text: // Copyright 2012 the V8 project authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "src/v8.h"
  
  #if V8_TARGET_ARCH_MIPS
  
  // Note on Mips implementation:
  //
  // The result_register() for mips is the 'v0' register, which is defined
  // by the ABI to contain function return values. However, the first
  // parameter to a function is defined to be 'a0'. So there are many
  // places where we have to move a previous result in v0 to a0 for the
  // next call: mov(a0, v0). This is not needed on the other architectures.
  
  #include "src/code-factory.h"
  #include "src/code-stubs.h"
  #include "src/codegen.h"
  #include "src/compiler.h"
  #include "src/debug.h"
  #include "src/full-codegen.h"
  #include "src/ic/ic.h"
  #include "src/isolate-inl.h"
  #include "src/parser.h"
  #include "src/scopes.h"
  
  #include "src/mips/code-stubs-mips.h"
  #include "src/mips/macro-assembler-mips.h"
  
  namespace v8 {
  namespace internal {
  
  #define __ ACCESS_MASM(masm_)
  
  
  // A patch site is a location in the code which it is possible to patch. This
  // class has a number of methods to emit the code which is patchable and the
  // method EmitPatchInfo to record a marker back to the patchable code. This
  // marker is a andi zero_reg, rx, #yyyy instruction, and rx * 0x0000ffff + yyyy
  // (raw 16 bit immediate value is used) is the delta from the pc to the first
  // instruction of the patchable code.
  // The marker instruction is effectively a NOP (dest is zero_reg) and will
  // never be emitted by normal code.
  class JumpPatchSite BASE_EMBEDDED {
   public:
    explicit JumpPatchSite(MacroAssembler* masm) : masm_(masm) {
  #ifdef DEBUG
      info_emitted_ = false;
  #endif
    }
  
    ~JumpPatchSite() {
      DCHECK(patch_site_.is_bound() == info_emitted_);
    }
  
    // When initially emitting this ensure that a jump is always generated to skip
    // the inlined smi code.
    void EmitJumpIfNotSmi(Register reg, Label* target) {
      DCHECK(!patch_site_.is_bound() && !info_emitted_);
      Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm_);
      __ bind(&patch_site_);
      __ andi(at, reg, 0);
      // Always taken before patched.
      __ BranchShort(target, eq, at, Operand(zero_reg));
    }
  
    // When initially emitting this ensure that a jump is never generated to skip
    // the inlined smi code.
    void EmitJumpIfSmi(Register reg, Label* target) {
      Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm_);
      DCHECK(!patch_site_.is_bound() && !info_emitted_);
      __ bind(&patch_site_);
      __ andi(at, reg, 0);
      // Never taken before patched.
      __ BranchShort(target, ne, at, Operand(zero_reg));
    }
  
    void EmitPatchInfo() {
      if (patch_site_.is_bound()) {
        int delta_to_patch_site = masm_->InstructionsGeneratedSince(&patch_site_);
        Register reg = Register::from_code(delta_to_patch_site / kImm16Mask);
        __ andi(zero_reg, reg, delta_to_patch_site % kImm16Mask);
  #ifdef DEBUG
        info_emitted_ = true;
  #endif
      } else {
        __ nop();  // Signals no inlined code.
      }
    }
  
   private:
    MacroAssembler* masm_;
    Label patch_site_;
  #ifdef DEBUG
    bool info_emitted_;
  #endif
  };
  
  
  // Generate code for a JS function.  On entry to the function the receiver
  // and arguments have been pushed on the stack left to right.  The actual
  // argument count matches the formal parameter count expected by the
  // function.
  //
  // The live registers are:
  //   o a1: the JS function object being called (i.e. ourselves)
  //   o cp: our context
  //   o fp: our caller's frame pointer
  //   o sp: stack pointer
  //   o ra: return address
  //
  // The function builds a JS frame.  Please see JavaScriptFrameConstants in
  // frames-mips.h for its layout.
  void FullCodeGenerator::Generate() {
    CompilationInfo* info = info_;
    handler_table_ =
        isolate()->factory()->NewFixedArray(function()->handler_count(), TENURED);
  
    profiling_counter_ = isolate()->factory()->NewCell(
        Handle<Smi>(Smi::FromInt(FLAG_interrupt_budget), isolate()));
    SetFunctionPosition(function());
    Comment cmnt(masm_, "[ function compiled by full code generator");
  
    ProfileEntryHookStub::MaybeCallEntryHook(masm_);
  
  #ifdef DEBUG
    if (strlen(FLAG_stop_at) > 0 &&
        info->function()->name()->IsUtf8EqualTo(CStrVector(FLAG_stop_at))) {
      __ stop("stop-at");
    }
  #endif
  
    // Sloppy mode functions and builtins need to replace the receiver with the
    // global proxy when called as functions (without an explicit receiver
    // object).
    if (info->strict_mode() == SLOPPY && !info->is_native()) {
      Label ok;
      int receiver_offset = info->scope()->num_parameters() * kPointerSize;
      __ lw(at, MemOperand(sp, receiver_offset));
      __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
      __ Branch(&ok, ne, a2, Operand(at));
  
      __ lw(a2, GlobalObjectOperand());
      __ lw(a2, FieldMemOperand(a2, GlobalObject::kGlobalProxyOffset));
  
      __ sw(a2, MemOperand(sp, receiver_offset));
  
      __ bind(&ok);
    }
  
    // Open a frame scope to indicate that there is a frame on the stack.  The
    // MANUAL indicates that the scope shouldn't actually generate code to set up
    // the frame (that is done below).
    FrameScope frame_scope(masm_, StackFrame::MANUAL);
  
    info->set_prologue_offset(masm_->pc_offset());
    __ Prologue(info->IsCodePreAgingActive());
    info->AddNoFrameRange(0, masm_->pc_offset());
  
    { Comment cmnt(masm_, "[ Allocate locals");
      int locals_count = info->scope()->num_stack_slots();
      // Generators allocate locals, if any, in context slots.
      DCHECK(!info->function()->is_generator() || locals_count == 0);
      if (locals_count > 0) {
        if (locals_count >= 128) {
          Label ok;
          __ Subu(t5, sp, Operand(locals_count * kPointerSize));
          __ LoadRoot(a2, Heap::kRealStackLimitRootIndex);
          __ Branch(&ok, hs, t5, Operand(a2));
          __ InvokeBuiltin(Builtins::STACK_OVERFLOW, CALL_FUNCTION);
          __ bind(&ok);
        }
        __ LoadRoot(t5, Heap::kUndefinedValueRootIndex);
        int kMaxPushes = FLAG_optimize_for_size ? 4 : 32;
        if (locals_count >= kMaxPushes) {
          int loop_iterations = locals_count / kMaxPushes;
          __ li(a2, Operand(loop_iterations));
          Label loop_header;
          __ bind(&loop_header);
          // Do pushes.
          __ Subu(sp, sp, Operand(kMaxPushes * kPointerSize));
          for (int i = 0; i < kMaxPushes; i++) {
            __ sw(t5, MemOperand(sp, i * kPointerSize));
          }
          // Continue loop if not done.
          __ Subu(a2, a2, Operand(1));
          __ Branch(&loop_header, ne, a2, Operand(zero_reg));
        }
        int remaining = locals_count % kMaxPushes;
        // Emit the remaining pushes.
        __ Subu(sp, sp, Operand(remaining * kPointerSize));
        for (int i  = 0; i < remaining; i++) {
          __ sw(t5, MemOperand(sp, i * kPointerSize));
        }
      }
    }
  
    bool function_in_register = true;
  
    // Possibly allocate a local context.
    int heap_slots = info->scope()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
    if (heap_slots > 0) {
      Comment cmnt(masm_, "[ Allocate context");
      // Argument to NewContext is the function, which is still in a1.
      bool need_write_barrier = true;
      if (FLAG_harmony_scoping && info->scope()->is_global_scope()) {
        __ push(a1);
        __ Push(info->scope()->GetScopeInfo());
        __ CallRuntime(Runtime::kNewGlobalContext, 2);
      } else if (heap_slots <= FastNewContextStub::kMaximumSlots) {
        FastNewContextStub stub(isolate(), heap_slots);
        __ CallStub(&stub);
        // Result of FastNewContextStub is always in new space.
        need_write_barrier = false;
      } else {
        __ push(a1);
        __ CallRuntime(Runtime::kNewFunctionContext, 1);
      }
      function_in_register = false;
      // Context is returned in v0. It replaces the context passed to us.
      // It's saved in the stack and kept live in cp.
      __ mov(cp, v0);
      __ sw(v0, MemOperand(fp, StandardFrameConstants::kContextOffset));
      // Copy any necessary parameters into the context.
      int num_parameters = info->scope()->num_parameters();
      for (int i = 0; i < num_parameters; i++) {
        Variable* var = scope()->parameter(i);
        if (var->IsContextSlot()) {
          int parameter_offset = StandardFrameConstants::kCallerSPOffset +
                                   (num_parameters - 1 - i) * kPointerSize;
          // Load parameter from stack.
          __ lw(a0, MemOperand(fp, parameter_offset));
          // Store it in the context.
          MemOperand target = ContextOperand(cp, var->index());
          __ sw(a0, target);
  
          // Update the write barrier.
          if (need_write_barrier) {
            __ RecordWriteContextSlot(
                cp, target.offset(), a0, a3, kRAHasBeenSaved, kDontSaveFPRegs);
          } else if (FLAG_debug_code) {
            Label done;
            __ JumpIfInNewSpace(cp, a0, &done);
            __ Abort(kExpectedNewSpaceObject);
            __ bind(&done);
          }
        }
      }
    }
  
    Variable* arguments = scope()->arguments();
    if (arguments != NULL) {
      // Function uses arguments object.
      Comment cmnt(masm_, "[ Allocate arguments object");
      if (!function_in_register) {
        // Load this again, if it's used by the local context below.
        __ lw(a3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
      } else {
        __ mov(a3, a1);
      }
      // Receiver is just before the parameters on the caller's stack.
      int num_parameters = info->scope()->num_parameters();
      int offset = num_parameters * kPointerSize;
      __ Addu(a2, fp,
             Operand(StandardFrameConstants::kCallerSPOffset + offset));
      __ li(a1, Operand(Smi::FromInt(num_parameters)));
      __ Push(a3, a2, a1);
  
      // Arguments to ArgumentsAccessStub:
      //   function, receiver address, parameter count.
      // The stub will rewrite receiever and parameter count if the previous
      // stack frame was an arguments adapter frame.
      ArgumentsAccessStub::Type type;
      if (strict_mode() == STRICT) {
        type = ArgumentsAccessStub::NEW_STRICT;
      } else if (function()->has_duplicate_parameters()) {
        type = ArgumentsAccessStub::NEW_SLOPPY_SLOW;
      } else {
        type = ArgumentsAccessStub::NEW_SLOPPY_FAST;
      }
      ArgumentsAccessStub stub(isolate(), type);
      __ CallStub(&stub);
  
      SetVar(arguments, v0, a1, a2);
    }
  
    if (FLAG_trace) {
      __ CallRuntime(Runtime::kTraceEnter, 0);
    }
  
    // Visit the declarations and body unless there is an illegal
    // redeclaration.
    if (scope()->HasIllegalRedeclaration()) {
      Comment cmnt(masm_, "[ Declarations");
      scope()->VisitIllegalRedeclaration(this);
  
    } else {
      PrepareForBailoutForId(BailoutId::FunctionEntry(), NO_REGISTERS);
      { Comment cmnt(masm_, "[ Declarations");
        // For named function expressions, declare the function name as a
        // constant.
        if (scope()->is_function_scope() && scope()->function() != NULL) {
          VariableDeclaration* function = scope()->function();
          DCHECK(function->proxy()->var()->mode() == CONST ||
                 function->proxy()->var()->mode() == CONST_LEGACY);
          DCHECK(function->proxy()->var()->location() != Variable::UNALLOCATED);
          VisitVariableDeclaration(function);
        }
        VisitDeclarations(scope()->declarations());
      }
  
      { Comment cmnt(masm_, "[ Stack check");
        PrepareForBailoutForId(BailoutId::Declarations(), NO_REGISTERS);
        Label ok;
        __ LoadRoot(at, Heap::kStackLimitRootIndex);
        __ Branch(&ok, hs, sp, Operand(at));
        Handle<Code> stack_check = isolate()->builtins()->StackCheck();
        PredictableCodeSizeScope predictable(masm_,
            masm_->CallSize(stack_check, RelocInfo::CODE_TARGET));
        __ Call(stack_check, RelocInfo::CODE_TARGET);
        __ bind(&ok);
      }
  
      { Comment cmnt(masm_, "[ Body");
        DCHECK(loop_depth() == 0);
        VisitStatements(function()->body());
        DCHECK(loop_depth() == 0);
      }
    }
  
    // Always emit a 'return undefined' in case control fell off the end of
    // the body.
    { Comment cmnt(masm_, "[ return <undefined>;");
      __ LoadRoot(v0, Heap::kUndefinedValueRootIndex);
    }
    EmitReturnSequence();
  }
  
  
  void FullCodeGenerator::ClearAccumulator() {
    DCHECK(Smi::FromInt(0) == 0);
    __ mov(v0, zero_reg);
  }
  
  
  void FullCodeGenerator::EmitProfilingCounterDecrement(int delta) {
    __ li(a2, Operand(profiling_counter_));
    __ lw(a3, FieldMemOperand(a2, Cell::kValueOffset));
    __ Subu(a3, a3, Operand(Smi::FromInt(delta)));
    __ sw(a3, FieldMemOperand(a2, Cell::kValueOffset));
  }
  
  
  void FullCodeGenerator::EmitProfilingCounterReset() {
    int reset_value = FLAG_interrupt_budget;
    if (info_->is_debug()) {
      // Detect debug break requests as soon as possible.
      reset_value = FLAG_interrupt_budget >> 4;
    }
    __ li(a2, Operand(profiling_counter_));
    __ li(a3, Operand(Smi::FromInt(reset_value)));
    __ sw(a3, FieldMemOperand(a2, Cell::kValueOffset));
  }
  
  
  void FullCodeGenerator::EmitBackEdgeBookkeeping(IterationStatement* stmt,
                                                  Label* back_edge_target) {
    // The generated code is used in Deoptimizer::PatchStackCheckCodeAt so we need
    // to make sure it is constant. Branch may emit a skip-or-jump sequence
    // instead of the normal Branch. It seems that the "skip" part of that
    // sequence is about as long as this Branch would be so it is safe to ignore
    // that.
    Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm_);
    Comment cmnt(masm_, "[ Back edge bookkeeping");
    Label ok;
    DCHECK(back_edge_target->is_bound());
    int distance = masm_->SizeOfCodeGeneratedSince(back_edge_target);
    int weight = Min(kMaxBackEdgeWeight,
                     Max(1, distance / kCodeSizeMultiplier));
    EmitProfilingCounterDecrement(weight);
    __ slt(at, a3, zero_reg);
    __ beq(at, zero_reg, &ok);
    // Call will emit a li t9 first, so it is safe to use the delay slot.
    __ Call(isolate()->builtins()->InterruptCheck(), RelocInfo::CODE_TARGET);
    // Record a mapping of this PC offset to the OSR id.  This is used to find
    // the AST id from the unoptimized code in order to use it as a key into
    // the deoptimization input data found in the optimized code.
    RecordBackEdge(stmt->OsrEntryId());
    EmitProfilingCounterReset();
  
    __ bind(&ok);
    PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
    // Record a mapping of the OSR id to this PC.  This is used if the OSR
    // entry becomes the target of a bailout.  We don't expect it to be, but
    // we want it to work if it is.
    PrepareForBailoutForId(stmt->OsrEntryId(), NO_REGISTERS);
  }
  
  
  void FullCodeGenerator::EmitReturnSequence() {
    Comment cmnt(masm_, "[ Return sequence");
    if (return_label_.is_bound()) {
      __ Branch(&return_label_);
    } else {
      __ bind(&return_label_);
      if (FLAG_trace) {
        // Push the return value on the stack as the parameter.
        // Runtime::TraceExit returns its parameter in v0.
        __ push(v0);
        __ CallRuntime(Runtime::kTraceExit, 1);
      }
      // Pretend that the exit is a backwards jump to the entry.
      int weight = 1;
      if (info_->ShouldSelfOptimize()) {
        weight = FLAG_interrupt_budget / FLAG_self_opt_count;
      } else {
        int distance = masm_->pc_offset();
        weight = Min(kMaxBackEdgeWeight,
                     Max(1, distance / kCodeSizeMultiplier));
      }
      EmitProfilingCounterDecrement(weight);
      Label ok;
      __ Branch(&ok, ge, a3, Operand(zero_reg));
      __ push(v0);
      __ Call(isolate()->builtins()->InterruptCheck(),
              RelocInfo::CODE_TARGET);
      __ pop(v0);
      EmitProfilingCounterReset();
      __ bind(&ok);
  
  #ifdef DEBUG
      // Add a label for checking the size of the code used for returning.
      Label check_exit_codesize;
      masm_->bind(&check_exit_codesize);
  #endif
      // Make sure that the constant pool is not emitted inside of the return
      // sequence.
      { Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm_);
        // Here we use masm_-> instead of the __ macro to avoid the code coverage
        // tool from instrumenting as we rely on the code size here.
        int32_t sp_delta = (info_->scope()->num_parameters() + 1) * kPointerSize;
        CodeGenerator::RecordPositions(masm_, function()->end_position() - 1);
        __ RecordJSReturn();
        masm_->mov(sp, fp);
        int no_frame_start = masm_->pc_offset();
        masm_->MultiPop(static_cast<RegList>(fp.bit() | ra.bit()));
        masm_->Addu(sp, sp, Operand(sp_delta));
        masm_->Jump(ra);
        info_->AddNoFrameRange(no_frame_start, masm_->pc_offset());
      }
  
  #ifdef DEBUG
      // Check that the size of the code used for returning is large enough
      // for the debugger's requirements.
      DCHECK(Assembler::kJSReturnSequenceInstructions <=
             masm_->InstructionsGeneratedSince(&check_exit_codesize));
  #endif
    }
  }
  
  
  void FullCodeGenerator::EffectContext::Plug(Variable* var) const {
    DCHECK(var->IsStackAllocated() || var->IsContextSlot());
  }
  
  
  void FullCodeGenerator::AccumulatorValueContext::Plug(Variable* var) const {
    DCHECK(var->IsStackAllocated() || var->IsContextSlot());
    codegen()->GetVar(result_register(), var);
  }
  
  
  void FullCodeGenerator::StackValueContext::Plug(Variable* var) const {
    DCHECK(var->IsStackAllocated() || var->IsContextSlot());
    codegen()->GetVar(result_register(), var);
    __ push(result_register());
  }
  
  
  void FullCodeGenerator::TestContext::Plug(Variable* var) const {
    // For simplicity we always test the accumulator register.
    codegen()->GetVar(result_register(), var);
    codegen()->PrepareForBailoutBeforeSplit(condition(), false, NULL, NULL);
    codegen()->DoTest(this);
  }
  
  
  void FullCodeGenerator::EffectContext::Plug(Heap::RootListIndex index) const {
  }
  
  
  void FullCodeGenerator::AccumulatorValueContext::Plug(
      Heap::RootListIndex index) const {
    __ LoadRoot(result_register(), index);
  }
  
  
  void FullCodeGenerator::StackValueContext::Plug(
      Heap::RootListIndex index) const {
    __ LoadRoot(result_register(), index);
    __ push(result_register());
  }
  
  
  void FullCodeGenerator::TestContext::Plug(Heap::RootListIndex index) const {
    codegen()->PrepareForBailoutBeforeSplit(condition(),
                                            true,
                                            true_label_,
                                            false_label_);
    if (index == Heap::kUndefinedValueRootIndex ||
        index == Heap::kNullValueRootIndex ||
        index == Heap::kFalseValueRootIndex) {
      if (false_label_ != fall_through_) __ Branch(false_label_);
    } else if (index == Heap::kTrueValueRootIndex) {
      if (true_label_ != fall_through_) __ Branch(true_label_);
    } else {
      __ LoadRoot(result_register(), index);
      codegen()->DoTest(this);
    }
  }
  
  
  void FullCodeGenerator::EffectContext::Plug(Handle<Object> lit) const {
  }
  
  
  void FullCodeGenerator::AccumulatorValueContext::Plug(
      Handle<Object> lit) const {
    __ li(result_register(), Operand(lit));
  }
  
  
  void FullCodeGenerator::StackValueContext::Plug(Handle<Object> lit) const {
    // Immediates cannot be pushed directly.
    __ li(result_register(), Operand(lit));
    __ push(result_register());
  }
  
  
  void FullCodeGenerator::TestContext::Plug(Handle<Object> lit) const {
    codegen()->PrepareForBailoutBeforeSplit(condition(),
                                            true,
                                            true_label_,
                                            false_label_);
    DCHECK(!lit->IsUndetectableObject());  // There are no undetectable literals.
    if (lit->IsUndefined() || lit->IsNull() || lit->IsFalse()) {
      if (false_label_ != fall_through_) __ Branch(false_label_);
    } else if (lit->IsTrue() || lit->IsJSObject()) {
      if (true_label_ != fall_through_) __ Branch(true_label_);
    } else if (lit->IsString()) {
      if (String::cast(*lit)->length() == 0) {
        if (false_label_ != fall_through_) __ Branch(false_label_);
      } else {
        if (true_label_ != fall_through_) __ Branch(true_label_);
      }
    } else if (lit->IsSmi()) {
      if (Smi::cast(*lit)->value() == 0) {
        if (false_label_ != fall_through_) __ Branch(false_label_);
      } else {
        if (true_label_ != fall_through_) __ Branch(true_label_);
      }
    } else {
      // For simplicity we always test the accumulator register.
      __ li(result_register(), Operand(lit));
      codegen()->DoTest(this);
    }
  }
  
  
  void FullCodeGenerator::EffectContext::DropAndPlug(int count,
                                                     Register reg) const {
    DCHECK(count > 0);
    __ Drop(count);
  }
  
  
  void FullCodeGenerator::AccumulatorValueContext::DropAndPlug(
      int count,
      Register reg) const {
    DCHECK(count > 0);
    __ Drop(count);
    __ Move(result_register(), reg);
  }
  
  
  void FullCodeGenerator::StackValueContext::DropAndPlug(int count,
                                                         Register reg) const {
    DCHECK(count > 0);
    if (count > 1) __ Drop(count - 1);
    __ sw(reg, MemOperand(sp, 0));
  }
  
  
  void FullCodeGenerator::TestContext::DropAndPlug(int count,
                                                   Register reg) const {
    DCHECK(count > 0);
    // For simplicity we always test the accumulator register.
    __ Drop(count);
    __ Move(result_register(), reg);
    codegen()->PrepareForBailoutBeforeSplit(condition(), false, NULL, NULL);
    codegen()->DoTest(this);
  }
  
  
  void FullCodeGenerator::EffectContext::Plug(Label* materialize_true,
                                              Label* materialize_false) const {
    DCHECK(materialize_true == materialize_false);
    __ bind(materialize_true);
  }
  
  
  void FullCodeGenerator::AccumulatorValueContext::Plug(
      Label* materialize_true,
      Label* materialize_false) const {
    Label done;
    __ bind(materialize_true);
    __ LoadRoot(result_register(), Heap::kTrueValueRootIndex);
    __ Branch(&done);
    __ bind(materialize_false);
    __ LoadRoot(result_register(), Heap::kFalseValueRootIndex);
    __ bind(&done);
  }
  
  
  void FullCodeGenerator::StackValueContext::Plug(
      Label* materialize_true,
      Label* materialize_false) const {
    Label done;
    __ bind(materialize_true);
    __ LoadRoot(at, Heap::kTrueValueRootIndex);
    // Push the value as the following branch can clobber at in long branch mode.
    __ push(at);
    __ Branch(&done);
    __ bind(materialize_false);
    __ LoadRoot(at, Heap::kFalseValueRootIndex);
    __ push(at);
    __ bind(&done);
  }
  
  
  void FullCodeGenerator::TestContext::Plug(Label* materialize_true,
                                            Label* materialize_false) const {
    DCHECK(materialize_true == true_label_);
    DCHECK(materialize_false == false_label_);
  }
  
  
  void FullCodeGenerator::EffectContext::Plug(bool flag) const {
  }
  
  
  void FullCodeGenerator::AccumulatorValueContext::Plug(bool flag) const {
    Heap::RootListIndex value_root_index =
        flag ? Heap::kTrueValueRootIndex : Heap::kFalseValueRootIndex;
    __ LoadRoot(result_register(), value_root_index);
  }
  
  
  void FullCodeGenerator::StackValueContext::Plug(bool flag) const {
    Heap::RootListIndex value_root_index =
        flag ? Heap::kTrueValueRootIndex : Heap::kFalseValueRootIndex;
    __ LoadRoot(at, value_root_index);
    __ push(at);
  }
  
  
  void FullCodeGenerator::TestContext::Plug(bool flag) const {
    codegen()->PrepareForBailoutBeforeSplit(condition(),
                                            true,
                                            true_label_,
                                            false_label_);
    if (flag) {
      if (true_label_ != fall_through_) __ Branch(true_label_);
    } else {
      if (false_label_ != fall_through_) __ Branch(false_label_);
    }
  }
  
  
  void FullCodeGenerator::DoTest(Expression* condition,
                                 Label* if_true,
                                 Label* if_false,
                                 Label* fall_through) {
    __ mov(a0, result_register());
    Handle<Code> ic = ToBooleanStub::GetUninitialized(isolate());
    CallIC(ic, condition->test_id());
    __ mov(at, zero_reg);
    Split(ne, v0, Operand(at), if_true, if_false, fall_through);
  }
  
  
  void FullCodeGenerator::Split(Condition cc,
                                Register lhs,
                                const Operand&  rhs,
                                Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
    if (if_false == fall_through) {
      __ Branch(if_true, cc, lhs, rhs);
    } else if (if_true == fall_through) {
      __ Branch(if_false, NegateCondition(cc), lhs, rhs);
    } else {
      __ Branch(if_true, cc, lhs, rhs);
      __ Branch(if_false);
    }
  }
  
