFromScope(generator.newTemporary(), scope.get(), var, DoNotThrowIfNotFound);
+        generator.emitProfileType(value.get(), var.isResolved() ? ProfileTypeBytecodeGetFromLocalScope : ProfileTypeBytecodeGetFromScope, &m_ident);
     }
 
-    generator.emitNode(dst, m_ifBlock);
-    generator.emitLabel(afterThen.get());
+    generator.emitTypeProfilerExpressionInfo(position(), JSTextPosition(-1, position().offset + m_ident.length(), -1));
 
-    // FIXME: This should return the last statement executed so that it can be returned as a Completion.
-    return 0;
+    // It's safe to return null here because this node will always be a child node of VarStatementNode which ignores our return value.
+    return nullptr;
 }
 
 // ------------------------------ IfElseNode ---------------------------------------
 
-RegisterID* IfElseNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+static inline StatementNode* singleStatement(StatementNode* statementNode)
+{
+    if (statementNode->isBlock())
+        return static_cast<BlockNode*>(statementNode)->singleStatement();
+    return statementNode;
+}
+
+bool IfElseNode::tryFoldBreakAndContinue(BytecodeGenerator& generator, StatementNode* ifBlock,
+    Label*& trueTarget, FallThroughMode& fallThroughMode)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
+    StatementNode* singleStatement = JSC::singleStatement(ifBlock);
+    if (!singleStatement)
+        return false;
+
+    if (singleStatement->isBreak()) {
+        BreakNode* breakNode = static_cast<BreakNode*>(singleStatement);
+        Label* target = breakNode->trivialTarget(generator);
+        if (!target)
+            return false;
+        trueTarget = target;
+        fallThroughMode = FallThroughMeansFalse;
+        return true;
+    }
+
+    if (singleStatement->isContinue()) {
+        ContinueNode* continueNode = static_cast<ContinueNode*>(singleStatement);
+        Label* target = continueNode->trivialTarget(generator);
+        if (!target)
+            return false;
+        trueTarget = target;
+        fallThroughMode = FallThroughMeansFalse;
+        return true;
+    }
+
+    return false;
+}
+
+void IfElseNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
     
+    RefPtr<Label> beforeThen = generator.newLabel();
     RefPtr<Label> beforeElse = generator.newLabel();
     RefPtr<Label> afterElse = generator.newLabel();
 
-    if (m_condition->hasConditionContextCodegen()) {
-        RefPtr<Label> beforeThen = generator.newLabel();
-        generator.emitNodeInConditionContext(m_condition, beforeThen.get(), beforeElse.get(), true);
-        generator.emitLabel(beforeThen.get());
-    } else {
-        RegisterID* cond = generator.emitNode(m_condition);
-        generator.emitJumpIfFalse(cond, beforeElse.get());
-    }
+    Label* trueTarget = beforeThen.get();
+    Label* falseTarget = beforeElse.get();
+    FallThroughMode fallThroughMode = FallThroughMeansTrue;
+    bool didFoldIfBlock = tryFoldBreakAndContinue(generator, m_ifBlock, trueTarget, fallThroughMode);
 
-    generator.emitNode(dst, m_ifBlock);
-    generator.emitJump(afterElse.get());
+    generator.emitNodeInConditionContext(m_condition, trueTarget, falseTarget, fallThroughMode);
+    generator.emitLabel(beforeThen.get());
+    generator.emitProfileControlFlow(m_ifBlock->startOffset());
+
+    if (!didFoldIfBlock) {
+        generator.emitNode(dst, m_ifBlock);
+        if (m_elseBlock)
+            generator.emitJump(afterElse.get());
+    }
 
     generator.emitLabel(beforeElse.get());
 
-    generator.emitNode(dst, m_elseBlock);
+    if (m_elseBlock) {
+        generator.emitProfileControlFlow(m_ifBlock->endOffset() + (m_ifBlock->isBlock() ? 1 : 0));
+        generator.emitNode(dst, m_elseBlock);
+    }
 
     generator.emitLabel(afterElse.get());
-
-    // FIXME: This should return the last statement executed so that it can be returned as a Completion.
-    return 0;
+    StatementNode* endingBlock = m_elseBlock ? m_elseBlock : m_ifBlock;
+    generator.emitProfileControlFlow(endingBlock->endOffset() + (endingBlock->isBlock() ? 1 : 0));
 }
 
 // ------------------------------ DoWhileNode ----------------------------------
 
-RegisterID* DoWhileNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void DoWhileNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<LabelScope> scope = generator.newLabelScope(LabelScope::Loop);
+    LabelScopePtr scope = generator.newLabelScope(LabelScope::Loop);
 
     RefPtr<Label> topOfLoop = generator.newLabel();
     generator.emitLabel(topOfLoop.get());
+    generator.emitLoopHint();
+    generator.emitDebugHook(WillExecuteStatement, lastLine(), startOffset(), lineStartOffset());
 
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-   
-    RefPtr<RegisterID> result = generator.emitNode(dst, m_statement);
+    generator.emitNode(dst, m_statement);
 
     generator.emitLabel(scope->continueTarget());
-    generator.emitDebugHook(WillExecuteStatement, m_expr->lineNo(), m_expr->lineNo());
-    if (m_expr->hasConditionContextCodegen())
-        generator.emitNodeInConditionContext(m_expr, topOfLoop.get(), scope->breakTarget(), false);
-    else {
-        RegisterID* cond = generator.emitNode(m_expr);
-        generator.emitJumpIfTrue(cond, topOfLoop.get());
-    }
+    generator.emitDebugHook(WillExecuteStatement, lastLine(), startOffset(), lineStartOffset());
+    generator.emitNodeInConditionContext(m_expr, topOfLoop.get(), scope->breakTarget(), FallThroughMeansFalse);
 
     generator.emitLabel(scope->breakTarget());
-    return result.get();
 }
 
 // ------------------------------ WhileNode ------------------------------------
 
-RegisterID* WhileNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void WhileNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<LabelScope> scope = generator.newLabelScope(LabelScope::Loop);
+    LabelScopePtr scope = generator.newLabelScope(LabelScope::Loop);
+    RefPtr<Label> topOfLoop = generator.newLabel();
 
-    generator.emitJump(scope->continueTarget());
+    generator.emitDebugHook(WillExecuteStatement, m_expr->firstLine(), m_expr->startOffset(), m_expr->lineStartOffset());
+    generator.emitNodeInConditionContext(m_expr, topOfLoop.get(), scope->breakTarget(), FallThroughMeansTrue);
 
-    RefPtr<Label> topOfLoop = generator.newLabel();
     generator.emitLabel(topOfLoop.get());
+    generator.emitLoopHint();
     
+    generator.emitProfileControlFlow(m_statement->startOffset());
     generator.emitNode(dst, m_statement);
 
     generator.emitLabel(scope->continueTarget());
-    generator.emitDebugHook(WillExecuteStatement, m_expr->lineNo(), m_expr->lineNo());
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
 
-    if (m_expr->hasConditionContextCodegen())
-        generator.emitNodeInConditionContext(m_expr, topOfLoop.get(), scope->breakTarget(), false);
-    else {
-        RegisterID* cond = generator.emitNode(m_expr);
-        generator.emitJumpIfTrue(cond, topOfLoop.get());
-    }
+    generator.emitNodeInConditionContext(m_expr, topOfLoop.get(), scope->breakTarget(), FallThroughMeansFalse);
 
     generator.emitLabel(scope->breakTarget());
-    
-    // FIXME: This should return the last statement executed so that it can be returned as a Completion
-    return 0;
+
+    generator.emitProfileControlFlow(m_statement->endOffset() + (m_statement->isBlock() ? 1 : 0));
 }
 
 // ------------------------------ ForNode --------------------------------------
 
-RegisterID* ForNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void ForNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    RefPtr<LabelScope> scope = generator.newLabelScope(LabelScope::Loop);
+    LabelScopePtr scope = generator.newLabelScope(LabelScope::Loop);
 
