Move V8 to external/v8

Change-Id: If68025d67453785a651c5dfb34fad298c16676a4
diff --git a/src/ia32/codegen-ia32.cc b/src/ia32/codegen-ia32.cc
new file mode 100644
index 0000000..0e314b9
--- /dev/null
+++ b/src/ia32/codegen-ia32.cc
@@ -0,0 +1,7979 @@
+// Copyright 2006-2009 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "v8.h"
+
+#include "bootstrapper.h"
+#include "codegen-inl.h"
+#include "debug.h"
+#include "ic-inl.h"
+#include "parser.h"
+#include "register-allocator-inl.h"
+#include "runtime.h"
+#include "scopes.h"
+
+namespace v8 {
+namespace internal {
+
+#define __ ACCESS_MASM(masm_)
+
+// -------------------------------------------------------------------------
+// Platform-specific DeferredCode functions.
+
+void DeferredCode::SaveRegisters() {
+  for (int i = 0; i < RegisterAllocator::kNumRegisters; i++) {
+    int action = registers_[i];
+    if (action == kPush) {
+      __ push(RegisterAllocator::ToRegister(i));
+    } else if (action != kIgnore && (action & kSyncedFlag) == 0) {
+      __ mov(Operand(ebp, action), RegisterAllocator::ToRegister(i));
+    }
+  }
+}
+
+
+void DeferredCode::RestoreRegisters() {
+  // Restore registers in reverse order due to the stack.
+  for (int i = RegisterAllocator::kNumRegisters - 1; i >= 0; i--) {
+    int action = registers_[i];
+    if (action == kPush) {
+      __ pop(RegisterAllocator::ToRegister(i));
+    } else if (action != kIgnore) {
+      action &= ~kSyncedFlag;
+      __ mov(RegisterAllocator::ToRegister(i), Operand(ebp, action));
+    }
+  }
+}
+
+
+// -------------------------------------------------------------------------
+// CodeGenState implementation.
+
+CodeGenState::CodeGenState(CodeGenerator* owner)
+    : owner_(owner),
+      typeof_state_(NOT_INSIDE_TYPEOF),
+      destination_(NULL),
+      previous_(NULL) {
+  owner_->set_state(this);
+}
+
+
+CodeGenState::CodeGenState(CodeGenerator* owner,
+                           TypeofState typeof_state,
+                           ControlDestination* destination)
+    : owner_(owner),
+      typeof_state_(typeof_state),
+      destination_(destination),
+      previous_(owner->state()) {
+  owner_->set_state(this);
+}
+
+
+CodeGenState::~CodeGenState() {
+  ASSERT(owner_->state() == this);
+  owner_->set_state(previous_);
+}
+
+
+// -------------------------------------------------------------------------
+// CodeGenerator implementation
+
+CodeGenerator::CodeGenerator(int buffer_size,
+                             Handle<Script> script,
+                             bool is_eval)
+    : is_eval_(is_eval),
+      script_(script),
+      deferred_(8),
+      masm_(new MacroAssembler(NULL, buffer_size)),
+      scope_(NULL),
+      frame_(NULL),
+      allocator_(NULL),
+      state_(NULL),
+      loop_nesting_(0),
+      function_return_is_shadowed_(false),
+      in_spilled_code_(false) {
+}
+
+
+// Calling conventions:
+// ebp: caller's frame pointer
+// esp: stack pointer
+// edi: called JS function
+// esi: callee's context
+
+void CodeGenerator::GenCode(FunctionLiteral* fun) {
+  // Record the position for debugging purposes.
+  CodeForFunctionPosition(fun);
+
+  ZoneList<Statement*>* body = fun->body();
+
+  // Initialize state.
+  ASSERT(scope_ == NULL);
+  scope_ = fun->scope();
+  ASSERT(allocator_ == NULL);
+  RegisterAllocator register_allocator(this);
+  allocator_ = &register_allocator;
+  ASSERT(frame_ == NULL);
+  frame_ = new VirtualFrame();
+  set_in_spilled_code(false);
+
+  // Adjust for function-level loop nesting.
+  loop_nesting_ += fun->loop_nesting();
+
+  JumpTarget::set_compiling_deferred_code(false);
+
+#ifdef DEBUG
+  if (strlen(FLAG_stop_at) > 0 &&
+      fun->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
+    frame_->SpillAll();
+    __ int3();
+  }
+#endif
+
+  // New scope to get automatic timing calculation.
+  {  // NOLINT
+    HistogramTimerScope codegen_timer(&Counters::code_generation);
+    CodeGenState state(this);
+
+    // Entry:
+    // Stack: receiver, arguments, return address.
+    // ebp: caller's frame pointer
+    // esp: stack pointer
+    // edi: called JS function
+    // esi: callee's context
+    allocator_->Initialize();
+    frame_->Enter();
+
+    // Allocate space for locals and initialize them.
+    frame_->AllocateStackSlots();
+    // Initialize the function return target after the locals are set
+    // up, because it needs the expected frame height from the frame.
+    function_return_.set_direction(JumpTarget::BIDIRECTIONAL);
+    function_return_is_shadowed_ = false;
+
+    // Allocate the local context if needed.
+    if (scope_->num_heap_slots() > 0) {
+      Comment cmnt(masm_, "[ allocate local context");
+      // Allocate local context.
+      // Get outer context and create a new context based on it.
+      frame_->PushFunction();
+      Result context = frame_->CallRuntime(Runtime::kNewContext, 1);
+
+      // Update context local.
+      frame_->SaveContextRegister();
+
+      // Verify that the runtime call result and esi agree.
+      if (FLAG_debug_code) {
+        __ cmp(context.reg(), Operand(esi));
+        __ Assert(equal, "Runtime::NewContext should end up in esi");
+      }
+    }
+
+    // TODO(1241774): Improve this code:
+    // 1) only needed if we have a context
+    // 2) no need to recompute context ptr every single time
+    // 3) don't copy parameter operand code from SlotOperand!
+    {
+      Comment cmnt2(masm_, "[ copy context parameters into .context");
+
+      // Note that iteration order is relevant here! If we have the same
+      // parameter twice (e.g., function (x, y, x)), and that parameter
+      // needs to be copied into the context, it must be the last argument
+      // passed to the parameter that needs to be copied. This is a rare
+      // case so we don't check for it, instead we rely on the copying
+      // order: such a parameter is copied repeatedly into the same
+      // context location and thus the last value is what is seen inside
+      // the function.
+      for (int i = 0; i < scope_->num_parameters(); i++) {
+        Variable* par = scope_->parameter(i);
+        Slot* slot = par->slot();
+        if (slot != NULL && slot->type() == Slot::CONTEXT) {
+          // The use of SlotOperand below is safe in unspilled code
+          // because the slot is guaranteed to be a context slot.
+          //
+          // There are no parameters in the global scope.
+          ASSERT(!scope_->is_global_scope());
+          frame_->PushParameterAt(i);
+          Result value = frame_->Pop();
+          value.ToRegister();
+
+          // SlotOperand loads context.reg() with the context object
+          // stored to, used below in RecordWrite.
+          Result context = allocator_->Allocate();
+          ASSERT(context.is_valid());
+          __ mov(SlotOperand(slot, context.reg()), value.reg());
+          int offset = FixedArray::kHeaderSize + slot->index() * kPointerSize;
+          Result scratch = allocator_->Allocate();
+          ASSERT(scratch.is_valid());
+          frame_->Spill(context.reg());
+          frame_->Spill(value.reg());
+          __ RecordWrite(context.reg(), offset, value.reg(), scratch.reg());
+        }
+      }
+    }
+
+    // Store the arguments object.  This must happen after context
+    // initialization because the arguments object may be stored in
+    // the context.
+    if (ArgumentsMode() != NO_ARGUMENTS_ALLOCATION) {
+      StoreArgumentsObject(true);
+    }
+
+    // Generate code to 'execute' declarations and initialize functions
+    // (source elements). In case of an illegal redeclaration we need to
+    // handle that instead of processing the declarations.
+    if (scope_->HasIllegalRedeclaration()) {
+      Comment cmnt(masm_, "[ illegal redeclarations");
+      scope_->VisitIllegalRedeclaration(this);
+    } else {
+      Comment cmnt(masm_, "[ declarations");
+      ProcessDeclarations(scope_->declarations());
+      // Bail out if a stack-overflow exception occurred when processing
+      // declarations.
+      if (HasStackOverflow()) return;
+    }
+
+    if (FLAG_trace) {
+      frame_->CallRuntime(Runtime::kTraceEnter, 0);
+      // Ignore the return value.
+    }
+    CheckStack();
+
+    // Compile the body of the function in a vanilla state. Don't
+    // bother compiling all the code if the scope has an illegal
+    // redeclaration.
+    if (!scope_->HasIllegalRedeclaration()) {
+      Comment cmnt(masm_, "[ function body");
+#ifdef DEBUG
+      bool is_builtin = Bootstrapper::IsActive();
+      bool should_trace =
+          is_builtin ? FLAG_trace_builtin_calls : FLAG_trace_calls;
+      if (should_trace) {
+        frame_->CallRuntime(Runtime::kDebugTrace, 0);
+        // Ignore the return value.
+      }
+#endif
+      VisitStatements(body);
+
+      // Handle the return from the function.
+      if (has_valid_frame()) {
+        // If there is a valid frame, control flow can fall off the end of
+        // the body.  In that case there is an implicit return statement.
+        ASSERT(!function_return_is_shadowed_);
+        CodeForReturnPosition(fun);
+        frame_->PrepareForReturn();
+        Result undefined(Factory::undefined_value());
+        if (function_return_.is_bound()) {
+          function_return_.Jump(&undefined);
+        } else {
+          function_return_.Bind(&undefined);
+          GenerateReturnSequence(&undefined);
+        }
+      } else if (function_return_.is_linked()) {
+        // If the return target has dangling jumps to it, then we have not
+        // yet generated the return sequence.  This can happen when (a)
+        // control does not flow off the end of the body so we did not
+        // compile an artificial return statement just above, and (b) there
+        // are return statements in the body but (c) they are all shadowed.
+        Result return_value;
+        function_return_.Bind(&return_value);
+        GenerateReturnSequence(&return_value);
+      }
+    }
+  }
+
+  // Adjust for function-level loop nesting.
+  loop_nesting_ -= fun->loop_nesting();
+
+  // Code generation state must be reset.
+  ASSERT(state_ == NULL);
+  ASSERT(loop_nesting() == 0);
+  ASSERT(!function_return_is_shadowed_);
+  function_return_.Unuse();
+  DeleteFrame();
+
+  // Process any deferred code using the register allocator.
+  if (!HasStackOverflow()) {
+    HistogramTimerScope deferred_timer(&Counters::deferred_code_generation);
+    JumpTarget::set_compiling_deferred_code(true);
+    ProcessDeferred();
+    JumpTarget::set_compiling_deferred_code(false);
+  }
+
+  // There is no need to delete the register allocator, it is a
+  // stack-allocated local.
+  allocator_ = NULL;
+  scope_ = NULL;
+}
+
+
+Operand CodeGenerator::SlotOperand(Slot* slot, Register tmp) {
+  // Currently, this assertion will fail if we try to assign to
+  // a constant variable that is constant because it is read-only
+  // (such as the variable referring to a named function expression).
+  // We need to implement assignments to read-only variables.
+  // Ideally, we should do this during AST generation (by converting
+  // such assignments into expression statements); however, in general
+  // we may not be able to make the decision until past AST generation,
+  // that is when the entire program is known.
+  ASSERT(slot != NULL);
+  int index = slot->index();
+  switch (slot->type()) {
+    case Slot::PARAMETER:
+      return frame_->ParameterAt(index);
+
+    case Slot::LOCAL:
+      return frame_->LocalAt(index);
+
+    case Slot::CONTEXT: {
+      // Follow the context chain if necessary.
+      ASSERT(!tmp.is(esi));  // do not overwrite context register
+      Register context = esi;
+      int chain_length = scope()->ContextChainLength(slot->var()->scope());
+      for (int i = 0; i < chain_length; i++) {
+        // Load the closure.
+        // (All contexts, even 'with' contexts, have a closure,
+        // and it is the same for all contexts inside a function.
+        // There is no need to go to the function context first.)
+        __ mov(tmp, ContextOperand(context, Context::CLOSURE_INDEX));
+        // Load the function context (which is the incoming, outer context).
+        __ mov(tmp, FieldOperand(tmp, JSFunction::kContextOffset));
+        context = tmp;
+      }
+      // We may have a 'with' context now. Get the function context.
+      // (In fact this mov may never be the needed, since the scope analysis
+      // may not permit a direct context access in this case and thus we are
+      // always at a function context. However it is safe to dereference be-
+      // cause the function context of a function context is itself. Before
+      // deleting this mov we should try to create a counter-example first,
+      // though...)
+      __ mov(tmp, ContextOperand(context, Context::FCONTEXT_INDEX));
+      return ContextOperand(tmp, index);
+    }
+
+    default:
+      UNREACHABLE();
+      return Operand(eax);
+  }
+}
+
+
+Operand CodeGenerator::ContextSlotOperandCheckExtensions(Slot* slot,
+                                                         Result tmp,
+                                                         JumpTarget* slow) {
+  ASSERT(slot->type() == Slot::CONTEXT);
+  ASSERT(tmp.is_register());
+  Register context = esi;
+
+  for (Scope* s = scope(); s != slot->var()->scope(); s = s->outer_scope()) {
+    if (s->num_heap_slots() > 0) {
+      if (s->calls_eval()) {
+        // Check that extension is NULL.
+        __ cmp(ContextOperand(context, Context::EXTENSION_INDEX),
+               Immediate(0));
+        slow->Branch(not_equal, not_taken);
+      }
+      __ mov(tmp.reg(), ContextOperand(context, Context::CLOSURE_INDEX));
+      __ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
+      context = tmp.reg();
+    }
+  }
+  // Check that last extension is NULL.
+  __ cmp(ContextOperand(context, Context::EXTENSION_INDEX), Immediate(0));
+  slow->Branch(not_equal, not_taken);
+  __ mov(tmp.reg(), ContextOperand(context, Context::FCONTEXT_INDEX));
+  return ContextOperand(tmp.reg(), slot->index());
+}
+
+
+// Emit code to load the value of an expression to the top of the
+// frame. If the expression is boolean-valued it may be compiled (or
+// partially compiled) into control flow to the control destination.
+// If force_control is true, control flow is forced.
+void CodeGenerator::LoadCondition(Expression* x,
+                                  TypeofState typeof_state,
+                                  ControlDestination* dest,
+                                  bool force_control) {
+  ASSERT(!in_spilled_code());
+  int original_height = frame_->height();
+
+  { CodeGenState new_state(this, typeof_state, dest);
+    Visit(x);
+
+    // If we hit a stack overflow, we may not have actually visited
+    // the expression.  In that case, we ensure that we have a
+    // valid-looking frame state because we will continue to generate
+    // code as we unwind the C++ stack.
+    //
+    // It's possible to have both a stack overflow and a valid frame
+    // state (eg, a subexpression overflowed, visiting it returned
+    // with a dummied frame state, and visiting this expression
+    // returned with a normal-looking state).
+    if (HasStackOverflow() &&
+        !dest->is_used() &&
+        frame_->height() == original_height) {
+      dest->Goto(true);
+    }
+  }
+
+  if (force_control && !dest->is_used()) {
+    // Convert the TOS value into flow to the control destination.
+    ToBoolean(dest);
+  }
+
+  ASSERT(!(force_control && !dest->is_used()));
+  ASSERT(dest->is_used() || frame_->height() == original_height + 1);
+}
+
+
+void CodeGenerator::LoadAndSpill(Expression* expression,
+                                 TypeofState typeof_state) {
+  ASSERT(in_spilled_code());
+  set_in_spilled_code(false);
+  Load(expression, typeof_state);
+  frame_->SpillAll();
+  set_in_spilled_code(true);
+}
+
+
+void CodeGenerator::Load(Expression* x, TypeofState typeof_state) {
+#ifdef DEBUG
+  int original_height = frame_->height();
+#endif
+  ASSERT(!in_spilled_code());
+  JumpTarget true_target;
+  JumpTarget false_target;
+  ControlDestination dest(&true_target, &false_target, true);
+  LoadCondition(x, typeof_state, &dest, false);
+
+  if (dest.false_was_fall_through()) {
+    // The false target was just bound.
+    JumpTarget loaded;
+    frame_->Push(Factory::false_value());
+    // There may be dangling jumps to the true target.
+    if (true_target.is_linked()) {
+      loaded.Jump();
+      true_target.Bind();
+      frame_->Push(Factory::true_value());
+      loaded.Bind();
+    }
+
+  } else if (dest.is_used()) {
+    // There is true, and possibly false, control flow (with true as
+    // the fall through).
+    JumpTarget loaded;
+    frame_->Push(Factory::true_value());
+    if (false_target.is_linked()) {
+      loaded.Jump();
+      false_target.Bind();
+      frame_->Push(Factory::false_value());
+      loaded.Bind();
+    }
+
+  } else {
+    // We have a valid value on top of the frame, but we still may
+    // have dangling jumps to the true and false targets from nested
+    // subexpressions (eg, the left subexpressions of the
+    // short-circuited boolean operators).
+    ASSERT(has_valid_frame());
+    if (true_target.is_linked() || false_target.is_linked()) {
+      JumpTarget loaded;
+      loaded.Jump();  // Don't lose the current TOS.
+      if (true_target.is_linked()) {
+        true_target.Bind();
+        frame_->Push(Factory::true_value());
+        if (false_target.is_linked()) {
+          loaded.Jump();
+        }
+      }
+      if (false_target.is_linked()) {
+        false_target.Bind();
+        frame_->Push(Factory::false_value());
+      }
+      loaded.Bind();
+    }
+  }
+
+  ASSERT(has_valid_frame());
+  ASSERT(frame_->height() == original_height + 1);
+}
+
+
+void CodeGenerator::LoadGlobal() {
+  if (in_spilled_code()) {
+    frame_->EmitPush(GlobalObject());
+  } else {
+    Result temp = allocator_->Allocate();
+    __ mov(temp.reg(), GlobalObject());
+    frame_->Push(&temp);
+  }
+}
+
+
+void CodeGenerator::LoadGlobalReceiver() {
+  Result temp = allocator_->Allocate();
+  Register reg = temp.reg();
+  __ mov(reg, GlobalObject());
+  __ mov(reg, FieldOperand(reg, GlobalObject::kGlobalReceiverOffset));
+  frame_->Push(&temp);
+}
+
+
+// TODO(1241834): Get rid of this function in favor of just using Load, now
+// that we have the INSIDE_TYPEOF typeof state. => Need to handle global
+// variables w/o reference errors elsewhere.
+void CodeGenerator::LoadTypeofExpression(Expression* x) {
+  Variable* variable = x->AsVariableProxy()->AsVariable();
+  if (variable != NULL && !variable->is_this() && variable->is_global()) {
+    // NOTE: This is somewhat nasty. We force the compiler to load
+    // the variable as if through '<global>.<variable>' to make sure we
+    // do not get reference errors.
+    Slot global(variable, Slot::CONTEXT, Context::GLOBAL_INDEX);
+    Literal key(variable->name());
+    // TODO(1241834): Fetch the position from the variable instead of using
+    // no position.
+    Property property(&global, &key, RelocInfo::kNoPosition);
+    Load(&property);
+  } else {
+    Load(x, INSIDE_TYPEOF);
+  }
+}
+
+
+ArgumentsAllocationMode CodeGenerator::ArgumentsMode() const {
+  if (scope_->arguments() == NULL) return NO_ARGUMENTS_ALLOCATION;
+  ASSERT(scope_->arguments_shadow() != NULL);
+  // We don't want to do lazy arguments allocation for functions that
+  // have heap-allocated contexts, because it interfers with the
+  // uninitialized const tracking in the context objects.
+  return (scope_->num_heap_slots() > 0)
+      ? EAGER_ARGUMENTS_ALLOCATION
+      : LAZY_ARGUMENTS_ALLOCATION;
+}
+
+
+Result CodeGenerator::StoreArgumentsObject(bool initial) {
+  ArgumentsAllocationMode mode = ArgumentsMode();
+  ASSERT(mode != NO_ARGUMENTS_ALLOCATION);
+
+  Comment cmnt(masm_, "[ store arguments object");
+  if (mode == LAZY_ARGUMENTS_ALLOCATION && initial) {
+    // When using lazy arguments allocation, we store the hole value
+    // as a sentinel indicating that the arguments object hasn't been
+    // allocated yet.
+    frame_->Push(Factory::the_hole_value());
+  } else {
+    ArgumentsAccessStub stub(ArgumentsAccessStub::NEW_OBJECT);
+    frame_->PushFunction();
+    frame_->PushReceiverSlotAddress();
+    frame_->Push(Smi::FromInt(scope_->num_parameters()));
+    Result result = frame_->CallStub(&stub, 3);
+    frame_->Push(&result);
+  }
+
+  { Reference shadow_ref(this, scope_->arguments_shadow());
+    Reference arguments_ref(this, scope_->arguments());
+    ASSERT(shadow_ref.is_slot() && arguments_ref.is_slot());
+    // Here we rely on the convenient property that references to slot
+    // take up zero space in the frame (ie, it doesn't matter that the
+    // stored value is actually below the reference on the frame).
+    JumpTarget done;
+    bool skip_arguments = false;
+    if (mode == LAZY_ARGUMENTS_ALLOCATION && !initial) {
+      // We have to skip storing into the arguments slot if it has
+      // already been written to. This can happen if the a function
+      // has a local variable named 'arguments'.
+      LoadFromSlot(scope_->arguments()->var()->slot(), NOT_INSIDE_TYPEOF);
+      Result arguments = frame_->Pop();
+      if (arguments.is_constant()) {
+        // We have to skip updating the arguments object if it has
+        // been assigned a proper value.
+        skip_arguments = !arguments.handle()->IsTheHole();
+      } else {
+        __ cmp(Operand(arguments.reg()), Immediate(Factory::the_hole_value()));
+        arguments.Unuse();
+        done.Branch(not_equal);
+      }
+    }
+    if (!skip_arguments) {
+      arguments_ref.SetValue(NOT_CONST_INIT);
+      if (mode == LAZY_ARGUMENTS_ALLOCATION) done.Bind();
+    }
+    shadow_ref.SetValue(NOT_CONST_INIT);
+  }
+  return frame_->Pop();
+}
+
+
+Reference::Reference(CodeGenerator* cgen, Expression* expression)
+    : cgen_(cgen), expression_(expression), type_(ILLEGAL) {
+  cgen->LoadReference(this);
+}
+
+
+Reference::~Reference() {
+  cgen_->UnloadReference(this);
+}
+
+
+void CodeGenerator::LoadReference(Reference* ref) {
+  // References are loaded from both spilled and unspilled code.  Set the
+  // state to unspilled to allow that (and explicitly spill after
+  // construction at the construction sites).
+  bool was_in_spilled_code = in_spilled_code_;
+  in_spilled_code_ = false;
+
+  Comment cmnt(masm_, "[ LoadReference");
+  Expression* e = ref->expression();
+  Property* property = e->AsProperty();
+  Variable* var = e->AsVariableProxy()->AsVariable();
+
+  if (property != NULL) {
+    // The expression is either a property or a variable proxy that rewrites
+    // to a property.
+    Load(property->obj());
+    // We use a named reference if the key is a literal symbol, unless it is
+    // a string that can be legally parsed as an integer.  This is because
+    // otherwise we will not get into the slow case code that handles [] on
+    // String objects.
+    Literal* literal = property->key()->AsLiteral();
+    uint32_t dummy;
+    if (literal != NULL &&
+        literal->handle()->IsSymbol() &&
+        !String::cast(*(literal->handle()))->AsArrayIndex(&dummy)) {
+      ref->set_type(Reference::NAMED);
+    } else {
+      Load(property->key());
+      ref->set_type(Reference::KEYED);
+    }
+  } else if (var != NULL) {
+    // The expression is a variable proxy that does not rewrite to a
+    // property.  Global variables are treated as named property references.
+    if (var->is_global()) {
+      LoadGlobal();
+      ref->set_type(Reference::NAMED);
+    } else {
+      ASSERT(var->slot() != NULL);
+      ref->set_type(Reference::SLOT);
+    }
+  } else {
+    // Anything else is a runtime error.
+    Load(e);
+    frame_->CallRuntime(Runtime::kThrowReferenceError, 1);
+  }
+
+  in_spilled_code_ = was_in_spilled_code;
+}
+
+
+void CodeGenerator::UnloadReference(Reference* ref) {
+  // Pop a reference from the stack while preserving TOS.
+  Comment cmnt(masm_, "[ UnloadReference");
+  frame_->Nip(ref->size());
+}
+
+
+class ToBooleanStub: public CodeStub {
+ public:
+  ToBooleanStub() { }
+
+  void Generate(MacroAssembler* masm);
+
+ private:
+  Major MajorKey() { return ToBoolean; }
+  int MinorKey() { return 0; }
+};
+
+
+// ECMA-262, section 9.2, page 30: ToBoolean(). Pop the top of stack and
+// convert it to a boolean in the condition code register or jump to
+// 'false_target'/'true_target' as appropriate.
+void CodeGenerator::ToBoolean(ControlDestination* dest) {
+  Comment cmnt(masm_, "[ ToBoolean");
+
+  // The value to convert should be popped from the frame.
+  Result value = frame_->Pop();
+  value.ToRegister();
+  // Fast case checks.
+
+  // 'false' => false.
+  __ cmp(value.reg(), Factory::false_value());
+  dest->false_target()->Branch(equal);
+
+  // 'true' => true.
+  __ cmp(value.reg(), Factory::true_value());
+  dest->true_target()->Branch(equal);
+
+  // 'undefined' => false.
+  __ cmp(value.reg(), Factory::undefined_value());
+  dest->false_target()->Branch(equal);
+
+  // Smi => false iff zero.
+  ASSERT(kSmiTag == 0);
+  __ test(value.reg(), Operand(value.reg()));
+  dest->false_target()->Branch(zero);
+  __ test(value.reg(), Immediate(kSmiTagMask));
+  dest->true_target()->Branch(zero);
+
+  // Call the stub for all other cases.
+  frame_->Push(&value);  // Undo the Pop() from above.
+  ToBooleanStub stub;
+  Result temp = frame_->CallStub(&stub, 1);
+  // Convert the result to a condition code.
+  __ test(temp.reg(), Operand(temp.reg()));
+  temp.Unuse();
+  dest->Split(not_equal);
+}
+
+
+class FloatingPointHelper : public AllStatic {
+ public:
+  // Code pattern for loading a floating point value. Input value must
+  // be either a smi or a heap number object (fp value). Requirements:
+  // operand in register number. Returns operand as floating point number
+  // on FPU stack.
+  static void LoadFloatOperand(MacroAssembler* masm, Register number);
+  // Code pattern for loading floating point values. Input values must
+  // be either smi or heap number objects (fp values). Requirements:
+  // operand_1 on TOS+1 , operand_2 on TOS+2; Returns operands as
+  // floating point numbers on FPU stack.
+  static void LoadFloatOperands(MacroAssembler* masm, Register scratch);
+  // Test if operands are smi or number objects (fp). Requirements:
+  // operand_1 in eax, operand_2 in edx; falls through on float
+  // operands, jumps to the non_float label otherwise.
+  static void CheckFloatOperands(MacroAssembler* masm,
+                                 Label* non_float,
+                                 Register scratch);
+  // Test if operands are numbers (smi or HeapNumber objects), and load
+  // them into xmm0 and xmm1 if they are.  Jump to label not_numbers if
+  // either operand is not a number.  Operands are in edx and eax.
+  // Leaves operands unchanged.
+  static void LoadSse2Operands(MacroAssembler* masm, Label* not_numbers);
+  // Allocate a heap number in new space with undefined value.
+  // Returns tagged pointer in eax, or jumps to need_gc if new space is full.
+  static void AllocateHeapNumber(MacroAssembler* masm,
+                                 Label* need_gc,
+                                 Register scratch1,
+                                 Register scratch2,
+                                 Register result);
+};
+
+
+const char* GenericBinaryOpStub::GetName() {
+  switch (op_) {
+    case Token::ADD: return "GenericBinaryOpStub_ADD";
+    case Token::SUB: return "GenericBinaryOpStub_SUB";
+    case Token::MUL: return "GenericBinaryOpStub_MUL";
+    case Token::DIV: return "GenericBinaryOpStub_DIV";
+    case Token::BIT_OR: return "GenericBinaryOpStub_BIT_OR";
+    case Token::BIT_AND: return "GenericBinaryOpStub_BIT_AND";
+    case Token::BIT_XOR: return "GenericBinaryOpStub_BIT_XOR";
+    case Token::SAR: return "GenericBinaryOpStub_SAR";
+    case Token::SHL: return "GenericBinaryOpStub_SHL";
+    case Token::SHR: return "GenericBinaryOpStub_SHR";
+    default:         return "GenericBinaryOpStub";
+  }
+}
+
+
+// Call the specialized stub for a binary operation.
+class DeferredInlineBinaryOperation: public DeferredCode {
+ public:
+  DeferredInlineBinaryOperation(Token::Value op,
+                                Register dst,
+                                Register left,
+                                Register right,
+                                OverwriteMode mode)
+      : op_(op), dst_(dst), left_(left), right_(right), mode_(mode) {
+    set_comment("[ DeferredInlineBinaryOperation");
+  }
+
+  virtual void Generate();
+
+ private:
+  Token::Value op_;
+  Register dst_;
+  Register left_;
+  Register right_;
+  OverwriteMode mode_;
+};
+
+
+void DeferredInlineBinaryOperation::Generate() {
+  __ push(left_);
+  __ push(right_);
+  GenericBinaryOpStub stub(op_, mode_, SMI_CODE_INLINED);
+  __ CallStub(&stub);
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+}
+
+
+void CodeGenerator::GenericBinaryOperation(Token::Value op,
+                                           SmiAnalysis* type,
+                                           OverwriteMode overwrite_mode) {
+  Comment cmnt(masm_, "[ BinaryOperation");
+  Comment cmnt_token(masm_, Token::String(op));
+
+  if (op == Token::COMMA) {
+    // Simply discard left value.
+    frame_->Nip(1);
+    return;
+  }
+
+  // Set the flags based on the operation, type and loop nesting level.
+  GenericBinaryFlags flags;
+  switch (op) {
+    case Token::BIT_OR:
+    case Token::BIT_AND:
+    case Token::BIT_XOR:
+    case Token::SHL:
+    case Token::SHR:
+    case Token::SAR:
+      // Bit operations always assume they likely operate on Smis. Still only
+      // generate the inline Smi check code if this operation is part of a loop.
+      flags = (loop_nesting() > 0)
+              ? SMI_CODE_INLINED
+              : SMI_CODE_IN_STUB;
+      break;
+
+    default:
+      // By default only inline the Smi check code for likely smis if this
+      // operation is part of a loop.
+      flags = ((loop_nesting() > 0) && type->IsLikelySmi())
+              ? SMI_CODE_INLINED
+              : SMI_CODE_IN_STUB;
+      break;
+  }
+
+  Result right = frame_->Pop();
+  Result left = frame_->Pop();
+
+  if (op == Token::ADD) {
+    bool left_is_string = left.is_constant() && left.handle()->IsString();
+    bool right_is_string = right.is_constant() && right.handle()->IsString();
+    if (left_is_string || right_is_string) {
+      frame_->Push(&left);
+      frame_->Push(&right);
+      Result answer;
+      if (left_is_string) {
+        if (right_is_string) {
+          // TODO(lrn): if both are constant strings
+          // -- do a compile time cons, if allocation during codegen is allowed.
+          answer = frame_->CallRuntime(Runtime::kStringAdd, 2);
+        } else {
+          answer =
+            frame_->InvokeBuiltin(Builtins::STRING_ADD_LEFT, CALL_FUNCTION, 2);
+        }
+      } else if (right_is_string) {
+        answer =
+          frame_->InvokeBuiltin(Builtins::STRING_ADD_RIGHT, CALL_FUNCTION, 2);
+      }
+      frame_->Push(&answer);
+      return;
+    }
+    // Neither operand is known to be a string.
+  }
+
+  bool left_is_smi = left.is_constant() && left.handle()->IsSmi();
+  bool left_is_non_smi = left.is_constant() && !left.handle()->IsSmi();
+  bool right_is_smi = right.is_constant() && right.handle()->IsSmi();
+  bool right_is_non_smi = right.is_constant() && !right.handle()->IsSmi();
+  bool generate_no_smi_code = false;  // No smi code at all, inline or in stub.
+
+  if (left_is_smi && right_is_smi) {
+    // Compute the constant result at compile time, and leave it on the frame.
+    int left_int = Smi::cast(*left.handle())->value();
+    int right_int = Smi::cast(*right.handle())->value();
+    if (FoldConstantSmis(op, left_int, right_int)) return;
+  }
+
+  if (left_is_non_smi || right_is_non_smi) {
+    // Set flag so that we go straight to the slow case, with no smi code.
+    generate_no_smi_code = true;
+  } else if (right_is_smi) {
+    ConstantSmiBinaryOperation(op, &left, right.handle(),
+                               type, false, overwrite_mode);
+    return;
+  } else if (left_is_smi) {
+    ConstantSmiBinaryOperation(op, &right, left.handle(),
+                               type, true, overwrite_mode);
+    return;
+  }
+
+  if (flags == SMI_CODE_INLINED && !generate_no_smi_code) {
+    LikelySmiBinaryOperation(op, &left, &right, overwrite_mode);
+  } else {
+    frame_->Push(&left);
+    frame_->Push(&right);
+    // If we know the arguments aren't smis, use the binary operation stub
+    // that does not check for the fast smi case.
+    // The same stub is used for NO_SMI_CODE and SMI_CODE_INLINED.
+    if (generate_no_smi_code) {
+      flags = SMI_CODE_INLINED;
+    }
+    GenericBinaryOpStub stub(op, overwrite_mode, flags);
+    Result answer = frame_->CallStub(&stub, 2);
+    frame_->Push(&answer);
+  }
+}
+
+
+bool CodeGenerator::FoldConstantSmis(Token::Value op, int left, int right) {
+  Object* answer_object = Heap::undefined_value();
+  switch (op) {
+    case Token::ADD:
+      if (Smi::IsValid(left + right)) {
+        answer_object = Smi::FromInt(left + right);
+      }
+      break;
+    case Token::SUB:
+      if (Smi::IsValid(left - right)) {
+        answer_object = Smi::FromInt(left - right);
+      }
+      break;
+    case Token::MUL: {
+        double answer = static_cast<double>(left) * right;
+        if (answer >= Smi::kMinValue && answer <= Smi::kMaxValue) {
+          // If the product is zero and the non-zero factor is negative,
+          // the spec requires us to return floating point negative zero.
+          if (answer != 0 || (left >= 0 && right >= 0)) {
+            answer_object = Smi::FromInt(static_cast<int>(answer));
+          }
+        }
+      }
+      break;
+    case Token::DIV:
+    case Token::MOD:
+      break;
+    case Token::BIT_OR:
+      answer_object = Smi::FromInt(left | right);
+      break;
+    case Token::BIT_AND:
+      answer_object = Smi::FromInt(left & right);
+      break;
+    case Token::BIT_XOR:
+      answer_object = Smi::FromInt(left ^ right);
+      break;
+
+    case Token::SHL: {
+        int shift_amount = right & 0x1F;
+        if (Smi::IsValid(left << shift_amount)) {
+          answer_object = Smi::FromInt(left << shift_amount);
+        }
+        break;
+      }
+    case Token::SHR: {
+        int shift_amount = right & 0x1F;
+        unsigned int unsigned_left = left;
+        unsigned_left >>= shift_amount;
+        if (unsigned_left <= static_cast<unsigned int>(Smi::kMaxValue)) {
+          answer_object = Smi::FromInt(unsigned_left);
+        }
+        break;
+      }
+    case Token::SAR: {
+        int shift_amount = right & 0x1F;
+        unsigned int unsigned_left = left;
+        if (left < 0) {
+          // Perform arithmetic shift of a negative number by
+          // complementing number, logical shifting, complementing again.
+          unsigned_left = ~unsigned_left;
+          unsigned_left >>= shift_amount;
+          unsigned_left = ~unsigned_left;
+        } else {
+          unsigned_left >>= shift_amount;
+        }
+        ASSERT(Smi::IsValid(unsigned_left));  // Converted to signed.
+        answer_object = Smi::FromInt(unsigned_left);  // Converted to signed.
+        break;
+      }
+    default:
+      UNREACHABLE();
+      break;
+  }
+  if (answer_object == Heap::undefined_value()) {
+    return false;
+  }
+  frame_->Push(Handle<Object>(answer_object));
+  return true;
+}
+
+
+// Implements a binary operation using a deferred code object and some
+// inline code to operate on smis quickly.
