Make ToBooleanStub more consistent across platforms.

src/x64/full-codegen-x64.cc

 // Copyright 2011 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 546 matching lines @@
   } else {
     if (false_label_ != fall_through_) __ jmp(false_label_);
   }
 }
 
 
 void FullCodeGenerator::DoTest(Expression* condition,
                                Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
-  ToBooleanStub stub;
+  ToBooleanStub stub(result_register());
   __ push(result_register());
   __ CallStub(&stub);
-  __ testq(rax, rax);
+  __ testq(result_register(), result_register());
   // The stub returns nonzero for true.
   Split(not_zero, if_true, if_false, fall_through);
 }
 
 
 void FullCodeGenerator::Split(Condition cc,
                               Label* if_true,
                               Label* if_false,
                               Label* fall_through) {
   if (if_false == fall_through) {
@@ skipping 3653 matching lines @@
   __ ret(0);
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64