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
 
     if (m_expr1)
         generator.emitNode(generator.ignoredResult(), m_expr1);
-
-    RefPtr<Label> condition = generator.newLabel();
-    generator.emitJump(condition.get());
-
+    
     RefPtr<Label> topOfLoop = generator.newLabel();
+    if (m_expr2)
+        generator.emitNodeInConditionContext(m_expr2, topOfLoop.get(), scope->breakTarget(), FallThroughMeansTrue);
+
     generator.emitLabel(topOfLoop.get());
+    generator.emitLoopHint();
+    generator.emitProfileControlFlow(m_statement->startOffset());
 
-    RefPtr<RegisterID> result = generator.emitNode(dst, m_statement);
+    generator.emitNode(dst, m_statement);
 
     generator.emitLabel(scope->continueTarget());
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
     if (m_expr3)
         generator.emitNode(generator.ignoredResult(), m_expr3);
 
-    generator.emitLabel(condition.get());
-    if (m_expr2) {
-        if (m_expr2->hasConditionContextCodegen())
-            generator.emitNodeInConditionContext(m_expr2, topOfLoop.get(), scope->breakTarget(), false);
-        else {
-            RegisterID* cond = generator.emitNode(m_expr2);
-            generator.emitJumpIfTrue(cond, topOfLoop.get());
-        }
-    } else
+    if (m_expr2)
+        generator.emitNodeInConditionContext(m_expr2, topOfLoop.get(), scope->breakTarget(), FallThroughMeansFalse);
+    else
         generator.emitJump(topOfLoop.get());
 
     generator.emitLabel(scope->breakTarget());
-    return result.get();
+    generator.emitProfileControlFlow(m_statement->endOffset() + (m_statement->isBlock() ? 1 : 0));
 }
 
 // ------------------------------ ForInNode ------------------------------------
 
-RegisterID* ForInNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+RegisterID* ForInNode::tryGetBoundLocal(BytecodeGenerator& generator)
 {
-    RefPtr<LabelScope> scope = generator.newLabelScope(LabelScope::Loop);
-
-    if (!m_lexpr->isLocation())
-        return emitThrowError(generator, ReferenceError, "Left side of for-in statement is not a reference.");
-
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-
-    if (m_init)
-        generator.emitNode(generator.ignoredResult(), m_init);
+    if (m_lexpr->isResolveNode()) {
+        const Identifier& ident = static_cast<ResolveNode*>(m_lexpr)->identifier();
+        return generator.variable(ident).local();
+    }
 
-    RefPtr<RegisterID> base = generator.newTemporary();
-    generator.emitNode(base.get(), m_expr);
-    RefPtr<RegisterID> i = generator.newTemporary();
-    RefPtr<RegisterID> size = generator.newTemporary();
-    RefPtr<RegisterID> expectedSubscript;
-    RefPtr<RegisterID> iter = generator.emitGetPropertyNames(generator.newTemporary(), base.get(), i.get(), size.get(), scope->breakTarget());
-    generator.emitJump(scope->continueTarget());
+    if (m_lexpr->isDestructuringNode()) {
+        DestructuringAssignmentNode* assignNode = static_cast<DestructuringAssignmentNode*>(m_lexpr);
+        auto binding = assignNode->bindings();
+        if (!binding->isBindingNode())
+            return nullptr;
+
+        auto simpleBinding = static_cast<BindingNode*>(binding);
+        const Identifier& ident = simpleBinding->boundProperty();
+        Variable var = generator.variable(ident);
+        if (var.isSpecial())
+            return nullptr;
+        return var.local();
+    }
 
-    RefPtr<Label> loopStart = generator.newLabel();
-    generator.emitLabel(loopStart.get());
+    return nullptr;
+}
 
-    RegisterID* propertyName;
-    bool optimizedForinAccess = false;
+void ForInNode::emitLoopHeader(BytecodeGenerator& generator, RegisterID* propertyName)
+{
     if (m_lexpr->isResolveNode()) {
         const Identifier& ident = static_cast<ResolveNode*>(m_lexpr)->identifier();
-        propertyName = generator.registerFor(ident);
-        if (!propertyName) {
-            propertyName = generator.newTemporary();
-            RefPtr<RegisterID> protect = propertyName;
-            RegisterID* base = generator.emitResolveBase(generator.newTemporary(), ident);
-
-            generator.emitExpressionInfo(divot(), startOffset(), endOffset());
-            generator.emitPutById(base, ident, propertyName);
-        } else {
-            expectedSubscript = generator.emitMove(generator.newTemporary(), propertyName);
-            generator.pushOptimisedForIn(expectedSubscript.get(), iter.get(), i.get(), propertyName);
-            optimizedForinAccess = true;
+        Variable var = generator.variable(ident);
+        if (RegisterID* local = var.local())
+            generator.emitMove(local, propertyName);
+        else {
+            if (generator.isStrictMode())
+                generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+            RegisterID* scope = generator.emitResolveScope(nullptr, var);
+            generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+            generator.emitPutToScope(scope, var, propertyName, generator.isStrictMode() ? ThrowIfNotFound : DoNotThrowIfNotFound);
+            if (generator.vm()->typeProfiler())
+                generator.emitProfileType(propertyName, var.isResolved() ? ProfileTypeBytecodePutToLocalScope : ProfileTypeBytecodePutToScope, &ident);
         }
-    } else if (m_lexpr->isDotAccessorNode()) {
+        if (generator.vm()->typeProfiler())
+            generator.emitTypeProfilerExpressionInfo(m_lexpr->position(), JSTextPosition(-1, m_lexpr->position().offset + ident.length(), -1));
+        return;
+    }
+    if (m_lexpr->isDotAccessorNode()) {
         DotAccessorNode* assignNode = static_cast<DotAccessorNode*>(m_lexpr);
         const Identifier& ident = assignNode->identifier();
-        propertyName = generator.newTemporary();
-        RefPtr<RegisterID> protect = propertyName;
         RegisterID* base = generator.emitNode(assignNode->base());
-
-        generator.emitExpressionInfo(assignNode->divot(), assignNode->startOffset(), assignNode->endOffset());
+        generator.emitExpressionInfo(assignNode->divot(), assignNode->divotStart(), assignNode->divotEnd());
         generator.emitPutById(base, ident, propertyName);
-    } else {
-        ASSERT(m_lexpr->isBracketAccessorNode());
+        if (generator.vm()->typeProfiler()) {
+            generator.emitProfileType(propertyName, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+            generator.emitTypeProfilerExpressionInfo(assignNode->divotStart(), assignNode->divotEnd());
+        }
+        return;
+    }
+    if (m_lexpr->isBracketAccessorNode()) {
         BracketAccessorNode* assignNode = static_cast<BracketAccessorNode*>(m_lexpr);
-        propertyName = generator.newTemporary();
-        RefPtr<RegisterID> protect = propertyName;
         RefPtr<RegisterID> base = generator.emitNode(assignNode->base());
         RegisterID* subscript = generator.emitNode(assignNode->subscript());
-        
-        generator.emitExpressionInfo(assignNode->divot(), assignNode->startOffset(), assignNode->endOffset());
+        generator.emitExpressionInfo(assignNode->divot(), assignNode->divotStart(), assignNode->divotEnd());
         generator.emitPutByVal(base.get(), subscript, propertyName);
-    }   
+        if (generator.vm()->typeProfiler()) {
+            generator.emitProfileType(propertyName, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+            generator.emitTypeProfilerExpressionInfo(assignNode->divotStart(), assignNode->divotEnd());
+        }
+        return;
+    }
 
-    generator.emitNode(dst, m_statement);
+    if (m_lexpr->isDestructuringNode()) {
+        DestructuringAssignmentNode* assignNode = static_cast<DestructuringAssignmentNode*>(m_lexpr);
+        auto binding = assignNode->bindings();
+        if (!binding->isBindingNode()) {
+            assignNode->bindings()->bindValue(generator, propertyName);
+            return;
+        }
 
