text: // Copyright 2012 the V8 project authors. All rights reserved.
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  //       notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  //       copyright notice, this list of conditions and the following
  //       disclaimer in the documentation and/or other materials provided
  //       with the distribution.
  //     * Neither the name of Google Inc. nor the names of its
  //       contributors may be used to endorse or promote products derived
  //       from this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  #include "v8.h"
  
  #if V8_TARGET_ARCH_IA32
  
  #include "codegen.h"
  #include "deoptimizer.h"
  #include "full-codegen.h"
  #include "stub-cache.h"
  
  namespace v8 {
  namespace internal {
  
  
  #define __ ACCESS_MASM(masm)
  
  
  void Builtins::Generate_Adaptor(MacroAssembler* masm,
                                  CFunctionId id,
                                  BuiltinExtraArguments extra_args) {
    // ----------- S t a t e -------------
    //  -- eax                : number of arguments excluding receiver
    //  -- edi                : called function (only guaranteed when
    //                          extra_args requires it)
    //  -- esi                : context
    //  -- esp[0]             : return address
    //  -- esp[4]             : last argument
    //  -- ...
    //  -- esp[4 * argc]      : first argument (argc == eax)
    //  -- esp[4 * (argc +1)] : receiver
    // -----------------------------------
  
    // Insert extra arguments.
    int num_extra_args = 0;
    if (extra_args == NEEDS_CALLED_FUNCTION) {
      num_extra_args = 1;
      Register scratch = ebx;
      __ pop(scratch);  // Save return address.
      __ push(edi);
      __ push(scratch);  // Restore return address.
    } else {
      ASSERT(extra_args == NO_EXTRA_ARGUMENTS);
    }
  
    // JumpToExternalReference expects eax to contain the number of arguments
    // including the receiver and the extra arguments.
    __ add(eax, Immediate(num_extra_args + 1));
    __ JumpToExternalReference(ExternalReference(id, masm->isolate()));
  }
  
  
  static void CallRuntimePassFunction(
      MacroAssembler* masm, Runtime::FunctionId function_id) {
    FrameScope scope(masm, StackFrame::INTERNAL);
    // Push a copy of the function.
    __ push(edi);
    // Function is also the parameter to the runtime call.
    __ push(edi);
  
    __ CallRuntime(function_id, 1);
    // Restore receiver.
    __ pop(edi);
  }
  
  
  static void GenerateTailCallToSharedCode(MacroAssembler* masm) {
    __ mov(eax, FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset));
    __ mov(eax, FieldOperand(eax, SharedFunctionInfo::kCodeOffset));
    __ lea(eax, FieldOperand(eax, Code::kHeaderSize));
    __ jmp(eax);
  }
  
  
  static void GenerateTailCallToReturnedCode(MacroAssembler* masm) {
    __ lea(eax, FieldOperand(eax, Code::kHeaderSize));
    __ jmp(eax);
  }
  
  
  void Builtins::Generate_InOptimizationQueue(MacroAssembler* masm) {
    // Checking whether the queued function is ready for install is optional,
    // since we come across interrupts and stack checks elsewhere.  However,
    // not checking may delay installing ready functions, and always checking
    // would be quite expensive.  A good compromise is to first check against
    // stack limit as a cue for an interrupt signal.
    Label ok;
    ExternalReference stack_limit =
        ExternalReference::address_of_stack_limit(masm->isolate());
    __ cmp(esp, Operand::StaticVariable(stack_limit));
    __ j(above_equal, &ok, Label::kNear);
  
    CallRuntimePassFunction(masm, Runtime::kTryInstallOptimizedCode);
    GenerateTailCallToReturnedCode(masm);
  
    __ bind(&ok);
    GenerateTailCallToSharedCode(masm);
  }
  
  
  static void Generate_JSConstructStubHelper(MacroAssembler* masm,
                                             bool is_api_function,
                                             bool count_constructions,
                                             bool create_memento) {
    // ----------- S t a t e -------------
    //  -- eax: number of arguments
    //  -- edi: constructor function
    //  -- ebx: allocation site or undefined
    // -----------------------------------
  
    // Should never count constructions for api objects.
    ASSERT(!is_api_function || !count_constructions);
  
    // Should never create mementos for api functions.
    ASSERT(!is_api_function || !create_memento);
  
    // Should never create mementos before slack tracking is finished.
    ASSERT(!count_constructions || !create_memento);
  
    // Enter a construct frame.
    {
      FrameScope scope(masm, StackFrame::CONSTRUCT);
  
      if (create_memento) {
        __ AssertUndefinedOrAllocationSite(ebx);
        __ push(ebx);
      }
  
      // Store a smi-tagged arguments count on the stack.
      __ SmiTag(eax);
      __ push(eax);
  
      // Push the function to invoke on the stack.
      __ push(edi);
  
      // Try to allocate the object without transitioning into C code. If any of
      // the preconditions is not met, the code bails out to the runtime call.
      Label rt_call, allocated;
      if (FLAG_inline_new) {
        Label undo_allocation;
  #ifdef ENABLE_DEBUGGER_SUPPORT
        ExternalReference debug_step_in_fp =
            ExternalReference::debug_step_in_fp_address(masm->isolate());
        __ cmp(Operand::StaticVariable(debug_step_in_fp), Immediate(0));
        __ j(not_equal, &rt_call);
  #endif
  
        // Verified that the constructor is a JSFunction.
        // Load the initial map and verify that it is in fact a map.
        // edi: constructor
        __ mov(eax, FieldOperand(edi, JSFunction::kPrototypeOrInitialMapOffset));
        // Will both indicate a NULL and a Smi
        __ JumpIfSmi(eax, &rt_call);
        // edi: constructor
        // eax: initial map (if proven valid below)
        __ CmpObjectType(eax, MAP_TYPE, ebx);
        __ j(not_equal, &rt_call);
  
        // Check that the constructor is not constructing a JSFunction (see
        // comments in Runtime_NewObject in runtime.cc). In which case the
        // initial map's instance type would be JS_FUNCTION_TYPE.
        // edi: constructor
        // eax: initial map
        __ CmpInstanceType(eax, JS_FUNCTION_TYPE);
        __ j(equal, &rt_call);
  
        if (count_constructions) {
          Label allocate;
          // Decrease generous allocation count.
          __ mov(ecx, FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset));
          __ dec_b(FieldOperand(ecx,
                                SharedFunctionInfo::kConstructionCountOffset));
          __ j(not_zero, &allocate);
  
          __ push(eax);
          __ push(edi);
  
          __ push(edi);  // constructor
          // The call will replace the stub, so the countdown is only done once.
          __ CallRuntime(Runtime::kFinalizeInstanceSize, 1);
  