  
  MemOperand FullCodeGenerator::StackOperand(Variable* var) {
    DCHECK(var->IsStackAllocated());
    // Offset is negative because higher indexes are at lower addresses.
    int offset = -var->index() * kPointerSize;
    // Adjust by a (parameter or local) base offset.
    if (var->IsParameter()) {
      offset += (info_->scope()->num_parameters() + 1) * kPointerSize;
    } else {
      offset += JavaScriptFrameConstants::kLocal0Offset;
    }
    return MemOperand(fp, offset);
  }
  
  
  MemOperand FullCodeGenerator::VarOperand(Variable* var, Register scratch) {
    DCHECK(var->IsContextSlot() || var->IsStackAllocated());
    if (var->IsContextSlot()) {
      int context_chain_length = scope()->ContextChainLength(var->scope());
      __ LoadContext(scratch, context_chain_length);
      return ContextOperand(scratch, var->index());
    } else {
      return StackOperand(var);
    }
  }
  
  
  void FullCodeGenerator::GetVar(Register dest, Variable* var) {
    // Use destination as scratch.
    MemOperand location = VarOperand(var, dest);
    __ lw(dest, location);
  }
  
  
  void FullCodeGenerator::SetVar(Variable* var,
                                 Register src,
                                 Register scratch0,
                                 Register scratch1) {
    DCHECK(var->IsContextSlot() || var->IsStackAllocated());
    DCHECK(!scratch0.is(src));
    DCHECK(!scratch0.is(scratch1));
    DCHECK(!scratch1.is(src));
    MemOperand location = VarOperand(var, scratch0);
    __ sw(src, location);
    // Emit the write barrier code if the location is in the heap.
    if (var->IsContextSlot()) {
      __ RecordWriteContextSlot(scratch0,
                                location.offset(),
                                src,
                                scratch1,
                                kRAHasBeenSaved,
                                kDontSaveFPRegs);
    }
  }
  
  
  void FullCodeGenerator::PrepareForBailoutBeforeSplit(Expression* expr,
                                                       bool should_normalize,
                                                       Label* if_true,
                                                       Label* if_false) {
    // Only prepare for bailouts before splits if we're in a test
    // context. Otherwise, we let the Visit function deal with the
    // preparation to avoid preparing with the same AST id twice.
    if (!context()->IsTest() || !info_->IsOptimizable()) return;
  
    Label skip;
    if (should_normalize) __ Branch(&skip);
    PrepareForBailout(expr, TOS_REG);
    if (should_normalize) {
      __ LoadRoot(t0, Heap::kTrueValueRootIndex);
      Split(eq, a0, Operand(t0), if_true, if_false, NULL);
      __ bind(&skip);
    }
  }
  
  
  void FullCodeGenerator::EmitDebugCheckDeclarationContext(Variable* variable) {
    // The variable in the declaration always resides in the current function
    // context.
    DCHECK_EQ(0, scope()->ContextChainLength(variable->scope()));
    if (generate_debug_code_) {
      // Check that we're not inside a with or catch context.
      __ lw(a1, FieldMemOperand(cp, HeapObject::kMapOffset));
      __ LoadRoot(t0, Heap::kWithContextMapRootIndex);
      __ Check(ne, kDeclarationInWithContext,
          a1, Operand(t0));
      __ LoadRoot(t0, Heap::kCatchContextMapRootIndex);
      __ Check(ne, kDeclarationInCatchContext,
          a1, Operand(t0));
    }
  }
  
  
  void FullCodeGenerator::VisitVariableDeclaration(
      VariableDeclaration* declaration) {
    // 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.
    VariableProxy* proxy = declaration->proxy();
    VariableMode mode = declaration->mode();
    Variable* variable = proxy->var();
    bool hole_init = mode == LET || mode == CONST || mode == CONST_LEGACY;
    switch (variable->location()) {
      case Variable::UNALLOCATED:
        globals_->Add(variable->name(), zone());
        globals_->Add(variable->binding_needs_init()
                          ? isolate()->factory()->the_hole_value()
                          : isolate()->factory()->undefined_value(),
                      zone());
        break;
  
      case Variable::PARAMETER:
      case Variable::LOCAL:
        if (hole_init) {
          Comment cmnt(masm_, "[ VariableDeclaration");
          __ LoadRoot(t0, Heap::kTheHoleValueRootIndex);
          __ sw(t0, StackOperand(variable));
        }
        break;
  
        case Variable::CONTEXT:
        if (hole_init) {
          Comment cmnt(masm_, "[ VariableDeclaration");
          EmitDebugCheckDeclarationContext(variable);
            __ LoadRoot(at, Heap::kTheHoleValueRootIndex);
            __ sw(at, ContextOperand(cp, variable->index()));
            // No write barrier since the_hole_value is in old space.
            PrepareForBailoutForId(proxy->id(), NO_REGISTERS);
        }
        break;
  
      case Variable::LOOKUP: {
        Comment cmnt(masm_, "[ VariableDeclaration");
        __ li(a2, Operand(variable->name()));
        // Declaration nodes are always introduced in one of four modes.
        DCHECK(IsDeclaredVariableMode(mode));
        PropertyAttributes attr =
            IsImmutableVariableMode(mode) ? READ_ONLY : NONE;
        __ li(a1, Operand(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 (hole_init) {
          __ LoadRoot(a0, Heap::kTheHoleValueRootIndex);
          __ Push(cp, a2, a1, a0);
        } else {
          DCHECK(Smi::FromInt(0) == 0);
          __ mov(a0, zero_reg);  // Smi::FromInt(0) indicates no initial value.
          __ Push(cp, a2, a1, a0);
        }
        __ CallRuntime(Runtime::kDeclareLookupSlot, 4);
        break;
      }
    }
  }
  
  
  void FullCodeGenerator::VisitFunctionDeclaration(
      FunctionDeclaration* declaration) {
    VariableProxy* proxy = declaration->proxy();
    Variable* variable = proxy->var();
    switch (variable->location()) {
      case Variable::UNALLOCATED: {
        globals_->Add(variable->name(), zone());
        Handle<SharedFunctionInfo> function =
            Compiler::BuildFunctionInfo(declaration->fun(), script(), info_);
        // Check for stack-overflow exception.
        if (function.is_null()) return SetStackOverflow();
        globals_->Add(function, zone());
        break;
      }
  
      case Variable::PARAMETER:
      case Variable::LOCAL: {
        Comment cmnt(masm_, "[ FunctionDeclaration");
        VisitForAccumulatorValue(declaration->fun());
        __ sw(result_register(), StackOperand(variable));
        break;
      }
  
      case Variable::CONTEXT: {
        Comment cmnt(masm_, "[ FunctionDeclaration");
        EmitDebugCheckDeclarationContext(variable);
        VisitForAccumulatorValue(declaration->fun());
        __ sw(result_register(), ContextOperand(cp, variable->index()));
        int offset = Context::SlotOffset(variable->index());
        // We know that we have written a function, which is not a smi.
        __ RecordWriteContextSlot(cp,
                                  offset,
                                  result_register(),
                                  a2,
                                  kRAHasBeenSaved,
                                  kDontSaveFPRegs,
                                  EMIT_REMEMBERED_SET,
                                  OMIT_SMI_CHECK);
        PrepareForBailoutForId(proxy->id(), NO_REGISTERS);
        break;
      }
  
      case Variable::LOOKUP: {
        Comment cmnt(masm_, "[ FunctionDeclaration");
        __ li(a2, Operand(variable->name()));
        __ li(a1, Operand(Smi::FromInt(NONE)));
        __ Push(cp, a2, a1);
        // Push initial value for function declaration.
        VisitForStackValue(declaration->fun());
        __ CallRuntime(Runtime::kDeclareLookupSlot, 4);
        break;
      }
    }
  }
  
  
  void FullCodeGenerator::VisitModuleDeclaration(ModuleDeclaration* declaration) {
    Variable* variable = declaration->proxy()->var();
    DCHECK(variable->location() == Variable::CONTEXT);
    DCHECK(variable->interface()->IsFrozen());
  
    Comment cmnt(masm_, "[ ModuleDeclaration");
    EmitDebugCheckDeclarationContext(variable);
  
    // Load instance object.
    __ LoadContext(a1, scope_->ContextChainLength(scope_->GlobalScope()));
    __ lw(a1, ContextOperand(a1, variable->interface()->Index()));
    __ lw(a1, ContextOperand(a1, Context::EXTENSION_INDEX));
  
    // Assign it.
    __ sw(a1, ContextOperand(cp, variable->index()));
    // We know that we have written a module, which is not a smi.
    __ RecordWriteContextSlot(cp,
                              Context::SlotOffset(variable->index()),
                              a1,
                              a3,
                              kRAHasBeenSaved,
                              kDontSaveFPRegs,
                              EMIT_REMEMBERED_SET,
                              OMIT_SMI_CHECK);
    PrepareForBailoutForId(declaration->proxy()->id(), NO_REGISTERS);
  
    // Traverse into body.
    Visit(declaration->module());
  }
  
  
  void FullCodeGenerator::VisitImportDeclaration(ImportDeclaration* declaration) {
    VariableProxy* proxy = declaration->proxy();
    Variable* variable = proxy->var();
    switch (variable->location()) {
      case Variable::UNALLOCATED:
        // TODO(rossberg)
        break;
  
      case Variable::CONTEXT: {
        Comment cmnt(masm_, "[ ImportDeclaration");
        EmitDebugCheckDeclarationContext(variable);
        // TODO(rossberg)
        break;
      }
  
      case Variable::PARAMETER:
      case Variable::LOCAL:
      case Variable::LOOKUP:
        UNREACHABLE();
    }
  }
  
  
  void FullCodeGenerator::VisitExportDeclaration(ExportDeclaration* declaration) {
    // TODO(rossberg)
  }
  
  
  void FullCodeGenerator::DeclareGlobals(Handle<FixedArray> pairs) {
    // Call the runtime to declare the globals.
    // The context is the first argument.
    __ li(a1, Operand(pairs));
    __ li(a0, Operand(Smi::FromInt(DeclareGlobalsFlags())));
    __ Push(cp, a1, a0);
    __ CallRuntime(Runtime::kDeclareGlobals, 3);
    // Return value is ignored.
  }
  
  
  void FullCodeGenerator::DeclareModules(Handle<FixedArray> descriptions) {
    // Call the runtime to declare the modules.
    __ Push(descriptions);
    __ CallRuntime(Runtime::kDeclareModules, 1);
    // Return value is ignored.
  }
  
  
  void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
    Comment cmnt(masm_, "[ SwitchStatement");
    Breakable nested_statement(this, stmt);
    SetStatementPosition(stmt);
  
    // Keep the switch value on the stack until a case matches.
    VisitForStackValue(stmt->tag());
    PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
  
    ZoneList<CaseClause*>* clauses = stmt->cases();
    CaseClause* default_clause = NULL;  // Can occur anywhere in the list.
  
    Label next_test;  // Recycled for each test.
    // Compile all the tests with branches to their bodies.
    for (int i = 0; i < clauses->length(); i++) {
      CaseClause* clause = clauses->at(i);
      clause->body_target()->Unuse();
  
      // The default is not a test, but remember it as final fall through.
      if (clause->is_default()) {
        default_clause = clause;
        continue;
      }
  
      Comment cmnt(masm_, "[ Case comparison");
      __ bind(&next_test);
      next_test.Unuse();
  
      // Compile the label expression.
      VisitForAccumulatorValue(clause->label());
      __ mov(a0, result_register());  // CompareStub requires args in a0, a1.
  
      // Perform the comparison as if via '==='.
      __ lw(a1, MemOperand(sp, 0));  // Switch value.
      bool inline_smi_code = ShouldInlineSmiCase(Token::EQ_STRICT);
      JumpPatchSite patch_site(masm_);
      if (inline_smi_code) {
        Label slow_case;
        __ or_(a2, a1, a0);
        patch_site.EmitJumpIfNotSmi(a2, &slow_case);
  
        __ Branch(&next_test, ne, a1, Operand(a0));
        __ Drop(1);  // Switch value is no longer needed.
        __ Branch(clause->body_target());
  
        __ bind(&slow_case);
      }
  
      // Record position before stub call for type feedback.
      SetSourcePosition(clause->position());
      Handle<Code> ic =
          CodeFactory::CompareIC(isolate(), Token::EQ_STRICT).code();
      CallIC(ic, clause->CompareId());
      patch_site.EmitPatchInfo();
  
      Label skip;
      __ Branch(&skip);
      PrepareForBailout(clause, TOS_REG);
      __ LoadRoot(at, Heap::kTrueValueRootIndex);
      __ Branch(&next_test, ne, v0, Operand(at));
      __ Drop(1);
      __ Branch(clause->body_target());
      __ bind(&skip);
  
      __ Branch(&next_test, ne, v0, Operand(zero_reg));
      __ Drop(1);  // Switch value is no longer needed.
      __ Branch(clause->body_target());
    }
  
    // Discard the test value and jump to the default if present, otherwise to
    // the end of the statement.
    __ bind(&next_test);
    __ Drop(1);  // Switch value is no longer needed.
    if (default_clause == NULL) {
      __ Branch(nested_statement.break_label());
    } else {
      __ Branch(default_clause->body_target());
    }
  
    // Compile all the case bodies.
    for (int i = 0; i < clauses->length(); i++) {
      Comment cmnt(masm_, "[ Case body");
      CaseClause* clause = clauses->at(i);
      __ bind(clause->body_target());
      PrepareForBailoutForId(clause->EntryId(), NO_REGISTERS);
      VisitStatements(clause->statements());
    }
  
    __ bind(nested_statement.break_label());
    PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
  }
  
  
  void FullCodeGenerator::VisitForInStatement(ForInStatement* stmt) {
    Comment cmnt(masm_, "[ ForInStatement");
    FeedbackVectorSlot slot = stmt->ForInFeedbackSlot();
    SetStatementPosition(stmt);
  
    Label loop, exit;
    ForIn loop_statement(this, stmt);
    increment_loop_depth();
  
    // Get the object to enumerate over. If the object is null or undefined, skip
    // over the loop.  See ECMA-262 version 5, section 12.6.4.
    VisitForAccumulatorValue(stmt->enumerable());
    __ mov(a0, result_register());  // Result as param to InvokeBuiltin below.
    __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
    __ Branch(&exit, eq, a0, Operand(at));
    Register null_value = t1;
    __ LoadRoot(null_value, Heap::kNullValueRootIndex);
    __ Branch(&exit, eq, a0, Operand(null_value));
    PrepareForBailoutForId(stmt->PrepareId(), TOS_REG);
    __ mov(a0, v0);
    // Convert the object to a JS object.
    Label convert, done_convert;
    __ JumpIfSmi(a0, &convert);
    __ GetObjectType(a0, a1, a1);
    __ Branch(&done_convert, ge, a1, Operand(FIRST_SPEC_OBJECT_TYPE));
    __ bind(&convert);
    __ push(a0);
    __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
    __ mov(a0, v0);
    __ bind(&done_convert);
    __ push(a0);
  
    // Check for proxies.
    Label call_runtime;
    STATIC_ASSERT(FIRST_JS_PROXY_TYPE == FIRST_SPEC_OBJECT_TYPE);
    __ GetObjectType(a0, a1, a1);
    __ Branch(&call_runtime, le, a1, Operand(LAST_JS_PROXY_TYPE));
  
    // Check cache validity in generated code. This is a fast case for
    // the JSObject::IsSimpleEnum cache validity checks. If we cannot
    // guarantee cache validity, call the runtime system to check cache
    // validity or get the property names in a fixed array.
    __ CheckEnumCache(null_value, &call_runtime);
  
    // The enum cache is valid.  Load the map of the object being
    // iterated over and use the cache for the iteration.
    Label use_cache;
    __ lw(v0, FieldMemOperand(a0, HeapObject::kMapOffset));
    __ Branch(&use_cache);
  
    // Get the set of properties to enumerate.
    __ bind(&call_runtime);
    __ push(a0);  // Duplicate the enumerable object on the stack.
    __ CallRuntime(Runtime::kGetPropertyNamesFast, 1);
  
    // If we got a map from the runtime call, we can do a fast
    // modification check. Otherwise, we got a fixed array, and we have
    // to do a slow check.
    Label fixed_array;
    __ lw(a2, FieldMemOperand(v0, HeapObject::kMapOffset));
    __ LoadRoot(at, Heap::kMetaMapRootIndex);
    __ Branch(&fixed_array, ne, a2, Operand(at));
  
    // We got a map in register v0. Get the enumeration cache from it.
    Label no_descriptors;
    __ bind(&use_cache);
  
    __ EnumLength(a1, v0);
    __ Branch(&no_descriptors, eq, a1, Operand(Smi::FromInt(0)));
  
    __ LoadInstanceDescriptors(v0, a2);
    __ lw(a2, FieldMemOperand(a2, DescriptorArray::kEnumCacheOffset));
    __ lw(a2, FieldMemOperand(a2, DescriptorArray::kEnumCacheBridgeCacheOffset));
  
    // Set up the four remaining stack slots.
    __ li(a0, Operand(Smi::FromInt(0)));
    // Push map, enumeration cache, enumeration cache length (as smi) and zero.
    __ Push(v0, a2, a1, a0);
    __ jmp(&loop);
  
    __ bind(&no_descriptors);
    __ Drop(1);
    __ jmp(&exit);
  
    // We got a fixed array in register v0. Iterate through that.
    Label non_proxy;
    __ bind(&fixed_array);
  
    __ li(a1, FeedbackVector());
    __ li(a2, Operand(TypeFeedbackVector::MegamorphicSentinel(isolate())));
    __ sw(a2, FieldMemOperand(a1, FixedArray::OffsetOfElementAt(slot.ToInt())));
  
    __ li(a1, Operand(Smi::FromInt(1)));  // Smi indicates slow check
    __ lw(a2, MemOperand(sp, 0 * kPointerSize));  // Get enumerated object
    STATIC_ASSERT(FIRST_JS_PROXY_TYPE == FIRST_SPEC_OBJECT_TYPE);
    __ GetObjectType(a2, a3, a3);
    __ Branch(&non_proxy, gt, a3, Operand(LAST_JS_PROXY_TYPE));
    __ li(a1, Operand(Smi::FromInt(0)));  // Zero indicates proxy
    __ bind(&non_proxy);
    __ Push(a1, v0);  // Smi and array
    __ lw(a1, FieldMemOperand(v0, FixedArray::kLengthOffset));
    __ li(a0, Operand(Smi::FromInt(0)));
    __ Push(a1, a0);  // Fixed array length (as smi) and initial index.
  
    // Generate code for doing the condition check.
    PrepareForBailoutForId(stmt->BodyId(), NO_REGISTERS);
    __ bind(&loop);
    // Load the current count to a0, load the length to a1.
    __ lw(a0, MemOperand(sp, 0 * kPointerSize));
    __ lw(a1, MemOperand(sp, 1 * kPointerSize));
    __ Branch(loop_statement.break_label(), hs, a0, Operand(a1));
  
    // Get the current entry of the array into register a3.
    __ lw(a2, MemOperand(sp, 2 * kPointerSize));
    __ Addu(a2, a2, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
    __ sll(t0, a0, kPointerSizeLog2 - kSmiTagSize);
    __ addu(t0, a2, t0);  // Array base + scaled (smi) index.
    __ lw(a3, MemOperand(t0));  // Current entry.
  