-    if (optimizedForinAccess)
-        generator.popOptimisedForIn();
+        auto simpleBinding = static_cast<BindingNode*>(binding);
+        const Identifier& ident = simpleBinding->boundProperty();
+        Variable var = generator.variable(ident);
+        if (!var.local() || var.isSpecial()) {
+            assignNode->bindings()->bindValue(generator, propertyName);
+            return;
+        }
+        generator.emitMove(var.local(), propertyName);
+        if (generator.vm()->typeProfiler())
+            generator.emitTypeProfilerExpressionInfo(simpleBinding->divotStart(), simpleBinding->divotEnd());
+        return;
+    }
 
-    generator.emitLabel(scope->continueTarget());
-    generator.emitNextPropertyName(propertyName, base.get(), i.get(), size.get(), iter.get(), loopStart.get());
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-    generator.emitLabel(scope->breakTarget());
-    return dst;
+    RELEASE_ASSERT_NOT_REACHED();
+}
+
+void ForInNode::emitMultiLoopBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    if (!m_lexpr->isAssignmentLocation()) {
+        emitThrowReferenceError(generator, ASCIILiteral("Left side of for-in statement is not a reference."));
+        return;
+    }
+
+    RefPtr<Label> end = generator.newLabel();
+
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
+
+    RefPtr<RegisterID> base = generator.newTemporary();
+    RefPtr<RegisterID> length;
+    RefPtr<RegisterID> enumerator;
+    generator.emitNode(base.get(), m_expr);
+    RefPtr<RegisterID> local = this->tryGetBoundLocal(generator);
+    RefPtr<RegisterID> enumeratorIndex;
+
+    int profilerStartOffset = m_statement->startOffset();
+    int profilerEndOffset = m_statement->endOffset() + (m_statement->isBlock() ? 1 : 0);
+
+    enumerator = generator.emitGetPropertyEnumerator(generator.newTemporary(), base.get());
+
+    // Indexed property loop.
+    {
+        LabelScopePtr scope = generator.newLabelScope(LabelScope::Loop);
+        RefPtr<Label> loopStart = generator.newLabel();
+        RefPtr<Label> loopEnd = generator.newLabel();
+
+        length = generator.emitGetEnumerableLength(generator.newTemporary(), enumerator.get());
+        RefPtr<RegisterID> i = generator.emitLoad(generator.newTemporary(), jsNumber(0));
+        RefPtr<RegisterID> propertyName = generator.newTemporary();
+
+        generator.emitLabel(loopStart.get());
+        generator.emitLoopHint();
+
+        RefPtr<RegisterID> result = generator.emitEqualityOp(op_less, generator.newTemporary(), i.get(), length.get());
+        generator.emitJumpIfFalse(result.get(), loopEnd.get());
+        generator.emitHasIndexedProperty(result.get(), base.get(), i.get());
+        generator.emitJumpIfFalse(result.get(), scope->continueTarget());
+
+        generator.emitToIndexString(propertyName.get(), i.get());
+        this->emitLoopHeader(generator, propertyName.get());
+
+        generator.emitProfileControlFlow(profilerStartOffset);
+
+        generator.pushIndexedForInScope(local.get(), i.get());
+        generator.emitNode(dst, m_statement);
+        generator.popIndexedForInScope(local.get());
+
+        generator.emitProfileControlFlow(profilerEndOffset);
+
+        generator.emitLabel(scope->continueTarget());
+        generator.emitInc(i.get());
+        generator.emitJump(loopStart.get());
+
+        generator.emitLabel(scope->breakTarget());
+        generator.emitJump(end.get());
+        generator.emitLabel(loopEnd.get());
+    }
+
+    // Structure property loop.
+    {
+        LabelScopePtr scope = generator.newLabelScope(LabelScope::Loop);
+        RefPtr<Label> loopStart = generator.newLabel();
+        RefPtr<Label> loopEnd = generator.newLabel();
+
+        enumeratorIndex = generator.emitLoad(generator.newTemporary(), jsNumber(0));
+        RefPtr<RegisterID> propertyName = generator.newTemporary();
+        generator.emitEnumeratorStructurePropertyName(propertyName.get(), enumerator.get(), enumeratorIndex.get());
+
+        generator.emitLabel(loopStart.get());
+        generator.emitLoopHint();
+
+        RefPtr<RegisterID> result = generator.emitUnaryOp(op_eq_null, generator.newTemporary(), propertyName.get());
+        generator.emitJumpIfTrue(result.get(), loopEnd.get());
+        generator.emitHasStructureProperty(result.get(), base.get(), propertyName.get(), enumerator.get());
+        generator.emitJumpIfFalse(result.get(), scope->continueTarget());
+
+        this->emitLoopHeader(generator, propertyName.get());
+
+        generator.emitProfileControlFlow(profilerStartOffset);
+
+        generator.pushStructureForInScope(local.get(), enumeratorIndex.get(), propertyName.get(), enumerator.get());
+        generator.emitNode(dst, m_statement);
+        generator.popStructureForInScope(local.get());
+
+        generator.emitProfileControlFlow(profilerEndOffset);
+
+        generator.emitLabel(scope->continueTarget());
+        generator.emitInc(enumeratorIndex.get());
+        generator.emitEnumeratorStructurePropertyName(propertyName.get(), enumerator.get(), enumeratorIndex.get());
+        generator.emitJump(loopStart.get());
+        
+        generator.emitLabel(scope->breakTarget());
+        generator.emitJump(end.get());
+        generator.emitLabel(loopEnd.get());
+    }
+
+    // Generic property loop.
+    {
+        LabelScopePtr scope = generator.newLabelScope(LabelScope::Loop);
+        RefPtr<Label> loopStart = generator.newLabel();
+        RefPtr<Label> loopEnd = generator.newLabel();
+
+        RefPtr<RegisterID> propertyName = generator.newTemporary();
+
+        generator.emitEnumeratorGenericPropertyName(propertyName.get(), enumerator.get(), enumeratorIndex.get());
+
+        generator.emitLabel(loopStart.get());
+        generator.emitLoopHint();
+
+        RefPtr<RegisterID> result = generator.emitUnaryOp(op_eq_null, generator.newTemporary(), propertyName.get());
+        generator.emitJumpIfTrue(result.get(), loopEnd.get());
+
+        generator.emitHasGenericProperty(result.get(), base.get(), propertyName.get());
+        generator.emitJumpIfFalse(result.get(), scope->continueTarget());
+
+        this->emitLoopHeader(generator, propertyName.get());
+
+        generator.emitProfileControlFlow(profilerStartOffset);
+
+        generator.emitNode(dst, m_statement);
+
+        generator.emitLabel(scope->continueTarget());
+        generator.emitInc(enumeratorIndex.get());
+        generator.emitEnumeratorGenericPropertyName(propertyName.get(), enumerator.get(), enumeratorIndex.get());
+        generator.emitJump(loopStart.get());
+
+        generator.emitLabel(scope->breakTarget());
+        generator.emitJump(end.get());
+        generator.emitLabel(loopEnd.get());
+    }
+
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
+    generator.emitLabel(end.get());
+    generator.emitProfileControlFlow(profilerEndOffset);
+}
+
+void ForInNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    this->emitMultiLoopBytecode(generator, dst);
+}
+
+// ------------------------------ ForOfNode ------------------------------------
+void ForOfNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    if (!m_lexpr->isAssignmentLocation()) {
+        emitThrowReferenceError(generator, ASCIILiteral("Left side of for-of statement is not a reference."));
+        return;
+    }
+
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
+    auto extractor = [this, dst](BytecodeGenerator& generator, RegisterID* value)
+    {
+        if (m_lexpr->isResolveNode()) {
+            const Identifier& ident = static_cast<ResolveNode*>(m_lexpr)->identifier();
+            Variable var = generator.variable(ident);
+            if (RegisterID* local = var.local())
+                generator.emitMove(local, value);
+            else {
+                if (generator.isStrictMode())
+                    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+                RegisterID* scope = generator.emitResolveScope(nullptr, var);
+                generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
+                generator.emitPutToScope(scope, var, value, generator.isStrictMode() ? ThrowIfNotFound : DoNotThrowIfNotFound);
+                if (generator.vm()->typeProfiler())
+                    generator.emitProfileType(value, var.isResolved() ? ProfileTypeBytecodePutToLocalScope : ProfileTypeBytecodePutToScope, &ident);
+            }
+            if (generator.vm()->typeProfiler())
+                generator.emitTypeProfilerExpressionInfo(m_lexpr->position(), JSTextPosition(-1, m_lexpr->position().offset + ident.length(), -1));
+        } else if (m_lexpr->isDotAccessorNode()) {
+            DotAccessorNode* assignNode = static_cast<DotAccessorNode*>(m_lexpr);
+            const Identifier& ident = assignNode->identifier();
+            RefPtr<RegisterID> base = generator.emitNode(assignNode->base());
+            
+            generator.emitExpressionInfo(assignNode->divot(), assignNode->divotStart(), assignNode->divotEnd());
+            generator.emitPutById(base.get(), ident, value);
+            if (generator.vm()->typeProfiler()) {
+                generator.emitProfileType(value, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+                generator.emitTypeProfilerExpressionInfo(assignNode->divotStart(), assignNode->divotEnd());
+            }
+        } else if (m_lexpr->isBracketAccessorNode()) {
+            BracketAccessorNode* assignNode = static_cast<BracketAccessorNode*>(m_lexpr);
+            RefPtr<RegisterID> base = generator.emitNode(assignNode->base());
+            RegisterID* subscript = generator.emitNode(assignNode->subscript());
+            
+            generator.emitExpressionInfo(assignNode->divot(), assignNode->divotStart(), assignNode->divotEnd());
+            generator.emitPutByVal(base.get(), subscript, value);
+            if (generator.vm()->typeProfiler()) {
+                generator.emitProfileType(value, ProfileTypeBytecodeDoesNotHaveGlobalID, nullptr);
+                generator.emitTypeProfilerExpressionInfo(assignNode->divotStart(), assignNode->divotEnd());
+            }
+        } else {
+            ASSERT(m_lexpr->isDestructuringNode());
+            DestructuringAssignmentNode* assignNode = static_cast<DestructuringAssignmentNode*>(m_lexpr);
+            assignNode->bindings()->bindValue(generator, value);
+        }
+        generator.emitProfileControlFlow(m_statement->startOffset());
+        generator.emitNode(dst, m_statement);
+    };
+    generator.emitEnumeration(this, m_expr, extractor);
+    generator.emitProfileControlFlow(m_statement->endOffset() + (m_statement->isBlock() ? 1 : 0));
 }
 