          __ pop(edi);
          __ pop(eax);
  
          __ bind(&allocate);
        }
  
        // Now allocate the JSObject on the heap.
        // edi: constructor
        // eax: initial map
        __ movzx_b(edi, FieldOperand(eax, Map::kInstanceSizeOffset));
        __ shl(edi, kPointerSizeLog2);
        if (create_memento) {
          __ add(edi, Immediate(AllocationMemento::kSize));
        }
  
        __ Allocate(edi, ebx, edi, no_reg, &rt_call, NO_ALLOCATION_FLAGS);
  
        Factory* factory = masm->isolate()->factory();
  
        // Allocated the JSObject, now initialize the fields.
        // eax: initial map
        // ebx: JSObject
        // edi: start of next object (including memento if create_memento)
        __ mov(Operand(ebx, JSObject::kMapOffset), eax);
        __ mov(ecx, factory->empty_fixed_array());
        __ mov(Operand(ebx, JSObject::kPropertiesOffset), ecx);
        __ mov(Operand(ebx, JSObject::kElementsOffset), ecx);
        // Set extra fields in the newly allocated object.
        // eax: initial map
        // ebx: JSObject
        // edi: start of next object (including memento if create_memento)
        __ lea(ecx, Operand(ebx, JSObject::kHeaderSize));
        __ mov(edx, factory->undefined_value());
        if (count_constructions) {
          __ movzx_b(esi,
                     FieldOperand(eax, Map::kPreAllocatedPropertyFieldsOffset));
          __ lea(esi,
                 Operand(ebx, esi, times_pointer_size, JSObject::kHeaderSize));
          // esi: offset of first field after pre-allocated fields
          if (FLAG_debug_code) {
            __ cmp(esi, edi);
            __ Assert(less_equal,
                      kUnexpectedNumberOfPreAllocatedPropertyFields);
          }
          __ InitializeFieldsWithFiller(ecx, esi, edx);
          __ mov(edx, factory->one_pointer_filler_map());
          __ InitializeFieldsWithFiller(ecx, edi, edx);
        } else if (create_memento) {
          __ lea(esi, Operand(edi, -AllocationMemento::kSize));
          __ InitializeFieldsWithFiller(ecx, esi, edx);
  
          // Fill in memento fields if necessary.
          // esi: points to the allocated but uninitialized memento.
          Handle<Map> allocation_memento_map = factory->allocation_memento_map();
          __ mov(Operand(esi, AllocationMemento::kMapOffset),
                 allocation_memento_map);
          // Get the cell or undefined.
          __ mov(edx, Operand(esp, kPointerSize*2));
          __ mov(Operand(esi, AllocationMemento::kAllocationSiteOffset),
                 edx);
        } else {
          __ InitializeFieldsWithFiller(ecx, edi, edx);
        }
  
        // Add the object tag to make the JSObject real, so that we can continue
        // and jump into the continuation code at any time from now on. Any
        // failures need to undo the allocation, so that the heap is in a
        // consistent state and verifiable.
        // eax: initial map
        // ebx: JSObject
        // edi: start of next object
        __ or_(ebx, Immediate(kHeapObjectTag));
  
        // Check if a non-empty properties array is needed.
        // Allocate and initialize a FixedArray if it is.
        // eax: initial map
        // ebx: JSObject
        // edi: start of next object
        // Calculate the total number of properties described by the map.
        __ movzx_b(edx, FieldOperand(eax, Map::kUnusedPropertyFieldsOffset));
        __ movzx_b(ecx,
                   FieldOperand(eax, Map::kPreAllocatedPropertyFieldsOffset));
        __ add(edx, ecx);
        // Calculate unused properties past the end of the in-object properties.
        __ movzx_b(ecx, FieldOperand(eax, Map::kInObjectPropertiesOffset));
        __ sub(edx, ecx);
        // Done if no extra properties are to be allocated.
        __ j(zero, &allocated);
        __ Assert(positive, kPropertyAllocationCountFailed);
  
        // Scale the number of elements by pointer size and add the header for
        // FixedArrays to the start of the next object calculation from above.
        // ebx: JSObject
        // edi: start of next object (will be start of FixedArray)
        // edx: number of elements in properties array
        __ Allocate(FixedArray::kHeaderSize,
                    times_pointer_size,
                    edx,
                    REGISTER_VALUE_IS_INT32,
                    edi,
                    ecx,
                    no_reg,
                    &undo_allocation,
                    RESULT_CONTAINS_TOP);
  
        // Initialize the FixedArray.
        // ebx: JSObject
        // edi: FixedArray
        // edx: number of elements
        // ecx: start of next object
        __ mov(eax, factory->fixed_array_map());
        __ mov(Operand(edi, FixedArray::kMapOffset), eax);  // setup the map
        __ SmiTag(edx);
        __ mov(Operand(edi, FixedArray::kLengthOffset), edx);  // and length
  
        // Initialize the fields to undefined.
        // ebx: JSObject
        // edi: FixedArray
        // ecx: start of next object
        { Label loop, entry;
          __ mov(edx, factory->undefined_value());
          __ lea(eax, Operand(edi, FixedArray::kHeaderSize));
          __ jmp(&entry);
          __ bind(&loop);
          __ mov(Operand(eax, 0), edx);
          __ add(eax, Immediate(kPointerSize));
          __ bind(&entry);
          __ cmp(eax, ecx);
          __ j(below, &loop);
        }
  
        // Store the initialized FixedArray into the properties field of
        // the JSObject
        // ebx: JSObject
        // edi: FixedArray
        __ or_(edi, Immediate(kHeapObjectTag));  // add the heap tag
        __ mov(FieldOperand(ebx, JSObject::kPropertiesOffset), edi);
  
  
        // Continue with JSObject being successfully allocated
        // ebx: JSObject
        __ jmp(&allocated);
  
        // Undo the setting of the new top so that the heap is verifiable. For
        // example, the map's unused properties potentially do not match the
        // allocated objects unused properties.
        // ebx: JSObject (previous new top)
        __ bind(&undo_allocation);
        __ UndoAllocationInNewSpace(ebx);
      }
  
      // Allocate the new receiver object using the runtime call.
      __ bind(&rt_call);
      int offset = 0;
      if (create_memento) {
        // Get the cell or allocation site.
        __ mov(edi, Operand(esp, kPointerSize * 2));
        __ push(edi);
        offset = kPointerSize;
      }
  
      // Must restore edi (constructor) before calling runtime.
      __ mov(edi, Operand(esp, offset));
      // edi: function (constructor)
      __ push(edi);
      if (create_memento) {
        __ CallRuntime(Runtime::kNewObjectWithAllocationSite, 2);
      } else {
        __ CallRuntime(Runtime::kNewObject, 1);
      }
      __ mov(ebx, eax);  // store result in ebx
  
