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Joseph Myers e02920bc02 Improve tgamma accuracy (bug 18613).
In non-default rounding modes, tgamma can be slightly less accurate
than permitted by glibc's accuracy goals.

Part of the problem is error accumulation, addressed in this patch by
setting round-to-nearest for internal computations.  However, there
was also a bug in the code dealing with computing pow (x + n, x + n)
where x + n is not exactly representable, providing another source of
error even in round-to-nearest mode; it was necessary to address both
bugs to get errors for all testcases within glibc's accuracy goals.
Given this second fix, accuracy in round-to-nearest mode is also
improved (hence regeneration of ulps for tgamma should be from scratch
- truncate libm-test-ulps or at least remove existing tgamma entries -
so that the expected ulps can be reduced).

Some additional complications also arose.  Certain tgamma tests should
strictly, according to IEEE semantics, overflow or not depending on
the rounding mode; this is beyond the scope of glibc's accuracy goals
for any function without exactly-determined results, but
gen-auto-libm-tests doesn't handle being lax there as it does for
underflow.  (libm-test.inc also doesn't handle being lax about whether
the result in cases very close to the overflow threshold is infinity
or a finite value close to overflow, but that doesn't cause problems
in this case though I've seen it cause problems with random test
generation for some functions.)  Thus, spurious-overflow markings,
with a comment, are added to auto-libm-test-in (no bug in Bugzilla
because the issue is with the testsuite, not a user-visible bug in
glibc).  And on x86, after the patch I saw ERANGE issues as previously
reported by Carlos (see my commentary in
<https://sourceware.org/ml/libc-alpha/2015-01/msg00485.html>), which
needed addressing by ensuring excess range and precision were
eliminated at various points if FLT_EVAL_METHOD != 0.

I also noticed and fixed a cosmetic issue where 1.0f was used in long
double functions and should have been 1.0L.

This completes the move of all functions to testing in all rounding
modes with ALL_RM_TEST, so gen-libm-have-vector-test.sh is updated to
remove the workaround for some functions not using ALL_RM_TEST.

Tested for x86_64, x86, mips64 and powerpc.