 // ------------------------------ ContinueNode ---------------------------------
 
-// ECMA 12.7
-RegisterID* ContinueNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+Label* ContinueNode::trivialTarget(BytecodeGenerator& generator)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
+    if (generator.shouldEmitDebugHooks())
+        return 0;
+
+    LabelScopePtr scope = generator.continueTarget(m_ident);
+    ASSERT(scope);
+
+    if (generator.scopeDepth() != scope->scopeDepth())
+        return 0;
+
+    return scope->continueTarget();
+}
+
+void ContinueNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+{
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
     
-    LabelScope* scope = generator.continueTarget(m_ident);
+    LabelScopePtr scope = generator.continueTarget(m_ident);
+    ASSERT(scope);
 
-    if (!scope)
-        return m_ident.isEmpty()
-            ? emitThrowError(generator, SyntaxError, "Invalid continue statement.")
-            : emitThrowError(generator, SyntaxError, "Undefined label: '%s'.", m_ident);
+    generator.emitPopScopes(generator.scopeRegister(), scope->scopeDepth());
+    generator.emitJump(scope->continueTarget());
 
-    generator.emitJumpScopes(scope->continueTarget(), scope->scopeDepth());
-    return dst;
+    generator.emitProfileControlFlow(endOffset());
 }
 
 // ------------------------------ BreakNode ------------------------------------
 
-// ECMA 12.8
-RegisterID* BreakNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+Label* BreakNode::trivialTarget(BytecodeGenerator& generator)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-    
-    LabelScope* scope = generator.breakTarget(m_ident);
+    if (generator.shouldEmitDebugHooks())
+        return 0;
+
+    LabelScopePtr scope = generator.breakTarget(m_ident);
+    ASSERT(scope);
+
+    if (generator.scopeDepth() != scope->scopeDepth())
+        return 0;
+
+    return scope->breakTarget();
+}
+
+void BreakNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+{
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
     
-    if (!scope)
-        return m_ident.isEmpty()
-            ? emitThrowError(generator, SyntaxError, "Invalid break statement.")
-            : emitThrowError(generator, SyntaxError, "Undefined label: '%s'.", m_ident);
+    LabelScopePtr scope = generator.breakTarget(m_ident);
+    ASSERT(scope);
 
-    generator.emitJumpScopes(scope->breakTarget(), scope->scopeDepth());
-    return dst;
+    generator.emitPopScopes(generator.scopeRegister(), scope->scopeDepth());
+    generator.emitJump(scope->breakTarget());
+
+    generator.emitProfileControlFlow(endOffset());
 }
 
 // ------------------------------ ReturnNode -----------------------------------
 
-RegisterID* ReturnNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void ReturnNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-    if (generator.codeType() != FunctionCode)
-        return emitThrowError(generator, SyntaxError, "Invalid return statement.");
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
+    ASSERT(generator.codeType() == FunctionCode);
 
     if (dst == generator.ignoredResult())
         dst = 0;
-    RegisterID* r0 = m_value ? generator.emitNode(dst, m_value) : generator.emitLoad(dst, jsUndefined());
-    RefPtr<RegisterID> returnRegister;
+
+    RefPtr<RegisterID> returnRegister = m_value ? generator.emitNode(dst, m_value) : generator.emitLoad(dst, jsUndefined());
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(returnRegister.get(), ProfileTypeBytecodeFunctionReturnStatement, nullptr);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
     if (generator.scopeDepth()) {
-        RefPtr<Label> l0 = generator.newLabel();
-        if (generator.hasFinaliser() && !r0->isTemporary()) {
-            returnRegister = generator.emitMove(generator.newTemporary(), r0);
-            r0 = returnRegister.get();
-        }
-        generator.emitJumpScopes(l0.get(), 0);
-        generator.emitLabel(l0.get());
+        returnRegister = generator.emitMove(generator.newTemporary(), returnRegister.get());
+        generator.emitPopScopes(generator.scopeRegister(), 0);
     }
-    generator.emitDebugHook(WillLeaveCallFrame, firstLine(), lastLine());
-    return generator.emitReturn(r0);
+
+    generator.emitDebugHook(WillLeaveCallFrame, lastLine(), startOffset(), lineStartOffset());
+    generator.emitReturn(returnRegister.get());
+    generator.emitProfileControlFlow(endOffset()); 
+    // Emitting an unreachable return here is needed in case this op_profile_control_flow is the 
+    // last opcode in a CodeBlock because a CodeBlock's instructions must end with a terminal opcode.
+    if (generator.vm()->controlFlowProfiler())
+        generator.emitReturn(generator.emitLoad(nullptr, jsUndefined()));
 }
 
 // ------------------------------ WithNode -------------------------------------
 
-RegisterID* WithNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void WithNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
-    
-    RefPtr<RegisterID> scope = generator.newTemporary();
-    generator.emitNode(scope.get(), m_expr); // scope must be protected until popped
-    generator.emitExpressionInfo(m_divot, m_expressionLength, 0);
-    generator.emitPushScope(scope.get());
-    RegisterID* result = generator.emitNode(dst, m_statement);
-    generator.emitPopScope();
-    return result;
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
+
+    RefPtr<RegisterID> scope = generator.emitNode(m_expr);
+    generator.emitExpressionInfo(m_divot, m_divot - m_expressionLength, m_divot);
+    generator.emitPushWithScope(generator.scopeRegister(), scope.get());
+    generator.emitNode(dst, m_statement);
+    generator.emitPopScope(generator.scopeRegister());
 }
 
