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| author | H.J. Lu <hjl.tools@gmail.com> | 2021-01-21 18:51:35 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2021-03-31 05:28:32 -0700 |
| commit | bf24f4ec73b65454ea0edcd6ab5616f04958d41e (patch) | |
| tree | fec9c1991dec8ed9d18e1287bc87a31e9c6ccba0 /gcc/tree-data-ref.c | |
| parent | 1393938e4c7dab9306cdce5a73d93b242fc246ec (diff) | |
| download | gcc-bf24f4ec73b65454ea0edcd6ab5616f04958d41e.zip gcc-bf24f4ec73b65454ea0edcd6ab5616f04958d41e.tar.gz gcc-bf24f4ec73b65454ea0edcd6ab5616f04958d41e.tar.bz2 | |
x86: Update memcpy/memset inline strategies for Ice Lake
Simply memcpy and memset inline strategies to avoid branches for
-mtune=icelake:
1. With MOVE_RATIO and CLEAR_RATIO == 17, GCC will use integer/vector
load and store for up to 16 * 16 (256) bytes when the data size is
fixed and known.
2. Inline only if data size is known to be <= 256.
a. Use "rep movsb/stosb" with simple code sequence if the data size
is a constant.
b. Use loop if data size is not a constant.
3. Use memcpy/memset libray function if data size is unknown or > 256.
On Ice Lake processor with -march=native -Ofast -flto,
1. Performance impacts of SPEC CPU 2017 rate are:
500.perlbench_r -0.93%
502.gcc_r 0.36%
505.mcf_r 0.31%
520.omnetpp_r -0.07%
523.xalancbmk_r -0.53%
525.x264_r -0.09%
531.deepsjeng_r -0.19%
541.leela_r 0.16%
548.exchange2_r 0.22%
557.xz_r -1.64%
Geomean -0.24%
503.bwaves_r -0.01%
507.cactuBSSN_r 0.00%
508.namd_r 0.12%
510.parest_r 0.07%
511.povray_r 0.29%
519.lbm_r 0.00%
521.wrf_r -0.38%
526.blender_r 0.16%
527.cam4_r 0.18%
538.imagick_r 0.76%
544.nab_r -0.84%
549.fotonik3d_r -0.07%
554.roms_r -0.01%
Geomean 0.02%
2. Significant impacts on eembc benchmarks are:
eembc/nnet_test 9.90%
eembc/mp2decoddata2 16.42%
eembc/textv2data3 -4.86%
eembc/qos 12.90%
gcc/
* config/i386/i386-expand.c (expand_set_or_cpymem_via_rep):
For TARGET_PREFER_KNOWN_REP_MOVSB_STOSB, don't convert QImode
to SImode.
(decide_alg): For TARGET_PREFER_KNOWN_REP_MOVSB_STOSB, use
"rep movsb/stosb" only for known sizes.
* config/i386/i386-options.c (processor_cost_table): Use Ice
Lake cost for Cannon Lake, Ice Lake, Tiger Lake, Sapphire
Rapids and Alder Lake.
* config/i386/i386.h (TARGET_PREFER_KNOWN_REP_MOVSB_STOSB): New.
* config/i386/x86-tune-costs.h (icelake_memcpy): New.
(icelake_memset): Likewise.
(icelake_cost): Likewise.
* config/i386/x86-tune.def (X86_TUNE_PREFER_KNOWN_REP_MOVSB_STOSB):
New.
gcc/testsuite/
* gcc.target/i386/memcpy-strategy-5.c: New test.
* gcc.target/i386/memcpy-strategy-6.c: Likewise.
* gcc.target/i386/memcpy-strategy-7.c: Likewise.
* gcc.target/i386/memcpy-strategy-8.c: Likewise.
* gcc.target/i386/memset-strategy-3.c: Likewise.
* gcc.target/i386/memset-strategy-4.c: Likewise.
* gcc.target/i386/memset-strategy-5.c: Likewise.
* gcc.target/i386/memset-strategy-6.c: Likewise.
Diffstat (limited to 'gcc/tree-data-ref.c')
0 files changed, 0 insertions, 0 deletions