On Wed, Dec 16, 2015 at 6:20 PM, Michael Meissner <meiss...@linux.vnet.ibm.com> wrote: > My first mail did not seem to be delivered, so I'm trying again. > > This fixes a bug with the debug switch -mvsx-timode that we would eventually > like to enable by default on PowerPC little endian server systems. The bug is > that the load with rotate or rotate with store instructions needed on power8 > little endian systems used VEC_SELECT to swap the 64-bit words. This patch > uses ROTATE for TImode, just like I did for KFmode. > > Without this patch, 10 of the 30 spec 2006 benchmarks fail to compile on a > little endian PowerPC system with -mvsx-timode. With the patch, all 30 > benchmarks compile and do the spec verification. > > In developing the patch, I noticed that the generic swap optimizations that > are > done for vector types are not done for TImode, since we don't split the > TImoves > until after register allocation when we discover a vector register was used > instead of a GPR register. So, I added a peephole2 to catch the common case > of > store followed by load, eliminating the pair of ROTATE insns. > > I bootstrapped it on both a big endian power7 and a little endian power8 > system > with no regressions. Is it ok to install on the trunk? > > At the current time, I don't see the need to back port it to GCC 5 (though the > backport is fairly simple), because it isn't on by default in GCC 5, and we > don't plan to eventually have -mvsx-timode and -mlra on by default in that > branch. > > [gcc] > 2015-12-15 Michael Meissner <meiss...@linux.vnet.ibm.com> > > PR target/68805 > * config/rs6000/rs6000.c (rs6000_gen_le_vsx_permute): Use ROTATE > instead of VEC_SELECT for TImode. > > * config/rs6000/vsx.md (VSX_LE): Move TImode from VSX_LE to > VSX_LE_128, so that we use ROTATE to swap the 64-bit words instead > of using VEC_SELECT. > (VSX_LE_128): Likewise. > (define_peephole2): Add peephole to eliminate double xxpermdi when > copying TImode. > > [gcc/testsuite] > 2015-12-15 Michael Meissner <meiss...@linux.vnet.ibm.com> > > PR target/68805 > * gcc.target/powerpc/pr68805.c: New test.
Okay. Thanks, David
