CSE2410 Fall 2014 Bounce

// 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_X64

#include "codegen.h"

#include "deoptimizer.h"

#include "full-codegen.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 -------------

  //  -- rax                 : number of arguments excluding receiver

  //  -- rdi                 : called function (only guaranteed when

  //                           extra_args requires it)

  //  -- rsi                 : context

  //  -- rsp[0]              : return address

  //  -- rsp[8]              : last argument

  //  -- ...

  //  -- rsp[8 * argc]       : first argument (argc == rax)

  //  -- rsp[8 * (argc + 1)] : receiver

  // -----------------------------------

  // Insert extra arguments.

  int num_extra_args = 0;

  if (extra_args == NEEDS_CALLED_FUNCTION) {

    num_extra_args = 1;

    __ PopReturnAddressTo(kScratchRegister);

    __ push(rdi);

    __ PushReturnAddressFrom(kScratchRegister);

  } else {

    ASSERT(extra_args == NO_EXTRA_ARGUMENTS);

  }

  // JumpToExternalReference expects rax to contain the number of arguments

  // including the receiver and the extra arguments.

  __ addq(rax, Immediate(num_extra_args + 1));

  __ JumpToExternalReference(ExternalReference(id, masm->isolate()), 1);

}

static void CallRuntimePassFunction(MacroAssembler* masm,

                                    Runtime::FunctionId function_id) {

  FrameScope scope(masm, StackFrame::INTERNAL);

  // Push a copy of the function onto the stack.

  __ push(rdi);

  // Push call kind information.

  __ push(rcx);

  // Function is also the parameter to the runtime call.

  __ push(rdi);

  __ CallRuntime(function_id, 1);

  // Restore call kind information.

  __ pop(rcx);

  // Restore receiver.

  __ pop(rdi);

}

static void GenerateTailCallToSharedCode(MacroAssembler* masm) {

  __ movq(kScratchRegister,

          FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));

  __ movq(kScratchRegister,

          FieldOperand(kScratchRegister, SharedFunctionInfo::kCodeOffset));

  __ lea(kScratchRegister, FieldOperand(kScratchRegister, Code::kHeaderSize));

  __ jmp(kScratchRegister);

}

void Builtins::Generate_InRecompileQueue(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;

  __ CompareRoot(rsp, Heap::kStackLimitRootIndex);

  __ j(above_equal, &ok);

  CallRuntimePassFunction(masm, Runtime::kTryInstallRecompiledCode);

  // Tail call to returned code.

  __ lea(rax, FieldOperand(rax, Code::kHeaderSize));

  __ jmp(rax);

  __ bind(&ok);

  GenerateTailCallToSharedCode(masm);

}

void Builtins::Generate_ConcurrentRecompile(MacroAssembler* masm) {

  CallRuntimePassFunction(masm, Runtime::kConcurrentRecompile);

  GenerateTailCallToSharedCode(masm);

}

static void Generate_JSConstructStubHelper(MacroAssembler* masm,

                                           bool is_api_function,

                                           bool count_constructions) {

  // ----------- S t a t e -------------

  //  -- rax: number of arguments

  //  -- rdi: constructor function

  // -----------------------------------

  // Should never count constructions for api objects.

  ASSERT(!is_api_function || !count_constructions);

  // Enter a construct frame.

  {

    FrameScope scope(masm, StackFrame::CONSTRUCT);

    // Store a smi-tagged arguments count on the stack.

    __ Integer32ToSmi(rax, rax);

    __ push(rax);

    // Push the function to invoke on the stack.

    __ push(rdi);

    // 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());

      __ movq(kScratchRegister, debug_step_in_fp);

      __ cmpq(Operand(kScratchRegister, 0), 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.

      // rdi: constructor

      __ movq(rax, FieldOperand(rdi, JSFunction::kPrototypeOrInitialMapOffset));

      // Will both indicate a NULL and a Smi

      ASSERT(kSmiTag == 0);

      __ JumpIfSmi(rax, &rt_call);

      // rdi: constructor

      // rax: initial map (if proven valid below)

      __ CmpObjectType(rax, MAP_TYPE, rbx);

      __ 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.

      // rdi: constructor

      // rax: initial map

      __ CmpInstanceType(rax, JS_FUNCTION_TYPE);

      __ j(equal, &rt_call);

      if (count_constructions) {

        Label allocate;

        // Decrease generous allocation count.

        __ movq(rcx, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));

        __ decb(FieldOperand(rcx,

                             SharedFunctionInfo::kConstructionCountOffset));

        __ j(not_zero, &allocate);

        __ push(rax);

        __ push(rdi);

        __ push(rdi);  // constructor

        // The call will replace the stub, so the countdown is only done once.

        __ CallRuntime(Runtime::kFinalizeInstanceSize, 1);

        __ pop(rdi);

        __ pop(rax);

        __ bind(&allocate);

      }

      // Now allocate the JSObject on the heap.

      __ movzxbq(rdi, FieldOperand(rax, Map::kInstanceSizeOffset));

      __ shl(rdi, Immediate(kPointerSizeLog2));

      // rdi: size of new object

      __ Allocate(rdi,

                  rbx,

                  rdi,

                  no_reg,

                  &rt_call,

                  NO_ALLOCATION_FLAGS);

      // Allocated the JSObject, now initialize the fields.

      // rax: initial map

      // rbx: JSObject (not HeapObject tagged - the actual address).

      // rdi: start of next object

      __ movq(Operand(rbx, JSObject::kMapOffset), rax);

      __ LoadRoot(rcx, Heap::kEmptyFixedArrayRootIndex);

      __ movq(Operand(rbx, JSObject::kPropertiesOffset), rcx);

      __ movq(Operand(rbx, JSObject::kElementsOffset), rcx);

      // Set extra fields in the newly allocated object.