    // Get the expected map from the stack or a smi in the
    // permanent slow case into register a2.
    __ lw(a2, MemOperand(sp, 3 * kPointerSize));
  
    // Check if the expected map still matches that of the enumerable.
    // If not, we may have to filter the key.
    Label update_each;
    __ lw(a1, MemOperand(sp, 4 * kPointerSize));
    __ lw(t0, FieldMemOperand(a1, HeapObject::kMapOffset));
    __ Branch(&update_each, eq, t0, Operand(a2));
  
    // For proxies, no filtering is done.
    // TODO(rossberg): What if only a prototype is a proxy? Not specified yet.
    DCHECK_EQ(Smi::FromInt(0), 0);
    __ Branch(&update_each, eq, a2, Operand(zero_reg));
  
    // Convert the entry to a string or (smi) 0 if it isn't a property
    // any more. If the property has been removed while iterating, we
    // just skip it.
    __ Push(a1, a3);  // Enumerable and current entry.
    __ InvokeBuiltin(Builtins::FILTER_KEY, CALL_FUNCTION);
    __ mov(a3, result_register());
    __ Branch(loop_statement.continue_label(), eq, a3, Operand(zero_reg));
  
    // Update the 'each' property or variable from the possibly filtered
    // entry in register a3.
    __ bind(&update_each);
    __ mov(result_register(), a3);
    // Perform the assignment as if via '='.
    { EffectContext context(this);
      EmitAssignment(stmt->each());
    }
  
    // Generate code for the body of the loop.
    Visit(stmt->body());
  
    // Generate code for the going to the next element by incrementing
    // the index (smi) stored on top of the stack.
    __ bind(loop_statement.continue_label());
    __ pop(a0);
    __ Addu(a0, a0, Operand(Smi::FromInt(1)));
    __ push(a0);
  
    EmitBackEdgeBookkeeping(stmt, &loop);
    __ Branch(&loop);
  
    // Remove the pointers stored on the stack.
    __ bind(loop_statement.break_label());
    __ Drop(5);
  
    // Exit and decrement the loop depth.
    PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
    __ bind(&exit);
    decrement_loop_depth();
  }
  
  
  void FullCodeGenerator::VisitForOfStatement(ForOfStatement* stmt) {
    Comment cmnt(masm_, "[ ForOfStatement");
    SetStatementPosition(stmt);
  
    Iteration loop_statement(this, stmt);
    increment_loop_depth();
  
    // var iterator = iterable[Symbol.iterator]();
    VisitForEffect(stmt->assign_iterator());
  
    // Loop entry.
    __ bind(loop_statement.continue_label());
  
    // result = iterator.next()
    VisitForEffect(stmt->next_result());
  
    // if (result.done) break;
    Label result_not_done;
    VisitForControl(stmt->result_done(),
                    loop_statement.break_label(),
                    &result_not_done,
                    &result_not_done);
    __ bind(&result_not_done);
  
    // each = result.value
    VisitForEffect(stmt->assign_each());
  
    // Generate code for the body of the loop.
    Visit(stmt->body());
  
    // Check stack before looping.
    PrepareForBailoutForId(stmt->BackEdgeId(), NO_REGISTERS);
    EmitBackEdgeBookkeeping(stmt, loop_statement.continue_label());
    __ jmp(loop_statement.continue_label());
  
    // Exit and decrement the loop depth.
    PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
    __ bind(loop_statement.break_label());
    decrement_loop_depth();
  }
  
  
  void FullCodeGenerator::EmitNewClosure(Handle<SharedFunctionInfo> info,
                                         bool pretenure) {
    // Use the fast case closure allocation code that allocates in new
    // space for nested functions that don't need literals cloning. If
    // we're running with the --always-opt or the --prepare-always-opt
    // flag, we need to use the runtime function so that the new function
    // we are creating here gets a chance to have its code optimized and
    // doesn't just get a copy of the existing unoptimized code.
    if (!FLAG_always_opt &&
        !FLAG_prepare_always_opt &&
        !pretenure &&
        scope()->is_function_scope() &&
        info->num_literals() == 0) {
      FastNewClosureStub stub(isolate(), info->strict_mode(), info->kind());
      __ li(a2, Operand(info));
      __ CallStub(&stub);
    } else {
      __ li(a0, Operand(info));
      __ LoadRoot(a1, pretenure ? Heap::kTrueValueRootIndex
                                : Heap::kFalseValueRootIndex);
      __ Push(cp, a0, a1);
      __ CallRuntime(Runtime::kNewClosure, 3);
    }
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::VisitVariableProxy(VariableProxy* expr) {
    Comment cmnt(masm_, "[ VariableProxy");
    EmitVariableLoad(expr);
  }
  
  
  void FullCodeGenerator::EmitLoadHomeObject(SuperReference* expr) {
    Comment cnmt(masm_, "[ SuperReference ");
  
    __ lw(LoadDescriptor::ReceiverRegister(),
          MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
  
    Handle<Symbol> home_object_symbol(isolate()->heap()->home_object_symbol());
    __ li(LoadDescriptor::NameRegister(), home_object_symbol);
  
    if (FLAG_vector_ics) {
      __ li(VectorLoadICDescriptor::SlotRegister(),
            Operand(SmiFromSlot(expr->HomeObjectFeedbackSlot())));
      CallLoadIC(NOT_CONTEXTUAL);
    } else {
      CallLoadIC(NOT_CONTEXTUAL, expr->HomeObjectFeedbackId());
    }
  
    Label done;
    __ Branch(&done, ne, v0, Operand(isolate()->factory()->undefined_value()));
    __ CallRuntime(Runtime::kThrowNonMethodError, 0);
    __ bind(&done);
  }
  
  
  void FullCodeGenerator::EmitLoadGlobalCheckExtensions(VariableProxy* proxy,
                                                        TypeofState typeof_state,
                                                        Label* slow) {
    Register current = cp;
    Register next = a1;
    Register temp = a2;
  
    Scope* s = scope();
    while (s != NULL) {
      if (s->num_heap_slots() > 0) {
        if (s->calls_sloppy_eval()) {
          // Check that extension is NULL.
          __ lw(temp, ContextOperand(current, Context::EXTENSION_INDEX));
          __ Branch(slow, ne, temp, Operand(zero_reg));
        }
        // Load next context in chain.
        __ lw(next, ContextOperand(current, Context::PREVIOUS_INDEX));
        // Walk the rest of the chain without clobbering cp.
        current = next;
      }
      // If no outer scope calls eval, we do not need to check more
      // context extensions.
      if (!s->outer_scope_calls_sloppy_eval() || s->is_eval_scope()) break;
      s = s->outer_scope();
    }
  
    if (s->is_eval_scope()) {
      Label loop, fast;
      if (!current.is(next)) {
        __ Move(next, current);
      }
      __ bind(&loop);
      // Terminate at native context.
      __ lw(temp, FieldMemOperand(next, HeapObject::kMapOffset));
      __ LoadRoot(t0, Heap::kNativeContextMapRootIndex);
      __ Branch(&fast, eq, temp, Operand(t0));
      // Check that extension is NULL.
      __ lw(temp, ContextOperand(next, Context::EXTENSION_INDEX));
      __ Branch(slow, ne, temp, Operand(zero_reg));
      // Load next context in chain.
      __ lw(next, ContextOperand(next, Context::PREVIOUS_INDEX));
      __ Branch(&loop);
      __ bind(&fast);
    }
  
    __ lw(LoadDescriptor::ReceiverRegister(), GlobalObjectOperand());
    __ li(LoadDescriptor::NameRegister(), Operand(proxy->var()->name()));
    if (FLAG_vector_ics) {
      __ li(VectorLoadICDescriptor::SlotRegister(),
            Operand(SmiFromSlot(proxy->VariableFeedbackSlot())));
    }
  
    ContextualMode mode = (typeof_state == INSIDE_TYPEOF)
        ? NOT_CONTEXTUAL
        : CONTEXTUAL;
    CallLoadIC(mode);
  }
  
  
  MemOperand FullCodeGenerator::ContextSlotOperandCheckExtensions(Variable* var,
                                                                  Label* slow) {
    DCHECK(var->IsContextSlot());
    Register context = cp;
    Register next = a3;
    Register temp = t0;
  
    for (Scope* s = scope(); s != var->scope(); s = s->outer_scope()) {
      if (s->num_heap_slots() > 0) {
        if (s->calls_sloppy_eval()) {
          // Check that extension is NULL.
          __ lw(temp, ContextOperand(context, Context::EXTENSION_INDEX));
          __ Branch(slow, ne, temp, Operand(zero_reg));
        }
        __ lw(next, ContextOperand(context, Context::PREVIOUS_INDEX));
        // Walk the rest of the chain without clobbering cp.
        context = next;
      }
    }
    // Check that last extension is NULL.
    __ lw(temp, ContextOperand(context, Context::EXTENSION_INDEX));
    __ Branch(slow, ne, temp, Operand(zero_reg));
  
    // This function is used only for loads, not stores, so it's safe to
    // return an cp-based operand (the write barrier cannot be allowed to
    // destroy the cp register).
    return ContextOperand(context, var->index());
  }
  
  
  void FullCodeGenerator::EmitDynamicLookupFastCase(VariableProxy* proxy,
                                                    TypeofState typeof_state,
                                                    Label* slow,
                                                    Label* done) {
    // 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.
    Variable* var = proxy->var();
    if (var->mode() == DYNAMIC_GLOBAL) {
      EmitLoadGlobalCheckExtensions(proxy, typeof_state, slow);
      __ Branch(done);
    } else if (var->mode() == DYNAMIC_LOCAL) {
      Variable* local = var->local_if_not_shadowed();
      __ lw(v0, ContextSlotOperandCheckExtensions(local, slow));
      if (local->mode() == LET || local->mode() == CONST ||
          local->mode() == CONST_LEGACY) {
        __ LoadRoot(at, Heap::kTheHoleValueRootIndex);
        __ subu(at, v0, at);  // Sub as compare: at == 0 on eq.
        if (local->mode() == CONST_LEGACY) {
          __ LoadRoot(a0, Heap::kUndefinedValueRootIndex);
          __ Movz(v0, a0, at);  // Conditional move: return Undefined if TheHole.
        } else {  // LET || CONST
          __ Branch(done, ne, at, Operand(zero_reg));
          __ li(a0, Operand(var->name()));
          __ push(a0);
          __ CallRuntime(Runtime::kThrowReferenceError, 1);
        }
      }
      __ Branch(done);
    }
  }
  
  
  void FullCodeGenerator::EmitVariableLoad(VariableProxy* proxy) {
    // Record position before possible IC call.
    SetSourcePosition(proxy->position());
    Variable* var = proxy->var();
  
    // Three cases: global variables, lookup variables, and all other types of
    // variables.
    switch (var->location()) {
      case Variable::UNALLOCATED: {
        Comment cmnt(masm_, "[ Global variable");
        __ lw(LoadDescriptor::ReceiverRegister(), GlobalObjectOperand());
        __ li(LoadDescriptor::NameRegister(), Operand(var->name()));
        if (FLAG_vector_ics) {
          __ li(VectorLoadICDescriptor::SlotRegister(),
                Operand(SmiFromSlot(proxy->VariableFeedbackSlot())));
        }
        CallLoadIC(CONTEXTUAL);
        context()->Plug(v0);
        break;
      }
  
      case Variable::PARAMETER:
      case Variable::LOCAL:
      case Variable::CONTEXT: {
        Comment cmnt(masm_, var->IsContextSlot() ? "[ Context variable"
                                                 : "[ Stack variable");
        if (var->binding_needs_init()) {
          // var->scope() may be NULL when the proxy is located in eval code and
          // refers to a potential outside binding. Currently those bindings are
          // always looked up dynamically, i.e. in that case
          //     var->location() == LOOKUP.
          // always holds.
          DCHECK(var->scope() != NULL);
  
          // Check if the binding really needs an initialization check. The check
          // can be skipped in the following situation: we have a LET or CONST
          // binding in harmony mode, both the Variable and the VariableProxy have
          // the same declaration scope (i.e. they are both in global code, in the
          // same function or in the same eval code) and the VariableProxy is in
          // the source physically located after the initializer of the variable.
          //
          // We cannot skip any initialization checks for CONST in non-harmony
          // mode because const variables may be declared but never initialized:
          //   if (false) { const x; }; var y = x;
          //
          // The condition on the declaration scopes is a conservative check for
          // nested functions that access a binding and are called before the
          // binding is initialized:
          //   function() { f(); let x = 1; function f() { x = 2; } }
          //
          bool skip_init_check;
          if (var->scope()->DeclarationScope() != scope()->DeclarationScope()) {
            skip_init_check = false;
          } else {
            // Check that we always have valid source position.
            DCHECK(var->initializer_position() != RelocInfo::kNoPosition);
            DCHECK(proxy->position() != RelocInfo::kNoPosition);
            skip_init_check = var->mode() != CONST_LEGACY &&
                var->initializer_position() < proxy->position();
          }
  
          if (!skip_init_check) {
            // Let and const need a read barrier.
            GetVar(v0, var);
            __ LoadRoot(at, Heap::kTheHoleValueRootIndex);
            __ subu(at, v0, at);  // Sub as compare: at == 0 on eq.
            if (var->mode() == LET || var->mode() == CONST) {
              // Throw a reference error when using an uninitialized let/const
              // binding in harmony mode.
              Label done;
              __ Branch(&done, ne, at, Operand(zero_reg));
              __ li(a0, Operand(var->name()));
              __ push(a0);
              __ CallRuntime(Runtime::kThrowReferenceError, 1);
              __ bind(&done);
            } else {
              // Uninitalized const bindings outside of harmony mode are unholed.
              DCHECK(var->mode() == CONST_LEGACY);
              __ LoadRoot(a0, Heap::kUndefinedValueRootIndex);
              __ Movz(v0, a0, at);  // Conditional move: Undefined if TheHole.
            }
            context()->Plug(v0);
            break;
          }
        }
        context()->Plug(var);
        break;
      }
  
      case Variable::LOOKUP: {
        Comment cmnt(masm_, "[ Lookup variable");
        Label done, slow;
        // Generate code for loading from variables potentially shadowed
        // by eval-introduced variables.
        EmitDynamicLookupFastCase(proxy, NOT_INSIDE_TYPEOF, &slow, &done);
        __ bind(&slow);
        __ li(a1, Operand(var->name()));
        __ Push(cp, a1);  // Context and name.
        __ CallRuntime(Runtime::kLoadLookupSlot, 2);
        __ bind(&done);
        context()->Plug(v0);
      }
    }
  }
  
  
  void FullCodeGenerator::VisitRegExpLiteral(RegExpLiteral* expr) {
    Comment cmnt(masm_, "[ RegExpLiteral");
    Label materialized;
    // Registers will be used as follows:
    // t1 = materialized value (RegExp literal)
    // t0 = JS function, literals array
    // a3 = literal index
    // a2 = RegExp pattern
    // a1 = RegExp flags
    // a0 = RegExp literal clone
    __ lw(a0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
    __ lw(t0, FieldMemOperand(a0, JSFunction::kLiteralsOffset));
    int literal_offset =
        FixedArray::kHeaderSize + expr->literal_index() * kPointerSize;
    __ lw(t1, FieldMemOperand(t0, literal_offset));
    __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
    __ Branch(&materialized, ne, t1, Operand(at));
  
    // Create regexp literal using runtime function.
    // Result will be in v0.
    __ li(a3, Operand(Smi::FromInt(expr->literal_index())));
    __ li(a2, Operand(expr->pattern()));
    __ li(a1, Operand(expr->flags()));
    __ Push(t0, a3, a2, a1);
    __ CallRuntime(Runtime::kMaterializeRegExpLiteral, 4);
    __ mov(t1, v0);
  
    __ bind(&materialized);
    int size = JSRegExp::kSize + JSRegExp::kInObjectFieldCount * kPointerSize;
    Label allocated, runtime_allocate;
    __ Allocate(size, v0, a2, a3, &runtime_allocate, TAG_OBJECT);
    __ jmp(&allocated);
  
    __ bind(&runtime_allocate);
    __ li(a0, Operand(Smi::FromInt(size)));
    __ Push(t1, a0);
    __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
    __ pop(t1);
  
    __ bind(&allocated);
  
    // After this, registers are used as follows:
    // v0: Newly allocated regexp.
    // t1: Materialized regexp.
    // a2: temp.
    __ CopyFields(v0, t1, a2.bit(), size / kPointerSize);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitAccessor(Expression* expression) {
    if (expression == NULL) {
      __ LoadRoot(a1, Heap::kNullValueRootIndex);
      __ push(a1);
    } else {
      VisitForStackValue(expression);
    }
  }
  
  
  void FullCodeGenerator::VisitObjectLiteral(ObjectLiteral* expr) {
    Comment cmnt(masm_, "[ ObjectLiteral");
  
    expr->BuildConstantProperties(isolate());
    Handle<FixedArray> constant_properties = expr->constant_properties();
    __ lw(a3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
    __ lw(a3, FieldMemOperand(a3, JSFunction::kLiteralsOffset));
    __ li(a2, Operand(Smi::FromInt(expr->literal_index())));
    __ li(a1, Operand(constant_properties));
    int flags = expr->fast_elements()
        ? ObjectLiteral::kFastElements
        : ObjectLiteral::kNoFlags;
    flags |= expr->has_function()
        ? ObjectLiteral::kHasFunction
        : ObjectLiteral::kNoFlags;
    __ li(a0, Operand(Smi::FromInt(flags)));
    int properties_count = constant_properties->length() / 2;
    if (expr->may_store_doubles() || expr->depth() > 1 ||
        masm()->serializer_enabled() || flags != ObjectLiteral::kFastElements ||
        properties_count > FastCloneShallowObjectStub::kMaximumClonedProperties) {
      __ Push(a3, a2, a1, a0);
      __ CallRuntime(Runtime::kCreateObjectLiteral, 4);
    } else {
      FastCloneShallowObjectStub stub(isolate(), properties_count);
      __ CallStub(&stub);
    }
  
    // If result_saved is true the result is on top of the stack.  If
    // result_saved is false the result is in v0.
    bool result_saved = false;
  
    // Mark all computed expressions that are bound to a key that
    // is shadowed by a later occurrence of the same key. For the
    // marked expressions, no store code is emitted.
    expr->CalculateEmitStore(zone());
  
    AccessorTable accessor_table(zone());
    for (int i = 0; i < expr->properties()->length(); i++) {
      ObjectLiteral::Property* property = expr->properties()->at(i);
      if (property->IsCompileTimeValue()) continue;
  
      Literal* key = property->key();
      Expression* value = property->value();
      if (!result_saved) {
        __ push(v0);  // Save result on stack.
        result_saved = true;
      }
      switch (property->kind()) {
        case ObjectLiteral::Property::CONSTANT:
          UNREACHABLE();
        case ObjectLiteral::Property::MATERIALIZED_LITERAL:
          DCHECK(!CompileTimeValue::IsCompileTimeValue(property->value()));
          // Fall through.
        case ObjectLiteral::Property::COMPUTED:
          if (key->value()->IsInternalizedString()) {
            if (property->emit_store()) {
              VisitForAccumulatorValue(value);
              __ mov(StoreDescriptor::ValueRegister(), result_register());
              DCHECK(StoreDescriptor::ValueRegister().is(a0));
              __ li(StoreDescriptor::NameRegister(), Operand(key->value()));
              __ lw(StoreDescriptor::ReceiverRegister(), MemOperand(sp));
              CallStoreIC(key->LiteralFeedbackId());
              PrepareForBailoutForId(key->id(), NO_REGISTERS);
            } else {
              VisitForEffect(value);
            }
            break;
          }
          // Duplicate receiver on stack.
          __ lw(a0, MemOperand(sp));
          __ push(a0);
          VisitForStackValue(key);
          VisitForStackValue(value);
          if (property->emit_store()) {
            __ li(a0, Operand(Smi::FromInt(SLOPPY)));  // PropertyAttributes.
            __ push(a0);
            __ CallRuntime(Runtime::kSetProperty, 4);
          } else {
            __ Drop(3);
          }
          break;
        case ObjectLiteral::Property::PROTOTYPE:
          // Duplicate receiver on stack.
          __ lw(a0, MemOperand(sp));
          __ push(a0);
          VisitForStackValue(value);
          if (property->emit_store()) {
            __ CallRuntime(Runtime::kSetPrototype, 2);
          } else {
            __ Drop(2);
          }
          break;
        case ObjectLiteral::Property::GETTER:
          accessor_table.lookup(key)->second->getter = value;
          break;
        case ObjectLiteral::Property::SETTER:
          accessor_table.lookup(key)->second->setter = value;
          break;
      }
    }
  
    // Emit code to define accessors, using only a single call to the runtime for
    // each pair of corresponding getters and setters.
    for (AccessorTable::Iterator it = accessor_table.begin();
         it != accessor_table.end();
         ++it) {
      __ lw(a0, MemOperand(sp));  // Duplicate receiver.
      __ push(a0);
      VisitForStackValue(it->first);
      EmitAccessor(it->second->getter);
      EmitAccessor(it->second->setter);
      __ li(a0, Operand(Smi::FromInt(NONE)));
      __ push(a0);
      __ CallRuntime(Runtime::kDefineAccessorPropertyUnchecked, 5);
    }
  
    if (expr->has_function()) {
      DCHECK(result_saved);
      __ lw(a0, MemOperand(sp));
      __ push(a0);
      __ CallRuntime(Runtime::kToFastProperties, 1);
    }
  
    if (result_saved) {
      context()->PlugTOS();
    } else {
      context()->Plug(v0);
    }
  }
  
  
  void FullCodeGenerator::VisitArrayLiteral(ArrayLiteral* expr) {
    Comment cmnt(masm_, "[ ArrayLiteral");
  
    expr->BuildConstantElements(isolate());
    int flags = expr->depth() == 1
        ? ArrayLiteral::kShallowElements
        : ArrayLiteral::kNoFlags;
  
    ZoneList<Expression*>* subexprs = expr->values();
    int length = subexprs->length();
  
    Handle<FixedArray> constant_elements = expr->constant_elements();
    DCHECK_EQ(2, constant_elements->length());
    ElementsKind constant_elements_kind =
        static_cast<ElementsKind>(Smi::cast(constant_elements->get(0))->value());
    bool has_fast_elements =
        IsFastObjectElementsKind(constant_elements_kind);
    Handle<FixedArrayBase> constant_elements_values(
        FixedArrayBase::cast(constant_elements->get(1)));
  
    AllocationSiteMode allocation_site_mode = TRACK_ALLOCATION_SITE;
    if (has_fast_elements && !FLAG_allocation_site_pretenuring) {
      // If the only customer of allocation sites is transitioning, then
      // we can turn it off if we don't have anywhere else to transition to.
      allocation_site_mode = DONT_TRACK_ALLOCATION_SITE;
    }
  
    __ mov(a0, result_register());
    __ lw(a3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
    __ lw(a3, FieldMemOperand(a3, JSFunction::kLiteralsOffset));
    __ li(a2, Operand(Smi::FromInt(expr->literal_index())));
    __ li(a1, Operand(constant_elements));
    if (expr->depth() > 1 || length > JSObject::kInitialMaxFastElementArray) {
      __ li(a0, Operand(Smi::FromInt(flags)));
      __ Push(a3, a2, a1, a0);
      __ CallRuntime(Runtime::kCreateArrayLiteral, 4);
    } else {
      FastCloneShallowArrayStub stub(isolate(), allocation_site_mode);
      __ CallStub(&stub);
    }
  
    bool result_saved = false;  // Is the result saved to the stack?
  
