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Adhemerval Zanella 1cae0550e8 math: Use tgamma from CORE-MATH
The current implementation precision shows the following accuracy, on
one range ([-20,20]) with 10e9 uniform randomly generated numbers for
each range (first column is the accuracy in ULP, with '0' being
correctly rounded, second is the number of samples with the
corresponding precision):

* Range [-20,20]
 * FE_TONEAREST
     0:       4504877808  45.05%
     1:       4402224940  44.02%
     2:        947652295   9.48%
     3:        131076831   1.31%
     4:         13222216   0.13%
     5:           910045   0.01%
     6:            35253   0.00%
     7:              606   0.00%
     8:                6   0.00%
 * FE_UPWARD
     0:       3477307921  34.77%
     1:       4838637866  48.39%
     2:       1413942684  14.14%
     3:        240762564   2.41%
     4:         27113094   0.27%
     5:          2130934   0.02%
     6:           102599   0.00%
     7:             2324   0.00%
     8:               14   0.00%
 * FE_DOWNWARD
     0:       3923545410  39.24%
     1:       4745067290  47.45%
     2:       1137899814  11.38%
     3:        171596912   1.72%
     4:         20013805   0.20%
     5:          1773899   0.02%
     6:            99911   0.00%
     7:             2928   0.00%
     8:               31   0.00%
 * FE_TOWARDZERO
     0:       3697160741  36.97%
     1:       4731951491  47.32%
     2:       1303092738  13.03%
     3:        231969191   2.32%
     4:         32344517   0.32%
     5:          3283092   0.03%
     6:           193010   0.00%
     7:             5175   0.00%
     8:               45   0.00%

The CORE-MATH implementation is correctly rounded for any rounding mode.
The code was adapted to glibc style and to use the definition of
math_config.h (to handle errno, overflow, and underflow).

Benchtest on x64_64 (Ryzen 9 5900X, gcc 14.2.1), aarch64 (Neoverse-N1,
gcc 13.3.1), and powerpc (POWER10, gcc 13.2.1) shows:

reciprocal-throughput        master        patched   improvement
x86_64                     237.7960       175.4090        26.24%
x86_64v2                   232.9320       163.4460        29.83%
x86_64v3                   193.0680        89.7721        53.50%
aarch64                    113.6340        56.7350        50.07%
power10                     92.0617        26.6137        71.09%

Latency                      master        patched   improvement
x86_64                     266.7190       208.0130        22.01%
x86_64v2                   263.6070       200.0280        24.12%
x86_64v3                   214.0260       146.5180        31.54%
aarch64                    114.4760        58.5235        48.88%
power10                     84.3718        35.7473        57.63%

Checked on x86_64-linux-gnu, aarch64-linux-gnu, and
powerpc64le-linux-gnu.

