[stubs] replaced ToString MacroAssembler Stub with CodeStubAssembler builtin

src/x87/code-stubs-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-stubs.h"
 #include "src/api-arguments.h"
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 2110 matching lines @@
   // ebx: instance type
   // ecx: sub string length (smi)
   // edx: from index (smi)
   StringCharAtGenerator generator(eax, edx, ecx, eax, &runtime, &runtime,
                                   &runtime, RECEIVER_IS_STRING);
   generator.GenerateFast(masm);
   __ ret(3 * kPointerSize);
   generator.SkipSlow(masm, &runtime);
 }
 
-void ToStringStub::Generate(MacroAssembler* masm) {
-  // The ToString stub takes one argument in eax.
-  Label is_number;
-  __ JumpIfSmi(eax, &is_number, Label::kNear);
-
-  Label not_string;
-  __ CmpObjectType(eax, FIRST_NONSTRING_TYPE, edi);
-  // eax: receiver
-  // edi: receiver map
-  __ j(above_equal, &not_string, Label::kNear);
-  __ Ret();
-  __ bind(&not_string);
-
-  Label not_heap_number;
-  __ CompareMap(eax, masm->isolate()->factory()->heap_number_map());
-  __ j(not_equal, &not_heap_number, Label::kNear);
-  __ bind(&is_number);
-  NumberToStringStub stub(isolate());
-  __ TailCallStub(&stub);
-  __ bind(&not_heap_number);
-
-  Label not_oddball;
-  __ CmpInstanceType(edi, ODDBALL_TYPE);
-  __ j(not_equal, &not_oddball, Label::kNear);
-  __ mov(eax, FieldOperand(eax, Oddball::kToStringOffset));
-  __ Ret();
-  __ bind(&not_oddball);
-
-  __ pop(ecx);   // Pop return address.
-  __ push(eax);  // Push argument.
-  __ push(ecx);  // Push return address.
-  __ TailCallRuntime(Runtime::kToString);
-}
-
 
 void StringHelper::GenerateFlatOneByteStringEquals(MacroAssembler* masm,
                                                    Register left,
                                                    Register right,
                                                    Register scratch1,
                                                    Register scratch2) {
   Register length = scratch1;
 
   // Compare lengths.
   Label strings_not_equal, check_zero_length;
@@ skipping 3086 matching lines @@
                            kStackUnwindSpace, nullptr, return_value_operand,
                            NULL);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87