      // rax: initial map

      // rbx: JSObject

      // rdi: start of next object

      __ lea(rcx, Operand(rbx, JSObject::kHeaderSize));

      __ LoadRoot(rdx, Heap::kUndefinedValueRootIndex);

      if (count_constructions) {

        __ movzxbq(rsi,

                   FieldOperand(rax, Map::kPreAllocatedPropertyFieldsOffset));

        __ lea(rsi,

               Operand(rbx, rsi, times_pointer_size, JSObject::kHeaderSize));

        // rsi: offset of first field after pre-allocated fields

        if (FLAG_debug_code) {

          __ cmpq(rsi, rdi);

          __ Assert(less_equal,

                    kUnexpectedNumberOfPreAllocatedPropertyFields);

        }

        __ InitializeFieldsWithFiller(rcx, rsi, rdx);

        __ LoadRoot(rdx, Heap::kOnePointerFillerMapRootIndex);

      }

      __ InitializeFieldsWithFiller(rcx, rdi, rdx);

      // 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.

      // rax: initial map

      // rbx: JSObject

      // rdi: start of next object

      __ or_(rbx, Immediate(kHeapObjectTag));

      // Check if a non-empty properties array is needed.

      // Allocate and initialize a FixedArray if it is.

      // rax: initial map

      // rbx: JSObject

      // rdi: start of next object

      // Calculate total properties described map.

      __ movzxbq(rdx, FieldOperand(rax, Map::kUnusedPropertyFieldsOffset));

      __ movzxbq(rcx,

                 FieldOperand(rax, Map::kPreAllocatedPropertyFieldsOffset));

      __ addq(rdx, rcx);

      // Calculate unused properties past the end of the in-object properties.

      __ movzxbq(rcx, FieldOperand(rax, Map::kInObjectPropertiesOffset));

      __ subq(rdx, rcx);

      // 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.

      // rbx: JSObject

      // rdi: start of next object (will be start of FixedArray)

      // rdx: number of elements in properties array

      __ Allocate(FixedArray::kHeaderSize,

                  times_pointer_size,

                  rdx,

                  rdi,

                  rax,

                  no_reg,

                  &undo_allocation,

                  RESULT_CONTAINS_TOP);

      // Initialize the FixedArray.

      // rbx: JSObject

      // rdi: FixedArray

      // rdx: number of elements

      // rax: start of next object

      __ LoadRoot(rcx, Heap::kFixedArrayMapRootIndex);

      __ movq(Operand(rdi, HeapObject::kMapOffset), rcx);  // setup the map

      __ Integer32ToSmi(rdx, rdx);

      __ movq(Operand(rdi, FixedArray::kLengthOffset), rdx);  // and length

      // Initialize the fields to undefined.

      // rbx: JSObject

      // rdi: FixedArray

      // rax: start of next object

      // rdx: number of elements

      { Label loop, entry;

        __ LoadRoot(rdx, Heap::kUndefinedValueRootIndex);

        __ lea(rcx, Operand(rdi, FixedArray::kHeaderSize));

        __ jmp(&entry);

        __ bind(&loop);

        __ movq(Operand(rcx, 0), rdx);

        __ addq(rcx, Immediate(kPointerSize));

        __ bind(&entry);

        __ cmpq(rcx, rax);

        __ j(below, &loop);

      }

      // Store the initialized FixedArray into the properties field of

      // the JSObject

      // rbx: JSObject

      // rdi: FixedArray

      __ or_(rdi, Immediate(kHeapObjectTag));  // add the heap tag

      __ movq(FieldOperand(rbx, JSObject::kPropertiesOffset), rdi);

      // Continue with JSObject being successfully allocated

      // rbx: 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.

      // rbx: JSObject (previous new top)

      __ bind(&undo_allocation);

      __ UndoAllocationInNewSpace(rbx);

    }

    // Allocate the new receiver object using the runtime call.

    // rdi: function (constructor)

    __ bind(&rt_call);

    // Must restore rdi (constructor) before calling runtime.

    __ movq(rdi, Operand(rsp, 0));

    __ push(rdi);

    __ CallRuntime(Runtime::kNewObject, 1);

    __ movq(rbx, rax);  // store result in rbx

    // New object allocated.

    // rbx: newly allocated object

    __ bind(&allocated);

    // Retrieve the function from the stack.

    __ pop(rdi);

    // Retrieve smi-tagged arguments count from the stack.

    __ movq(rax, Operand(rsp, 0));

    __ SmiToInteger32(rax, rax);

    // 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(rbx);

    __ push(rbx);

    // Set up pointer to last argument.

    __ lea(rbx, Operand(rbp, StandardFrameConstants::kCallerSPOffset));

    // Copy arguments and receiver to the expression stack.

    Label loop, entry;

    __ movq(rcx, rax);

    __ jmp(&entry);

    __ bind(&loop);

    __ push(Operand(rbx, rcx, times_pointer_size, 0));

    __ bind(&entry);

    __ decq(rcx);

    __ j(greater_equal, &loop);

    // Call the function.

    if (is_api_function) {

      __ movq(rsi, FieldOperand(rdi, JSFunction::kContextOffset));

      Handle<Code> code =

          masm->isolate()->builtins()->HandleApiCallConstruct();

      ParameterCount expected(0);

      __ InvokeCode(code, expected, expected, RelocInfo::CODE_TARGET,

                    CALL_FUNCTION, NullCallWrapper(), CALL_AS_METHOD);

    } else {

      ParameterCount actual(rax);

      __ InvokeFunction(rdi, actual, CALL_FUNCTION,

                        NullCallWrapper(), CALL_AS_METHOD);

    }

    // 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.

