Port code to load an integer directly from a heap number from ia32 to x64....

src/ia32/codegen-ia32.cc

 // Copyright 2006-2009 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 7687 matching lines @@
 
 
 // Get the integer part of a heap number.  Surprisingly, all this bit twiddling
 // is faster than using the built-in instructions on floating point registers.
 // Trashes edi and ebx.  Dest is ecx.  Source cannot be ecx or one of the
 // trashed registers.
 void IntegerConvert(MacroAssembler* masm,
                     Register source,
                     bool use_sse3,
                     Label* conversion_failure) {
+  ASSERT(!source.is(ecx) && !source.is(edi) && !source.is(ebx));
   Label done, right_exponent, normal_exponent;
   Register scratch = ebx;
   Register scratch2 = edi;
   // Get exponent word.
   __ mov(scratch, FieldOperand(source, HeapNumber::kExponentOffset));
   // Get exponent alone in scratch2.
   __ mov(scratch2, scratch);
   __ and_(scratch2, HeapNumber::kExponentMask);
   if (use_sse3) {
     CpuFeatures::Scope scope(SSE3);
@@ skipping 2309 matching lines @@
 
   // Call the runtime; it returns -1 (less), 0 (equal), or 1 (greater)
   // tagged as a small integer.
   __ bind(&runtime);
   __ TailCallRuntime(ExternalReference(Runtime::kStringCompare), 2, 1);
 }
 
 #undef __
 
 } }  // namespace v8::internal