[Bug target/52908] xop-mul-1:f9 miscompiled on bulldozer (-mxop)

ubizjak at gmail dot com gcc-bugzilla@gcc.gnu.org
Fri May 4 12:52:00 GMT 2012


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52908

--- Comment #5 from Uros Bizjak <ubizjak at gmail dot com> 2012-05-04 12:51:49 UTC ---
(In reply to comment #4)

> A Quick make check on i386.exp result is shown below: 
> 
> Tests that now fail, but worked before:
> 
> gcc.target/i386/xop-imul32widen-vector.c scan-assembler vpmacsdql

This is expected, there is no need to emit vpmacsdql, IMO vpmuldq works as good
(if not even better, since we don't have to preload accumulator with zero). The
test should be either changed to really emit vpmacsdql, or asm scan should be
adjusted.

> Tests that now work, but didn't before:
> 
> gcc.target/i386/xop-mul-1.c execution test

Yes this one should be fixed with the patch.

If the change vmpacsdql -> vpmuldq is OK with you, I can commit the patch, but
I'd ask you for full bootstrap/regression test.



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