+void CodeGenerator::LikelySmiBinaryOperation(Token::Value op,
+                                             Result* left,
+                                             Result* right,
+                                             OverwriteMode overwrite_mode) {
+  // Special handling of div and mod because they use fixed registers.
+  if (op == Token::DIV || op == Token::MOD) {
+    // We need eax as the quotient register, edx as the remainder
+    // register, neither left nor right in eax or edx, and left copied
+    // to eax.
+    Result quotient;
+    Result remainder;
+    bool left_is_in_eax = false;
+    // Step 1: get eax for quotient.
+    if ((left->is_register() && left->reg().is(eax)) ||
+        (right->is_register() && right->reg().is(eax))) {
+      // One or both is in eax.  Use a fresh non-edx register for
+      // them.
+      Result fresh = allocator_->Allocate();
+      ASSERT(fresh.is_valid());
+      if (fresh.reg().is(edx)) {
+        remainder = fresh;
+        fresh = allocator_->Allocate();
+        ASSERT(fresh.is_valid());
+      }
+      if (left->is_register() && left->reg().is(eax)) {
+        quotient = *left;
+        *left = fresh;
+        left_is_in_eax = true;
+      }
+      if (right->is_register() && right->reg().is(eax)) {
+        quotient = *right;
+        *right = fresh;
+      }
+      __ mov(fresh.reg(), eax);
+    } else {
+      // Neither left nor right is in eax.
+      quotient = allocator_->Allocate(eax);
+    }
+    ASSERT(quotient.is_register() && quotient.reg().is(eax));
+    ASSERT(!(left->is_register() && left->reg().is(eax)));
+    ASSERT(!(right->is_register() && right->reg().is(eax)));
+
+    // Step 2: get edx for remainder if necessary.
+    if (!remainder.is_valid()) {
+      if ((left->is_register() && left->reg().is(edx)) ||
+          (right->is_register() && right->reg().is(edx))) {
+        Result fresh = allocator_->Allocate();
+        ASSERT(fresh.is_valid());
+        if (left->is_register() && left->reg().is(edx)) {
+          remainder = *left;
+          *left = fresh;
+        }
+        if (right->is_register() && right->reg().is(edx)) {
+          remainder = *right;
+          *right = fresh;
+        }
+        __ mov(fresh.reg(), edx);
+      } else {
+        // Neither left nor right is in edx.
+        remainder = allocator_->Allocate(edx);
+      }
+    }
+    ASSERT(remainder.is_register() && remainder.reg().is(edx));
+    ASSERT(!(left->is_register() && left->reg().is(edx)));
+    ASSERT(!(right->is_register() && right->reg().is(edx)));
+
+    left->ToRegister();
+    right->ToRegister();
+    frame_->Spill(eax);
+    frame_->Spill(edx);
+
+    // Check that left and right are smi tagged.
+    DeferredInlineBinaryOperation* deferred =
+        new DeferredInlineBinaryOperation(op,
+                                          (op == Token::DIV) ? eax : edx,
+                                          left->reg(),
+                                          right->reg(),
+                                          overwrite_mode);
+    if (left->reg().is(right->reg())) {
+      __ test(left->reg(), Immediate(kSmiTagMask));
+    } else {
+      // Use the quotient register as a scratch for the tag check.
+      if (!left_is_in_eax) __ mov(eax, left->reg());
+      left_is_in_eax = false;  // About to destroy the value in eax.
+      __ or_(eax, Operand(right->reg()));
+      ASSERT(kSmiTag == 0);  // Adjust test if not the case.
+      __ test(eax, Immediate(kSmiTagMask));
+    }
+    deferred->Branch(not_zero);
+
+    if (!left_is_in_eax) __ mov(eax, left->reg());
+    // Sign extend eax into edx:eax.
+    __ cdq();
+    // Check for 0 divisor.
+    __ test(right->reg(), Operand(right->reg()));
+    deferred->Branch(zero);
+    // Divide edx:eax by the right operand.
+    __ idiv(right->reg());
+
+    // Complete the operation.
+    if (op == Token::DIV) {
+      // Check for negative zero result.  If result is zero, and divisor
+      // is negative, return a floating point negative zero.  The
+      // virtual frame is unchanged in this block, so local control flow
+      // can use a Label rather than a JumpTarget.
+      Label non_zero_result;
+      __ test(left->reg(), Operand(left->reg()));
+      __ j(not_zero, &non_zero_result);
+      __ test(right->reg(), Operand(right->reg()));
+      deferred->Branch(negative);
+      __ bind(&non_zero_result);
+      // Check for the corner case of dividing the most negative smi by
+      // -1. We cannot use the overflow flag, since it is not set by
+      // idiv instruction.
+      ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
+      __ cmp(eax, 0x40000000);
+      deferred->Branch(equal);
+      // Check that the remainder is zero.
+      __ test(edx, Operand(edx));
+      deferred->Branch(not_zero);
+      // Tag the result and store it in the quotient register.
+      ASSERT(kSmiTagSize == times_2);  // adjust code if not the case
+      __ lea(eax, Operand(eax, eax, times_1, kSmiTag));
+      deferred->BindExit();
+      left->Unuse();
+      right->Unuse();
+      frame_->Push(&quotient);
+    } else {
+      ASSERT(op == Token::MOD);
+      // Check for a negative zero result.  If the result is zero, and
+      // the dividend is negative, return a floating point negative
+      // zero.  The frame is unchanged in this block, so local control
+      // flow can use a Label rather than a JumpTarget.
+      Label non_zero_result;
+      __ test(edx, Operand(edx));
+      __ j(not_zero, &non_zero_result, taken);
+      __ test(left->reg(), Operand(left->reg()));
+      deferred->Branch(negative);
+      __ bind(&non_zero_result);
+      deferred->BindExit();
+      left->Unuse();
+      right->Unuse();
+      frame_->Push(&remainder);
+    }
+    return;
+  }
+
+  // Special handling of shift operations because they use fixed
+  // registers.
+  if (op == Token::SHL || op == Token::SHR || op == Token::SAR) {
+    // Move left out of ecx if necessary.
+    if (left->is_register() && left->reg().is(ecx)) {
+      *left = allocator_->Allocate();
+      ASSERT(left->is_valid());
+      __ mov(left->reg(), ecx);
+    }
+    right->ToRegister(ecx);
+    left->ToRegister();
+    ASSERT(left->is_register() && !left->reg().is(ecx));
+    ASSERT(right->is_register() && right->reg().is(ecx));
+
+    // We will modify right, it must be spilled.
+    frame_->Spill(ecx);
+
+    // Use a fresh answer register to avoid spilling the left operand.
+    Result answer = allocator_->Allocate();
+    ASSERT(answer.is_valid());
+    // Check that both operands are smis using the answer register as a
+    // temporary.
+    DeferredInlineBinaryOperation* deferred =
+        new DeferredInlineBinaryOperation(op,
+                                          answer.reg(),
+                                          left->reg(),
+                                          ecx,
+                                          overwrite_mode);
+    __ mov(answer.reg(), left->reg());
+    __ or_(answer.reg(), Operand(ecx));
+    __ test(answer.reg(), Immediate(kSmiTagMask));
+    deferred->Branch(not_zero);
+
+    // Untag both operands.
+    __ mov(answer.reg(), left->reg());
+    __ sar(answer.reg(), kSmiTagSize);
+    __ sar(ecx, kSmiTagSize);
+    // Perform the operation.
+    switch (op) {
+      case Token::SAR:
+        __ sar(answer.reg());
+        // No checks of result necessary
+        break;
+      case Token::SHR: {
+        Label result_ok;
+        __ shr(answer.reg());
+        // Check that the *unsigned* result fits in a smi.  Neither of
+        // the two high-order bits can be set:
+        //  * 0x80000000: high bit would be lost when smi tagging.
+        //  * 0x40000000: this number would convert to negative when smi
+        //    tagging.
+        // These two cases can only happen with shifts by 0 or 1 when
+        // handed a valid smi.  If the answer cannot be represented by a
+        // smi, restore the left and right arguments, and jump to slow
+        // case.  The low bit of the left argument may be lost, but only
+        // in a case where it is dropped anyway.
+        __ test(answer.reg(), Immediate(0xc0000000));
+        __ j(zero, &result_ok);
+        ASSERT(kSmiTag == 0);
+        __ shl(ecx, kSmiTagSize);
+        deferred->Jump();
+        __ bind(&result_ok);
+        break;
+      }
+      case Token::SHL: {
+        Label result_ok;
+        __ shl(answer.reg());
+        // Check that the *signed* result fits in a smi.
+        __ cmp(answer.reg(), 0xc0000000);
+        __ j(positive, &result_ok);
+        ASSERT(kSmiTag == 0);
+        __ shl(ecx, kSmiTagSize);
+        deferred->Jump();
+        __ bind(&result_ok);
+        break;
+      }
+      default:
+        UNREACHABLE();
+    }
+    // Smi-tag the result in answer.
+    ASSERT(kSmiTagSize == 1);  // Adjust code if not the case.
+    __ lea(answer.reg(),
+           Operand(answer.reg(), answer.reg(), times_1, kSmiTag));
+    deferred->BindExit();
+    left->Unuse();
+    right->Unuse();
+    frame_->Push(&answer);
+    return;
+  }
+
+  // Handle the other binary operations.
+  left->ToRegister();
+  right->ToRegister();
+  // A newly allocated register answer is used to hold the answer.  The
+  // registers containing left and right are not modified so they don't
+  // need to be spilled in the fast case.
+  Result answer = allocator_->Allocate();
+  ASSERT(answer.is_valid());
+
+  // Perform the smi tag check.
+  DeferredInlineBinaryOperation* deferred =
+      new DeferredInlineBinaryOperation(op,
+                                        answer.reg(),
+                                        left->reg(),
+                                        right->reg(),
+                                        overwrite_mode);
+  if (left->reg().is(right->reg())) {
+    __ test(left->reg(), Immediate(kSmiTagMask));
+  } else {
+    __ mov(answer.reg(), left->reg());
+    __ or_(answer.reg(), Operand(right->reg()));
+    ASSERT(kSmiTag == 0);  // Adjust test if not the case.
+    __ test(answer.reg(), Immediate(kSmiTagMask));
+  }
+  deferred->Branch(not_zero);
+  __ mov(answer.reg(), left->reg());
+  switch (op) {
+    case Token::ADD:
+      __ add(answer.reg(), Operand(right->reg()));  // Add optimistically.
+      deferred->Branch(overflow);
+      break;
+
+    case Token::SUB:
+      __ sub(answer.reg(), Operand(right->reg()));  // Subtract optimistically.
+      deferred->Branch(overflow);
+      break;
+
+    case Token::MUL: {
+      // If the smi tag is 0 we can just leave the tag on one operand.
+      ASSERT(kSmiTag == 0);  // Adjust code below if not the case.
+      // Remove smi tag from the left operand (but keep sign).
+      // Left-hand operand has been copied into answer.
+      __ sar(answer.reg(), kSmiTagSize);
+      // Do multiplication of smis, leaving result in answer.
+      __ imul(answer.reg(), Operand(right->reg()));
+      // Go slow on overflows.
+      deferred->Branch(overflow);
+      // Check for negative zero result.  If product is zero, and one
+      // argument is negative, go to slow case.  The frame is unchanged
+      // in this block, so local control flow can use a Label rather
+      // than a JumpTarget.
+      Label non_zero_result;
+      __ test(answer.reg(), Operand(answer.reg()));
+      __ j(not_zero, &non_zero_result, taken);
+      __ mov(answer.reg(), left->reg());
+      __ or_(answer.reg(), Operand(right->reg()));
+      deferred->Branch(negative);
+      __ xor_(answer.reg(), Operand(answer.reg()));  // Positive 0 is correct.
+      __ bind(&non_zero_result);
+      break;
+    }
+
+    case Token::BIT_OR:
+      __ or_(answer.reg(), Operand(right->reg()));
+      break;
+
+    case Token::BIT_AND:
+      __ and_(answer.reg(), Operand(right->reg()));
+      break;
+
+    case Token::BIT_XOR:
+      __ xor_(answer.reg(), Operand(right->reg()));
+      break;
+
+    default:
+      UNREACHABLE();
+      break;
+  }
+  deferred->BindExit();
+  left->Unuse();
+  right->Unuse();
+  frame_->Push(&answer);
+}
+
+
+// Call the appropriate binary operation stub to compute src op value
+// and leave the result in dst.
+class DeferredInlineSmiOperation: public DeferredCode {
+ public:
+  DeferredInlineSmiOperation(Token::Value op,
+                             Register dst,
+                             Register src,
+                             Smi* value,
+                             OverwriteMode overwrite_mode)
+      : op_(op),
+        dst_(dst),
+        src_(src),
+        value_(value),
+        overwrite_mode_(overwrite_mode) {
+    set_comment("[ DeferredInlineSmiOperation");
+  }
+
+  virtual void Generate();
+
+ private:
+  Token::Value op_;
+  Register dst_;
+  Register src_;
+  Smi* value_;
+  OverwriteMode overwrite_mode_;
+};
+
+
+void DeferredInlineSmiOperation::Generate() {
+  __ push(src_);
+  __ push(Immediate(value_));
+  // For mod we don't generate all the Smi code inline.
+  GenericBinaryOpStub stub(
+      op_,
+      overwrite_mode_,
+      (op_ == Token::MOD) ? SMI_CODE_IN_STUB : SMI_CODE_INLINED);
+  __ CallStub(&stub);
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+}
+
+
+// Call the appropriate binary operation stub to compute value op src
+// and leave the result in dst.
+class DeferredInlineSmiOperationReversed: public DeferredCode {
+ public:
+  DeferredInlineSmiOperationReversed(Token::Value op,
+                                     Register dst,
+                                     Smi* value,
+                                     Register src,
+                                     OverwriteMode overwrite_mode)
+      : op_(op),
+        dst_(dst),
+        value_(value),
+        src_(src),
+        overwrite_mode_(overwrite_mode) {
+    set_comment("[ DeferredInlineSmiOperationReversed");
+  }
+
+  virtual void Generate();
+
+ private:
+  Token::Value op_;
+  Register dst_;
+  Smi* value_;
+  Register src_;
+  OverwriteMode overwrite_mode_;
+};
+
+
+void DeferredInlineSmiOperationReversed::Generate() {
+  __ push(Immediate(value_));
+  __ push(src_);
+  GenericBinaryOpStub igostub(op_, overwrite_mode_, SMI_CODE_INLINED);
+  __ CallStub(&igostub);
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+}
+
+
+// The result of src + value is in dst.  It either overflowed or was not
+// smi tagged.  Undo the speculative addition and call the appropriate
+// specialized stub for add.  The result is left in dst.
+class DeferredInlineSmiAdd: public DeferredCode {
+ public:
+  DeferredInlineSmiAdd(Register dst,
+                       Smi* value,
+                       OverwriteMode overwrite_mode)
+      : dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
+    set_comment("[ DeferredInlineSmiAdd");
+  }
+
+  virtual void Generate();
+
+ private:
+  Register dst_;
+  Smi* value_;
+  OverwriteMode overwrite_mode_;
+};
+
+
+void DeferredInlineSmiAdd::Generate() {
+  // Undo the optimistic add operation and call the shared stub.
+  __ sub(Operand(dst_), Immediate(value_));
+  __ push(dst_);
+  __ push(Immediate(value_));
+  GenericBinaryOpStub igostub(Token::ADD, overwrite_mode_, SMI_CODE_INLINED);
+  __ CallStub(&igostub);
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+}
+
+
+// The result of value + src is in dst.  It either overflowed or was not
+// smi tagged.  Undo the speculative addition and call the appropriate
+// specialized stub for add.  The result is left in dst.
+class DeferredInlineSmiAddReversed: public DeferredCode {
+ public:
+  DeferredInlineSmiAddReversed(Register dst,
+                               Smi* value,
+                               OverwriteMode overwrite_mode)
+      : dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
+    set_comment("[ DeferredInlineSmiAddReversed");
+  }
+
+  virtual void Generate();
+
+ private:
+  Register dst_;
+  Smi* value_;
+  OverwriteMode overwrite_mode_;
+};
+
+
+void DeferredInlineSmiAddReversed::Generate() {
+  // Undo the optimistic add operation and call the shared stub.
+  __ sub(Operand(dst_), Immediate(value_));
+  __ push(Immediate(value_));
+  __ push(dst_);
+  GenericBinaryOpStub igostub(Token::ADD, overwrite_mode_, SMI_CODE_INLINED);
+  __ CallStub(&igostub);
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+}
+
+
+// The result of src - value is in dst.  It either overflowed or was not
+// smi tagged.  Undo the speculative subtraction and call the
+// appropriate specialized stub for subtract.  The result is left in
+// dst.
+class DeferredInlineSmiSub: public DeferredCode {
+ public:
+  DeferredInlineSmiSub(Register dst,
+                       Smi* value,
+                       OverwriteMode overwrite_mode)
+      : dst_(dst), value_(value), overwrite_mode_(overwrite_mode) {
+    set_comment("[ DeferredInlineSmiSub");
+  }
+
+  virtual void Generate();
+
+ private:
+  Register dst_;
+  Smi* value_;
+  OverwriteMode overwrite_mode_;
+};
+
+
+void DeferredInlineSmiSub::Generate() {
+  // Undo the optimistic sub operation and call the shared stub.
+  __ add(Operand(dst_), Immediate(value_));
+  __ push(dst_);
+  __ push(Immediate(value_));
+  GenericBinaryOpStub igostub(Token::SUB, overwrite_mode_, SMI_CODE_INLINED);
+  __ CallStub(&igostub);
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+}
+
+
+void CodeGenerator::ConstantSmiBinaryOperation(Token::Value op,
+                                               Result* operand,
+                                               Handle<Object> value,
+                                               SmiAnalysis* type,
+                                               bool reversed,
+                                               OverwriteMode overwrite_mode) {
+  // NOTE: This is an attempt to inline (a bit) more of the code for
+  // some possible smi operations (like + and -) when (at least) one
+  // of the operands is a constant smi.
+  // Consumes the argument "operand".
+
+  // TODO(199): Optimize some special cases of operations involving a
+  // smi literal (multiply by 2, shift by 0, etc.).
+  if (IsUnsafeSmi(value)) {
+    Result unsafe_operand(value);
+    if (reversed) {
+      LikelySmiBinaryOperation(op, &unsafe_operand, operand,
+                               overwrite_mode);
+    } else {
+      LikelySmiBinaryOperation(op, operand, &unsafe_operand,
+                               overwrite_mode);
+    }
+    ASSERT(!operand->is_valid());
+    return;
+  }
+
+  // Get the literal value.
+  Smi* smi_value = Smi::cast(*value);
+  int int_value = smi_value->value();
+
+  switch (op) {
+    case Token::ADD: {
+      operand->ToRegister();
+      frame_->Spill(operand->reg());
+
+      // Optimistically add.  Call the specialized add stub if the
+      // result is not a smi or overflows.
+      DeferredCode* deferred = NULL;
+      if (reversed) {
+        deferred = new DeferredInlineSmiAddReversed(operand->reg(),
+                                                    smi_value,
+                                                    overwrite_mode);
+      } else {
+        deferred = new DeferredInlineSmiAdd(operand->reg(),
+                                            smi_value,
+                                            overwrite_mode);
+      }
+      __ add(Operand(operand->reg()), Immediate(value));
+      deferred->Branch(overflow);
+      __ test(operand->reg(), Immediate(kSmiTagMask));
+      deferred->Branch(not_zero);
+      deferred->BindExit();
+      frame_->Push(operand);
+      break;
+    }
+
+    case Token::SUB: {
+      DeferredCode* deferred = NULL;
+      Result answer;  // Only allocate a new register if reversed.
+      if (reversed) {
+        // The reversed case is only hit when the right operand is not a
+        // constant.
+        ASSERT(operand->is_register());
+        answer = allocator()->Allocate();
+        ASSERT(answer.is_valid());
+        __ Set(answer.reg(), Immediate(value));
+        deferred = new DeferredInlineSmiOperationReversed(op,
+                                                          answer.reg(),
+                                                          smi_value,
+                                                          operand->reg(),
+                                                          overwrite_mode);
+        __ sub(answer.reg(), Operand(operand->reg()));
+      } else {
+        operand->ToRegister();
+        frame_->Spill(operand->reg());
+        answer = *operand;
+        deferred = new DeferredInlineSmiSub(operand->reg(),
+                                            smi_value,
+                                            overwrite_mode);
+        __ sub(Operand(operand->reg()), Immediate(value));
+      }
+      deferred->Branch(overflow);
+      __ test(answer.reg(), Immediate(kSmiTagMask));
+      deferred->Branch(not_zero);
+      deferred->BindExit();
+      operand->Unuse();
+      frame_->Push(&answer);
+      break;
+    }
+
+    case Token::SAR:
+      if (reversed) {
+        Result constant_operand(value);
+        LikelySmiBinaryOperation(op, &constant_operand, operand,
+                                 overwrite_mode);
+      } else {
+        // Only the least significant 5 bits of the shift value are used.
+        // In the slow case, this masking is done inside the runtime call.
+        int shift_value = int_value & 0x1f;
+        operand->ToRegister();
+        frame_->Spill(operand->reg());
+        DeferredInlineSmiOperation* deferred =
+            new DeferredInlineSmiOperation(op,
+                                           operand->reg(),
+                                           operand->reg(),
+                                           smi_value,
+                                           overwrite_mode);
+        __ test(operand->reg(), Immediate(kSmiTagMask));
+        deferred->Branch(not_zero);
+        if (shift_value > 0) {
+          __ sar(operand->reg(), shift_value);
+          __ and_(operand->reg(), ~kSmiTagMask);
+        }
+        deferred->BindExit();
+        frame_->Push(operand);
+      }
+      break;
+
+    case Token::SHR:
+      if (reversed) {
+        Result constant_operand(value);
+        LikelySmiBinaryOperation(op, &constant_operand, operand,
+                                 overwrite_mode);
+      } else {
+        // Only the least significant 5 bits of the shift value are used.
+        // In the slow case, this masking is done inside the runtime call.
+        int shift_value = int_value & 0x1f;
+        operand->ToRegister();
+        Result answer = allocator()->Allocate();
+        ASSERT(answer.is_valid());
+        DeferredInlineSmiOperation* deferred =
+            new DeferredInlineSmiOperation(op,
+                                           answer.reg(),
+                                           operand->reg(),
+                                           smi_value,
+                                           overwrite_mode);
+        __ test(operand->reg(), Immediate(kSmiTagMask));
+        deferred->Branch(not_zero);
+        __ mov(answer.reg(), operand->reg());
+        __ sar(answer.reg(), kSmiTagSize);
+        __ shr(answer.reg(), shift_value);
+        // A negative Smi shifted right two is in the positive Smi range.
+        if (shift_value < 2) {
+          __ test(answer.reg(), Immediate(0xc0000000));
+          deferred->Branch(not_zero);
+        }
+        operand->Unuse();
+        ASSERT(kSmiTagSize == times_2);  // Adjust the code if not true.
+        __ lea(answer.reg(),
+               Operand(answer.reg(), answer.reg(), times_1, kSmiTag));
+        deferred->BindExit();
+        frame_->Push(&answer);
+      }
+      break;
+
+    case Token::SHL:
+      if (reversed) {
+        Result constant_operand(value);
+        LikelySmiBinaryOperation(op, &constant_operand, operand,
+                                 overwrite_mode);
+      } else {
+        // Only the least significant 5 bits of the shift value are used.
+        // In the slow case, this masking is done inside the runtime call.
+        int shift_value = int_value & 0x1f;
+        operand->ToRegister();
+        if (shift_value == 0) {
+          // Spill operand so it can be overwritten in the slow case.
+          frame_->Spill(operand->reg());
+          DeferredInlineSmiOperation* deferred =
+              new DeferredInlineSmiOperation(op,
+                                             operand->reg(),
+                                             operand->reg(),
+                                             smi_value,
+                                             overwrite_mode);
+          __ test(operand->reg(), Immediate(kSmiTagMask));
+          deferred->Branch(not_zero);
+          deferred->BindExit();
+          frame_->Push(operand);
+        } else {
+          // Use a fresh temporary for nonzero shift values.
+          Result answer = allocator()->Allocate();
+          ASSERT(answer.is_valid());
+          DeferredInlineSmiOperation* deferred =
+              new DeferredInlineSmiOperation(op,
+                                             answer.reg(),
+                                             operand->reg(),
+                                             smi_value,
+                                             overwrite_mode);
+          __ test(operand->reg(), Immediate(kSmiTagMask));
+          deferred->Branch(not_zero);
+          __ mov(answer.reg(), operand->reg());
+          ASSERT(kSmiTag == 0);  // adjust code if not the case
+          // We do no shifts, only the Smi conversion, if shift_value is 1.
+          if (shift_value > 1) {
+            __ shl(answer.reg(), shift_value - 1);
+          }
+          // Convert int result to Smi, checking that it is in int range.
+          ASSERT(kSmiTagSize == 1);  // adjust code if not the case
+          __ add(answer.reg(), Operand(answer.reg()));
+          deferred->Branch(overflow);
+          deferred->BindExit();
+          operand->Unuse();
+          frame_->Push(&answer);
+        }
+      }
+      break;
+
+    case Token::BIT_OR:
+    case Token::BIT_XOR:
+    case Token::BIT_AND: {
+      operand->ToRegister();
+      frame_->Spill(operand->reg());
+      DeferredCode* deferred = NULL;
+      if (reversed) {
+        deferred = new DeferredInlineSmiOperationReversed(op,
+                                                          operand->reg(),
+                                                          smi_value,
+                                                          operand->reg(),
+                                                          overwrite_mode);
+      } else {
+        deferred =  new DeferredInlineSmiOperation(op,
+                                                   operand->reg(),
+                                                   operand->reg(),
+                                                   smi_value,
+                                                   overwrite_mode);
+      }
+      __ test(operand->reg(), Immediate(kSmiTagMask));
+      deferred->Branch(not_zero);
+      if (op == Token::BIT_AND) {
+        __ and_(Operand(operand->reg()), Immediate(value));
+      } else if (op == Token::BIT_XOR) {
+        if (int_value != 0) {
+          __ xor_(Operand(operand->reg()), Immediate(value));
+        }
+      } else {
+        ASSERT(op == Token::BIT_OR);
+        if (int_value != 0) {
+          __ or_(Operand(operand->reg()), Immediate(value));
+        }
+      }
+      deferred->BindExit();
+      frame_->Push(operand);
+      break;
+    }
+
+    // Generate inline code for mod of powers of 2 and negative powers of 2.
+    case Token::MOD:
+      if (!reversed &&
+          int_value != 0 &&
+          (IsPowerOf2(int_value) || IsPowerOf2(-int_value))) {
+        operand->ToRegister();
+        frame_->Spill(operand->reg());
+        DeferredCode* deferred = new DeferredInlineSmiOperation(op,
+                                                                operand->reg(),
+                                                                operand->reg(),
+                                                                smi_value,
+                                                                overwrite_mode);
+        // Check for negative or non-Smi left hand side.
+        __ test(operand->reg(), Immediate(kSmiTagMask | 0x80000000));
+        deferred->Branch(not_zero);
+        if (int_value < 0) int_value = -int_value;
+        if (int_value == 1) {
+          __ mov(operand->reg(), Immediate(Smi::FromInt(0)));
+        } else {
+          __ and_(operand->reg(), (int_value << kSmiTagSize) - 1);
+        }
+        deferred->BindExit();
+        frame_->Push(operand);
+        break;
+      }
+      // Fall through if we did not find a power of 2 on the right hand side!
+
+    default: {
+      Result constant_operand(value);
+      if (reversed) {
+        LikelySmiBinaryOperation(op, &constant_operand, operand,
+                                 overwrite_mode);
+      } else {
+        LikelySmiBinaryOperation(op, operand, &constant_operand,
+                                 overwrite_mode);
+      }
+      break;
+    }
+  }
+  ASSERT(!operand->is_valid());
+}
+
+
+void CodeGenerator::Comparison(Condition cc,
+                               bool strict,
+                               ControlDestination* dest) {
+  // Strict only makes sense for equality comparisons.
+  ASSERT(!strict || cc == equal);
+
+  Result left_side;
+  Result right_side;
+  // Implement '>' and '<=' by reversal to obtain ECMA-262 conversion order.
+  if (cc == greater || cc == less_equal) {
+    cc = ReverseCondition(cc);
+    left_side = frame_->Pop();
+    right_side = frame_->Pop();
+  } else {
+    right_side = frame_->Pop();
+    left_side = frame_->Pop();
+  }
+  ASSERT(cc == less || cc == equal || cc == greater_equal);
+
+  // If either side is a constant smi, optimize the comparison.
+  bool left_side_constant_smi =
+      left_side.is_constant() && left_side.handle()->IsSmi();
+  bool right_side_constant_smi =
+      right_side.is_constant() && right_side.handle()->IsSmi();
+  bool left_side_constant_null =
+      left_side.is_constant() && left_side.handle()->IsNull();
+  bool right_side_constant_null =
+      right_side.is_constant() && right_side.handle()->IsNull();
+
+  if (left_side_constant_smi || right_side_constant_smi) {
+    if (left_side_constant_smi && right_side_constant_smi) {
+      // Trivial case, comparing two constants.
+      int left_value = Smi::cast(*left_side.handle())->value();
+      int right_value = Smi::cast(*right_side.handle())->value();
+      switch (cc) {
+        case less:
+          dest->Goto(left_value < right_value);
+          break;
+        case equal:
+          dest->Goto(left_value == right_value);
+          break;
+        case greater_equal:
+          dest->Goto(left_value >= right_value);
+          break;
+        default:
+          UNREACHABLE();
+      }
+    } else {  // Only one side is a constant Smi.
+      // If left side is a constant Smi, reverse the operands.
+      // Since one side is a constant Smi, conversion order does not matter.
+      if (left_side_constant_smi) {
+        Result temp = left_side;
+        left_side = right_side;
+        right_side = temp;
+        cc = ReverseCondition(cc);
+        // This may reintroduce greater or less_equal as the value of cc.
+        // CompareStub and the inline code both support all values of cc.
+      }
+      // Implement comparison against a constant Smi, inlining the case
+      // where both sides are Smis.
+      left_side.ToRegister();
+
+      // Here we split control flow to the stub call and inlined cases
+      // before finally splitting it to the control destination.  We use
+      // a jump target and branching to duplicate the virtual frame at
+      // the first split.  We manually handle the off-frame references
+      // by reconstituting them on the non-fall-through path.
+      JumpTarget is_smi;
+      Register left_reg = left_side.reg();
+      Handle<Object> right_val = right_side.handle();
+      __ test(left_side.reg(), Immediate(kSmiTagMask));
+      is_smi.Branch(zero, taken);
+
+      // Setup and call the compare stub.
+      CompareStub stub(cc, strict);
+      Result result = frame_->CallStub(&stub, &left_side, &right_side);
+      result.ToRegister();
+      __ cmp(result.reg(), 0);
+      result.Unuse();
+      dest->true_target()->Branch(cc);
+      dest->false_target()->Jump();
+
+      is_smi.Bind();
+      left_side = Result(left_reg);
+      right_side = Result(right_val);
+      // Test smi equality and comparison by signed int comparison.
+      if (IsUnsafeSmi(right_side.handle())) {
+        right_side.ToRegister();
+        __ cmp(left_side.reg(), Operand(right_side.reg()));
+      } else {
+        __ cmp(Operand(left_side.reg()), Immediate(right_side.handle()));
+      }
+      left_side.Unuse();
+      right_side.Unuse();
+      dest->Split(cc);
+    }
+  } else if (cc == equal &&
+             (left_side_constant_null || right_side_constant_null)) {
+    // To make null checks efficient, we check if either the left side or
+    // the right side is the constant 'null'.
+    // If so, we optimize the code by inlining a null check instead of
+    // calling the (very) general runtime routine for checking equality.
+    Result operand = left_side_constant_null ? right_side : left_side;
+    right_side.Unuse();
+    left_side.Unuse();
+    operand.ToRegister();
+    __ cmp(operand.reg(), Factory::null_value());
+    if (strict) {
+      operand.Unuse();
+      dest->Split(equal);
+    } else {
+      // The 'null' value is only equal to 'undefined' if using non-strict
+      // comparisons.
+      dest->true_target()->Branch(equal);
+      __ cmp(operand.reg(), Factory::undefined_value());
+      dest->true_target()->Branch(equal);
+      __ test(operand.reg(), Immediate(kSmiTagMask));
+      dest->false_target()->Branch(equal);
+
+      // It can be an undetectable object.
+      // Use a scratch register in preference to spilling operand.reg().
+      Result temp = allocator()->Allocate();
+      ASSERT(temp.is_valid());
+      __ mov(temp.reg(),
+             FieldOperand(operand.reg(), HeapObject::kMapOffset));
+      __ movzx_b(temp.reg(),
+                 FieldOperand(temp.reg(), Map::kBitFieldOffset));
+      __ test(temp.reg(), Immediate(1 << Map::kIsUndetectable));
+      temp.Unuse();
+      operand.Unuse();
+      dest->Split(not_zero);
+    }
+  } else {  // Neither side is a constant Smi or null.
+    // If either side is a non-smi constant, skip the smi check.
+    bool known_non_smi =
+        (left_side.is_constant() && !left_side.handle()->IsSmi()) ||
+        (right_side.is_constant() && !right_side.handle()->IsSmi());
+    left_side.ToRegister();
+    right_side.ToRegister();
+
+    if (known_non_smi) {
+      // When non-smi, call out to the compare stub.
+      CompareStub stub(cc, strict);
+      Result answer = frame_->CallStub(&stub, &left_side, &right_side);
+      if (cc == equal) {
+        __ test(answer.reg(), Operand(answer.reg()));
+      } else {
+        __ cmp(answer.reg(), 0);
+      }
+      answer.Unuse();
+      dest->Split(cc);
+    } else {
+      // Here we split control flow to the stub call and inlined cases
+      // before finally splitting it to the control destination.  We use
+      // a jump target and branching to duplicate the virtual frame at
+      // the first split.  We manually handle the off-frame references
+      // by reconstituting them on the non-fall-through path.
+      JumpTarget is_smi;
+      Register left_reg = left_side.reg();
+      Register right_reg = right_side.reg();
+
+      Result temp = allocator_->Allocate();
+      ASSERT(temp.is_valid());
+      __ mov(temp.reg(), left_side.reg());
+      __ or_(temp.reg(), Operand(right_side.reg()));
+      __ test(temp.reg(), Immediate(kSmiTagMask));
+      temp.Unuse();
+      is_smi.Branch(zero, taken);
+      // When non-smi, call out to the compare stub.
+      CompareStub stub(cc, strict);
+      Result answer = frame_->CallStub(&stub, &left_side, &right_side);
+      if (cc == equal) {
+        __ test(answer.reg(), Operand(answer.reg()));
+      } else {
+        __ cmp(answer.reg(), 0);
+      }
+      answer.Unuse();
+      dest->true_target()->Branch(cc);
+      dest->false_target()->Jump();
+
+      is_smi.Bind();
+      left_side = Result(left_reg);
+      right_side = Result(right_reg);
+      __ cmp(left_side.reg(), Operand(right_side.reg()));
+      right_side.Unuse();
+      left_side.Unuse();
+      dest->Split(cc);
+    }
+  }
+}
+
+
+class CallFunctionStub: public CodeStub {
+ public:
+  CallFunctionStub(int argc, InLoopFlag in_loop)
+      : argc_(argc), in_loop_(in_loop) { }
+
+  void Generate(MacroAssembler* masm);
+
+ private:
+  int argc_;
+  InLoopFlag in_loop_;
+
+#ifdef DEBUG
+  void Print() { PrintF("CallFunctionStub (args %d)\n", argc_); }
+#endif
+
+  Major MajorKey() { return CallFunction; }
+  int MinorKey() { return argc_; }
+  InLoopFlag InLoop() { return in_loop_; }
+};
+
+
+// Call the function just below TOS on the stack with the given
+// arguments. The receiver is the TOS.
+void CodeGenerator::CallWithArguments(ZoneList<Expression*>* args,
+                                      int position) {
+  // Push the arguments ("left-to-right") on the stack.
+  int arg_count = args->length();
+  for (int i = 0; i < arg_count; i++) {
+    Load(args->at(i));
+  }
+
+  // Record the position for debugging purposes.
+  CodeForSourcePosition(position);
+
+  // Use the shared code stub to call the function.
+  InLoopFlag in_loop = loop_nesting() > 0 ? IN_LOOP : NOT_IN_LOOP;
+  CallFunctionStub call_function(arg_count, in_loop);
+  Result answer = frame_->CallStub(&call_function, arg_count + 1);
+  // Restore context and replace function on the stack with the
+  // result of the stub invocation.