 // ------------------------------ CaseClauseNode --------------------------------
 
 inline void CaseClauseNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (m_statements)
-        m_statements->emitBytecode(generator, dst);
+    generator.emitProfileControlFlow(m_startOffset);
+    if (!m_statements)
+        return;
+    m_statements->emitBytecode(generator, dst);
 }
 
 // ------------------------------ CaseBlockNode --------------------------------
@@ -1697,9 +2690,9 @@ static void processClauseList(ClauseListNode* list, Vector<ExpressionNode*, 8>&
                 typeForTable = SwitchNeither;
                 break;
             }
-            const UString& value = static_cast<StringNode*>(clauseExpression)->value().ustring();
-            if (singleCharacterSwitch &= value.size() == 1) {
-                int32_t intVal = value.rep()->data()[0];
+            const String& value = static_cast<StringNode*>(clauseExpression)->value().string();
+            if (singleCharacterSwitch &= value.length() == 1) {
+                int32_t intVal = value[0];
                 if (intVal < min_num)
                     min_num = intVal;
                 if (intVal > max_num)
@@ -1712,9 +2705,22 @@ static void processClauseList(ClauseListNode* list, Vector<ExpressionNode*, 8>&
         break;        
     }
 }
-    
-SwitchInfo::SwitchType CaseBlockNode::tryOptimizedSwitch(Vector<ExpressionNode*, 8>& literalVector, int32_t& min_num, int32_t& max_num)
+
+static inline size_t length(ClauseListNode* list1, ClauseListNode* list2)
+{
+    size_t length = 0;
+    for (ClauseListNode* node = list1; node; node = node->getNext())
+        ++length;
+    for (ClauseListNode* node = list2; node; node = node->getNext())
+        ++length;
+    return length;
+}
+
+SwitchInfo::SwitchType CaseBlockNode::tryTableSwitch(Vector<ExpressionNode*, 8>& literalVector, int32_t& min_num, int32_t& max_num)
 {
+    if (length(m_list1, m_list2) < s_tableSwitchMinimum)
+        return SwitchInfo::SwitchNone;
+
     SwitchKind typeForTable = SwitchUnset;
     bool singleCharacterSwitch = true;
     
@@ -1742,14 +2748,14 @@ SwitchInfo::SwitchType CaseBlockNode::tryOptimizedSwitch(Vector<ExpressionNode*,
     return SwitchInfo::SwitchString;
 }
 
-RegisterID* CaseBlockNode::emitBytecodeForBlock(BytecodeGenerator& generator, RegisterID* switchExpression, RegisterID* dst)
+void CaseBlockNode::emitBytecodeForBlock(BytecodeGenerator& generator, RegisterID* switchExpression, RegisterID* dst)
 {
     RefPtr<Label> defaultLabel;
     Vector<RefPtr<Label>, 8> labelVector;
     Vector<ExpressionNode*, 8> literalVector;
     int32_t min_num = std::numeric_limits<int32_t>::max();
     int32_t max_num = std::numeric_limits<int32_t>::min();
-    SwitchInfo::SwitchType switchType = tryOptimizedSwitch(literalVector, min_num, max_num);
+    SwitchInfo::SwitchType switchType = tryTableSwitch(literalVector, min_num, max_num);
 
     if (switchType != SwitchInfo::SwitchNone) {
         // Prepare the various labels
@@ -1778,8 +2784,6 @@ RegisterID* CaseBlockNode::emitBytecodeForBlock(BytecodeGenerator& generator, Re
         generator.emitJump(defaultLabel.get());
     }
 
-    RegisterID* result = 0;
-
     size_t i = 0;
     for (ClauseListNode* list = m_list1; list; list = list->getNext()) {
         generator.emitLabel(labelVector[i++].get());
@@ -1803,73 +2807,70 @@ RegisterID* CaseBlockNode::emitBytecodeForBlock(BytecodeGenerator& generator, Re
         ASSERT(labelVector.size() == literalVector.size());
         generator.endSwitch(labelVector.size(), labelVector.data(), literalVector.data(), defaultLabel.get(), min_num, max_num);
     }
-    return result;
 }
 
 // ------------------------------ SwitchNode -----------------------------------
 
-RegisterID* SwitchNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void SwitchNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
     
-    RefPtr<LabelScope> scope = generator.newLabelScope(LabelScope::Switch);
+    LabelScopePtr scope = generator.newLabelScope(LabelScope::Switch);
 
     RefPtr<RegisterID> r0 = generator.emitNode(m_expr);
-    RegisterID* r1 = m_block->emitBytecodeForBlock(generator, r0.get(), dst);
+    m_block->emitBytecodeForBlock(generator, r0.get(), dst);
 
     generator.emitLabel(scope->breakTarget());
-    return r1;
+    generator.emitProfileControlFlow(endOffset());
 }
 
 // ------------------------------ LabelNode ------------------------------------
 
-RegisterID* LabelNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void LabelNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
 
-    if (generator.breakTarget(m_name))
-        return emitThrowError(generator, SyntaxError, "Duplicate label: %s.", m_name);
+    ASSERT(!generator.breakTarget(m_name));
 
-    RefPtr<LabelScope> scope = generator.newLabelScope(LabelScope::NamedLabel, &m_name);
-    RegisterID* r0 = generator.emitNode(dst, m_statement);
+    LabelScopePtr scope = generator.newLabelScope(LabelScope::NamedLabel, &m_name);
+    generator.emitNode(dst, m_statement);
 
     generator.emitLabel(scope->breakTarget());
-    return r0;
 }
 
 // ------------------------------ ThrowNode ------------------------------------
 
-RegisterID* ThrowNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void ThrowNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
 
     if (dst == generator.ignoredResult())
         dst = 0;
     RefPtr<RegisterID> expr = generator.emitNode(m_expr);
-    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
+    generator.emitExpressionInfo(divot(), divotStart(), divotEnd());
     generator.emitThrow(expr.get());
-    return 0;
+
+    generator.emitProfileControlFlow(endOffset()); 
 }
 
 // ------------------------------ TryNode --------------------------------------
 
-RegisterID* TryNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void TryNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
     // NOTE: The catch and finally blocks must be labeled explicitly, so the
     // optimizer knows they may be jumped to from anywhere.
 
-    generator.emitDebugHook(WillExecuteStatement, firstLine(), lastLine());
+    generator.emitDebugHook(WillExecuteStatement, firstLine(), startOffset(), lineStartOffset());
 
-    RefPtr<Label> tryStartLabel = generator.newLabel();
-    RefPtr<Label> finallyStart;
-    RefPtr<RegisterID> finallyReturnAddr;
-    if (m_finallyBlock) {
-        finallyStart = generator.newLabel();
-        finallyReturnAddr = generator.newTemporary();
-        generator.pushFinallyContext(finallyStart.get(), finallyReturnAddr.get());
-    }
+    ASSERT(m_catchBlock || m_finallyBlock);
 
