[es6] re-implement rest parameters via desugaring

src/x64/code-stubs-x64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
@@ skipping 822 matching lines @@
   __ SmiToInteger64(rcx, rcx);
   __ leap(rdx, Operand(rdx, rcx, times_pointer_size,
               StandardFrameConstants::kCallerSPOffset));
   __ movp(args.GetArgumentOperand(1), rdx);
 
   __ bind(&runtime);
   __ TailCallRuntime(Runtime::kNewSloppyArguments, 3, 1);
 }
 
 
-void RestParamAccessStub::GenerateNew(MacroAssembler* masm) {
-  // rsp[0]  : return address
-  // rsp[8]  : language mode
-  // rsp[16] : index of rest parameter
-  // rsp[24] : number of parameters
-  // rsp[32] : receiver displacement
-
-  // Check if the calling frame is an arguments adaptor frame.
-  Label runtime;
-  __ movp(rdx, Operand(rbp, StandardFrameConstants::kCallerFPOffset));
-  __ movp(rcx, Operand(rdx, StandardFrameConstants::kContextOffset));
-  __ Cmp(rcx, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR));
-  __ j(not_equal, &runtime);
-
-  // Patch the arguments.length and the parameters pointer.
-  StackArgumentsAccessor args(rsp, 4, ARGUMENTS_DONT_CONTAIN_RECEIVER);
-  __ movp(rcx, Operand(rdx, ArgumentsAdaptorFrameConstants::kLengthOffset));
-  __ movp(args.GetArgumentOperand(1), rcx);
-  __ SmiToInteger64(rcx, rcx);
-  __ leap(rdx, Operand(rdx, rcx, times_pointer_size,
-                       StandardFrameConstants::kCallerSPOffset));
-  __ movp(args.GetArgumentOperand(0), rdx);
-
-  __ bind(&runtime);
-  __ TailCallRuntime(Runtime::kNewRestParam, 4, 1);
-}
-
-
 void LoadIndexedInterceptorStub::Generate(MacroAssembler* masm) {
   // Return address is on the stack.
   Label slow;
 
   Register receiver = LoadDescriptor::ReceiverRegister();
   Register key = LoadDescriptor::NameRegister();
   Register scratch = rax;
   DCHECK(!scratch.is(receiver) && !scratch.is(key));
 
   // Check that the key is an array index, that is Uint32.
@@ skipping 4551 matching lines @@
                            kStackSpace, nullptr, return_value_operand, NULL);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64