    __ movq(rsi, Operand(rbp, 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(rax, &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.

    STATIC_ASSERT(LAST_SPEC_OBJECT_TYPE == LAST_TYPE);

    __ CmpObjectType(rax, FIRST_SPEC_OBJECT_TYPE, rcx);

    __ j(above_equal, &exit);

    // Throw away the result of the constructor invocation and use the

    // on-stack receiver as the result.

    __ bind(&use_receiver);

    __ movq(rax, Operand(rsp, 0));

    // Restore the arguments count and leave the construct frame.

    __ bind(&exit);

    __ movq(rbx, Operand(rsp, kPointerSize));  // Get arguments count.

    // Leave construct frame.

  }

  // Remove caller arguments from the stack and return.

  __ PopReturnAddressTo(rcx);

  SmiIndex index = masm->SmiToIndex(rbx, rbx, kPointerSizeLog2);

  __ lea(rsp, Operand(rsp, index.reg, index.scale, 1 * kPointerSize));

  __ PushReturnAddressFrom(rcx);

  Counters* counters = masm->isolate()->counters();

  __ IncrementCounter(counters->constructed_objects(), 1);

  __ ret(0);

}

void Builtins::Generate_JSConstructStubCountdown(MacroAssembler* masm) {

  Generate_JSConstructStubHelper(masm, false, true);

}

void Builtins::Generate_JSConstructStubGeneric(MacroAssembler* masm) {

  Generate_JSConstructStubHelper(masm, false, false);

}

void Builtins::Generate_JSConstructStubApi(MacroAssembler* masm) {

  Generate_JSConstructStubHelper(masm, true, false);

}

static void Generate_JSEntryTrampolineHelper(MacroAssembler* masm,

                                             bool is_construct) {

  ProfileEntryHookStub::MaybeCallEntryHook(masm);

  // Expects five C++ function parameters.

  // - Address entry (ignored)

  // - JSFunction* function (

  // - Object* receiver

  // - int argc

  // - Object*** argv

  // (see Handle::Invoke in execution.cc).

  // Open a C++ scope for the FrameScope.

  {

    // Platform specific argument handling. After this, the stack contains

    // an internal frame and the pushed function and receiver, and

    // register rax and rbx holds the argument count and argument array,

    // while rdi holds the function pointer and rsi the context.

#ifdef _WIN64

    // MSVC parameters in:

    // rcx        : entry (ignored)

    // rdx        : function

    // r8         : receiver

    // r9         : argc

    // [rsp+0x20] : argv

    // Clear the context before we push it when entering the internal frame.

    __ Set(rsi, 0);

    // Enter an internal frame.

    FrameScope scope(masm, StackFrame::INTERNAL);

    // Load the function context into rsi.

    __ movq(rsi, FieldOperand(rdx, JSFunction::kContextOffset));

    // Push the function and the receiver onto the stack.

    __ push(rdx);

    __ push(r8);

    // Load the number of arguments and setup pointer to the arguments.

    __ movq(rax, r9);

    // Load the previous frame pointer to access C argument on stack

    __ movq(kScratchRegister, Operand(rbp, 0));

    __ movq(rbx, Operand(kScratchRegister, EntryFrameConstants::kArgvOffset));

    // Load the function pointer into rdi.

    __ movq(rdi, rdx);

#else  // _WIN64

    // GCC parameters in:

    // rdi : entry (ignored)

    // rsi : function

    // rdx : receiver

    // rcx : argc

    // r8  : argv

    __ movq(rdi, rsi);

    // rdi : function

    // Clear the context before we push it when entering the internal frame.

    __ Set(rsi, 0);

    // Enter an internal frame.

    FrameScope scope(masm, StackFrame::INTERNAL);

    // Push the function and receiver and setup the context.

    __ push(rdi);

    __ push(rdx);

    __ movq(rsi, FieldOperand(rdi, JSFunction::kContextOffset));

    // Load the number of arguments and setup pointer to the arguments.

    __ movq(rax, rcx);

    __ movq(rbx, r8);

#endif  // _WIN64

    // Current stack contents:

    // [rsp + 2 * kPointerSize ... ] : Internal frame

    // [rsp + kPointerSize]          : function

    // [rsp]                         : receiver

    // Current register contents:

    // rax : argc

    // rbx : argv

    // rsi : context

    // rdi : function

    // Copy arguments to the stack in a loop.

    // Register rbx points to array of pointers to handle locations.

    // Push the values of these handles.

    Label loop, entry;

    __ Set(rcx, 0);  // Set loop variable to 0.

    __ jmp(&entry);

    __ bind(&loop);

    __ movq(kScratchRegister, Operand(rbx, rcx, times_pointer_size, 0));

    __ push(Operand(kScratchRegister, 0));  // dereference handle

    __ addq(rcx, Immediate(1));

    __ bind(&entry);

    __ cmpq(rcx, rax);

    __ j(not_equal, &loop);

    // Invoke the code.

    if (is_construct) {

      // No type feedback cell is available

      Handle<Object> undefined_sentinel(

          masm->isolate()->factory()->undefined_value());

      __ Move(rbx, undefined_sentinel);

      // Expects rdi to hold function pointer.

      CallConstructStub stub(NO_CALL_FUNCTION_FLAGS);

      __ CallStub(&stub);

    } else {

      ParameterCount actual(rax);

      // Function must be in rdi.