+    RefPtr<Label> tryStartLabel = generator.newLabel();
     generator.emitLabel(tryStartLabel.get());
+    
+    if (m_finallyBlock)
+        generator.pushFinallyContext(m_finallyBlock);
+    TryData* tryData = generator.pushTry(tryStartLabel.get());
+
     generator.emitNode(dst, m_tryBlock);
 
     if (m_catchBlock) {
@@ -1880,113 +2881,141 @@ RegisterID* TryNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 
         // Uncaught exception path: the catch block.
         RefPtr<Label> here = generator.emitLabel(generator.newLabel().get());
-        RefPtr<RegisterID> exceptionRegister = generator.emitCatch(generator.newTemporary(), tryStartLabel.get(), here.get());
-        if (m_catchHasEval) {
-            RefPtr<RegisterID> dynamicScopeObject = generator.emitNewObject(generator.newTemporary());
-            generator.emitPutById(dynamicScopeObject.get(), m_exceptionIdent, exceptionRegister.get());
-            generator.emitMove(exceptionRegister.get(), dynamicScopeObject.get());
-            generator.emitPushScope(exceptionRegister.get());
-        } else
-            generator.emitPushNewScope(exceptionRegister.get(), m_exceptionIdent, exceptionRegister.get());
+        RefPtr<RegisterID> exceptionRegister = generator.newTemporary();
+        RefPtr<RegisterID> thrownValueRegister = generator.newTemporary();
+        generator.popTryAndEmitCatch(tryData, exceptionRegister.get(), thrownValueRegister.get(), here.get(), HandlerType::Catch);
+        
+        if (m_finallyBlock) {
+            // If the catch block throws an exception and we have a finally block, then the finally
+            // block should "catch" that exception.
+            tryData = generator.pushTry(here.get());
+        }
+
+        generator.emitPushCatchScope(generator.scopeRegister(), m_thrownValueIdent, thrownValueRegister.get(), DontDelete);
+        generator.emitProfileControlFlow(m_tryBlock->endOffset() + 1);
         generator.emitNode(dst, m_catchBlock);
-        generator.emitPopScope();
+        generator.emitPopScope(generator.scopeRegister());
         generator.emitLabel(catchEndLabel.get());
     }
 
     if (m_finallyBlock) {
+        RefPtr<Label> preFinallyLabel = generator.emitLabel(generator.newLabel().get());
+        
         generator.popFinallyContext();
-        // there may be important registers live at the time we jump
-        // to a finally block (such as for a return or throw) so we
-        // ref the highest register ever used as a conservative
-        // approach to not clobbering anything important
-        RefPtr<RegisterID> highestUsedRegister = generator.highestUsedRegister();
+
         RefPtr<Label> finallyEndLabel = generator.newLabel();
 
-        // Normal path: invoke the finally block, then jump over it.
-        generator.emitJumpSubroutine(finallyReturnAddr.get(), finallyStart.get());
+        int finallyStartOffset = m_catchBlock ? m_catchBlock->endOffset() + 1 : m_tryBlock->endOffset() + 1;
+
+        // Normal path: run the finally code, and jump to the end.
+        generator.emitProfileControlFlow(finallyStartOffset);
+        generator.emitNode(dst, m_finallyBlock);
+        generator.emitProfileControlFlow(m_finallyBlock->endOffset() + 1);
         generator.emitJump(finallyEndLabel.get());
 
         // Uncaught exception path: invoke the finally block, then re-throw the exception.
-        RefPtr<Label> here = generator.emitLabel(generator.newLabel().get());
-        RefPtr<RegisterID> tempExceptionRegister = generator.emitCatch(generator.newTemporary(), tryStartLabel.get(), here.get());
-        generator.emitJumpSubroutine(finallyReturnAddr.get(), finallyStart.get());
-        generator.emitThrow(tempExceptionRegister.get());
-
-        // The finally block.
-        generator.emitLabel(finallyStart.get());
+        RefPtr<RegisterID> exceptionRegister = generator.newTemporary();
+        RefPtr<RegisterID> thrownValueRegister = generator.newTemporary();
+        generator.popTryAndEmitCatch(tryData, exceptionRegister.get(), thrownValueRegister.get(), preFinallyLabel.get(), HandlerType::Finally);
+        generator.emitProfileControlFlow(finallyStartOffset);
         generator.emitNode(dst, m_finallyBlock);
-        generator.emitSubroutineReturn(finallyReturnAddr.get());
+        generator.emitThrow(exceptionRegister.get());
 
         generator.emitLabel(finallyEndLabel.get());
-    }
+        generator.emitProfileControlFlow(m_finallyBlock->endOffset() + 1);
+    } else
+        generator.emitProfileControlFlow(m_catchBlock->endOffset() + 1);
 
-    return dst;
 }
 
 // ------------------------------ ScopeNode -----------------------------
 
 inline void ScopeNode::emitStatementsBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (m_data->m_statements)
-        m_data->m_statements->emitBytecode(generator, dst);
+    if (!m_statements)
+        return;
+    m_statements->emitBytecode(generator, dst);
 }
 
 // ------------------------------ ProgramNode -----------------------------
 
-RegisterID* ProgramNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+void ProgramNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
 {
-    generator.emitDebugHook(WillExecuteProgram, firstLine(), lastLine());
+    generator.emitDebugHook(WillExecuteProgram, startLine(), startStartOffset(), startLineStartOffset());
 
     RefPtr<RegisterID> dstRegister = generator.newTemporary();
     generator.emitLoad(dstRegister.get(), jsUndefined());
+    generator.emitProfileControlFlow(startStartOffset());
     emitStatementsBytecode(generator, dstRegister.get());
 
-    generator.emitDebugHook(DidExecuteProgram, firstLine(), lastLine());
+    generator.emitDebugHook(DidExecuteProgram, lastLine(), startOffset(), lineStartOffset());
     generator.emitEnd(dstRegister.get());
-    return 0;
 }
 
 // ------------------------------ EvalNode -----------------------------
 
-RegisterID* EvalNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+void EvalNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
 {
-    generator.emitDebugHook(WillExecuteProgram, firstLine(), lastLine());
+    generator.emitDebugHook(WillExecuteProgram, startLine(), startStartOffset(), startLineStartOffset());
 
     RefPtr<RegisterID> dstRegister = generator.newTemporary();
     generator.emitLoad(dstRegister.get(), jsUndefined());
     emitStatementsBytecode(generator, dstRegister.get());
 
-    generator.emitDebugHook(DidExecuteProgram, firstLine(), lastLine());
+    generator.emitDebugHook(DidExecuteProgram, lastLine(), startOffset(), lineStartOffset());
     generator.emitEnd(dstRegister.get());
-    return 0;
 }
 
 // ------------------------------ FunctionBodyNode -----------------------------
 
-RegisterID* FunctionBodyNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+void FunctionBodyNode::emitBytecode(BytecodeGenerator&, RegisterID*)
 {
-    generator.emitDebugHook(DidEnterCallFrame, firstLine(), lastLine());
+}
+
+void FunctionNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
+{
+    if (generator.vm()->typeProfiler()) {
+        for (size_t i = 0; i < m_parameters->size(); i++) {
+            // FIXME: Handle Destructuring assignments into arguments.
+            if (!m_parameters->at(i)->isBindingNode())
+                continue;
+            BindingNode* parameter = static_cast<BindingNode*>(m_parameters->at(i));
+            RegisterID reg(CallFrame::argumentOffset(i));
+            generator.emitProfileType(&reg, ProfileTypeBytecodeFunctionArgument, nullptr);
+            generator.emitTypeProfilerExpressionInfo(parameter->divotStart(), parameter->divotEnd());
+        }
+    }
+
+    generator.emitProfileControlFlow(startStartOffset());
+    generator.emitDebugHook(DidEnterCallFrame, startLine(), startStartOffset(), startLineStartOffset());
     emitStatementsBytecode(generator, generator.ignoredResult());
+
     StatementNode* singleStatement = this->singleStatement();
+    ReturnNode* returnNode = 0;
+
+    // Check for a return statement at the end of a function composed of a single block.
     if (singleStatement && singleStatement->isBlock()) {
         StatementNode* lastStatementInBlock = static_cast<BlockNode*>(singleStatement)->lastStatement();
         if (lastStatementInBlock && lastStatementInBlock->isReturnNode())
-            return 0;
+            returnNode = static_cast<ReturnNode*>(lastStatementInBlock);
     }
 
-    RegisterID* r0 = generator.emitLoad(0, jsUndefined());
-    generator.emitDebugHook(WillLeaveCallFrame, firstLine(), lastLine());
-    generator.emitReturn(r0);
-    return 0;
+    // If there is no return we must automatically insert one.
+    if (!returnNode) {
+        RegisterID* r0 = generator.isConstructor() ? generator.thisRegister() : generator.emitLoad(0, jsUndefined());
+        if (generator.vm()->typeProfiler())
+            generator.emitProfileType(r0, ProfileTypeBytecodeFunctionReturnStatement, nullptr); // Do not emit expression info for this profile because it's not in the user's source code.
+        ASSERT(startOffset() >= lineStartOffset());
+        generator.emitDebugHook(WillLeaveCallFrame, lastLine(), startOffset(), lineStartOffset());
+        generator.emitReturn(r0);
+        return;
+    }
 }
 
