Fix VirtualFrame::is_used for ARM

src/virtual-frame-arm.h

 // Copyright 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 67 matching lines @@
 
   int register_index(Register reg) {
     return register_locations_[reg.code()];
   }
 
   bool is_used(int reg_code) {
     return register_locations_[reg_code] != kIllegalIndex;
   }
 
   bool is_used(Register reg) {
-    return is_used(reg.code()) != kIllegalIndex;
+    return is_used(reg.code());
   }
 
   // Add extra in-memory elements to the top of the frame to match an actual
   // frame (eg, the frame after an exception handler is pushed).  No code is
   // emitted.
   void Adjust(int count);
 
   // Forget elements from the top of the frame to match an actual frame (eg,
   // the frame after a runtime call).  No code is emitted.
   void Forget(int count);
@@ skipping 372 matching lines @@
 
   bool Equals(VirtualFrame* other);
 
   friend class JumpTarget;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_VIRTUAL_FRAME_ARM_H_