      // If we ended up using the runtime, and we want a memento, then the
      // runtime call made it for us, and we shouldn't do create count
      // increment.
      Label count_incremented;
      if (create_memento) {
        __ jmp(&count_incremented);
      }
  
      // New object allocated.
      // ebx: newly allocated object
      __ bind(&allocated);
  
      if (create_memento) {
        __ mov(ecx, Operand(esp, kPointerSize * 2));
        __ cmp(ecx, masm->isolate()->factory()->undefined_value());
        __ j(equal, &count_incremented);
        // ecx is an AllocationSite. We are creating a memento from it, so we
        // need to increment the memento create count.
        __ add(FieldOperand(ecx, AllocationSite::kPretenureCreateCountOffset),
               Immediate(Smi::FromInt(1)));
        __ bind(&count_incremented);
      }
  
      // Retrieve the function from the stack.
      __ pop(edi);
  
      // Retrieve smi-tagged arguments count from the stack.
      __ mov(eax, Operand(esp, 0));
      __ SmiUntag(eax);
  
      // Push the allocated receiver to the stack. We need two copies
      // because we may have to return the original one and the calling
      // conventions dictate that the called function pops the receiver.
      __ push(ebx);
      __ push(ebx);
  
      // Set up pointer to last argument.
      __ lea(ebx, Operand(ebp, StandardFrameConstants::kCallerSPOffset));
  
      // Copy arguments and receiver to the expression stack.
      Label loop, entry;
      __ mov(ecx, eax);
      __ jmp(&entry);
      __ bind(&loop);
      __ push(Operand(ebx, ecx, times_4, 0));
      __ bind(&entry);
      __ dec(ecx);
      __ j(greater_equal, &loop);
  
      // Call the function.
      if (is_api_function) {
        __ mov(esi, FieldOperand(edi, JSFunction::kContextOffset));
        Handle<Code> code =
            masm->isolate()->builtins()->HandleApiCallConstruct();
        __ call(code, RelocInfo::CODE_TARGET);
      } else {
        ParameterCount actual(eax);
        __ InvokeFunction(edi, actual, CALL_FUNCTION,
                          NullCallWrapper());
      }
  
      // Store offset of return address for deoptimizer.
      if (!is_api_function && !count_constructions) {
        masm->isolate()->heap()->SetConstructStubDeoptPCOffset(masm->pc_offset());
      }
  
      // Restore context from the frame.
      __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
  
      // If the result is an object (in the ECMA sense), we should get rid
      // of the receiver and use the result; see ECMA-262 section 13.2.2-7
      // on page 74.
      Label use_receiver, exit;
  
      // If the result is a smi, it is *not* an object in the ECMA sense.
      __ JumpIfSmi(eax, &use_receiver);
  
      // If the type of the result (stored in its map) is less than
      // FIRST_SPEC_OBJECT_TYPE, it is not an object in the ECMA sense.
      __ CmpObjectType(eax, FIRST_SPEC_OBJECT_TYPE, ecx);
      __ j(above_equal, &exit);
  
      // Throw away the result of the constructor invocation and use the
      // on-stack receiver as the result.
      __ bind(&use_receiver);
      __ mov(eax, Operand(esp, 0));
  
      // Restore the arguments count and leave the construct frame.
      __ bind(&exit);
      __ mov(ebx, Operand(esp, kPointerSize));  // Get arguments count.
  
      // Leave construct frame.
    }
  
    // Remove caller arguments from the stack and return.
    STATIC_ASSERT(kSmiTagSize == 1 && kSmiTag == 0);
    __ pop(ecx);
    __ lea(esp, Operand(esp, ebx, times_2, 1 * kPointerSize));  // 1 ~ receiver
    __ push(ecx);
    __ IncrementCounter(masm->isolate()->counters()->constructed_objects(), 1);
    __ ret(0);
  }
  
  
  void Builtins::Generate_JSConstructStubCountdown(MacroAssembler* masm) {
    Generate_JSConstructStubHelper(masm, false, true, false);
  }
  
  
  void Builtins::Generate_JSConstructStubGeneric(MacroAssembler* masm) {
    Generate_JSConstructStubHelper(masm, false, false, FLAG_pretenuring_call_new);
  }
  
  
  void Builtins::Generate_JSConstructStubApi(MacroAssembler* masm) {
    Generate_JSConstructStubHelper(masm, true, false, false);
  }
  
  
  static void Generate_JSEntryTrampolineHelper(MacroAssembler* masm,
                                               bool is_construct) {
    ProfileEntryHookStub::MaybeCallEntryHook(masm);
  
    // Clear the context before we push it when entering the internal frame.
    __ Set(esi, Immediate(0));
  
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
  
      // Load the previous frame pointer (ebx) to access C arguments
      __ mov(ebx, Operand(ebp, 0));
  
      // Get the function from the frame and setup the context.
      __ mov(ecx, Operand(ebx, EntryFrameConstants::kFunctionArgOffset));
      __ mov(esi, FieldOperand(ecx, JSFunction::kContextOffset));
  
      // Push the function and the receiver onto the stack.
      __ push(ecx);
      __ push(Operand(ebx, EntryFrameConstants::kReceiverArgOffset));
  
      // Load the number of arguments and setup pointer to the arguments.
      __ mov(eax, Operand(ebx, EntryFrameConstants::kArgcOffset));
      __ mov(ebx, Operand(ebx, EntryFrameConstants::kArgvOffset));
  
      // Copy arguments to the stack in a loop.
      Label loop, entry;
      __ Set(ecx, Immediate(0));
      __ jmp(&entry);
      __ bind(&loop);
      __ mov(edx, Operand(ebx, ecx, times_4, 0));  // push parameter from argv
      __ push(Operand(edx, 0));  // dereference handle
      __ inc(ecx);
      __ bind(&entry);
      __ cmp(ecx, eax);
      __ j(not_equal, &loop);
  
      // Get the function from the stack and call it.
      // kPointerSize for the receiver.
      __ mov(edi, Operand(esp, eax, times_4, kPointerSize));
  
      // Invoke the code.
      if (is_construct) {
        // No type feedback cell is available
        __ mov(ebx, masm->isolate()->factory()->undefined_value());
        CallConstructStub stub(NO_CALL_FUNCTION_FLAGS);
        __ CallStub(&stub);
      } else {
        ParameterCount actual(eax);
        __ InvokeFunction(edi, actual, CALL_FUNCTION,
                          NullCallWrapper());
      }
  
      // Exit the internal frame. Notice that this also removes the empty.
      // context and the function left on the stack by the code
      // invocation.
    }
    __ ret(kPointerSize);  // Remove receiver.
  }
  
  
  void Builtins::Generate_JSEntryTrampoline(MacroAssembler* masm) {
    Generate_JSEntryTrampolineHelper(masm, false);
  }
  
  
  void Builtins::Generate_JSConstructEntryTrampoline(MacroAssembler* masm) {
    Generate_JSEntryTrampolineHelper(masm, true);
  }
  
  
  void Builtins::Generate_CompileUnoptimized(MacroAssembler* masm) {
    CallRuntimePassFunction(masm, Runtime::kCompileUnoptimized);
    GenerateTailCallToReturnedCode(masm);
  }
  
