X87: [runtime] Introduce FastNewStrictArgumentsStub to optimize strict arguments.

src/x87/builtins-x87.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_X87
 
 #include "src/code-factory.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 1865 matching lines @@
       __ CallRuntime(Runtime::kCreateListFromArrayLike);
       __ Pop(edx);
       __ Pop(edi);
       __ mov(ebx, FieldOperand(eax, FixedArray::kLengthOffset));
       __ SmiUntag(ebx);
     }
     __ jmp(&done_create);
 
     // Try to create the list from an arguments object.
     __ bind(&create_arguments);
-    __ mov(ebx,
-           FieldOperand(eax, JSObject::kHeaderSize +
-                                 Heap::kArgumentsLengthIndex * kPointerSize));
+    __ mov(ebx, FieldOperand(eax, JSArgumentsObject::kLengthOffset));
     __ mov(ecx, FieldOperand(eax, JSObject::kElementsOffset));
     __ cmp(ebx, FieldOperand(ecx, FixedArray::kLengthOffset));
     __ j(not_equal, &create_runtime);
     __ SmiUntag(ebx);
     __ mov(eax, ecx);
     __ jmp(&done_create);
 
     // Try to create the list from a JSArray object.
     __ bind(&create_array);
     __ mov(ecx, FieldOperand(ecx, Map::kBitField2Offset));
@@ skipping 899 matching lines @@
 
   __ bind(&ok);
   __ ret(0);
 }
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87