http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54716
--- Comment #9 from Uros Bizjak <ubizjak at gmail dot com> 2012-09-26 20:59:24 UTC --- (In reply to comment #8) > (In reply to comment #7) > > I haven't noticed a measurable performance difference though on Intel SNB > > 2600 > > CPU though, so perhaps the patch isn't needed. > > Ah, I assumed they had a good reason for creating so many variants of the same > instruction. If there is no difference (or even a difference in the wrong > direction because of the instruction size), feel free to close the bug. I think we should still go with the proposed patch. Insn size is handled by choosing *PS mode attribute for -Os in the insn pattern, and there is no size difference for AVX. If some target prefers *PS variants, there is always X86_TUNE_SSE_PACKED_SINGLE_INSN_OPTIMAL flag available. But please put the code into a helper function. Due to VI mode iterator, the code is emitted eight times!