  
  
  static void CallCompileOptimized(MacroAssembler* masm, bool concurrent) {
    FrameScope scope(masm, StackFrame::INTERNAL);
    // Push a copy of the function.
    __ push(edi);
    // Function is also the parameter to the runtime call.
    __ push(edi);
    // Whether to compile in a background thread.
    __ Push(masm->isolate()->factory()->ToBoolean(concurrent));
  
    __ CallRuntime(Runtime::kCompileOptimized, 2);
    // Restore receiver.
    __ pop(edi);
  }
  
  
  void Builtins::Generate_CompileOptimized(MacroAssembler* masm) {
    CallCompileOptimized(masm, false);
    GenerateTailCallToReturnedCode(masm);
  }
  
  
  void Builtins::Generate_CompileOptimizedConcurrent(MacroAssembler* masm) {
    CallCompileOptimized(masm, true);
    GenerateTailCallToReturnedCode(masm);
  }
  
  
  static void GenerateMakeCodeYoungAgainCommon(MacroAssembler* masm) {
    // For now, we are relying on the fact that make_code_young doesn't do any
    // garbage collection which allows us to save/restore the registers without
    // worrying about which of them contain pointers. We also don't build an
    // internal frame to make the code faster, since we shouldn't have to do stack
    // crawls in MakeCodeYoung. This seems a bit fragile.
  
    // Re-execute the code that was patched back to the young age when
    // the stub returns.
    __ sub(Operand(esp, 0), Immediate(5));
    __ pushad();
    __ mov(eax, Operand(esp, 8 * kPointerSize));
    {
      FrameScope scope(masm, StackFrame::MANUAL);
      __ PrepareCallCFunction(2, ebx);
      __ mov(Operand(esp, 1 * kPointerSize),
             Immediate(ExternalReference::isolate_address(masm->isolate())));
      __ mov(Operand(esp, 0), eax);
      __ CallCFunction(
          ExternalReference::get_make_code_young_function(masm->isolate()), 2);
    }
    __ popad();
    __ ret(0);
  }
  
  #define DEFINE_CODE_AGE_BUILTIN_GENERATOR(C)                 \
  void Builtins::Generate_Make##C##CodeYoungAgainEvenMarking(  \
      MacroAssembler* masm) {                                  \
    GenerateMakeCodeYoungAgainCommon(masm);                    \
  }                                                            \
  void Builtins::Generate_Make##C##CodeYoungAgainOddMarking(   \
      MacroAssembler* masm) {                                  \
    GenerateMakeCodeYoungAgainCommon(masm);                    \
  }
  CODE_AGE_LIST(DEFINE_CODE_AGE_BUILTIN_GENERATOR)
  #undef DEFINE_CODE_AGE_BUILTIN_GENERATOR
  
  
  void Builtins::Generate_MarkCodeAsExecutedOnce(MacroAssembler* masm) {
    // For now, as in GenerateMakeCodeYoungAgainCommon, we are relying on the fact
    // that make_code_young doesn't do any garbage collection which allows us to
    // save/restore the registers without worrying about which of them contain
    // pointers.
    __ pushad();
    __ mov(eax, Operand(esp, 8 * kPointerSize));
    __ sub(eax, Immediate(Assembler::kCallInstructionLength));
    {  // NOLINT
      FrameScope scope(masm, StackFrame::MANUAL);
      __ PrepareCallCFunction(2, ebx);
      __ mov(Operand(esp, 1 * kPointerSize),
             Immediate(ExternalReference::isolate_address(masm->isolate())));
      __ mov(Operand(esp, 0), eax);
      __ CallCFunction(
          ExternalReference::get_mark_code_as_executed_function(masm->isolate()),
          2);
    }
    __ popad();
  
    // Perform prologue operations usually performed by the young code stub.
    __ pop(eax);   // Pop return address into scratch register.
    __ push(ebp);  // Caller's frame pointer.
    __ mov(ebp, esp);
    __ push(esi);  // Callee's context.
    __ push(edi);  // Callee's JS Function.
    __ push(eax);  // Push return address after frame prologue.
  
    // Jump to point after the code-age stub.
    __ ret(0);
  }
  
  
  void Builtins::Generate_MarkCodeAsExecutedTwice(MacroAssembler* masm) {
    GenerateMakeCodeYoungAgainCommon(masm);
  }
  
  
  static void Generate_NotifyStubFailureHelper(MacroAssembler* masm,
                                               SaveFPRegsMode save_doubles) {
    // Enter an internal frame.
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
  
      // Preserve registers across notification, this is important for compiled
      // stubs that tail call the runtime on deopts passing their parameters in
      // registers.
      __ pushad();
      __ CallRuntime(Runtime::kNotifyStubFailure, 0, save_doubles);
      __ popad();
      // Tear down internal frame.
    }
  
    __ pop(MemOperand(esp, 0));  // Ignore state offset
    __ ret(0);  // Return to IC Miss stub, continuation still on stack.
  }
  
  
  void Builtins::Generate_NotifyStubFailure(MacroAssembler* masm) {
    Generate_NotifyStubFailureHelper(masm, kDontSaveFPRegs);
  }
  
  
  void Builtins::Generate_NotifyStubFailureSaveDoubles(MacroAssembler* masm) {
    if (Serializer::enabled()) {
      PlatformFeatureScope sse2(SSE2);
      Generate_NotifyStubFailureHelper(masm, kSaveFPRegs);
    } else {
      Generate_NotifyStubFailureHelper(masm, kSaveFPRegs);
    }
  }
  
  
  static void Generate_NotifyDeoptimizedHelper(MacroAssembler* masm,
                                               Deoptimizer::BailoutType type) {
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
  
      // Pass deoptimization type to the runtime system.
      __ push(Immediate(Smi::FromInt(static_cast<int>(type))));
      __ CallRuntime(Runtime::kNotifyDeoptimized, 1);
  
      // Tear down internal frame.
    }
  
    // Get the full codegen state from the stack and untag it.
    __ mov(ecx, Operand(esp, 1 * kPointerSize));
    __ SmiUntag(ecx);
  
    // Switch on the state.
    Label not_no_registers, not_tos_eax;
    __ cmp(ecx, FullCodeGenerator::NO_REGISTERS);
    __ j(not_equal, &not_no_registers, Label::kNear);
    __ ret(1 * kPointerSize);  // Remove state.
  
