Make X64 double-to-int32 conversion use the 64-bit version of cvttsd2si.

src/ia32/codegen-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 10187 matching lines @@
 // trashed registers.
 void IntegerConvert(MacroAssembler* masm,
                     Register source,
                     TypeInfo type_info,
                     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;
+  if (type_info.IsInteger32() && CpuFeatures::IsEnabled(SSE2)) {
+    if (FLAG_debug_code) {
+      // Do some testing to see that the type info is correct.

[William Hesse, 2010/05/10 11:08:43]

This comment should be a TODO, or it should actually be implemented, or the if
statement should be removed.

[Lasse Reichstein, 2010/05/10 11:20:44]

Removed (I meant to but forgot, well spotted).

+    }
+    CpuFeatures::Scope scope(SSE2);
+    __ cvttsd2si(ecx, FieldOperand(source, HeapNumber::kValueOffset));
+    return;
+  }
   if (!type_info.IsInteger32() || !use_sse3) {
     // 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);
     if (!type_info.IsInteger32()) {
@@ skipping 2980 matching lines @@
 
   // Call the runtime; it returns -1 (less), 0 (equal), or 1 (greater)
   // tagged as a small integer.
   __ bind(&runtime);
   __ TailCallRuntime(Runtime::kStringCompare, 2, 1);
 }
 
 #undef __
 
 } }  // namespace v8::internal