    // Emit code to evaluate all the non-constant subexpressions and to store
    // them into the newly cloned array.
    for (int i = 0; i < length; i++) {
      Expression* subexpr = subexprs->at(i);
      // If the subexpression is a literal or a simple materialized literal it
      // is already set in the cloned array.
      if (CompileTimeValue::IsCompileTimeValue(subexpr)) continue;
  
      if (!result_saved) {
        __ push(v0);  // array literal
        __ Push(Smi::FromInt(expr->literal_index()));
        result_saved = true;
      }
  
      VisitForAccumulatorValue(subexpr);
  
      if (IsFastObjectElementsKind(constant_elements_kind)) {
        int offset = FixedArray::kHeaderSize + (i * kPointerSize);
        __ lw(t2, MemOperand(sp, kPointerSize));  // Copy of array literal.
        __ lw(a1, FieldMemOperand(t2, JSObject::kElementsOffset));
        __ sw(result_register(), FieldMemOperand(a1, offset));
        // Update the write barrier for the array store.
        __ RecordWriteField(a1, offset, result_register(), a2,
                            kRAHasBeenSaved, kDontSaveFPRegs,
                            EMIT_REMEMBERED_SET, INLINE_SMI_CHECK);
      } else {
        __ li(a3, Operand(Smi::FromInt(i)));
        __ mov(a0, result_register());
        StoreArrayLiteralElementStub stub(isolate());
        __ CallStub(&stub);
      }
  
      PrepareForBailoutForId(expr->GetIdForElement(i), NO_REGISTERS);
    }
    if (result_saved) {
      __ Pop();  // literal index
      context()->PlugTOS();
    } else {
      context()->Plug(v0);
    }
  }
  
  
  void FullCodeGenerator::VisitAssignment(Assignment* expr) {
    DCHECK(expr->target()->IsValidReferenceExpression());
  
    Comment cmnt(masm_, "[ Assignment");
  
    Property* property = expr->target()->AsProperty();
    LhsKind assign_type = GetAssignType(property);
  
    // Evaluate LHS expression.
    switch (assign_type) {
      case VARIABLE:
        // Nothing to do here.
        break;
      case NAMED_PROPERTY:
        if (expr->is_compound()) {
          // We need the receiver both on the stack and in the register.
          VisitForStackValue(property->obj());
          __ lw(LoadDescriptor::ReceiverRegister(), MemOperand(sp, 0));
        } else {
          VisitForStackValue(property->obj());
        }
        break;
      case NAMED_SUPER_PROPERTY:
        VisitForStackValue(property->obj()->AsSuperReference()->this_var());
        EmitLoadHomeObject(property->obj()->AsSuperReference());
        __ Push(result_register());
        if (expr->is_compound()) {
          const Register scratch = a1;
          __ lw(scratch, MemOperand(sp, kPointerSize));
          __ Push(scratch, result_register());
        }
        break;
      case KEYED_SUPER_PROPERTY: {
        const Register scratch = a1;
        VisitForStackValue(property->obj()->AsSuperReference()->this_var());
        EmitLoadHomeObject(property->obj()->AsSuperReference());
        __ Move(scratch, result_register());
        VisitForAccumulatorValue(property->key());
        __ Push(scratch, result_register());
        if (expr->is_compound()) {
          const Register scratch1 = t0;
          __ lw(scratch1, MemOperand(sp, 2 * kPointerSize));
          __ Push(scratch1, scratch, result_register());
        }
        break;
      }
      case KEYED_PROPERTY:
        // We need the key and receiver on both the stack and in v0 and a1.
        if (expr->is_compound()) {
          VisitForStackValue(property->obj());
          VisitForStackValue(property->key());
          __ lw(LoadDescriptor::ReceiverRegister(),
                MemOperand(sp, 1 * kPointerSize));
          __ lw(LoadDescriptor::NameRegister(), MemOperand(sp, 0));
        } else {
          VisitForStackValue(property->obj());
          VisitForStackValue(property->key());
        }
        break;
    }
  
    // For compound assignments we need another deoptimization point after the
    // variable/property load.
    if (expr->is_compound()) {
      { AccumulatorValueContext context(this);
        switch (assign_type) {
          case VARIABLE:
            EmitVariableLoad(expr->target()->AsVariableProxy());
            PrepareForBailout(expr->target(), TOS_REG);
            break;
          case NAMED_PROPERTY:
            EmitNamedPropertyLoad(property);
            PrepareForBailoutForId(property->LoadId(), TOS_REG);
            break;
          case NAMED_SUPER_PROPERTY:
            EmitNamedSuperPropertyLoad(property);
            PrepareForBailoutForId(property->LoadId(), TOS_REG);
            break;
          case KEYED_SUPER_PROPERTY:
            EmitKeyedSuperPropertyLoad(property);
            PrepareForBailoutForId(property->LoadId(), TOS_REG);
            break;
          case KEYED_PROPERTY:
            EmitKeyedPropertyLoad(property);
            PrepareForBailoutForId(property->LoadId(), TOS_REG);
            break;
        }
      }
  
      Token::Value op = expr->binary_op();
      __ push(v0);  // Left operand goes on the stack.
      VisitForAccumulatorValue(expr->value());
  
      OverwriteMode mode = expr->value()->ResultOverwriteAllowed()
          ? OVERWRITE_RIGHT
          : NO_OVERWRITE;
      SetSourcePosition(expr->position() + 1);
      AccumulatorValueContext context(this);
      if (ShouldInlineSmiCase(op)) {
        EmitInlineSmiBinaryOp(expr->binary_operation(),
                              op,
                              mode,
                              expr->target(),
                              expr->value());
      } else {
        EmitBinaryOp(expr->binary_operation(), op, mode);
      }
  
      // Deoptimization point in case the binary operation may have side effects.
      PrepareForBailout(expr->binary_operation(), TOS_REG);
    } else {
      VisitForAccumulatorValue(expr->value());
    }
  
    // Record source position before possible IC call.
    SetSourcePosition(expr->position());
  
    // Store the value.
    switch (assign_type) {
      case VARIABLE:
        EmitVariableAssignment(expr->target()->AsVariableProxy()->var(),
                               expr->op());
        PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
        context()->Plug(v0);
        break;
      case NAMED_PROPERTY:
        EmitNamedPropertyAssignment(expr);
        break;
      case NAMED_SUPER_PROPERTY:
        EmitNamedSuperPropertyStore(property);
        context()->Plug(v0);
        break;
      case KEYED_SUPER_PROPERTY:
        EmitKeyedSuperPropertyStore(property);
        context()->Plug(v0);
        break;
      case KEYED_PROPERTY:
        EmitKeyedPropertyAssignment(expr);
        break;
    }
  }
  
  
  void FullCodeGenerator::VisitYield(Yield* expr) {
    Comment cmnt(masm_, "[ Yield");
    // Evaluate yielded value first; the initial iterator definition depends on
    // this.  It stays on the stack while we update the iterator.
    VisitForStackValue(expr->expression());
  
    switch (expr->yield_kind()) {
      case Yield::kSuspend:
        // Pop value from top-of-stack slot; box result into result register.
        EmitCreateIteratorResult(false);
        __ push(result_register());
        // Fall through.
      case Yield::kInitial: {
        Label suspend, continuation, post_runtime, resume;
  
        __ jmp(&suspend);
  
        __ bind(&continuation);
        __ jmp(&resume);
  
        __ bind(&suspend);
        VisitForAccumulatorValue(expr->generator_object());
        DCHECK(continuation.pos() > 0 && Smi::IsValid(continuation.pos()));
        __ li(a1, Operand(Smi::FromInt(continuation.pos())));
        __ sw(a1, FieldMemOperand(v0, JSGeneratorObject::kContinuationOffset));
        __ sw(cp, FieldMemOperand(v0, JSGeneratorObject::kContextOffset));
        __ mov(a1, cp);
        __ RecordWriteField(v0, JSGeneratorObject::kContextOffset, a1, a2,
                            kRAHasBeenSaved, kDontSaveFPRegs);
        __ Addu(a1, fp, Operand(StandardFrameConstants::kExpressionsOffset));
        __ Branch(&post_runtime, eq, sp, Operand(a1));
        __ push(v0);  // generator object
        __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
        __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
        __ bind(&post_runtime);
        __ pop(result_register());
        EmitReturnSequence();
  
        __ bind(&resume);
        context()->Plug(result_register());
        break;
      }
  
      case Yield::kFinal: {
        VisitForAccumulatorValue(expr->generator_object());
        __ li(a1, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorClosed)));
        __ sw(a1, FieldMemOperand(result_register(),
                                  JSGeneratorObject::kContinuationOffset));
        // Pop value from top-of-stack slot, box result into result register.
        EmitCreateIteratorResult(true);
        EmitUnwindBeforeReturn();
        EmitReturnSequence();
        break;
      }
  
      case Yield::kDelegating: {
        VisitForStackValue(expr->generator_object());
  
        // Initial stack layout is as follows:
        // [sp + 1 * kPointerSize] iter
        // [sp + 0 * kPointerSize] g
  
        Label l_catch, l_try, l_suspend, l_continuation, l_resume;
        Label l_next, l_call;
        Register load_receiver = LoadDescriptor::ReceiverRegister();
        Register load_name = LoadDescriptor::NameRegister();
  
        // Initial send value is undefined.
        __ LoadRoot(a0, Heap::kUndefinedValueRootIndex);
        __ Branch(&l_next);
  
        // catch (e) { receiver = iter; f = 'throw'; arg = e; goto l_call; }
        __ bind(&l_catch);
        __ mov(a0, v0);
        handler_table()->set(expr->index(), Smi::FromInt(l_catch.pos()));
        __ LoadRoot(load_name, Heap::kthrow_stringRootIndex);  // "throw"
        __ lw(a3, MemOperand(sp, 1 * kPointerSize));           // iter
        __ Push(load_name, a3, a0);                     // "throw", iter, except
        __ jmp(&l_call);
  
        // try { received = %yield result }
        // Shuffle the received result above a try handler and yield it without
        // re-boxing.
        __ bind(&l_try);
        __ pop(a0);                                        // result
        __ PushTryHandler(StackHandler::CATCH, expr->index());
        const int handler_size = StackHandlerConstants::kSize;
        __ push(a0);                                       // result
        __ jmp(&l_suspend);
        __ bind(&l_continuation);
        __ mov(a0, v0);
        __ jmp(&l_resume);
        __ bind(&l_suspend);
        const int generator_object_depth = kPointerSize + handler_size;
        __ lw(a0, MemOperand(sp, generator_object_depth));
        __ push(a0);                                       // g
        DCHECK(l_continuation.pos() > 0 && Smi::IsValid(l_continuation.pos()));
        __ li(a1, Operand(Smi::FromInt(l_continuation.pos())));
        __ sw(a1, FieldMemOperand(a0, JSGeneratorObject::kContinuationOffset));
        __ sw(cp, FieldMemOperand(a0, JSGeneratorObject::kContextOffset));
        __ mov(a1, cp);
        __ RecordWriteField(a0, JSGeneratorObject::kContextOffset, a1, a2,
                            kRAHasBeenSaved, kDontSaveFPRegs);
        __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
        __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
        __ pop(v0);                                      // result
        EmitReturnSequence();
        __ mov(a0, v0);
        __ bind(&l_resume);                              // received in a0
        __ PopTryHandler();
  
        // receiver = iter; f = 'next'; arg = received;
        __ bind(&l_next);
  
        __ LoadRoot(load_name, Heap::knext_stringRootIndex);  // "next"
        __ lw(a3, MemOperand(sp, 1 * kPointerSize));          // iter
        __ Push(load_name, a3, a0);                      // "next", iter, received
  
        // result = receiver[f](arg);
        __ bind(&l_call);
        __ lw(load_receiver, MemOperand(sp, kPointerSize));
        __ lw(load_name, MemOperand(sp, 2 * kPointerSize));
        if (FLAG_vector_ics) {
          __ li(VectorLoadICDescriptor::SlotRegister(),
                Operand(SmiFromSlot(expr->KeyedLoadFeedbackSlot())));
        }
        Handle<Code> ic = CodeFactory::KeyedLoadIC(isolate()).code();
        CallIC(ic, TypeFeedbackId::None());
        __ mov(a0, v0);
        __ mov(a1, a0);
        __ sw(a1, MemOperand(sp, 2 * kPointerSize));
        CallFunctionStub stub(isolate(), 1, CALL_AS_METHOD);
        __ CallStub(&stub);
  
        __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
        __ Drop(1);  // The function is still on the stack; drop it.
  
        // if (!result.done) goto l_try;
        __ Move(load_receiver, v0);
  
        __ push(load_receiver);                               // save result
        __ LoadRoot(load_name, Heap::kdone_stringRootIndex);  // "done"
        if (FLAG_vector_ics) {
          __ li(VectorLoadICDescriptor::SlotRegister(),
                Operand(SmiFromSlot(expr->DoneFeedbackSlot())));
        }
        CallLoadIC(NOT_CONTEXTUAL);                           // v0=result.done
        __ mov(a0, v0);
        Handle<Code> bool_ic = ToBooleanStub::GetUninitialized(isolate());
        CallIC(bool_ic);
        __ Branch(&l_try, eq, v0, Operand(zero_reg));
  
        // result.value
        __ pop(load_receiver);                                 // result
        __ LoadRoot(load_name, Heap::kvalue_stringRootIndex);  // "value"
        if (FLAG_vector_ics) {
          __ li(VectorLoadICDescriptor::SlotRegister(),
                Operand(SmiFromSlot(expr->ValueFeedbackSlot())));
        }
        CallLoadIC(NOT_CONTEXTUAL);                            // v0=result.value
        context()->DropAndPlug(2, v0);                         // drop iter and g
        break;
      }
    }
  }
  
  
  void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
      Expression *value,
      JSGeneratorObject::ResumeMode resume_mode) {
    // The value stays in a0, and is ultimately read by the resumed generator, as
    // if CallRuntime(Runtime::kSuspendJSGeneratorObject) returned it. Or it
    // is read to throw the value when the resumed generator is already closed.
    // a1 will hold the generator object until the activation has been resumed.
    VisitForStackValue(generator);
    VisitForAccumulatorValue(value);
    __ pop(a1);
  
    // Check generator state.
    Label wrong_state, closed_state, done;
    __ lw(a3, FieldMemOperand(a1, JSGeneratorObject::kContinuationOffset));
    STATIC_ASSERT(JSGeneratorObject::kGeneratorExecuting < 0);
    STATIC_ASSERT(JSGeneratorObject::kGeneratorClosed == 0);
    __ Branch(&closed_state, eq, a3, Operand(zero_reg));
    __ Branch(&wrong_state, lt, a3, Operand(zero_reg));
  
    // Load suspended function and context.
    __ lw(cp, FieldMemOperand(a1, JSGeneratorObject::kContextOffset));
    __ lw(t0, FieldMemOperand(a1, JSGeneratorObject::kFunctionOffset));
  
    // Load receiver and store as the first argument.
    __ lw(a2, FieldMemOperand(a1, JSGeneratorObject::kReceiverOffset));
    __ push(a2);
  
    // Push holes for the rest of the arguments to the generator function.
    __ lw(a3, FieldMemOperand(t0, JSFunction::kSharedFunctionInfoOffset));
    __ lw(a3,
          FieldMemOperand(a3, SharedFunctionInfo::kFormalParameterCountOffset));
    __ LoadRoot(a2, Heap::kTheHoleValueRootIndex);
    Label push_argument_holes, push_frame;
    __ bind(&push_argument_holes);
    __ Subu(a3, a3, Operand(Smi::FromInt(1)));
    __ Branch(&push_frame, lt, a3, Operand(zero_reg));
    __ push(a2);
    __ jmp(&push_argument_holes);
  
    // Enter a new JavaScript frame, and initialize its slots as they were when
    // the generator was suspended.
    Label resume_frame;
    __ bind(&push_frame);
    __ Call(&resume_frame);
    __ jmp(&done);
    __ bind(&resume_frame);
    // ra = return address.
    // fp = caller's frame pointer.
    // cp = callee's context,
    // t0 = callee's JS function.
    __ Push(ra, fp, cp, t0);
    // Adjust FP to point to saved FP.
    __ Addu(fp, sp, 2 * kPointerSize);
  
    // Load the operand stack size.
    __ lw(a3, FieldMemOperand(a1, JSGeneratorObject::kOperandStackOffset));
    __ lw(a3, FieldMemOperand(a3, FixedArray::kLengthOffset));
    __ SmiUntag(a3);
  
    // If we are sending a value and there is no operand stack, we can jump back
    // in directly.
    if (resume_mode == JSGeneratorObject::NEXT) {
      Label slow_resume;
      __ Branch(&slow_resume, ne, a3, Operand(zero_reg));
      __ lw(a3, FieldMemOperand(t0, JSFunction::kCodeEntryOffset));
      __ lw(a2, FieldMemOperand(a1, JSGeneratorObject::kContinuationOffset));
      __ SmiUntag(a2);
      __ Addu(a3, a3, Operand(a2));
      __ li(a2, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorExecuting)));
      __ sw(a2, FieldMemOperand(a1, JSGeneratorObject::kContinuationOffset));
      __ Jump(a3);
      __ bind(&slow_resume);
    }
  
    // Otherwise, we push holes for the operand stack and call the runtime to fix
    // up the stack and the handlers.
    Label push_operand_holes, call_resume;
    __ bind(&push_operand_holes);
    __ Subu(a3, a3, Operand(1));
    __ Branch(&call_resume, lt, a3, Operand(zero_reg));
    __ push(a2);
    __ Branch(&push_operand_holes);
    __ bind(&call_resume);
    DCHECK(!result_register().is(a1));
    __ Push(a1, result_register());
    __ Push(Smi::FromInt(resume_mode));
    __ CallRuntime(Runtime::kResumeJSGeneratorObject, 3);
    // Not reached: the runtime call returns elsewhere.
    __ stop("not-reached");
  
    // Reach here when generator is closed.
    __ bind(&closed_state);
    if (resume_mode == JSGeneratorObject::NEXT) {
      // Return completed iterator result when generator is closed.
      __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
      __ push(a2);
      // Pop value from top-of-stack slot; box result into result register.
      EmitCreateIteratorResult(true);
    } else {
      // Throw the provided value.
      __ push(a0);
      __ CallRuntime(Runtime::kThrow, 1);
    }
    __ jmp(&done);
  
    // Throw error if we attempt to operate on a running generator.
    __ bind(&wrong_state);
    __ push(a1);
    __ CallRuntime(Runtime::kThrowGeneratorStateError, 1);
  
    __ bind(&done);
    context()->Plug(result_register());
  }
  
  
  void FullCodeGenerator::EmitCreateIteratorResult(bool done) {
    Label gc_required;
    Label allocated;
  
    Handle<Map> map(isolate()->native_context()->iterator_result_map());
  
    __ Allocate(map->instance_size(), v0, a2, a3, &gc_required, TAG_OBJECT);
    __ jmp(&allocated);
  
    __ bind(&gc_required);
    __ Push(Smi::FromInt(map->instance_size()));
    __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
    __ lw(context_register(),
          MemOperand(fp, StandardFrameConstants::kContextOffset));
  
    __ bind(&allocated);
    __ li(a1, Operand(map));
    __ pop(a2);
    __ li(a3, Operand(isolate()->factory()->ToBoolean(done)));
    __ li(t0, Operand(isolate()->factory()->empty_fixed_array()));
    DCHECK_EQ(map->instance_size(), 5 * kPointerSize);
    __ sw(a1, FieldMemOperand(v0, HeapObject::kMapOffset));
    __ sw(t0, FieldMemOperand(v0, JSObject::kPropertiesOffset));
    __ sw(t0, FieldMemOperand(v0, JSObject::kElementsOffset));
    __ sw(a2,
          FieldMemOperand(v0, JSGeneratorObject::kResultValuePropertyOffset));
    __ sw(a3,
          FieldMemOperand(v0, JSGeneratorObject::kResultDonePropertyOffset));
  
    // Only the value field needs a write barrier, as the other values are in the
    // root set.
    __ RecordWriteField(v0, JSGeneratorObject::kResultValuePropertyOffset,
                        a2, a3, kRAHasBeenSaved, kDontSaveFPRegs);
  }
  
  
  void FullCodeGenerator::EmitNamedPropertyLoad(Property* prop) {
    SetSourcePosition(prop->position());
    Literal* key = prop->key()->AsLiteral();
    DCHECK(!prop->IsSuperAccess());
  
    __ li(LoadDescriptor::NameRegister(), Operand(key->value()));
    if (FLAG_vector_ics) {
      __ li(VectorLoadICDescriptor::SlotRegister(),
            Operand(SmiFromSlot(prop->PropertyFeedbackSlot())));
      CallLoadIC(NOT_CONTEXTUAL);
    } else {
      CallLoadIC(NOT_CONTEXTUAL, prop->PropertyFeedbackId());
    }
  }
  
  
  void FullCodeGenerator::EmitNamedSuperPropertyLoad(Property* prop) {
    // Stack: receiver, home_object.
    SetSourcePosition(prop->position());
    Literal* key = prop->key()->AsLiteral();
    DCHECK(!key->value()->IsSmi());
    DCHECK(prop->IsSuperAccess());
  
    __ Push(key->value());
    __ CallRuntime(Runtime::kLoadFromSuper, 3);
  }
  
  
  void FullCodeGenerator::EmitKeyedPropertyLoad(Property* prop) {
    SetSourcePosition(prop->position());
    Handle<Code> ic = CodeFactory::KeyedLoadIC(isolate()).code();
    if (FLAG_vector_ics) {
      __ li(VectorLoadICDescriptor::SlotRegister(),
            Operand(SmiFromSlot(prop->PropertyFeedbackSlot())));
      CallIC(ic);
    } else {
      CallIC(ic, prop->PropertyFeedbackId());
    }
  }
  
  
  void FullCodeGenerator::EmitKeyedSuperPropertyLoad(Property* prop) {
    // Stack: receiver, home_object, key.
    SetSourcePosition(prop->position());
  
    __ CallRuntime(Runtime::kLoadKeyedFromSuper, 3);
  }
  
  
  void FullCodeGenerator::EmitInlineSmiBinaryOp(BinaryOperation* expr,
                                                Token::Value op,
                                                OverwriteMode mode,
                                                Expression* left_expr,
                                                Expression* right_expr) {
    Label done, smi_case, stub_call;
  
    Register scratch1 = a2;
    Register scratch2 = a3;
  
    // Get the arguments.
    Register left = a1;
    Register right = a0;
    __ pop(left);
    __ mov(a0, result_register());
  
    // Perform combined smi check on both operands.
    __ Or(scratch1, left, Operand(right));
    STATIC_ASSERT(kSmiTag == 0);
    JumpPatchSite patch_site(masm_);
    patch_site.EmitJumpIfSmi(scratch1, &smi_case);
  
    __ bind(&stub_call);
    Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), op, mode).code();
    CallIC(code, expr->BinaryOperationFeedbackId());
    patch_site.EmitPatchInfo();
    __ jmp(&done);
  