      __ InvokeFunction(rdi, actual, CALL_FUNCTION,

                        NullCallWrapper(), CALL_AS_METHOD);

    }

    // Exit the internal frame. Notice that this also removes the empty

    // context and the function left on the stack by the code

    // invocation.

  }

  // TODO(X64): Is argument correct? Is there a receiver to remove?

  __ ret(1 * 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_LazyCompile(MacroAssembler* masm) {

  CallRuntimePassFunction(masm, Runtime::kLazyCompile);

  // Do a tail-call of the compiled function.

  __ lea(rax, FieldOperand(rax, Code::kHeaderSize));

  __ jmp(rax);

}

void Builtins::Generate_LazyRecompile(MacroAssembler* masm) {

  CallRuntimePassFunction(masm, Runtime::kLazyRecompile);

  // Do a tail-call of the compiled function.

  __ lea(rax, FieldOperand(rax, Code::kHeaderSize));

  __ jmp(rax);

}

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.

  __ subq(Operand(rsp, 0), Immediate(5));

  __ Pushad();

  __ movq(arg_reg_2,

          ExternalReference::isolate_address(masm->isolate()));

  __ movq(arg_reg_1, Operand(rsp, kNumSafepointRegisters * kPointerSize));

  {  // NOLINT

    FrameScope scope(masm, StackFrame::MANUAL);

    __ PrepareCallCFunction(1);

    __ CallCFunction(

        ExternalReference::get_make_code_young_function(masm->isolate()), 1);

  }

  __ 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();

  __ movq(arg_reg_2, ExternalReference::isolate_address(masm->isolate()));

  __ movq(arg_reg_1, Operand(rsp, kNumSafepointRegisters * kPointerSize));

  __ subq(arg_reg_1, Immediate(Assembler::kShortCallInstructionLength));

  {  // NOLINT

    FrameScope scope(masm, StackFrame::MANUAL);

    __ PrepareCallCFunction(1);

    __ CallCFunction(

        ExternalReference::get_mark_code_as_executed_function(masm->isolate()),

        1);

  }

  __ Popad();

  // Perform prologue operations usually performed by the young code stub.

  __ PopReturnAddressTo(kScratchRegister);

  __ push(rbp);  // Caller's frame pointer.

  __ movq(rbp, rsp);

  __ push(rsi);  // Callee's context.

  __ push(rdi);  // Callee's JS Function.

  __ PushReturnAddressFrom(kScratchRegister);

  // Jump to point after the code-age stub.

  __ ret(0);

}

void Builtins::Generate_MarkCodeAsExecutedTwice(MacroAssembler* masm) {

  GenerateMakeCodeYoungAgainCommon(masm);

}

void Builtins::Generate_NotifyStubFailure(MacroAssembler* masm) {

  // 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);

    __ Popad();

    // Tear down internal frame.

  }

  __ pop(MemOperand(rsp, 0));  // Ignore state offset

  __ ret(0);  // Return to IC Miss stub, continuation still on stack.

}

static void Generate_NotifyDeoptimizedHelper(MacroAssembler* masm,

                                             Deoptimizer::BailoutType type) {

  // Enter an internal frame.

  {

    FrameScope scope(masm, StackFrame::INTERNAL);

    // Pass the deoptimization type to the runtime system.

    __ Push(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.

  __ SmiToInteger32(kScratchRegister, Operand(rsp, kPCOnStackSize));

  // Switch on the state.

  Label not_no_registers, not_tos_rax;

  __ cmpq(kScratchRegister, Immediate(FullCodeGenerator::NO_REGISTERS));

  __ j(not_equal, &not_no_registers, Label::kNear);

  __ ret(1 * kPointerSize);  // Remove state.

  __ bind(&not_no_registers);

  __ movq(rax, Operand(rsp, kPCOnStackSize + kPointerSize));

  __ cmpq(kScratchRegister, Immediate(FullCodeGenerator::TOS_REG));

  __ j(not_equal, &not_tos_rax, Label::kNear);

  __ ret(2 * kPointerSize);  // Remove state, rax.

  __ bind(&not_tos_rax);

  __ 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) {

  // Stack Layout:

  // rsp[0]           : Return address

  // rsp[8]           : Argument n

  // rsp[16]          : Argument n-1

  //  ...

  // rsp[8 * n]       : Argument 1

  // rsp[8 * (n + 1)] : Receiver (function to call)

  //

  // rax contains the number of arguments, n, not counting the receiver.

  //

  // 1. Make sure we have at least one argument.

  { Label done;

    __ testq(rax, rax);

    __ j(not_zero, &done);

    __ PopReturnAddressTo(rbx);

    __ Push(masm->isolate()->factory()->undefined_value());

    __ PushReturnAddressFrom(rbx);

    __ incq(rax);

    __ bind(&done);

  }

  // 2. Get the function to call (passed as receiver) from the stack, check

  //    if it is a function.

  Label slow, non_function;

  StackArgumentsAccessor args(rsp, rax);

  __ movq(rdi, args.GetReceiverOperand());

  __ JumpIfSmi(rdi, &non_function);

  __ CmpObjectType(rdi, JS_FUNCTION_TYPE, rcx);

  __ j(not_equal, &slow);

  // 3a. Patch the first argument if necessary when calling a function.

  Label shift_arguments;

  __ Set(rdx, 0);  // indicate regular JS_FUNCTION

  { Label convert_to_object, use_global_receiver, patch_receiver;

    // Change context eagerly in case we need the global receiver.

    __ movq(rsi, FieldOperand(rdi, JSFunction::kContextOffset));

    // Do not transform the receiver for strict mode functions.

