On Thu, May 16, 2013 at 10:40 PM, Bill Schmidt <wschm...@linux.vnet.ibm.com> wrote: > This removes two degradations in CPU2006 for 32-bit PowerPC due to lost > vectorization opportunities. Previously, GCC treated malloc'd arrays as > only guaranteeing 4-byte alignment, even though the glibc implementation > guarantees 8-byte alignment. This raises the guarantee to 8 bytes, > which is sufficient to permit the missed vectorization opportunities. > > The guarantee for 64-bit PowerPC should be raised to 16-byte alignment, > but doing so currently exposes a latent bug that degrades a 64-bit > benchmark. I have therefore not included that change at this time, but > added a FIXME recording the information. > > Bootstrapped and tested on powerpc64-unknown-linux-gnu with no new > regressions. Verified that SPEC CPU2006 degradations are fixed with no > new degradations. Ok for trunk? Also, do you want any backports?
Okay. If you think that this is appropriate for 4.8 branch, that is okay as well. Is there a FSF GCC Bugzilla open for the 437.leslie3d problem? The FIXME doesn't need to contain the complete explanation, but it would be nice to reference a longer explanation and not pretend to be Fermat's theorem that is too large to write in the marge. Thanks, David
