X87: [runtime] Add %ToString and %_ToString and remove the TO_STRING 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/base/bits.h"
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
@@ skipping 2967 matching lines @@
   __ Ret();
   __ bind(&not_oddball);
 
   __ pop(ecx);   // Pop return address.
   __ push(eax);  // Push argument.
   __ push(ecx);  // Push return address.
   __ TailCallRuntime(Runtime::kToNumber, 1, 1);
 }
 
 
+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, 1, 1);
+}
+
+
 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;
   __ mov(length, FieldOperand(left, String::kLengthOffset));
@@ skipping 2218 matching lines @@
                            Operand(ebp, 7 * kPointerSize), NULL);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87