    __ bind(&not_no_registers);
    __ mov(eax, Operand(esp, 2 * kPointerSize));
    __ cmp(ecx, FullCodeGenerator::TOS_REG);
    __ j(not_equal, &not_tos_eax, Label::kNear);
    __ ret(2 * kPointerSize);  // Remove state, eax.
  
    __ bind(&not_tos_eax);
    __ Abort(kNoCasesLeft);
  }
  
  
  void Builtins::Generate_NotifyDeoptimized(MacroAssembler* masm) {
    Generate_NotifyDeoptimizedHelper(masm, Deoptimizer::EAGER);
  }
  
  
  void Builtins::Generate_NotifySoftDeoptimized(MacroAssembler* masm) {
    Generate_NotifyDeoptimizedHelper(masm, Deoptimizer::SOFT);
  }
  
  
  void Builtins::Generate_NotifyLazyDeoptimized(MacroAssembler* masm) {
    Generate_NotifyDeoptimizedHelper(masm, Deoptimizer::LAZY);
  }
  
  
  void Builtins::Generate_FunctionCall(MacroAssembler* masm) {
    Factory* factory = masm->isolate()->factory();
  
    // 1. Make sure we have at least one argument.
    { Label done;
      __ test(eax, eax);
      __ j(not_zero, &done);
      __ pop(ebx);
      __ push(Immediate(factory->undefined_value()));
      __ push(ebx);
      __ inc(eax);
      __ bind(&done);
    }
  
    // 2. Get the function to call (passed as receiver) from the stack, check
    //    if it is a function.
    Label slow, non_function;
    // 1 ~ return address.
    __ mov(edi, Operand(esp, eax, times_4, 1 * kPointerSize));
    __ JumpIfSmi(edi, &non_function);
    __ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
    __ j(not_equal, &slow);
  
  
    // 3a. Patch the first argument if necessary when calling a function.
    Label shift_arguments;
    __ Set(edx, Immediate(0));  // indicate regular JS_FUNCTION
    { Label convert_to_object, use_global_receiver, patch_receiver;
      // Change context eagerly in case we need the global receiver.
      __ mov(esi, FieldOperand(edi, JSFunction::kContextOffset));
  
      // Do not transform the receiver for strict mode functions.
      __ mov(ebx, FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset));
      __ test_b(FieldOperand(ebx, SharedFunctionInfo::kStrictModeByteOffset),
                1 << SharedFunctionInfo::kStrictModeBitWithinByte);
      __ j(not_equal, &shift_arguments);
  
      // Do not transform the receiver for natives (shared already in ebx).
      __ test_b(FieldOperand(ebx, SharedFunctionInfo::kNativeByteOffset),
                1 << SharedFunctionInfo::kNativeBitWithinByte);
      __ j(not_equal, &shift_arguments);
  
      // Compute the receiver in sloppy mode.
      __ mov(ebx, Operand(esp, eax, times_4, 0));  // First argument.
  
      // Call ToObject on the receiver if it is not an object, or use the
      // global object if it is null or undefined.
      __ JumpIfSmi(ebx, &convert_to_object);
      __ cmp(ebx, factory->null_value());
      __ j(equal, &use_global_receiver);
      __ cmp(ebx, factory->undefined_value());
      __ j(equal, &use_global_receiver);
      STATIC_ASSERT(LAST_SPEC_OBJECT_TYPE == LAST_TYPE);
      __ CmpObjectType(ebx, FIRST_SPEC_OBJECT_TYPE, ecx);
      __ j(above_equal, &shift_arguments);
  
      __ bind(&convert_to_object);
  
      { // In order to preserve argument count.
        FrameScope scope(masm, StackFrame::INTERNAL);
        __ SmiTag(eax);
        __ push(eax);
  
        __ push(ebx);
        __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
        __ mov(ebx, eax);
        __ Set(edx, Immediate(0));  // restore
  
        __ pop(eax);
        __ SmiUntag(eax);
      }
  
      // Restore the function to edi.
      __ mov(edi, Operand(esp, eax, times_4, 1 * kPointerSize));
      __ jmp(&patch_receiver);
  
      __ bind(&use_global_receiver);
      __ mov(ebx,
             Operand(esi, Context::SlotOffset(Context::GLOBAL_OBJECT_INDEX)));
      __ mov(ebx, FieldOperand(ebx, GlobalObject::kGlobalReceiverOffset));
  
      __ bind(&patch_receiver);
      __ mov(Operand(esp, eax, times_4, 0), ebx);
  
      __ jmp(&shift_arguments);
    }
  
    // 3b. Check for function proxy.
    __ bind(&slow);
    __ Set(edx, Immediate(1));  // indicate function proxy
    __ CmpInstanceType(ecx, JS_FUNCTION_PROXY_TYPE);
    __ j(equal, &shift_arguments);
    __ bind(&non_function);
    __ Set(edx, Immediate(2));  // indicate non-function
  
    // 3c. Patch the first argument when calling a non-function.  The
    //     CALL_NON_FUNCTION builtin expects the non-function callee as
    //     receiver, so overwrite the first argument which will ultimately
    //     become the receiver.
    __ mov(Operand(esp, eax, times_4, 0), edi);
  
    // 4. Shift arguments and return address one slot down on the stack
    //    (overwriting the original receiver).  Adjust argument count to make
    //    the original first argument the new receiver.
    __ bind(&shift_arguments);
    { Label loop;
      __ mov(ecx, eax);
      __ bind(&loop);
      __ mov(ebx, Operand(esp, ecx, times_4, 0));
      __ mov(Operand(esp, ecx, times_4, kPointerSize), ebx);
      __ dec(ecx);
      __ j(not_sign, &loop);  // While non-negative (to copy return address).
      __ pop(ebx);  // Discard copy of return address.
      __ dec(eax);  // One fewer argument (first argument is new receiver).
    }
  
    // 5a. Call non-function via tail call to CALL_NON_FUNCTION builtin,
    //     or a function proxy via CALL_FUNCTION_PROXY.
    { Label function, non_proxy;
      __ test(edx, edx);
      __ j(zero, &function);
      __ Set(ebx, Immediate(0));
      __ cmp(edx, Immediate(1));
      __ j(not_equal, &non_proxy);
  
      __ pop(edx);   // return address
      __ push(edi);  // re-add proxy object as additional argument
      __ push(edx);
      __ inc(eax);
      __ GetBuiltinEntry(edx, Builtins::CALL_FUNCTION_PROXY);
      __ jmp(masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),
             RelocInfo::CODE_TARGET);
  
      __ bind(&non_proxy);
      __ GetBuiltinEntry(edx, Builtins::CALL_NON_FUNCTION);
      __ jmp(masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),
             RelocInfo::CODE_TARGET);
      __ bind(&function);
    }
  
