X87: [runtime] Add %ToString and %_ToString and remove the TO_STRING builtin.

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 1509 matching lines @@
   __ mov(ebx, eax);
   __ IncrementCounter(counters->string_ctor_string_value(), 1);
   __ jmp(&argument_is_string);
 
   // Invoke the conversion builtin and put the result into ebx.
   __ bind(&convert_argument);
   __ IncrementCounter(counters->string_ctor_conversions(), 1);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
     __ push(edi);  // Preserve the function.
-    __ push(eax);
-    __ InvokeBuiltin(Context::TO_STRING_BUILTIN_INDEX, CALL_FUNCTION);
+    ToStringStub stub(masm->isolate());
+    __ CallStub(&stub);
     __ pop(edi);
   }
   __ mov(ebx, eax);
   __ jmp(&argument_is_string);
 
   // Load the empty string into ebx, remove the receiver from the
   // stack, and jump back to the case where the argument is a string.
   __ bind(&no_arguments);
   __ Move(ebx, Immediate(factory->empty_string()));
   __ pop(ecx);
@@ skipping 247 matching lines @@
 
   __ bind(&ok);
   __ ret(0);
 }
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87