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Joseph Myers e4e52ff059 Improve float range reduction accuracy near pi/2 (bug 21094).
Bug 21094 reports 3ulp errors of cosf and tanf for certain arguments
near pi/2 arising from the use of an insufficiently accurate range
reduction.  (To be clear, this is a quality-of-implementation issue
relating to the apparent intent of those particular cosf and tanf
implementations; 3ulp is within the general glibc accuracy goals, so
not inherently a bug.)

This patch fixes that error by making a wider range of cases use the
existing more accurate range reduction for arguments close to pi/2.
The wider range of values is still narrow enough for the "z -=
pio2_2;" in the more accurate case to be exact, as the code expects.

Tested for x86_64, x86 and mips64; no ulps updates needed (but at
least on mips64, the larger ulps were seen if the tests were added
without the substantive fix).

	[BZ #21094]
	* sysdeps/ieee754/flt-32/e_rem_pio2f.c (__ieee754_rem_pio2f): Use
	24+24+24-bit pi for wider range of values around pi/2.
	* math/auto-libm-test-in: Add more tests of cos and tan.
	* math/auto-libm-test-out-cos: Regenerated.
	* math/auto-libm-test-out-tan: Likewise.
2017-03-15 22:00:54 +00:00
argp Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
assert Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
benchtests Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
bits Refer to <signal.h> instead of <pthread.h> in <bits/sigthread.h> 2017-02-28 10:34:15 +01:00
catgets Update copyright dates not handled by scripts/update-copyrights. 2017-01-01 00:26:24 +00:00
conform Fix missing test dependency 2017-02-01 17:40:56 +01:00
crypt Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
csu Update copyright dates not handled by scripts/update-copyrights. 2017-01-01 00:26:24 +00:00
ctype Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
debug Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
dirent Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
dlfcn Miscellaneous low-risk changes preparing for _ISOMAC testsuite. 2017-03-01 20:32:50 -05:00
elf Remove the str(n)dup inlines from string/bits/string2.h. Although inlining 2017-03-13 18:45:42 +00:00
gmon Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
gnulib Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
grp Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
gshadow Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
hesiod Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
hurd As a minor cleanup remove the (r)index defines from include/string.h as 2017-02-06 18:15:18 +00:00
iconv Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
iconvdata Document and fix --enable-bind-now [BZ #21015] 2017-03-02 14:44:28 +01:00
include Split helper classification macros from mathcalls.h 2017-03-15 09:39:16 -03:00
inet Remove the str(n)dup inlines from string/bits/string2.h. Although inlining 2017-03-13 18:45:42 +00:00
intl Remove the str(n)dup inlines from string/bits/string2.h. Although inlining 2017-03-13 18:45:42 +00:00
io Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
libidn Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
libio Clean up conditionals for declaration of gets. 2017-02-25 09:47:51 -05:00
locale Remove the str(n)dup inlines from string/bits/string2.h. Although inlining 2017-03-13 18:45:42 +00:00
localedata Bug 20313: Update to Unicode 9.0.0 2017-02-21 06:30:38 -05:00
login Update copyright dates not handled by scripts/update-copyrights. 2017-01-01 00:26:24 +00:00
mach Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
malloc Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
manual timezone: Remove TZNAME_MAX limit from sysconf [BZ #15576] 2017-03-07 17:45:38 +01:00
math Improve float range reduction accuracy near pi/2 (bug 21094). 2017-03-15 22:00:54 +00:00
mathvec Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
misc Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
nis Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
nptl Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
nptl_db Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
nscd Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
nss Fix build with --enable-static-nss [BZ #21088] 2017-03-15 13:32:23 -07:00
po Add target to incorporate translations from translations.org 2017-01-20 12:32:46 +05:30
posix Fix test-errno issues 2017-03-15 17:05:34 -03:00
pwd Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
resolv Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
resource Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
rt One more obvious missing #include in the testsuite. 2017-02-19 10:29:34 -05:00
scripts build-many-glibcs: Remove no_isolate from SH config 2017-03-13 16:23:25 -03:00
setjmp Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
shadow Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
signal Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
socket Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
soft-fp Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
stdio-common Narrowing the visibility of libc-internal.h even further. 2017-03-01 20:33:46 -05:00
stdlib Remove the str(n)dup inlines from string/bits/string2.h. Although inlining 2017-03-13 18:45:42 +00:00
streams Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
string Remove the str(n)dup inlines from string/bits/string2.h. Although inlining 2017-03-13 18:45:42 +00:00
