> Meissner, Michael wrote:
> >>> 437.leslie3d -26%
> > it was felt that the PPRE patches that were added on
> November 13th were
> > the cause of the slowdown:
> > http://gcc.gnu.org/ml/gcc/2006-12/msg00023.html
> >
> > Has anybody tried doing a run with just ppre disabled?
>
> Right. PPRE appears to be the reason of slowdown.
>
> -fno-tree-pre gets performance of cpu2006/437.leslie3d back to normal.
> This is the worst case. And that will take much longer to
> verify whole
> set of cpu2006 benchmarks.
If -fno-tree-pre disables PPRE, then it doesn't change much (4.3 relative to 4.2 with -O2):
CPU2006 -O2 -O2 -fno-tree-pre
410.bwaves -6% -8%
416.gamess
433.milc
434.zeusmp
435.gromacs
436.cactusADM
437.leslie3d -26% -27%
444.namd
447.dealII
450.soplex
453.povray
454.calculix
459.GemsFDTD -12% -12%
465.tonto
470.lbm
481.wrf
482.sphinx3
Is PPRE enabled at -O2 at all? I couldn't confirm that from the original patches, which enabled PPRE only at -O3.