+  frame_->RestoreContextRegister();
+  frame_->SetElementAt(0, &answer);
+}
+
+
+void CodeGenerator::CallApplyLazy(Property* apply,
+                                  Expression* receiver,
+                                  VariableProxy* arguments,
+                                  int position) {
+  ASSERT(ArgumentsMode() == LAZY_ARGUMENTS_ALLOCATION);
+  ASSERT(arguments->IsArguments());
+
+  JumpTarget slow, done;
+
+  // Load the apply function onto the stack. This will usually
+  // give us a megamorphic load site. Not super, but it works.
+  Reference ref(this, apply);
+  ref.GetValue(NOT_INSIDE_TYPEOF);
+  ASSERT(ref.type() == Reference::NAMED);
+
+  // Load the receiver and the existing arguments object onto the
+  // expression stack. Avoid allocating the arguments object here.
+  Load(receiver);
+  LoadFromSlot(scope_->arguments()->var()->slot(), NOT_INSIDE_TYPEOF);
+
+  // Emit the source position information after having loaded the
+  // receiver and the arguments.
+  CodeForSourcePosition(position);
+
+  // Check if the arguments object has been lazily allocated
+  // already. If so, just use that instead of copying the arguments
+  // from the stack. This also deals with cases where a local variable
+  // named 'arguments' has been introduced.
+  frame_->Dup();
+  Result probe = frame_->Pop();
+  bool try_lazy = true;
+  if (probe.is_constant()) {
+    try_lazy = probe.handle()->IsTheHole();
+  } else {
+    __ cmp(Operand(probe.reg()), Immediate(Factory::the_hole_value()));
+    probe.Unuse();
+    slow.Branch(not_equal);
+  }
+
+  if (try_lazy) {
+    JumpTarget build_args;
+
+    // Get rid of the arguments object probe.
+    frame_->Drop();
+
+    // Before messing with the execution stack, we sync all
+    // elements. This is bound to happen anyway because we're
+    // about to call a function.
+    frame_->SyncRange(0, frame_->element_count() - 1);
+
+    // Check that the receiver really is a JavaScript object.
+    { frame_->PushElementAt(0);
+      Result receiver = frame_->Pop();
+      receiver.ToRegister();
+      __ test(receiver.reg(), Immediate(kSmiTagMask));
+      build_args.Branch(zero);
+      Result tmp = allocator_->Allocate();
+      // We allow all JSObjects including JSFunctions.  As long as
+      // JS_FUNCTION_TYPE is the last instance type and it is right
+      // after LAST_JS_OBJECT_TYPE, we do not have to check the upper
+      // bound.
+      ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
+      ASSERT(JS_FUNCTION_TYPE == LAST_JS_OBJECT_TYPE + 1);
+      __ CmpObjectType(receiver.reg(), FIRST_JS_OBJECT_TYPE, tmp.reg());
+      build_args.Branch(less);
+    }
+
+    // Verify that we're invoking Function.prototype.apply.
+    { frame_->PushElementAt(1);
+      Result apply = frame_->Pop();
+      apply.ToRegister();
+      __ test(apply.reg(), Immediate(kSmiTagMask));
+      build_args.Branch(zero);
+      Result tmp = allocator_->Allocate();
+      __ CmpObjectType(apply.reg(), JS_FUNCTION_TYPE, tmp.reg());
+      build_args.Branch(not_equal);
+      __ mov(tmp.reg(),
+             FieldOperand(apply.reg(), JSFunction::kSharedFunctionInfoOffset));
+      Handle<Code> apply_code(Builtins::builtin(Builtins::FunctionApply));
+      __ cmp(FieldOperand(tmp.reg(), SharedFunctionInfo::kCodeOffset),
+             Immediate(apply_code));
+      build_args.Branch(not_equal);
+    }
+
+    // Get the function receiver from the stack. Check that it
+    // really is a function.
+    __ mov(edi, Operand(esp, 2 * kPointerSize));
+    __ test(edi, Immediate(kSmiTagMask));
+    build_args.Branch(zero);
+    __ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
+    build_args.Branch(not_equal);
+
+    // Copy the arguments to this function possibly from the
+    // adaptor frame below it.
+    Label invoke, adapted;
+    __ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
+    __ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
+    __ cmp(Operand(ecx),
+           Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+    __ j(equal, &adapted);
+
+    // No arguments adaptor frame. Copy fixed number of arguments.
+    __ mov(eax, Immediate(scope_->num_parameters()));
+    for (int i = 0; i < scope_->num_parameters(); i++) {
+      __ push(frame_->ParameterAt(i));
+    }
+    __ jmp(&invoke);
+
+    // Arguments adaptor frame present. Copy arguments from there, but
+    // avoid copying too many arguments to avoid stack overflows.
+    __ bind(&adapted);
+    static const uint32_t kArgumentsLimit = 1 * KB;
+    __ mov(eax, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
+    __ shr(eax, kSmiTagSize);
+    __ mov(ecx, Operand(eax));
+    __ cmp(eax, kArgumentsLimit);
+    build_args.Branch(above);
+
+    // Loop through the arguments pushing them onto the execution
+    // stack. We don't inform the virtual frame of the push, so we don't
+    // have to worry about getting rid of the elements from the virtual
+    // frame.
+    Label loop;
+    __ bind(&loop);
+    __ test(ecx, Operand(ecx));
+    __ j(zero, &invoke);
+    __ push(Operand(edx, ecx, times_4, 1 * kPointerSize));
+    __ dec(ecx);
+    __ jmp(&loop);
+
+    // Invoke the function. The virtual frame knows about the receiver
+    // so make sure to forget that explicitly.
+    __ bind(&invoke);
+    ParameterCount actual(eax);
+    __ InvokeFunction(edi, actual, CALL_FUNCTION);
+    frame_->Forget(1);
+    Result result = allocator()->Allocate(eax);
+    frame_->SetElementAt(0, &result);
+    done.Jump();
+
+    // Slow-case: Allocate the arguments object since we know it isn't
+    // there, and fall-through to the slow-case where we call
+    // Function.prototype.apply.
+    build_args.Bind();
+    Result arguments_object = StoreArgumentsObject(false);
+    frame_->Push(&arguments_object);
+    slow.Bind();
+  }
+
+  // Flip the apply function and the function to call on the stack, so
+  // the function looks like the receiver of the apply call. This way,
+  // the generic Function.prototype.apply implementation can deal with
+  // the call like it usually does.
+  Result a2 = frame_->Pop();
+  Result a1 = frame_->Pop();
+  Result ap = frame_->Pop();
+  Result fn = frame_->Pop();
+  frame_->Push(&ap);
+  frame_->Push(&fn);
+  frame_->Push(&a1);
+  frame_->Push(&a2);
+  CallFunctionStub call_function(2, NOT_IN_LOOP);
+  Result res = frame_->CallStub(&call_function, 3);
+  frame_->Push(&res);
+
+  // All done. Restore context register after call.
+  if (try_lazy) done.Bind();
+  frame_->RestoreContextRegister();
+}
+
+
+class DeferredStackCheck: public DeferredCode {
+ public:
+  DeferredStackCheck() {
+    set_comment("[ DeferredStackCheck");
+  }
+
+  virtual void Generate();
+};
+
+
+void DeferredStackCheck::Generate() {
+  StackCheckStub stub;
+  __ CallStub(&stub);
+}
+
+
+void CodeGenerator::CheckStack() {
+  if (FLAG_check_stack) {
+    DeferredStackCheck* deferred = new DeferredStackCheck;
+    ExternalReference stack_guard_limit =
+        ExternalReference::address_of_stack_guard_limit();
+    __ cmp(esp, Operand::StaticVariable(stack_guard_limit));
+    deferred->Branch(below);
+    deferred->BindExit();
+  }
+}
+
+
+void CodeGenerator::VisitAndSpill(Statement* statement) {
+  ASSERT(in_spilled_code());
+  set_in_spilled_code(false);
+  Visit(statement);
+  if (frame_ != NULL) {
+    frame_->SpillAll();
+  }
+  set_in_spilled_code(true);
+}
+
+
+void CodeGenerator::VisitStatementsAndSpill(ZoneList<Statement*>* statements) {
+  ASSERT(in_spilled_code());
+  set_in_spilled_code(false);
+  VisitStatements(statements);
+  if (frame_ != NULL) {
+    frame_->SpillAll();
+  }
+  set_in_spilled_code(true);
+}
+
+
+void CodeGenerator::VisitStatements(ZoneList<Statement*>* statements) {
+  ASSERT(!in_spilled_code());
+  for (int i = 0; has_valid_frame() && i < statements->length(); i++) {
+    Visit(statements->at(i));
+  }
+}
+
+
+void CodeGenerator::VisitBlock(Block* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ Block");
+  CodeForStatementPosition(node);
+  node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
+  VisitStatements(node->statements());
+  if (node->break_target()->is_linked()) {
+    node->break_target()->Bind();
+  }
+  node->break_target()->Unuse();
+}
+
+
+void CodeGenerator::DeclareGlobals(Handle<FixedArray> pairs) {
+  // Call the runtime to declare the globals.  The inevitable call
+  // will sync frame elements to memory anyway, so we do it eagerly to
+  // allow us to push the arguments directly into place.
+  frame_->SyncRange(0, frame_->element_count() - 1);
+
+  frame_->EmitPush(Immediate(pairs));
+  frame_->EmitPush(esi);  // The context is the second argument.
+  frame_->EmitPush(Immediate(Smi::FromInt(is_eval() ? 1 : 0)));
+  Result ignored = frame_->CallRuntime(Runtime::kDeclareGlobals, 3);
+  // Return value is ignored.
+}
+
+
+void CodeGenerator::VisitDeclaration(Declaration* node) {
+  Comment cmnt(masm_, "[ Declaration");
+  Variable* var = node->proxy()->var();
+  ASSERT(var != NULL);  // must have been resolved
+  Slot* slot = var->slot();
+
+  // If it was not possible to allocate the variable at compile time,
+  // we need to "declare" it at runtime to make sure it actually
+  // exists in the local context.
+  if (slot != NULL && slot->type() == Slot::LOOKUP) {
+    // Variables with a "LOOKUP" slot were introduced as non-locals
+    // during variable resolution and must have mode DYNAMIC.
+    ASSERT(var->is_dynamic());
+    // For now, just do a runtime call.  Sync the virtual frame eagerly
+    // so we can simply push the arguments into place.
+    frame_->SyncRange(0, frame_->element_count() - 1);
+    frame_->EmitPush(esi);
+    frame_->EmitPush(Immediate(var->name()));
+    // Declaration nodes are always introduced in one of two modes.
+    ASSERT(node->mode() == Variable::VAR || node->mode() == Variable::CONST);
+    PropertyAttributes attr = node->mode() == Variable::VAR ? NONE : READ_ONLY;
+    frame_->EmitPush(Immediate(Smi::FromInt(attr)));
+    // Push initial value, if any.
+    // Note: For variables we must not push an initial value (such as
+    // 'undefined') because we may have a (legal) redeclaration and we
+    // must not destroy the current value.
+    if (node->mode() == Variable::CONST) {
+      frame_->EmitPush(Immediate(Factory::the_hole_value()));
+    } else if (node->fun() != NULL) {
+      Load(node->fun());
+    } else {
+      frame_->EmitPush(Immediate(Smi::FromInt(0)));  // no initial value!
+    }
+    Result ignored = frame_->CallRuntime(Runtime::kDeclareContextSlot, 4);
+    // Ignore the return value (declarations are statements).
+    return;
+  }
+
+  ASSERT(!var->is_global());
+
+  // If we have a function or a constant, we need to initialize the variable.
+  Expression* val = NULL;
+  if (node->mode() == Variable::CONST) {
+    val = new Literal(Factory::the_hole_value());
+  } else {
+    val = node->fun();  // NULL if we don't have a function
+  }
+
+  if (val != NULL) {
+    {
+      // Set the initial value.
+      Reference target(this, node->proxy());
+      Load(val);
+      target.SetValue(NOT_CONST_INIT);
+      // The reference is removed from the stack (preserving TOS) when
+      // it goes out of scope.
+    }
+    // Get rid of the assigned value (declarations are statements).
+    frame_->Drop();
+  }
+}
+
+
+void CodeGenerator::VisitExpressionStatement(ExpressionStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ ExpressionStatement");
+  CodeForStatementPosition(node);
+  Expression* expression = node->expression();
+  expression->MarkAsStatement();
+  Load(expression);
+  // Remove the lingering expression result from the top of stack.
+  frame_->Drop();
+}
+
+
+void CodeGenerator::VisitEmptyStatement(EmptyStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "// EmptyStatement");
+  CodeForStatementPosition(node);
+  // nothing to do
+}
+
+
+void CodeGenerator::VisitIfStatement(IfStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ IfStatement");
+  // Generate different code depending on which parts of the if statement
+  // are present or not.
+  bool has_then_stm = node->HasThenStatement();
+  bool has_else_stm = node->HasElseStatement();
+
+  CodeForStatementPosition(node);
+  JumpTarget exit;
+  if (has_then_stm && has_else_stm) {
+    JumpTarget then;
+    JumpTarget else_;
+    ControlDestination dest(&then, &else_, true);
+    LoadCondition(node->condition(), NOT_INSIDE_TYPEOF, &dest, true);
+
+    if (dest.false_was_fall_through()) {
+      // The else target was bound, so we compile the else part first.
+      Visit(node->else_statement());
+
+      // We may have dangling jumps to the then part.
+      if (then.is_linked()) {
+        if (has_valid_frame()) exit.Jump();
+        then.Bind();
+        Visit(node->then_statement());
+      }
+    } else {
+      // The then target was bound, so we compile the then part first.
+      Visit(node->then_statement());
+
+      if (else_.is_linked()) {
+        if (has_valid_frame()) exit.Jump();
+        else_.Bind();
+        Visit(node->else_statement());
+      }
+    }
+
+  } else if (has_then_stm) {
+    ASSERT(!has_else_stm);
+    JumpTarget then;
+    ControlDestination dest(&then, &exit, true);
+    LoadCondition(node->condition(), NOT_INSIDE_TYPEOF, &dest, true);
+
+    if (dest.false_was_fall_through()) {
+      // The exit label was bound.  We may have dangling jumps to the
+      // then part.
+      if (then.is_linked()) {
+        exit.Unuse();
+        exit.Jump();
+        then.Bind();
+        Visit(node->then_statement());
+      }
+    } else {
+      // The then label was bound.
+      Visit(node->then_statement());
+    }
+
+  } else if (has_else_stm) {
+    ASSERT(!has_then_stm);
+    JumpTarget else_;
+    ControlDestination dest(&exit, &else_, false);
+    LoadCondition(node->condition(), NOT_INSIDE_TYPEOF, &dest, true);
+
+    if (dest.true_was_fall_through()) {
+      // The exit label was bound.  We may have dangling jumps to the
+      // else part.
+      if (else_.is_linked()) {
+        exit.Unuse();
+        exit.Jump();
+        else_.Bind();
+        Visit(node->else_statement());
+      }
+    } else {
+      // The else label was bound.
+      Visit(node->else_statement());
+    }
+
+  } else {
+    ASSERT(!has_then_stm && !has_else_stm);
+    // We only care about the condition's side effects (not its value
+    // or control flow effect).  LoadCondition is called without
+    // forcing control flow.
+    ControlDestination dest(&exit, &exit, true);
+    LoadCondition(node->condition(), NOT_INSIDE_TYPEOF, &dest, false);
+    if (!dest.is_used()) {
+      // We got a value on the frame rather than (or in addition to)
+      // control flow.
+      frame_->Drop();
+    }
+  }
+
+  if (exit.is_linked()) {
+    exit.Bind();
+  }
+}
+
+
+void CodeGenerator::VisitContinueStatement(ContinueStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ ContinueStatement");
+  CodeForStatementPosition(node);
+  node->target()->continue_target()->Jump();
+}
+
+
+void CodeGenerator::VisitBreakStatement(BreakStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ BreakStatement");
+  CodeForStatementPosition(node);
+  node->target()->break_target()->Jump();
+}
+
+
+void CodeGenerator::VisitReturnStatement(ReturnStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ ReturnStatement");
+
+  CodeForStatementPosition(node);
+  Load(node->expression());
+  Result return_value = frame_->Pop();
+  if (function_return_is_shadowed_) {
+    function_return_.Jump(&return_value);
+  } else {
+    frame_->PrepareForReturn();
+    if (function_return_.is_bound()) {
+      // If the function return label is already bound we reuse the
+      // code by jumping to the return site.
+      function_return_.Jump(&return_value);
+    } else {
+      function_return_.Bind(&return_value);
+      GenerateReturnSequence(&return_value);
+    }
+  }
+}
+
+
+void CodeGenerator::GenerateReturnSequence(Result* return_value) {
+  // The return value is a live (but not currently reference counted)
+  // reference to eax.  This is safe because the current frame does not
+  // contain a reference to eax (it is prepared for the return by spilling
+  // all registers).
+  if (FLAG_trace) {
+    frame_->Push(return_value);
+    *return_value = frame_->CallRuntime(Runtime::kTraceExit, 1);
+  }
+  return_value->ToRegister(eax);
+
+  // Add a label for checking the size of the code used for returning.
+  Label check_exit_codesize;
+  masm_->bind(&check_exit_codesize);
+
+  // Leave the frame and return popping the arguments and the
+  // receiver.
+  frame_->Exit();
+  masm_->ret((scope_->num_parameters() + 1) * kPointerSize);
+  DeleteFrame();
+
+#ifdef ENABLE_DEBUGGER_SUPPORT
+  // Check that the size of the code used for returning matches what is
+  // expected by the debugger.
+  ASSERT_EQ(Debug::kIa32JSReturnSequenceLength,
+            masm_->SizeOfCodeGeneratedSince(&check_exit_codesize));
+#endif
+}
+
+
+void CodeGenerator::VisitWithEnterStatement(WithEnterStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ WithEnterStatement");
+  CodeForStatementPosition(node);
+  Load(node->expression());
+  Result context;
+  if (node->is_catch_block()) {
+    context = frame_->CallRuntime(Runtime::kPushCatchContext, 1);
+  } else {
+    context = frame_->CallRuntime(Runtime::kPushContext, 1);
+  }
+
+  // Update context local.
+  frame_->SaveContextRegister();
+
+  // Verify that the runtime call result and esi agree.
+  if (FLAG_debug_code) {
+    __ cmp(context.reg(), Operand(esi));
+    __ Assert(equal, "Runtime::NewContext should end up in esi");
+  }
+}
+
+
+void CodeGenerator::VisitWithExitStatement(WithExitStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ WithExitStatement");
+  CodeForStatementPosition(node);
+  // Pop context.
+  __ mov(esi, ContextOperand(esi, Context::PREVIOUS_INDEX));
+  // Update context local.
+  frame_->SaveContextRegister();
+}
+
+
+void CodeGenerator::VisitSwitchStatement(SwitchStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ SwitchStatement");
+  CodeForStatementPosition(node);
+  node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
+
+  // Compile the switch value.
+  Load(node->tag());
+
+  ZoneList<CaseClause*>* cases = node->cases();
+  int length = cases->length();
+  CaseClause* default_clause = NULL;
+
+  JumpTarget next_test;
+  // Compile the case label expressions and comparisons.  Exit early
+  // if a comparison is unconditionally true.  The target next_test is
+  // bound before the loop in order to indicate control flow to the
+  // first comparison.
+  next_test.Bind();
+  for (int i = 0; i < length && !next_test.is_unused(); i++) {
+    CaseClause* clause = cases->at(i);
+    // The default is not a test, but remember it for later.
+    if (clause->is_default()) {
+      default_clause = clause;
+      continue;
+    }
+
+    Comment cmnt(masm_, "[ Case comparison");
+    // We recycle the same target next_test for each test.  Bind it if
+    // the previous test has not done so and then unuse it for the
+    // loop.
+    if (next_test.is_linked()) {
+      next_test.Bind();
+    }
+    next_test.Unuse();
+
+    // Duplicate the switch value.
+    frame_->Dup();
+
+    // Compile the label expression.
+    Load(clause->label());
+
+    // Compare and branch to the body if true or the next test if
+    // false.  Prefer the next test as a fall through.
+    ControlDestination dest(clause->body_target(), &next_test, false);
+    Comparison(equal, true, &dest);
+
+    // If the comparison fell through to the true target, jump to the
+    // actual body.
+    if (dest.true_was_fall_through()) {
+      clause->body_target()->Unuse();
+      clause->body_target()->Jump();
+    }
+  }
+
+  // If there was control flow to a next test from the last one
+  // compiled, compile a jump to the default or break target.
+  if (!next_test.is_unused()) {
+    if (next_test.is_linked()) {
+      next_test.Bind();
+    }
+    // Drop the switch value.
+    frame_->Drop();
+    if (default_clause != NULL) {
+      default_clause->body_target()->Jump();
+    } else {
+      node->break_target()->Jump();
+    }
+  }
+
+
+  // The last instruction emitted was a jump, either to the default
+  // clause or the break target, or else to a case body from the loop
+  // that compiles the tests.
+  ASSERT(!has_valid_frame());
+  // Compile case bodies as needed.
+  for (int i = 0; i < length; i++) {
+    CaseClause* clause = cases->at(i);
+
+    // There are two ways to reach the body: from the corresponding
+    // test or as the fall through of the previous body.
+    if (clause->body_target()->is_linked() || has_valid_frame()) {
+      if (clause->body_target()->is_linked()) {
+        if (has_valid_frame()) {
+          // If we have both a jump to the test and a fall through, put
+          // a jump on the fall through path to avoid the dropping of
+          // the switch value on the test path.  The exception is the
+          // default which has already had the switch value dropped.
+          if (clause->is_default()) {
+            clause->body_target()->Bind();
+          } else {
+            JumpTarget body;
+            body.Jump();
+            clause->body_target()->Bind();
+            frame_->Drop();
+            body.Bind();
+          }
+        } else {
+          // No fall through to worry about.
+          clause->body_target()->Bind();
+          if (!clause->is_default()) {
+            frame_->Drop();
+          }
+        }
+      } else {
+        // Otherwise, we have only fall through.
+        ASSERT(has_valid_frame());
+      }
+
+      // We are now prepared to compile the body.
+      Comment cmnt(masm_, "[ Case body");
+      VisitStatements(clause->statements());
+    }
+    clause->body_target()->Unuse();
+  }
+
+  // We may not have a valid frame here so bind the break target only
+  // if needed.
+  if (node->break_target()->is_linked()) {
+    node->break_target()->Bind();
+  }
+  node->break_target()->Unuse();
+}
+
+
+void CodeGenerator::VisitLoopStatement(LoopStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ LoopStatement");
+  CodeForStatementPosition(node);
+  node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
+
+  // Simple condition analysis.  ALWAYS_TRUE and ALWAYS_FALSE represent a
+  // known result for the test expression, with no side effects.
+  enum { ALWAYS_TRUE, ALWAYS_FALSE, DONT_KNOW } info = DONT_KNOW;
+  if (node->cond() == NULL) {
+    ASSERT(node->type() == LoopStatement::FOR_LOOP);
+    info = ALWAYS_TRUE;
+  } else {
+    Literal* lit = node->cond()->AsLiteral();
+    if (lit != NULL) {
+      if (lit->IsTrue()) {
+        info = ALWAYS_TRUE;
+      } else if (lit->IsFalse()) {
+        info = ALWAYS_FALSE;
+      }
+    }
+  }
+
+  switch (node->type()) {
+    case LoopStatement::DO_LOOP: {
+      JumpTarget body(JumpTarget::BIDIRECTIONAL);
+      IncrementLoopNesting();
+
+      // Label the top of the loop for the backward jump if necessary.
+      if (info == ALWAYS_TRUE) {
+        // Use the continue target.
+        node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
+        node->continue_target()->Bind();
+      } else if (info == ALWAYS_FALSE) {
+        // No need to label it.
+        node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
+      } else {
+        // Continue is the test, so use the backward body target.
+        ASSERT(info == DONT_KNOW);
+        node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
+        body.Bind();
+      }
+
+      CheckStack();  // TODO(1222600): ignore if body contains calls.
+      Visit(node->body());
+
+      // Compile the test.
+      if (info == ALWAYS_TRUE) {
+        // If control flow can fall off the end of the body, jump back
+        // to the top and bind the break target at the exit.
+        if (has_valid_frame()) {
+          node->continue_target()->Jump();
+        }
+        if (node->break_target()->is_linked()) {
+          node->break_target()->Bind();
+        }
+
+      } else if (info == ALWAYS_FALSE) {
+        // We may have had continues or breaks in the body.
+        if (node->continue_target()->is_linked()) {
+          node->continue_target()->Bind();
+        }
+        if (node->break_target()->is_linked()) {
+          node->break_target()->Bind();
+        }
+
+      } else {
+        ASSERT(info == DONT_KNOW);
+        // We have to compile the test expression if it can be reached by
+        // control flow falling out of the body or via continue.
+        if (node->continue_target()->is_linked()) {
+          node->continue_target()->Bind();
+        }
+        if (has_valid_frame()) {
+          ControlDestination dest(&body, node->break_target(), false);
+          LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &dest, true);
+        }
+        if (node->break_target()->is_linked()) {
+          node->break_target()->Bind();
+        }
+      }
+      break;
+    }
+
+    case LoopStatement::WHILE_LOOP: {
+      // Do not duplicate conditions that may have function literal
+      // subexpressions.  This can cause us to compile the function
+      // literal twice.
+      bool test_at_bottom = !node->may_have_function_literal();
+
+      IncrementLoopNesting();
+
+      // If the condition is always false and has no side effects, we
+      // do not need to compile anything.
+      if (info == ALWAYS_FALSE) break;
+
+      JumpTarget body;
+      if (test_at_bottom) {
+        body.set_direction(JumpTarget::BIDIRECTIONAL);
+      }
+
+      // Based on the condition analysis, compile the test as necessary.
+      if (info == ALWAYS_TRUE) {
+        // We will not compile the test expression.  Label the top of
+        // the loop with the continue target.
+        node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
+        node->continue_target()->Bind();
+      } else {
+        ASSERT(info == DONT_KNOW);  // ALWAYS_FALSE cannot reach here.
+        if (test_at_bottom) {
+          // Continue is the test at the bottom, no need to label the
+          // test at the top.  The body is a backward target.
+          node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
+        } else {
+          // Label the test at the top as the continue target.  The
+          // body is a forward-only target.
+          node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
+          node->continue_target()->Bind();
+        }
+        // Compile the test with the body as the true target and
+        // preferred fall-through and with the break target as the
+        // false target.
+        ControlDestination dest(&body, node->break_target(), true);
+        LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &dest, true);
+
+        if (dest.false_was_fall_through()) {
+          // If we got the break target as fall-through, the test may
+          // have been unconditionally false (if there are no jumps to
+          // the body).
+          if (!body.is_linked()) break;
+
+          // Otherwise, jump around the body on the fall through and
+          // then bind the body target.
+          node->break_target()->Unuse();
+          node->break_target()->Jump();
+          body.Bind();
+        }
+      }
+
+      CheckStack();  // TODO(1222600): ignore if body contains calls.
+      Visit(node->body());
+
+      // Based on the condition analysis, compile the backward jump as
+      // necessary.
+      if (info == ALWAYS_TRUE) {
+        // The loop body has been labeled with the continue target.
+        if (has_valid_frame()) {
+          node->continue_target()->Jump();
+        }
+      } else {
+        ASSERT(info == DONT_KNOW);  // ALWAYS_FALSE cannot reach here.
+        if (test_at_bottom) {
+          // If we have chosen to recompile the test at the bottom,
+          // then it is the continue target.
+          if (node->continue_target()->is_linked()) {
+            node->continue_target()->Bind();
+          }
+          if (has_valid_frame()) {
+            // The break target is the fall-through (body is a backward
+            // jump from here and thus an invalid fall-through).
+            ControlDestination dest(&body, node->break_target(), false);
+            LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &dest, true);
+          }
+        } else {
+          // If we have chosen not to recompile the test at the
+          // bottom, jump back to the one at the top.
+          if (has_valid_frame()) {
+            node->continue_target()->Jump();
+          }
+        }
+      }
+
+      // The break target may be already bound (by the condition), or
+      // there may not be a valid frame.  Bind it only if needed.
+      if (node->break_target()->is_linked()) {
+        node->break_target()->Bind();
+      }
+      break;
+    }
+
+    case LoopStatement::FOR_LOOP: {
+      // Do not duplicate conditions that may have function literal
+      // subexpressions.  This can cause us to compile the function
+      // literal twice.
+      bool test_at_bottom = !node->may_have_function_literal();
+
+      // Compile the init expression if present.
+      if (node->init() != NULL) {
+        Visit(node->init());
+      }
+
+      IncrementLoopNesting();
+
+      // If the condition is always false and has no side effects, we
+      // do not need to compile anything else.
+      if (info == ALWAYS_FALSE) break;
+
+      // Target for backward edge if no test at the bottom, otherwise
+      // unused.
+      JumpTarget loop(JumpTarget::BIDIRECTIONAL);
+
+      // Target for backward edge if there is a test at the bottom,
+      // otherwise used as target for test at the top.
+      JumpTarget body;
+      if (test_at_bottom) {
+        body.set_direction(JumpTarget::BIDIRECTIONAL);
+      }
+
+      // Based on the condition analysis, compile the test as necessary.
+      if (info == ALWAYS_TRUE) {
+        // We will not compile the test expression.  Label the top of
+        // the loop.
+        if (node->next() == NULL) {
+          // Use the continue target if there is no update expression.
+          node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
+          node->continue_target()->Bind();
+        } else {
+          // Otherwise use the backward loop target.
+          node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
+          loop.Bind();
+        }
+      } else {
+        ASSERT(info == DONT_KNOW);
+        if (test_at_bottom) {
+          // Continue is either the update expression or the test at
+          // the bottom, no need to label the test at the top.
+          node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
+        } else if (node->next() == NULL) {
+          // We are not recompiling the test at the bottom and there
+          // is no update expression.
+          node->continue_target()->set_direction(JumpTarget::BIDIRECTIONAL);
+          node->continue_target()->Bind();
+        } else {
+          // We are not recompiling the test at the bottom and there
+          // is an update expression.
+          node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
+          loop.Bind();
+        }
+
+        // Compile the test with the body as the true target and
+        // preferred fall-through and with the break target as the
+        // false target.
+        ControlDestination dest(&body, node->break_target(), true);
+        LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &dest, true);
+
+        if (dest.false_was_fall_through()) {
+          // If we got the break target as fall-through, the test may
+          // have been unconditionally false (if there are no jumps to
+          // the body).
+          if (!body.is_linked()) break;
+
+          // Otherwise, jump around the body on the fall through and
+          // then bind the body target.
+          node->break_target()->Unuse();
+          node->break_target()->Jump();
+          body.Bind();
+        }
+      }
+
+      CheckStack();  // TODO(1222600): ignore if body contains calls.
+      Visit(node->body());
+
+      // If there is an update expression, compile it if necessary.
+      if (node->next() != NULL) {
+        if (node->continue_target()->is_linked()) {
+          node->continue_target()->Bind();
+        }
+
+        // Control can reach the update by falling out of the body or
+        // by a continue.
+        if (has_valid_frame()) {
+          // Record the source position of the statement as this code
+          // which is after the code for the body actually belongs to
+          // the loop statement and not the body.
+          CodeForStatementPosition(node);
+          Visit(node->next());
+        }
+      }
+
+      // Based on the condition analysis, compile the backward jump as
+      // necessary.
+      if (info == ALWAYS_TRUE) {
+        if (has_valid_frame()) {
+          if (node->next() == NULL) {
+            node->continue_target()->Jump();
+          } else {
+            loop.Jump();
+          }
+        }
+      } else {
+        ASSERT(info == DONT_KNOW);  // ALWAYS_FALSE cannot reach here.
+        if (test_at_bottom) {
+          if (node->continue_target()->is_linked()) {
+            // We can have dangling jumps to the continue target if
+            // there was no update expression.
+            node->continue_target()->Bind();
+          }
+          // Control can reach the test at the bottom by falling out
+          // of the body, by a continue in the body, or from the
+          // update expression.
+          if (has_valid_frame()) {
+            // The break target is the fall-through (body is a
+            // backward jump from here).
+            ControlDestination dest(&body, node->break_target(), false);
+            LoadCondition(node->cond(), NOT_INSIDE_TYPEOF, &dest, true);
+          }
+        } else {
+          // Otherwise, jump back to the test at the top.
+          if (has_valid_frame()) {
+            if (node->next() == NULL) {
+              node->continue_target()->Jump();
+            } else {
+              loop.Jump();
+            }
+          }
+        }
+      }
+
+      // The break target may be already bound (by the condition), or
+      // there may not be a valid frame.  Bind it only if needed.
+      if (node->break_target()->is_linked()) {
+        node->break_target()->Bind();
+      }
+      break;
+    }
+  }
+
+  DecrementLoopNesting();
+  node->continue_target()->Unuse();
+  node->break_target()->Unuse();
+}
+
+
+void CodeGenerator::VisitForInStatement(ForInStatement* node) {
+  ASSERT(!in_spilled_code());
+  VirtualFrame::SpilledScope spilled_scope;
+  Comment cmnt(masm_, "[ ForInStatement");
+  CodeForStatementPosition(node);
+
+  JumpTarget primitive;
+  JumpTarget jsobject;
+  JumpTarget fixed_array;
+  JumpTarget entry(JumpTarget::BIDIRECTIONAL);
+  JumpTarget end_del_check;
+  JumpTarget exit;
+
+  // Get the object to enumerate over (converted to JSObject).
+  LoadAndSpill(node->enumerable());
+
+  // Both SpiderMonkey and kjs ignore null and undefined in contrast
+  // to the specification.  12.6.4 mandates a call to ToObject.
+  frame_->EmitPop(eax);
+
+  // eax: value to be iterated over
+  __ cmp(eax, Factory::undefined_value());
+  exit.Branch(equal);
+  __ cmp(eax, Factory::null_value());
+  exit.Branch(equal);
+
+  // Stack layout in body:
+  // [iteration counter (smi)] <- slot 0
+  // [length of array]         <- slot 1
+  // [FixedArray]              <- slot 2
+  // [Map or 0]                <- slot 3
+  // [Object]                  <- slot 4
+
+  // Check if enumerable is already a JSObject
+  // eax: value to be iterated over
+  __ test(eax, Immediate(kSmiTagMask));
+  primitive.Branch(zero);
+  __ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
+  __ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
+  __ cmp(ecx, FIRST_JS_OBJECT_TYPE);
+  jsobject.Branch(above_equal);
+
+  primitive.Bind();
+  frame_->EmitPush(eax);
+  frame_->InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION, 1);
+  // function call returns the value in eax, which is where we want it below
+
+  jsobject.Bind();
+  // Get the set of properties (as a FixedArray or Map).
+  // eax: value to be iterated over
+  frame_->EmitPush(eax);  // push the object being iterated over (slot 4)
+
+  frame_->EmitPush(eax);  // push the Object (slot 4) for the runtime call
+  frame_->CallRuntime(Runtime::kGetPropertyNamesFast, 1);
+
+  // If we got a Map, we can do a fast modification check.
+  // Otherwise, we got a FixedArray, and we have to do a slow check.
+  // eax: map or fixed array (result from call to
+  // Runtime::kGetPropertyNamesFast)
+  __ mov(edx, Operand(eax));
+  __ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
+  __ cmp(ecx, Factory::meta_map());
+  fixed_array.Branch(not_equal);
+
+  // Get enum cache
+  // eax: map (result from call to Runtime::kGetPropertyNamesFast)
+  __ mov(ecx, Operand(eax));
+  __ mov(ecx, FieldOperand(ecx, Map::kInstanceDescriptorsOffset));
+  // Get the bridge array held in the enumeration index field.
+  __ mov(ecx, FieldOperand(ecx, DescriptorArray::kEnumerationIndexOffset));
+  // Get the cache from the bridge array.
+  __ mov(edx, FieldOperand(ecx, DescriptorArray::kEnumCacheBridgeCacheOffset));
+
+  frame_->EmitPush(eax);  // <- slot 3
+  frame_->EmitPush(edx);  // <- slot 2
+  __ mov(eax, FieldOperand(edx, FixedArray::kLengthOffset));
+  __ shl(eax, kSmiTagSize);
+  frame_->EmitPush(eax);  // <- slot 1
+  frame_->EmitPush(Immediate(Smi::FromInt(0)));  // <- slot 0
+  entry.Jump();
+
+  fixed_array.Bind();
+  // eax: fixed array (result from call to Runtime::kGetPropertyNamesFast)
+  frame_->EmitPush(Immediate(Smi::FromInt(0)));  // <- slot 3
+  frame_->EmitPush(eax);  // <- slot 2
+
+  // Push the length of the array and the initial index onto the stack.
+  __ mov(eax, FieldOperand(eax, FixedArray::kLengthOffset));
+  __ shl(eax, kSmiTagSize);
+  frame_->EmitPush(eax);  // <- slot 1
+  frame_->EmitPush(Immediate(Smi::FromInt(0)));  // <- slot 0
+
+  // Condition.
