bf24f4ec73
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.
|
||
|---|---|---|
| c++tools | ||
| config | ||
| contrib | ||
| fixincludes | ||
| gcc | ||
| gnattools | ||
| gotools | ||
| include | ||
| INSTALL | ||
| intl | ||
| libada | ||
| libatomic | ||
| libbacktrace | ||
| libcc1 | ||
| libcody | ||
| libcpp | ||
| libdecnumber | ||
| libffi | ||
| libgcc | ||
| libgfortran | ||
| libgo | ||
| libgomp | ||
| libhsail-rt | ||
| libiberty | ||
| libitm | ||
| libobjc | ||
| liboffloadmic | ||
| libphobos | ||
| libquadmath | ||
| libsanitizer | ||
| libssp | ||
| libstdc++-v3 | ||
| libvtv | ||
| lto-plugin | ||
| maintainer-scripts | ||
| zlib | ||
| .dir-locals.el | ||
| .gitattributes | ||
| .gitignore | ||
| ABOUT-NLS | ||
| ar-lib | ||
| ChangeLog | ||
| ChangeLog.jit | ||
| ChangeLog.tree-ssa | ||
| compile | ||
| config-ml.in | ||
| config.guess | ||
| config.rpath | ||
| config.sub | ||
| configure | ||
| configure.ac | ||
| COPYING | ||
| COPYING3 | ||
| COPYING3.LIB | ||
| COPYING.LIB | ||
| COPYING.RUNTIME | ||
| depcomp | ||
| install-sh | ||
| libtool-ldflags | ||
| libtool.m4 | ||
| lt~obsolete.m4 | ||
| ltgcc.m4 | ||
| ltmain.sh | ||
| ltoptions.m4 | ||
| ltsugar.m4 | ||
| ltversion.m4 | ||
| MAINTAINERS | ||
| Makefile.def | ||
| Makefile.in | ||
| Makefile.tpl | ||
| missing | ||
| mkdep | ||
| mkinstalldirs | ||
| move-if-change | ||
| multilib.am | ||
| README | ||
| symlink-tree | ||
| test-driver | ||
| ylwrap | ||
This directory contains the GNU Compiler Collection (GCC). The GNU Compiler Collection is free software. See the files whose names start with COPYING for copying permission. The manuals, and some of the runtime libraries, are under different terms; see the individual source files for details. The directory INSTALL contains copies of the installation information as HTML and plain text. The source of this information is gcc/doc/install.texi. The installation information includes details of what is included in the GCC sources and what files GCC installs. See the file gcc/doc/gcc.texi (together with other files that it includes) for usage and porting information. An online readable version of the manual is in the files gcc/doc/gcc.info*. See http://gcc.gnu.org/bugs/ for how to report bugs usefully. Copyright years on GCC source files may be listed using range notation, e.g., 1987-2012, indicating that every year in the range, inclusive, is a copyrightable year that could otherwise be listed individually.