sunrpc Remove the str(n)dup inlines from string/bits/string2.h. Although inlining 2017-03-13 18:45:42 +00:00
support support: Explain ignored failures of temporary file removal [BZ #21243] 2017-03-15 13:33:40 +01:00
sysdeps Improve float range reduction accuracy near pi/2 (bug 21094). 2017-03-15 22:00:54 +00:00
sysvipc Fix test-sysvsem on some platforms 2017-01-02 18:53:50 -02:00
termios Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
time tzset: Clean up preprocessor macros min, max, sign 2017-03-07 17:45:39 +01:00
timezone Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
wcsmbs Split DIAG_* macros to new header libc-diag.h. 2017-02-25 09:59:46 -05:00
wctype Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
.gitattributes Assume __NR_openat is always defined 2016-03-23 23:35:08 +01:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
abi-tags Add arm-nacl port. 2015-04-17 09:02:19 -07:00
aclocal.m4 Work even with compilers which enable -fstack-protector by default [BZ #7065] 2016-12-26 10:10:58 +01:00
BUGS [BZ #5222] 2007-10-28 08:24:07 +00:00
ChangeLog Improve float range reduction accuracy near pi/2 (bug 21094). 2017-03-15 22:00:54 +00:00
ChangeLog.1 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.2 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.3 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.4 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.5 * sysdeps/posix/getaddrinfo.c: Implement configuration file 2006-05-04 06:38:07 +00:00
ChangeLog.6 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.7 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.8 ChangeLog: change Winblowz to Windows 2016-08-10 00:49:28 +08:00
ChangeLog.9 Update. 2000-04-28 06:14:43 +00:00
ChangeLog.10 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.11 ChangeLog: change Winblowz to Windows 2016-08-10 00:49:28 +08:00
ChangeLog.12 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.13 Update. 2002-10-03 16:37:04 +00:00
ChangeLog.14 Revert "ChangeLogs: convert to utf-8" 2016-02-12 16:35:27 -05:00
ChangeLog.15 Split out ChangeLog.15 at 2.3 branch point 2005-02-16 07:34:17 +00:00
ChangeLog.16 Fix typo in name 2012-06-21 16:45:27 +02:00
ChangeLog.17 Revert "Sun agreed to a change of the license for the RPC code to a BSD-like license." 2010-06-27 19:34:03 -07:00
ChangeLog.old-ports Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
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ChangeLog.old-ports-aix Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
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ChangeLog.old-ports-arm Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-cris Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-hppa Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-ia64 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-linux-generic Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-m68k Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-microblaze Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-mips Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-powerpc Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-tile Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
config.h.in Rework -fno-omit-frame-pointer support on i386 2017-02-17 18:06:29 -02:00
config.make.in Initialize tunable list with the GLIBC_TUNABLES environment variable 2016-12-31 23:49:24 +05:30
configure Fix combreloc test with BSD grep 2017-03-15 13:26:13 -07:00
configure.ac Fix combreloc test with BSD grep 2017-03-15 13:26:13 -07:00
CONFORMANCE Move __STDC_* predefined macros from features.h to stdc-predef.h. 2012-02-22 12:53:04 +00:00
COPYING Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
COPYING.LIB Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
cppflags-iterator.mk 2004-03-11 Jeroen Dekkers <jeroen@dekkers.cx> 2004-03-14 19:13:17 +00:00
extra-lib.mk support: Introduce new subdirectory for test infrastructure 2016-12-09 08:18:27 +01:00
extra-modules.mk Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
gen-locales.mk Split locale generation snippet into a separate file 2015-05-13 13:05:28 +05:30
INSTALL Document and fix --enable-bind-now [BZ #21015] 2017-03-02 14:44:28 +01:00
libc-abis A few more archs have IFUNC support. 2010-03-17 02:43:12 -07:00
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
Makeconfig Document and fix --enable-bind-now [BZ #21015] 2017-03-02 14:44:28 +01:00
Makefile Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
Makefile.in New make target to only build benchmark binaries 2016-04-20 10:23:28 +05:30
Makerules Document and fix --enable-bind-now [BZ #21015] 2017-03-02 14:44:28 +01:00
NAMESPACE Add and update many more entries. 2000-03-20 00:42:58 +00:00
NEWS If sunrpc code is disabled, rpcsvc header files, rpcgen and 2017-03-11 11:36:58 +01:00
o-iterator.mk Fri Mar 17 12:58:37 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu> 1995-03-17 18:42:51 +00:00
README Require Linux 3.2 except on x86 / x86_64, 3.2 headers everywhere. 2016-02-24 17:15:12 +00:00
README.pretty-printers Fix mutex pretty printer test and pretty printer output. 2017-01-20 14:56:39 +01:00
README.tunables Add framework for tunables 2016-12-31 23:49:24 +05:30
Rules Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
shlib-versions This is update for configure, build and install of vector math library. 2015-05-14 18:07:06 +03:00
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version.h Open master for development 2017-02-05 21:27:52 +05:30
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