Fix bug that errnoeously sets FPU exception.

src/x64/macro-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 1262 matching lines @@
   movq(Operand(kScratchRegister, 0), rsp);
 }
 
 
 void MacroAssembler::Ret() {
   ret(0);
 }
 
 
 void MacroAssembler::FCmp() {
-  fcompp();
+  fucompp();
   push(rax);
   fnstsw_ax();
   if (CpuFeatures::IsSupported(CpuFeatures::SAHF)) {
     sahf();
   } else {
     shrl(rax, Immediate(8));
     and_(rax, Immediate(0xFF));
     push(rax);
     popfq();
   }
@@ skipping 806 matching lines @@
   // Indicate that code has changed.
   CPU::FlushICache(address_, size_);
 
   // Check that the code was patched as expected.
   ASSERT(masm_.pc_ == address_ + size_);
   ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
 }
 
 
 } }  // namespace v8::internal