Reviewed-by: DJ Delorie <dj@redhat.com>
2025-10-27 09:34:04 -03:00
ChangeLog.old Create ChangeLog.old/ChangeLog.31 2025-07-28 20:22:55 +02:00
advisories advisories: s/CVE-id/CVE-Id/ (the lowercase i breaks our tooling) 2025-07-26 15:21:27 +02:00
argp argp: Fix shift bug 2025-06-02 13:32:19 -03:00
assert assert: Refactor assert/assert_perror 2025-09-23 10:29:24 -03:00
benchtests plot_strings.py: Replace np.complex with complex 2025-10-22 07:52:54 +08:00
bits Add once_flag, ONCE_FLAG_INIT and call_once to stdlib.h for C23 2025-10-01 15:15:15 +00:00
catgets catgets: Remove catgets/config.h 2025-10-21 09:24:19 -03:00
conform linknamespace: Use 'ALLOWLIST' instead of 'WHITELIST' in code. 2025-05-21 12:47:49 -04:00
csu
ctype Use TLS initial-exec model for __libc_tsd_CTYPE_* thread variables [BZ #33234] 2025-08-05 13:06:12 +02:00
debug Implement C23 memset_explicit (bug 32378) 2025-10-01 15:14:09 +00:00
dirent
dlfcn elf: Add SFrame support to _dl_find_object function 2025-07-14 10:56:35 +01:00
elf sprof: fix -Wformat warnings on 32-bit hosts 2025-10-22 09:48:44 -07:00
gmon gmon: Only used -fno-tree-loop-distribute-patterns if compiler supports it 2025-10-21 09:27:01 -03:00
gnulib
hesiod
htl htl: move sem_unlink into libc. 2025-08-18 01:06:41 +02:00
hurd Suppress -Wmaybe-uninitialized only for gcc 2025-10-21 09:24:05 -03:00
iconv Suppress -Wmaybe-uninitialized only for gcc 2025-10-21 09:24:05 -03:00
iconvdata iconvdata: Fix clang -Wstring-plus-int clang warning 2025-10-21 09:24:14 -03:00
include stdio: Only use __va_arg_pack if compiler supports it 2025-10-21 09:26:04 -03:00
inet inet-fortified: fix namespace violation (bug 33227) 2025-07-29 11:50:29 +01:00
intl
io Tests: Create files with mode 0666, not 0777 (bug 33171) 2025-09-01 15:12:28 +02:00
libio libio: Add terminating NUL when the first character is EOF in getdelim [BZ #28038] 2025-10-09 17:38:01 -07:00
locale Suppress -Wmaybe-uninitialized only for gcc 2025-10-21 09:24:05 -03:00
localedata tests-mbwc/tst_funcs.h: Fix typo 2025-10-01 14:49:10 -03:00
login login: fix ut_line comparison logic 2025-08-29 14:49:19 -04:00
mach hurd: Make __getrandom_early_init call __mach_init 2025-06-09 08:34:06 +00:00
malloc malloc: fix large tcache code to check for exact size match 2025-10-24 16:55:02 +00:00
manual Implement C23 memalignment 2025-10-17 16:56:59 +00:00
math math: Use tgamma from CORE-MATH 2025-10-27 09:34:04 -03:00
mathvec
misc misc: Fix clang -Wstring-plus-int warnings on syslog 2025-10-22 16:35:39 -03:00
nis Suppress -Wmaybe-uninitialized only for gcc 2025-10-21 09:24:05 -03:00
nptl nptl: Fix Wincompatible-pointer-types on clang 2025-10-21 09:24:06 -03:00
nptl_db Suppress -Wmaybe-uninitialized only for gcc 2025-10-21 09:24:05 -03:00
nscd atomic: Remove atomic_forced_read 2025-10-08 12:59:30 +00:00
nss Alphabetize nss/Makefile 2025-10-09 09:50:27 +02:00
po po: Update swedish translations 2025-07-25 19:31:37 +02:00
posix posix: Fix memory leak a memory leak in glob. 2025-10-21 19:09:45 -07:00
resolv Suppress -Wmaybe-uninitialized only for gcc 2025-10-21 09:24:05 -03:00
resource resource/Makefile: Split and sort tests 2025-06-19 13:33:34 +02:00
rt
scripts Use Linux 6.17 in build-many-glibcs.py 2025-10-01 15:15:43 +00:00
setjmp
signal
socket
soft-fp
stdio-common stdio: Fix -Wtautological-constant-out-of-range-compare on clang 2025-10-21 09:26:04 -03:00
stdlib Adjust stdint for clang-20 2025-10-20 11:33:54 -03:00
string Suppress -Wmaybe-uninitialized only for gcc 2025-10-21 09:24:05 -03:00
sunrpc sunrpc: Fix clang build 2025-10-21 09:27:05 -03:00
support support: Handle clang support/dtotimespec.c on dtotimespec 2025-10-21 09:26:04 -03:00
sysdeps math: Use tgamma from CORE-MATH 2025-10-27 09:34:04 -03:00
sysvipc
termios termios: SPEED_MAX and BAUD_MAX constants 2025-07-20 17:17:41 +02:00
time
timezone configure: Use -Wno-maybe-uninitialized iff compiler supports it 2025-10-21 09:24:03 -03:00
wcsmbs
wctype
.b4-config
.clang-format
.gitattributes
.gitignore
CONTRIBUTED-BY
COPYING
COPYING.LIB
INSTALL INSTALL: Update newest tested binutils version 2025-07-28 16:49:01 +02:00
LICENSES
MAINTAINERS
Makeconfig Build glibc with -ftrapping-math 2025-10-20 11:33:54 -03:00
Makefile Makefile: Add ld.so.conf with libgcc dir to testroot.pristine 2025-07-09 15:46:14 +02:00
Makefile.help
Makefile.in Remove test-have-mamx-tile from Makefile.in 2025-08-23 15:58:00 -07:00
Makerules Makerules: Use 'original' instead of 'master' in source. 2025-05-21 12:48:04 -04:00
NEWS Implement C23 memalignment 2025-10-17 16:56:59 +00:00
README
Rules malloc: Fix tests-malloc-largetcache tests 2025-06-17 14:22:49 -03:00
SECURITY.md
SHARED-FILES math: Use tgamma from CORE-MATH 2025-10-27 09:34:04 -03:00
abi-tags
aclocal.m4 x86: Set have-protected-data to no if unsupported 2025-08-22 17:55:32 -07:00
config.h.in hurd: implement RLIMIT_AS against Mach RPCs 2025-09-22 00:52:37 +02:00
config.make.in Disable SFrame support by default 2025-07-24 15:51:58 -03:00
configure Fix configure from ab22e5ec37 2025-10-22 17:23:12 -03:00
configure.ac gmon: Only used -fno-tree-loop-distribute-patterns if compiler supports it 2025-10-21 09:27:01 -03:00
extra-lib.mk
gen-locales.mk
libc-abis
libof-iterator.mk
o-iterator.mk
shlib-versions
test-skeleton.c
version.h Bump version to 2.42.9000 2025-07-28 20:31:31 +02:00

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