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

src/ia32/macro-assembler-ia32.h

 // 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
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   // Check if the object in register heap_object is a string. Afterwards the
   // register map contains the object map and the register instance_type
   // contains the instance_type. The registers map and instance_type can be the
   // same in which case it contains the instance type afterwards. Either of the
   // registers map and instance_type can be the same as heap_object.
   Condition IsObjectStringType(Register heap_object,
                                Register map,
                                Register instance_type);
 
+  // Check if a heap object's type is in the JSObject range, not including
+  // JSFunction.  The object's map will be loaded in the map register.
+  // Any or all of the three registers may be the same.
+  // The contents of the scratch register will always be overwritten.
+  void IsObjectJSObjectType(Register heap_object,
+                            Register map,
+                            Register scratch,
+                            Label* fail);
+
+  // The contents of the scratch register will be overwritten.
+  void IsInstanceJSObjectType(Register map, Register scratch, Label* fail);
+
   // FCmp is similar to integer cmp, but requires unsigned
   // jcc instructions (je, ja, jae, jb, jbe, je, and jz).
   void FCmp();
 
   // Smi tagging support.
   void SmiTag(Register reg) {
     ASSERT(kSmiTag == 0);
     ASSERT(kSmiTagSize == 1);
     add(reg, Operand(reg));
   }
@@ skipping 395 matching lines @@
   }                                                                       \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_IA32_MACRO_ASSEMBLER_IA32_H_