X64: Fix ToBoolean(floating point).

src/x64/assembler-x64.cc

 // 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 1431 matching lines @@
   store_rax(ref.address(), RelocInfo::EXTERNAL_REFERENCE);
 }
 
 
 void Assembler::testb(Register reg, Immediate mask) {
   ASSERT(is_int8(mask.value_));
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   if (reg.is(rax)) {
     emit(0xA8);
-    emit(mask);
+    emit(mask.value_);  // Low byte emitted.
   } else {
     if (reg.code() > 3) {
       // Register is not one of al, bl, cl, dl.  Its encoding needs REX.
       emit_rex_32(reg);
     }
     emit(0xF6);
     emit_modrm(0x0, reg);
     emit(mask.value_);  // Low byte emitted.
   }
 }
@@ skipping 672 matching lines @@
 bool BreakLocationIterator::IsDebugBreakAtReturn()  {
   UNIMPLEMENTED();
   return false;
 }
 
 void BreakLocationIterator::SetDebugBreakAtReturn()  {
   UNIMPLEMENTED();
 }
 
 } }  // namespace v8::internal