    __ bind(&smi_case);
    // Smi case. This code works the same way as the smi-smi case in the type
    // recording binary operation stub, see
    switch (op) {
      case Token::SAR:
        __ GetLeastBitsFromSmi(scratch1, right, 5);
        __ srav(right, left, scratch1);
        __ And(v0, right, Operand(~kSmiTagMask));
        break;
      case Token::SHL: {
        __ SmiUntag(scratch1, left);
        __ GetLeastBitsFromSmi(scratch2, right, 5);
        __ sllv(scratch1, scratch1, scratch2);
        __ Addu(scratch2, scratch1, Operand(0x40000000));
        __ Branch(&stub_call, lt, scratch2, Operand(zero_reg));
        __ SmiTag(v0, scratch1);
        break;
      }
      case Token::SHR: {
        __ SmiUntag(scratch1, left);
        __ GetLeastBitsFromSmi(scratch2, right, 5);
        __ srlv(scratch1, scratch1, scratch2);
        __ And(scratch2, scratch1, 0xc0000000);
        __ Branch(&stub_call, ne, scratch2, Operand(zero_reg));
        __ SmiTag(v0, scratch1);
        break;
      }
      case Token::ADD:
        __ AdduAndCheckForOverflow(v0, left, right, scratch1);
        __ BranchOnOverflow(&stub_call, scratch1);
        break;
      case Token::SUB:
        __ SubuAndCheckForOverflow(v0, left, right, scratch1);
        __ BranchOnOverflow(&stub_call, scratch1);
        break;
      case Token::MUL: {
        __ SmiUntag(scratch1, right);
        __ Mul(scratch2, v0, left, scratch1);
        __ sra(scratch1, v0, 31);
        __ Branch(&stub_call, ne, scratch1, Operand(scratch2));
        __ Branch(&done, ne, v0, Operand(zero_reg));
        __ Addu(scratch2, right, left);
        __ Branch(&stub_call, lt, scratch2, Operand(zero_reg));
        DCHECK(Smi::FromInt(0) == 0);
        __ mov(v0, zero_reg);
        break;
      }
      case Token::BIT_OR:
        __ Or(v0, left, Operand(right));
        break;
      case Token::BIT_AND:
        __ And(v0, left, Operand(right));
        break;
      case Token::BIT_XOR:
        __ Xor(v0, left, Operand(right));
        break;
      default:
        UNREACHABLE();
    }
  
    __ bind(&done);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitBinaryOp(BinaryOperation* expr,
                                       Token::Value op,
                                       OverwriteMode mode) {
    __ mov(a0, result_register());
    __ pop(a1);
    Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), op, mode).code();
    JumpPatchSite patch_site(masm_);    // unbound, signals no inlined smi code.
    CallIC(code, expr->BinaryOperationFeedbackId());
    patch_site.EmitPatchInfo();
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitAssignment(Expression* expr) {
    DCHECK(expr->IsValidReferenceExpression());
  
    Property* prop = expr->AsProperty();
    LhsKind assign_type = GetAssignType(prop);
  
    switch (assign_type) {
      case VARIABLE: {
        Variable* var = expr->AsVariableProxy()->var();
        EffectContext context(this);
        EmitVariableAssignment(var, Token::ASSIGN);
        break;
      }
      case NAMED_PROPERTY: {
        __ push(result_register());  // Preserve value.
        VisitForAccumulatorValue(prop->obj());
        __ mov(StoreDescriptor::ReceiverRegister(), result_register());
        __ pop(StoreDescriptor::ValueRegister());  // Restore value.
        __ li(StoreDescriptor::NameRegister(),
              Operand(prop->key()->AsLiteral()->value()));
        CallStoreIC();
        break;
      }
      case NAMED_SUPER_PROPERTY: {
        __ Push(v0);
        VisitForStackValue(prop->obj()->AsSuperReference()->this_var());
        EmitLoadHomeObject(prop->obj()->AsSuperReference());
        // stack: value, this; v0: home_object
        Register scratch = a2;
        Register scratch2 = a3;
        __ mov(scratch, result_register());             // home_object
        __ lw(v0, MemOperand(sp, kPointerSize));        // value
        __ lw(scratch2, MemOperand(sp, 0));             // this
        __ sw(scratch2, MemOperand(sp, kPointerSize));  // this
        __ sw(scratch, MemOperand(sp, 0));              // home_object
        // stack: this, home_object; v0: value
        EmitNamedSuperPropertyStore(prop);
        break;
      }
      case KEYED_SUPER_PROPERTY: {
        __ Push(v0);
        VisitForStackValue(prop->obj()->AsSuperReference()->this_var());
        EmitLoadHomeObject(prop->obj()->AsSuperReference());
        __ Push(result_register());
        VisitForAccumulatorValue(prop->key());
        Register scratch = a2;
        Register scratch2 = a3;
        __ lw(scratch2, MemOperand(sp, 2 * kPointerSize));  // value
        // stack: value, this, home_object; v0: key, a3: value
        __ lw(scratch, MemOperand(sp, kPointerSize));  // this
        __ sw(scratch, MemOperand(sp, 2 * kPointerSize));
        __ lw(scratch, MemOperand(sp, 0));  // home_object
        __ sw(scratch, MemOperand(sp, kPointerSize));
        __ sw(v0, MemOperand(sp, 0));
        __ Move(v0, scratch2);
        // stack: this, home_object, key; v0: value.
        EmitKeyedSuperPropertyStore(prop);
        break;
      }
      case KEYED_PROPERTY: {
        __ push(result_register());  // Preserve value.
        VisitForStackValue(prop->obj());
        VisitForAccumulatorValue(prop->key());
        __ mov(StoreDescriptor::NameRegister(), result_register());
        __ Pop(StoreDescriptor::ValueRegister(),
               StoreDescriptor::ReceiverRegister());
        Handle<Code> ic =
            CodeFactory::KeyedStoreIC(isolate(), strict_mode()).code();
        CallIC(ic);
        break;
      }
    }
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitStoreToStackLocalOrContextSlot(
      Variable* var, MemOperand location) {
    __ sw(result_register(), location);
    if (var->IsContextSlot()) {
      // RecordWrite may destroy all its register arguments.
      __ Move(a3, result_register());
      int offset = Context::SlotOffset(var->index());
      __ RecordWriteContextSlot(
          a1, offset, a3, a2, kRAHasBeenSaved, kDontSaveFPRegs);
    }
  }
  
  
  void FullCodeGenerator::EmitVariableAssignment(Variable* var, Token::Value op) {
    if (var->IsUnallocated()) {
      // Global var, const, or let.
      __ mov(StoreDescriptor::ValueRegister(), result_register());
      __ li(StoreDescriptor::NameRegister(), Operand(var->name()));
      __ lw(StoreDescriptor::ReceiverRegister(), GlobalObjectOperand());
      CallStoreIC();
  
    } else if (op == Token::INIT_CONST_LEGACY) {
      // Const initializers need a write barrier.
      DCHECK(!var->IsParameter());  // No const parameters.
      if (var->IsLookupSlot()) {
        __ li(a0, Operand(var->name()));
        __ Push(v0, cp, a0);  // Context and name.
        __ CallRuntime(Runtime::kInitializeLegacyConstLookupSlot, 3);
      } else {
        DCHECK(var->IsStackAllocated() || var->IsContextSlot());
        Label skip;
        MemOperand location = VarOperand(var, a1);
        __ lw(a2, location);
        __ LoadRoot(at, Heap::kTheHoleValueRootIndex);
        __ Branch(&skip, ne, a2, Operand(at));
        EmitStoreToStackLocalOrContextSlot(var, location);
        __ bind(&skip);
      }
  
    } else if (var->mode() == LET && op != Token::INIT_LET) {
      // Non-initializing assignment to let variable needs a write barrier.
      DCHECK(!var->IsLookupSlot());
      DCHECK(var->IsStackAllocated() || var->IsContextSlot());
      Label assign;
      MemOperand location = VarOperand(var, a1);
      __ lw(a3, location);
      __ LoadRoot(t0, Heap::kTheHoleValueRootIndex);
      __ Branch(&assign, ne, a3, Operand(t0));
      __ li(a3, Operand(var->name()));
      __ push(a3);
      __ CallRuntime(Runtime::kThrowReferenceError, 1);
      // Perform the assignment.
      __ bind(&assign);
      EmitStoreToStackLocalOrContextSlot(var, location);
  
    } else if (!var->is_const_mode() || op == Token::INIT_CONST) {
      if (var->IsLookupSlot()) {
        // Assignment to var.
        __ li(a1, Operand(var->name()));
        __ li(a0, Operand(Smi::FromInt(strict_mode())));
        __ Push(v0, cp, a1, a0);  // Value, context, name, strict mode.
        __ CallRuntime(Runtime::kStoreLookupSlot, 4);
      } else {
        // Assignment to var or initializing assignment to let/const in harmony
        // mode.
        DCHECK((var->IsStackAllocated() || var->IsContextSlot()));
        MemOperand location = VarOperand(var, a1);
        if (generate_debug_code_ && op == Token::INIT_LET) {
          // Check for an uninitialized let binding.
          __ lw(a2, location);
          __ LoadRoot(t0, Heap::kTheHoleValueRootIndex);
          __ Check(eq, kLetBindingReInitialization, a2, Operand(t0));
        }
        EmitStoreToStackLocalOrContextSlot(var, location);
      }
    }
    // Non-initializing assignments to consts are ignored.
  }
  
  
  void FullCodeGenerator::EmitNamedPropertyAssignment(Assignment* expr) {
    // Assignment to a property, using a named store IC.
    Property* prop = expr->target()->AsProperty();
    DCHECK(prop != NULL);
    DCHECK(prop->key()->IsLiteral());
  
    // Record source code position before IC call.
    SetSourcePosition(expr->position());
    __ mov(StoreDescriptor::ValueRegister(), result_register());
    __ li(StoreDescriptor::NameRegister(),
          Operand(prop->key()->AsLiteral()->value()));
    __ pop(StoreDescriptor::ReceiverRegister());
    CallStoreIC(expr->AssignmentFeedbackId());
  
    PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitNamedSuperPropertyStore(Property* prop) {
    // Assignment to named property of super.
    // v0 : value
    // stack : receiver ('this'), home_object
    DCHECK(prop != NULL);
    Literal* key = prop->key()->AsLiteral();
    DCHECK(key != NULL);
  
    __ Push(key->value());
    __ Push(v0);
    __ CallRuntime((strict_mode() == STRICT ? Runtime::kStoreToSuper_Strict
                                            : Runtime::kStoreToSuper_Sloppy),
                   4);
  }
  
  
  void FullCodeGenerator::EmitKeyedSuperPropertyStore(Property* prop) {
    // Assignment to named property of super.
    // v0 : value
    // stack : receiver ('this'), home_object, key
    DCHECK(prop != NULL);
  
    __ Push(v0);
    __ CallRuntime((strict_mode() == STRICT ? Runtime::kStoreKeyedToSuper_Strict
                                            : Runtime::kStoreKeyedToSuper_Sloppy),
                   4);
  }
  
  
  void FullCodeGenerator::EmitKeyedPropertyAssignment(Assignment* expr) {
    // Assignment to a property, using a keyed store IC.
  
    // Record source code position before IC call.
    SetSourcePosition(expr->position());
    // Call keyed store IC.
    // The arguments are:
    // - a0 is the value,
    // - a1 is the key,
    // - a2 is the receiver.
    __ mov(StoreDescriptor::ValueRegister(), result_register());
    __ Pop(StoreDescriptor::ReceiverRegister(), StoreDescriptor::NameRegister());
    DCHECK(StoreDescriptor::ValueRegister().is(a0));
  
    Handle<Code> ic = CodeFactory::KeyedStoreIC(isolate(), strict_mode()).code();
    CallIC(ic, expr->AssignmentFeedbackId());
  
    PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::VisitProperty(Property* expr) {
    Comment cmnt(masm_, "[ Property");
    Expression* key = expr->key();
  
    if (key->IsPropertyName()) {
      if (!expr->IsSuperAccess()) {
        VisitForAccumulatorValue(expr->obj());
        __ Move(LoadDescriptor::ReceiverRegister(), v0);
        EmitNamedPropertyLoad(expr);
      } else {
        VisitForStackValue(expr->obj()->AsSuperReference()->this_var());
        EmitLoadHomeObject(expr->obj()->AsSuperReference());
        __ Push(result_register());
        EmitNamedSuperPropertyLoad(expr);
      }
      PrepareForBailoutForId(expr->LoadId(), TOS_REG);
      context()->Plug(v0);
    } else {
      if (!expr->IsSuperAccess()) {
        VisitForStackValue(expr->obj());
        VisitForAccumulatorValue(expr->key());
        __ Move(LoadDescriptor::NameRegister(), v0);
        __ pop(LoadDescriptor::ReceiverRegister());
        EmitKeyedPropertyLoad(expr);
      } else {
        VisitForStackValue(expr->obj()->AsSuperReference()->this_var());
        EmitLoadHomeObject(expr->obj()->AsSuperReference());
        __ Push(result_register());
        VisitForStackValue(expr->key());
        EmitKeyedSuperPropertyLoad(expr);
      }
      context()->Plug(v0);
    }
  }
  
  
  void FullCodeGenerator::CallIC(Handle<Code> code,
                                 TypeFeedbackId id) {
    ic_total_count_++;
    __ Call(code, RelocInfo::CODE_TARGET, id);
  }
  
  
  // Code common for calls using the IC.
  void FullCodeGenerator::EmitCallWithLoadIC(Call* expr) {
    Expression* callee = expr->expression();
  
    CallICState::CallType call_type =
        callee->IsVariableProxy() ? CallICState::FUNCTION : CallICState::METHOD;
  
    // Get the target function.
    if (call_type == CallICState::FUNCTION) {
      { StackValueContext context(this);
        EmitVariableLoad(callee->AsVariableProxy());
        PrepareForBailout(callee, NO_REGISTERS);
      }
      // Push undefined as receiver. This is patched in the method prologue if it
      // is a sloppy mode method.
      __ Push(isolate()->factory()->undefined_value());
    } else {
      // Load the function from the receiver.
      DCHECK(callee->IsProperty());
      DCHECK(!callee->AsProperty()->IsSuperAccess());
      __ lw(LoadDescriptor::ReceiverRegister(), MemOperand(sp, 0));
      EmitNamedPropertyLoad(callee->AsProperty());
      PrepareForBailoutForId(callee->AsProperty()->LoadId(), TOS_REG);
      // Push the target function under the receiver.
      __ lw(at, MemOperand(sp, 0));
      __ push(at);
      __ sw(v0, MemOperand(sp, kPointerSize));
    }
  
    EmitCall(expr, call_type);
  }
  
  
  void FullCodeGenerator::EmitSuperCallWithLoadIC(Call* expr) {
    Expression* callee = expr->expression();
    DCHECK(callee->IsProperty());
    Property* prop = callee->AsProperty();
    DCHECK(prop->IsSuperAccess());
  
    SetSourcePosition(prop->position());
    Literal* key = prop->key()->AsLiteral();
    DCHECK(!key->value()->IsSmi());
    // Load the function from the receiver.
    const Register scratch = a1;
    SuperReference* super_ref = prop->obj()->AsSuperReference();
    EmitLoadHomeObject(super_ref);
    __ mov(scratch, v0);
    VisitForAccumulatorValue(super_ref->this_var());
    __ Push(scratch, v0, v0, scratch);
    __ Push(key->value());
  
    // Stack here:
    //  - home_object
    //  - this (receiver)
    //  - this (receiver) <-- LoadFromSuper will pop here and below.
    //  - home_object
    //  - key
    __ CallRuntime(Runtime::kLoadFromSuper, 3);
  
    // Replace home_object with target function.
    __ sw(v0, MemOperand(sp, kPointerSize));
  
    // Stack here:
    // - target function
    // - this (receiver)
    EmitCall(expr, CallICState::METHOD);
  }
  
  
  // Code common for calls using the IC.
  void FullCodeGenerator::EmitKeyedCallWithLoadIC(Call* expr,
                                                  Expression* key) {
    // Load the key.
    VisitForAccumulatorValue(key);
  
    Expression* callee = expr->expression();
  
    // Load the function from the receiver.
    DCHECK(callee->IsProperty());
    __ lw(LoadDescriptor::ReceiverRegister(), MemOperand(sp, 0));
    __ Move(LoadDescriptor::NameRegister(), v0);
    EmitKeyedPropertyLoad(callee->AsProperty());
    PrepareForBailoutForId(callee->AsProperty()->LoadId(), TOS_REG);
  
    // Push the target function under the receiver.
    __ lw(at, MemOperand(sp, 0));
    __ push(at);
    __ sw(v0, MemOperand(sp, kPointerSize));
  
    EmitCall(expr, CallICState::METHOD);
  }
  
  
  void FullCodeGenerator::EmitKeyedSuperCallWithLoadIC(Call* expr) {
    Expression* callee = expr->expression();
    DCHECK(callee->IsProperty());
    Property* prop = callee->AsProperty();
    DCHECK(prop->IsSuperAccess());
  
    SetSourcePosition(prop->position());
    // Load the function from the receiver.
    const Register scratch = a1;
    SuperReference* super_ref = prop->obj()->AsSuperReference();
    EmitLoadHomeObject(super_ref);
    __ Move(scratch, v0);
    VisitForAccumulatorValue(super_ref->this_var());
    __ Push(scratch, v0, v0, scratch);
    VisitForStackValue(prop->key());
  
    // Stack here:
    //  - home_object
    //  - this (receiver)
    //  - this (receiver) <-- LoadKeyedFromSuper will pop here and below.
    //  - home_object
    //  - key
    __ CallRuntime(Runtime::kLoadKeyedFromSuper, 3);
  
    // Replace home_object with target function.
    __ sw(v0, MemOperand(sp, kPointerSize));
  
    // Stack here:
    // - target function
    // - this (receiver)
    EmitCall(expr, CallICState::METHOD);
  }
  
  
  void FullCodeGenerator::EmitCall(Call* expr, CallICState::CallType call_type) {
    // Load the arguments.
    ZoneList<Expression*>* args = expr->arguments();
    int arg_count = args->length();
    { PreservePositionScope scope(masm()->positions_recorder());
      for (int i = 0; i < arg_count; i++) {
        VisitForStackValue(args->at(i));
      }
    }
  
    // Record source position of the IC call.
    SetSourcePosition(expr->position());
    Handle<Code> ic = CallIC::initialize_stub(
        isolate(), arg_count, call_type);
    __ li(a3, Operand(SmiFromSlot(expr->CallFeedbackSlot())));
    __ lw(a1, MemOperand(sp, (arg_count + 1) * kPointerSize));
    // Don't assign a type feedback id to the IC, since type feedback is provided
    // by the vector above.
    CallIC(ic);
  
    RecordJSReturnSite(expr);
    // Restore context register.
    __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
    context()->DropAndPlug(1, v0);
  }
  
  
  void FullCodeGenerator::EmitResolvePossiblyDirectEval(int arg_count) {
    // t2: copy of the first argument or undefined if it doesn't exist.
    if (arg_count > 0) {
      __ lw(t2, MemOperand(sp, arg_count * kPointerSize));
    } else {
      __ LoadRoot(t2, Heap::kUndefinedValueRootIndex);
    }
  
    // t1: the receiver of the enclosing function.
    int receiver_offset = 2 + info_->scope()->num_parameters();
    __ lw(t1, MemOperand(fp, receiver_offset * kPointerSize));
  
    // t0: the strict mode.
    __ li(t0, Operand(Smi::FromInt(strict_mode())));
  
    // a1: the start position of the scope the calls resides in.
    __ li(a1, Operand(Smi::FromInt(scope()->start_position())));
  
    // Do the runtime call.
    __ Push(t2, t1, t0, a1);
    __ CallRuntime(Runtime::kResolvePossiblyDirectEval, 5);
  }
  
  
  void FullCodeGenerator::VisitCall(Call* expr) {
  #ifdef DEBUG
    // We want to verify that RecordJSReturnSite gets called on all paths
    // through this function.  Avoid early returns.
    expr->return_is_recorded_ = false;
  #endif
  
    Comment cmnt(masm_, "[ Call");
    Expression* callee = expr->expression();
    Call::CallType call_type = expr->GetCallType(isolate());
  
    if (call_type == Call::POSSIBLY_EVAL_CALL) {
      // In a call to eval, we first call RuntimeHidden_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.
      ZoneList<Expression*>* args = expr->arguments();
      int arg_count = args->length();
  
      { PreservePositionScope pos_scope(masm()->positions_recorder());
        VisitForStackValue(callee);
        __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
        __ push(a2);  // Reserved receiver slot.
  
        // Push the arguments.
        for (int i = 0; i < arg_count; i++) {
          VisitForStackValue(args->at(i));
        }
  
        // Push a copy of the function (found below the arguments) and
        // resolve eval.
        __ lw(a1, MemOperand(sp, (arg_count + 1) * kPointerSize));
        __ push(a1);
        EmitResolvePossiblyDirectEval(arg_count);
  
        // The runtime call returns a pair of values in v0 (function) and
        // v1 (receiver). Touch up the stack with the right values.
        __ sw(v0, MemOperand(sp, (arg_count + 1) * kPointerSize));
        __ sw(v1, MemOperand(sp, arg_count * kPointerSize));
  
        PrepareForBailoutForId(expr->EvalOrLookupId(), NO_REGISTERS);
      }
      // Record source position for debugger.
      SetSourcePosition(expr->position());
      CallFunctionStub stub(isolate(), arg_count, NO_CALL_FUNCTION_FLAGS);
      __ lw(a1, MemOperand(sp, (arg_count + 1) * kPointerSize));
      __ CallStub(&stub);
      RecordJSReturnSite(expr);
      // Restore context register.
      __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
      context()->DropAndPlug(1, v0);
    } else if (call_type == Call::GLOBAL_CALL) {
      EmitCallWithLoadIC(expr);
    } else if (call_type == Call::LOOKUP_SLOT_CALL) {
      // Call to a lookup slot (dynamically introduced variable).
      VariableProxy* proxy = callee->AsVariableProxy();
      Label slow, done;
  
      { PreservePositionScope scope(masm()->positions_recorder());
        // Generate code for loading from variables potentially shadowed
        // by eval-introduced variables.
        EmitDynamicLookupFastCase(proxy, NOT_INSIDE_TYPEOF, &slow, &done);
      }
  
      __ bind(&slow);
      // Call the runtime to find the function to call (returned in v0)
      // and the object holding it (returned in v1).
      DCHECK(!context_register().is(a2));
      __ li(a2, Operand(proxy->name()));
      __ Push(context_register(), a2);
      __ CallRuntime(Runtime::kLoadLookupSlot, 2);
      __ Push(v0, v1);  // Function, receiver.
      PrepareForBailoutForId(expr->EvalOrLookupId(), NO_REGISTERS);
  
      // If fast case code has been generated, emit code to push the
      // function and receiver and have the slow path jump around this
      // code.
      if (done.is_linked()) {
        Label call;
        __ Branch(&call);
        __ bind(&done);
        // Push function.
        __ push(v0);
        // The receiver is implicitly the global receiver. Indicate this
        // by passing the hole to the call function stub.
        __ LoadRoot(a1, Heap::kUndefinedValueRootIndex);
        __ push(a1);
        __ bind(&call);
      }
  
      // The receiver is either the global receiver or an object found
      // by LoadContextSlot.
      EmitCall(expr);
    } else if (call_type == Call::PROPERTY_CALL) {
      Property* property = callee->AsProperty();
      bool is_named_call = property->key()->IsPropertyName();
      if (property->IsSuperAccess()) {
        if (is_named_call) {
          EmitSuperCallWithLoadIC(expr);
        } else {
          EmitKeyedSuperCallWithLoadIC(expr);
        }
      } else {
        {
          PreservePositionScope scope(masm()->positions_recorder());
          VisitForStackValue(property->obj());
        }
        if (is_named_call) {
          EmitCallWithLoadIC(expr);
        } else {
          EmitKeyedCallWithLoadIC(expr, property->key());
        }
      }
    } else {
      DCHECK(call_type == Call::OTHER_CALL);
      // Call to an arbitrary expression not handled specially above.
      { PreservePositionScope scope(masm()->positions_recorder());
        VisitForStackValue(callee);
      }
      __ LoadRoot(a1, Heap::kUndefinedValueRootIndex);
      __ push(a1);
      // Emit function call.
      EmitCall(expr);
    }
  
  #ifdef DEBUG
    // RecordJSReturnSite should have been called.
    DCHECK(expr->return_is_recorded_);
  #endif
  }
  
  
  void FullCodeGenerator::VisitCallNew(CallNew* expr) {
    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.
  