 // ------------------------------ FuncDeclNode ---------------------------------
 
-RegisterID* FuncDeclNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+void FuncDeclNode::emitBytecode(BytecodeGenerator&, RegisterID*)
 {
-    if (dst == generator.ignoredResult())
-        dst = 0;
-    return dst;
 }
 
 // ------------------------------ FuncExprNode ---------------------------------
@@ -1996,4 +3025,336 @@ RegisterID* FuncExprNode::emitBytecode(BytecodeGenerator& generator, RegisterID*
     return generator.emitNewFunctionExpression(generator.finalDestination(dst), this);
 }
 
+#if ENABLE(ES6_CLASS_SYNTAX)
+// ------------------------------ ClassDeclNode ---------------------------------
+
+void ClassDeclNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    generator.emitNode(dst, m_classDeclaration);
+}
+
+// ------------------------------ ClassExprNode ---------------------------------
+
+RegisterID* ClassExprNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    RefPtr<RegisterID> superclass;
+    if (m_classHeritage) {
+        superclass = generator.newTemporary();
+        generator.emitNode(superclass.get(), m_classHeritage);
+    }
+
+    RefPtr<RegisterID> constructor;
+
+    // FIXME: Make the prototype non-configurable & non-writable.
+    if (m_constructorExpression)
+        constructor = generator.emitNode(dst, m_constructorExpression);
+    else {
+        constructor = generator.emitNewDefaultConstructor(generator.finalDestination(dst),
+            m_classHeritage ? ConstructorKind::Derived : ConstructorKind::Base, m_name);
+    }
+
+    const auto& propertyNames = generator.propertyNames();
+    RefPtr<RegisterID> prototype = generator.emitNewObject(generator.newTemporary());
+
+    if (superclass) {
+        RefPtr<RegisterID> protoParent = generator.newTemporary();
+        generator.emitLoad(protoParent.get(), jsNull());
+
+        RefPtr<RegisterID> tempRegister = generator.newTemporary();
+
+        // FIXME: Throw TypeError if it's a generator function.
+        RefPtr<Label> superclassIsUndefinedLabel = generator.newLabel();
+        generator.emitJumpIfTrue(generator.emitIsUndefined(tempRegister.get(), superclass.get()), superclassIsUndefinedLabel.get());
+
+        RefPtr<Label> superclassIsNullLabel = generator.newLabel();
+        generator.emitJumpIfTrue(generator.emitUnaryOp(op_eq_null, tempRegister.get(), superclass.get()), superclassIsNullLabel.get());
+
+        RefPtr<Label> superclassIsObjectLabel = generator.newLabel();
+        generator.emitJumpIfTrue(generator.emitIsObject(tempRegister.get(), superclass.get()), superclassIsObjectLabel.get());
+        generator.emitLabel(superclassIsUndefinedLabel.get());
+        generator.emitThrowTypeError(ASCIILiteral("The superclass is not an object."));
+        generator.emitLabel(superclassIsObjectLabel.get());
+        generator.emitGetById(protoParent.get(), superclass.get(), generator.propertyNames().prototype);
+
+        RefPtr<Label> protoParentIsObjectOrNullLabel = generator.newLabel();
+        generator.emitJumpIfTrue(generator.emitUnaryOp(op_is_object_or_null, tempRegister.get(), protoParent.get()), protoParentIsObjectOrNullLabel.get());
+        generator.emitThrowTypeError(ASCIILiteral("The superclass's prototype is not an object."));
+        generator.emitLabel(protoParentIsObjectOrNullLabel.get());
+
+        generator.emitDirectPutById(constructor.get(), generator.propertyNames().underscoreProto, superclass.get(), PropertyNode::Unknown);
+        generator.emitLabel(superclassIsNullLabel.get());
+        generator.emitDirectPutById(prototype.get(), generator.propertyNames().underscoreProto, protoParent.get(), PropertyNode::Unknown);
+
+        emitPutHomeObject(generator, constructor.get(), prototype.get());
+    }
+
+    RefPtr<RegisterID> constructorNameRegister = generator.emitLoad(generator.newTemporary(), propertyNames.constructor);
+    generator.emitCallDefineProperty(prototype.get(), constructorNameRegister.get(), constructor.get(), nullptr, nullptr,
+        BytecodeGenerator::PropertyConfigurable | BytecodeGenerator::PropertyWritable, m_position);
+
+    RefPtr<RegisterID> prototypeNameRegister = generator.emitLoad(generator.newTemporary(), propertyNames.prototype);
+    generator.emitCallDefineProperty(constructor.get(), prototypeNameRegister.get(), prototype.get(), nullptr, nullptr, 0, m_position);
+
+    if (m_staticMethods)
+        generator.emitNode(constructor.get(), m_staticMethods);
+
+    if (m_instanceMethods)
+        generator.emitNode(prototype.get(), m_instanceMethods);
+
+    return generator.moveToDestinationIfNeeded(dst, constructor.get());
+}
+#endif
+    
+// ------------------------------ DestructuringAssignmentNode -----------------
+RegisterID* DestructuringAssignmentNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    if (RegisterID* result = m_bindings->emitDirectBinding(generator, dst, m_initializer))
+        return result;
+    RefPtr<RegisterID> initializer = generator.tempDestination(dst);
+    generator.emitNode(initializer.get(), m_initializer);
+    m_bindings->bindValue(generator, initializer.get());
+    return generator.moveToDestinationIfNeeded(dst, initializer.get());
+}
+
+DestructuringPatternNode::~DestructuringPatternNode()
+{
+}
+
+static void assignDefaultValueIfUndefined(BytecodeGenerator& generator, RegisterID* maybeUndefined, ExpressionNode* defaultValue)
+{
+    ASSERT(defaultValue);
+    RefPtr<Label> isNotUndefined = generator.newLabel();
+    generator.emitJumpIfFalse(generator.emitIsUndefined(generator.newTemporary(), maybeUndefined), isNotUndefined.get());
+    generator.emitNode(maybeUndefined, defaultValue);
+    generator.emitLabel(isNotUndefined.get());
+}
+
+void ArrayPatternNode::bindValue(BytecodeGenerator& generator, RegisterID* rhs) const
+{
+    RefPtr<RegisterID> iterator = generator.newTemporary();
+    {
+        generator.emitGetById(iterator.get(), rhs, generator.propertyNames().iteratorSymbol);
+        CallArguments args(generator, nullptr);
+        generator.emitMove(args.thisRegister(), rhs);
+        generator.emitCall(iterator.get(), iterator.get(), NoExpectedFunction, args, divot(), divotStart(), divotEnd());
+    }
+
+    if (m_targetPatterns.isEmpty()) {
+        generator.emitIteratorClose(iterator.get(), this);
+        return;
+    }
+
+    RefPtr<RegisterID> done;
+    for (auto& target : m_targetPatterns) {
+        switch (target.bindingType) {
+        case BindingType::Elision:
+        case BindingType::Element: {
+            RefPtr<Label> iterationSkipped = generator.newLabel();
+            if (!done)
+                done = generator.newTemporary();
+            else
+                generator.emitJumpIfTrue(done.get(), iterationSkipped.get());
+
+            RefPtr<RegisterID> value = generator.newTemporary();
+            generator.emitIteratorNext(value.get(), iterator.get(), this);
+            generator.emitGetById(done.get(), value.get(), generator.propertyNames().done);
+            generator.emitJumpIfTrue(done.get(), iterationSkipped.get());
+            generator.emitGetById(value.get(), value.get(), generator.propertyNames().value);
+
+            {
+                RefPtr<Label> valueIsSet = generator.newLabel();
+                generator.emitJump(valueIsSet.get());
+                generator.emitLabel(iterationSkipped.get());
+                generator.emitLoad(value.get(), jsUndefined());