    __ movq(rbx, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));

    __ testb(FieldOperand(rbx, SharedFunctionInfo::kStrictModeByteOffset),

             Immediate(1 << SharedFunctionInfo::kStrictModeBitWithinByte));

    __ j(not_equal, &shift_arguments);

    // Do not transform the receiver for natives.

    // SharedFunctionInfo is already loaded into rbx.

    __ testb(FieldOperand(rbx, SharedFunctionInfo::kNativeByteOffset),

             Immediate(1 << SharedFunctionInfo::kNativeBitWithinByte));

    __ j(not_zero, &shift_arguments);

    // Compute the receiver in non-strict mode.

    __ movq(rbx, args.GetArgumentOperand(1));

    __ JumpIfSmi(rbx, &convert_to_object, Label::kNear);

    __ CompareRoot(rbx, Heap::kNullValueRootIndex);

    __ j(equal, &use_global_receiver);

    __ CompareRoot(rbx, Heap::kUndefinedValueRootIndex);

    __ j(equal, &use_global_receiver);

    STATIC_ASSERT(LAST_SPEC_OBJECT_TYPE == LAST_TYPE);

    __ CmpObjectType(rbx, FIRST_SPEC_OBJECT_TYPE, rcx);

    __ j(above_equal, &shift_arguments);

    __ bind(&convert_to_object);

    {

      // Enter an internal frame in order to preserve argument count.

      FrameScope scope(masm, StackFrame::INTERNAL);

      __ Integer32ToSmi(rax, rax);

      __ push(rax);

      __ push(rbx);

      __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);

      __ movq(rbx, rax);

      __ Set(rdx, 0);  // indicate regular JS_FUNCTION

      __ pop(rax);

      __ SmiToInteger32(rax, rax);

    }

    // Restore the function to rdi.

    __ movq(rdi, args.GetReceiverOperand());

    __ jmp(&patch_receiver, Label::kNear);

    // Use the global receiver object from the called function as the

    // receiver.

    __ bind(&use_global_receiver);

    const int kGlobalIndex =

        Context::kHeaderSize + Context::GLOBAL_OBJECT_INDEX * kPointerSize;

    __ movq(rbx, FieldOperand(rsi, kGlobalIndex));

    __ movq(rbx, FieldOperand(rbx, GlobalObject::kNativeContextOffset));

    __ movq(rbx, FieldOperand(rbx, kGlobalIndex));

    __ movq(rbx, FieldOperand(rbx, GlobalObject::kGlobalReceiverOffset));

    __ bind(&patch_receiver);

    __ movq(args.GetArgumentOperand(1), rbx);

    __ jmp(&shift_arguments);

  }

  // 3b. Check for function proxy.

  __ bind(&slow);

  __ Set(rdx, 1);  // indicate function proxy

  __ CmpInstanceType(rcx, JS_FUNCTION_PROXY_TYPE);

  __ j(equal, &shift_arguments);

  __ bind(&non_function);

  __ Set(rdx, 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.

  __ movq(args.GetArgumentOperand(1), rdi);

  // 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;

    __ movq(rcx, rax);

    __ bind(&loop);

    __ movq(rbx, Operand(rsp, rcx, times_pointer_size, 0));

    __ movq(Operand(rsp, rcx, times_pointer_size, 1 * kPointerSize), rbx);

    __ decq(rcx);

    __ j(not_sign, &loop);  // While non-negative (to copy return address).

    __ pop(rbx);  // Discard copy of return address.

    __ decq(rax);  // 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;

    __ testq(rdx, rdx);

    __ j(zero, &function);

    __ Set(rbx, 0);

    __ SetCallKind(rcx, CALL_AS_METHOD);

    __ cmpq(rdx, Immediate(1));

    __ j(not_equal, &non_proxy);

    __ PopReturnAddressTo(rdx);

    __ push(rdi);  // re-add proxy object as additional argument

    __ PushReturnAddressFrom(rdx);

    __ incq(rax);

    __ GetBuiltinEntry(rdx, Builtins::CALL_FUNCTION_PROXY);

    __ jmp(masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),

           RelocInfo::CODE_TARGET);

    __ bind(&non_proxy);

    __ GetBuiltinEntry(rdx, Builtins::CALL_NON_FUNCTION);

    __ Jump(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.

  __ movq(rdx, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));

  __ movsxlq(rbx,

             FieldOperand(rdx,

                          SharedFunctionInfo::kFormalParameterCountOffset));

  __ movq(rdx, FieldOperand(rdi, JSFunction::kCodeEntryOffset));

  __ SetCallKind(rcx, CALL_AS_METHOD);

  __ cmpq(rax, rbx);

  __ j(not_equal,

       masm->isolate()->builtins()->ArgumentsAdaptorTrampoline(),

       RelocInfo::CODE_TARGET);

  ParameterCount expected(0);

  __ InvokeCode(rdx, expected, expected, JUMP_FUNCTION,

                NullCallWrapper(), CALL_AS_METHOD);

}

void Builtins::Generate_FunctionApply(MacroAssembler* masm) {

  // Stack at entry:

  // rsp     : return address

  // rsp[8]  : arguments

  // rsp[16] : receiver ("this")

  // rsp[24] : function

  {

    FrameScope frame_scope(masm, StackFrame::INTERNAL);

    // Stack frame:

    // rbp     : Old base pointer

    // rbp[8]  : return address

    // rbp[16] : function arguments

    // rbp[24] : receiver

    // rbp[32] : function

    static const int kArgumentsOffset = kFPOnStackSize + kPCOnStackSize;

    static const int kReceiverOffset = kArgumentsOffset + kPointerSize;

    static const int kFunctionOffset = kReceiverOffset + kPointerSize;

    __ push(Operand(rbp, kFunctionOffset));

    __ push(Operand(rbp, kArgumentsOffset));

    __ 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;

    __ LoadRoot(kScratchRegister, Heap::kRealStackLimitRootIndex);

    __ movq(rcx, rsp);

    // Make rcx the space we have left. The stack might already be overflowed

    // here which will cause rcx to become negative.