    // Push constructor on the stack.  If it's not a function it's used as
    // receiver for CALL_NON_FUNCTION, otherwise the value on the stack is
    // ignored.
    VisitForStackValue(expr->expression());
  
    // Push the arguments ("left-to-right") on the stack.
    ZoneList<Expression*>* args = expr->arguments();
    int arg_count = args->length();
    for (int i = 0; i < arg_count; i++) {
      VisitForStackValue(args->at(i));
    }
  
    // Call the construct call builtin that handles allocation and
    // constructor invocation.
    SetSourcePosition(expr->position());
  
    // Load function and argument count into a1 and a0.
    __ li(a0, Operand(arg_count));
    __ lw(a1, MemOperand(sp, arg_count * kPointerSize));
  
    // Record call targets in unoptimized code.
    if (FLAG_pretenuring_call_new) {
      EnsureSlotContainsAllocationSite(expr->AllocationSiteFeedbackSlot());
      DCHECK(expr->AllocationSiteFeedbackSlot().ToInt() ==
             expr->CallNewFeedbackSlot().ToInt() + 1);
    }
  
    __ li(a2, FeedbackVector());
    __ li(a3, Operand(SmiFromSlot(expr->CallNewFeedbackSlot())));
  
    CallConstructStub stub(isolate(), RECORD_CONSTRUCTOR_TARGET);
    __ Call(stub.GetCode(), RelocInfo::CONSTRUCT_CALL);
    PrepareForBailoutForId(expr->ReturnId(), TOS_REG);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitIsSmi(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    __ SmiTst(v0, t0);
    Split(eq, t0, Operand(zero_reg), if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsNonNegativeSmi(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    __ NonNegativeSmiTst(v0, at);
    Split(eq, at, Operand(zero_reg), if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsObject(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ JumpIfSmi(v0, if_false);
    __ LoadRoot(at, Heap::kNullValueRootIndex);
    __ Branch(if_true, eq, v0, Operand(at));
    __ lw(a2, FieldMemOperand(v0, HeapObject::kMapOffset));
    // Undetectable objects behave like undefined when tested with typeof.
    __ lbu(a1, FieldMemOperand(a2, Map::kBitFieldOffset));
    __ And(at, a1, Operand(1 << Map::kIsUndetectable));
    __ Branch(if_false, ne, at, Operand(zero_reg));
    __ lbu(a1, FieldMemOperand(a2, Map::kInstanceTypeOffset));
    __ Branch(if_false, lt, a1, Operand(FIRST_NONCALLABLE_SPEC_OBJECT_TYPE));
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(le, a1, Operand(LAST_NONCALLABLE_SPEC_OBJECT_TYPE),
          if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsSpecObject(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ JumpIfSmi(v0, if_false);
    __ GetObjectType(v0, a1, a1);
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(ge, a1, Operand(FIRST_SPEC_OBJECT_TYPE),
          if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsUndetectableObject(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ JumpIfSmi(v0, if_false);
    __ lw(a1, FieldMemOperand(v0, HeapObject::kMapOffset));
    __ lbu(a1, FieldMemOperand(a1, Map::kBitFieldOffset));
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    __ And(at, a1, Operand(1 << Map::kIsUndetectable));
    Split(ne, at, Operand(zero_reg), if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsStringWrapperSafeForDefaultValueOf(
      CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false, skip_lookup;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ AssertNotSmi(v0);
  
    __ lw(a1, FieldMemOperand(v0, HeapObject::kMapOffset));
    __ lbu(t0, FieldMemOperand(a1, Map::kBitField2Offset));
    __ And(t0, t0, 1 << Map::kStringWrapperSafeForDefaultValueOf);
    __ Branch(&skip_lookup, ne, t0, Operand(zero_reg));
  
    // Check for fast case object. Generate false result for slow case object.
    __ lw(a2, FieldMemOperand(v0, JSObject::kPropertiesOffset));
    __ lw(a2, FieldMemOperand(a2, HeapObject::kMapOffset));
    __ LoadRoot(t0, Heap::kHashTableMapRootIndex);
    __ Branch(if_false, eq, a2, Operand(t0));
  
    // Look for valueOf name in the descriptor array, and indicate false if
    // found. Since we omit an enumeration index check, if it is added via a
    // transition that shares its descriptor array, this is a false positive.
    Label entry, loop, done;
  
    // Skip loop if no descriptors are valid.
    __ NumberOfOwnDescriptors(a3, a1);
    __ Branch(&done, eq, a3, Operand(zero_reg));
  
    __ LoadInstanceDescriptors(a1, t0);
    // t0: descriptor array.
    // a3: valid entries in the descriptor array.
    STATIC_ASSERT(kSmiTag == 0);
    STATIC_ASSERT(kSmiTagSize == 1);
    STATIC_ASSERT(kPointerSize == 4);
    __ li(at, Operand(DescriptorArray::kDescriptorSize));
    __ Mul(a3, a3, at);
    // Calculate location of the first key name.
    __ Addu(t0, t0, Operand(DescriptorArray::kFirstOffset - kHeapObjectTag));
    // Calculate the end of the descriptor array.
    __ mov(a2, t0);
    __ sll(t1, a3, kPointerSizeLog2);
    __ Addu(a2, a2, t1);
  
    // Loop through all the keys in the descriptor array. If one of these is the
    // string "valueOf" the result is false.
    // The use of t2 to store the valueOf string assumes that it is not otherwise
    // used in the loop below.
    __ li(t2, Operand(isolate()->factory()->value_of_string()));
    __ jmp(&entry);
    __ bind(&loop);
    __ lw(a3, MemOperand(t0, 0));
    __ Branch(if_false, eq, a3, Operand(t2));
    __ Addu(t0, t0, Operand(DescriptorArray::kDescriptorSize * kPointerSize));
    __ bind(&entry);
    __ Branch(&loop, ne, t0, Operand(a2));
  
    __ bind(&done);
  
    // Set the bit in the map to indicate that there is no local valueOf field.
    __ lbu(a2, FieldMemOperand(a1, Map::kBitField2Offset));
    __ Or(a2, a2, Operand(1 << Map::kStringWrapperSafeForDefaultValueOf));
    __ sb(a2, FieldMemOperand(a1, Map::kBitField2Offset));
  
    __ bind(&skip_lookup);
  
    // If a valueOf property is not found on the object check that its
    // prototype is the un-modified String prototype. If not result is false.
    __ lw(a2, FieldMemOperand(a1, Map::kPrototypeOffset));
    __ JumpIfSmi(a2, if_false);
    __ lw(a2, FieldMemOperand(a2, HeapObject::kMapOffset));
    __ lw(a3, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
    __ lw(a3, FieldMemOperand(a3, GlobalObject::kNativeContextOffset));
    __ lw(a3, ContextOperand(a3, Context::STRING_FUNCTION_PROTOTYPE_MAP_INDEX));
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(eq, a2, Operand(a3), if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsFunction(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ JumpIfSmi(v0, if_false);
    __ GetObjectType(v0, a1, a2);
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    __ Branch(if_true, eq, a2, Operand(JS_FUNCTION_TYPE));
    __ Branch(if_false);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsMinusZero(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ CheckMap(v0, a1, Heap::kHeapNumberMapRootIndex, if_false, DO_SMI_CHECK);
    __ lw(a2, FieldMemOperand(v0, HeapNumber::kExponentOffset));
    __ lw(a1, FieldMemOperand(v0, HeapNumber::kMantissaOffset));
    __ li(t0, 0x80000000);
    Label not_nan;
    __ Branch(&not_nan, ne, a2, Operand(t0));
    __ mov(t0, zero_reg);
    __ mov(a2, a1);
    __ bind(&not_nan);
  
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(eq, a2, Operand(t0), if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsArray(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ JumpIfSmi(v0, if_false);
    __ GetObjectType(v0, a1, a1);
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(eq, a1, Operand(JS_ARRAY_TYPE),
          if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsRegExp(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ JumpIfSmi(v0, if_false);
    __ GetObjectType(v0, a1, a1);
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(eq, a1, Operand(JS_REGEXP_TYPE), if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitIsConstructCall(CallRuntime* expr) {
    DCHECK(expr->arguments()->length() == 0);
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    // Get the frame pointer for the calling frame.
    __ lw(a2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
  
    // Skip the arguments adaptor frame if it exists.
    Label check_frame_marker;
    __ lw(a1, MemOperand(a2, StandardFrameConstants::kContextOffset));
    __ Branch(&check_frame_marker, ne,
              a1, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
    __ lw(a2, MemOperand(a2, StandardFrameConstants::kCallerFPOffset));
  
    // Check the marker in the calling frame.
    __ bind(&check_frame_marker);
    __ lw(a1, MemOperand(a2, StandardFrameConstants::kMarkerOffset));
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(eq, a1, Operand(Smi::FromInt(StackFrame::CONSTRUCT)),
          if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitObjectEquals(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 2);
  
    // Load the two objects into registers and perform the comparison.
    VisitForStackValue(args->at(0));
    VisitForAccumulatorValue(args->at(1));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ pop(a1);
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(eq, v0, Operand(a1), if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitArguments(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    // ArgumentsAccessStub expects the key in a1 and the formal
    // parameter count in a0.
    VisitForAccumulatorValue(args->at(0));
    __ mov(a1, v0);
    __ li(a0, Operand(Smi::FromInt(info_->scope()->num_parameters())));
    ArgumentsAccessStub stub(isolate(), ArgumentsAccessStub::READ_ELEMENT);
    __ CallStub(&stub);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitArgumentsLength(CallRuntime* expr) {
    DCHECK(expr->arguments()->length() == 0);
    Label exit;
    // Get the number of formal parameters.
    __ li(v0, Operand(Smi::FromInt(info_->scope()->num_parameters())));
  
    // Check if the calling frame is an arguments adaptor frame.
    __ lw(a2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
    __ lw(a3, MemOperand(a2, StandardFrameConstants::kContextOffset));
    __ Branch(&exit, ne, a3,
              Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
  
    // Arguments adaptor case: Read the arguments length from the
    // adaptor frame.
    __ lw(v0, MemOperand(a2, ArgumentsAdaptorFrameConstants::kLengthOffset));
  
    __ bind(&exit);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitClassOf(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
    Label done, null, function, non_function_constructor;
  
    VisitForAccumulatorValue(args->at(0));
  
    // If the object is a smi, we return null.
    __ JumpIfSmi(v0, &null);
  
    // Check that the object is a JS object but take special care of JS
    // functions to make sure they have 'Function' as their class.
    // Assume that there are only two callable types, and one of them is at
    // either end of the type range for JS object types. Saves extra comparisons.
    STATIC_ASSERT(NUM_OF_CALLABLE_SPEC_OBJECT_TYPES == 2);
    __ GetObjectType(v0, v0, a1);  // Map is now in v0.
    __ Branch(&null, lt, a1, Operand(FIRST_SPEC_OBJECT_TYPE));
  
    STATIC_ASSERT(FIRST_NONCALLABLE_SPEC_OBJECT_TYPE ==
                  FIRST_SPEC_OBJECT_TYPE + 1);
    __ Branch(&function, eq, a1, Operand(FIRST_SPEC_OBJECT_TYPE));
  
    STATIC_ASSERT(LAST_NONCALLABLE_SPEC_OBJECT_TYPE ==
                  LAST_SPEC_OBJECT_TYPE - 1);
    __ Branch(&function, eq, a1, Operand(LAST_SPEC_OBJECT_TYPE));
    // Assume that there is no larger type.
    STATIC_ASSERT(LAST_NONCALLABLE_SPEC_OBJECT_TYPE == LAST_TYPE - 1);
  
    // Check if the constructor in the map is a JS function.
    __ lw(v0, FieldMemOperand(v0, Map::kConstructorOffset));
    __ GetObjectType(v0, a1, a1);
    __ Branch(&non_function_constructor, ne, a1, Operand(JS_FUNCTION_TYPE));
  
    // v0 now contains the constructor function. Grab the
    // instance class name from there.
    __ lw(v0, FieldMemOperand(v0, JSFunction::kSharedFunctionInfoOffset));
    __ lw(v0, FieldMemOperand(v0, SharedFunctionInfo::kInstanceClassNameOffset));
    __ Branch(&done);
  
    // Functions have class 'Function'.
    __ bind(&function);
    __ LoadRoot(v0, Heap::kFunction_stringRootIndex);
    __ jmp(&done);
  
    // Objects with a non-function constructor have class 'Object'.
    __ bind(&non_function_constructor);
    __ LoadRoot(v0, Heap::kObject_stringRootIndex);
    __ jmp(&done);
  
    // Non-JS objects have class null.
    __ bind(&null);
    __ LoadRoot(v0, Heap::kNullValueRootIndex);
  
    // All done.
    __ bind(&done);
  
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitSubString(CallRuntime* expr) {
    // Load the arguments on the stack and call the stub.
    SubStringStub stub(isolate());
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 3);
    VisitForStackValue(args->at(0));
    VisitForStackValue(args->at(1));
    VisitForStackValue(args->at(2));
    __ CallStub(&stub);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitRegExpExec(CallRuntime* expr) {
    // Load the arguments on the stack and call the stub.
    RegExpExecStub stub(isolate());
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 4);
    VisitForStackValue(args->at(0));
    VisitForStackValue(args->at(1));
    VisitForStackValue(args->at(2));
    VisitForStackValue(args->at(3));
    __ CallStub(&stub);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitValueOf(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));  // Load the object.
  
    Label done;
    // If the object is a smi return the object.
    __ JumpIfSmi(v0, &done);
    // If the object is not a value type, return the object.
    __ GetObjectType(v0, a1, a1);
    __ Branch(&done, ne, a1, Operand(JS_VALUE_TYPE));
  
    __ lw(v0, FieldMemOperand(v0, JSValue::kValueOffset));
  
    __ bind(&done);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitDateField(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 2);
    DCHECK_NE(NULL, args->at(1)->AsLiteral());
    Smi* index = Smi::cast(*(args->at(1)->AsLiteral()->value()));
  
    VisitForAccumulatorValue(args->at(0));  // Load the object.
  
    Label runtime, done, not_date_object;
    Register object = v0;
    Register result = v0;
    Register scratch0 = t5;
    Register scratch1 = a1;
  
    __ JumpIfSmi(object, &not_date_object);
    __ GetObjectType(object, scratch1, scratch1);
    __ Branch(&not_date_object, ne, scratch1, Operand(JS_DATE_TYPE));
  
    if (index->value() == 0) {
      __ lw(result, FieldMemOperand(object, JSDate::kValueOffset));
      __ jmp(&done);
    } else {
      if (index->value() < JSDate::kFirstUncachedField) {
        ExternalReference stamp = ExternalReference::date_cache_stamp(isolate());
        __ li(scratch1, Operand(stamp));
        __ lw(scratch1, MemOperand(scratch1));
        __ lw(scratch0, FieldMemOperand(object, JSDate::kCacheStampOffset));
        __ Branch(&runtime, ne, scratch1, Operand(scratch0));
        __ lw(result, FieldMemOperand(object, JSDate::kValueOffset +
                                              kPointerSize * index->value()));
        __ jmp(&done);
      }
      __ bind(&runtime);
      __ PrepareCallCFunction(2, scratch1);
      __ li(a1, Operand(index));
      __ Move(a0, object);
      __ CallCFunction(ExternalReference::get_date_field_function(isolate()), 2);
      __ jmp(&done);
    }
  
    __ bind(&not_date_object);
    __ CallRuntime(Runtime::kThrowNotDateError, 0);
    __ bind(&done);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitOneByteSeqStringSetChar(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK_EQ(3, args->length());
  
    Register string = v0;
    Register index = a1;
    Register value = a2;
  
    VisitForStackValue(args->at(0));        // index
    VisitForStackValue(args->at(1));        // value
    VisitForAccumulatorValue(args->at(2));  // string
    __ Pop(index, value);
  
    if (FLAG_debug_code) {
      __ SmiTst(value, at);
      __ Check(eq, kNonSmiValue, at, Operand(zero_reg));
      __ SmiTst(index, at);
      __ Check(eq, kNonSmiIndex, at, Operand(zero_reg));
      __ SmiUntag(index, index);
      static const uint32_t one_byte_seq_type = kSeqStringTag | kOneByteStringTag;
      Register scratch = t5;
      __ EmitSeqStringSetCharCheck(
          string, index, value, scratch, one_byte_seq_type);
      __ SmiTag(index, index);
    }
  
    __ SmiUntag(value, value);
    __ Addu(at,
            string,
            Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
    __ SmiUntag(index);
    __ Addu(at, at, index);
    __ sb(value, MemOperand(at));
    context()->Plug(string);
  }
  
  
  void FullCodeGenerator::EmitTwoByteSeqStringSetChar(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK_EQ(3, args->length());
  
    Register string = v0;
    Register index = a1;
    Register value = a2;
  
    VisitForStackValue(args->at(0));        // index
    VisitForStackValue(args->at(1));        // value
    VisitForAccumulatorValue(args->at(2));  // string
    __ Pop(index, value);
  
    if (FLAG_debug_code) {
      __ SmiTst(value, at);
      __ Check(eq, kNonSmiValue, at, Operand(zero_reg));
      __ SmiTst(index, at);
      __ Check(eq, kNonSmiIndex, at, Operand(zero_reg));
      __ SmiUntag(index, index);
      static const uint32_t two_byte_seq_type = kSeqStringTag | kTwoByteStringTag;
      Register scratch = t5;
      __ EmitSeqStringSetCharCheck(
          string, index, value, scratch, two_byte_seq_type);
      __ SmiTag(index, index);
    }
  
    __ SmiUntag(value, value);
    __ Addu(at,
            string,
            Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
    __ Addu(at, at, index);
    STATIC_ASSERT(kSmiTagSize == 1 && kSmiTag == 0);
    __ sh(value, MemOperand(at));
      context()->Plug(string);
  }
  
  
  void FullCodeGenerator::EmitMathPow(CallRuntime* expr) {
    // Load the arguments on the stack and call the runtime function.
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 2);
    VisitForStackValue(args->at(0));
    VisitForStackValue(args->at(1));
    MathPowStub stub(isolate(), MathPowStub::ON_STACK);
    __ CallStub(&stub);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitSetValueOf(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 2);
  
    VisitForStackValue(args->at(0));  // Load the object.
    VisitForAccumulatorValue(args->at(1));  // Load the value.
    __ pop(a1);  // v0 = value. a1 = object.
  
    Label done;
    // If the object is a smi, return the value.
    __ JumpIfSmi(a1, &done);
  
    // If the object is not a value type, return the value.
    __ GetObjectType(a1, a2, a2);
    __ Branch(&done, ne, a2, Operand(JS_VALUE_TYPE));
  
    // Store the value.
    __ sw(v0, FieldMemOperand(a1, JSValue::kValueOffset));
    // Update the write barrier.  Save the value as it will be
    // overwritten by the write barrier code and is needed afterward.
    __ mov(a2, v0);
    __ RecordWriteField(
        a1, JSValue::kValueOffset, a2, a3, kRAHasBeenSaved, kDontSaveFPRegs);
  
    __ bind(&done);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitNumberToString(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK_EQ(args->length(), 1);
  
    // Load the argument into a0 and call the stub.
    VisitForAccumulatorValue(args->at(0));
    __ mov(a0, result_register());
  
    NumberToStringStub stub(isolate());
    __ CallStub(&stub);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitStringCharFromCode(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
  
    VisitForAccumulatorValue(args->at(0));
  
    Label done;
    StringCharFromCodeGenerator generator(v0, a1);
    generator.GenerateFast(masm_);
    __ jmp(&done);
  
    NopRuntimeCallHelper call_helper;
    generator.GenerateSlow(masm_, call_helper);
  
    __ bind(&done);
    context()->Plug(a1);
  }
  
  
  void FullCodeGenerator::EmitStringCharCodeAt(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 2);
  
    VisitForStackValue(args->at(0));
    VisitForAccumulatorValue(args->at(1));
    __ mov(a0, result_register());
  
    Register object = a1;
    Register index = a0;
    Register result = v0;
  
    __ pop(object);
  
    Label need_conversion;
    Label index_out_of_range;
    Label done;
    StringCharCodeAtGenerator generator(object,
                                        index,
                                        result,
                                        &need_conversion,
                                        &need_conversion,
                                        &index_out_of_range,
                                        STRING_INDEX_IS_NUMBER);
    generator.GenerateFast(masm_);
    __ jmp(&done);
  
    __ bind(&index_out_of_range);
    // When the index is out of range, the spec requires us to return
    // NaN.
    __ LoadRoot(result, Heap::kNanValueRootIndex);
    __ jmp(&done);
  
    __ bind(&need_conversion);
    // Load the undefined value into the result register, which will
    // trigger conversion.
    __ LoadRoot(result, Heap::kUndefinedValueRootIndex);
    __ jmp(&done);
  
    NopRuntimeCallHelper call_helper;
    generator.GenerateSlow(masm_, call_helper);
  
    __ bind(&done);
    context()->Plug(result);
  }
  
  
  void FullCodeGenerator::EmitStringCharAt(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 2);
  
    VisitForStackValue(args->at(0));
    VisitForAccumulatorValue(args->at(1));
    __ mov(a0, result_register());
  
    Register object = a1;
    Register index = a0;
    Register scratch = a3;
    Register result = v0;
  
    __ pop(object);
  
    Label need_conversion;
    Label index_out_of_range;
    Label done;
    StringCharAtGenerator generator(object,
                                    index,
                                    scratch,
                                    result,
                                    &need_conversion,
                                    &need_conversion,
                                    &index_out_of_range,
                                    STRING_INDEX_IS_NUMBER);
    generator.GenerateFast(masm_);
    __ jmp(&done);
  
    __ bind(&index_out_of_range);
    // When the index is out of range, the spec requires us to return
    // the empty string.
    __ LoadRoot(result, Heap::kempty_stringRootIndex);
    __ jmp(&done);
  
    __ bind(&need_conversion);
    // Move smi zero into the result register, which will trigger
    // conversion.
    __ li(result, Operand(Smi::FromInt(0)));
    __ jmp(&done);
  
    NopRuntimeCallHelper call_helper;
    generator.GenerateSlow(masm_, call_helper);
  
    __ bind(&done);
    context()->Plug(result);
  }
  
  
  void FullCodeGenerator::EmitStringAdd(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK_EQ(2, args->length());
    VisitForStackValue(args->at(0));
    VisitForAccumulatorValue(args->at(1));
  
    __ pop(a1);
    __ mov(a0, result_register());  // StringAddStub requires args in a0, a1.
    StringAddStub stub(isolate(), STRING_ADD_CHECK_BOTH, NOT_TENURED);
    __ CallStub(&stub);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitStringCompare(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK_EQ(2, args->length());
  
    VisitForStackValue(args->at(0));
    VisitForStackValue(args->at(1));
  
    StringCompareStub stub(isolate());
    __ CallStub(&stub);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitCallFunction(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() >= 2);
  
    int arg_count = args->length() - 2;  // 2 ~ receiver and function.
    for (int i = 0; i < arg_count + 1; i++) {
      VisitForStackValue(args->at(i));
    }
    VisitForAccumulatorValue(args->last());  // Function.
  