+  entry.Bind();
+  // Grab the current frame's height for the break and continue
+  // targets only after all the state is pushed on the frame.
+  node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
+  node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
+
+  __ mov(eax, frame_->ElementAt(0));  // load the current count
+  __ cmp(eax, frame_->ElementAt(1));  // compare to the array length
+  node->break_target()->Branch(above_equal);
+
+  // Get the i'th entry of the array.
+  __ mov(edx, frame_->ElementAt(2));
+  __ mov(ebx, Operand(edx, eax, times_2,
+                      FixedArray::kHeaderSize - kHeapObjectTag));
+
+  // Get the expected map from the stack or a zero map in the
+  // permanent slow case eax: current iteration count ebx: i'th entry
+  // of the enum cache
+  __ mov(edx, frame_->ElementAt(3));
+  // Check if the expected map still matches that of the enumerable.
+  // If not, we have to filter the key.
+  // eax: current iteration count
+  // ebx: i'th entry of the enum cache
+  // edx: expected map value
+  __ mov(ecx, frame_->ElementAt(4));
+  __ mov(ecx, FieldOperand(ecx, HeapObject::kMapOffset));
+  __ cmp(ecx, Operand(edx));
+  end_del_check.Branch(equal);
+
+  // Convert the entry to a string (or null if it isn't a property anymore).
+  frame_->EmitPush(frame_->ElementAt(4));  // push enumerable
+  frame_->EmitPush(ebx);  // push entry
+  frame_->InvokeBuiltin(Builtins::FILTER_KEY, CALL_FUNCTION, 2);
+  __ mov(ebx, Operand(eax));
+
+  // If the property has been removed while iterating, we just skip it.
+  __ cmp(ebx, Factory::null_value());
+  node->continue_target()->Branch(equal);
+
+  end_del_check.Bind();
+  // Store the entry in the 'each' expression and take another spin in the
+  // loop.  edx: i'th entry of the enum cache (or string there of)
+  frame_->EmitPush(ebx);
+  { Reference each(this, node->each());
+    // Loading a reference may leave the frame in an unspilled state.
+    frame_->SpillAll();
+    if (!each.is_illegal()) {
+      if (each.size() > 0) {
+        frame_->EmitPush(frame_->ElementAt(each.size()));
+      }
+      // If the reference was to a slot we rely on the convenient property
+      // that it doesn't matter whether a value (eg, ebx pushed above) is
+      // right on top of or right underneath a zero-sized reference.
+      each.SetValue(NOT_CONST_INIT);
+      if (each.size() > 0) {
+        // It's safe to pop the value lying on top of the reference before
+        // unloading the reference itself (which preserves the top of stack,
+        // ie, now the topmost value of the non-zero sized reference), since
+        // we will discard the top of stack after unloading the reference
+        // anyway.
+        frame_->Drop();
+      }
+    }
+  }
+  // Unloading a reference may leave the frame in an unspilled state.
+  frame_->SpillAll();
+
+  // Discard the i'th entry pushed above or else the remainder of the
+  // reference, whichever is currently on top of the stack.
+  frame_->Drop();
+
+  // Body.
+  CheckStack();  // TODO(1222600): ignore if body contains calls.
+  VisitAndSpill(node->body());
+
+  // Next.  Reestablish a spilled frame in case we are coming here via
+  // a continue in the body.
+  node->continue_target()->Bind();
+  frame_->SpillAll();
+  frame_->EmitPop(eax);
+  __ add(Operand(eax), Immediate(Smi::FromInt(1)));
+  frame_->EmitPush(eax);
+  entry.Jump();
+
+  // Cleanup.  No need to spill because VirtualFrame::Drop is safe for
+  // any frame.
+  node->break_target()->Bind();
+  frame_->Drop(5);
+
+  // Exit.
+  exit.Bind();
+
+  node->continue_target()->Unuse();
+  node->break_target()->Unuse();
+}
+
+
+void CodeGenerator::VisitTryCatch(TryCatch* node) {
+  ASSERT(!in_spilled_code());
+  VirtualFrame::SpilledScope spilled_scope;
+  Comment cmnt(masm_, "[ TryCatch");
+  CodeForStatementPosition(node);
+
+  JumpTarget try_block;
+  JumpTarget exit;
+
+  try_block.Call();
+  // --- Catch block ---
+  frame_->EmitPush(eax);
+
+  // Store the caught exception in the catch variable.
+  { Reference ref(this, node->catch_var());
+    ASSERT(ref.is_slot());
+    // Load the exception to the top of the stack.  Here we make use of the
+    // convenient property that it doesn't matter whether a value is
+    // immediately on top of or underneath a zero-sized reference.
+    ref.SetValue(NOT_CONST_INIT);
+  }
+
+  // Remove the exception from the stack.
+  frame_->Drop();
+
+  VisitStatementsAndSpill(node->catch_block()->statements());
+  if (has_valid_frame()) {
+    exit.Jump();
+  }
+
+
+  // --- Try block ---
+  try_block.Bind();
+
+  frame_->PushTryHandler(TRY_CATCH_HANDLER);
+  int handler_height = frame_->height();
+
+  // Shadow the jump targets for all escapes from the try block, including
+  // returns.  During shadowing, the original target is hidden as the
+  // ShadowTarget and operations on the original actually affect the
+  // shadowing target.
+  //
+  // We should probably try to unify the escaping targets and the return
+  // target.
+  int nof_escapes = node->escaping_targets()->length();
+  List<ShadowTarget*> shadows(1 + nof_escapes);
+
+  // Add the shadow target for the function return.
+  static const int kReturnShadowIndex = 0;
+  shadows.Add(new ShadowTarget(&function_return_));
+  bool function_return_was_shadowed = function_return_is_shadowed_;
+  function_return_is_shadowed_ = true;
+  ASSERT(shadows[kReturnShadowIndex]->other_target() == &function_return_);
+
+  // Add the remaining shadow targets.
+  for (int i = 0; i < nof_escapes; i++) {
+    shadows.Add(new ShadowTarget(node->escaping_targets()->at(i)));
+  }
+
+  // Generate code for the statements in the try block.
+  VisitStatementsAndSpill(node->try_block()->statements());
+
+  // Stop the introduced shadowing and count the number of required unlinks.
+  // After shadowing stops, the original targets are unshadowed and the
+  // ShadowTargets represent the formerly shadowing targets.
+  bool has_unlinks = false;
+  for (int i = 0; i < shadows.length(); i++) {
+    shadows[i]->StopShadowing();
+    has_unlinks = has_unlinks || shadows[i]->is_linked();
+  }
+  function_return_is_shadowed_ = function_return_was_shadowed;
+
+  // Get an external reference to the handler address.
+  ExternalReference handler_address(Top::k_handler_address);
+
+  // Make sure that there's nothing left on the stack above the
+  // handler structure.
+  if (FLAG_debug_code) {
+    __ mov(eax, Operand::StaticVariable(handler_address));
+    __ cmp(esp, Operand(eax));
+    __ Assert(equal, "stack pointer should point to top handler");
+  }
+
+  // If we can fall off the end of the try block, unlink from try chain.
+  if (has_valid_frame()) {
+    // The next handler address is on top of the frame.  Unlink from
+    // the handler list and drop the rest of this handler from the
+    // frame.
+    ASSERT(StackHandlerConstants::kNextOffset == 0);
+    frame_->EmitPop(Operand::StaticVariable(handler_address));
+    frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
+    if (has_unlinks) {
+      exit.Jump();
+    }
+  }
+
+  // Generate unlink code for the (formerly) shadowing targets that
+  // have been jumped to.  Deallocate each shadow target.
+  Result return_value;
+  for (int i = 0; i < shadows.length(); i++) {
+    if (shadows[i]->is_linked()) {
+      // Unlink from try chain; be careful not to destroy the TOS if
+      // there is one.
+      if (i == kReturnShadowIndex) {
+        shadows[i]->Bind(&return_value);
+        return_value.ToRegister(eax);
+      } else {
+        shadows[i]->Bind();
+      }
+      // Because we can be jumping here (to spilled code) from
+      // unspilled code, we need to reestablish a spilled frame at
+      // this block.
+      frame_->SpillAll();
+
+      // Reload sp from the top handler, because some statements that we
+      // break from (eg, for...in) may have left stuff on the stack.
+      __ mov(esp, Operand::StaticVariable(handler_address));
+      frame_->Forget(frame_->height() - handler_height);
+
+      ASSERT(StackHandlerConstants::kNextOffset == 0);
+      frame_->EmitPop(Operand::StaticVariable(handler_address));
+      frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
+
+      if (i == kReturnShadowIndex) {
+        if (!function_return_is_shadowed_) frame_->PrepareForReturn();
+        shadows[i]->other_target()->Jump(&return_value);
+      } else {
+        shadows[i]->other_target()->Jump();
+      }
+    }
+  }
+
+  exit.Bind();
+}
+
+
+void CodeGenerator::VisitTryFinally(TryFinally* node) {
+  ASSERT(!in_spilled_code());
+  VirtualFrame::SpilledScope spilled_scope;
+  Comment cmnt(masm_, "[ TryFinally");
+  CodeForStatementPosition(node);
+
+  // State: Used to keep track of reason for entering the finally
+  // block. Should probably be extended to hold information for
+  // break/continue from within the try block.
+  enum { FALLING, THROWING, JUMPING };
+
+  JumpTarget try_block;
+  JumpTarget finally_block;
+
+  try_block.Call();
+
+  frame_->EmitPush(eax);
+  // In case of thrown exceptions, this is where we continue.
+  __ Set(ecx, Immediate(Smi::FromInt(THROWING)));
+  finally_block.Jump();
+
+  // --- Try block ---
+  try_block.Bind();
+
+  frame_->PushTryHandler(TRY_FINALLY_HANDLER);
+  int handler_height = frame_->height();
+
+  // Shadow the jump targets for all escapes from the try block, including
+  // returns.  During shadowing, the original target is hidden as the
+  // ShadowTarget and operations on the original actually affect the
+  // shadowing target.
+  //
+  // We should probably try to unify the escaping targets and the return
+  // target.
+  int nof_escapes = node->escaping_targets()->length();
+  List<ShadowTarget*> shadows(1 + nof_escapes);
+
+  // Add the shadow target for the function return.
+  static const int kReturnShadowIndex = 0;
+  shadows.Add(new ShadowTarget(&function_return_));
+  bool function_return_was_shadowed = function_return_is_shadowed_;
+  function_return_is_shadowed_ = true;
+  ASSERT(shadows[kReturnShadowIndex]->other_target() == &function_return_);
+
+  // Add the remaining shadow targets.
+  for (int i = 0; i < nof_escapes; i++) {
+    shadows.Add(new ShadowTarget(node->escaping_targets()->at(i)));
+  }
+
+  // Generate code for the statements in the try block.
+  VisitStatementsAndSpill(node->try_block()->statements());
+
+  // Stop the introduced shadowing and count the number of required unlinks.
+  // After shadowing stops, the original targets are unshadowed and the
+  // ShadowTargets represent the formerly shadowing targets.
+  int nof_unlinks = 0;
+  for (int i = 0; i < shadows.length(); i++) {
+    shadows[i]->StopShadowing();
+    if (shadows[i]->is_linked()) nof_unlinks++;
+  }
+  function_return_is_shadowed_ = function_return_was_shadowed;
+
+  // Get an external reference to the handler address.
+  ExternalReference handler_address(Top::k_handler_address);
+
+  // If we can fall off the end of the try block, unlink from the try
+  // chain and set the state on the frame to FALLING.
+  if (has_valid_frame()) {
+    // The next handler address is on top of the frame.
+    ASSERT(StackHandlerConstants::kNextOffset == 0);
+    frame_->EmitPop(Operand::StaticVariable(handler_address));
+    frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
+
+    // Fake a top of stack value (unneeded when FALLING) and set the
+    // state in ecx, then jump around the unlink blocks if any.
+    frame_->EmitPush(Immediate(Factory::undefined_value()));
+    __ Set(ecx, Immediate(Smi::FromInt(FALLING)));
+    if (nof_unlinks > 0) {
+      finally_block.Jump();
+    }
+  }
+
+  // Generate code to unlink and set the state for the (formerly)
+  // shadowing targets that have been jumped to.
+  for (int i = 0; i < shadows.length(); i++) {
+    if (shadows[i]->is_linked()) {
+      // If we have come from the shadowed return, the return value is
+      // on the virtual frame.  We must preserve it until it is
+      // pushed.
+      if (i == kReturnShadowIndex) {
+        Result return_value;
+        shadows[i]->Bind(&return_value);
+        return_value.ToRegister(eax);
+      } else {
+        shadows[i]->Bind();
+      }
+      // Because we can be jumping here (to spilled code) from
+      // unspilled code, we need to reestablish a spilled frame at
+      // this block.
+      frame_->SpillAll();
+
+      // Reload sp from the top handler, because some statements that
+      // we break from (eg, for...in) may have left stuff on the
+      // stack.
+      __ mov(esp, Operand::StaticVariable(handler_address));
+      frame_->Forget(frame_->height() - handler_height);
+
+      // Unlink this handler and drop it from the frame.
+      ASSERT(StackHandlerConstants::kNextOffset == 0);
+      frame_->EmitPop(Operand::StaticVariable(handler_address));
+      frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
+
+      if (i == kReturnShadowIndex) {
+        // If this target shadowed the function return, materialize
+        // the return value on the stack.
+        frame_->EmitPush(eax);
+      } else {
+        // Fake TOS for targets that shadowed breaks and continues.
+        frame_->EmitPush(Immediate(Factory::undefined_value()));
+      }
+      __ Set(ecx, Immediate(Smi::FromInt(JUMPING + i)));
+      if (--nof_unlinks > 0) {
+        // If this is not the last unlink block, jump around the next.
+        finally_block.Jump();
+      }
+    }
+  }
+
+  // --- Finally block ---
+  finally_block.Bind();
+
+  // Push the state on the stack.
+  frame_->EmitPush(ecx);
+
+  // We keep two elements on the stack - the (possibly faked) result
+  // and the state - while evaluating the finally block.
+  //
+  // Generate code for the statements in the finally block.
+  VisitStatementsAndSpill(node->finally_block()->statements());
+
+  if (has_valid_frame()) {
+    // Restore state and return value or faked TOS.
+    frame_->EmitPop(ecx);
+    frame_->EmitPop(eax);
+  }
+
+  // Generate code to jump to the right destination for all used
+  // formerly shadowing targets.  Deallocate each shadow target.
+  for (int i = 0; i < shadows.length(); i++) {
+    if (has_valid_frame() && shadows[i]->is_bound()) {
+      BreakTarget* original = shadows[i]->other_target();
+      __ cmp(Operand(ecx), Immediate(Smi::FromInt(JUMPING + i)));
+      if (i == kReturnShadowIndex) {
+        // The return value is (already) in eax.
+        Result return_value = allocator_->Allocate(eax);
+        ASSERT(return_value.is_valid());
+        if (function_return_is_shadowed_) {
+          original->Branch(equal, &return_value);
+        } else {
+          // Branch around the preparation for return which may emit
+          // code.
+          JumpTarget skip;
+          skip.Branch(not_equal);
+          frame_->PrepareForReturn();
+          original->Jump(&return_value);
+          skip.Bind();
+        }
+      } else {
+        original->Branch(equal);
+      }
+    }
+  }
+
+  if (has_valid_frame()) {
+    // Check if we need to rethrow the exception.
+    JumpTarget exit;
+    __ cmp(Operand(ecx), Immediate(Smi::FromInt(THROWING)));
+    exit.Branch(not_equal);
+
+    // Rethrow exception.
+    frame_->EmitPush(eax);  // undo pop from above
+    frame_->CallRuntime(Runtime::kReThrow, 1);
+
+    // Done.
+    exit.Bind();
+  }
+}
+
+
+void CodeGenerator::VisitDebuggerStatement(DebuggerStatement* node) {
+  ASSERT(!in_spilled_code());
+  Comment cmnt(masm_, "[ DebuggerStatement");
+  CodeForStatementPosition(node);
+#ifdef ENABLE_DEBUGGER_SUPPORT
+  // Spill everything, even constants, to the frame.
+  frame_->SpillAll();
+  frame_->CallRuntime(Runtime::kDebugBreak, 0);
+  // Ignore the return value.
+#endif
+}
+
+
+void CodeGenerator::InstantiateBoilerplate(Handle<JSFunction> boilerplate) {
+  // Call the runtime to instantiate the function boilerplate object.
+  // The inevitable call will sync frame elements to memory anyway, so
+  // we do it eagerly to allow us to push the arguments directly into
+  // place.
+  ASSERT(boilerplate->IsBoilerplate());
+  frame_->SyncRange(0, frame_->element_count() - 1);
+
+  // Push the boilerplate on the stack.
+  frame_->EmitPush(Immediate(boilerplate));
+
+  // Create a new closure.
+  frame_->EmitPush(esi);
+  Result result = frame_->CallRuntime(Runtime::kNewClosure, 2);
+  frame_->Push(&result);
+}
+
+
+void CodeGenerator::VisitFunctionLiteral(FunctionLiteral* node) {
+  Comment cmnt(masm_, "[ FunctionLiteral");
+
+  // Build the function boilerplate and instantiate it.
+  Handle<JSFunction> boilerplate = BuildBoilerplate(node);
+  // Check for stack-overflow exception.
+  if (HasStackOverflow()) return;
+  InstantiateBoilerplate(boilerplate);
+}
+
+
+void CodeGenerator::VisitFunctionBoilerplateLiteral(
+    FunctionBoilerplateLiteral* node) {
+  Comment cmnt(masm_, "[ FunctionBoilerplateLiteral");
+  InstantiateBoilerplate(node->boilerplate());
+}
+
+
+void CodeGenerator::VisitConditional(Conditional* node) {
+  Comment cmnt(masm_, "[ Conditional");
+  JumpTarget then;
+  JumpTarget else_;
+  JumpTarget exit;
+  ControlDestination dest(&then, &else_, true);
+  LoadCondition(node->condition(), NOT_INSIDE_TYPEOF, &dest, true);
+
+  if (dest.false_was_fall_through()) {
+    // The else target was bound, so we compile the else part first.
+    Load(node->else_expression(), typeof_state());
+
+    if (then.is_linked()) {
+      exit.Jump();
+      then.Bind();
+      Load(node->then_expression(), typeof_state());
+    }
+  } else {
+    // The then target was bound, so we compile the then part first.
+    Load(node->then_expression(), typeof_state());
+
+    if (else_.is_linked()) {
+      exit.Jump();
+      else_.Bind();
+      Load(node->else_expression(), typeof_state());
+    }
+  }
+
+  exit.Bind();
+}
+
+
+void CodeGenerator::LoadFromSlot(Slot* slot, TypeofState typeof_state) {
+  if (slot->type() == Slot::LOOKUP) {
+    ASSERT(slot->var()->is_dynamic());
+
+    JumpTarget slow;
+    JumpTarget done;
+    Result value;
+
+    // Generate fast-case code for variables that might be shadowed by
+    // eval-introduced variables.  Eval is used a lot without
+    // introducing variables.  In those cases, we do not want to
+    // perform a runtime call for all variables in the scope
+    // containing the eval.
+    if (slot->var()->mode() == Variable::DYNAMIC_GLOBAL) {
+      value = LoadFromGlobalSlotCheckExtensions(slot, typeof_state, &slow);
+      // If there was no control flow to slow, we can exit early.
+      if (!slow.is_linked()) {
+        frame_->Push(&value);
+        return;
+      }
+
+      done.Jump(&value);
+
+    } else if (slot->var()->mode() == Variable::DYNAMIC_LOCAL) {
+      Slot* potential_slot = slot->var()->local_if_not_shadowed()->slot();
+      // Only generate the fast case for locals that rewrite to slots.
+      // This rules out argument loads.
+      if (potential_slot != NULL) {
+        // Allocate a fresh register to use as a temp in
+        // ContextSlotOperandCheckExtensions and to hold the result
+        // value.
+        value = allocator_->Allocate();
+        ASSERT(value.is_valid());
+        __ mov(value.reg(),
+               ContextSlotOperandCheckExtensions(potential_slot,
+                                                 value,
+                                                 &slow));
+        if (potential_slot->var()->mode() == Variable::CONST) {
+          __ cmp(value.reg(), Factory::the_hole_value());
+          done.Branch(not_equal, &value);
+          __ mov(value.reg(), Factory::undefined_value());
+        }
+        // There is always control flow to slow from
+        // ContextSlotOperandCheckExtensions so we have to jump around
+        // it.
+        done.Jump(&value);
+      }
+    }
+
+    slow.Bind();
+    // A runtime call is inevitable.  We eagerly sync frame elements
+    // to memory so that we can push the arguments directly into place
+    // on top of the frame.
+    frame_->SyncRange(0, frame_->element_count() - 1);
+    frame_->EmitPush(esi);
+    frame_->EmitPush(Immediate(slot->var()->name()));
+    if (typeof_state == INSIDE_TYPEOF) {
+      value =
+          frame_->CallRuntime(Runtime::kLoadContextSlotNoReferenceError, 2);
+    } else {
+      value = frame_->CallRuntime(Runtime::kLoadContextSlot, 2);
+    }
+
+    done.Bind(&value);
+    frame_->Push(&value);
+
+  } else if (slot->var()->mode() == Variable::CONST) {
+    // Const slots may contain 'the hole' value (the constant hasn't been
+    // initialized yet) which needs to be converted into the 'undefined'
+    // value.
+    //
+    // We currently spill the virtual frame because constants use the
+    // potentially unsafe direct-frame access of SlotOperand.
+    VirtualFrame::SpilledScope spilled_scope;
+    Comment cmnt(masm_, "[ Load const");
+    JumpTarget exit;
+    __ mov(ecx, SlotOperand(slot, ecx));
+    __ cmp(ecx, Factory::the_hole_value());
+    exit.Branch(not_equal);
+    __ mov(ecx, Factory::undefined_value());
+    exit.Bind();
+    frame_->EmitPush(ecx);
+
+  } else if (slot->type() == Slot::PARAMETER) {
+    frame_->PushParameterAt(slot->index());
+
+  } else if (slot->type() == Slot::LOCAL) {
+    frame_->PushLocalAt(slot->index());
+
+  } else {
+    // The other remaining slot types (LOOKUP and GLOBAL) cannot reach
+    // here.
+    //
+    // The use of SlotOperand below is safe for an unspilled frame
+    // because it will always be a context slot.
+    ASSERT(slot->type() == Slot::CONTEXT);
+    Result temp = allocator_->Allocate();
+    ASSERT(temp.is_valid());
+    __ mov(temp.reg(), SlotOperand(slot, temp.reg()));
+    frame_->Push(&temp);
+  }
+}
+
+
+void CodeGenerator::LoadFromSlotCheckForArguments(Slot* slot,
+                                                  TypeofState state) {
+  LoadFromSlot(slot, state);
+
+  // Bail out quickly if we're not using lazy arguments allocation.
+  if (ArgumentsMode() != LAZY_ARGUMENTS_ALLOCATION) return;
+
+  // ... or if the slot isn't a non-parameter arguments slot.
+  if (slot->type() == Slot::PARAMETER || !slot->is_arguments()) return;
+
+  // Pop the loaded value from the stack.
+  Result value = frame_->Pop();
+
+  // If the loaded value is a constant, we know if the arguments
+  // object has been lazily loaded yet.
+  if (value.is_constant()) {
+    if (value.handle()->IsTheHole()) {
+      Result arguments = StoreArgumentsObject(false);
+      frame_->Push(&arguments);
+    } else {
+      frame_->Push(&value);
+    }
+    return;
+  }
+
+  // The loaded value is in a register. If it is the sentinel that
+  // indicates that we haven't loaded the arguments object yet, we
+  // need to do it now.
+  JumpTarget exit;
+  __ cmp(Operand(value.reg()), Immediate(Factory::the_hole_value()));
+  frame_->Push(&value);
+  exit.Branch(not_equal);
+  Result arguments = StoreArgumentsObject(false);
+  frame_->SetElementAt(0, &arguments);
+  exit.Bind();
+}
+
+
+Result CodeGenerator::LoadFromGlobalSlotCheckExtensions(
+    Slot* slot,
+    TypeofState typeof_state,
+    JumpTarget* slow) {
+  // Check that no extension objects have been created by calls to
+  // eval from the current scope to the global scope.
+  Register context = esi;
+  Result tmp = allocator_->Allocate();
+  ASSERT(tmp.is_valid());  // All non-reserved registers were available.
+
+  Scope* s = scope();
+  while (s != NULL) {
+    if (s->num_heap_slots() > 0) {
+      if (s->calls_eval()) {
+        // Check that extension is NULL.
+        __ cmp(ContextOperand(context, Context::EXTENSION_INDEX),
+               Immediate(0));
+        slow->Branch(not_equal, not_taken);
+      }
+      // Load next context in chain.
+      __ mov(tmp.reg(), ContextOperand(context, Context::CLOSURE_INDEX));
+      __ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
+      context = tmp.reg();
+    }
+    // If no outer scope calls eval, we do not need to check more
+    // context extensions.  If we have reached an eval scope, we check
+    // all extensions from this point.
+    if (!s->outer_scope_calls_eval() || s->is_eval_scope()) break;
+    s = s->outer_scope();
+  }
+
+  if (s != NULL && s->is_eval_scope()) {
+    // Loop up the context chain.  There is no frame effect so it is
+    // safe to use raw labels here.
+    Label next, fast;
+    if (!context.is(tmp.reg())) {
+      __ mov(tmp.reg(), context);
+    }
+    __ bind(&next);
+    // Terminate at global context.
+    __ cmp(FieldOperand(tmp.reg(), HeapObject::kMapOffset),
+           Immediate(Factory::global_context_map()));
+    __ j(equal, &fast);
+    // Check that extension is NULL.
+    __ cmp(ContextOperand(tmp.reg(), Context::EXTENSION_INDEX), Immediate(0));
+    slow->Branch(not_equal, not_taken);
+    // Load next context in chain.
+    __ mov(tmp.reg(), ContextOperand(tmp.reg(), Context::CLOSURE_INDEX));
+    __ mov(tmp.reg(), FieldOperand(tmp.reg(), JSFunction::kContextOffset));
+    __ jmp(&next);
+    __ bind(&fast);
+  }
+  tmp.Unuse();
+
+  // All extension objects were empty and it is safe to use a global
+  // load IC call.
+  LoadGlobal();
+  frame_->Push(slot->var()->name());
+  RelocInfo::Mode mode = (typeof_state == INSIDE_TYPEOF)
+                         ? RelocInfo::CODE_TARGET
+                         : RelocInfo::CODE_TARGET_CONTEXT;
+  Result answer = frame_->CallLoadIC(mode);
+  // A test eax instruction following the call signals that the inobject
+  // property case was inlined.  Ensure that there is not a test eax
+  // instruction here.
+  __ nop();
+  // Discard the global object. The result is in answer.
+  frame_->Drop();
+  return answer;
+}
+
+
+void CodeGenerator::StoreToSlot(Slot* slot, InitState init_state) {
+  if (slot->type() == Slot::LOOKUP) {
+    ASSERT(slot->var()->is_dynamic());
+
+    // For now, just do a runtime call.  Since the call is inevitable,
+    // we eagerly sync the virtual frame so we can directly push the
+    // arguments into place.
+    frame_->SyncRange(0, frame_->element_count() - 1);
+
+    frame_->EmitPush(esi);
+    frame_->EmitPush(Immediate(slot->var()->name()));
+
+    Result value;
+    if (init_state == CONST_INIT) {
+      // Same as the case for a normal store, but ignores attribute
+      // (e.g. READ_ONLY) of context slot so that we can initialize const
+      // properties (introduced via eval("const foo = (some expr);")). Also,
+      // uses the current function context instead of the top context.
+      //
+      // Note that we must declare the foo upon entry of eval(), via a
+      // context slot declaration, but we cannot initialize it at the same
+      // time, because the const declaration may be at the end of the eval
+      // code (sigh...) and the const variable may have been used before
+      // (where its value is 'undefined'). Thus, we can only do the
+      // initialization when we actually encounter the expression and when
+      // the expression operands are defined and valid, and thus we need the
+      // split into 2 operations: declaration of the context slot followed
+      // by initialization.
+      value = frame_->CallRuntime(Runtime::kInitializeConstContextSlot, 3);
+    } else {
+      value = frame_->CallRuntime(Runtime::kStoreContextSlot, 3);
+    }
+    // Storing a variable must keep the (new) value on the expression
+    // stack. This is necessary for compiling chained assignment
+    // expressions.
+    frame_->Push(&value);
+
+  } else {
+    ASSERT(!slot->var()->is_dynamic());
+
+    JumpTarget exit;
+    if (init_state == CONST_INIT) {
+      ASSERT(slot->var()->mode() == Variable::CONST);
+      // Only the first const initialization must be executed (the slot
+      // still contains 'the hole' value). When the assignment is executed,
+      // the code is identical to a normal store (see below).
+      //
+      // We spill the frame in the code below because the direct-frame
+      // access of SlotOperand is potentially unsafe with an unspilled
+      // frame.
+      VirtualFrame::SpilledScope spilled_scope;
+      Comment cmnt(masm_, "[ Init const");
+      __ mov(ecx, SlotOperand(slot, ecx));
+      __ cmp(ecx, Factory::the_hole_value());
+      exit.Branch(not_equal);
+    }
+
+    // We must execute the store.  Storing a variable must keep the (new)
+    // value on the stack. This is necessary for compiling assignment
+    // expressions.
+    //
+    // Note: We will reach here even with slot->var()->mode() ==
+    // Variable::CONST because of const declarations which will initialize
+    // consts to 'the hole' value and by doing so, end up calling this code.
+    if (slot->type() == Slot::PARAMETER) {
+      frame_->StoreToParameterAt(slot->index());
+    } else if (slot->type() == Slot::LOCAL) {
+      frame_->StoreToLocalAt(slot->index());
+    } else {
+      // The other slot types (LOOKUP and GLOBAL) cannot reach here.
+      //
+      // The use of SlotOperand below is safe for an unspilled frame
+      // because the slot is a context slot.
+      ASSERT(slot->type() == Slot::CONTEXT);
+      frame_->Dup();
+      Result value = frame_->Pop();
+      value.ToRegister();
+      Result start = allocator_->Allocate();
+      ASSERT(start.is_valid());
+      __ mov(SlotOperand(slot, start.reg()), value.reg());
+      // RecordWrite may destroy the value registers.
+      //
+      // TODO(204): Avoid actually spilling when the value is not
+      // needed (probably the common case).
+      frame_->Spill(value.reg());
+      int offset = FixedArray::kHeaderSize + slot->index() * kPointerSize;
+      Result temp = allocator_->Allocate();
+      ASSERT(temp.is_valid());
+      __ RecordWrite(start.reg(), offset, value.reg(), temp.reg());
+      // The results start, value, and temp are unused by going out of
+      // scope.
+    }
+
+    exit.Bind();
+  }
+}
+
+
+void CodeGenerator::VisitSlot(Slot* node) {
+  Comment cmnt(masm_, "[ Slot");
+  LoadFromSlotCheckForArguments(node, typeof_state());
+}
+
+
+void CodeGenerator::VisitVariableProxy(VariableProxy* node) {
+  Comment cmnt(masm_, "[ VariableProxy");
+  Variable* var = node->var();
+  Expression* expr = var->rewrite();
+  if (expr != NULL) {
+    Visit(expr);
+  } else {
+    ASSERT(var->is_global());
+    Reference ref(this, node);
+    ref.GetValue(typeof_state());
+  }
+}
+
+
+void CodeGenerator::VisitLiteral(Literal* node) {
+  Comment cmnt(masm_, "[ Literal");
+  frame_->Push(node->handle());
+}
+
+
+void CodeGenerator::LoadUnsafeSmi(Register target, Handle<Object> value) {
+  ASSERT(target.is_valid());
+  ASSERT(value->IsSmi());
+  int bits = reinterpret_cast<int>(*value);
+  __ Set(target, Immediate(bits & 0x0000FFFF));
+  __ xor_(target, bits & 0xFFFF0000);
+}
+
+
+bool CodeGenerator::IsUnsafeSmi(Handle<Object> value) {
+  if (!value->IsSmi()) return false;
+  int int_value = Smi::cast(*value)->value();
+  return !is_intn(int_value, kMaxSmiInlinedBits);
+}
+
+
+// Materialize the regexp literal 'node' in the literals array
+// 'literals' of the function.  Leave the regexp boilerplate in
+// 'boilerplate'.
+class DeferredRegExpLiteral: public DeferredCode {
+ public:
+  DeferredRegExpLiteral(Register boilerplate,
+                        Register literals,
+                        RegExpLiteral* node)
+      : boilerplate_(boilerplate), literals_(literals), node_(node) {
+    set_comment("[ DeferredRegExpLiteral");
+  }
+
+  void Generate();
+
+ private:
+  Register boilerplate_;
+  Register literals_;
+  RegExpLiteral* node_;
+};
+
+
+void DeferredRegExpLiteral::Generate() {
+  // Since the entry is undefined we call the runtime system to
+  // compute the literal.
+  // Literal array (0).
+  __ push(literals_);
+  // Literal index (1).
+  __ push(Immediate(Smi::FromInt(node_->literal_index())));
+  // RegExp pattern (2).
+  __ push(Immediate(node_->pattern()));
+  // RegExp flags (3).
+  __ push(Immediate(node_->flags()));
+  __ CallRuntime(Runtime::kMaterializeRegExpLiteral, 4);
+  if (!boilerplate_.is(eax)) __ mov(boilerplate_, eax);
+}
+
+
+void CodeGenerator::VisitRegExpLiteral(RegExpLiteral* node) {
+  Comment cmnt(masm_, "[ RegExp Literal");
+
+  // Retrieve the literals array and check the allocated entry.  Begin
+  // with a writable copy of the function of this activation in a
+  // register.
+  frame_->PushFunction();
+  Result literals = frame_->Pop();
+  literals.ToRegister();
+  frame_->Spill(literals.reg());
+
+  // Load the literals array of the function.
+  __ mov(literals.reg(),
+         FieldOperand(literals.reg(), JSFunction::kLiteralsOffset));
+
+  // Load the literal at the ast saved index.
+  Result boilerplate = allocator_->Allocate();
+  ASSERT(boilerplate.is_valid());
+  int literal_offset =
+      FixedArray::kHeaderSize + node->literal_index() * kPointerSize;
+  __ mov(boilerplate.reg(), FieldOperand(literals.reg(), literal_offset));
+
+  // Check whether we need to materialize the RegExp object.  If so,
+  // jump to the deferred code passing the literals array.
+  DeferredRegExpLiteral* deferred =
+      new DeferredRegExpLiteral(boilerplate.reg(), literals.reg(), node);
+  __ cmp(boilerplate.reg(), Factory::undefined_value());
+  deferred->Branch(equal);
+  deferred->BindExit();
+  literals.Unuse();
+
+  // Push the boilerplate object.
+  frame_->Push(&boilerplate);
+}
+
+
+// Materialize the object literal 'node' in the literals array
+// 'literals' of the function.  Leave the object boilerplate in
+// 'boilerplate'.
+class DeferredObjectLiteral: public DeferredCode {
+ public:
+  DeferredObjectLiteral(Register boilerplate,
+                        Register literals,
+                        ObjectLiteral* node)
+      : boilerplate_(boilerplate), literals_(literals), node_(node) {
+    set_comment("[ DeferredObjectLiteral");
+  }
+
+  void Generate();
+
+ private:
+  Register boilerplate_;
+  Register literals_;
+  ObjectLiteral* node_;
+};
+
+
+void DeferredObjectLiteral::Generate() {
+  // Since the entry is undefined we call the runtime system to
+  // compute the literal.
+  // Literal array (0).
+  __ push(literals_);
+  // Literal index (1).
+  __ push(Immediate(Smi::FromInt(node_->literal_index())));
+  // Constant properties (2).
+  __ push(Immediate(node_->constant_properties()));
+  __ CallRuntime(Runtime::kCreateObjectLiteralBoilerplate, 3);
+  if (!boilerplate_.is(eax)) __ mov(boilerplate_, eax);
+}
+
+
+void CodeGenerator::VisitObjectLiteral(ObjectLiteral* node) {
+  Comment cmnt(masm_, "[ ObjectLiteral");
+
+  // Retrieve the literals array and check the allocated entry.  Begin
+  // with a writable copy of the function of this activation in a
+  // register.
+  frame_->PushFunction();
+  Result literals = frame_->Pop();
+  literals.ToRegister();
+  frame_->Spill(literals.reg());
+
+  // Load the literals array of the function.
+  __ mov(literals.reg(),
+         FieldOperand(literals.reg(), JSFunction::kLiteralsOffset));
+
+  // Load the literal at the ast saved index.
