Use fucomi instruction to compare floats and put results directly into EFLAGS...

src/ia32/assembler-ia32.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 1796 matching lines @@
 
 
 void Assembler::fucompp() {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   EMIT(0xDA);
   EMIT(0xE9);
 }
 
 
+void Assembler::fucomip() {
+  EnsureSpace ensure_space(this);
+  last_pc_ = pc_;
+  EMIT(0xDF);
+  EMIT(0xE9);
+}
+
+
 void Assembler::fcompp() {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   EMIT(0xDE);
   EMIT(0xD9);
 }
 
 
 void Assembler::fnstsw_ax() {
   EnsureSpace ensure_space(this);
@@ skipping 384 matching lines @@
   push_insn[1] = 13;    // Skip over coverage insns.
   if (coverage_log != NULL) {
     fprintf(coverage_log, "%s\n", file_line);
     fflush(coverage_log);
   }
 }
 
 #endif
 
 } }  // namespace v8::internal