SSE2 truncating double-to-i.

src/ia32/lithium-ia32.cc

 // Copyright 2010 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 1721 matching lines @@
     if (to.IsTagged()) {
       LOperand* value = UseRegister(instr->value());
       LOperand* temp = TempRegister();
 
       // Make sure that temp and result_temp are different registers.
       LUnallocated* result_temp = TempRegister();
       LInstruction* result = new LNumberTagD(value, temp);
       return AssignPointerMap(Define(result, result_temp));
     } else {
       ASSERT(to.IsInteger32());
-      LOperand* value = UseRegister(instr->value());
-      return AssignEnvironment(DefineAsRegister(new LDoubleToI(value)));
+      bool needs_temp = instr->CanTruncateToInt32() &&
+          !CpuFeatures::IsSupported(SSE3);
+      LOperand* value = needs_temp ?
+          UseTempRegister(instr->value()) : UseRegister(instr->value());
+      LOperand* temp = needs_temp ? TempRegister() : NULL;
+      return AssignEnvironment(DefineAsRegister(new LDoubleToI(value, temp)));
     }
   } else if (from.IsInteger32()) {
     if (to.IsTagged()) {
       HValue* val = instr->value();
       LOperand* value = UseRegister(val);
       if (val->HasRange() && val->range()->IsInSmiRange()) {
         return DefineSameAsFirst(new LSmiTag(value));
       } else {
         LInstruction* result = new LNumberTagI(value);
         return AssignEnvironment(AssignPointerMap(DefineSameAsFirst(result)));
@@ skipping 359 matching lines @@
 void LPointerMap::PrintTo(StringStream* stream) const {
   stream->Add("{");
   for (int i = 0; i < pointer_operands_.length(); ++i) {
     if (i != 0) stream->Add(";");
     pointer_operands_[i]->PrintTo(stream);
   }
   stream->Add("} @%d", position());
 }
 
 } }  // namespace v8::internal