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| author | Wilco Dijkstra <wilco.dijkstra@arm.com> | 2025-03-03 16:47:32 +0000 |
|---|---|---|
| committer | Wilco Dijkstra <wilco.dijkstra@arm.com> | 2025-03-06 17:37:07 +0000 |
| commit | f870302515d5fcf7355f0108c3ead0038ff326fd (patch) | |
| tree | dfd4cf54c1e1d6400a46e3dba4b32ebff0e9c2d1 /gcc | |
| parent | 179e01085b0aed111ef1f7908c4b87c800f880e9 (diff) | |
| download | gcc-f870302515d5fcf7355f0108c3ead0038ff326fd.zip gcc-f870302515d5fcf7355f0108c3ead0038ff326fd.tar.gz gcc-f870302515d5fcf7355f0108c3ead0038ff326fd.tar.bz2 | |
AArch64: Enable early scheduling for -O3 and higher (PR118351)
Enable the early scheduler on AArch64 for O3/Ofast. This means GCC15 benefits
from much faster build times with -O2, but avoids the regressions in lbm which
is very sensitive to minor scheduling changes due to long FMA chains.
gcc:
PR target/118351
PR other/38768
* common/config/aarch64/aarch64-common.cc: Enable early scheduling with
-O3 and higher.
* doc/invoke.texi (-fschedule-insns): Update comment.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/common/config/aarch64/aarch64-common.cc | 4 | ||||
| -rw-r--r-- | gcc/doc/invoke.texi | 4 |
2 files changed, 6 insertions, 2 deletions
diff --git a/gcc/common/config/aarch64/aarch64-common.cc b/gcc/common/config/aarch64/aarch64-common.cc index 500bf78..b9ed836 100644 --- a/gcc/common/config/aarch64/aarch64-common.cc +++ b/gcc/common/config/aarch64/aarch64-common.cc @@ -53,8 +53,10 @@ static const struct default_options aarch_option_optimization_table[] = { OPT_LEVELS_ALL, OPT_fomit_frame_pointer, NULL, 0 }, /* Enable -fsched-pressure by default when optimizing. */ { OPT_LEVELS_1_PLUS, OPT_fsched_pressure, NULL, 1 }, - /* Disable early scheduling due to high compile-time overheads. */ + /* Except for -O3 and higher, disable early scheduling due to high + compile-time overheads. */ { OPT_LEVELS_ALL, OPT_fschedule_insns, NULL, 0 }, + { OPT_LEVELS_3_PLUS, OPT_fschedule_insns, NULL, 1 }, /* Enable redundant extension instructions removal at -O2 and higher. */ { OPT_LEVELS_2_PLUS, OPT_free, NULL, 1 }, { OPT_LEVELS_2_PLUS, OPT_mearly_ra_, NULL, AARCH64_EARLY_RA_ALL }, diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 6f0779b..304de88 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -13507,7 +13507,9 @@ helps machines that have slow floating point or memory load instructions by allowing other instructions to be issued until the result of the load or floating-point instruction is required. -Enabled at levels @option{-O2}, @option{-O3}. +Conventionally enabled at optimization levels @option{-O2} and @option{-O3}. +However, many targets override this behavior. For example, on x86, it is +disabled at all levels, while on AArch64, it is enabled only at @option{-O3}. @opindex fschedule-insns2 @item -fschedule-insns2 |