    Label runtime, done;
    // Check for non-function argument (including proxy).
    __ JumpIfSmi(v0, &runtime);
    __ GetObjectType(v0, a1, a1);
    __ Branch(&runtime, ne, a1, Operand(JS_FUNCTION_TYPE));
  
    // InvokeFunction requires the function in a1. Move it in there.
    __ mov(a1, result_register());
    ParameterCount count(arg_count);
    __ InvokeFunction(a1, count, CALL_FUNCTION, NullCallWrapper());
    __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
    __ jmp(&done);
  
    __ bind(&runtime);
    __ push(v0);
    __ CallRuntime(Runtime::kCall, args->length());
    __ bind(&done);
  
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitRegExpConstructResult(CallRuntime* expr) {
    RegExpConstructResultStub stub(isolate());
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 3);
    VisitForStackValue(args->at(0));
    VisitForStackValue(args->at(1));
    VisitForAccumulatorValue(args->at(2));
    __ mov(a0, result_register());
    __ pop(a1);
    __ pop(a2);
    __ CallStub(&stub);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitGetFromCache(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK_EQ(2, args->length());
  
    DCHECK_NE(NULL, args->at(0)->AsLiteral());
    int cache_id = Smi::cast(*(args->at(0)->AsLiteral()->value()))->value();
  
    Handle<FixedArray> jsfunction_result_caches(
        isolate()->native_context()->jsfunction_result_caches());
    if (jsfunction_result_caches->length() <= cache_id) {
      __ Abort(kAttemptToUseUndefinedCache);
      __ LoadRoot(v0, Heap::kUndefinedValueRootIndex);
      context()->Plug(v0);
      return;
    }
  
    VisitForAccumulatorValue(args->at(1));
  
    Register key = v0;
    Register cache = a1;
    __ lw(cache, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
    __ lw(cache, FieldMemOperand(cache, GlobalObject::kNativeContextOffset));
    __ lw(cache,
           ContextOperand(
               cache, Context::JSFUNCTION_RESULT_CACHES_INDEX));
    __ lw(cache,
           FieldMemOperand(cache, FixedArray::OffsetOfElementAt(cache_id)));
  
  
    Label done, not_found;
    STATIC_ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
    __ lw(a2, FieldMemOperand(cache, JSFunctionResultCache::kFingerOffset));
    // a2 now holds finger offset as a smi.
    __ Addu(a3, cache, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
    // a3 now points to the start of fixed array elements.
    __ sll(at, a2, kPointerSizeLog2 - kSmiTagSize);
    __ addu(a3, a3, at);
    // a3 now points to key of indexed element of cache.
    __ lw(a2, MemOperand(a3));
    __ Branch(&not_found, ne, key, Operand(a2));
  
    __ lw(v0, MemOperand(a3, kPointerSize));
    __ Branch(&done);
  
    __ bind(&not_found);
    // Call runtime to perform the lookup.
    __ Push(cache, key);
    __ CallRuntime(Runtime::kGetFromCache, 2);
  
    __ bind(&done);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitHasCachedArrayIndex(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    VisitForAccumulatorValue(args->at(0));
  
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    __ lw(a0, FieldMemOperand(v0, String::kHashFieldOffset));
    __ And(a0, a0, Operand(String::kContainsCachedArrayIndexMask));
  
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    Split(eq, a0, Operand(zero_reg), if_true, if_false, fall_through);
  
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitGetCachedArrayIndex(CallRuntime* expr) {
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 1);
    VisitForAccumulatorValue(args->at(0));
  
    __ AssertString(v0);
  
    __ lw(v0, FieldMemOperand(v0, String::kHashFieldOffset));
    __ IndexFromHash(v0, v0);
  
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitFastOneByteArrayJoin(CallRuntime* expr) {
    Label bailout, done, one_char_separator, long_separator,
        non_trivial_array, not_size_one_array, loop,
        empty_separator_loop, one_char_separator_loop,
        one_char_separator_loop_entry, long_separator_loop;
    ZoneList<Expression*>* args = expr->arguments();
    DCHECK(args->length() == 2);
    VisitForStackValue(args->at(1));
    VisitForAccumulatorValue(args->at(0));
  
    // All aliases of the same register have disjoint lifetimes.
    Register array = v0;
    Register elements = no_reg;  // Will be v0.
    Register result = no_reg;  // Will be v0.
    Register separator = a1;
    Register array_length = a2;
    Register result_pos = no_reg;  // Will be a2.
    Register string_length = a3;
    Register string = t0;
    Register element = t1;
    Register elements_end = t2;
    Register scratch1 = t3;
    Register scratch2 = t5;
    Register scratch3 = t4;
  
    // Separator operand is on the stack.
    __ pop(separator);
  
    // Check that the array is a JSArray.
    __ JumpIfSmi(array, &bailout);
    __ GetObjectType(array, scratch1, scratch2);
    __ Branch(&bailout, ne, scratch2, Operand(JS_ARRAY_TYPE));
  
    // Check that the array has fast elements.
    __ CheckFastElements(scratch1, scratch2, &bailout);
  
    // If the array has length zero, return the empty string.
    __ lw(array_length, FieldMemOperand(array, JSArray::kLengthOffset));
    __ SmiUntag(array_length);
    __ Branch(&non_trivial_array, ne, array_length, Operand(zero_reg));
    __ LoadRoot(v0, Heap::kempty_stringRootIndex);
    __ Branch(&done);
  
    __ bind(&non_trivial_array);
  
    // Get the FixedArray containing array's elements.
    elements = array;
    __ lw(elements, FieldMemOperand(array, JSArray::kElementsOffset));
    array = no_reg;  // End of array's live range.
  
    // Check that all array elements are sequential one-byte strings, and
    // accumulate the sum of their lengths, as a smi-encoded value.
    __ mov(string_length, zero_reg);
    __ Addu(element,
            elements, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
    __ sll(elements_end, array_length, kPointerSizeLog2);
    __ Addu(elements_end, element, elements_end);
    // Loop condition: while (element < elements_end).
    // Live values in registers:
    //   elements: Fixed array of strings.
    //   array_length: Length of the fixed array of strings (not smi)
    //   separator: Separator string
    //   string_length: Accumulated sum of string lengths (smi).
    //   element: Current array element.
    //   elements_end: Array end.
    if (generate_debug_code_) {
      __ Assert(gt, kNoEmptyArraysHereInEmitFastOneByteArrayJoin, array_length,
                Operand(zero_reg));
    }
    __ bind(&loop);
    __ lw(string, MemOperand(element));
    __ Addu(element, element, kPointerSize);
    __ JumpIfSmi(string, &bailout);
    __ lw(scratch1, FieldMemOperand(string, HeapObject::kMapOffset));
    __ lbu(scratch1, FieldMemOperand(scratch1, Map::kInstanceTypeOffset));
    __ JumpIfInstanceTypeIsNotSequentialOneByte(scratch1, scratch2, &bailout);
    __ lw(scratch1, FieldMemOperand(string, SeqOneByteString::kLengthOffset));
    __ AdduAndCheckForOverflow(string_length, string_length, scratch1, scratch3);
    __ BranchOnOverflow(&bailout, scratch3);
    __ Branch(&loop, lt, element, Operand(elements_end));
  
    // If array_length is 1, return elements[0], a string.
    __ Branch(&not_size_one_array, ne, array_length, Operand(1));
    __ lw(v0, FieldMemOperand(elements, FixedArray::kHeaderSize));
    __ Branch(&done);
  
    __ bind(&not_size_one_array);
  
    // Live values in registers:
    //   separator: Separator string
    //   array_length: Length of the array.
    //   string_length: Sum of string lengths (smi).
    //   elements: FixedArray of strings.
  
    // Check that the separator is a flat one-byte string.
    __ JumpIfSmi(separator, &bailout);
    __ lw(scratch1, FieldMemOperand(separator, HeapObject::kMapOffset));
    __ lbu(scratch1, FieldMemOperand(scratch1, Map::kInstanceTypeOffset));
    __ JumpIfInstanceTypeIsNotSequentialOneByte(scratch1, scratch2, &bailout);
  
    // Add (separator length times array_length) - separator length to the
    // string_length to get the length of the result string. array_length is not
    // smi but the other values are, so the result is a smi.
    __ lw(scratch1, FieldMemOperand(separator, SeqOneByteString::kLengthOffset));
    __ Subu(string_length, string_length, Operand(scratch1));
    __ Mul(scratch3, scratch2, array_length, scratch1);
    // Check for smi overflow. No overflow if higher 33 bits of 64-bit result are
    // zero.
    __ Branch(&bailout, ne, scratch3, Operand(zero_reg));
    __ And(scratch3, scratch2, Operand(0x80000000));
    __ Branch(&bailout, ne, scratch3, Operand(zero_reg));
    __ AdduAndCheckForOverflow(string_length, string_length, scratch2, scratch3);
    __ BranchOnOverflow(&bailout, scratch3);
    __ SmiUntag(string_length);
  
    // Get first element in the array to free up the elements register to be used
    // for the result.
    __ Addu(element,
            elements, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
    result = elements;  // End of live range for elements.
    elements = no_reg;
    // Live values in registers:
    //   element: First array element
    //   separator: Separator string
    //   string_length: Length of result string (not smi)
    //   array_length: Length of the array.
    __ AllocateOneByteString(result, string_length, scratch1, scratch2,
                             elements_end, &bailout);
    // Prepare for looping. Set up elements_end to end of the array. Set
    // result_pos to the position of the result where to write the first
    // character.
    __ sll(elements_end, array_length, kPointerSizeLog2);
    __ Addu(elements_end, element, elements_end);
    result_pos = array_length;  // End of live range for array_length.
    array_length = no_reg;
    __ Addu(result_pos,
            result,
            Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
  
    // Check the length of the separator.
    __ lw(scratch1, FieldMemOperand(separator, SeqOneByteString::kLengthOffset));
    __ li(at, Operand(Smi::FromInt(1)));
    __ Branch(&one_char_separator, eq, scratch1, Operand(at));
    __ Branch(&long_separator, gt, scratch1, Operand(at));
  
    // Empty separator case.
    __ bind(&empty_separator_loop);
    // Live values in registers:
    //   result_pos: the position to which we are currently copying characters.
    //   element: Current array element.
    //   elements_end: Array end.
  
    // Copy next array element to the result.
    __ lw(string, MemOperand(element));
    __ Addu(element, element, kPointerSize);
    __ lw(string_length, FieldMemOperand(string, String::kLengthOffset));
    __ SmiUntag(string_length);
    __ Addu(string, string, SeqOneByteString::kHeaderSize - kHeapObjectTag);
    __ CopyBytes(string, result_pos, string_length, scratch1);
    // End while (element < elements_end).
    __ Branch(&empty_separator_loop, lt, element, Operand(elements_end));
    DCHECK(result.is(v0));
    __ Branch(&done);
  
    // One-character separator case.
    __ bind(&one_char_separator);
    // Replace separator with its one-byte character value.
    __ lbu(separator, FieldMemOperand(separator, SeqOneByteString::kHeaderSize));
    // Jump into the loop after the code that copies the separator, so the first
    // element is not preceded by a separator.
    __ jmp(&one_char_separator_loop_entry);
  
    __ bind(&one_char_separator_loop);
    // Live values in registers:
    //   result_pos: the position to which we are currently copying characters.
    //   element: Current array element.
    //   elements_end: Array end.
    //   separator: Single separator one-byte char (in lower byte).
  
    // Copy the separator character to the result.
    __ sb(separator, MemOperand(result_pos));
    __ Addu(result_pos, result_pos, 1);
  
    // Copy next array element to the result.
    __ bind(&one_char_separator_loop_entry);
    __ lw(string, MemOperand(element));
    __ Addu(element, element, kPointerSize);
    __ lw(string_length, FieldMemOperand(string, String::kLengthOffset));
    __ SmiUntag(string_length);
    __ Addu(string, string, SeqOneByteString::kHeaderSize - kHeapObjectTag);
    __ CopyBytes(string, result_pos, string_length, scratch1);
    // End while (element < elements_end).
    __ Branch(&one_char_separator_loop, lt, element, Operand(elements_end));
    DCHECK(result.is(v0));
    __ Branch(&done);
  
    // Long separator case (separator is more than one character). Entry is at the
    // label long_separator below.
    __ bind(&long_separator_loop);
    // Live values in registers:
    //   result_pos: the position to which we are currently copying characters.
    //   element: Current array element.
    //   elements_end: Array end.
    //   separator: Separator string.
  
    // Copy the separator to the result.
    __ lw(string_length, FieldMemOperand(separator, String::kLengthOffset));
    __ SmiUntag(string_length);
    __ Addu(string,
            separator,
            Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
    __ CopyBytes(string, result_pos, string_length, scratch1);
  
    __ bind(&long_separator);
    __ lw(string, MemOperand(element));
    __ Addu(element, element, kPointerSize);
    __ lw(string_length, FieldMemOperand(string, String::kLengthOffset));
    __ SmiUntag(string_length);
    __ Addu(string, string, SeqOneByteString::kHeaderSize - kHeapObjectTag);
    __ CopyBytes(string, result_pos, string_length, scratch1);
    // End while (element < elements_end).
    __ Branch(&long_separator_loop, lt, element, Operand(elements_end));
    DCHECK(result.is(v0));
    __ Branch(&done);
  
    __ bind(&bailout);
    __ LoadRoot(v0, Heap::kUndefinedValueRootIndex);
    __ bind(&done);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::EmitDebugIsActive(CallRuntime* expr) {
    DCHECK(expr->arguments()->length() == 0);
    ExternalReference debug_is_active =
        ExternalReference::debug_is_active_address(isolate());
    __ li(at, Operand(debug_is_active));
    __ lb(v0, MemOperand(at));
    __ SmiTag(v0);
    context()->Plug(v0);
  }
  
  
  void FullCodeGenerator::VisitCallRuntime(CallRuntime* expr) {
    if (expr->function() != NULL &&
        expr->function()->intrinsic_type == Runtime::INLINE) {
      Comment cmnt(masm_, "[ InlineRuntimeCall");
      EmitInlineRuntimeCall(expr);
      return;
    }
  
    Comment cmnt(masm_, "[ CallRuntime");
    ZoneList<Expression*>* args = expr->arguments();
    int arg_count = args->length();
  
    if (expr->is_jsruntime()) {
      // Push the builtins object as the receiver.
      Register receiver = LoadDescriptor::ReceiverRegister();
      __ lw(receiver, GlobalObjectOperand());
      __ lw(receiver, FieldMemOperand(receiver, GlobalObject::kBuiltinsOffset));
      __ push(receiver);
  
      // Load the function from the receiver.
      __ li(LoadDescriptor::NameRegister(), Operand(expr->name()));
      if (FLAG_vector_ics) {
        __ li(VectorLoadICDescriptor::SlotRegister(),
              Operand(SmiFromSlot(expr->CallRuntimeFeedbackSlot())));
        CallLoadIC(NOT_CONTEXTUAL);
      } else {
        CallLoadIC(NOT_CONTEXTUAL, expr->CallRuntimeFeedbackId());
      }
  
      // Push the target function under the receiver.
      __ lw(at, MemOperand(sp, 0));
      __ push(at);
      __ sw(v0, MemOperand(sp, kPointerSize));
  
      // Push the arguments ("left-to-right").
      int arg_count = args->length();
      for (int i = 0; i < arg_count; i++) {
        VisitForStackValue(args->at(i));
      }
  
      // Record source position of the IC call.
      SetSourcePosition(expr->position());
      CallFunctionStub stub(isolate(), arg_count, NO_CALL_FUNCTION_FLAGS);
      __ lw(a1, MemOperand(sp, (arg_count + 1) * kPointerSize));
      __ CallStub(&stub);
  
      // Restore context register.
      __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
  
      context()->DropAndPlug(1, v0);
    } else {
      // Push the arguments ("left-to-right").
      for (int i = 0; i < arg_count; i++) {
        VisitForStackValue(args->at(i));
      }
  
      // Call the C runtime function.
      __ CallRuntime(expr->function(), arg_count);
      context()->Plug(v0);
    }
  }
  
  
  void FullCodeGenerator::VisitUnaryOperation(UnaryOperation* expr) {
    switch (expr->op()) {
      case Token::DELETE: {
        Comment cmnt(masm_, "[ UnaryOperation (DELETE)");
        Property* property = expr->expression()->AsProperty();
        VariableProxy* proxy = expr->expression()->AsVariableProxy();
  
        if (property != NULL) {
          VisitForStackValue(property->obj());
          VisitForStackValue(property->key());
          __ li(a1, Operand(Smi::FromInt(strict_mode())));
          __ push(a1);
          __ InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION);
          context()->Plug(v0);
        } else if (proxy != NULL) {
          Variable* var = proxy->var();
          // Delete of an unqualified identifier is disallowed in strict mode
          // but "delete this" is allowed.
          DCHECK(strict_mode() == SLOPPY || var->is_this());
          if (var->IsUnallocated()) {
            __ lw(a2, GlobalObjectOperand());
            __ li(a1, Operand(var->name()));
            __ li(a0, Operand(Smi::FromInt(SLOPPY)));
            __ Push(a2, a1, a0);
            __ InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION);
            context()->Plug(v0);
          } else if (var->IsStackAllocated() || var->IsContextSlot()) {
            // Result of deleting non-global, non-dynamic variables is false.
            // The subexpression does not have side effects.
            context()->Plug(var->is_this());
          } else {
            // Non-global variable.  Call the runtime to try to delete from the
            // context where the variable was introduced.
            DCHECK(!context_register().is(a2));
            __ li(a2, Operand(var->name()));
            __ Push(context_register(), a2);
            __ CallRuntime(Runtime::kDeleteLookupSlot, 2);
            context()->Plug(v0);
          }
        } else {
          // Result of deleting non-property, non-variable reference is true.
          // The subexpression may have side effects.
          VisitForEffect(expr->expression());
          context()->Plug(true);
        }
        break;
      }
  
      case Token::VOID: {
        Comment cmnt(masm_, "[ UnaryOperation (VOID)");
        VisitForEffect(expr->expression());
        context()->Plug(Heap::kUndefinedValueRootIndex);
        break;
      }
  
      case Token::NOT: {
        Comment cmnt(masm_, "[ UnaryOperation (NOT)");
        if (context()->IsEffect()) {
          // Unary NOT has no side effects so it's only necessary to visit the
          // subexpression.  Match the optimizing compiler by not branching.
          VisitForEffect(expr->expression());
        } else if (context()->IsTest()) {
          const TestContext* test = TestContext::cast(context());
          // The labels are swapped for the recursive call.
          VisitForControl(expr->expression(),
                          test->false_label(),
                          test->true_label(),
                          test->fall_through());
          context()->Plug(test->true_label(), test->false_label());
        } else {
          // We handle value contexts explicitly rather than simply visiting
          // for control and plugging the control flow into the context,
          // because we need to prepare a pair of extra administrative AST ids
          // for the optimizing compiler.
          DCHECK(context()->IsAccumulatorValue() || context()->IsStackValue());
          Label materialize_true, materialize_false, done;
          VisitForControl(expr->expression(),
                          &materialize_false,
                          &materialize_true,
                          &materialize_true);
          __ bind(&materialize_true);
          PrepareForBailoutForId(expr->MaterializeTrueId(), NO_REGISTERS);
          __ LoadRoot(v0, Heap::kTrueValueRootIndex);
          if (context()->IsStackValue()) __ push(v0);
          __ jmp(&done);
          __ bind(&materialize_false);
          PrepareForBailoutForId(expr->MaterializeFalseId(), NO_REGISTERS);
          __ LoadRoot(v0, Heap::kFalseValueRootIndex);
          if (context()->IsStackValue()) __ push(v0);
          __ bind(&done);
        }
        break;
      }
  
      case Token::TYPEOF: {
        Comment cmnt(masm_, "[ UnaryOperation (TYPEOF)");
        { StackValueContext context(this);
          VisitForTypeofValue(expr->expression());
        }
        __ CallRuntime(Runtime::kTypeof, 1);
        context()->Plug(v0);
        break;
      }
  
      default:
        UNREACHABLE();
    }
  }
  
  
  void FullCodeGenerator::VisitCountOperation(CountOperation* expr) {
    DCHECK(expr->expression()->IsValidReferenceExpression());
  
    Comment cmnt(masm_, "[ CountOperation");
    SetSourcePosition(expr->position());
  
    Property* prop = expr->expression()->AsProperty();
    LhsKind assign_type = GetAssignType(prop);
  
    // Evaluate expression and get value.
    if (assign_type == VARIABLE) {
      DCHECK(expr->expression()->AsVariableProxy()->var() != NULL);
      AccumulatorValueContext context(this);
      EmitVariableLoad(expr->expression()->AsVariableProxy());
    } else {
      // Reserve space for result of postfix operation.
      if (expr->is_postfix() && !context()->IsEffect()) {
        __ li(at, Operand(Smi::FromInt(0)));
        __ push(at);
      }
      switch (assign_type) {
        case NAMED_PROPERTY: {
          // Put the object both on the stack and in the register.
          VisitForStackValue(prop->obj());
          __ lw(LoadDescriptor::ReceiverRegister(), MemOperand(sp, 0));
          EmitNamedPropertyLoad(prop);
          break;
        }
  
        case NAMED_SUPER_PROPERTY: {
          VisitForStackValue(prop->obj()->AsSuperReference()->this_var());
          EmitLoadHomeObject(prop->obj()->AsSuperReference());
          __ Push(result_register());
          const Register scratch = a1;
          __ lw(scratch, MemOperand(sp, kPointerSize));
          __ Push(scratch, result_register());
          EmitNamedSuperPropertyLoad(prop);
          break;
        }
  
        case KEYED_SUPER_PROPERTY: {
          VisitForStackValue(prop->obj()->AsSuperReference()->this_var());
          EmitLoadHomeObject(prop->obj()->AsSuperReference());
          const Register scratch = a1;
          const Register scratch1 = t0;
          __ Move(scratch, result_register());
          VisitForAccumulatorValue(prop->key());
          __ Push(scratch, result_register());
          __ lw(scratch1, MemOperand(sp, 2 * kPointerSize));
          __ Push(scratch1, scratch, result_register());
          EmitKeyedSuperPropertyLoad(prop);
          break;
        }
  
        case KEYED_PROPERTY: {
          VisitForStackValue(prop->obj());
          VisitForStackValue(prop->key());
          __ lw(LoadDescriptor::ReceiverRegister(),
                MemOperand(sp, 1 * kPointerSize));
          __ lw(LoadDescriptor::NameRegister(), MemOperand(sp, 0));
          EmitKeyedPropertyLoad(prop);
          break;
        }
  
        case VARIABLE:
          UNREACHABLE();
      }
    }
  
    // We need a second deoptimization point after loading the value
    // in case evaluating the property load my have a side effect.
    if (assign_type == VARIABLE) {
      PrepareForBailout(expr->expression(), TOS_REG);
    } else {
      PrepareForBailoutForId(prop->LoadId(), TOS_REG);
    }
  
