On Fri, 9 Aug 2024 at 10:29, Alex Coplan <alex.cop...@arm.com> wrote: > > Together with the preparatory compiler patches, this patch restores > unrolling in std::__find_if, but this time relying on the compiler to do > it by using: > > #pragma GCC unroll 4 > > which should restore the majority of the regression relative to the > hand-unrolled version while still being vectorizable with WIP alignment > peeling enhancements. > > On Neoverse V1 with LTO, this reduces the regression in xalancbmk (from > SPEC CPU 2017) from 5.8% to 1.7% (restoring ~71% of the lost > performance). > > Bootstrapped/regtested on aarch64-linux-gnu, OK for trunk?
Yes, OK - thanks. > > Thanks, > Alex > > libstdc++-v3/ChangeLog: > > PR libstdc++/116140 > * include/bits/stl_algobase.h (std::__find_if): Add #pragma to > request GCC to unroll the loop. > --- > libstdc++-v3/include/bits/stl_algobase.h | 1 + > 1 file changed, 1 insertion(+) >