+  Result boilerplate = allocator_->Allocate();
+  ASSERT(boilerplate.is_valid());
+  int literal_offset =
+      FixedArray::kHeaderSize + node->literal_index() * kPointerSize;
+  __ mov(boilerplate.reg(), FieldOperand(literals.reg(), literal_offset));
+
+  // Check whether we need to materialize the object literal boilerplate.
+  // If so, jump to the deferred code passing the literals array.
+  DeferredObjectLiteral* deferred =
+      new DeferredObjectLiteral(boilerplate.reg(), literals.reg(), node);
+  __ cmp(boilerplate.reg(), Factory::undefined_value());
+  deferred->Branch(equal);
+  deferred->BindExit();
+  literals.Unuse();
+
+  // Push the boilerplate object.
+  frame_->Push(&boilerplate);
+  // Clone the boilerplate object.
+  Runtime::FunctionId clone_function_id = Runtime::kCloneLiteralBoilerplate;
+  if (node->depth() == 1) {
+    clone_function_id = Runtime::kCloneShallowLiteralBoilerplate;
+  }
+  Result clone = frame_->CallRuntime(clone_function_id, 1);
+  // Push the newly cloned literal object as the result.
+  frame_->Push(&clone);
+
+  for (int i = 0; i < node->properties()->length(); i++) {
+    ObjectLiteral::Property* property = node->properties()->at(i);
+    switch (property->kind()) {
+      case ObjectLiteral::Property::CONSTANT:
+        break;
+      case ObjectLiteral::Property::MATERIALIZED_LITERAL:
+        if (CompileTimeValue::IsCompileTimeValue(property->value())) break;
+        // else fall through.
+      case ObjectLiteral::Property::COMPUTED: {
+        Handle<Object> key(property->key()->handle());
+        if (key->IsSymbol()) {
+          // Duplicate the object as the IC receiver.
+          frame_->Dup();
+          Load(property->value());
+          frame_->Push(key);
+          Result ignored = frame_->CallStoreIC();
+          // Drop the duplicated receiver and ignore the result.
+          frame_->Drop();
+          break;
+        }
+        // Fall through
+      }
+      case ObjectLiteral::Property::PROTOTYPE: {
+        // Duplicate the object as an argument to the runtime call.
+        frame_->Dup();
+        Load(property->key());
+        Load(property->value());
+        Result ignored = frame_->CallRuntime(Runtime::kSetProperty, 3);
+        // Ignore the result.
+        break;
+      }
+      case ObjectLiteral::Property::SETTER: {
+        // Duplicate the object as an argument to the runtime call.
+        frame_->Dup();
+        Load(property->key());
+        frame_->Push(Smi::FromInt(1));
+        Load(property->value());
+        Result ignored = frame_->CallRuntime(Runtime::kDefineAccessor, 4);
+        // Ignore the result.
+        break;
+      }
+      case ObjectLiteral::Property::GETTER: {
+        // Duplicate the object as an argument to the runtime call.
+        frame_->Dup();
+        Load(property->key());
+        frame_->Push(Smi::FromInt(0));
+        Load(property->value());
+        Result ignored = frame_->CallRuntime(Runtime::kDefineAccessor, 4);
+        // Ignore the result.
+        break;
+      }
+      default: UNREACHABLE();
+    }
+  }
+}
+
+
+// Materialize the array literal 'node' in the literals array 'literals'
+// of the function.  Leave the array boilerplate in 'boilerplate'.
+class DeferredArrayLiteral: public DeferredCode {
+ public:
+  DeferredArrayLiteral(Register boilerplate,
+                       Register literals,
+                       ArrayLiteral* node)
+      : boilerplate_(boilerplate), literals_(literals), node_(node) {
+    set_comment("[ DeferredArrayLiteral");
+  }
+
+  void Generate();
+
+ private:
+  Register boilerplate_;
+  Register literals_;
+  ArrayLiteral* node_;
+};
+
+
+void DeferredArrayLiteral::Generate() {
+  // Since the entry is undefined we call the runtime system to
+  // compute the literal.
+  // Literal array (0).
+  __ push(literals_);
+  // Literal index (1).
+  __ push(Immediate(Smi::FromInt(node_->literal_index())));
+  // Constant properties (2).
+  __ push(Immediate(node_->literals()));
+  __ CallRuntime(Runtime::kCreateArrayLiteralBoilerplate, 3);
+  if (!boilerplate_.is(eax)) __ mov(boilerplate_, eax);
+}
+
+
+void CodeGenerator::VisitArrayLiteral(ArrayLiteral* node) {
+  Comment cmnt(masm_, "[ ArrayLiteral");
+
+  // Retrieve the literals array and check the allocated entry.  Begin
+  // with a writable copy of the function of this activation in a
+  // register.
+  frame_->PushFunction();
+  Result literals = frame_->Pop();
+  literals.ToRegister();
+  frame_->Spill(literals.reg());
+
+  // Load the literals array of the function.
+  __ mov(literals.reg(),
+         FieldOperand(literals.reg(), JSFunction::kLiteralsOffset));
+
+  // Load the literal at the ast saved index.
+  Result boilerplate = allocator_->Allocate();
+  ASSERT(boilerplate.is_valid());
+  int literal_offset =
+      FixedArray::kHeaderSize + node->literal_index() * kPointerSize;
+  __ mov(boilerplate.reg(), FieldOperand(literals.reg(), literal_offset));
+
+  // Check whether we need to materialize the object literal boilerplate.
+  // If so, jump to the deferred code passing the literals array.
+  DeferredArrayLiteral* deferred =
+      new DeferredArrayLiteral(boilerplate.reg(), literals.reg(), node);
+  __ cmp(boilerplate.reg(), Factory::undefined_value());
+  deferred->Branch(equal);
+  deferred->BindExit();
+  literals.Unuse();
+
+  // Push the resulting array literal boilerplate on the stack.
+  frame_->Push(&boilerplate);
+  // Clone the boilerplate object.
+  Runtime::FunctionId clone_function_id = Runtime::kCloneLiteralBoilerplate;
+  if (node->depth() == 1) {
+    clone_function_id = Runtime::kCloneShallowLiteralBoilerplate;
+  }
+  Result clone = frame_->CallRuntime(clone_function_id, 1);
+  // Push the newly cloned literal object as the result.
+  frame_->Push(&clone);
+
+  // Generate code to set the elements in the array that are not
+  // literals.
+  for (int i = 0; i < node->values()->length(); i++) {
+    Expression* value = node->values()->at(i);
+
+    // If value is a literal the property value is already set in the
+    // boilerplate object.
+    if (value->AsLiteral() != NULL) continue;
+    // If value is a materialized literal the property value is already set
+    // in the boilerplate object if it is simple.
+    if (CompileTimeValue::IsCompileTimeValue(value)) continue;
+
+    // The property must be set by generated code.
+    Load(value);
+
+    // Get the property value off the stack.
+    Result prop_value = frame_->Pop();
+    prop_value.ToRegister();
+
+    // Fetch the array literal while leaving a copy on the stack and
+    // use it to get the elements array.
+    frame_->Dup();
+    Result elements = frame_->Pop();
+    elements.ToRegister();
+    frame_->Spill(elements.reg());
+    // Get the elements array.
+    __ mov(elements.reg(),
+           FieldOperand(elements.reg(), JSObject::kElementsOffset));
+
+    // Write to the indexed properties array.
+    int offset = i * kPointerSize + FixedArray::kHeaderSize;
+    __ mov(FieldOperand(elements.reg(), offset), prop_value.reg());
+
+    // Update the write barrier for the array address.
+    frame_->Spill(prop_value.reg());  // Overwritten by the write barrier.
+    Result scratch = allocator_->Allocate();
+    ASSERT(scratch.is_valid());
+    __ RecordWrite(elements.reg(), offset, prop_value.reg(), scratch.reg());
+  }
+}
+
+
+void CodeGenerator::VisitCatchExtensionObject(CatchExtensionObject* node) {
+  ASSERT(!in_spilled_code());
+  // Call runtime routine to allocate the catch extension object and
+  // assign the exception value to the catch variable.
+  Comment cmnt(masm_, "[ CatchExtensionObject");
+  Load(node->key());
+  Load(node->value());
+  Result result =
+      frame_->CallRuntime(Runtime::kCreateCatchExtensionObject, 2);
+  frame_->Push(&result);
+}
+
+
+void CodeGenerator::VisitAssignment(Assignment* node) {
+  Comment cmnt(masm_, "[ Assignment");
+
+  { Reference target(this, node->target());
+    if (target.is_illegal()) {
+      // Fool the virtual frame into thinking that we left the assignment's
+      // value on the frame.
+      frame_->Push(Smi::FromInt(0));
+      return;
+    }
+    Variable* var = node->target()->AsVariableProxy()->AsVariable();
+
+    if (node->starts_initialization_block()) {
+      ASSERT(target.type() == Reference::NAMED ||
+             target.type() == Reference::KEYED);
+      // Change to slow case in the beginning of an initialization
+      // block to avoid the quadratic behavior of repeatedly adding
+      // fast properties.
+
+      // The receiver is the argument to the runtime call.  It is the
+      // first value pushed when the reference was loaded to the
+      // frame.
+      frame_->PushElementAt(target.size() - 1);
+      Result ignored = frame_->CallRuntime(Runtime::kToSlowProperties, 1);
+    }
+    if (node->op() == Token::ASSIGN ||
+        node->op() == Token::INIT_VAR ||
+        node->op() == Token::INIT_CONST) {
+      Load(node->value());
+
+    } else {
+      Literal* literal = node->value()->AsLiteral();
+      bool overwrite_value =
+          (node->value()->AsBinaryOperation() != NULL &&
+           node->value()->AsBinaryOperation()->ResultOverwriteAllowed());
+      Variable* right_var = node->value()->AsVariableProxy()->AsVariable();
+      // There are two cases where the target is not read in the right hand
+      // side, that are easy to test for: the right hand side is a literal,
+      // or the right hand side is a different variable.  TakeValue invalidates
+      // the target, with an implicit promise that it will be written to again
+      // before it is read.
+      if (literal != NULL || (right_var != NULL && right_var != var)) {
+        target.TakeValue(NOT_INSIDE_TYPEOF);
+      } else {
+        target.GetValue(NOT_INSIDE_TYPEOF);
+      }
+      Load(node->value());
+      GenericBinaryOperation(node->binary_op(),
+                             node->type(),
+                             overwrite_value ? OVERWRITE_RIGHT : NO_OVERWRITE);
+    }
+
+    if (var != NULL &&
+        var->mode() == Variable::CONST &&
+        node->op() != Token::INIT_VAR && node->op() != Token::INIT_CONST) {
+      // Assignment ignored - leave the value on the stack.
+    } else {
+      CodeForSourcePosition(node->position());
+      if (node->op() == Token::INIT_CONST) {
+        // Dynamic constant initializations must use the function context
+        // and initialize the actual constant declared. Dynamic variable
+        // initializations are simply assignments and use SetValue.
+        target.SetValue(CONST_INIT);
+      } else {
+        target.SetValue(NOT_CONST_INIT);
+      }
+      if (node->ends_initialization_block()) {
+        ASSERT(target.type() == Reference::NAMED ||
+               target.type() == Reference::KEYED);
+        // End of initialization block. Revert to fast case.  The
+        // argument to the runtime call is the receiver, which is the
+        // first value pushed as part of the reference, which is below
+        // the lhs value.
+        frame_->PushElementAt(target.size());
+        Result ignored = frame_->CallRuntime(Runtime::kToFastProperties, 1);
+      }
+    }
+  }
+}
+
+
+void CodeGenerator::VisitThrow(Throw* node) {
+  Comment cmnt(masm_, "[ Throw");
+  Load(node->exception());
+  Result result = frame_->CallRuntime(Runtime::kThrow, 1);
+  frame_->Push(&result);
+}
+
+
+void CodeGenerator::VisitProperty(Property* node) {
+  Comment cmnt(masm_, "[ Property");
+  Reference property(this, node);
+  property.GetValue(typeof_state());
+}
+
+
+void CodeGenerator::VisitCall(Call* node) {
+  Comment cmnt(masm_, "[ Call");
+
+  Expression* function = node->expression();
+  ZoneList<Expression*>* args = node->arguments();
+
+  // Check if the function is a variable or a property.
+  Variable* var = function->AsVariableProxy()->AsVariable();
+  Property* property = function->AsProperty();
+
+  // ------------------------------------------------------------------------
+  // Fast-case: Use inline caching.
+  // ---
+  // According to ECMA-262, section 11.2.3, page 44, the function to call
+  // must be resolved after the arguments have been evaluated. The IC code
+  // automatically handles this by loading the arguments before the function
+  // is resolved in cache misses (this also holds for megamorphic calls).
+  // ------------------------------------------------------------------------
+
+  if (var != NULL && var->is_possibly_eval()) {
+    // ----------------------------------
+    // JavaScript example: 'eval(arg)'  // eval is not known to be shadowed
+    // ----------------------------------
+
+    // In a call to eval, we first call %ResolvePossiblyDirectEval to
+    // resolve the function we need to call and the receiver of the
+    // call.  Then we call the resolved function using the given
+    // arguments.
+
+    // Prepare the stack for the call to the resolved function.
+    Load(function);
+
+    // Allocate a frame slot for the receiver.
+    frame_->Push(Factory::undefined_value());
+    int arg_count = args->length();
+    for (int i = 0; i < arg_count; i++) {
+      Load(args->at(i));
+    }
+
+    // Prepare the stack for the call to ResolvePossiblyDirectEval.
+    frame_->PushElementAt(arg_count + 1);
+    if (arg_count > 0) {
+      frame_->PushElementAt(arg_count);
+    } else {
+      frame_->Push(Factory::undefined_value());
+    }
+
+    // Resolve the call.
+    Result result =
+        frame_->CallRuntime(Runtime::kResolvePossiblyDirectEval, 2);
+
+    // Touch up the stack with the right values for the function and the
+    // receiver.  Use a scratch register to avoid destroying the result.
+    Result scratch = allocator_->Allocate();
+    ASSERT(scratch.is_valid());
+    __ mov(scratch.reg(), FieldOperand(result.reg(), FixedArray::kHeaderSize));
+    frame_->SetElementAt(arg_count + 1, &scratch);
+
+    // We can reuse the result register now.
+    frame_->Spill(result.reg());
+    __ mov(result.reg(),
+           FieldOperand(result.reg(), FixedArray::kHeaderSize + kPointerSize));
+    frame_->SetElementAt(arg_count, &result);
+
+    // Call the function.
+    CodeForSourcePosition(node->position());
+    InLoopFlag in_loop = loop_nesting() > 0 ? IN_LOOP : NOT_IN_LOOP;
+    CallFunctionStub call_function(arg_count, in_loop);
+    result = frame_->CallStub(&call_function, arg_count + 1);
+
+    // Restore the context and overwrite the function on the stack with
+    // the result.
+    frame_->RestoreContextRegister();
+    frame_->SetElementAt(0, &result);
+
+  } else if (var != NULL && !var->is_this() && var->is_global()) {
+    // ----------------------------------
+    // JavaScript example: 'foo(1, 2, 3)'  // foo is global
+    // ----------------------------------
+
+    // Push the name of the function and the receiver onto the stack.
+    frame_->Push(var->name());
+
+    // Pass the global object as the receiver and let the IC stub
+    // patch the stack to use the global proxy as 'this' in the
+    // invoked function.
+    LoadGlobal();
+
+    // Load the arguments.
+    int arg_count = args->length();
+    for (int i = 0; i < arg_count; i++) {
+      Load(args->at(i));
+    }
+
+    // Call the IC initialization code.
+    CodeForSourcePosition(node->position());
+    Result result = frame_->CallCallIC(RelocInfo::CODE_TARGET_CONTEXT,
+                                       arg_count,
+                                       loop_nesting());
+    frame_->RestoreContextRegister();
+    // Replace the function on the stack with the result.
+    frame_->SetElementAt(0, &result);
+
+  } else if (var != NULL && var->slot() != NULL &&
+             var->slot()->type() == Slot::LOOKUP) {
+    // ----------------------------------
+    // JavaScript example: 'with (obj) foo(1, 2, 3)'  // foo is in obj
+    // ----------------------------------
+
+    // Load the function from the context.  Sync the frame so we can
+    // push the arguments directly into place.
+    frame_->SyncRange(0, frame_->element_count() - 1);
+    frame_->EmitPush(esi);
+    frame_->EmitPush(Immediate(var->name()));
+    frame_->CallRuntime(Runtime::kLoadContextSlot, 2);
+    // The runtime call returns a pair of values in eax and edx.  The
+    // looked-up function is in eax and the receiver is in edx.  These
+    // register references are not ref counted here.  We spill them
+    // eagerly since they are arguments to an inevitable call (and are
+    // not sharable by the arguments).
+    ASSERT(!allocator()->is_used(eax));
+    frame_->EmitPush(eax);
+
+    // Load the receiver.
+    ASSERT(!allocator()->is_used(edx));
+    frame_->EmitPush(edx);
+
+    // Call the function.
+    CallWithArguments(args, node->position());
+
+  } else if (property != NULL) {
+    // Check if the key is a literal string.
+    Literal* literal = property->key()->AsLiteral();
+
+    if (literal != NULL && literal->handle()->IsSymbol()) {
+      // ------------------------------------------------------------------
+      // JavaScript example: 'object.foo(1, 2, 3)' or 'map["key"](1, 2, 3)'
+      // ------------------------------------------------------------------
+
+      Handle<String> name = Handle<String>::cast(literal->handle());
+
+      if (ArgumentsMode() == LAZY_ARGUMENTS_ALLOCATION &&
+          name->IsEqualTo(CStrVector("apply")) &&
+          args->length() == 2 &&
+          args->at(1)->AsVariableProxy() != NULL &&
+          args->at(1)->AsVariableProxy()->IsArguments()) {
+        // Use the optimized Function.prototype.apply that avoids
+        // allocating lazily allocated arguments objects.
+        CallApplyLazy(property,
+                      args->at(0),
+                      args->at(1)->AsVariableProxy(),
+                      node->position());
+
+      } else {
+        // Push the name of the function and the receiver onto the stack.
+        frame_->Push(name);
+        Load(property->obj());
+
+        // Load the arguments.
+        int arg_count = args->length();
+        for (int i = 0; i < arg_count; i++) {
+          Load(args->at(i));
+        }
+
+        // Call the IC initialization code.
+        CodeForSourcePosition(node->position());
+        Result result =
+            frame_->CallCallIC(RelocInfo::CODE_TARGET, arg_count,
+                               loop_nesting());
+        frame_->RestoreContextRegister();
+        // Replace the function on the stack with the result.
+        frame_->SetElementAt(0, &result);
+      }
+
+    } else {
+      // -------------------------------------------
+      // JavaScript example: 'array[index](1, 2, 3)'
+      // -------------------------------------------
+
+      // Load the function to call from the property through a reference.
+      Reference ref(this, property);
+      ref.GetValue(NOT_INSIDE_TYPEOF);
+
+      // Pass receiver to called function.
+      if (property->is_synthetic()) {
+        // Use global object as receiver.
+        LoadGlobalReceiver();
+      } else {
+        // The reference's size is non-negative.
+        frame_->PushElementAt(ref.size());
+      }
+
+      // Call the function.
+      CallWithArguments(args, node->position());
+    }
+
+  } else {
+    // ----------------------------------
+    // JavaScript example: 'foo(1, 2, 3)'  // foo is not global
+    // ----------------------------------
+
+    // Load the function.
+    Load(function);
+
+    // Pass the global proxy as the receiver.
+    LoadGlobalReceiver();
+
+    // Call the function.
+    CallWithArguments(args, node->position());
+  }
+}
+
+
+void CodeGenerator::VisitCallNew(CallNew* node) {
+  Comment cmnt(masm_, "[ CallNew");
+
+  // According to ECMA-262, section 11.2.2, page 44, the function
+  // expression in new calls must be evaluated before the
+  // arguments. This is different from ordinary calls, where the
+  // actual function to call is resolved after the arguments have been
+  // evaluated.
+
+  // Compute function to call and use the global object as the
+  // receiver. There is no need to use the global proxy here because
+  // it will always be replaced with a newly allocated object.
+  Load(node->expression());
+  LoadGlobal();
+
+  // Push the arguments ("left-to-right") on the stack.
+  ZoneList<Expression*>* args = node->arguments();
+  int arg_count = args->length();
+  for (int i = 0; i < arg_count; i++) {
+    Load(args->at(i));
+  }
+
+  // Call the construct call builtin that handles allocation and
+  // constructor invocation.
+  CodeForSourcePosition(node->position());
+  Result result = frame_->CallConstructor(arg_count);
+  // Replace the function on the stack with the result.
+  frame_->SetElementAt(0, &result);
+}
+
+
+void CodeGenerator::GenerateIsSmi(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+  Load(args->at(0));
+  Result value = frame_->Pop();
+  value.ToRegister();
+  ASSERT(value.is_valid());
+  __ test(value.reg(), Immediate(kSmiTagMask));
+  value.Unuse();
+  destination()->Split(zero);
+}
+
+
+void CodeGenerator::GenerateLog(ZoneList<Expression*>* args) {
+  // Conditionally generate a log call.
+  // Args:
+  //   0 (literal string): The type of logging (corresponds to the flags).
+  //     This is used to determine whether or not to generate the log call.
+  //   1 (string): Format string.  Access the string at argument index 2
+  //     with '%2s' (see Logger::LogRuntime for all the formats).
+  //   2 (array): Arguments to the format string.
+  ASSERT_EQ(args->length(), 3);
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  if (ShouldGenerateLog(args->at(0))) {
+    Load(args->at(1));
+    Load(args->at(2));
+    frame_->CallRuntime(Runtime::kLog, 2);
+  }
+#endif
+  // Finally, we're expected to leave a value on the top of the stack.
+  frame_->Push(Factory::undefined_value());
+}
+
+
+void CodeGenerator::GenerateIsNonNegativeSmi(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+  Load(args->at(0));
+  Result value = frame_->Pop();
+  value.ToRegister();
+  ASSERT(value.is_valid());
+  __ test(value.reg(), Immediate(kSmiTagMask | 0x80000000));
+  value.Unuse();
+  destination()->Split(zero);
+}
+
+
+// This generates code that performs a charCodeAt() call or returns
+// undefined in order to trigger the slow case, Runtime_StringCharCodeAt.
+// It can handle flat and sliced strings, 8 and 16 bit characters and
+// cons strings where the answer is found in the left hand branch of the
+// cons.  The slow case will flatten the string, which will ensure that
+// the answer is in the left hand side the next time around.
+void CodeGenerator::GenerateFastCharCodeAt(ZoneList<Expression*>* args) {
+  Comment(masm_, "[ GenerateFastCharCodeAt");
+  ASSERT(args->length() == 2);
+
+  Label slow_case;
+  Label end;
+  Label not_a_flat_string;
+  Label a_cons_string;
+  Label try_again_with_new_string;
+  Label ascii_string;
+  Label got_char_code;
+
+  Load(args->at(0));
+  Load(args->at(1));
+  Result index = frame_->Pop();
+  Result object = frame_->Pop();
+
+  // Get register ecx to use as shift amount later.
+  Result shift_amount;
+  if (object.is_register() && object.reg().is(ecx)) {
+    Result fresh = allocator_->Allocate();
+    shift_amount = object;
+    object = fresh;
+    __ mov(object.reg(), ecx);
+  }
+  if (index.is_register() && index.reg().is(ecx)) {
+    Result fresh = allocator_->Allocate();
+    shift_amount = index;
+    index = fresh;
+    __ mov(index.reg(), ecx);
+  }
+  // There could be references to ecx in the frame. Allocating will
+  // spill them, otherwise spill explicitly.
+  if (shift_amount.is_valid()) {
+    frame_->Spill(ecx);
+  } else {
+    shift_amount = allocator()->Allocate(ecx);
+  }
+  ASSERT(shift_amount.is_register());
+  ASSERT(shift_amount.reg().is(ecx));
+  ASSERT(allocator_->count(ecx) == 1);
+
+  // We will mutate the index register and possibly the object register.
+  // The case where they are somehow the same register is handled
+  // because we only mutate them in the case where the receiver is a
+  // heap object and the index is not.
+  object.ToRegister();
+  index.ToRegister();
+  frame_->Spill(object.reg());
+  frame_->Spill(index.reg());
+
+  // We need a single extra temporary register.
+  Result temp = allocator()->Allocate();
+  ASSERT(temp.is_valid());
+
+  // There is no virtual frame effect from here up to the final result
+  // push.
+
+  // If the receiver is a smi trigger the slow case.
+  ASSERT(kSmiTag == 0);
+  __ test(object.reg(), Immediate(kSmiTagMask));
+  __ j(zero, &slow_case);
+
+  // If the index is negative or non-smi trigger the slow case.
+  ASSERT(kSmiTag == 0);
+  __ test(index.reg(), Immediate(kSmiTagMask | 0x80000000));
+  __ j(not_zero, &slow_case);
+  // Untag the index.
+  __ sar(index.reg(), kSmiTagSize);
+
+  __ bind(&try_again_with_new_string);
+  // Fetch the instance type of the receiver into ecx.
+  __ mov(ecx, FieldOperand(object.reg(), HeapObject::kMapOffset));
+  __ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
+  // If the receiver is not a string trigger the slow case.
+  __ test(ecx, Immediate(kIsNotStringMask));
+  __ j(not_zero, &slow_case);
+
+  // Here we make assumptions about the tag values and the shifts needed.
+  // See the comment in objects.h.
+  ASSERT(kLongStringTag == 0);
+  ASSERT(kMediumStringTag + String::kLongLengthShift ==
+         String::kMediumLengthShift);
+  ASSERT(kShortStringTag + String::kLongLengthShift ==
+         String::kShortLengthShift);
+  __ and_(ecx, kStringSizeMask);
+  __ add(Operand(ecx), Immediate(String::kLongLengthShift));
+  // Fetch the length field into the temporary register.
+  __ mov(temp.reg(), FieldOperand(object.reg(), String::kLengthOffset));
+  __ shr(temp.reg());  // The shift amount in ecx is implicit operand.
+  // Check for index out of range.
+  __ cmp(index.reg(), Operand(temp.reg()));
+  __ j(greater_equal, &slow_case);
+  // Reload the instance type (into the temp register this time)..
+  __ mov(temp.reg(), FieldOperand(object.reg(), HeapObject::kMapOffset));
+  __ movzx_b(temp.reg(), FieldOperand(temp.reg(), Map::kInstanceTypeOffset));
+
+  // We need special handling for non-flat strings.
+  ASSERT(kSeqStringTag == 0);
+  __ test(temp.reg(), Immediate(kStringRepresentationMask));
+  __ j(not_zero, &not_a_flat_string);
+  // Check for 1-byte or 2-byte string.
+  __ test(temp.reg(), Immediate(kStringEncodingMask));
+  __ j(not_zero, &ascii_string);
+
+  // 2-byte string.
+  // Load the 2-byte character code into the temp register.
+  __ movzx_w(temp.reg(), FieldOperand(object.reg(),
+                                      index.reg(),
+                                      times_2,
+                                      SeqTwoByteString::kHeaderSize));
+  __ jmp(&got_char_code);
+
+  // ASCII string.
+  __ bind(&ascii_string);
+  // Load the byte into the temp register.
+  __ movzx_b(temp.reg(), FieldOperand(object.reg(),
+                                      index.reg(),
+                                      times_1,
+                                      SeqAsciiString::kHeaderSize));
+  __ bind(&got_char_code);
+  ASSERT(kSmiTag == 0);
+  __ shl(temp.reg(), kSmiTagSize);
+  __ jmp(&end);
+
+  // Handle non-flat strings.
+  __ bind(&not_a_flat_string);
+  __ and_(temp.reg(), kStringRepresentationMask);
+  __ cmp(temp.reg(), kConsStringTag);
+  __ j(equal, &a_cons_string);
+  __ cmp(temp.reg(), kSlicedStringTag);
+  __ j(not_equal, &slow_case);
+
+  // SlicedString.
+  // Add the offset to the index and trigger the slow case on overflow.
+  __ add(index.reg(), FieldOperand(object.reg(), SlicedString::kStartOffset));
+  __ j(overflow, &slow_case);
+  // Getting the underlying string is done by running the cons string code.
+
+  // ConsString.
+  __ bind(&a_cons_string);
+  // Get the first of the two strings.  Both sliced and cons strings
+  // store their source string at the same offset.
+  ASSERT(SlicedString::kBufferOffset == ConsString::kFirstOffset);
+  __ mov(object.reg(), FieldOperand(object.reg(), ConsString::kFirstOffset));
+  __ jmp(&try_again_with_new_string);
+
+  __ bind(&slow_case);
+  // Move the undefined value into the result register, which will
+  // trigger the slow case.
+  __ Set(temp.reg(), Immediate(Factory::undefined_value()));
+
+  __ bind(&end);
+  frame_->Push(&temp);
+}
+
+
+void CodeGenerator::GenerateIsArray(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+  Load(args->at(0));
+  Result value = frame_->Pop();
+  value.ToRegister();
+  ASSERT(value.is_valid());
+  __ test(value.reg(), Immediate(kSmiTagMask));
+  destination()->false_target()->Branch(equal);
+  // It is a heap object - get map.
+  Result temp = allocator()->Allocate();
+  ASSERT(temp.is_valid());
+  // Check if the object is a JS array or not.
+  __ CmpObjectType(value.reg(), JS_ARRAY_TYPE, temp.reg());
+  value.Unuse();
+  temp.Unuse();
+  destination()->Split(equal);
+}
+
+
+void CodeGenerator::GenerateIsConstructCall(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 0);
+
+  // Get the frame pointer for the calling frame.
+  Result fp = allocator()->Allocate();
+  __ mov(fp.reg(), Operand(ebp, StandardFrameConstants::kCallerFPOffset));
+
+  // Skip the arguments adaptor frame if it exists.
+  Label check_frame_marker;
+  __ cmp(Operand(fp.reg(), StandardFrameConstants::kContextOffset),
+         Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ j(not_equal, &check_frame_marker);
+  __ mov(fp.reg(), Operand(fp.reg(), StandardFrameConstants::kCallerFPOffset));
+
+  // Check the marker in the calling frame.
+  __ bind(&check_frame_marker);
+  __ cmp(Operand(fp.reg(), StandardFrameConstants::kMarkerOffset),
+         Immediate(Smi::FromInt(StackFrame::CONSTRUCT)));
+  fp.Unuse();
+  destination()->Split(equal);
+}
+
+
+void CodeGenerator::GenerateArgumentsLength(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 0);
+  // ArgumentsAccessStub takes the parameter count as an input argument
+  // in register eax.  Create a constant result for it.
+  Result count(Handle<Smi>(Smi::FromInt(scope_->num_parameters())));
+  // Call the shared stub to get to the arguments.length.
+  ArgumentsAccessStub stub(ArgumentsAccessStub::READ_LENGTH);
+  Result result = frame_->CallStub(&stub, &count);
+  frame_->Push(&result);
+}
+
+
+void CodeGenerator::GenerateClassOf(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+  JumpTarget leave, null, function, non_function_constructor;
+  Load(args->at(0));  // Load the object.
+  Result obj = frame_->Pop();
+  obj.ToRegister();
+  frame_->Spill(obj.reg());
+
+  // If the object is a smi, we return null.
+  __ test(obj.reg(), Immediate(kSmiTagMask));
+  null.Branch(zero);
+
+  // Check that the object is a JS object but take special care of JS
+  // functions to make sure they have 'Function' as their class.
+  { Result tmp = allocator()->Allocate();
+    __ mov(obj.reg(), FieldOperand(obj.reg(), HeapObject::kMapOffset));
+    __ movzx_b(tmp.reg(), FieldOperand(obj.reg(), Map::kInstanceTypeOffset));
+    __ cmp(tmp.reg(), FIRST_JS_OBJECT_TYPE);
+    null.Branch(less);
+
+    // As long as JS_FUNCTION_TYPE is the last instance type and it is
+    // right after LAST_JS_OBJECT_TYPE, we can avoid checking for
+    // LAST_JS_OBJECT_TYPE.
+    ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
+    ASSERT(JS_FUNCTION_TYPE == LAST_JS_OBJECT_TYPE + 1);
+    __ cmp(tmp.reg(), JS_FUNCTION_TYPE);
+    function.Branch(equal);
+  }
+
+  // Check if the constructor in the map is a function.
+  { Result tmp = allocator()->Allocate();
+    __ mov(obj.reg(), FieldOperand(obj.reg(), Map::kConstructorOffset));
+    __ CmpObjectType(obj.reg(), JS_FUNCTION_TYPE, tmp.reg());
+    non_function_constructor.Branch(not_equal);
+  }
+
+  // The map register now contains the constructor function. Grab the
+  // instance class name from there.
+  __ mov(obj.reg(),
+         FieldOperand(obj.reg(), JSFunction::kSharedFunctionInfoOffset));
+  __ mov(obj.reg(),
+         FieldOperand(obj.reg(), SharedFunctionInfo::kInstanceClassNameOffset));
+  frame_->Push(&obj);
+  leave.Jump();
+
+  // Functions have class 'Function'.
+  function.Bind();
+  frame_->Push(Factory::function_class_symbol());
+  leave.Jump();
+
+  // Objects with a non-function constructor have class 'Object'.
+  non_function_constructor.Bind();
+  frame_->Push(Factory::Object_symbol());
+  leave.Jump();
+
+  // Non-JS objects have class null.
+  null.Bind();
+  frame_->Push(Factory::null_value());
+
+  // All done.
+  leave.Bind();
+}
+
+
+void CodeGenerator::GenerateValueOf(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+  JumpTarget leave;
+  Load(args->at(0));  // Load the object.
+  frame_->Dup();
+  Result object = frame_->Pop();
+  object.ToRegister();
+  ASSERT(object.is_valid());
+  // if (object->IsSmi()) return object.
+  __ test(object.reg(), Immediate(kSmiTagMask));
+  leave.Branch(zero, taken);
+  // It is a heap object - get map.
+  Result temp = allocator()->Allocate();
+  ASSERT(temp.is_valid());
+  // if (!object->IsJSValue()) return object.
+  __ CmpObjectType(object.reg(), JS_VALUE_TYPE, temp.reg());
+  leave.Branch(not_equal, not_taken);
+  __ mov(temp.reg(), FieldOperand(object.reg(), JSValue::kValueOffset));
+  object.Unuse();
+  frame_->SetElementAt(0, &temp);
+  leave.Bind();
+}
+
+
+void CodeGenerator::GenerateSetValueOf(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 2);
+  JumpTarget leave;
+  Load(args->at(0));  // Load the object.
+  Load(args->at(1));  // Load the value.
+  Result value = frame_->Pop();
+  Result object = frame_->Pop();
+  value.ToRegister();
+  object.ToRegister();
+
+  // if (object->IsSmi()) return value.
+  __ test(object.reg(), Immediate(kSmiTagMask));
+  leave.Branch(zero, &value, taken);
+
+  // It is a heap object - get its map.
+  Result scratch = allocator_->Allocate();
+  ASSERT(scratch.is_valid());
+  // if (!object->IsJSValue()) return value.
+  __ CmpObjectType(object.reg(), JS_VALUE_TYPE, scratch.reg());
+  leave.Branch(not_equal, &value, not_taken);
+
+  // Store the value.
+  __ mov(FieldOperand(object.reg(), JSValue::kValueOffset), value.reg());
+  // Update the write barrier.  Save the value as it will be
+  // overwritten by the write barrier code and is needed afterward.
+  Result duplicate_value = allocator_->Allocate();
+  ASSERT(duplicate_value.is_valid());
+  __ mov(duplicate_value.reg(), value.reg());
+  // The object register is also overwritten by the write barrier and
+  // possibly aliased in the frame.
+  frame_->Spill(object.reg());
+  __ RecordWrite(object.reg(), JSValue::kValueOffset, duplicate_value.reg(),
+                 scratch.reg());
+  object.Unuse();
+  scratch.Unuse();
+  duplicate_value.Unuse();
+
+  // Leave.
+  leave.Bind(&value);
+  frame_->Push(&value);
+}
+
+
+void CodeGenerator::GenerateArgumentsAccess(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+
+  // ArgumentsAccessStub expects the key in edx and the formal
+  // parameter count in eax.
+  Load(args->at(0));
+  Result key = frame_->Pop();
+  // Explicitly create a constant result.
+  Result count(Handle<Smi>(Smi::FromInt(scope_->num_parameters())));
+  // Call the shared stub to get to arguments[key].
+  ArgumentsAccessStub stub(ArgumentsAccessStub::READ_ELEMENT);
+  Result result = frame_->CallStub(&stub, &key, &count);
+  frame_->Push(&result);
+}
+
+
+void CodeGenerator::GenerateObjectEquals(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 2);
+
+  // Load the two objects into registers and perform the comparison.
