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Noah Goldstein 0d5b36c8cc x86: Optimize strcmp-avx2.S
Optimization are primarily to the loop logic and how the page cross
logic interacts with the loop.

The page cross logic is at times more expensive for short strings near
the end of a page but not crossing the page. This is done to retest
the page cross conditions with a non-faulty check and to improve the
logic for entering the loop afterwards. This is only particular cases,
however, and is general made up for by more than 10x improvements on
the transition from the page cross -> loop case.

The non-page cross cases are improved most for smaller sizes [0, 128]
and go about even for (128, 4096]. The loop page cross logic is
improved so some more significant speedup is seen there as well.

test-strcmp, test-strncmp, test-wcscmp, and test-wcsncmp all pass.

Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>
(cherry picked from commit b77b06e0e2)
2022-05-05 08:53:34 -07:00
argp argp: Avoid undefined behaviour when invoking qsort(). 2021-02-04 16:44:29 -03:00
assert Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
benchtests tests: use xmalloc to allocate implementation array 2021-07-28 17:45:19 +05:30
bits elf: Issue la_symbind for bind-now (BZ #23734) 2022-04-12 13:32:59 -04:00
catgets Move malloc hooks into a compat DSO 2021-07-22 18:37:59 +05:30
ChangeLog.old Update ChangeLog.old/ChangeLog.23. 2021-08-01 21:33:43 -04:00
conform Use $(pie-default) with conformtest 2021-12-13 20:59:48 +05:30
crypt Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
csu elf: Add _dl_audit_preinit 2022-04-08 14:18:12 -04:00
ctype Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
debug misc: Fix rare fortify crash on wchar funcs. [BZ 29030] 2022-04-25 18:44:27 +05:30
dirent Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
dlfcn dlfcn: Do not use rtld_active () to determine ld.so state (bug 29078) 2022-04-26 15:28:39 +02:00
elf dlfcn: Do not use rtld_active () to determine ld.so state (bug 29078) 2022-04-26 15:28:39 +02:00
gmon Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
gnulib Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
grp Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
gshadow Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
hesiod Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
htl htl: Let libc call __pthread_mutex_{,try,un}lock 2021-07-13 23:36:58 +02:00
hurd hurd: Export _hurd_libc_proc_init 2021-04-12 00:23:36 +02:00
iconv iconvconfig: Fix behaviour with --prefix [BZ #28199] 2021-09-13 20:51:04 +05:30
iconvdata gconv: Do not emit spurious NUL character in ISO-2022-JP-3 (bug 28524) 2021-11-04 21:28:43 +01:00
include elf: Issue audit la_objopen for vDSO 2022-04-08 14:18:12 -04:00
inet resolv: Deprecate legacy interfaces in libresolv 2021-07-19 07:55:42 +02:00
intl intl/plural.y: Avoid conflicting declarations of yyerror and yylex 2021-12-23 13:48:04 +01:00
io linux: Fix fchmodat with AT_SYMLINK_NOFOLLOW for 64 bit time_t (BZ#29097) 2022-04-28 10:10:30 -03:00
libio Make sure that the fortified function conditionals are constant 2022-03-11 20:36:24 +05:30
locale localedef: Handle symbolic links when generating locale-archive 2022-03-03 11:58:03 +01:00
localedata Move malloc hooks into a compat DSO 2021-07-22 18:37:59 +05:30
login login: Move libutil into libc 2021-06-30 08:43:37 +02:00
mach Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
malloc Handle NULL input to malloc_usable_size [BZ #28506] 2021-10-29 14:56:53 +05:30
manual manual: Clarify that abbreviations of long options are allowed 2022-05-04 15:59:39 +05:30
math Update floating-point feature test macro handling for C2X 2021-06-01 14:22:06 +00:00
mathvec Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
misc misc: Fix rare fortify crash on wchar funcs. [BZ 29030] 2022-04-25 18:44:27 +05:30
nis nis: nis_local_group may read from __nisgroup[-1] (bug 28075) 2021-07-12 07:58:07 +02:00
nptl nptl: Fix pthread_cancel cancelhandling atomic operations 2022-04-20 12:22:34 -03:00
nptl_db nptl_db: Re-use the ELF-to-abilist converter for ABI checking 2021-06-29 22:17:08 +02:00