+                generator.emitLabel(valueIsSet.get());
+            }
+
+            if (target.bindingType == BindingType::Element) {
+                if (target.defaultValue)
+                    assignDefaultValueIfUndefined(generator, value.get(), target.defaultValue);
+                target.pattern->bindValue(generator, value.get());
+            }
+            break;
+        }
+
+        case BindingType::RestElement: {
+            RefPtr<RegisterID> array = generator.emitNewArray(generator.newTemporary(), 0, 0);
+
+            RefPtr<Label> iterationDone = generator.newLabel();
+            if (!done)
+                done = generator.newTemporary();
+            else
+                generator.emitJumpIfTrue(done.get(), iterationDone.get());
+
+            RefPtr<RegisterID> index = generator.newTemporary();
+            generator.emitLoad(index.get(), jsNumber(0));
+            RefPtr<Label> loopStart = generator.newLabel();
+            generator.emitLabel(loopStart.get());
+
+            RefPtr<RegisterID> value = generator.newTemporary();
+            generator.emitIteratorNext(value.get(), iterator.get(), this);
+            generator.emitGetById(done.get(), value.get(), generator.propertyNames().done);
+            generator.emitJumpIfTrue(done.get(), iterationDone.get());
+            generator.emitGetById(value.get(), value.get(), generator.propertyNames().value);
+
+            generator.emitDirectPutByVal(array.get(), index.get(), value.get());
+            generator.emitInc(index.get());
+            generator.emitJump(loopStart.get());
+
+            generator.emitLabel(iterationDone.get());
+            target.pattern->bindValue(generator, array.get());
+            break;
+        }
+        }
+    }
+
+    RefPtr<Label> iteratorClosed = generator.newLabel();
+    generator.emitJumpIfTrue(done.get(), iteratorClosed.get());
+    generator.emitIteratorClose(iterator.get(), this);
+    generator.emitLabel(iteratorClosed.get());
+}
+
+RegisterID* ArrayPatternNode::emitDirectBinding(BytecodeGenerator& generator, RegisterID* dst, ExpressionNode* rhs)
+{
+    if (!rhs->isSimpleArray())
+        return 0;
+
+    RefPtr<RegisterID> resultRegister;
+    if (dst && dst != generator.ignoredResult())
+        resultRegister = generator.emitNewArray(generator.newTemporary(), 0, 0);
+    ElementNode* elementNodes = static_cast<ArrayNode*>(rhs)->elements();
+    Vector<ExpressionNode*> elements;
+    for (; elementNodes; elementNodes = elementNodes->next())
+        elements.append(elementNodes->value());
+    if (m_targetPatterns.size() != elements.size())
+        return 0;
+    Vector<RefPtr<RegisterID>> registers;
+    registers.reserveCapacity(m_targetPatterns.size());
+    for (size_t i = 0; i < m_targetPatterns.size(); i++) {
+        registers.uncheckedAppend(generator.newTemporary());
+        generator.emitNode(registers.last().get(), elements[i]);
+        if (m_targetPatterns[i].defaultValue)
+            assignDefaultValueIfUndefined(generator, registers.last().get(), m_targetPatterns[i].defaultValue);
+        if (resultRegister)
+            generator.emitPutByIndex(resultRegister.get(), i, registers.last().get());
+    }
+    
+    for (size_t i = 0; i < m_targetPatterns.size(); i++) {
+        if (m_targetPatterns[i].pattern)
+            m_targetPatterns[i].pattern->bindValue(generator, registers[i].get());
+    }
+    if (resultRegister)
+        return generator.moveToDestinationIfNeeded(dst, resultRegister.get());
+    return generator.emitLoad(generator.finalDestination(dst), jsUndefined());
+}
+
+void ArrayPatternNode::toString(StringBuilder& builder) const
+{
+    builder.append('[');
+    for (size_t i = 0; i < m_targetPatterns.size(); i++) {
+        const auto& target = m_targetPatterns[i];
+
+        switch (target.bindingType) {
+        case BindingType::Elision:
+            builder.append(',');
+            break;
+
+        case BindingType::Element:
+            target.pattern->toString(builder);
+            if (i < m_targetPatterns.size() - 1)
+                builder.append(',');
+            break;
+
+        case BindingType::RestElement:
+            builder.append("...");
+            target.pattern->toString(builder);
+            break;
+        }
+    }
+    builder.append(']');
+}
+
+void ArrayPatternNode::collectBoundIdentifiers(Vector<Identifier>& identifiers) const
+{
+    for (size_t i = 0; i < m_targetPatterns.size(); i++) {
+        if (DestructuringPatternNode* node = m_targetPatterns[i].pattern.get())
+            node->collectBoundIdentifiers(identifiers);
+    }
+}
+
+void ObjectPatternNode::toString(StringBuilder& builder) const
+{
+    builder.append('{');
+    for (size_t i = 0; i < m_targetPatterns.size(); i++) {
+        if (m_targetPatterns[i].wasString)
+            builder.appendQuotedJSONString(m_targetPatterns[i].propertyName.string());
+        else
+            builder.append(m_targetPatterns[i].propertyName.string());
+        builder.append(':');
+        m_targetPatterns[i].pattern->toString(builder);
+        if (i < m_targetPatterns.size() - 1)
+            builder.append(',');
+    }
+    builder.append('}');
+}
+    
+void ObjectPatternNode::bindValue(BytecodeGenerator& generator, RegisterID* rhs) const
+{
+    for (size_t i = 0; i < m_targetPatterns.size(); i++) {
+        auto& target = m_targetPatterns[i];
+        RefPtr<RegisterID> temp = generator.newTemporary();
+        generator.emitGetById(temp.get(), rhs, target.propertyName);
+        if (target.defaultValue)
+            assignDefaultValueIfUndefined(generator, temp.get(), target.defaultValue);
+        target.pattern->bindValue(generator, temp.get());
+    }
+}
+
+void ObjectPatternNode::collectBoundIdentifiers(Vector<Identifier>& identifiers) const
+{
+    for (size_t i = 0; i < m_targetPatterns.size(); i++)
+        m_targetPatterns[i].pattern->collectBoundIdentifiers(identifiers);
+}
+
+void BindingNode::bindValue(BytecodeGenerator& generator, RegisterID* value) const
+{
+    Variable var = generator.variable(m_boundProperty);
+    if (RegisterID* local = var.local()) {
+        if (var.isReadOnly()) {
+            generator.emitReadOnlyExceptionIfNeeded();
+            return;
+        }
+        generator.emitMove(local, value);
+        if (generator.vm()->typeProfiler())
+            generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+        return;
+    }
+    if (generator.isStrictMode())
+        generator.emitExpressionInfo(divotEnd(), divotStart(), divotEnd());
+    RegisterID* scope = generator.emitResolveScope(nullptr, var);
+    generator.emitExpressionInfo(divotEnd(), divotStart(), divotEnd());
+    generator.emitPutToScope(scope, var, value, generator.isStrictMode() ? ThrowIfNotFound : DoNotThrowIfNotFound);
+    if (generator.vm()->typeProfiler()) {
+        generator.emitProfileType(value, var.isResolved() ? ProfileTypeBytecodePutToLocalScope : ProfileTypeBytecodePutToScope, &m_boundProperty);
+        generator.emitTypeProfilerExpressionInfo(divotStart(), divotEnd());
+    }
+    return;
+}
+
+void BindingNode::toString(StringBuilder& builder) const
+{
+    builder.append(m_boundProperty.string());
+}
+
+void BindingNode::collectBoundIdentifiers(Vector<Identifier>& identifiers) const
+{
+    identifiers.append(m_boundProperty);
+}
+    
+RegisterID* SpreadExpressionNode::emitBytecode(BytecodeGenerator&, RegisterID*)
+{
+    RELEASE_ASSERT_NOT_REACHED();
+    return 0;
+}
+
 } // namespace JSC