    // 5b. Get the code to call from the function and check that the number of
    //     expected arguments matches what we're providing.  If so, jump
    //     (tail-call) to the code in register edx without checking arguments.
    __ mov(edx, FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset));
    __ mov(ebx,
           FieldOperand(edx, SharedFunctionInfo::kFormalParameterCountOffset));
    __ mov(edx, FieldOperand(edi, JSFunction::kCodeEntryOffset));
    __ SmiUntag(ebx);
    __ cmp(eax, ebx);
    __ j(not_equal,
         masm->isolate()->builtins()->ArgumentsAdaptorTrampoline());
  
    ParameterCount expected(0);
    __ InvokeCode(edx, expected, expected, JUMP_FUNCTION, NullCallWrapper());
  }
  
  
  void Builtins::Generate_FunctionApply(MacroAssembler* masm) {
    static const int kArgumentsOffset = 2 * kPointerSize;
    static const int kReceiverOffset = 3 * kPointerSize;
    static const int kFunctionOffset = 4 * kPointerSize;
    {
      FrameScope frame_scope(masm, StackFrame::INTERNAL);
  
      __ push(Operand(ebp, kFunctionOffset));  // push this
      __ push(Operand(ebp, kArgumentsOffset));  // push arguments
      __ InvokeBuiltin(Builtins::APPLY_PREPARE, CALL_FUNCTION);
  
      // Check the stack for overflow. We are not trying to catch
      // interruptions (e.g. debug break and preemption) here, so the "real stack
      // limit" is checked.
      Label okay;
      ExternalReference real_stack_limit =
          ExternalReference::address_of_real_stack_limit(masm->isolate());
      __ mov(edi, Operand::StaticVariable(real_stack_limit));
      // Make ecx the space we have left. The stack might already be overflowed
      // here which will cause ecx to become negative.
      __ mov(ecx, esp);
      __ sub(ecx, edi);
      // Make edx the space we need for the array when it is unrolled onto the
      // stack.
      __ mov(edx, eax);
      __ shl(edx, kPointerSizeLog2 - kSmiTagSize);
      // Check if the arguments will overflow the stack.
      __ cmp(ecx, edx);
      __ j(greater, &okay);  // Signed comparison.
  
      // Out of stack space.
      __ push(Operand(ebp, 4 * kPointerSize));  // push this
      __ push(eax);
      __ InvokeBuiltin(Builtins::APPLY_OVERFLOW, CALL_FUNCTION);
      __ bind(&okay);
      // End of stack check.
  
      // Push current index and limit.
      const int kLimitOffset =
          StandardFrameConstants::kExpressionsOffset - 1 * kPointerSize;
      const int kIndexOffset = kLimitOffset - 1 * kPointerSize;
      __ push(eax);  // limit
      __ push(Immediate(0));  // index
  
      // Get the receiver.
      __ mov(ebx, Operand(ebp, kReceiverOffset));
  
      // Check that the function is a JS function (otherwise it must be a proxy).
      Label push_receiver, use_global_receiver;
      __ mov(edi, Operand(ebp, kFunctionOffset));
      __ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
      __ j(not_equal, &push_receiver);
  
      // Change context eagerly to get the right global object if necessary.
      __ mov(esi, FieldOperand(edi, JSFunction::kContextOffset));
  
      // Compute the receiver.
      // Do not transform the receiver for strict mode functions.
      Label call_to_object;
      __ mov(ecx, FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset));
      __ test_b(FieldOperand(ecx, SharedFunctionInfo::kStrictModeByteOffset),
                1 << SharedFunctionInfo::kStrictModeBitWithinByte);
      __ j(not_equal, &push_receiver);
  
      Factory* factory = masm->isolate()->factory();
  
      // Do not transform the receiver for natives (shared already in ecx).
      __ test_b(FieldOperand(ecx, SharedFunctionInfo::kNativeByteOffset),
                1 << SharedFunctionInfo::kNativeBitWithinByte);
      __ j(not_equal, &push_receiver);
  
      // Compute the receiver in sloppy mode.
      // Call ToObject on the receiver if it is not an object, or use the
      // global object if it is null or undefined.
      __ JumpIfSmi(ebx, &call_to_object);
      __ cmp(ebx, factory->null_value());
      __ j(equal, &use_global_receiver);
      __ cmp(ebx, factory->undefined_value());
      __ j(equal, &use_global_receiver);
      STATIC_ASSERT(LAST_SPEC_OBJECT_TYPE == LAST_TYPE);
      __ CmpObjectType(ebx, FIRST_SPEC_OBJECT_TYPE, ecx);
      __ j(above_equal, &push_receiver);
  
      __ bind(&call_to_object);
      __ push(ebx);
      __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
      __ mov(ebx, eax);
      __ jmp(&push_receiver);
  
      __ bind(&use_global_receiver);
      __ mov(ebx,
             Operand(esi, Context::SlotOffset(Context::GLOBAL_OBJECT_INDEX)));
      __ mov(ebx, FieldOperand(ebx, GlobalObject::kGlobalReceiverOffset));
  
      // Push the receiver.
      __ bind(&push_receiver);
      __ push(ebx);
  
      // Copy all arguments from the array to the stack.
      Label entry, loop;
      __ mov(ecx, Operand(ebp, kIndexOffset));
      __ jmp(&entry);
      __ bind(&loop);
      __ mov(edx, Operand(ebp, kArgumentsOffset));  // load arguments
  
      // Use inline caching to speed up access to arguments.
      Handle<Code> ic = masm->isolate()->builtins()->KeyedLoadIC_Initialize();
      __ call(ic, RelocInfo::CODE_TARGET);
      // It is important that we do not have a test instruction after the
      // call.  A test instruction after the call is used to indicate that
      // we have generated an inline version of the keyed load.  In this
      // case, we know that we are not generating a test instruction next.
  
      // Push the nth argument.
      __ push(eax);
  
      // Update the index on the stack and in register eax.
      __ mov(ecx, Operand(ebp, kIndexOffset));
      __ add(ecx, Immediate(1 << kSmiTagSize));
      __ mov(Operand(ebp, kIndexOffset), ecx);
  
      __ bind(&entry);
      __ cmp(ecx, Operand(ebp, kLimitOffset));
      __ j(not_equal, &loop);
  
      // Call the function.
      Label call_proxy;
      __ mov(eax, ecx);
      ParameterCount actual(eax);
      __ SmiUntag(eax);
      __ mov(edi, Operand(ebp, kFunctionOffset));
      __ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
      __ j(not_equal, &call_proxy);
      __ InvokeFunction(edi, actual, CALL_FUNCTION, NullCallWrapper());
  
      frame_scope.GenerateLeaveFrame();
      __ ret(3 * kPointerSize);  // remove this, receiver, and arguments
  
