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Adhemerval Zanella 9247f53219 math: Use log10f from CORE-MATH
The CORE-MATH implementation is correctly rounded (for any rounding mode)
and shows better performance compared to the generic log10f.

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):

Latency                      master        patched   improvement
x86_64                      49.9017        33.5143        32.84%
x86_64v2                    50.4878        33.5623        33.52%
x86_64v3                    50.0991        27.6078        44.89%
i686                        140.874        106.086        24.69%
aarch64                     19.2846        11.3573        41.11%
power10                     14.0994        7.7739        44.86%
powerpc                     14.2898        7.92497        44.54%

reciprocal-throughput        master        patched   improvement
x86_64                      17.8336        12.9074        27.62%
x86_64v2                    16.4418        11.3220        31.14%
x86_64v3                    15.6002        10.5158        32.59%
i686                        66.0678        80.2287        -21.43%
aarch64                      9.4906        6.8393        27.94%
power10                      7.5255        5.5084        26.80%
powerpc                      9.5204        6.98055        26.68%

The performance decrease for i686 is mostly due the use of x87 fpu,
when building with '-msse2 -mfpmath=sse':

                             master        patched   improvement
latency                     140.874        77.1137        45.26%
reciprocal-throughput        64.481        56.4397        12.47%

Signed-off-by: Alexei Sibidanov <sibid@uvic.ca>
Signed-off-by: Paul Zimmermann <Paul.Zimmermann@inria.fr>
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: DJ Delorie <dj@redhat.com>
2024-11-01 11:27:39 -03:00
ChangeLog.old
advisories
argp
assert
benchtests benchtests: Add log10p1f benchmark 2024-11-01 11:17:20 -03:00
bits AArch64: Add vector logp1 alias for log1p 2024-09-19 17:53:34 +01:00
catgets
conform Disable _TIME_BITS if the compiler defaults to it 2024-10-01 08:44:41 -03:00
csu
ctype
debug stdlib: Make abort/_Exit AS-safe (BZ 26275) 2024-10-08 14:40:12 -03:00
dirent Linux: readdir64_r should not skip d_ino == 0 entries (bug 32126) 2024-09-21 19:32:34 +02:00
dlfcn
elf Revert "elf: Run constructors on cyclic recursive dlopen (bug 31986)" 2024-10-28 14:45:30 +01:00
gmon
gnulib
hesiod
htl hurd: Fix missing pthread_ compat symbol in libc 2024-08-01 23:58:51 +02:00
hurd
iconv iconv: Use $(run-program-prefix) for running iconv (bug 32197) 2024-09-24 12:35:40 +02:00
iconvdata iconv: Preserve iconv -c error exit on invalid inputs (bug 32046) 2024-09-20 13:51:09 +02:00
include stdlib: Make abort/_Exit AS-safe (BZ 26275) 2024-10-08 14:40:12 -03:00
inet Add IPPROTO_SMC from Linux 6.11 to netinet/in.h 2024-10-10 10:28:04 -03:00
intl locale: Fix some spelling typos 2024-10-14 15:38:26 +01:00
io linux: Update stat-generic.h with linux 6.11 2024-10-10 10:27:58 -03:00
libio libio: Fix crash in fputws [BZ #20632] 2024-10-25 15:05:06 -03:00
locale locale: Fix some spelling typos 2024-10-14 15:38:26 +01:00
localedata Enable transliteration rules with two input characters in scn_IT [BZ #32280] 2024-10-16 17:15:39 +02:00
login login: Re-flow and sort multiline Makefile definitions 2024-08-07 11:02:03 -03:00
mach
malloc malloc: Link threading tests with $(shared-thread-library) 2024-08-20 16:16:25 +02:00
manual Document further requirement on mixing streams / file descriptors 2024-10-28 22:22:26 +00:00
math replace tgammaf by the CORE-MATH implementation 2024-10-11 11:12:32 +02:00
mathvec
misc misc: Add support for Linux uio.h RWF_ATOMIC flag 2024-10-10 10:28:01 -03:00
nis
nptl Add more tests of pthread attributes initial values 2024-10-29 17:35:21 +00:00
nptl_db
nscd
nss nss: Fix incorrect switch fall-through in tst-nss-gai-actions 2024-08-07 15:00:25 +02:00
po
posix libio: Fix a deadlock after fork in popen 2024-10-23 13:40:16 +02:00
resolv resolv: Fix tst-resolv-short-response for older GCC (bug 32042) 2024-08-01 21:07:48 +02:00
resource
rt rt: more clock_nanosleep tests addendum 2024-10-08 14:30:21 -04:00
scripts Use Linux 6.11 in build-many-glibcs.py 2024-10-10 10:27:47 -03:00
setjmp
signal stdlib: Make abort/_Exit AS-safe (BZ 26275) 2024-10-08 14:40:12 -03:00
socket Fix name space violation in fortify wrappers (bug 32052) 2024-08-05 16:49:58 +02:00
soft-fp
stdio-common stdio-common: Fix scanf parsing for NaN types [BZ #30647] 2024-10-25 15:05:06 -03:00
stdlib stdlib: Make abort/_Exit AS-safe (BZ 26275) 2024-10-08 14:40:12 -03:00
string string: strerror, strsignal cannot use buffer after dlmopen (bug 32026) 2024-08-19 15:48:03 +02:00
sunrpc
support support: Make support_process_state_wait return the found state 2024-10-16 14:32:28 -03:00
sysdeps math: Use log10f from CORE-MATH 2024-11-01 11:27:39 -03:00
sysvipc
termios
time Link tst-clock_gettime with $(librt) 2024-10-31 17:43:52 +00:00
timezone timezone: sync to TZDB 2024b 2024-09-05 20:57:17 +00:00
wcsmbs Do not use -Wp to disable fortify (BZ 31928) 2024-10-01 08:44:40 -03:00
wctype
.b4-config Add .b4-config file 2024-10-21 14:26:42 +01:00
.clang-format
.gitattributes
.gitignore
CONTRIBUTED-BY
COPYING
COPYING.LIB
INSTALL
LICENSES
MAINTAINERS
Makeconfig Disable _TIME_BITS if the compiler defaults to it 2024-10-01 08:44:41 -03:00
Makefile
Makefile.help
Makefile.in
Makerules
NEWS stdlib: Make abort/_Exit AS-safe (BZ 26275) 2024-10-08 14:40:12 -03:00
README
Rules Implement run-built-tests=no for make xcheck, always build xtests 2024-09-21 00:29:55 +02:00
SECURITY.md
SHARED-FILES math: Use log10f from CORE-MATH 2024-11-01 11:27:39 -03:00
abi-tags
aclocal.m4
config.h.in arc: Remove HAVE_ARC_BE macro and disable big-endian port 2024-09-25 11:25:22 +02:00
config.make.in
configure Disable _TIME_BITS if the compiler defaults to it 2024-10-01 08:44:41 -03:00
configure.ac Disable _TIME_BITS if the compiler defaults to it 2024-10-01 08:44:41 -03:00
extra-lib.mk
gen-locales.mk
libc-abis
libof-iterator.mk
o-iterator.mk
shlib-versions
test-skeleton.c
version.h

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