On Fri, Sep 27, 2013 at 8:46 AM, H.J. Lu <hjl.to...@gmail.com> wrote:
>> So I would incline to be apply extra care on this flag and keep it for extra >> release or two. Most of gcc.opensuse.org testing runs on these and adding >> random branch mispredictions will trash them. >> >> At the related note, would would you think of >> X86_TUNE_PARTIAL_FLAG_REG_STALL? >> I benchmarked it on my I5 notebook and it seems to have no measurable effects >> on spec2k6. >> >> I also did some benchmarking of the patch to disable alignments you proposed. >> Unforutnately I can measure slowdowns on fam10/bdver/and on botan/hand >> written >> loops even for core. > > I am not surprised about hand written loops. Have you > tried SPEC CPU rate? > >> I am considering to drop the branch target/function alignment and keep only >> loop >> alignment, but I did not test this yet. >> This sounds a good idea. I will give it a try on Intel processors. -- H.J.