    __ subq(rcx, kScratchRegister);

    // Make rdx the space we need for the array when it is unrolled onto the

    // stack.

    __ PositiveSmiTimesPowerOfTwoToInteger64(rdx, rax, kPointerSizeLog2);

    // Check if the arguments will overflow the stack.

    __ cmpq(rcx, rdx);

    __ j(greater, &okay);  // Signed comparison.

    // Out of stack space.

    __ push(Operand(rbp, kFunctionOffset));

    __ push(rax);

    __ 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(rax);  // limit

    __ push(Immediate(0));  // index

    // Get the receiver.

    __ movq(rbx, Operand(rbp, kReceiverOffset));

    // Check that the function is a JS function (otherwise it must be a proxy).

    Label push_receiver;

    __ movq(rdi, Operand(rbp, kFunctionOffset));

    __ CmpObjectType(rdi, JS_FUNCTION_TYPE, rcx);

    __ j(not_equal, &push_receiver);

    // Change context eagerly to get the right global object if necessary.

    __ movq(rsi, FieldOperand(rdi, JSFunction::kContextOffset));

    // Do not transform the receiver for strict mode functions.

    Label call_to_object, use_global_receiver;

    __ movq(rdx, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));

    __ testb(FieldOperand(rdx, SharedFunctionInfo::kStrictModeByteOffset),

             Immediate(1 << SharedFunctionInfo::kStrictModeBitWithinByte));

    __ j(not_equal, &push_receiver);

    // Do not transform the receiver for natives.

    __ testb(FieldOperand(rdx, SharedFunctionInfo::kNativeByteOffset),

             Immediate(1 << SharedFunctionInfo::kNativeBitWithinByte));

    __ j(not_equal, &push_receiver);

    // Compute the receiver in non-strict mode.

    __ JumpIfSmi(rbx, &call_to_object, Label::kNear);

    __ CompareRoot(rbx, Heap::kNullValueRootIndex);

    __ j(equal, &use_global_receiver);

    __ CompareRoot(rbx, Heap::kUndefinedValueRootIndex);

    __ j(equal, &use_global_receiver);

    // If given receiver is already a JavaScript object then there's no

    // reason for converting it.

    STATIC_ASSERT(LAST_SPEC_OBJECT_TYPE == LAST_TYPE);

    __ CmpObjectType(rbx, FIRST_SPEC_OBJECT_TYPE, rcx);

    __ j(above_equal, &push_receiver);

    // Convert the receiver to an object.

    __ bind(&call_to_object);

    __ push(rbx);

    __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);

    __ movq(rbx, rax);

    __ jmp(&push_receiver, Label::kNear);

    // Use the current global receiver object as the receiver.

    __ bind(&use_global_receiver);

    const int kGlobalOffset =

        Context::kHeaderSize + Context::GLOBAL_OBJECT_INDEX * kPointerSize;

    __ movq(rbx, FieldOperand(rsi, kGlobalOffset));

    __ movq(rbx, FieldOperand(rbx, GlobalObject::kNativeContextOffset));

    __ movq(rbx, FieldOperand(rbx, kGlobalOffset));

    __ movq(rbx, FieldOperand(rbx, GlobalObject::kGlobalReceiverOffset));

    // Push the receiver.

    __ bind(&push_receiver);

    __ push(rbx);

    // Copy all arguments from the array to the stack.

    Label entry, loop;

    __ movq(rax, Operand(rbp, kIndexOffset));

    __ jmp(&entry);

    __ bind(&loop);

    __ movq(rdx, Operand(rbp, 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(rax);

    // Update the index on the stack and in register rax.

    __ movq(rax, Operand(rbp, kIndexOffset));

    __ SmiAddConstant(rax, rax, Smi::FromInt(1));

    __ movq(Operand(rbp, kIndexOffset), rax);

    __ bind(&entry);

    __ cmpq(rax, Operand(rbp, kLimitOffset));

    __ j(not_equal, &loop);

    // Invoke the function.

    Label call_proxy;

    ParameterCount actual(rax);

    __ SmiToInteger32(rax, rax);

    __ movq(rdi, Operand(rbp, kFunctionOffset));

    __ CmpObjectType(rdi, JS_FUNCTION_TYPE, rcx);

    __ j(not_equal, &call_proxy);

    __ InvokeFunction(rdi, actual, CALL_FUNCTION,

                      NullCallWrapper(), CALL_AS_METHOD);

    frame_scope.GenerateLeaveFrame();

    __ ret(3 * kPointerSize);  // remove this, receiver, and arguments

    // Invoke the function proxy.

    __ bind(&call_proxy);

    __ push(rdi);  // add function proxy as last argument

    __ incq(rax);

    __ Set(rbx, 0);

    __ SetCallKind(rcx, CALL_AS_METHOD);

    __ GetBuiltinEntry(rdx, 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 -------------

  //  -- rax    : argc

  //  -- rsp[0] : return address

  //  -- rsp[8] : last argument

  // -----------------------------------

  Label generic_array_code;

  // Get the InternalArray function.

  __ LoadGlobalFunction(Context::INTERNAL_ARRAY_FUNCTION_INDEX, rdi);

  if (FLAG_debug_code) {

    // Initial map for the builtin InternalArray functions should be maps.