    // Inline smi case if we are in a loop.
    Label stub_call, done;
    JumpPatchSite patch_site(masm_);
  
    int count_value = expr->op() == Token::INC ? 1 : -1;
    __ mov(a0, v0);
    if (ShouldInlineSmiCase(expr->op())) {
      Label slow;
      patch_site.EmitJumpIfNotSmi(v0, &slow);
  
      // Save result for postfix expressions.
      if (expr->is_postfix()) {
        if (!context()->IsEffect()) {
          // Save the result on the stack. If we have a named or keyed property
          // we store the result under the receiver that is currently on top
          // of the stack.
          switch (assign_type) {
            case VARIABLE:
              __ push(v0);
              break;
            case NAMED_PROPERTY:
              __ sw(v0, MemOperand(sp, kPointerSize));
              break;
            case NAMED_SUPER_PROPERTY:
              __ sw(v0, MemOperand(sp, 2 * kPointerSize));
              break;
            case KEYED_PROPERTY:
              __ sw(v0, MemOperand(sp, 2 * kPointerSize));
              break;
            case KEYED_SUPER_PROPERTY:
              __ sw(v0, MemOperand(sp, 3 * kPointerSize));
              break;
          }
        }
      }
  
      Register scratch1 = a1;
      Register scratch2 = t0;
      __ li(scratch1, Operand(Smi::FromInt(count_value)));
      __ AdduAndCheckForOverflow(v0, v0, scratch1, scratch2);
      __ BranchOnNoOverflow(&done, scratch2);
      // Call stub. Undo operation first.
      __ Move(v0, a0);
      __ jmp(&stub_call);
      __ bind(&slow);
    }
    ToNumberStub convert_stub(isolate());
    __ CallStub(&convert_stub);
  
    // Save result for postfix expressions.
    if (expr->is_postfix()) {
      if (!context()->IsEffect()) {
        // Save the result on the stack. If we have a named or keyed property
        // we store the result under the receiver that is currently on top
        // of the stack.
        switch (assign_type) {
          case VARIABLE:
            __ push(v0);
            break;
          case NAMED_PROPERTY:
            __ sw(v0, MemOperand(sp, kPointerSize));
            break;
          case NAMED_SUPER_PROPERTY:
            __ sw(v0, MemOperand(sp, 2 * kPointerSize));
            break;
          case KEYED_PROPERTY:
            __ sw(v0, MemOperand(sp, 2 * kPointerSize));
            break;
          case KEYED_SUPER_PROPERTY:
            __ sw(v0, MemOperand(sp, 3 * kPointerSize));
            break;
        }
      }
    }
  
    __ bind(&stub_call);
    __ mov(a1, v0);
    __ li(a0, Operand(Smi::FromInt(count_value)));
  
    // Record position before stub call.
    SetSourcePosition(expr->position());
  
    Handle<Code> code =
        CodeFactory::BinaryOpIC(isolate(), Token::ADD, NO_OVERWRITE).code();
    CallIC(code, expr->CountBinOpFeedbackId());
    patch_site.EmitPatchInfo();
    __ bind(&done);
  
    // Store the value returned in v0.
    switch (assign_type) {
      case VARIABLE:
        if (expr->is_postfix()) {
          { EffectContext context(this);
            EmitVariableAssignment(expr->expression()->AsVariableProxy()->var(),
                                   Token::ASSIGN);
            PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
            context.Plug(v0);
          }
          // For all contexts except EffectConstant we have the result on
          // top of the stack.
          if (!context()->IsEffect()) {
            context()->PlugTOS();
          }
        } else {
          EmitVariableAssignment(expr->expression()->AsVariableProxy()->var(),
                                 Token::ASSIGN);
          PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
          context()->Plug(v0);
        }
        break;
      case NAMED_PROPERTY: {
        __ mov(StoreDescriptor::ValueRegister(), result_register());
        __ li(StoreDescriptor::NameRegister(),
              Operand(prop->key()->AsLiteral()->value()));
        __ pop(StoreDescriptor::ReceiverRegister());
        CallStoreIC(expr->CountStoreFeedbackId());
        PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
        if (expr->is_postfix()) {
          if (!context()->IsEffect()) {
            context()->PlugTOS();
          }
        } else {
          context()->Plug(v0);
        }
        break;
      }
      case NAMED_SUPER_PROPERTY: {
        EmitNamedSuperPropertyStore(prop);
        if (expr->is_postfix()) {
          if (!context()->IsEffect()) {
            context()->PlugTOS();
          }
        } else {
          context()->Plug(v0);
        }
        break;
      }
      case KEYED_SUPER_PROPERTY: {
        EmitKeyedSuperPropertyStore(prop);
        if (expr->is_postfix()) {
          if (!context()->IsEffect()) {
            context()->PlugTOS();
          }
        } else {
          context()->Plug(v0);
        }
        break;
      }
      case KEYED_PROPERTY: {
        __ mov(StoreDescriptor::ValueRegister(), result_register());
        __ Pop(StoreDescriptor::ReceiverRegister(),
               StoreDescriptor::NameRegister());
        Handle<Code> ic =
            CodeFactory::KeyedStoreIC(isolate(), strict_mode()).code();
        CallIC(ic, expr->CountStoreFeedbackId());
        PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
        if (expr->is_postfix()) {
          if (!context()->IsEffect()) {
            context()->PlugTOS();
          }
        } else {
          context()->Plug(v0);
        }
        break;
      }
    }
  }
  
  
  void FullCodeGenerator::VisitForTypeofValue(Expression* expr) {
    DCHECK(!context()->IsEffect());
    DCHECK(!context()->IsTest());
    VariableProxy* proxy = expr->AsVariableProxy();
    if (proxy != NULL && proxy->var()->IsUnallocated()) {
      Comment cmnt(masm_, "[ Global variable");
      __ lw(LoadDescriptor::ReceiverRegister(), GlobalObjectOperand());
      __ li(LoadDescriptor::NameRegister(), Operand(proxy->name()));
      if (FLAG_vector_ics) {
        __ li(VectorLoadICDescriptor::SlotRegister(),
              Operand(SmiFromSlot(proxy->VariableFeedbackSlot())));
      }
      // Use a regular load, not a contextual load, to avoid a reference
      // error.
      CallLoadIC(NOT_CONTEXTUAL);
      PrepareForBailout(expr, TOS_REG);
      context()->Plug(v0);
    } else if (proxy != NULL && proxy->var()->IsLookupSlot()) {
      Comment cmnt(masm_, "[ Lookup slot");
      Label done, slow;
  
      // Generate code for loading from variables potentially shadowed
      // by eval-introduced variables.
      EmitDynamicLookupFastCase(proxy, INSIDE_TYPEOF, &slow, &done);
  
      __ bind(&slow);
      __ li(a0, Operand(proxy->name()));
      __ Push(cp, a0);
      __ CallRuntime(Runtime::kLoadLookupSlotNoReferenceError, 2);
      PrepareForBailout(expr, TOS_REG);
      __ bind(&done);
  
      context()->Plug(v0);
    } else {
      // This expression cannot throw a reference error at the top level.
      VisitInDuplicateContext(expr);
    }
  }
  
  void FullCodeGenerator::EmitLiteralCompareTypeof(Expression* expr,
                                                   Expression* sub_expr,
                                                   Handle<String> check) {
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    { AccumulatorValueContext context(this);
      VisitForTypeofValue(sub_expr);
    }
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
  
    Factory* factory = isolate()->factory();
    if (String::Equals(check, factory->number_string())) {
      __ JumpIfSmi(v0, if_true);
      __ lw(v0, FieldMemOperand(v0, HeapObject::kMapOffset));
      __ LoadRoot(at, Heap::kHeapNumberMapRootIndex);
      Split(eq, v0, Operand(at), if_true, if_false, fall_through);
    } else if (String::Equals(check, factory->string_string())) {
      __ JumpIfSmi(v0, if_false);
      // Check for undetectable objects => false.
      __ GetObjectType(v0, v0, a1);
      __ Branch(if_false, ge, a1, Operand(FIRST_NONSTRING_TYPE));
      __ lbu(a1, FieldMemOperand(v0, Map::kBitFieldOffset));
      __ And(a1, a1, Operand(1 << Map::kIsUndetectable));
      Split(eq, a1, Operand(zero_reg),
            if_true, if_false, fall_through);
    } else if (String::Equals(check, factory->symbol_string())) {
      __ JumpIfSmi(v0, if_false);
      __ GetObjectType(v0, v0, a1);
      Split(eq, a1, Operand(SYMBOL_TYPE), if_true, if_false, fall_through);
    } else if (String::Equals(check, factory->boolean_string())) {
      __ LoadRoot(at, Heap::kTrueValueRootIndex);
      __ Branch(if_true, eq, v0, Operand(at));
      __ LoadRoot(at, Heap::kFalseValueRootIndex);
      Split(eq, v0, Operand(at), if_true, if_false, fall_through);
    } else if (String::Equals(check, factory->undefined_string())) {
      __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
      __ Branch(if_true, eq, v0, Operand(at));
      __ JumpIfSmi(v0, if_false);
      // Check for undetectable objects => true.
      __ lw(v0, FieldMemOperand(v0, HeapObject::kMapOffset));
      __ lbu(a1, FieldMemOperand(v0, Map::kBitFieldOffset));
      __ And(a1, a1, Operand(1 << Map::kIsUndetectable));
      Split(ne, a1, Operand(zero_reg), if_true, if_false, fall_through);
    } else if (String::Equals(check, factory->function_string())) {
      __ JumpIfSmi(v0, if_false);
      STATIC_ASSERT(NUM_OF_CALLABLE_SPEC_OBJECT_TYPES == 2);
      __ GetObjectType(v0, v0, a1);
      __ Branch(if_true, eq, a1, Operand(JS_FUNCTION_TYPE));
      Split(eq, a1, Operand(JS_FUNCTION_PROXY_TYPE),
            if_true, if_false, fall_through);
    } else if (String::Equals(check, factory->object_string())) {
      __ JumpIfSmi(v0, if_false);
      __ LoadRoot(at, Heap::kNullValueRootIndex);
      __ Branch(if_true, eq, v0, Operand(at));
      // Check for JS objects => true.
      __ GetObjectType(v0, v0, a1);
      __ Branch(if_false, lt, a1, Operand(FIRST_NONCALLABLE_SPEC_OBJECT_TYPE));
      __ lbu(a1, FieldMemOperand(v0, Map::kInstanceTypeOffset));
      __ Branch(if_false, gt, a1, Operand(LAST_NONCALLABLE_SPEC_OBJECT_TYPE));
      // Check for undetectable objects => false.
      __ lbu(a1, FieldMemOperand(v0, Map::kBitFieldOffset));
      __ And(a1, a1, Operand(1 << Map::kIsUndetectable));
      Split(eq, a1, Operand(zero_reg), if_true, if_false, fall_through);
    } else {
      if (if_false != fall_through) __ jmp(if_false);
    }
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::VisitCompareOperation(CompareOperation* expr) {
    Comment cmnt(masm_, "[ CompareOperation");
    SetSourcePosition(expr->position());
  
    // First we try a fast inlined version of the compare when one of
    // the operands is a literal.
    if (TryLiteralCompare(expr)) return;
  
    // Always perform the comparison for its control flow.  Pack the result
    // into the expression's context after the comparison is performed.
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    Token::Value op = expr->op();
    VisitForStackValue(expr->left());
    switch (op) {
      case Token::IN:
        VisitForStackValue(expr->right());
        __ InvokeBuiltin(Builtins::IN, CALL_FUNCTION);
        PrepareForBailoutBeforeSplit(expr, false, NULL, NULL);
        __ LoadRoot(t0, Heap::kTrueValueRootIndex);
        Split(eq, v0, Operand(t0), if_true, if_false, fall_through);
        break;
  
      case Token::INSTANCEOF: {
        VisitForStackValue(expr->right());
        InstanceofStub stub(isolate(), InstanceofStub::kNoFlags);
        __ CallStub(&stub);
        PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
        // The stub returns 0 for true.
        Split(eq, v0, Operand(zero_reg), if_true, if_false, fall_through);
        break;
      }
  
      default: {
        VisitForAccumulatorValue(expr->right());
        Condition cc = CompareIC::ComputeCondition(op);
        __ mov(a0, result_register());
        __ pop(a1);
  
        bool inline_smi_code = ShouldInlineSmiCase(op);
        JumpPatchSite patch_site(masm_);
        if (inline_smi_code) {
          Label slow_case;
          __ Or(a2, a0, Operand(a1));
          patch_site.EmitJumpIfNotSmi(a2, &slow_case);
          Split(cc, a1, Operand(a0), if_true, if_false, NULL);
          __ bind(&slow_case);
        }
        // Record position and call the compare IC.
        SetSourcePosition(expr->position());
        Handle<Code> ic = CodeFactory::CompareIC(isolate(), op).code();
        CallIC(ic, expr->CompareOperationFeedbackId());
        patch_site.EmitPatchInfo();
        PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
        Split(cc, v0, Operand(zero_reg), if_true, if_false, fall_through);
      }
    }
  
    // Convert the result of the comparison into one expected for this
    // expression's context.
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::EmitLiteralCompareNil(CompareOperation* expr,
                                                Expression* sub_expr,
                                                NilValue nil) {
    Label materialize_true, materialize_false;
    Label* if_true = NULL;
    Label* if_false = NULL;
    Label* fall_through = NULL;
    context()->PrepareTest(&materialize_true, &materialize_false,
                           &if_true, &if_false, &fall_through);
  
    VisitForAccumulatorValue(sub_expr);
    PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
    __ mov(a0, result_register());
    if (expr->op() == Token::EQ_STRICT) {
      Heap::RootListIndex nil_value = nil == kNullValue ?
          Heap::kNullValueRootIndex :
          Heap::kUndefinedValueRootIndex;
      __ LoadRoot(a1, nil_value);
      Split(eq, a0, Operand(a1), if_true, if_false, fall_through);
    } else {
      Handle<Code> ic = CompareNilICStub::GetUninitialized(isolate(), nil);
      CallIC(ic, expr->CompareOperationFeedbackId());
      Split(ne, v0, Operand(zero_reg), if_true, if_false, fall_through);
    }
    context()->Plug(if_true, if_false);
  }
  
  
  void FullCodeGenerator::VisitThisFunction(ThisFunction* expr) {
    __ lw(v0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
    context()->Plug(v0);
  }
  
  
  Register FullCodeGenerator::result_register() {
    return v0;
  }
  
  
  Register FullCodeGenerator::context_register() {
    return cp;
  }
  
  
  void FullCodeGenerator::StoreToFrameField(int frame_offset, Register value) {
    DCHECK_EQ(POINTER_SIZE_ALIGN(frame_offset), frame_offset);
    __ sw(value, MemOperand(fp, frame_offset));
  }
  
  
  void FullCodeGenerator::LoadContextField(Register dst, int context_index) {
    __ lw(dst, ContextOperand(cp, context_index));
  }
  
  
  void FullCodeGenerator::PushFunctionArgumentForContextAllocation() {
    Scope* declaration_scope = scope()->DeclarationScope();
    if (declaration_scope->is_global_scope() ||
        declaration_scope->is_module_scope()) {
      // Contexts nested in the native context have a canonical empty function
      // as their closure, not the anonymous closure containing the global
      // code.  Pass a smi sentinel and let the runtime look up the empty
      // function.
      __ li(at, Operand(Smi::FromInt(0)));
    } else if (declaration_scope->is_eval_scope()) {
      // Contexts created by a call to eval have the same closure as the
      // context calling eval, not the anonymous closure containing the eval
      // code.  Fetch it from the context.
      __ lw(at, ContextOperand(cp, Context::CLOSURE_INDEX));
    } else {
      DCHECK(declaration_scope->is_function_scope());
      __ lw(at, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
    }
    __ push(at);
  }
  
  
  // ----------------------------------------------------------------------------
  // Non-local control flow support.
  
  void FullCodeGenerator::EnterFinallyBlock() {
    DCHECK(!result_register().is(a1));
    // Store result register while executing finally block.
    __ push(result_register());
    // Cook return address in link register to stack (smi encoded Code* delta).
    __ Subu(a1, ra, Operand(masm_->CodeObject()));
    DCHECK_EQ(1, kSmiTagSize + kSmiShiftSize);
    STATIC_ASSERT(0 == kSmiTag);
    __ Addu(a1, a1, Operand(a1));  // Convert to smi.
  
    // Store result register while executing finally block.
    __ push(a1);
  
    // Store pending message while executing finally block.
    ExternalReference pending_message_obj =
        ExternalReference::address_of_pending_message_obj(isolate());
    __ li(at, Operand(pending_message_obj));
    __ lw(a1, MemOperand(at));
    __ push(a1);
  
    ExternalReference has_pending_message =
        ExternalReference::address_of_has_pending_message(isolate());
    __ li(at, Operand(has_pending_message));
    __ lw(a1, MemOperand(at));
    __ SmiTag(a1);
    __ push(a1);
  
    ExternalReference pending_message_script =
        ExternalReference::address_of_pending_message_script(isolate());
    __ li(at, Operand(pending_message_script));
    __ lw(a1, MemOperand(at));
    __ push(a1);
  }
  
  
  void FullCodeGenerator::ExitFinallyBlock() {
    DCHECK(!result_register().is(a1));
    // Restore pending message from stack.
    __ pop(a1);
    ExternalReference pending_message_script =
        ExternalReference::address_of_pending_message_script(isolate());
    __ li(at, Operand(pending_message_script));
    __ sw(a1, MemOperand(at));
  
    __ pop(a1);
    __ SmiUntag(a1);
    ExternalReference has_pending_message =
        ExternalReference::address_of_has_pending_message(isolate());
    __ li(at, Operand(has_pending_message));
    __ sw(a1, MemOperand(at));
  
    __ pop(a1);
    ExternalReference pending_message_obj =
        ExternalReference::address_of_pending_message_obj(isolate());
    __ li(at, Operand(pending_message_obj));
    __ sw(a1, MemOperand(at));
  
    // Restore result register from stack.
    __ pop(a1);
  
    // Uncook return address and return.
    __ pop(result_register());
    DCHECK_EQ(1, kSmiTagSize + kSmiShiftSize);
    __ sra(a1, a1, 1);  // Un-smi-tag value.
    __ Addu(at, a1, Operand(masm_->CodeObject()));
    __ Jump(at);
  }
  
  
  #undef __
  
  #define __ ACCESS_MASM(masm())
  
  FullCodeGenerator::NestedStatement* FullCodeGenerator::TryFinally::Exit(
      int* stack_depth,
      int* context_length) {
    // The macros used here must preserve the result register.
  
    // Because the handler block contains the context of the finally
    // code, we can restore it directly from there for the finally code
    // rather than iteratively unwinding contexts via their previous
    // links.
    __ Drop(*stack_depth);  // Down to the handler block.
    if (*context_length > 0) {
      // Restore the context to its dedicated register and the stack.
      __ lw(cp, MemOperand(sp, StackHandlerConstants::kContextOffset));
      __ sw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
    }
    __ PopTryHandler();
    __ Call(finally_entry_);
  
    *stack_depth = 0;
    *context_length = 0;
    return previous_;
  }
  
  
  #undef __
  
  
  void BackEdgeTable::PatchAt(Code* unoptimized_code,
                              Address pc,
                              BackEdgeState target_state,
                              Code* replacement_code) {
    static const int kInstrSize = Assembler::kInstrSize;
    Address branch_address = pc - 6 * kInstrSize;
    CodePatcher patcher(branch_address, 1);
  
    switch (target_state) {
      case INTERRUPT:
        // slt at, a3, zero_reg (in case of count based interrupts)
        // beq at, zero_reg, ok
        // lui t9, <interrupt stub address> upper
        // ori t9, <interrupt stub address> lower
        // jalr t9
        // nop
        // ok-label ----- pc_after points here
        patcher.masm()->slt(at, a3, zero_reg);
        break;
      case ON_STACK_REPLACEMENT:
      case OSR_AFTER_STACK_CHECK:
        // addiu at, zero_reg, 1
        // beq at, zero_reg, ok  ;; Not changed
        // lui t9, <on-stack replacement address> upper
        // ori t9, <on-stack replacement address> lower
        // jalr t9  ;; Not changed
        // nop  ;; Not changed
        // ok-label ----- pc_after points here
        patcher.masm()->addiu(at, zero_reg, 1);
        break;
    }
    Address pc_immediate_load_address = pc - 4 * kInstrSize;
    // Replace the stack check address in the load-immediate (lui/ori pair)
    // with the entry address of the replacement code.
    Assembler::set_target_address_at(pc_immediate_load_address,
                                     replacement_code->entry());
  
    unoptimized_code->GetHeap()->incremental_marking()->RecordCodeTargetPatch(
        unoptimized_code, pc_immediate_load_address, replacement_code);
  }
  
  
  BackEdgeTable::BackEdgeState BackEdgeTable::GetBackEdgeState(
      Isolate* isolate,
      Code* unoptimized_code,
      Address pc) {
    static const int kInstrSize = Assembler::kInstrSize;
    Address branch_address = pc - 6 * kInstrSize;
    Address pc_immediate_load_address = pc - 4 * kInstrSize;
  
    DCHECK(Assembler::IsBeq(Assembler::instr_at(pc - 5 * kInstrSize)));
    if (!Assembler::IsAddImmediate(Assembler::instr_at(branch_address))) {
      DCHECK(reinterpret_cast<uint32_t>(
          Assembler::target_address_at(pc_immediate_load_address)) ==
             reinterpret_cast<uint32_t>(
                 isolate->builtins()->InterruptCheck()->entry()));
      return INTERRUPT;
    }
  
    DCHECK(Assembler::IsAddImmediate(Assembler::instr_at(branch_address)));
  
    if (reinterpret_cast<uint32_t>(
        Assembler::target_address_at(pc_immediate_load_address)) ==
            reinterpret_cast<uint32_t>(
                isolate->builtins()->OnStackReplacement()->entry())) {
      return ON_STACK_REPLACEMENT;
    }
  
    DCHECK(reinterpret_cast<uint32_t>(
        Assembler::target_address_at(pc_immediate_load_address)) ==
           reinterpret_cast<uint32_t>(
               isolate->builtins()->OsrAfterStackCheck()->entry()));
    return OSR_AFTER_STACK_CHECK;
  }
  
  
  } }  // namespace v8::internal
  
  #endif  // V8_TARGET_ARCH_MIPS
  