Add test_b(Operand, immediate) to ia32 assembler, and use it where possible. ...

src/ia32/stub-cache-ia32.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1502 matching lines @@
         __ mov(Operand(esp, (argc + 1) * kPointerSize), edx);
       }
       break;
 
     case STRING_CHECK:
       if (!function->IsBuiltin()) {
         // Calling non-builtins with a value as receiver requires boxing.
         __ jmp(&miss);
       } else {
         // Check that the object is a string or a symbol.
-        __ mov(eax, FieldOperand(edx, HeapObject::kMapOffset));
-        __ movzx_b(eax, FieldOperand(eax, Map::kInstanceTypeOffset));
-        __ cmp(eax, FIRST_NONSTRING_TYPE);
+        __ CmpObjectType(edx, FIRST_NONSTRING_TYPE, eax);
         __ j(above_equal, &miss, not_taken);
         // Check that the maps starting from the prototype haven't changed.
         GenerateLoadGlobalFunctionPrototype(masm(),
                                             Context::STRING_FUNCTION_INDEX,
                                             eax);
         CheckPrototypes(JSObject::cast(object->GetPrototype()), eax, holder,
                         ebx, edx, name, &miss);
       }
       break;
 
@@ skipping 935 matching lines @@
   // Return the generated code.
   return GetCode();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32