    __ movq(rbx, FieldOperand(rdi, JSFunction::kPrototypeOrInitialMapOffset));

    // Will both indicate a NULL and a Smi.

    STATIC_ASSERT(kSmiTag == 0);

    Condition not_smi = NegateCondition(masm->CheckSmi(rbx));

    __ Check(not_smi, kUnexpectedInitialMapForInternalArrayFunction);

    __ CmpObjectType(rbx, MAP_TYPE, rcx);

    __ Check(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 -------------

  //  -- rax    : argc

  //  -- rsp[0] : return address

  //  -- rsp[8] : last argument

  // -----------------------------------

  Label generic_array_code;

  // Get the Array function.

  __ LoadGlobalFunction(Context::ARRAY_FUNCTION_INDEX, rdi);

  if (FLAG_debug_code) {

    // Initial map for the builtin Array functions should be maps.

    __ movq(rbx, FieldOperand(rdi, JSFunction::kPrototypeOrInitialMapOffset));

    // Will both indicate a NULL and a Smi.

    STATIC_ASSERT(kSmiTag == 0);

    Condition not_smi = NegateCondition(masm->CheckSmi(rbx));

    __ Check(not_smi, kUnexpectedInitialMapForArrayFunction);

    __ CmpObjectType(rbx, MAP_TYPE, rcx);

    __ Check(equal, kUnexpectedInitialMapForArrayFunction);

  }

  // Run the native code for the Array function called as a normal function.

  // tail call a stub

  Handle<Object> undefined_sentinel(

      masm->isolate()->heap()->undefined_value(),

      masm->isolate());

  __ Move(rbx, undefined_sentinel);

  ArrayConstructorStub stub(masm->isolate());

  __ TailCallStub(&stub);

}

void Builtins::Generate_StringConstructCode(MacroAssembler* masm) {

  // ----------- S t a t e -------------

  //  -- rax                 : number of arguments

  //  -- rdi                 : constructor function

  //  -- rsp[0]              : return address

  //  -- rsp[(argc - n) * 8] : arg[n] (zero-based)

  //  -- rsp[(argc + 1) * 8] : receiver

  // -----------------------------------

  Counters* counters = masm->isolate()->counters();

  __ IncrementCounter(counters->string_ctor_calls(), 1);

  if (FLAG_debug_code) {

    __ LoadGlobalFunction(Context::STRING_FUNCTION_INDEX, rcx);

    __ cmpq(rdi, rcx);

    __ Assert(equal, kUnexpectedStringFunction);

  }

  // Load the first argument into rax and get rid of the rest

  // (including the receiver).

  StackArgumentsAccessor args(rsp, rax);

  Label no_arguments;

  __ testq(rax, rax);

  __ j(zero, &no_arguments);

  __ movq(rbx, args.GetArgumentOperand(1));

  __ PopReturnAddressTo(rcx);

  __ lea(rsp, Operand(rsp, rax, times_pointer_size, kPointerSize));

  __ PushReturnAddressFrom(rcx);

  __ movq(rax, rbx);

  // Lookup the argument in the number to string cache.

  Label not_cached, argument_is_string;

  __ LookupNumberStringCache(rax,  // Input.

                             rbx,  // Result.

                             rcx,  // Scratch 1.

                             rdx,  // Scratch 2.

                             &not_cached);

  __ IncrementCounter(counters->string_ctor_cached_number(), 1);

  __ bind(&argument_is_string);

  // ----------- S t a t e -------------

  //  -- rbx    : argument converted to string

  //  -- rdi    : constructor function

  //  -- rsp[0] : return address

  // -----------------------------------

  // Allocate a JSValue and put the tagged pointer into rax.

  Label gc_required;

  __ Allocate(JSValue::kSize,

              rax,  // Result.

              rcx,  // New allocation top (we ignore it).

              no_reg,

              &gc_required,

              TAG_OBJECT);

  // Set the map.

  __ LoadGlobalFunctionInitialMap(rdi, rcx);

  if (FLAG_debug_code) {

    __ cmpb(FieldOperand(rcx, Map::kInstanceSizeOffset),

            Immediate(JSValue::kSize >> kPointerSizeLog2));

    __ Assert(equal, kUnexpectedStringWrapperInstanceSize);

    __ cmpb(FieldOperand(rcx, Map::kUnusedPropertyFieldsOffset), Immediate(0));

    __ Assert(equal, kUnexpectedUnusedPropertiesOfStringWrapper);

  }

  __ movq(FieldOperand(rax, HeapObject::kMapOffset), rcx);

  // Set properties and elements.

  __ LoadRoot(rcx, Heap::kEmptyFixedArrayRootIndex);

  __ movq(FieldOperand(rax, JSObject::kPropertiesOffset), rcx);

  __ movq(FieldOperand(rax, JSObject::kElementsOffset), rcx);

  // Set the value.

  __ movq(FieldOperand(rax, JSValue::kValueOffset), rbx);

  // 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(rax, &convert_argument);

  Condition is_string = masm->IsObjectStringType(rax, rbx, rcx);

  __ j(NegateCondition(is_string), &convert_argument);

  __ movq(rbx, rax);

  __ IncrementCounter(counters->string_ctor_string_value(), 1);

  __ jmp(&argument_is_string);

  // Invoke the conversion builtin and put the result into rbx.