+  Load(args->at(0));
+  Load(args->at(1));
+  Result right = frame_->Pop();
+  Result left = frame_->Pop();
+  right.ToRegister();
+  left.ToRegister();
+  __ cmp(right.reg(), Operand(left.reg()));
+  right.Unuse();
+  left.Unuse();
+  destination()->Split(equal);
+}
+
+
+void CodeGenerator::GenerateGetFramePointer(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 0);
+  ASSERT(kSmiTag == 0);  // EBP value is aligned, so it should look like Smi.
+  Result ebp_as_smi = allocator_->Allocate();
+  ASSERT(ebp_as_smi.is_valid());
+  __ mov(ebp_as_smi.reg(), Operand(ebp));
+  frame_->Push(&ebp_as_smi);
+}
+
+
+void CodeGenerator::GenerateRandomPositiveSmi(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 0);
+  frame_->SpillAll();
+
+  // Make sure the frame is aligned like the OS expects.
+  static const int kFrameAlignment = OS::ActivationFrameAlignment();
+  if (kFrameAlignment > 0) {
+    ASSERT(IsPowerOf2(kFrameAlignment));
+    __ mov(edi, Operand(esp));  // Save in callee-saved register.
+    __ and_(esp, -kFrameAlignment);
+  }
+
+  // Call V8::RandomPositiveSmi().
+  __ call(FUNCTION_ADDR(V8::RandomPositiveSmi), RelocInfo::RUNTIME_ENTRY);
+
+  // Restore stack pointer from callee-saved register edi.
+  if (kFrameAlignment > 0) {
+    __ mov(esp, Operand(edi));
+  }
+
+  Result result = allocator_->Allocate(eax);
+  frame_->Push(&result);
+}
+
+
+void CodeGenerator::GenerateFastMathOp(MathOp op, ZoneList<Expression*>* args) {
+  JumpTarget done;
+  JumpTarget call_runtime;
+  ASSERT(args->length() == 1);
+
+  // Load number and duplicate it.
+  Load(args->at(0));
+  frame_->Dup();
+
+  // Get the number into an unaliased register and load it onto the
+  // floating point stack still leaving one copy on the frame.
+  Result number = frame_->Pop();
+  number.ToRegister();
+  frame_->Spill(number.reg());
+  FloatingPointHelper::LoadFloatOperand(masm_, number.reg());
+  number.Unuse();
+
+  // Perform the operation on the number.
+  switch (op) {
+    case SIN:
+      __ fsin();
+      break;
+    case COS:
+      __ fcos();
+      break;
+  }
+
+  // Go slow case if argument to operation is out of range.
+  Result eax_reg = allocator_->Allocate(eax);
+  ASSERT(eax_reg.is_valid());
+  __ fnstsw_ax();
+  __ sahf();
+  eax_reg.Unuse();
+  call_runtime.Branch(parity_even, not_taken);
+
+  // Allocate heap number for result if possible.
+  Result scratch1 = allocator()->Allocate();
+  Result scratch2 = allocator()->Allocate();
+  Result heap_number = allocator()->Allocate();
+  FloatingPointHelper::AllocateHeapNumber(masm_,
+                                          call_runtime.entry_label(),
+                                          scratch1.reg(),
+                                          scratch2.reg(),
+                                          heap_number.reg());
+  scratch1.Unuse();
+  scratch2.Unuse();
+
+  // Store the result in the allocated heap number.
+  __ fstp_d(FieldOperand(heap_number.reg(), HeapNumber::kValueOffset));
+  // Replace the extra copy of the argument with the result.
+  frame_->SetElementAt(0, &heap_number);
+  done.Jump();
+
+  call_runtime.Bind();
+  // Free ST(0) which was not popped before calling into the runtime.
+  __ ffree(0);
+  Result answer;
+  switch (op) {
+    case SIN:
+      answer = frame_->CallRuntime(Runtime::kMath_sin, 1);
+      break;
+    case COS:
+      answer = frame_->CallRuntime(Runtime::kMath_cos, 1);
+      break;
+  }
+  frame_->Push(&answer);
+  done.Bind();
+}
+
+
+void CodeGenerator::VisitCallRuntime(CallRuntime* node) {
+  if (CheckForInlineRuntimeCall(node)) {
+    return;
+  }
+
+  ZoneList<Expression*>* args = node->arguments();
+  Comment cmnt(masm_, "[ CallRuntime");
+  Runtime::Function* function = node->function();
+
+  if (function == NULL) {
+    // Prepare stack for calling JS runtime function.
+    frame_->Push(node->name());
+    // Push the builtins object found in the current global object.
+    Result temp = allocator()->Allocate();
+    ASSERT(temp.is_valid());
+    __ mov(temp.reg(), GlobalObject());
+    __ mov(temp.reg(), FieldOperand(temp.reg(), GlobalObject::kBuiltinsOffset));
+    frame_->Push(&temp);
+  }
+
+  // Push the arguments ("left-to-right").
+  int arg_count = args->length();
+  for (int i = 0; i < arg_count; i++) {
+    Load(args->at(i));
+  }
+
+  if (function == NULL) {
+    // Call the JS runtime function.
+    Result answer = frame_->CallCallIC(RelocInfo::CODE_TARGET,
+                                       arg_count,
+                                       loop_nesting_);
+    frame_->RestoreContextRegister();
+    frame_->SetElementAt(0, &answer);
+  } else {
+    // Call the C runtime function.
+    Result answer = frame_->CallRuntime(function, arg_count);
+    frame_->Push(&answer);
+  }
+}
+
+
+void CodeGenerator::VisitUnaryOperation(UnaryOperation* node) {
+  // Note that because of NOT and an optimization in comparison of a typeof
+  // expression to a literal string, this function can fail to leave a value
+  // on top of the frame or in the cc register.
+  Comment cmnt(masm_, "[ UnaryOperation");
+
+  Token::Value op = node->op();
+
+  if (op == Token::NOT) {
+    // Swap the true and false targets but keep the same actual label
+    // as the fall through.
+    destination()->Invert();
+    LoadCondition(node->expression(), NOT_INSIDE_TYPEOF, destination(), true);
+    // Swap the labels back.
+    destination()->Invert();
+
+  } else if (op == Token::DELETE) {
+    Property* property = node->expression()->AsProperty();
+    if (property != NULL) {
+      Load(property->obj());
+      Load(property->key());
+      Result answer = frame_->InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION, 2);
+      frame_->Push(&answer);
+      return;
+    }
+
+    Variable* variable = node->expression()->AsVariableProxy()->AsVariable();
+    if (variable != NULL) {
+      Slot* slot = variable->slot();
+      if (variable->is_global()) {
+        LoadGlobal();
+        frame_->Push(variable->name());
+        Result answer = frame_->InvokeBuiltin(Builtins::DELETE,
+                                              CALL_FUNCTION, 2);
+        frame_->Push(&answer);
+        return;
+
+      } else if (slot != NULL && slot->type() == Slot::LOOKUP) {
+        // Call the runtime to look up the context holding the named
+        // variable.  Sync the virtual frame eagerly so we can push the
+        // arguments directly into place.
+        frame_->SyncRange(0, frame_->element_count() - 1);
+        frame_->EmitPush(esi);
+        frame_->EmitPush(Immediate(variable->name()));
+        Result context = frame_->CallRuntime(Runtime::kLookupContext, 2);
+        ASSERT(context.is_register());
+        frame_->EmitPush(context.reg());
+        context.Unuse();
+        frame_->EmitPush(Immediate(variable->name()));
+        Result answer = frame_->InvokeBuiltin(Builtins::DELETE,
+                                              CALL_FUNCTION, 2);
+        frame_->Push(&answer);
+        return;
+      }
+
+      // Default: Result of deleting non-global, not dynamically
+      // introduced variables is false.
+      frame_->Push(Factory::false_value());
+
+    } else {
+      // Default: Result of deleting expressions is true.
+      Load(node->expression());  // may have side-effects
+      frame_->SetElementAt(0, Factory::true_value());
+    }
+
+  } else if (op == Token::TYPEOF) {
+    // Special case for loading the typeof expression; see comment on
+    // LoadTypeofExpression().
+    LoadTypeofExpression(node->expression());
+    Result answer = frame_->CallRuntime(Runtime::kTypeof, 1);
+    frame_->Push(&answer);
+
+  } else if (op == Token::VOID) {
+    Expression* expression = node->expression();
+    if (expression && expression->AsLiteral() && (
+        expression->AsLiteral()->IsTrue() ||
+        expression->AsLiteral()->IsFalse() ||
+        expression->AsLiteral()->handle()->IsNumber() ||
+        expression->AsLiteral()->handle()->IsString() ||
+        expression->AsLiteral()->handle()->IsJSRegExp() ||
+        expression->AsLiteral()->IsNull())) {
+      // Omit evaluating the value of the primitive literal.
+      // It will be discarded anyway, and can have no side effect.
+      frame_->Push(Factory::undefined_value());
+    } else {
+      Load(node->expression());
+      frame_->SetElementAt(0, Factory::undefined_value());
+    }
+
+  } else {
+    Load(node->expression());
+    switch (op) {
+      case Token::SUB: {
+        bool overwrite =
+            (node->AsBinaryOperation() != NULL &&
+             node->AsBinaryOperation()->ResultOverwriteAllowed());
+        UnarySubStub stub(overwrite);
+        // TODO(1222589): remove dependency of TOS being cached inside stub
+        Result operand = frame_->Pop();
+        Result answer = frame_->CallStub(&stub, &operand);
+        frame_->Push(&answer);
+        break;
+      }
+
+      case Token::BIT_NOT: {
+        // Smi check.
+        JumpTarget smi_label;
+        JumpTarget continue_label;
+        Result operand = frame_->Pop();
+        operand.ToRegister();
+        __ test(operand.reg(), Immediate(kSmiTagMask));
+        smi_label.Branch(zero, &operand, taken);
+
+        frame_->Push(&operand);  // undo popping of TOS
+        Result answer = frame_->InvokeBuiltin(Builtins::BIT_NOT,
+                                              CALL_FUNCTION, 1);
+
+        continue_label.Jump(&answer);
+        smi_label.Bind(&answer);
+        answer.ToRegister();
+        frame_->Spill(answer.reg());
+        __ not_(answer.reg());
+        __ and_(answer.reg(), ~kSmiTagMask);  // Remove inverted smi-tag.
+        continue_label.Bind(&answer);
+        frame_->Push(&answer);
+        break;
+      }
+
+      case Token::ADD: {
+        // Smi check.
+        JumpTarget continue_label;
+        Result operand = frame_->Pop();
+        operand.ToRegister();
+        __ test(operand.reg(), Immediate(kSmiTagMask));
+        continue_label.Branch(zero, &operand, taken);
+
+        frame_->Push(&operand);
+        Result answer = frame_->InvokeBuiltin(Builtins::TO_NUMBER,
+                                              CALL_FUNCTION, 1);
+
+        continue_label.Bind(&answer);
+        frame_->Push(&answer);
+        break;
+      }
+
+      default:
+        // NOT, DELETE, TYPEOF, and VOID are handled outside the
+        // switch.
+        UNREACHABLE();
+    }
+  }
+}
+
+
+// The value in dst was optimistically incremented or decremented.  The
+// result overflowed or was not smi tagged.  Undo the operation, call
+// into the runtime to convert the argument to a number, and call the
+// specialized add or subtract stub.  The result is left in dst.
+class DeferredPrefixCountOperation: public DeferredCode {
+ public:
+  DeferredPrefixCountOperation(Register dst, bool is_increment)
+      : dst_(dst), is_increment_(is_increment) {
+    set_comment("[ DeferredCountOperation");
+  }
+
+  virtual void Generate();
+
+ private:
+  Register dst_;
+  bool is_increment_;
+};
+
+
+void DeferredPrefixCountOperation::Generate() {
+  // Undo the optimistic smi operation.
+  if (is_increment_) {
+    __ sub(Operand(dst_), Immediate(Smi::FromInt(1)));
+  } else {
+    __ add(Operand(dst_), Immediate(Smi::FromInt(1)));
+  }
+  __ push(dst_);
+  __ InvokeBuiltin(Builtins::TO_NUMBER, CALL_FUNCTION);
+  __ push(eax);
+  __ push(Immediate(Smi::FromInt(1)));
+  if (is_increment_) {
+    __ CallRuntime(Runtime::kNumberAdd, 2);
+  } else {
+    __ CallRuntime(Runtime::kNumberSub, 2);
+  }
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+}
+
+
+// The value in dst was optimistically incremented or decremented.  The
+// result overflowed or was not smi tagged.  Undo the operation and call
+// into the runtime to convert the argument to a number.  Update the
+// original value in old.  Call the specialized add or subtract stub.
+// The result is left in dst.
+class DeferredPostfixCountOperation: public DeferredCode {
+ public:
+  DeferredPostfixCountOperation(Register dst, Register old, bool is_increment)
+      : dst_(dst), old_(old), is_increment_(is_increment) {
+    set_comment("[ DeferredCountOperation");
+  }
+
+  virtual void Generate();
+
+ private:
+  Register dst_;
+  Register old_;
+  bool is_increment_;
+};
+
+
+void DeferredPostfixCountOperation::Generate() {
+  // Undo the optimistic smi operation.
+  if (is_increment_) {
+    __ sub(Operand(dst_), Immediate(Smi::FromInt(1)));
+  } else {
+    __ add(Operand(dst_), Immediate(Smi::FromInt(1)));
+  }
+  __ push(dst_);
+  __ InvokeBuiltin(Builtins::TO_NUMBER, CALL_FUNCTION);
+
+  // Save the result of ToNumber to use as the old value.
+  __ push(eax);
+
+  // Call the runtime for the addition or subtraction.
+  __ push(eax);
+  __ push(Immediate(Smi::FromInt(1)));
+  if (is_increment_) {
+    __ CallRuntime(Runtime::kNumberAdd, 2);
+  } else {
+    __ CallRuntime(Runtime::kNumberSub, 2);
+  }
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+  __ pop(old_);
+}
+
+
+void CodeGenerator::VisitCountOperation(CountOperation* node) {
+  Comment cmnt(masm_, "[ CountOperation");
+
+  bool is_postfix = node->is_postfix();
+  bool is_increment = node->op() == Token::INC;
+
+  Variable* var = node->expression()->AsVariableProxy()->AsVariable();
+  bool is_const = (var != NULL && var->mode() == Variable::CONST);
+
+  // Postfix operations need a stack slot under the reference to hold
+  // the old value while the new value is being stored.  This is so that
+  // in the case that storing the new value requires a call, the old
+  // value will be in the frame to be spilled.
+  if (is_postfix) frame_->Push(Smi::FromInt(0));
+
+  { Reference target(this, node->expression());
+    if (target.is_illegal()) {
+      // Spoof the virtual frame to have the expected height (one higher
+      // than on entry).
+      if (!is_postfix) frame_->Push(Smi::FromInt(0));
+      return;
+    }
+    target.TakeValue(NOT_INSIDE_TYPEOF);
+
+    Result new_value = frame_->Pop();
+    new_value.ToRegister();
+
+    Result old_value;  // Only allocated in the postfix case.
+    if (is_postfix) {
+      // Allocate a temporary to preserve the old value.
+      old_value = allocator_->Allocate();
+      ASSERT(old_value.is_valid());
+      __ mov(old_value.reg(), new_value.reg());
+    }
+    // Ensure the new value is writable.
+    frame_->Spill(new_value.reg());
+
+    // In order to combine the overflow and the smi tag check, we need
+    // to be able to allocate a byte register.  We attempt to do so
+    // without spilling.  If we fail, we will generate separate overflow
+    // and smi tag checks.
+    //
+    // We allocate and clear the temporary byte register before
+    // performing the count operation since clearing the register using
+    // xor will clear the overflow flag.
+    Result tmp = allocator_->AllocateByteRegisterWithoutSpilling();
+    if (tmp.is_valid()) {
+      __ Set(tmp.reg(), Immediate(0));
+    }
+
+    DeferredCode* deferred = NULL;
+    if (is_postfix) {
+      deferred = new DeferredPostfixCountOperation(new_value.reg(),
+                                                   old_value.reg(),
+                                                   is_increment);
+    } else {
+      deferred = new DeferredPrefixCountOperation(new_value.reg(),
+                                                  is_increment);
+    }
+
+    if (is_increment) {
+      __ add(Operand(new_value.reg()), Immediate(Smi::FromInt(1)));
+    } else {
+      __ sub(Operand(new_value.reg()), Immediate(Smi::FromInt(1)));
+    }
+
+    // If the count operation didn't overflow and the result is a valid
+    // smi, we're done. Otherwise, we jump to the deferred slow-case
+    // code.
+    if (tmp.is_valid()) {
+      // We combine the overflow and the smi tag check if we could
+      // successfully allocate a temporary byte register.
+      __ setcc(overflow, tmp.reg());
+      __ or_(Operand(tmp.reg()), new_value.reg());
+      __ test(tmp.reg(), Immediate(kSmiTagMask));
+      tmp.Unuse();
+      deferred->Branch(not_zero);
+    } else {
+      // Otherwise we test separately for overflow and smi tag.
+      deferred->Branch(overflow);
+      __ test(new_value.reg(), Immediate(kSmiTagMask));
+      deferred->Branch(not_zero);
+    }
+    deferred->BindExit();
+
+    // Postfix: store the old value in the allocated slot under the
+    // reference.
+    if (is_postfix) frame_->SetElementAt(target.size(), &old_value);
+
+    frame_->Push(&new_value);
+    // Non-constant: update the reference.
+    if (!is_const) target.SetValue(NOT_CONST_INIT);
+  }
+
+  // Postfix: drop the new value and use the old.
+  if (is_postfix) frame_->Drop();
+}
+
+
+void CodeGenerator::VisitBinaryOperation(BinaryOperation* node) {
+  // Note that due to an optimization in comparison operations (typeof
+  // compared to a string literal), we can evaluate a binary expression such
+  // as AND or OR and not leave a value on the frame or in the cc register.
+  Comment cmnt(masm_, "[ BinaryOperation");
+  Token::Value op = node->op();
+
+  // According to ECMA-262 section 11.11, page 58, the binary logical
+  // operators must yield the result of one of the two expressions
+  // before any ToBoolean() conversions. This means that the value
+  // produced by a && or || operator is not necessarily a boolean.
+
+  // NOTE: If the left hand side produces a materialized value (not
+  // control flow), we force the right hand side to do the same. This
+  // is necessary because we assume that if we get control flow on the
+  // last path out of an expression we got it on all paths.
+  if (op == Token::AND) {
+    JumpTarget is_true;
+    ControlDestination dest(&is_true, destination()->false_target(), true);
+    LoadCondition(node->left(), NOT_INSIDE_TYPEOF, &dest, false);
+
+    if (dest.false_was_fall_through()) {
+      // The current false target was used as the fall-through.  If
+      // there are no dangling jumps to is_true then the left
+      // subexpression was unconditionally false.  Otherwise we have
+      // paths where we do have to evaluate the right subexpression.
+      if (is_true.is_linked()) {
+        // We need to compile the right subexpression.  If the jump to
+        // the current false target was a forward jump then we have a
+        // valid frame, we have just bound the false target, and we
+        // have to jump around the code for the right subexpression.
+        if (has_valid_frame()) {
+          destination()->false_target()->Unuse();
+          destination()->false_target()->Jump();
+        }
+        is_true.Bind();
+        // The left subexpression compiled to control flow, so the
+        // right one is free to do so as well.
+        LoadCondition(node->right(), NOT_INSIDE_TYPEOF, destination(), false);
+      } else {
+        // We have actually just jumped to or bound the current false
+        // target but the current control destination is not marked as
+        // used.
+        destination()->Use(false);
+      }
+
+    } else if (dest.is_used()) {
+      // The left subexpression compiled to control flow (and is_true
+      // was just bound), so the right is free to do so as well.
+      LoadCondition(node->right(), NOT_INSIDE_TYPEOF, destination(), false);
+
+    } else {
+      // We have a materialized value on the frame, so we exit with
+      // one on all paths.  There are possibly also jumps to is_true
+      // from nested subexpressions.
+      JumpTarget pop_and_continue;
+      JumpTarget exit;
+
+      // Avoid popping the result if it converts to 'false' using the
+      // standard ToBoolean() conversion as described in ECMA-262,
+      // section 9.2, page 30.
+      //
+      // Duplicate the TOS value. The duplicate will be popped by
+      // ToBoolean.
+      frame_->Dup();
+      ControlDestination dest(&pop_and_continue, &exit, true);
+      ToBoolean(&dest);
+
+      // Pop the result of evaluating the first part.
+      frame_->Drop();
+
+      // Compile right side expression.
+      is_true.Bind();
+      Load(node->right());
+
+      // Exit (always with a materialized value).
+      exit.Bind();
+    }
+
+  } else if (op == Token::OR) {
+    JumpTarget is_false;
+    ControlDestination dest(destination()->true_target(), &is_false, false);
+    LoadCondition(node->left(), NOT_INSIDE_TYPEOF, &dest, false);
+
+    if (dest.true_was_fall_through()) {
+      // The current true target was used as the fall-through.  If
+      // there are no dangling jumps to is_false then the left
+      // subexpression was unconditionally true.  Otherwise we have
+      // paths where we do have to evaluate the right subexpression.
+      if (is_false.is_linked()) {
+        // We need to compile the right subexpression.  If the jump to
+        // the current true target was a forward jump then we have a
+        // valid frame, we have just bound the true target, and we
+        // have to jump around the code for the right subexpression.
+        if (has_valid_frame()) {
+          destination()->true_target()->Unuse();
+          destination()->true_target()->Jump();
+        }
+        is_false.Bind();
+        // The left subexpression compiled to control flow, so the
+        // right one is free to do so as well.
+        LoadCondition(node->right(), NOT_INSIDE_TYPEOF, destination(), false);
+      } else {
+        // We have just jumped to or bound the current true target but
+        // the current control destination is not marked as used.
+        destination()->Use(true);
+      }
+
+    } else if (dest.is_used()) {
+      // The left subexpression compiled to control flow (and is_false
+      // was just bound), so the right is free to do so as well.
+      LoadCondition(node->right(), NOT_INSIDE_TYPEOF, destination(), false);
+
+    } else {
+      // We have a materialized value on the frame, so we exit with
+      // one on all paths.  There are possibly also jumps to is_false
+      // from nested subexpressions.
+      JumpTarget pop_and_continue;
+      JumpTarget exit;
+
+      // Avoid popping the result if it converts to 'true' using the
+      // standard ToBoolean() conversion as described in ECMA-262,
+      // section 9.2, page 30.
+      //
+      // Duplicate the TOS value. The duplicate will be popped by
+      // ToBoolean.
+      frame_->Dup();
+      ControlDestination dest(&exit, &pop_and_continue, false);
+      ToBoolean(&dest);
+
+      // Pop the result of evaluating the first part.
+      frame_->Drop();
+
+      // Compile right side expression.
+      is_false.Bind();
+      Load(node->right());
+
+      // Exit (always with a materialized value).
+      exit.Bind();
+    }
+
+  } else {
+    // NOTE: The code below assumes that the slow cases (calls to runtime)
+    // never return a constant/immutable object.
+    OverwriteMode overwrite_mode = NO_OVERWRITE;
+    if (node->left()->AsBinaryOperation() != NULL &&
+        node->left()->AsBinaryOperation()->ResultOverwriteAllowed()) {
+      overwrite_mode = OVERWRITE_LEFT;
+    } else if (node->right()->AsBinaryOperation() != NULL &&
+               node->right()->AsBinaryOperation()->ResultOverwriteAllowed()) {
+      overwrite_mode = OVERWRITE_RIGHT;
+    }
+
+    Load(node->left());
+    Load(node->right());
+    GenericBinaryOperation(node->op(), node->type(), overwrite_mode);
+  }
+}
+
+
+void CodeGenerator::VisitThisFunction(ThisFunction* node) {
+  frame_->PushFunction();
+}
+
+
+void CodeGenerator::VisitCompareOperation(CompareOperation* node) {
+  Comment cmnt(masm_, "[ CompareOperation");
+
+  // Get the expressions from the node.
+  Expression* left = node->left();
+  Expression* right = node->right();
+  Token::Value op = node->op();
+  // To make typeof testing for natives implemented in JavaScript really
+  // efficient, we generate special code for expressions of the form:
+  // 'typeof <expression> == <string>'.
+  UnaryOperation* operation = left->AsUnaryOperation();
+  if ((op == Token::EQ || op == Token::EQ_STRICT) &&
+      (operation != NULL && operation->op() == Token::TYPEOF) &&
+      (right->AsLiteral() != NULL &&
+       right->AsLiteral()->handle()->IsString())) {
+    Handle<String> check(String::cast(*right->AsLiteral()->handle()));
+
+    // Load the operand and move it to a register.
+    LoadTypeofExpression(operation->expression());
+    Result answer = frame_->Pop();
+    answer.ToRegister();
+
+    if (check->Equals(Heap::number_symbol())) {
+      __ test(answer.reg(), Immediate(kSmiTagMask));
+      destination()->true_target()->Branch(zero);
+      frame_->Spill(answer.reg());
+      __ mov(answer.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
+      __ cmp(answer.reg(), Factory::heap_number_map());
+      answer.Unuse();
+      destination()->Split(equal);
+
+    } else if (check->Equals(Heap::string_symbol())) {
+      __ test(answer.reg(), Immediate(kSmiTagMask));
+      destination()->false_target()->Branch(zero);
+
+      // It can be an undetectable string object.
+      Result temp = allocator()->Allocate();
+      ASSERT(temp.is_valid());
+      __ mov(temp.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
+      __ movzx_b(temp.reg(), FieldOperand(temp.reg(), Map::kBitFieldOffset));
+      __ test(temp.reg(), Immediate(1 << Map::kIsUndetectable));
+      destination()->false_target()->Branch(not_zero);
+      __ mov(temp.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
+      __ movzx_b(temp.reg(),
+                 FieldOperand(temp.reg(), Map::kInstanceTypeOffset));
+      __ cmp(temp.reg(), FIRST_NONSTRING_TYPE);
+      temp.Unuse();
+      answer.Unuse();
+      destination()->Split(less);
+
+    } else if (check->Equals(Heap::boolean_symbol())) {
+      __ cmp(answer.reg(), Factory::true_value());
+      destination()->true_target()->Branch(equal);
+      __ cmp(answer.reg(), Factory::false_value());
+      answer.Unuse();
+      destination()->Split(equal);
+
+    } else if (check->Equals(Heap::undefined_symbol())) {
+      __ cmp(answer.reg(), Factory::undefined_value());
+      destination()->true_target()->Branch(equal);
+
+      __ test(answer.reg(), Immediate(kSmiTagMask));
+      destination()->false_target()->Branch(zero);
+
+      // It can be an undetectable object.
+      frame_->Spill(answer.reg());
+      __ mov(answer.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
+      __ movzx_b(answer.reg(),
+                 FieldOperand(answer.reg(), Map::kBitFieldOffset));
+      __ test(answer.reg(), Immediate(1 << Map::kIsUndetectable));
+      answer.Unuse();
+      destination()->Split(not_zero);
+
+    } else if (check->Equals(Heap::function_symbol())) {
+      __ test(answer.reg(), Immediate(kSmiTagMask));
+      destination()->false_target()->Branch(zero);
+      frame_->Spill(answer.reg());
+      __ CmpObjectType(answer.reg(), JS_FUNCTION_TYPE, answer.reg());
+      answer.Unuse();
+      destination()->Split(equal);
+
+    } else if (check->Equals(Heap::object_symbol())) {
+      __ test(answer.reg(), Immediate(kSmiTagMask));
+      destination()->false_target()->Branch(zero);
+      __ cmp(answer.reg(), Factory::null_value());
+      destination()->true_target()->Branch(equal);
+
+      // It can be an undetectable object.
+      Result map = allocator()->Allocate();
+      ASSERT(map.is_valid());
+      __ mov(map.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
+      __ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kBitFieldOffset));
+      __ test(map.reg(), Immediate(1 << Map::kIsUndetectable));
+      destination()->false_target()->Branch(not_zero);
+      __ mov(map.reg(), FieldOperand(answer.reg(), HeapObject::kMapOffset));
+      __ movzx_b(map.reg(), FieldOperand(map.reg(), Map::kInstanceTypeOffset));
+      __ cmp(map.reg(), FIRST_JS_OBJECT_TYPE);
+      destination()->false_target()->Branch(less);
+      __ cmp(map.reg(), LAST_JS_OBJECT_TYPE);
+      answer.Unuse();
+      map.Unuse();
+      destination()->Split(less_equal);
+    } else {
+      // Uncommon case: typeof testing against a string literal that is
+      // never returned from the typeof operator.
+      answer.Unuse();
+      destination()->Goto(false);
+    }
+    return;
+  }
+
+  Condition cc = no_condition;
+  bool strict = false;
+  switch (op) {
+    case Token::EQ_STRICT:
+      strict = true;
+      // Fall through
+    case Token::EQ:
+      cc = equal;
+      break;
+    case Token::LT:
+      cc = less;
+      break;
+    case Token::GT:
+      cc = greater;
+      break;
+    case Token::LTE:
+      cc = less_equal;
+      break;
+    case Token::GTE:
+      cc = greater_equal;
+      break;
+    case Token::IN: {
+      Load(left);
+      Load(right);
+      Result answer = frame_->InvokeBuiltin(Builtins::IN, CALL_FUNCTION, 2);
+      frame_->Push(&answer);  // push the result
+      return;
+    }
+    case Token::INSTANCEOF: {
+      Load(left);
+      Load(right);
+      InstanceofStub stub;
+      Result answer = frame_->CallStub(&stub, 2);
+      answer.ToRegister();
+      __ test(answer.reg(), Operand(answer.reg()));
+      answer.Unuse();
+      destination()->Split(zero);
+      return;
+    }
+    default:
+      UNREACHABLE();
+  }
+  Load(left);
+  Load(right);
+  Comparison(cc, strict, destination());
+}
+
+
+#ifdef DEBUG
+bool CodeGenerator::HasValidEntryRegisters() {
+  return (allocator()->count(eax) == (frame()->is_used(eax) ? 1 : 0))
+      && (allocator()->count(ebx) == (frame()->is_used(ebx) ? 1 : 0))
+      && (allocator()->count(ecx) == (frame()->is_used(ecx) ? 1 : 0))
+      && (allocator()->count(edx) == (frame()->is_used(edx) ? 1 : 0))
+      && (allocator()->count(edi) == (frame()->is_used(edi) ? 1 : 0));
+}
+#endif
+
+
+// Emit a LoadIC call to get the value from receiver and leave it in
+// dst.  The receiver register is restored after the call.
+class DeferredReferenceGetNamedValue: public DeferredCode {
+ public:
+  DeferredReferenceGetNamedValue(Register dst,
+                                 Register receiver,
+                                 Handle<String> name)
+      : dst_(dst), receiver_(receiver),  name_(name) {
+    set_comment("[ DeferredReferenceGetNamedValue");
+  }
+
+  virtual void Generate();
+
+  Label* patch_site() { return &patch_site_; }
+
+ private:
+  Label patch_site_;
+  Register dst_;
+  Register receiver_;
+  Handle<String> name_;
+};
+
+
+void DeferredReferenceGetNamedValue::Generate() {
+  __ push(receiver_);
+  __ Set(ecx, Immediate(name_));
+  Handle<Code> ic(Builtins::builtin(Builtins::LoadIC_Initialize));
+  __ call(ic, RelocInfo::CODE_TARGET);
+  // The call must be followed by a test eax instruction to indicate
+  // that the inobject property case was inlined.
+  //
+  // Store the delta to the map check instruction here in the test
+  // instruction.  Use masm_-> instead of the __ macro since the
+  // latter can't return a value.
+  int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(patch_site());
+  // Here we use masm_-> instead of the __ macro because this is the
+  // instruction that gets patched and coverage code gets in the way.
+  masm_->test(eax, Immediate(-delta_to_patch_site));
+  __ IncrementCounter(&Counters::named_load_inline_miss, 1);
+
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+  __ pop(receiver_);
+}
+
+
+class DeferredReferenceGetKeyedValue: public DeferredCode {
+ public:
+  explicit DeferredReferenceGetKeyedValue(Register dst,
+                                          Register receiver,
+                                          Register key,
+                                          bool is_global)
+      : dst_(dst), receiver_(receiver), key_(key), is_global_(is_global) {
+    set_comment("[ DeferredReferenceGetKeyedValue");
+  }
+
+  virtual void Generate();
+
+  Label* patch_site() { return &patch_site_; }
+
+ private:
+  Label patch_site_;
+  Register dst_;
+  Register receiver_;
+  Register key_;
+  bool is_global_;
+};
+
+
+void DeferredReferenceGetKeyedValue::Generate() {
+  __ push(receiver_);  // First IC argument.
+  __ push(key_);       // Second IC argument.
+
+  // Calculate the delta from the IC call instruction to the map check
+  // cmp instruction in the inlined version.  This delta is stored in
+  // a test(eax, delta) instruction after the call so that we can find
+  // it in the IC initialization code and patch the cmp instruction.
+  // This means that we cannot allow test instructions after calls to
+  // KeyedLoadIC stubs in other places.
+  Handle<Code> ic(Builtins::builtin(Builtins::KeyedLoadIC_Initialize));
+  RelocInfo::Mode mode = is_global_
+                         ? RelocInfo::CODE_TARGET_CONTEXT
+                         : RelocInfo::CODE_TARGET;
+  __ call(ic, mode);
+  // The delta from the start of the map-compare instruction to the
+  // test instruction.  We use masm_-> directly here instead of the __
+  // macro because the macro sometimes uses macro expansion to turn
+  // into something that can't return a value.  This is encountered
+  // when doing generated code coverage tests.
+  int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(patch_site());
+  // Here we use masm_-> instead of the __ macro because this is the
+  // instruction that gets patched and coverage code gets in the way.
+  masm_->test(eax, Immediate(-delta_to_patch_site));
+  __ IncrementCounter(&Counters::keyed_load_inline_miss, 1);
+
+  if (!dst_.is(eax)) __ mov(dst_, eax);
+  __ pop(key_);
+  __ pop(receiver_);
+}
+
+
+class DeferredReferenceSetKeyedValue: public DeferredCode {
+ public:
+  DeferredReferenceSetKeyedValue(Register value,
+                                 Register key,
+                                 Register receiver)
+      : value_(value), key_(key), receiver_(receiver) {
+    set_comment("[ DeferredReferenceSetKeyedValue");
+  }
+
+  virtual void Generate();
+
+  Label* patch_site() { return &patch_site_; }
+
+ private:
+  Register value_;
+  Register key_;
+  Register receiver_;
+  Label patch_site_;
+};
+
+
+void DeferredReferenceSetKeyedValue::Generate() {
+  __ IncrementCounter(&Counters::keyed_store_inline_miss, 1);
+  // Push receiver and key arguments on the stack.
+  __ push(receiver_);
+  __ push(key_);
+  // Move value argument to eax as expected by the IC stub.
+  if (!value_.is(eax)) __ mov(eax, value_);
+  // Call the IC stub.
+  Handle<Code> ic(Builtins::builtin(Builtins::KeyedStoreIC_Initialize));
+  __ call(ic, RelocInfo::CODE_TARGET);
+  // The delta from the start of the map-compare instruction to the
+  // test instruction.  We use masm_-> directly here instead of the
+  // __ macro because the macro sometimes uses macro expansion to turn
+  // into something that can't return a value.  This is encountered
+  // when doing generated code coverage tests.
+  int delta_to_patch_site = masm_->SizeOfCodeGeneratedSince(patch_site());
+  // Here we use masm_-> instead of the __ macro because this is the
+  // instruction that gets patched and coverage code gets in the way.
+  masm_->test(eax, Immediate(-delta_to_patch_site));
+  // Restore value (returned from store IC), key and receiver
+  // registers.
+  if (!value_.is(eax)) __ mov(value_, eax);
+  __ pop(key_);
+  __ pop(receiver_);
+}
+
+
+#undef __
+#define __ ACCESS_MASM(masm)
+
+
+Handle<String> Reference::GetName() {
+  ASSERT(type_ == NAMED);
+  Property* property = expression_->AsProperty();
+  if (property == NULL) {
+    // Global variable reference treated as a named property reference.
+    VariableProxy* proxy = expression_->AsVariableProxy();
+    ASSERT(proxy->AsVariable() != NULL);
+    ASSERT(proxy->AsVariable()->is_global());
+    return proxy->name();
+  } else {
+    Literal* raw_name = property->key()->AsLiteral();
+    ASSERT(raw_name != NULL);
+    return Handle<String>(String::cast(*raw_name->handle()));
+  }
+}
+
+
+void Reference::GetValue(TypeofState typeof_state) {
+  ASSERT(!cgen_->in_spilled_code());
+  ASSERT(cgen_->HasValidEntryRegisters());
+  ASSERT(!is_illegal());
+  MacroAssembler* masm = cgen_->masm();
+
+  // Record the source position for the property load.