nscd Use 64 bit time_t stat internally 2021-06-22 12:09:52 -03:00
nss hurd: Fix arbitrary error code 2022-04-18 17:54:13 +02:00
po po/nl.po: Update Dutch translation. 2021-08-01 20:52:28 -04:00
posix posix/glob.c: update from gnulib 2022-04-28 11:57:23 -04:00
pwd Annotate additional APIs with GCC attribute access. 2021-05-06 11:01:05 -06:00
resolv Move malloc hooks into a compat DSO 2021-07-22 18:37:59 +05:30
resource y2038: Add support for 64-bit time on legacy ABIs 2021-06-15 10:42:11 -03:00
rt librt: add test (bug 28213) 2021-08-16 11:35:35 +05:30
scripts scripts/glibcelf.py: Mark as UNSUPPORTED on Python 3.5 and earlier 2022-04-26 15:59:12 +02:00
setjmp nptl: Move __pthread_unwind_next into libc 2021-04-21 19:49:50 +02:00
shadow Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
signal y2038: Add support for 64-bit time on legacy ABIs 2021-06-15 10:42:11 -03:00
socket Make sure that the fortified function conditionals are constant 2022-03-11 20:36:24 +05:30
soft-fp soft-fp: Add __extendhfsf2/__extendhfdf2, __truncsfhf2/__truncdfhf2, __eqhf2/__nehf2 2021-07-07 08:01:32 -07:00
stdio-common Move malloc hooks into a compat DSO 2021-07-22 18:37:59 +05:30
stdlib fortify: Fix spurious warning with realpath 2022-03-11 20:36:24 +05:30
string x86-64: Use notl in EVEX strcmp [BZ #28646] 2022-04-26 18:18:16 -07:00
sunrpc CVE-2022-23218: Buffer overflow in sunrpc svcunix_create (bug 28768) 2022-01-17 11:49:25 +01:00
support debug: Synchronize feature guards in fortified functions [BZ #28746] 2022-03-11 20:36:24 +05:30
sysdeps x86: Optimize strcmp-avx2.S 2022-05-05 08:53:34 -07:00
sysvipc Linux: Cleanups after librt move 2021-06-28 09:51:01 +02:00
termios Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
time timezone: handle truncated timezones from tzcode-2021d and later (BZ #28707) 2022-01-07 10:20:58 +01:00
timezone timezone: test-case for BZ #28707 2022-01-07 10:21:11 +01:00
wcsmbs debug: Synchronize feature guards in fortified functions [BZ #28746] 2022-03-11 20:36:24 +05:30
wctype Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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abi-tags Remove the bulk of the NaCl port. 2017-05-20 08:09:10 -04:00
aclocal.m4 configure: Replaced obsolete AC_TRY_COMPILE 2021-06-04 10:16:00 -03:00
config.h.in i386: Remove broken CAN_USE_REGISTER_ASM_EBP (bug 28771) 2022-01-13 15:21:32 +01:00
config.make.in Add pthread-in-libc, libpthread-routines-var, librt-routines-var 2021-05-03 08:13:32 +02:00
configure Default to --with-default-link=no (bug 25812) 2022-04-22 11:31:14 +02:00
configure.ac Default to --with-default-link=no (bug 25812) 2022-04-22 11:31:14 +02:00
COPYING
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extra-lib.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
gen-locales.mk Improve gen-locales.mk and gen-locale.sh to make test files with @ options work 2018-02-27 17:01:57 +01:00
INSTALL INSTALL: Rephrase -with-default-link documentation 2022-04-26 15:27:43 +02:00
libc-abis riscv: support GNU indirect function 2021-01-10 21:25:13 -05:00
libof-iterator.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
LICENSES Prefer https to http for gnu.org and fsf.org URLs 2019-09-07 02:43:31 -07:00
MAINTAINERS Add MAINTAINERS 2017-05-11 13:38:30 -04:00
Makeconfig Run conform/ tests using newly built libc 2021-12-13 09:07:38 +05:30
Makefile Install shared objects under their ABI names 2021-06-28 08:33:57 +02:00
Makefile.help Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
Makefile.in
Makerules debug: Autogenerate _FORTIFY_SOURCE tests 2022-03-11 20:36:24 +05:30
NEWS linux: Fix fchmodat with AT_SYMLINK_NOFOLLOW for 64 bit time_t (BZ#29097) 2022-04-28 10:10:30 -03:00
o-iterator.mk
README Documentation for the RISC-V 32-bit port 2020-08-27 08:17:44 -07:00
Rules Move malloc hooks into a compat DSO 2021-07-22 18:37:59 +05:30
shlib-versions nss: Do not mention NSS test modules in <gnu/lib-names.h> 2022-03-11 11:13:34 +01:00
test-skeleton.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
version.h Prepare for glibc 2.34 release. 2021-08-01 21:24:04 -04:00

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