  __ bind(&convert_argument);

  __ IncrementCounter(counters->string_ctor_conversions(), 1);

  {

    FrameScope scope(masm, StackFrame::INTERNAL);

    __ push(rdi);  // Preserve the function.

    __ push(rax);

    __ InvokeBuiltin(Builtins::TO_STRING, CALL_FUNCTION);

    __ pop(rdi);

  }

  __ movq(rbx, rax);

  __ jmp(&argument_is_string);

  // Load the empty string into rbx, remove the receiver from the

  // stack, and jump back to the case where the argument is a string.

  __ bind(&no_arguments);

  __ LoadRoot(rbx, Heap::kempty_stringRootIndex);

  __ PopReturnAddressTo(rcx);

  __ lea(rsp, Operand(rsp, kPointerSize));

  __ PushReturnAddressFrom(rcx);

  __ 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(rbx);

    __ CallRuntime(Runtime::kNewStringWrapper, 1);

  }

  __ ret(0);

}

static void EnterArgumentsAdaptorFrame(MacroAssembler* masm) {

  __ push(rbp);

  __ movq(rbp, rsp);

  // Store the arguments adaptor context sentinel.

  __ Push(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR));

  // Push the function on the stack.

  __ push(rdi);

  // Preserve the number of arguments on the stack. Must preserve rax,

  // rbx and rcx because these registers are used when copying the

  // arguments and the receiver.

  __ Integer32ToSmi(r8, rax);

  __ push(r8);

}

static void LeaveArgumentsAdaptorFrame(MacroAssembler* masm) {

  // Retrieve the number of arguments from the stack. Number is a Smi.

  __ movq(rbx, Operand(rbp, ArgumentsAdaptorFrameConstants::kLengthOffset));

  // Leave the frame.

  __ movq(rsp, rbp);

  __ pop(rbp);

  // Remove caller arguments from the stack.

  __ PopReturnAddressTo(rcx);

  SmiIndex index = masm->SmiToIndex(rbx, rbx, kPointerSizeLog2);

  __ lea(rsp, Operand(rsp, index.reg, index.scale, 1 * kPointerSize));

  __ PushReturnAddressFrom(rcx);

}

void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {

  // ----------- S t a t e -------------

  //  -- rax : actual number of arguments

  //  -- rbx : expected number of arguments

  //  -- rcx : call kind information

  //  -- rdx : code entry to call

  // -----------------------------------

  Label invoke, dont_adapt_arguments;

  Counters* counters = masm->isolate()->counters();

  __ IncrementCounter(counters->arguments_adaptors(), 1);

  Label enough, too_few;

  __ cmpq(rax, rbx);

  __ j(less, &too_few);

  __ cmpq(rbx, Immediate(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(rax, Operand(rbp, rax, times_pointer_size, offset));

    __ Set(r8, -1);  // account for receiver

    Label copy;

    __ bind(&copy);

    __ incq(r8);

    __ push(Operand(rax, 0));

    __ subq(rax, Immediate(kPointerSize));

    __ cmpq(r8, rbx);

    __ 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(rdi, Operand(rbp, rax, times_pointer_size, offset));

    __ Set(r8, -1);  // account for receiver

    Label copy;

    __ bind(&copy);

    __ incq(r8);

    __ push(Operand(rdi, 0));

    __ subq(rdi, Immediate(kPointerSize));

    __ cmpq(r8, rax);

    __ j(less, &copy);

    // Fill remaining expected arguments with undefined values.

    Label fill;

    __ LoadRoot(kScratchRegister, Heap::kUndefinedValueRootIndex);

    __ bind(&fill);

    __ incq(r8);

    __ push(kScratchRegister);

    __ cmpq(r8, rbx);

    __ j(less, &fill);

    // Restore function pointer.

    __ movq(rdi, Operand(rbp, JavaScriptFrameConstants::kFunctionOffset));

  }

  // Call the entry point.

  __ bind(&invoke);

  __ call(rdx);

  // 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(rdx);

}

void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {

  // Lookup the function in the JavaScript frame.

  __ movq(rax, Operand(rbp, JavaScriptFrameConstants::kFunctionOffset));

  {

    FrameScope scope(masm, StackFrame::INTERNAL);

    // Lookup and calculate pc offset.

    __ movq(rdx, Operand(rbp, StandardFrameConstants::kCallerPCOffset));

    __ movq(rbx, FieldOperand(rax, JSFunction::kSharedFunctionInfoOffset));

    __ subq(rdx, Immediate(Code::kHeaderSize - kHeapObjectTag));

    __ subq(rdx, FieldOperand(rbx, SharedFunctionInfo::kCodeOffset));

    __ Integer32ToSmi(rdx, rdx);

    // Pass both function and pc offset as arguments.

    __ push(rax);

    __ push(rdx);

    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 2);

  }

  Label skip;

  // If the code object is null, just return to the unoptimized code.

  __ cmpq(rax, Immediate(0));

  __ j(not_equal, &skip, Label::kNear);

  __ ret(0);

  __ bind(&skip);

  // Load deoptimization data from the code object.

  __ movq(rbx, Operand(rax, Code::kDeoptimizationDataOffset - kHeapObjectTag));

  // Load the OSR entrypoint offset from the deoptimization data.

  __ SmiToInteger32(rbx, Operand(rbx, FixedArray::OffsetOfElementAt(

      DeoptimizationInputData::kOsrPcOffsetIndex) - kHeapObjectTag));

  // Compute the target address = code_obj + header_size + osr_offset

  __ lea(rax, Operand(rax, rbx, times_1, Code::kHeaderSize - kHeapObjectTag));

  // Overwrite the return address on the stack.

  __ movq(Operand(rsp, 0), rax);

  // 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;

  __ CompareRoot(rsp, Heap::kStackLimitRootIndex);

  __ j(above_equal, &ok);

  {

    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_X64