+  Property* property = expression_->AsProperty();
+  if (property != NULL) {
+    cgen_->CodeForSourcePosition(property->position());
+  }
+
+  switch (type_) {
+    case SLOT: {
+      Comment cmnt(masm, "[ Load from Slot");
+      Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
+      ASSERT(slot != NULL);
+      cgen_->LoadFromSlotCheckForArguments(slot, typeof_state);
+      break;
+    }
+
+    case NAMED: {
+      // TODO(1241834): Make sure that it is safe to ignore the
+      // distinction between expressions in a typeof and not in a
+      // typeof. If there is a chance that reference errors can be
+      // thrown below, we must distinguish between the two kinds of
+      // loads (typeof expression loads must not throw a reference
+      // error).
+      Variable* var = expression_->AsVariableProxy()->AsVariable();
+      bool is_global = var != NULL;
+      ASSERT(!is_global || var->is_global());
+
+      // Do not inline the inobject property case for loads from the global
+      // object.  Also do not inline for unoptimized code.  This saves time
+      // in the code generator.  Unoptimized code is toplevel code or code
+      // that is not in a loop.
+      if (is_global ||
+          cgen_->scope()->is_global_scope() ||
+          cgen_->loop_nesting() == 0) {
+        Comment cmnt(masm, "[ Load from named Property");
+        cgen_->frame()->Push(GetName());
+
+        RelocInfo::Mode mode = is_global
+                               ? RelocInfo::CODE_TARGET_CONTEXT
+                               : RelocInfo::CODE_TARGET;
+        Result answer = cgen_->frame()->CallLoadIC(mode);
+        // A test eax instruction following the call signals that the
+        // inobject property case was inlined.  Ensure that there is not
+        // a test eax instruction here.
+        __ nop();
+        cgen_->frame()->Push(&answer);
+      } else {
+        // Inline the inobject property case.
+        Comment cmnt(masm, "[ Inlined named property load");
+        Result receiver = cgen_->frame()->Pop();
+        receiver.ToRegister();
+
+        Result value = cgen_->allocator()->Allocate();
+        ASSERT(value.is_valid());
+        DeferredReferenceGetNamedValue* deferred =
+            new DeferredReferenceGetNamedValue(value.reg(),
+                                               receiver.reg(),
+                                               GetName());
+
+        // Check that the receiver is a heap object.
+        __ test(receiver.reg(), Immediate(kSmiTagMask));
+        deferred->Branch(zero);
+
+        __ bind(deferred->patch_site());
+        // This is the map check instruction that will be patched (so we can't
+        // use the double underscore macro that may insert instructions).
+        // Initially use an invalid map to force a failure.
+        masm->cmp(FieldOperand(receiver.reg(), HeapObject::kMapOffset),
+                  Immediate(Factory::null_value()));
+        // This branch is always a forwards branch so it's always a fixed
+        // size which allows the assert below to succeed and patching to work.
+        deferred->Branch(not_equal);
+
+        // The delta from the patch label to the load offset must be
+        // statically known.
+        ASSERT(masm->SizeOfCodeGeneratedSince(deferred->patch_site()) ==
+               LoadIC::kOffsetToLoadInstruction);
+        // The initial (invalid) offset has to be large enough to force
+        // a 32-bit instruction encoding to allow patching with an
+        // arbitrary offset.  Use kMaxInt (minus kHeapObjectTag).
+        int offset = kMaxInt;
+        masm->mov(value.reg(), FieldOperand(receiver.reg(), offset));
+
+        __ IncrementCounter(&Counters::named_load_inline, 1);
+        deferred->BindExit();
+        cgen_->frame()->Push(&receiver);
+        cgen_->frame()->Push(&value);
+      }
+      break;
+    }
+
+    case KEYED: {
+      // TODO(1241834): Make sure that this it is safe to ignore the
+      // distinction between expressions in a typeof and not in a typeof.
+      Comment cmnt(masm, "[ Load from keyed Property");
+      Variable* var = expression_->AsVariableProxy()->AsVariable();
+      bool is_global = var != NULL;
+      ASSERT(!is_global || var->is_global());
+
+      // Inline array load code if inside of a loop.  We do not know
+      // the receiver map yet, so we initially generate the code with
+      // a check against an invalid map.  In the inline cache code, we
+      // patch the map check if appropriate.
+      if (cgen_->loop_nesting() > 0) {
+        Comment cmnt(masm, "[ Inlined load from keyed Property");
+
+        Result key = cgen_->frame()->Pop();
+        Result receiver = cgen_->frame()->Pop();
+        key.ToRegister();
+        receiver.ToRegister();
+
+        // Use a fresh temporary to load the elements without destroying
+        // the receiver which is needed for the deferred slow case.
+        Result elements = cgen_->allocator()->Allocate();
+        ASSERT(elements.is_valid());
+
+        // Use a fresh temporary for the index and later the loaded
+        // value.
+        Result index = cgen_->allocator()->Allocate();
+        ASSERT(index.is_valid());
+
+        DeferredReferenceGetKeyedValue* deferred =
+            new DeferredReferenceGetKeyedValue(index.reg(),
+                                               receiver.reg(),
+                                               key.reg(),
+                                               is_global);
+
+        // Check that the receiver is not a smi (only needed if this
+        // is not a load from the global context) and that it has the
+        // expected map.
+        if (!is_global) {
+          __ test(receiver.reg(), Immediate(kSmiTagMask));
+          deferred->Branch(zero);
+        }
+
+        // Initially, use an invalid map. The map is patched in the IC
+        // initialization code.
+        __ bind(deferred->patch_site());
+        // Use masm-> here instead of the double underscore macro since extra
+        // coverage code can interfere with the patching.
+        masm->cmp(FieldOperand(receiver.reg(), HeapObject::kMapOffset),
+                  Immediate(Factory::null_value()));
+        deferred->Branch(not_equal);
+
+        // Check that the key is a smi.
+        __ test(key.reg(), Immediate(kSmiTagMask));
+        deferred->Branch(not_zero);
+
+        // Get the elements array from the receiver and check that it
+        // is not a dictionary.
+        __ mov(elements.reg(),
+               FieldOperand(receiver.reg(), JSObject::kElementsOffset));
+        __ cmp(FieldOperand(elements.reg(), HeapObject::kMapOffset),
+               Immediate(Factory::fixed_array_map()));
+        deferred->Branch(not_equal);
+
+        // Shift the key to get the actual index value and check that
+        // it is within bounds.
+        __ mov(index.reg(), key.reg());
+        __ sar(index.reg(), kSmiTagSize);
+        __ cmp(index.reg(),
+               FieldOperand(elements.reg(), FixedArray::kLengthOffset));
+        deferred->Branch(above_equal);
+
+        // Load and check that the result is not the hole.  We could
+        // reuse the index or elements register for the value.
+        //
+        // TODO(206): Consider whether it makes sense to try some
+        // heuristic about which register to reuse.  For example, if
+        // one is eax, the we can reuse that one because the value
+        // coming from the deferred code will be in eax.
+        Result value = index;
+        __ mov(value.reg(), Operand(elements.reg(),
+                                    index.reg(),
+                                    times_4,
+                                    FixedArray::kHeaderSize - kHeapObjectTag));
+        elements.Unuse();
+        index.Unuse();
+        __ cmp(Operand(value.reg()), Immediate(Factory::the_hole_value()));
+        deferred->Branch(equal);
+        __ IncrementCounter(&Counters::keyed_load_inline, 1);
+
+        deferred->BindExit();
+        // Restore the receiver and key to the frame and push the
+        // result on top of it.
+        cgen_->frame()->Push(&receiver);
+        cgen_->frame()->Push(&key);
+        cgen_->frame()->Push(&value);
+
+      } else {
+        Comment cmnt(masm, "[ Load from keyed Property");
+        RelocInfo::Mode mode = is_global
+                               ? RelocInfo::CODE_TARGET_CONTEXT
+                               : RelocInfo::CODE_TARGET;
+        Result answer = cgen_->frame()->CallKeyedLoadIC(mode);
+        // Make sure that we do not have a test instruction after the
+        // call.  A test instruction after the call is used to
+        // indicate that we have generated an inline version of the
+        // keyed load.  The explicit nop instruction is here because
+        // the push that follows might be peep-hole optimized away.
+        __ nop();
+        cgen_->frame()->Push(&answer);
+      }
+      break;
+    }
+
+    default:
+      UNREACHABLE();
+  }
+}
+
+
+void Reference::TakeValue(TypeofState typeof_state) {
+  // For non-constant frame-allocated slots, we invalidate the value in the
+  // slot.  For all others, we fall back on GetValue.
+  ASSERT(!cgen_->in_spilled_code());
+  ASSERT(!is_illegal());
+  if (type_ != SLOT) {
+    GetValue(typeof_state);
+    return;
+  }
+
+  Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
+  ASSERT(slot != NULL);
+  if (slot->type() == Slot::LOOKUP ||
+      slot->type() == Slot::CONTEXT ||
+      slot->var()->mode() == Variable::CONST ||
+      slot->is_arguments()) {
+    GetValue(typeof_state);
+    return;
+  }
+
+  // Only non-constant, frame-allocated parameters and locals can
+  // reach here. Be careful not to use the optimizations for arguments
+  // object access since it may not have been initialized yet.
+  ASSERT(!slot->is_arguments());
+  if (slot->type() == Slot::PARAMETER) {
+    cgen_->frame()->TakeParameterAt(slot->index());
+  } else {
+    ASSERT(slot->type() == Slot::LOCAL);
+    cgen_->frame()->TakeLocalAt(slot->index());
+  }
+}
+
+
+void Reference::SetValue(InitState init_state) {
+  ASSERT(cgen_->HasValidEntryRegisters());
+  ASSERT(!is_illegal());
+  MacroAssembler* masm = cgen_->masm();
+  switch (type_) {
+    case SLOT: {
+      Comment cmnt(masm, "[ Store to Slot");
+      Slot* slot = expression_->AsVariableProxy()->AsVariable()->slot();
+      ASSERT(slot != NULL);
+      cgen_->StoreToSlot(slot, init_state);
+      break;
+    }
+
+    case NAMED: {
+      Comment cmnt(masm, "[ Store to named Property");
+      cgen_->frame()->Push(GetName());
+      Result answer = cgen_->frame()->CallStoreIC();
+      cgen_->frame()->Push(&answer);
+      break;
+    }
+
+    case KEYED: {
+      Comment cmnt(masm, "[ Store to keyed Property");
+
+      // Generate inlined version of the keyed store if the code is in
+      // a loop and the key is likely to be a smi.
+      Property* property = expression()->AsProperty();
+      ASSERT(property != NULL);
+      SmiAnalysis* key_smi_analysis = property->key()->type();
+
+      if (cgen_->loop_nesting() > 0 && key_smi_analysis->IsLikelySmi()) {
+        Comment cmnt(masm, "[ Inlined store to keyed Property");
+
+        // Get the receiver, key and value into registers.
+        Result value = cgen_->frame()->Pop();
+        Result key = cgen_->frame()->Pop();
+        Result receiver = cgen_->frame()->Pop();
+
+        Result tmp = cgen_->allocator_->Allocate();
+        ASSERT(tmp.is_valid());
+
+        // Determine whether the value is a constant before putting it
+        // in a register.
+        bool value_is_constant = value.is_constant();
+
+        // Make sure that value, key and receiver are in registers.
+        value.ToRegister();
+        key.ToRegister();
+        receiver.ToRegister();
+
+        DeferredReferenceSetKeyedValue* deferred =
+            new DeferredReferenceSetKeyedValue(value.reg(),
+                                               key.reg(),
+                                               receiver.reg());
+
+        // Check that the value is a smi if it is not a constant.  We
+        // can skip the write barrier for smis and constants.
+        if (!value_is_constant) {
+          __ test(value.reg(), Immediate(kSmiTagMask));
+          deferred->Branch(not_zero);
+        }
+
+        // Check that the key is a non-negative smi.
+        __ test(key.reg(), Immediate(kSmiTagMask | 0x80000000));
+        deferred->Branch(not_zero);
+
+        // Check that the receiver is not a smi.
+        __ test(receiver.reg(), Immediate(kSmiTagMask));
+        deferred->Branch(zero);
+
+        // Check that the receiver is a JSArray.
+        __ mov(tmp.reg(),
+               FieldOperand(receiver.reg(), HeapObject::kMapOffset));
+        __ movzx_b(tmp.reg(),
+                   FieldOperand(tmp.reg(), Map::kInstanceTypeOffset));
+        __ cmp(tmp.reg(), JS_ARRAY_TYPE);
+        deferred->Branch(not_equal);
+
+        // Check that the key is within bounds.  Both the key and the
+        // length of the JSArray are smis.
+        __ cmp(key.reg(),
+               FieldOperand(receiver.reg(), JSArray::kLengthOffset));
+        deferred->Branch(greater_equal);
+
+        // Get the elements array from the receiver and check that it
+        // is not a dictionary.
+        __ mov(tmp.reg(),
+               FieldOperand(receiver.reg(), JSObject::kElementsOffset));
+        // Bind the deferred code patch site to be able to locate the
+        // fixed array map comparison.  When debugging, we patch this
+        // comparison to always fail so that we will hit the IC call
+        // in the deferred code which will allow the debugger to
+        // break for fast case stores.
+        __ bind(deferred->patch_site());
+        __ cmp(FieldOperand(tmp.reg(), HeapObject::kMapOffset),
+               Immediate(Factory::fixed_array_map()));
+        deferred->Branch(not_equal);
+
+        // Store the value.
+        __ mov(Operand(tmp.reg(),
+                       key.reg(),
+                       times_2,
+                       FixedArray::kHeaderSize - kHeapObjectTag),
+               value.reg());
+        __ IncrementCounter(&Counters::keyed_store_inline, 1);
+
+        deferred->BindExit();
+
+        cgen_->frame()->Push(&receiver);
+        cgen_->frame()->Push(&key);
+        cgen_->frame()->Push(&value);
+      } else {
+        Result answer = cgen_->frame()->CallKeyedStoreIC();
+        // Make sure that we do not have a test instruction after the
+        // call.  A test instruction after the call is used to
+        // indicate that we have generated an inline version of the
+        // keyed store.
+        __ nop();
+        cgen_->frame()->Push(&answer);
+      }
+      break;
+    }
+
+    default:
+      UNREACHABLE();
+  }
+}
+
+
+// NOTE: The stub does not handle the inlined cases (Smis, Booleans, undefined).
+void ToBooleanStub::Generate(MacroAssembler* masm) {
+  Label false_result, true_result, not_string;
+  __ mov(eax, Operand(esp, 1 * kPointerSize));
+
+  // 'null' => false.
+  __ cmp(eax, Factory::null_value());
+  __ j(equal, &false_result);
+
+  // Get the map and type of the heap object.
+  __ mov(edx, FieldOperand(eax, HeapObject::kMapOffset));
+  __ movzx_b(ecx, FieldOperand(edx, Map::kInstanceTypeOffset));
+
+  // Undetectable => false.
+  __ movzx_b(ebx, FieldOperand(edx, Map::kBitFieldOffset));
+  __ and_(ebx, 1 << Map::kIsUndetectable);
+  __ j(not_zero, &false_result);
+
+  // JavaScript object => true.
+  __ cmp(ecx, FIRST_JS_OBJECT_TYPE);
+  __ j(above_equal, &true_result);
+
+  // String value => false iff empty.
+  __ cmp(ecx, FIRST_NONSTRING_TYPE);
+  __ j(above_equal, &not_string);
+  __ and_(ecx, kStringSizeMask);
+  __ cmp(ecx, kShortStringTag);
+  __ j(not_equal, &true_result);  // Empty string is always short.
+  __ mov(edx, FieldOperand(eax, String::kLengthOffset));
+  __ shr(edx, String::kShortLengthShift);
+  __ j(zero, &false_result);
+  __ jmp(&true_result);
+
+  __ bind(&not_string);
+  // HeapNumber => false iff +0, -0, or NaN.
+  __ cmp(edx, Factory::heap_number_map());
+  __ j(not_equal, &true_result);
+  __ fldz();
+  __ fld_d(FieldOperand(eax, HeapNumber::kValueOffset));
+  __ fucompp();
+  __ push(eax);
+  __ fnstsw_ax();
+  __ sahf();
+  __ pop(eax);
+  __ j(zero, &false_result);
+  // Fall through to |true_result|.
+
+  // Return 1/0 for true/false in eax.
+  __ bind(&true_result);
+  __ mov(eax, 1);
+  __ ret(1 * kPointerSize);
+  __ bind(&false_result);
+  __ mov(eax, 0);
+  __ ret(1 * kPointerSize);
+}
+
+
+void GenericBinaryOpStub::GenerateSmiCode(MacroAssembler* masm, Label* slow) {
+  // Perform fast-case smi code for the operation (eax <op> ebx) and
+  // leave result in register eax.
+
+  // Prepare the smi check of both operands by or'ing them together
+  // before checking against the smi mask.
+  __ mov(ecx, Operand(ebx));
+  __ or_(ecx, Operand(eax));
+
+  switch (op_) {
+    case Token::ADD:
+      __ add(eax, Operand(ebx));  // add optimistically
+      __ j(overflow, slow, not_taken);
+      break;
+
+    case Token::SUB:
+      __ sub(eax, Operand(ebx));  // subtract optimistically
+      __ j(overflow, slow, not_taken);
+      break;
+
+    case Token::DIV:
+    case Token::MOD:
+      // Sign extend eax into edx:eax.
+      __ cdq();
+      // Check for 0 divisor.
+      __ test(ebx, Operand(ebx));
+      __ j(zero, slow, not_taken);
+      break;
+
+    default:
+      // Fall-through to smi check.
+      break;
+  }
+
+  // Perform the actual smi check.
+  ASSERT(kSmiTag == 0);  // adjust zero check if not the case
+  __ test(ecx, Immediate(kSmiTagMask));
+  __ j(not_zero, slow, not_taken);
+
+  switch (op_) {
+    case Token::ADD:
+    case Token::SUB:
+      // Do nothing here.
+      break;
+
+    case Token::MUL:
+      // If the smi tag is 0 we can just leave the tag on one operand.
+      ASSERT(kSmiTag == 0);  // adjust code below if not the case
+      // Remove tag from one of the operands (but keep sign).
+      __ sar(eax, kSmiTagSize);
+      // Do multiplication.
+      __ imul(eax, Operand(ebx));  // multiplication of smis; result in eax
+      // Go slow on overflows.
+      __ j(overflow, slow, not_taken);
+      // Check for negative zero result.
+      __ NegativeZeroTest(eax, ecx, slow);  // use ecx = x | y
+      break;
+
+    case Token::DIV:
+      // Divide edx:eax by ebx.
+      __ idiv(ebx);
+      // Check for the corner case of dividing the most negative smi
+      // by -1. We cannot use the overflow flag, since it is not set
+      // by idiv instruction.
+      ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
+      __ cmp(eax, 0x40000000);
+      __ j(equal, slow);
+      // Check for negative zero result.
+      __ NegativeZeroTest(eax, ecx, slow);  // use ecx = x | y
+      // Check that the remainder is zero.
+      __ test(edx, Operand(edx));
+      __ j(not_zero, slow);
+      // Tag the result and store it in register eax.
+      ASSERT(kSmiTagSize == times_2);  // adjust code if not the case
+      __ lea(eax, Operand(eax, eax, times_1, kSmiTag));
+      break;
+
+    case Token::MOD:
+      // Divide edx:eax by ebx.
+      __ idiv(ebx);
+      // Check for negative zero result.
+      __ NegativeZeroTest(edx, ecx, slow);  // use ecx = x | y
+      // Move remainder to register eax.
+      __ mov(eax, Operand(edx));
+      break;
+
+    case Token::BIT_OR:
+      __ or_(eax, Operand(ebx));
+      break;
+
+    case Token::BIT_AND:
+      __ and_(eax, Operand(ebx));
+      break;
+
+    case Token::BIT_XOR:
+      __ xor_(eax, Operand(ebx));
+      break;
+
+    case Token::SHL:
+    case Token::SHR:
+    case Token::SAR:
+      // Move the second operand into register ecx.
+      __ mov(ecx, Operand(ebx));
+      // Remove tags from operands (but keep sign).
+      __ sar(eax, kSmiTagSize);
+      __ sar(ecx, kSmiTagSize);
+      // Perform the operation.
+      switch (op_) {
+        case Token::SAR:
+          __ sar(eax);
+          // No checks of result necessary
+          break;
+        case Token::SHR:
+          __ shr(eax);
+          // Check that the *unsigned* result fits in a smi.
+          // Neither of the two high-order bits can be set:
+          // - 0x80000000: high bit would be lost when smi tagging.
+          // - 0x40000000: this number would convert to negative when
+          // Smi tagging these two cases can only happen with shifts
+          // by 0 or 1 when handed a valid smi.
+          __ test(eax, Immediate(0xc0000000));
+          __ j(not_zero, slow, not_taken);
+          break;
+        case Token::SHL:
+          __ shl(eax);
+          // Check that the *signed* result fits in a smi.
+          __ cmp(eax, 0xc0000000);
+          __ j(sign, slow, not_taken);
+          break;
+        default:
+          UNREACHABLE();
+      }
+      // Tag the result and store it in register eax.
+      ASSERT(kSmiTagSize == times_2);  // adjust code if not the case
+      __ lea(eax, Operand(eax, eax, times_1, kSmiTag));
+      break;
+
+    default:
+      UNREACHABLE();
+      break;
+  }
+}
+
+
+void GenericBinaryOpStub::Generate(MacroAssembler* masm) {
+  Label call_runtime;
+
+  if (flags_ == SMI_CODE_IN_STUB) {
+    // The fast case smi code wasn't inlined in the stub caller
+    // code. Generate it here to speed up common operations.
+    Label slow;
+    __ mov(ebx, Operand(esp, 1 * kPointerSize));  // get y
+    __ mov(eax, Operand(esp, 2 * kPointerSize));  // get x
+    GenerateSmiCode(masm, &slow);
+    __ ret(2 * kPointerSize);  // remove both operands
+
+    // Too bad. The fast case smi code didn't succeed.
+    __ bind(&slow);
+  }
+
+  // Setup registers.
+  __ mov(eax, Operand(esp, 1 * kPointerSize));  // get y
+  __ mov(edx, Operand(esp, 2 * kPointerSize));  // get x
+
+  // Floating point case.
+  switch (op_) {
+    case Token::ADD:
+    case Token::SUB:
+    case Token::MUL:
+    case Token::DIV: {
+      // eax: y
+      // edx: x
+
+      if (CpuFeatures::IsSupported(CpuFeatures::SSE2)) {
+        CpuFeatures::Scope use_sse2(CpuFeatures::SSE2);
+        FloatingPointHelper::LoadSse2Operands(masm, &call_runtime);
+
+        switch (op_) {
+          case Token::ADD: __ addsd(xmm0, xmm1); break;
+          case Token::SUB: __ subsd(xmm0, xmm1); break;
+          case Token::MUL: __ mulsd(xmm0, xmm1); break;
+          case Token::DIV: __ divsd(xmm0, xmm1); break;
+          default: UNREACHABLE();
+        }
+        // Allocate a heap number, if needed.
+        Label skip_allocation;
+        switch (mode_) {
+          case OVERWRITE_LEFT:
+            __ mov(eax, Operand(edx));
+            // Fall through!
+          case OVERWRITE_RIGHT:
+            // If the argument in eax is already an object, we skip the
+            // allocation of a heap number.
+            __ test(eax, Immediate(kSmiTagMask));
+            __ j(not_zero, &skip_allocation, not_taken);
+            // Fall through!
+          case NO_OVERWRITE:
+            FloatingPointHelper::AllocateHeapNumber(masm,
+                                                    &call_runtime,
+                                                    ecx,
+                                                    edx,
+                                                    eax);
+            __ bind(&skip_allocation);
+            break;
+          default: UNREACHABLE();
+        }
+        __ movdbl(FieldOperand(eax, HeapNumber::kValueOffset), xmm0);
+        __ ret(2 * kPointerSize);
+
+      } else {  // SSE2 not available, use FPU.
+        FloatingPointHelper::CheckFloatOperands(masm, &call_runtime, ebx);
+        // Allocate a heap number, if needed.
+        Label skip_allocation;
+        switch (mode_) {
+          case OVERWRITE_LEFT:
+            __ mov(eax, Operand(edx));
+            // Fall through!
+          case OVERWRITE_RIGHT:
+            // If the argument in eax is already an object, we skip the
+            // allocation of a heap number.
+            __ test(eax, Immediate(kSmiTagMask));
+            __ j(not_zero, &skip_allocation, not_taken);
+            // Fall through!
+          case NO_OVERWRITE:
+            FloatingPointHelper::AllocateHeapNumber(masm,
+                                                    &call_runtime,
+                                                    ecx,
+                                                    edx,
+                                                    eax);
+            __ bind(&skip_allocation);
+            break;
+          default: UNREACHABLE();
+        }
+        FloatingPointHelper::LoadFloatOperands(masm, ecx);
+
+        switch (op_) {
+          case Token::ADD: __ faddp(1); break;
+          case Token::SUB: __ fsubp(1); break;
+          case Token::MUL: __ fmulp(1); break;
+          case Token::DIV: __ fdivp(1); break;
+          default: UNREACHABLE();
+        }
+        __ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
+        __ ret(2 * kPointerSize);
+      }
+    }
+    case Token::MOD: {
+      // For MOD we go directly to runtime in the non-smi case.
+      break;
+    }
+    case Token::BIT_OR:
+    case Token::BIT_AND:
+    case Token::BIT_XOR:
+    case Token::SAR:
+    case Token::SHL:
+    case Token::SHR: {
+      FloatingPointHelper::CheckFloatOperands(masm, &call_runtime, ebx);
+      FloatingPointHelper::LoadFloatOperands(masm, ecx);
+
+      Label skip_allocation, non_smi_result, operand_conversion_failure;
+
+      // Reserve space for converted numbers.
+      __ sub(Operand(esp), Immediate(2 * kPointerSize));
+
+      if (use_sse3_) {
+        // Truncate the operands to 32-bit integers and check for
+        // exceptions in doing so.
+        CpuFeatures::Scope scope(CpuFeatures::SSE3);
+        __ fisttp_s(Operand(esp, 0 * kPointerSize));
+        __ fisttp_s(Operand(esp, 1 * kPointerSize));
+        __ fnstsw_ax();
+        __ test(eax, Immediate(1));
+        __ j(not_zero, &operand_conversion_failure);
+      } else {
+        // Check if right operand is int32.
+        __ fist_s(Operand(esp, 0 * kPointerSize));
+        __ fild_s(Operand(esp, 0 * kPointerSize));
+        __ fucompp();
+        __ fnstsw_ax();
+        __ sahf();
+        __ j(not_zero, &operand_conversion_failure);
+        __ j(parity_even, &operand_conversion_failure);
+
+        // Check if left operand is int32.
+        __ fist_s(Operand(esp, 1 * kPointerSize));
+        __ fild_s(Operand(esp, 1 * kPointerSize));
+        __ fucompp();
+        __ fnstsw_ax();
+        __ sahf();
+        __ j(not_zero, &operand_conversion_failure);
+        __ j(parity_even, &operand_conversion_failure);
+      }
+
+      // Get int32 operands and perform bitop.
+      __ pop(ecx);
+      __ pop(eax);
+      switch (op_) {
+        case Token::BIT_OR:  __ or_(eax, Operand(ecx)); break;
+        case Token::BIT_AND: __ and_(eax, Operand(ecx)); break;
+        case Token::BIT_XOR: __ xor_(eax, Operand(ecx)); break;
+        case Token::SAR: __ sar(eax); break;
+        case Token::SHL: __ shl(eax); break;
+        case Token::SHR: __ shr(eax); break;
+        default: UNREACHABLE();
+      }
+      if (op_ == Token::SHR) {
+        // Check if result is non-negative and fits in a smi.
+        __ test(eax, Immediate(0xc0000000));
+        __ j(not_zero, &non_smi_result);
+      } else {
+        // Check if result fits in a smi.
+        __ cmp(eax, 0xc0000000);
+        __ j(negative, &non_smi_result);
+      }
+      // Tag smi result and return.
+      ASSERT(kSmiTagSize == times_2);  // adjust code if not the case
+      __ lea(eax, Operand(eax, eax, times_1, kSmiTag));
+      __ ret(2 * kPointerSize);
+
+      // All ops except SHR return a signed int32 that we load in a HeapNumber.
+      if (op_ != Token::SHR) {
+        __ bind(&non_smi_result);
+        // Allocate a heap number if needed.
+        __ mov(ebx, Operand(eax));  // ebx: result
+        switch (mode_) {
+          case OVERWRITE_LEFT:
+          case OVERWRITE_RIGHT:
+            // If the operand was an object, we skip the
+            // allocation of a heap number.
+            __ mov(eax, Operand(esp, mode_ == OVERWRITE_RIGHT ?
+                                1 * kPointerSize : 2 * kPointerSize));
+            __ test(eax, Immediate(kSmiTagMask));
+            __ j(not_zero, &skip_allocation, not_taken);
+            // Fall through!
+          case NO_OVERWRITE:
+            FloatingPointHelper::AllocateHeapNumber(masm, &call_runtime,
+                                                    ecx, edx, eax);
+            __ bind(&skip_allocation);
+            break;
+          default: UNREACHABLE();
+        }
+        // Store the result in the HeapNumber and return.
+        __ mov(Operand(esp, 1 * kPointerSize), ebx);
+        __ fild_s(Operand(esp, 1 * kPointerSize));
+        __ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
+        __ ret(2 * kPointerSize);
+      }
+
+      // Clear the FPU exception flag and reset the stack before calling
+      // the runtime system.
+      __ bind(&operand_conversion_failure);
+      __ add(Operand(esp), Immediate(2 * kPointerSize));
+      if (use_sse3_) {
+        // If we've used the SSE3 instructions for truncating the
+        // floating point values to integers and it failed, we have a
+        // pending #IA exception. Clear it.
+        __ fnclex();
+      } else {
+        // The non-SSE3 variant does early bailout if the right
+        // operand isn't a 32-bit integer, so we may have a single
+        // value on the FPU stack we need to get rid of.
+        __ ffree(0);
+      }
+
+      // SHR should return uint32 - go to runtime for non-smi/negative result.
+      if (op_ == Token::SHR) {
+        __ bind(&non_smi_result);
+      }
+      __ mov(eax, Operand(esp, 1 * kPointerSize));
+      __ mov(edx, Operand(esp, 2 * kPointerSize));
+      break;
+    }
+    default: UNREACHABLE(); break;
+  }
+
+  // If all else fails, use the runtime system to get the correct
+  // result.
+  __ bind(&call_runtime);
+  switch (op_) {
+    case Token::ADD: {
+      // Test for string arguments before calling runtime.
+      Label not_strings, both_strings, not_string1, string1;
+      Result answer;
+      __ mov(eax, Operand(esp, 2 * kPointerSize));  // First argument.
+      __ mov(edx, Operand(esp, 1 * kPointerSize));  // Second argument.
+      __ test(eax, Immediate(kSmiTagMask));
+      __ j(zero, &not_string1);
+      __ CmpObjectType(eax, FIRST_NONSTRING_TYPE, eax);
+      __ j(above_equal, &not_string1);
+
+      // First argument is a a string, test second.
+      __ test(edx, Immediate(kSmiTagMask));
+      __ j(zero, &string1);
+      __ CmpObjectType(edx, FIRST_NONSTRING_TYPE, edx);
+      __ j(above_equal, &string1);
+
+      // First and second argument are strings.
+      __ TailCallRuntime(ExternalReference(Runtime::kStringAdd), 2, 1);
+
+      // Only first argument is a string.
+      __ bind(&string1);
+      __ InvokeBuiltin(Builtins::STRING_ADD_LEFT, JUMP_FUNCTION);
+
+      // First argument was not a string, test second.
+      __ bind(&not_string1);
+      __ test(edx, Immediate(kSmiTagMask));
+      __ j(zero, &not_strings);
+      __ CmpObjectType(edx, FIRST_NONSTRING_TYPE, edx);
+      __ j(above_equal, &not_strings);
+
+      // Only second argument is a string.
+      __ InvokeBuiltin(Builtins::STRING_ADD_RIGHT, JUMP_FUNCTION);
+
+      __ bind(&not_strings);
+      // Neither argument is a string.
+      __ InvokeBuiltin(Builtins::ADD, JUMP_FUNCTION);
+      break;
+    }
+    case Token::SUB:
+      __ InvokeBuiltin(Builtins::SUB, JUMP_FUNCTION);
+      break;
+    case Token::MUL:
+      __ InvokeBuiltin(Builtins::MUL, JUMP_FUNCTION);
+        break;
+    case Token::DIV:
+      __ InvokeBuiltin(Builtins::DIV, JUMP_FUNCTION);
+      break;
+    case Token::MOD:
+      __ InvokeBuiltin(Builtins::MOD, JUMP_FUNCTION);
+      break;
+    case Token::BIT_OR:
+      __ InvokeBuiltin(Builtins::BIT_OR, JUMP_FUNCTION);
+      break;
+    case Token::BIT_AND:
+      __ InvokeBuiltin(Builtins::BIT_AND, JUMP_FUNCTION);
+      break;
+    case Token::BIT_XOR:
+      __ InvokeBuiltin(Builtins::BIT_XOR, JUMP_FUNCTION);
+      break;
+    case Token::SAR:
+      __ InvokeBuiltin(Builtins::SAR, JUMP_FUNCTION);
+      break;
+    case Token::SHL:
+      __ InvokeBuiltin(Builtins::SHL, JUMP_FUNCTION);
+      break;
+    case Token::SHR:
+      __ InvokeBuiltin(Builtins::SHR, JUMP_FUNCTION);
+      break;
+    default:
+      UNREACHABLE();
+  }
+}
+
+
+void FloatingPointHelper::AllocateHeapNumber(MacroAssembler* masm,
+                                             Label* need_gc,
+                                             Register scratch1,
+                                             Register scratch2,
+                                             Register result) {
+  // Allocate heap number in new space.
+  __ AllocateInNewSpace(HeapNumber::kSize,
+                        result,
+                        scratch1,
+                        scratch2,
+                        need_gc,
+                        TAG_OBJECT);
+
+  // Set the map.
+  __ mov(FieldOperand(result, HeapObject::kMapOffset),
+         Immediate(Factory::heap_number_map()));
+}
+
+
+void FloatingPointHelper::LoadFloatOperand(MacroAssembler* masm,
+                                           Register number) {
+  Label load_smi, done;
+
+  __ test(number, Immediate(kSmiTagMask));
+  __ j(zero, &load_smi, not_taken);
+  __ fld_d(FieldOperand(number, HeapNumber::kValueOffset));
+  __ jmp(&done);
+
+  __ bind(&load_smi);
+  __ sar(number, kSmiTagSize);
+  __ push(number);
+  __ fild_s(Operand(esp, 0));
+  __ pop(number);
+
+  __ bind(&done);
+}
+
+
+void FloatingPointHelper::LoadSse2Operands(MacroAssembler* masm,
+                                           Label* not_numbers) {
+  Label load_smi_edx, load_eax, load_smi_eax, load_float_eax, done;
+  // Load operand in edx into xmm0, or branch to not_numbers.
+  __ test(edx, Immediate(kSmiTagMask));
+  __ j(zero, &load_smi_edx, not_taken);  // Argument in edx is a smi.
+  __ cmp(FieldOperand(edx, HeapObject::kMapOffset), Factory::heap_number_map());
+  __ j(not_equal, not_numbers);  // Argument in edx is not a number.
+  __ movdbl(xmm0, FieldOperand(edx, HeapNumber::kValueOffset));
+  __ bind(&load_eax);
+  // Load operand in eax into xmm1, or branch to not_numbers.
+  __ test(eax, Immediate(kSmiTagMask));
+  __ j(zero, &load_smi_eax, not_taken);  // Argument in eax is a smi.
+  __ cmp(FieldOperand(eax, HeapObject::kMapOffset), Factory::heap_number_map());
+  __ j(equal, &load_float_eax);
+  __ jmp(not_numbers);  // Argument in eax is not a number.
+  __ bind(&load_smi_edx);
+  __ sar(edx, 1);  // Untag smi before converting to float.
+  __ cvtsi2sd(xmm0, Operand(edx));
+  __ shl(edx, 1);  // Retag smi for heap number overwriting test.
+  __ jmp(&load_eax);
+  __ bind(&load_smi_eax);
+  __ sar(eax, 1);  // Untag smi before converting to float.
+  __ cvtsi2sd(xmm1, Operand(eax));
+  __ shl(eax, 1);  // Retag smi for heap number overwriting test.