      // Call the function proxy.
      __ bind(&call_proxy);
      __ push(edi);  // add function proxy as last argument
      __ inc(eax);
      __ Set(ebx, Immediate(0));
      __ GetBuiltinEntry(edx, Builtins::CALL_FUNCTION_PROXY);
      __ call(masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),
              RelocInfo::CODE_TARGET);
  
      // Leave internal frame.
    }
    __ ret(3 * kPointerSize);  // remove this, receiver, and arguments
  }
  
  
  void Builtins::Generate_InternalArrayCode(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- eax : argc
    //  -- esp[0] : return address
    //  -- esp[4] : last argument
    // -----------------------------------
    Label generic_array_code;
  
    // Get the InternalArray function.
    __ LoadGlobalFunction(Context::INTERNAL_ARRAY_FUNCTION_INDEX, edi);
  
    if (FLAG_debug_code) {
      // Initial map for the builtin InternalArray function should be a map.
      __ mov(ebx, FieldOperand(edi, JSFunction::kPrototypeOrInitialMapOffset));
      // Will both indicate a NULL and a Smi.
      __ test(ebx, Immediate(kSmiTagMask));
      __ Assert(not_zero, kUnexpectedInitialMapForInternalArrayFunction);
      __ CmpObjectType(ebx, MAP_TYPE, ecx);
      __ Assert(equal, kUnexpectedInitialMapForInternalArrayFunction);
    }
  
    // Run the native code for the InternalArray function called as a normal
    // function.
    // tail call a stub
    InternalArrayConstructorStub stub(masm->isolate());
    __ TailCallStub(&stub);
  }
  
  
  void Builtins::Generate_ArrayCode(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- eax : argc
    //  -- esp[0] : return address
    //  -- esp[4] : last argument
    // -----------------------------------
    Label generic_array_code;
  
    // Get the Array function.
    __ LoadGlobalFunction(Context::ARRAY_FUNCTION_INDEX, edi);
  
    if (FLAG_debug_code) {
      // Initial map for the builtin Array function should be a map.
      __ mov(ebx, FieldOperand(edi, JSFunction::kPrototypeOrInitialMapOffset));
      // Will both indicate a NULL and a Smi.
      __ test(ebx, Immediate(kSmiTagMask));
      __ Assert(not_zero, kUnexpectedInitialMapForArrayFunction);
      __ CmpObjectType(ebx, MAP_TYPE, ecx);
      __ Assert(equal, kUnexpectedInitialMapForArrayFunction);
    }
  
    // Run the native code for the Array function called as a normal function.
    // tail call a stub
    __ mov(ebx, masm->isolate()->factory()->undefined_value());
    ArrayConstructorStub stub(masm->isolate());
    __ TailCallStub(&stub);
  }
  
  
  void Builtins::Generate_StringConstructCode(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- eax                 : number of arguments
    //  -- edi                 : constructor function
    //  -- esp[0]              : return address
    //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
    //  -- esp[(argc + 1) * 4] : receiver
    // -----------------------------------
    Counters* counters = masm->isolate()->counters();
    __ IncrementCounter(counters->string_ctor_calls(), 1);
  
    if (FLAG_debug_code) {
      __ LoadGlobalFunction(Context::STRING_FUNCTION_INDEX, ecx);
      __ cmp(edi, ecx);
      __ Assert(equal, kUnexpectedStringFunction);
    }
  
    // Load the first argument into eax and get rid of the rest
    // (including the receiver).
    Label no_arguments;
    __ test(eax, eax);
    __ j(zero, &no_arguments);
    __ mov(ebx, Operand(esp, eax, times_pointer_size, 0));
    __ pop(ecx);
    __ lea(esp, Operand(esp, eax, times_pointer_size, kPointerSize));
    __ push(ecx);
    __ mov(eax, ebx);
  
    // Lookup the argument in the number to string cache.
    Label not_cached, argument_is_string;
    __ LookupNumberStringCache(eax,  // Input.
                               ebx,  // Result.
                               ecx,  // Scratch 1.
                               edx,  // Scratch 2.
                               &not_cached);
    __ IncrementCounter(counters->string_ctor_cached_number(), 1);
    __ bind(&argument_is_string);
    // ----------- S t a t e -------------
    //  -- ebx    : argument converted to string
    //  -- edi    : constructor function
    //  -- esp[0] : return address
    // -----------------------------------
  
    // Allocate a JSValue and put the tagged pointer into eax.
    Label gc_required;
    __ Allocate(JSValue::kSize,
                eax,  // Result.
                ecx,  // New allocation top (we ignore it).
                no_reg,
                &gc_required,
                TAG_OBJECT);
  
    // Set the map.
    __ LoadGlobalFunctionInitialMap(edi, ecx);
    if (FLAG_debug_code) {
      __ cmpb(FieldOperand(ecx, Map::kInstanceSizeOffset),
              JSValue::kSize >> kPointerSizeLog2);
      __ Assert(equal, kUnexpectedStringWrapperInstanceSize);
      __ cmpb(FieldOperand(ecx, Map::kUnusedPropertyFieldsOffset), 0);
      __ Assert(equal, kUnexpectedUnusedPropertiesOfStringWrapper);
    }
    __ mov(FieldOperand(eax, HeapObject::kMapOffset), ecx);
  
    // Set properties and elements.
    Factory* factory = masm->isolate()->factory();
    __ Set(ecx, Immediate(factory->empty_fixed_array()));
    __ mov(FieldOperand(eax, JSObject::kPropertiesOffset), ecx);
    __ mov(FieldOperand(eax, JSObject::kElementsOffset), ecx);
  
    // Set the value.
    __ mov(FieldOperand(eax, JSValue::kValueOffset), ebx);
  
    // Ensure the object is fully initialized.
    STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
  
    // We're done. Return.
    __ ret(0);
  
    // The argument was not found in the number to string cache. Check
    // if it's a string already before calling the conversion builtin.
    Label convert_argument;
    __ bind(&not_cached);
    STATIC_ASSERT(kSmiTag == 0);
    __ JumpIfSmi(eax, &convert_argument);
    Condition is_string = masm->IsObjectStringType(eax, ebx, ecx);
    __ j(NegateCondition(is_string), &convert_argument);
    __ mov(ebx, eax);
    __ IncrementCounter(counters->string_ctor_string_value(), 1);
    __ jmp(&argument_is_string);
  
    // Invoke the conversion builtin and put the result into ebx.
    __ bind(&convert_argument);
    __ IncrementCounter(counters->string_ctor_conversions(), 1);
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      __ push(edi);  // Preserve the function.
      __ push(eax);
      __ InvokeBuiltin(Builtins::TO_STRING, CALL_FUNCTION);
      __ pop(edi);
    }
    __ mov(ebx, eax);
    __ jmp(&argument_is_string);
  
