For POWER4..POWER8 we align loops of 5..8 instructions to 32 bytes (instead of to 16 bytes) because that executes faster. This is no longer the case on POWER9, so we can just as well only align to 16 bytes.
Bootstrapped and tested on a p9 powerpc64le-linux. Committing to trunk. Segher 2018-03-05 Segher Boessenkool <seg...@kernel.crashing.org> * config/rs6000/rs6000.c (rs6000_loop_align): Don't align tiny loops to 32 bytes when compiling for POWER9. --- gcc/config/rs6000/rs6000.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c index dbc1d79..5cc116f 100644 --- a/gcc/config/rs6000/rs6000.c +++ b/gcc/config/rs6000/rs6000.c @@ -5285,8 +5285,7 @@ rs6000_loop_align (rtx label) || rs6000_tune == PROCESSOR_POWER5 || rs6000_tune == PROCESSOR_POWER6 || rs6000_tune == PROCESSOR_POWER7 - || rs6000_tune == PROCESSOR_POWER8 - || rs6000_tune == PROCESSOR_POWER9)) + || rs6000_tune == PROCESSOR_POWER8)) return 5; else return align_loops_log; -- 1.8.3.1