+  __ jmp(&done);
+  __ bind(&load_float_eax);
+  __ movdbl(xmm1, FieldOperand(eax, HeapNumber::kValueOffset));
+  __ bind(&done);
+}
+
+
+void FloatingPointHelper::LoadFloatOperands(MacroAssembler* masm,
+                                            Register scratch) {
+  Label load_smi_1, load_smi_2, done_load_1, done;
+  __ mov(scratch, Operand(esp, 2 * kPointerSize));
+  __ test(scratch, Immediate(kSmiTagMask));
+  __ j(zero, &load_smi_1, not_taken);
+  __ fld_d(FieldOperand(scratch, HeapNumber::kValueOffset));
+  __ bind(&done_load_1);
+
+  __ mov(scratch, Operand(esp, 1 * kPointerSize));
+  __ test(scratch, Immediate(kSmiTagMask));
+  __ j(zero, &load_smi_2, not_taken);
+  __ fld_d(FieldOperand(scratch, HeapNumber::kValueOffset));
+  __ jmp(&done);
+
+  __ bind(&load_smi_1);
+  __ sar(scratch, kSmiTagSize);
+  __ push(scratch);
+  __ fild_s(Operand(esp, 0));
+  __ pop(scratch);
+  __ jmp(&done_load_1);
+
+  __ bind(&load_smi_2);
+  __ sar(scratch, kSmiTagSize);
+  __ push(scratch);
+  __ fild_s(Operand(esp, 0));
+  __ pop(scratch);
+
+  __ bind(&done);
+}
+
+
+void FloatingPointHelper::CheckFloatOperands(MacroAssembler* masm,
+                                             Label* non_float,
+                                             Register scratch) {
+  Label test_other, done;
+  // Test if both operands are floats or smi -> scratch=k_is_float;
+  // Otherwise scratch = k_not_float.
+  __ test(edx, Immediate(kSmiTagMask));
+  __ j(zero, &test_other, not_taken);  // argument in edx is OK
+  __ mov(scratch, FieldOperand(edx, HeapObject::kMapOffset));
+  __ cmp(scratch, Factory::heap_number_map());
+  __ j(not_equal, non_float);  // argument in edx is not a number -> NaN
+
+  __ bind(&test_other);
+  __ test(eax, Immediate(kSmiTagMask));
+  __ j(zero, &done);  // argument in eax is OK
+  __ mov(scratch, FieldOperand(eax, HeapObject::kMapOffset));
+  __ cmp(scratch, Factory::heap_number_map());
+  __ j(not_equal, non_float);  // argument in eax is not a number -> NaN
+
+  // Fall-through: Both operands are numbers.
+  __ bind(&done);
+}
+
+
+void UnarySubStub::Generate(MacroAssembler* masm) {
+  Label undo;
+  Label slow;
+  Label done;
+  Label try_float;
+
+  // Check whether the value is a smi.
+  __ test(eax, Immediate(kSmiTagMask));
+  __ j(not_zero, &try_float, not_taken);
+
+  // Enter runtime system if the value of the expression is zero
+  // to make sure that we switch between 0 and -0.
+  __ test(eax, Operand(eax));
+  __ j(zero, &slow, not_taken);
+
+  // The value of the expression is a smi that is not zero.  Try
+  // optimistic subtraction '0 - value'.
+  __ mov(edx, Operand(eax));
+  __ Set(eax, Immediate(0));
+  __ sub(eax, Operand(edx));
+  __ j(overflow, &undo, not_taken);
+
+  // If result is a smi we are done.
+  __ test(eax, Immediate(kSmiTagMask));
+  __ j(zero, &done, taken);
+
+  // Restore eax and enter runtime system.
+  __ bind(&undo);
+  __ mov(eax, Operand(edx));
+
+  // Enter runtime system.
+  __ bind(&slow);
+  __ pop(ecx);  // pop return address
+  __ push(eax);
+  __ push(ecx);  // push return address
+  __ InvokeBuiltin(Builtins::UNARY_MINUS, JUMP_FUNCTION);
+
+  // Try floating point case.
+  __ bind(&try_float);
+  __ mov(edx, FieldOperand(eax, HeapObject::kMapOffset));
+  __ cmp(edx, Factory::heap_number_map());
+  __ j(not_equal, &slow);
+  if (overwrite_) {
+    __ mov(edx, FieldOperand(eax, HeapNumber::kExponentOffset));
+    __ xor_(edx, HeapNumber::kSignMask);  // Flip sign.
+    __ mov(FieldOperand(eax, HeapNumber::kExponentOffset), edx);
+  } else {
+    __ mov(edx, Operand(eax));
+    // edx: operand
+    FloatingPointHelper::AllocateHeapNumber(masm, &undo, ebx, ecx, eax);
+    // eax: allocated 'empty' number
+    __ mov(ecx, FieldOperand(edx, HeapNumber::kExponentOffset));
+    __ xor_(ecx, HeapNumber::kSignMask);  // Flip sign.
+    __ mov(FieldOperand(eax, HeapNumber::kExponentOffset), ecx);
+    __ mov(ecx, FieldOperand(edx, HeapNumber::kMantissaOffset));
+    __ mov(FieldOperand(eax, HeapNumber::kMantissaOffset), ecx);
+  }
+
+  __ bind(&done);
+
+  __ StubReturn(1);
+}
+
+
+void ArgumentsAccessStub::GenerateReadLength(MacroAssembler* masm) {
+  // Check if the calling frame is an arguments adaptor frame.
+  Label adaptor;
+  __ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
+  __ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
+  __ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ j(equal, &adaptor);
+
+  // Nothing to do: The formal number of parameters has already been
+  // passed in register eax by calling function. Just return it.
+  __ ret(0);
+
+  // Arguments adaptor case: Read the arguments length from the
+  // adaptor frame and return it.
+  __ bind(&adaptor);
+  __ mov(eax, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
+  __ ret(0);
+}
+
+
+void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* masm) {
+  // The key is in edx and the parameter count is in eax.
+
+  // The displacement is used for skipping the frame pointer on the
+  // stack. It is the offset of the last parameter (if any) relative
+  // to the frame pointer.
+  static const int kDisplacement = 1 * kPointerSize;
+
+  // Check that the key is a smi.
+  Label slow;
+  __ test(edx, Immediate(kSmiTagMask));
+  __ j(not_zero, &slow, not_taken);
+
+  // Check if the calling frame is an arguments adaptor frame.
+  Label adaptor;
+  __ mov(ebx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
+  __ mov(ecx, Operand(ebx, StandardFrameConstants::kContextOffset));
+  __ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ j(equal, &adaptor);
+
+  // Check index against formal parameters count limit passed in
+  // through register eax. Use unsigned comparison to get negative
+  // check for free.
+  __ cmp(edx, Operand(eax));
+  __ j(above_equal, &slow, not_taken);
+
+  // Read the argument from the stack and return it.
+  ASSERT(kSmiTagSize == 1 && kSmiTag == 0);  // shifting code depends on this
+  __ lea(ebx, Operand(ebp, eax, times_2, 0));
+  __ neg(edx);
+  __ mov(eax, Operand(ebx, edx, times_2, kDisplacement));
+  __ ret(0);
+
+  // Arguments adaptor case: Check index against actual arguments
+  // limit found in the arguments adaptor frame. Use unsigned
+  // comparison to get negative check for free.
+  __ bind(&adaptor);
+  __ mov(ecx, Operand(ebx, ArgumentsAdaptorFrameConstants::kLengthOffset));
+  __ cmp(edx, Operand(ecx));
+  __ j(above_equal, &slow, not_taken);
+
+  // Read the argument from the stack and return it.
+  ASSERT(kSmiTagSize == 1 && kSmiTag == 0);  // shifting code depends on this
+  __ lea(ebx, Operand(ebx, ecx, times_2, 0));
+  __ neg(edx);
+  __ mov(eax, Operand(ebx, edx, times_2, kDisplacement));
+  __ ret(0);
+
+  // Slow-case: Handle non-smi or out-of-bounds access to arguments
+  // by calling the runtime system.
+  __ bind(&slow);
+  __ pop(ebx);  // Return address.
+  __ push(edx);
+  __ push(ebx);
+  __ TailCallRuntime(ExternalReference(Runtime::kGetArgumentsProperty), 1, 1);
+}
+
+
+void ArgumentsAccessStub::GenerateNewObject(MacroAssembler* masm) {
+  // The displacement is used for skipping the return address and the
+  // frame pointer on the stack. It is the offset of the last
+  // parameter (if any) relative to the frame pointer.
+  static const int kDisplacement = 2 * kPointerSize;
+
+  // Check if the calling frame is an arguments adaptor frame.
+  Label runtime;
+  __ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
+  __ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
+  __ cmp(Operand(ecx), Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ j(not_equal, &runtime);
+
+  // Patch the arguments.length and the parameters pointer.
+  __ mov(ecx, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
+  __ mov(Operand(esp, 1 * kPointerSize), ecx);
+  __ lea(edx, Operand(edx, ecx, times_2, kDisplacement));
+  __ mov(Operand(esp, 2 * kPointerSize), edx);
+
+  // Do the runtime call to allocate the arguments object.
+  __ bind(&runtime);
+  __ TailCallRuntime(ExternalReference(Runtime::kNewArgumentsFast), 3, 1);
+}
+
+
+void CompareStub::Generate(MacroAssembler* masm) {
+  Label call_builtin, done;
+
+  // NOTICE! This code is only reached after a smi-fast-case check, so
+  // it is certain that at least one operand isn't a smi.
+
+  if (cc_ == equal) {  // Both strict and non-strict.
+    Label slow;  // Fallthrough label.
+    // Equality is almost reflexive (everything but NaN), so start by testing
+    // for "identity and not NaN".
+    {
+      Label not_identical;
+      __ cmp(eax, Operand(edx));
+      __ j(not_equal, &not_identical);
+      // Test for NaN. Sadly, we can't just compare to Factory::nan_value(),
+      // so we do the second best thing - test it ourselves.
+
+      Label return_equal;
+      Label heap_number;
+      // If it's not a heap number, then return equal.
+      __ cmp(FieldOperand(edx, HeapObject::kMapOffset),
+             Immediate(Factory::heap_number_map()));
+      __ j(equal, &heap_number);
+      __ bind(&return_equal);
+      __ Set(eax, Immediate(0));
+      __ ret(0);
+
+      __ bind(&heap_number);
+      // It is a heap number, so return non-equal if it's NaN and equal if it's
+      // not NaN.
+      // The representation of NaN values has all exponent bits (52..62) set,
+      // and not all mantissa bits (0..51) clear.
+      // Read top bits of double representation (second word of value).
+      __ mov(eax, FieldOperand(edx, HeapNumber::kExponentOffset));
+      // Test that exponent bits are all set.
+      __ not_(eax);
+      __ test(eax, Immediate(0x7ff00000));
+      __ j(not_zero, &return_equal);
+      __ not_(eax);
+
+      // Shift out flag and all exponent bits, retaining only mantissa.
+      __ shl(eax, 12);
+      // Or with all low-bits of mantissa.
+      __ or_(eax, FieldOperand(edx, HeapNumber::kMantissaOffset));
+      // Return zero equal if all bits in mantissa is zero (it's an Infinity)
+      // and non-zero if not (it's a NaN).
+      __ ret(0);
+
+      __ bind(&not_identical);
+    }
+
+    // If we're doing a strict equality comparison, we don't have to do
+    // type conversion, so we generate code to do fast comparison for objects
+    // and oddballs. Non-smi numbers and strings still go through the usual
+    // slow-case code.
+    if (strict_) {
+      // If either is a Smi (we know that not both are), then they can only
+      // be equal if the other is a HeapNumber. If so, use the slow case.
+      {
+        Label not_smis;
+        ASSERT_EQ(0, kSmiTag);
+        ASSERT_EQ(0, Smi::FromInt(0));
+        __ mov(ecx, Immediate(kSmiTagMask));
+        __ and_(ecx, Operand(eax));
+        __ test(ecx, Operand(edx));
+        __ j(not_zero, &not_smis);
+        // One operand is a smi.
+
+        // Check whether the non-smi is a heap number.
+        ASSERT_EQ(1, kSmiTagMask);
+        // ecx still holds eax & kSmiTag, which is either zero or one.
+        __ sub(Operand(ecx), Immediate(0x01));
+        __ mov(ebx, edx);
+        __ xor_(ebx, Operand(eax));
+        __ and_(ebx, Operand(ecx));  // ebx holds either 0 or eax ^ edx.
+        __ xor_(ebx, Operand(eax));
+        // if eax was smi, ebx is now edx, else eax.
+
+        // Check if the non-smi operand is a heap number.
+        __ cmp(FieldOperand(ebx, HeapObject::kMapOffset),
+               Immediate(Factory::heap_number_map()));
+        // If heap number, handle it in the slow case.
+        __ j(equal, &slow);
+        // Return non-equal (ebx is not zero)
+        __ mov(eax, ebx);
+        __ ret(0);
+
+        __ bind(&not_smis);
+      }
+
+      // If either operand is a JSObject or an oddball value, then they are not
+      // equal since their pointers are different
+      // There is no test for undetectability in strict equality.
+
+      // Get the type of the first operand.
+      __ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
+      __ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
+
+      // If the first object is a JS object, we have done pointer comparison.
+      ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
+      Label first_non_object;
+      __ cmp(ecx, FIRST_JS_OBJECT_TYPE);
+      __ j(less, &first_non_object);
+
+      // Return non-zero (eax is not zero)
+      Label return_not_equal;
+      ASSERT(kHeapObjectTag != 0);
+      __ bind(&return_not_equal);
+      __ ret(0);
+
+      __ bind(&first_non_object);
+      // Check for oddballs: true, false, null, undefined.
+      __ cmp(ecx, ODDBALL_TYPE);
+      __ j(equal, &return_not_equal);
+
+      __ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
+      __ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
+
+      __ cmp(ecx, FIRST_JS_OBJECT_TYPE);
+      __ j(greater_equal, &return_not_equal);
+
+      // Check for oddballs: true, false, null, undefined.
+      __ cmp(ecx, ODDBALL_TYPE);
+      __ j(equal, &return_not_equal);
+
+      // Fall through to the general case.
+    }
+    __ bind(&slow);
+  }
+
+  // Push arguments below the return address.
+  __ pop(ecx);
+  __ push(eax);
+  __ push(edx);
+  __ push(ecx);
+
+  // Inlined floating point compare.
+  // Call builtin if operands are not floating point or smi.
+  Label check_for_symbols;
+  Label unordered;
+  if (CpuFeatures::IsSupported(CpuFeatures::SSE2)) {
+    CpuFeatures::Scope use_sse2(CpuFeatures::SSE2);
+    CpuFeatures::Scope use_cmov(CpuFeatures::CMOV);
+
+    FloatingPointHelper::LoadSse2Operands(masm, &check_for_symbols);
+    __ comisd(xmm0, xmm1);
+
+    // Jump to builtin for NaN.
+    __ j(parity_even, &unordered, not_taken);
+    __ mov(eax, 0);  // equal
+    __ mov(ecx, Immediate(Smi::FromInt(1)));
+    __ cmov(above, eax, Operand(ecx));
+    __ mov(ecx, Immediate(Smi::FromInt(-1)));
+    __ cmov(below, eax, Operand(ecx));
+    __ ret(2 * kPointerSize);
+  } else {
+    FloatingPointHelper::CheckFloatOperands(masm, &check_for_symbols, ebx);
+    FloatingPointHelper::LoadFloatOperands(masm, ecx);
+    __ FCmp();
+
+    // Jump to builtin for NaN.
+    __ j(parity_even, &unordered, not_taken);
+
+    Label below_lbl, above_lbl;
+    // Return a result of -1, 0, or 1, to indicate result of comparison.
+    __ j(below, &below_lbl, not_taken);
+    __ j(above, &above_lbl, not_taken);
+
+    __ xor_(eax, Operand(eax));  // equal
+    // Both arguments were pushed in case a runtime call was needed.
+    __ ret(2 * kPointerSize);
+
+    __ bind(&below_lbl);
+    __ mov(eax, Immediate(Smi::FromInt(-1)));
+    __ ret(2 * kPointerSize);
+
+    __ bind(&above_lbl);
+    __ mov(eax, Immediate(Smi::FromInt(1)));
+    __ ret(2 * kPointerSize);  // eax, edx were pushed
+  }
+  // If one of the numbers was NaN, then the result is always false.
+  // The cc is never not-equal.
+  __ bind(&unordered);
+  ASSERT(cc_ != not_equal);
+  if (cc_ == less || cc_ == less_equal) {
+    __ mov(eax, Immediate(Smi::FromInt(1)));
+  } else {
+    __ mov(eax, Immediate(Smi::FromInt(-1)));
+  }
+  __ ret(2 * kPointerSize);  // eax, edx were pushed
+
+  // Fast negative check for symbol-to-symbol equality.
+  __ bind(&check_for_symbols);
+  if (cc_ == equal) {
+    BranchIfNonSymbol(masm, &call_builtin, eax, ecx);
+    BranchIfNonSymbol(masm, &call_builtin, edx, ecx);
+
+    // We've already checked for object identity, so if both operands
+    // are symbols they aren't equal. Register eax already holds a
+    // non-zero value, which indicates not equal, so just return.
+    __ ret(2 * kPointerSize);
+  }
+
+  __ bind(&call_builtin);
+  // must swap argument order
+  __ pop(ecx);
+  __ pop(edx);
+  __ pop(eax);
+  __ push(edx);
+  __ push(eax);
+
+  // Figure out which native to call and setup the arguments.
+  Builtins::JavaScript builtin;
+  if (cc_ == equal) {
+    builtin = strict_ ? Builtins::STRICT_EQUALS : Builtins::EQUALS;
+  } else {
+    builtin = Builtins::COMPARE;
+    int ncr;  // NaN compare result
+    if (cc_ == less || cc_ == less_equal) {
+      ncr = GREATER;
+    } else {
+      ASSERT(cc_ == greater || cc_ == greater_equal);  // remaining cases
+      ncr = LESS;
+    }
+    __ push(Immediate(Smi::FromInt(ncr)));
+  }
+
+  // Restore return address on the stack.
+  __ push(ecx);
+
+  // Call the native; it returns -1 (less), 0 (equal), or 1 (greater)
+  // tagged as a small integer.
+  __ InvokeBuiltin(builtin, JUMP_FUNCTION);
+}
+
+
+void CompareStub::BranchIfNonSymbol(MacroAssembler* masm,
+                                    Label* label,
+                                    Register object,
+                                    Register scratch) {
+  __ test(object, Immediate(kSmiTagMask));
+  __ j(zero, label);
+  __ mov(scratch, FieldOperand(object, HeapObject::kMapOffset));
+  __ movzx_b(scratch, FieldOperand(scratch, Map::kInstanceTypeOffset));
+  __ and_(scratch, kIsSymbolMask | kIsNotStringMask);
+  __ cmp(scratch, kSymbolTag | kStringTag);
+  __ j(not_equal, label);
+}
+
+
+void StackCheckStub::Generate(MacroAssembler* masm) {
+  // Because builtins always remove the receiver from the stack, we
+  // have to fake one to avoid underflowing the stack. The receiver
+  // must be inserted below the return address on the stack so we
+  // temporarily store that in a register.
+  __ pop(eax);
+  __ push(Immediate(Smi::FromInt(0)));
+  __ push(eax);
+
+  // Do tail-call to runtime routine.
+  __ TailCallRuntime(ExternalReference(Runtime::kStackGuard), 1, 1);
+}
+
+
+void CallFunctionStub::Generate(MacroAssembler* masm) {
+  Label slow;
+
+  // Get the function to call from the stack.
+  // +2 ~ receiver, return address
+  __ mov(edi, Operand(esp, (argc_ + 2) * kPointerSize));
+
+  // Check that the function really is a JavaScript function.
+  __ test(edi, Immediate(kSmiTagMask));
+  __ j(zero, &slow, not_taken);
+  // Goto slow case if we do not have a function.
+  __ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
+  __ j(not_equal, &slow, not_taken);
+
+  // Fast-case: Just invoke the function.
+  ParameterCount actual(argc_);
+  __ InvokeFunction(edi, actual, JUMP_FUNCTION);
+
+  // Slow-case: Non-function called.
+  __ bind(&slow);
+  __ Set(eax, Immediate(argc_));
+  __ Set(ebx, Immediate(0));
+  __ GetBuiltinEntry(edx, Builtins::CALL_NON_FUNCTION);
+  Handle<Code> adaptor(Builtins::builtin(Builtins::ArgumentsAdaptorTrampoline));
+  __ jmp(adaptor, RelocInfo::CODE_TARGET);
+}
+
+
+int CEntryStub::MinorKey() {
+  ASSERT(result_size_ <= 2);
+  // Result returned in eax, or eax+edx if result_size_ is 2.
+  return 0;
+}
+
+
+void CEntryStub::GenerateThrowTOS(MacroAssembler* masm) {
+  // eax holds the exception.
+
+  // Adjust this code if not the case.
+  ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
+
+  // Drop the sp to the top of the handler.
+  ExternalReference handler_address(Top::k_handler_address);
+  __ mov(esp, Operand::StaticVariable(handler_address));
+
+  // Restore next handler and frame pointer, discard handler state.
+  ASSERT(StackHandlerConstants::kNextOffset == 0);
+  __ pop(Operand::StaticVariable(handler_address));
+  ASSERT(StackHandlerConstants::kFPOffset == 1 * kPointerSize);
+  __ pop(ebp);
+  __ pop(edx);  // Remove state.
+
+  // Before returning we restore the context from the frame pointer if
+  // not NULL.  The frame pointer is NULL in the exception handler of
+  // a JS entry frame.
+  __ xor_(esi, Operand(esi));  // Tentatively set context pointer to NULL.
+  Label skip;
+  __ cmp(ebp, 0);
+  __ j(equal, &skip, not_taken);
+  __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
+  __ bind(&skip);
+
+  ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
+  __ ret(0);
+}
+
+
+void CEntryStub::GenerateCore(MacroAssembler* masm,
+                              Label* throw_normal_exception,
+                              Label* throw_termination_exception,
+                              Label* throw_out_of_memory_exception,
+                              StackFrame::Type frame_type,
+                              bool do_gc,
+                              bool always_allocate_scope) {
+  // eax: result parameter for PerformGC, if any
+  // ebx: pointer to C function  (C callee-saved)
+  // ebp: frame pointer  (restored after C call)
+  // esp: stack pointer  (restored after C call)
+  // edi: number of arguments including receiver  (C callee-saved)
+  // esi: pointer to the first argument (C callee-saved)
+
+  if (do_gc) {
+    __ mov(Operand(esp, 0 * kPointerSize), eax);  // Result.
+    __ call(FUNCTION_ADDR(Runtime::PerformGC), RelocInfo::RUNTIME_ENTRY);
+  }
+
+  ExternalReference scope_depth =
+      ExternalReference::heap_always_allocate_scope_depth();
+  if (always_allocate_scope) {
+    __ inc(Operand::StaticVariable(scope_depth));
+  }
+
+  // Call C function.
+  __ mov(Operand(esp, 0 * kPointerSize), edi);  // argc.
+  __ mov(Operand(esp, 1 * kPointerSize), esi);  // argv.
+  __ call(Operand(ebx));
+  // Result is in eax or edx:eax - do not destroy these registers!
+
+  if (always_allocate_scope) {
+    __ dec(Operand::StaticVariable(scope_depth));
+  }
+
+  // Make sure we're not trying to return 'the hole' from the runtime
+  // call as this may lead to crashes in the IC code later.
+  if (FLAG_debug_code) {
+    Label okay;
+    __ cmp(eax, Factory::the_hole_value());
+    __ j(not_equal, &okay);
+    __ int3();
+    __ bind(&okay);
+  }
+
+  // Check for failure result.
+  Label failure_returned;
+  ASSERT(((kFailureTag + 1) & kFailureTagMask) == 0);
+  __ lea(ecx, Operand(eax, 1));
+  // Lower 2 bits of ecx are 0 iff eax has failure tag.
+  __ test(ecx, Immediate(kFailureTagMask));
+  __ j(zero, &failure_returned, not_taken);
+
+  // Exit the JavaScript to C++ exit frame.
+  __ LeaveExitFrame(frame_type);
+  __ ret(0);
+
+  // Handling of failure.
+  __ bind(&failure_returned);
+
+  Label retry;
+  // If the returned exception is RETRY_AFTER_GC continue at retry label
+  ASSERT(Failure::RETRY_AFTER_GC == 0);
+  __ test(eax, Immediate(((1 << kFailureTypeTagSize) - 1) << kFailureTagSize));
+  __ j(zero, &retry, taken);
+
+  // Special handling of out of memory exceptions.
+  __ cmp(eax, reinterpret_cast<int32_t>(Failure::OutOfMemoryException()));
+  __ j(equal, throw_out_of_memory_exception);
+
+  // Retrieve the pending exception and clear the variable.
+  ExternalReference pending_exception_address(Top::k_pending_exception_address);
+  __ mov(eax, Operand::StaticVariable(pending_exception_address));
+  __ mov(edx,
+         Operand::StaticVariable(ExternalReference::the_hole_value_location()));
+  __ mov(Operand::StaticVariable(pending_exception_address), edx);
+
+  // Special handling of termination exceptions which are uncatchable
+  // by javascript code.
+  __ cmp(eax, Factory::termination_exception());
+  __ j(equal, throw_termination_exception);
+
+  // Handle normal exception.
+  __ jmp(throw_normal_exception);
+
+  // Retry.
+  __ bind(&retry);
+}
+
+
+void CEntryStub::GenerateThrowUncatchable(MacroAssembler* masm,
+                                          UncatchableExceptionType type) {
+  // Adjust this code if not the case.
+  ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
+
+  // Drop sp to the top stack handler.
+  ExternalReference handler_address(Top::k_handler_address);
+  __ mov(esp, Operand::StaticVariable(handler_address));
+
+  // Unwind the handlers until the ENTRY handler is found.
+  Label loop, done;
+  __ bind(&loop);
+  // Load the type of the current stack handler.
+  const int kStateOffset = StackHandlerConstants::kStateOffset;
+  __ cmp(Operand(esp, kStateOffset), Immediate(StackHandler::ENTRY));
+  __ j(equal, &done);
+  // Fetch the next handler in the list.
+  const int kNextOffset = StackHandlerConstants::kNextOffset;
+  __ mov(esp, Operand(esp, kNextOffset));
+  __ jmp(&loop);
+  __ bind(&done);
+
+  // Set the top handler address to next handler past the current ENTRY handler.
+  ASSERT(StackHandlerConstants::kNextOffset == 0);
+  __ pop(Operand::StaticVariable(handler_address));
+
+  if (type == OUT_OF_MEMORY) {
+    // Set external caught exception to false.
+    ExternalReference external_caught(Top::k_external_caught_exception_address);
+    __ mov(eax, false);
+    __ mov(Operand::StaticVariable(external_caught), eax);
+
+    // Set pending exception and eax to out of memory exception.
+    ExternalReference pending_exception(Top::k_pending_exception_address);
+    __ mov(eax, reinterpret_cast<int32_t>(Failure::OutOfMemoryException()));
+    __ mov(Operand::StaticVariable(pending_exception), eax);
+  }
+
+  // Clear the context pointer.
+  __ xor_(esi, Operand(esi));
+
+  // Restore fp from handler and discard handler state.
+  ASSERT(StackHandlerConstants::kFPOffset == 1 * kPointerSize);
+  __ pop(ebp);
+  __ pop(edx);  // State.
+
+  ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
+  __ ret(0);
+}
+
+
+void CEntryStub::GenerateBody(MacroAssembler* masm, bool is_debug_break) {
+  // eax: number of arguments including receiver
+  // ebx: pointer to C function  (C callee-saved)
+  // ebp: frame pointer  (restored after C call)
+  // esp: stack pointer  (restored after C call)
+  // esi: current context (C callee-saved)
+  // edi: JS function of the caller (C callee-saved)
+
+  // NOTE: Invocations of builtins may return failure objects instead
+  // of a proper result. The builtin entry handles this by performing
+  // a garbage collection and retrying the builtin (twice).
+
+  StackFrame::Type frame_type = is_debug_break ?
+      StackFrame::EXIT_DEBUG :
+      StackFrame::EXIT;
+
+  // Enter the exit frame that transitions from JavaScript to C++.
+  __ EnterExitFrame(frame_type);
+
+  // eax: result parameter for PerformGC, if any (setup below)
+  // ebx: pointer to builtin function  (C callee-saved)
+  // ebp: frame pointer  (restored after C call)
+  // esp: stack pointer  (restored after C call)
+  // edi: number of arguments including receiver (C callee-saved)
+  // esi: argv pointer (C callee-saved)
+
+  Label throw_normal_exception;
+  Label throw_termination_exception;
+  Label throw_out_of_memory_exception;
+
+  // Call into the runtime system.
+  GenerateCore(masm,
+               &throw_normal_exception,
+               &throw_termination_exception,
+               &throw_out_of_memory_exception,
+               frame_type,
+               false,
+               false);
+
+  // Do space-specific GC and retry runtime call.
+  GenerateCore(masm,
+               &throw_normal_exception,
+               &throw_termination_exception,
+               &throw_out_of_memory_exception,
+               frame_type,
+               true,
+               false);
+
+  // Do full GC and retry runtime call one final time.
+  Failure* failure = Failure::InternalError();
+  __ mov(eax, Immediate(reinterpret_cast<int32_t>(failure)));
+  GenerateCore(masm,
+               &throw_normal_exception,
+               &throw_termination_exception,
+               &throw_out_of_memory_exception,
+               frame_type,
+               true,
+               true);
+
+  __ bind(&throw_out_of_memory_exception);
+  GenerateThrowUncatchable(masm, OUT_OF_MEMORY);
+
+  __ bind(&throw_termination_exception);
+  GenerateThrowUncatchable(masm, TERMINATION);
+
+  __ bind(&throw_normal_exception);
+  GenerateThrowTOS(masm);
+}
+
+
+void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
+  Label invoke, exit;
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  Label not_outermost_js, not_outermost_js_2;
+#endif
+
+  // Setup frame.
+  __ push(ebp);
+  __ mov(ebp, Operand(esp));
+
+  // Push marker in two places.
+  int marker = is_construct ? StackFrame::ENTRY_CONSTRUCT : StackFrame::ENTRY;
+  __ push(Immediate(Smi::FromInt(marker)));  // context slot
+  __ push(Immediate(Smi::FromInt(marker)));  // function slot
+  // Save callee-saved registers (C calling conventions).
+  __ push(edi);
+  __ push(esi);
+  __ push(ebx);
+
+  // Save copies of the top frame descriptor on the stack.
+  ExternalReference c_entry_fp(Top::k_c_entry_fp_address);
+  __ push(Operand::StaticVariable(c_entry_fp));
+
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  // If this is the outermost JS call, set js_entry_sp value.
+  ExternalReference js_entry_sp(Top::k_js_entry_sp_address);
+  __ cmp(Operand::StaticVariable(js_entry_sp), Immediate(0));
+  __ j(not_equal, &not_outermost_js);
+  __ mov(Operand::StaticVariable(js_entry_sp), ebp);
+  __ bind(&not_outermost_js);
+#endif
+
+  // Call a faked try-block that does the invoke.
+  __ call(&invoke);
+
+  // Caught exception: Store result (exception) in the pending
+  // exception field in the JSEnv and return a failure sentinel.
+  ExternalReference pending_exception(Top::k_pending_exception_address);
+  __ mov(Operand::StaticVariable(pending_exception), eax);
+  __ mov(eax, reinterpret_cast<int32_t>(Failure::Exception()));
+  __ jmp(&exit);
+
+  // Invoke: Link this frame into the handler chain.
+  __ bind(&invoke);
+  __ PushTryHandler(IN_JS_ENTRY, JS_ENTRY_HANDLER);
+
+  // Clear any pending exceptions.
+  __ mov(edx,
+         Operand::StaticVariable(ExternalReference::the_hole_value_location()));
+  __ mov(Operand::StaticVariable(pending_exception), edx);
+
+  // Fake a receiver (NULL).
+  __ push(Immediate(0));  // receiver
+
+  // Invoke the function by calling through JS entry trampoline
+  // builtin and pop the faked function when we return. Notice that we
+  // cannot store a reference to the trampoline code directly in this
+  // stub, because the builtin stubs may not have been generated yet.
+  if (is_construct) {
+    ExternalReference construct_entry(Builtins::JSConstructEntryTrampoline);
+    __ mov(edx, Immediate(construct_entry));
+  } else {
+    ExternalReference entry(Builtins::JSEntryTrampoline);
+    __ mov(edx, Immediate(entry));
+  }
+  __ mov(edx, Operand(edx, 0));  // deref address
+  __ lea(edx, FieldOperand(edx, Code::kHeaderSize));
+  __ call(Operand(edx));
+
+  // Unlink this frame from the handler chain.
+  __ pop(Operand::StaticVariable(ExternalReference(Top::k_handler_address)));
+  // Pop next_sp.
+  __ add(Operand(esp), Immediate(StackHandlerConstants::kSize - kPointerSize));
+
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  // If current EBP value is the same as js_entry_sp value, it means that
+  // the current function is the outermost.
+  __ cmp(ebp, Operand::StaticVariable(js_entry_sp));
+  __ j(not_equal, &not_outermost_js_2);
+  __ mov(Operand::StaticVariable(js_entry_sp), Immediate(0));
+  __ bind(&not_outermost_js_2);
+#endif
+
+  // Restore the top frame descriptor from the stack.
+  __ bind(&exit);
+  __ pop(Operand::StaticVariable(ExternalReference(Top::k_c_entry_fp_address)));
+
+  // Restore callee-saved registers (C calling conventions).
+  __ pop(ebx);
+  __ pop(esi);
+  __ pop(edi);
+  __ add(Operand(esp), Immediate(2 * kPointerSize));  // remove markers
+
+  // Restore frame pointer and return.
+  __ pop(ebp);
+  __ ret(0);
+}
+
+
+void InstanceofStub::Generate(MacroAssembler* masm) {
+  // Get the object - go slow case if it's a smi.
+  Label slow;
+  __ mov(eax, Operand(esp, 2 * kPointerSize));  // 2 ~ return address, function
+  __ test(eax, Immediate(kSmiTagMask));
+  __ j(zero, &slow, not_taken);
+
+  // Check that the left hand is a JS object.
+  __ mov(eax, FieldOperand(eax, HeapObject::kMapOffset));  // eax - object map
+  __ movzx_b(ecx, FieldOperand(eax, Map::kInstanceTypeOffset));  // ecx - type
+  __ cmp(ecx, FIRST_JS_OBJECT_TYPE);
+  __ j(less, &slow, not_taken);
+  __ cmp(ecx, LAST_JS_OBJECT_TYPE);
+  __ j(greater, &slow, not_taken);
+
+  // Get the prototype of the function.
+  __ mov(edx, Operand(esp, 1 * kPointerSize));  // 1 ~ return address
+  __ TryGetFunctionPrototype(edx, ebx, ecx, &slow);
+
+  // Check that the function prototype is a JS object.
+  __ test(ebx, Immediate(kSmiTagMask));
+  __ j(zero, &slow, not_taken);
+  __ mov(ecx, FieldOperand(ebx, HeapObject::kMapOffset));
+  __ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
+  __ cmp(ecx, FIRST_JS_OBJECT_TYPE);
+  __ j(less, &slow, not_taken);
+  __ cmp(ecx, LAST_JS_OBJECT_TYPE);
+  __ j(greater, &slow, not_taken);
+
+  // Register mapping: eax is object map and ebx is function prototype.
+  __ mov(ecx, FieldOperand(eax, Map::kPrototypeOffset));
+
+  // Loop through the prototype chain looking for the function prototype.
+  Label loop, is_instance, is_not_instance;
+  __ bind(&loop);
+  __ cmp(ecx, Operand(ebx));
+  __ j(equal, &is_instance);
+  __ cmp(Operand(ecx), Immediate(Factory::null_value()));
+  __ j(equal, &is_not_instance);
+  __ mov(ecx, FieldOperand(ecx, HeapObject::kMapOffset));
+  __ mov(ecx, FieldOperand(ecx, Map::kPrototypeOffset));
+  __ jmp(&loop);
+
+  __ bind(&is_instance);
+  __ Set(eax, Immediate(0));
+  __ ret(2 * kPointerSize);
+
+  __ bind(&is_not_instance);
+  __ Set(eax, Immediate(Smi::FromInt(1)));
+  __ ret(2 * kPointerSize);
+
+  // Slow-case: Go through the JavaScript implementation.
+  __ bind(&slow);
+  __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
+}
+
+
+int CompareStub::MinorKey() {
+  // Encode the two parameters in a unique 16 bit value.
+  ASSERT(static_cast<unsigned>(cc_) < (1 << 15));
+  return (static_cast<unsigned>(cc_) << 1) | (strict_ ? 1 : 0);
+}
+
+#undef __
+
+} }  // namespace v8::internal