    // Load the empty string into ebx, remove the receiver from the
    // stack, and jump back to the case where the argument is a string.
    __ bind(&no_arguments);
    __ Set(ebx, Immediate(factory->empty_string()));
    __ pop(ecx);
    __ lea(esp, Operand(esp, kPointerSize));
    __ push(ecx);
    __ jmp(&argument_is_string);
  
    // At this point the argument is already a string. Call runtime to
    // create a string wrapper.
    __ bind(&gc_required);
    __ IncrementCounter(counters->string_ctor_gc_required(), 1);
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      __ push(ebx);
      __ CallRuntime(Runtime::kNewStringWrapper, 1);
    }
    __ ret(0);
  }
  
  
  static void EnterArgumentsAdaptorFrame(MacroAssembler* masm) {
    __ push(ebp);
    __ mov(ebp, esp);
  
    // Store the arguments adaptor context sentinel.
    __ push(Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
  
    // Push the function on the stack.
    __ push(edi);
  
    // Preserve the number of arguments on the stack. Must preserve eax,
    // ebx and ecx because these registers are used when copying the
    // arguments and the receiver.
    STATIC_ASSERT(kSmiTagSize == 1);
    __ lea(edi, Operand(eax, eax, times_1, kSmiTag));
    __ push(edi);
  }
  
  
  static void LeaveArgumentsAdaptorFrame(MacroAssembler* masm) {
    // Retrieve the number of arguments from the stack.
    __ mov(ebx, Operand(ebp, ArgumentsAdaptorFrameConstants::kLengthOffset));
  
    // Leave the frame.
    __ leave();
  
    // Remove caller arguments from the stack.
    STATIC_ASSERT(kSmiTagSize == 1 && kSmiTag == 0);
    __ pop(ecx);
    __ lea(esp, Operand(esp, ebx, times_2, 1 * kPointerSize));  // 1 ~ receiver
    __ push(ecx);
  }
  
  
  void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
    // ----------- S t a t e -------------
    //  -- eax : actual number of arguments
    //  -- ebx : expected number of arguments
    //  -- edi : function (passed through to callee)
    // -----------------------------------
  
    Label invoke, dont_adapt_arguments;
    __ IncrementCounter(masm->isolate()->counters()->arguments_adaptors(), 1);
  
    Label enough, too_few;
    __ mov(edx, FieldOperand(edi, JSFunction::kCodeEntryOffset));
    __ cmp(eax, ebx);
    __ j(less, &too_few);
    __ cmp(ebx, SharedFunctionInfo::kDontAdaptArgumentsSentinel);
    __ j(equal, &dont_adapt_arguments);
  
    {  // Enough parameters: Actual >= expected.
      __ bind(&enough);
      EnterArgumentsAdaptorFrame(masm);
  
      // Copy receiver and all expected arguments.
      const int offset = StandardFrameConstants::kCallerSPOffset;
      __ lea(eax, Operand(ebp, eax, times_4, offset));
      __ mov(edi, -1);  // account for receiver
  
      Label copy;
      __ bind(&copy);
      __ inc(edi);
      __ push(Operand(eax, 0));
      __ sub(eax, Immediate(kPointerSize));
      __ cmp(edi, ebx);
      __ j(less, &copy);
      __ jmp(&invoke);
    }
  
    {  // Too few parameters: Actual < expected.
      __ bind(&too_few);
      EnterArgumentsAdaptorFrame(masm);
  
      // Copy receiver and all actual arguments.
      const int offset = StandardFrameConstants::kCallerSPOffset;
      __ lea(edi, Operand(ebp, eax, times_4, offset));
      // ebx = expected - actual.
      __ sub(ebx, eax);
      // eax = -actual - 1
      __ neg(eax);
      __ sub(eax, Immediate(1));
  
      Label copy;
      __ bind(&copy);
      __ inc(eax);
      __ push(Operand(edi, 0));
      __ sub(edi, Immediate(kPointerSize));
      __ test(eax, eax);
      __ j(not_zero, &copy);
  
      // Fill remaining expected arguments with undefined values.
      Label fill;
      __ bind(&fill);
      __ inc(eax);
      __ push(Immediate(masm->isolate()->factory()->undefined_value()));
      __ cmp(eax, ebx);
      __ j(less, &fill);
    }
  
    // Call the entry point.
    __ bind(&invoke);
    // Restore function pointer.
    __ mov(edi, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
    __ call(edx);
  
    // Store offset of return address for deoptimizer.
    masm->isolate()->heap()->SetArgumentsAdaptorDeoptPCOffset(masm->pc_offset());
  
    // Leave frame and return.
    LeaveArgumentsAdaptorFrame(masm);
    __ ret(0);
  
    // -------------------------------------------
    // Dont adapt arguments.
    // -------------------------------------------
    __ bind(&dont_adapt_arguments);
    __ jmp(edx);
  }
  
  
  void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
    // Lookup the function in the JavaScript frame.
    __ mov(eax, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      // Pass function as argument.
      __ push(eax);
      __ CallRuntime(Runtime::kCompileForOnStackReplacement, 1);
    }
  
    Label skip;
    // If the code object is null, just return to the unoptimized code.
    __ cmp(eax, Immediate(0));
    __ j(not_equal, &skip, Label::kNear);
    __ ret(0);
  
    __ bind(&skip);
  
    // Load deoptimization data from the code object.
    __ mov(ebx, Operand(eax, Code::kDeoptimizationDataOffset - kHeapObjectTag));
  
    // Load the OSR entrypoint offset from the deoptimization data.
    __ mov(ebx, Operand(ebx, FixedArray::OffsetOfElementAt(
        DeoptimizationInputData::kOsrPcOffsetIndex) - kHeapObjectTag));
    __ SmiUntag(ebx);
  
    // Compute the target address = code_obj + header_size + osr_offset
    __ lea(eax, Operand(eax, ebx, times_1, Code::kHeaderSize - kHeapObjectTag));
  
    // Overwrite the return address on the stack.
    __ mov(Operand(esp, 0), eax);
  
    // And "return" to the OSR entry point of the function.
    __ ret(0);
  }
  
  
  void Builtins::Generate_OsrAfterStackCheck(MacroAssembler* masm) {
    // We check the stack limit as indicator that recompilation might be done.
    Label ok;
    ExternalReference stack_limit =
        ExternalReference::address_of_stack_limit(masm->isolate());
    __ cmp(esp, Operand::StaticVariable(stack_limit));
    __ j(above_equal, &ok, Label::kNear);
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
      __ CallRuntime(Runtime::kStackGuard, 0);
    }
    __ jmp(masm->isolate()->builtins()->OnStackReplacement(),
           RelocInfo::CODE_TARGET);
  
    __ bind(&ok);
    __ ret(0);
  }
  
  #undef __
  }
  }  // namespace v8::internal
  
  #endif  // V8_TARGET_ARCH_IA32
  