	[BZ #18613]
	* sysdeps/ieee754/dbl-64/e_gamma_r.c (gamma_positive): Take log of
	X_ADJ not X when adjusting exponent.
	(__ieee754_gamma_r): Do intermediate computations in
	round-to-nearest then adjust overflowing and underflowing results
	as needed.
	* sysdeps/ieee754/flt-32/e_gammaf_r.c (gammaf_positive): Take log
	of X_ADJ not X when adjusting exponent.
	(__ieee754_gammaf_r): Do intermediate computations in
	round-to-nearest then adjust overflowing and underflowing results
	as needed.
	* sysdeps/ieee754/ldbl-128/e_gammal_r.c (gammal_positive): Take
	log of X_ADJ not X when adjusting exponent.
	(__ieee754_gammal_r): Do intermediate computations in
	round-to-nearest then adjust overflowing and underflowing results
	as needed.  Use 1.0L not 1.0f as numerator of division.
	* sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (gammal_positive): Take
	log of X_ADJ not X when adjusting exponent.
	(__ieee754_gammal_r): Do intermediate computations in
	round-to-nearest then adjust overflowing and underflowing results
	as needed.  Use 1.0L not 1.0f as numerator of division.
	* sysdeps/ieee754/ldbl-96/e_gammal_r.c (gammal_positive): Take log
	of X_ADJ not X when adjusting exponent.
	(__ieee754_gammal_r): Do intermediate computations in
	round-to-nearest then adjust overflowing and underflowing results
	as needed.  Use 1.0L not 1.0f as numerator of division.
	* math/libm-test.inc (tgamma_test_data): Remove one test.  Moved
	to auto-libm-test-in.
	(tgamma_test): Use ALL_RM_TEST.
	* math/auto-libm-test-in: Add one test of tgamma.  Mark some other
	tests of tgamma with spurious-overflow.
	* math/auto-libm-test-out: Regenerated.
	* math/gen-libm-have-vector-test.sh: Do not check for START.
	* sysdeps/i386/fpu/libm-test-ulps: Update.
	* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
2015-06-29 23:29:35 +00:00
argp Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
assert Add ersatz _Static_assert on older C hosts 2015-02-07 14:43:27 -08:00
benchtests Fix benchtests build failure after 'add benchmark for strcoll' 2015-06-19 13:47:59 +02:00
bits Vector sincos for x86_64 and tests. 2015-06-18 17:55:55 +03:00
catgets Update copyright dates not handled by scripts/update-copyrights. 2015-01-02 16:54:45 +00:00
conf (NEED_INETADDR, NEED_INETATON): Define to 1, not empty. 1995-09-08 20:24:57 +00:00
conform conformtest: Fix pselect expectations. 2015-06-19 20:52:44 +00:00
crypt Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
csu Align TCB offset to the maximum alignment 2015-06-24 16:30:58 -07:00
ctype Fix isblank / isascii / toascii namespace (bug 17635). 2015-01-05 15:06:57 +00:00
debug Let tests result in UNSUPPORTED; use that for unbuildable C++ cases 2015-03-10 15:13:14 -07:00
dirent Nit fixes in last change. 2015-05-13 12:39:01 -07:00
dlfcn Convert dlfcn/tststatic to use test-skeleton. 2015-03-27 12:55:25 -07:00
elf Add support for DT_MIPS_RLD_MAP_REL. 2015-06-26 12:03:45 +01:00
gmon Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
gnulib Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
grp Fix grp.h endgrent, getgrent namespace (bug 18528). 2015-06-12 22:29:19 +00:00
gshadow Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
hesiod Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
hurd Fix warnings 2015-03-21 04:49:44 +01:00
iconv Convert tst-iconv3 to use test-skeleton. 2015-02-25 16:01:13 -08:00
iconvdata Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
include Remove include/bits/ipc.h. 2015-06-18 23:08:15 +00:00
inet Fix gethostbyaddr in6addr_any, in6addr_loopback namespace (bug 18532). 2015-06-17 20:08:22 +00:00
intl Remove obsolete aliases that broke 'locale -a' 2015-05-22 15:12:01 -07:00
io posix_fallocate, posix_fallocate64 stub: Do not set errno 2015-04-24 20:08:43 +02:00
libidn Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
libio Fix buffer overflow for writes to memory buffer stream (bug 18549) 2015-06-25 15:54:09 +02:00
locale Remove unused PREDEFINED_CLASSES code 2015-06-09 09:34:06 +02:00
localedata Fix sorting order for Ukrainian locale (BZ 17293) 2015-05-26 23:51:18 +05:30
login Fix getlogin_r namespace (bug 18527). 2015-06-12 20:02:30 +00:00
mach mach: fix typo 2015-06-06 11:48:42 +02:00
malloc malloc: Do not corrupt the top of a threaded heap if top chunk is MINSIZE [BZ #18502] 2015-06-26 22:47:45 +02:00
manual Attempting to install glibc configured with --prefix=/usr into 2015-06-12 13:15:57 -06:00
math Improve tgamma accuracy (bug 18613). 2015-06-29 23:29:35 +00:00
mathvec This is update for configure, build and install of vector math library. 2015-05-14 18:07:06 +03:00
misc Fix ttyslot namespace (bug 18547). 2015-06-17 20:21:19 +00:00
nis Separate internal state between getXXent and getXXbyYY NSS calls (bug 18007) 2015-05-11 10:41:49 +02:00
nptl NPTL: Use unsigned type for setxid_futex. 2015-06-24 18:09:32 -07:00
nptl_db Fix DTV race, assert, DTV_SURPLUS Static TLS limit, and nptl_db garbage 2015-03-17 00:31:49 -03:00
nscd nscd_getgr_r: Use struct scratch_buffer instead of extend_alloca 2015-04-08 21:08:03 +02:00
nss Separate internal state between getXXent and getXXbyYY NSS calls (bug 18007) 2015-05-11 10:41:49 +02:00
po glibc 2.21 pre-release update. 2015-02-05 23:14:38 -05:00
posix Fix getlogin_r namespace (bug 18527). 2015-06-12 20:02:30 +00:00
pwd tst-getpw: Rewrite. 2015-01-21 10:08:18 -05:00
resolv Use unsigned types for counters in getaddrinfo_a code. 2015-06-24 17:58:12 -07:00
resource Fix nice getpriority, setpriority namespace (bug 18553). 2015-06-17 20:22:39 +00:00
rt Fix mq_receive, mq_send mq_timed* namespace (bug 18545). 2015-06-17 20:19:04 +00:00
scripts Add more exception to local headers list 2015-03-23 00:31:02 +01:00
setjmp Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
shadow Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
signal Fix psignal, psiginfo declaration conditions (bug 18483). 2015-06-05 21:14:16 +00:00
socket Fix mq_notify socket, recv namespace (bug 18546). 2015-06-17 20:20:08 +00:00
soft-fp Fix soft-fp fma for -Wuninitialized. 2015-05-22 20:28:50 +00:00
stdio-common Fix syslog dprintf namespace (bug 18534). 2015-06-17 20:10:50 +00:00
stdlib Fix fmtmsg addseverity namespace (bug 18539). 2015-06-17 20:13:07 +00:00
streams Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
string remove unnecessary memset in strcoll 2015-06-22 07:53:09 +05:30
sunrpc Use calloc to allocate xports (BZ #17542) 2015-03-18 14:51:26 +05:30
sysdeps Improve tgamma accuracy (bug 18613). 2015-06-29 23:29:35 +00:00
sysvipc Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
termios Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
time Check tzspec_len == 0 in __tzfile_read 2015-04-27 09:57:51 -07:00
timezone Fix timezone tests run in parallel. 2015-06-19 13:47:59 +02:00
wcsmbs Fix regcomp wcscoll, wcscmp namespace (bug 18497). 2015-06-09 21:07:30 +00:00
wctype Fix regex wctype namespace (bug 18495). 2015-06-05 20:04:47 +00:00
.gitattributes exempt timezone files from the no-bad-whitespace policy 2009-06-15 18:15:54 +02:00
.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 Make aclocal.m4 comment mention updating install.texi for autoconf version. 2014-10-31 22:44:17 +00:00
BUGS [BZ #5222] 2007-10-28 08:24:07 +00:00
ChangeLog Improve tgamma accuracy (bug 18613). 2015-06-29 23:29:35 +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 Update. 1997-07-22 00:10:33 +00:00
ChangeLog.7 Update. 1997-11-18 02:50:07 +00:00
ChangeLog.8 Update. Old logs are in ChangeLog.7. 1998-08-11 18:44:11 +00:00
ChangeLog.9 Update. 2000-04-28 06:14:43 +00:00
ChangeLog.10 Update. 2000-02-29 01:13:44 +00:00
ChangeLog.11 2.5-18.1 2007-07-12 18:26:36 +00:00
ChangeLog.12 2.5-18.1 2007-07-12 18:26:36 +00:00
ChangeLog.13 Update. 2002-10-03 16:37:04 +00:00
ChangeLog.14 Update. 2004-04-20 04:28:00 +00:00
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
ChangeLog.old-ports-aarch64 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-aix Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-alpha Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-am33 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
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 [AArch64] Fix the big endian loader name. 2015-05-01 13:58:55 +01:00
config.make.in Support compilers defaulting to PIE 2015-06-25 02:49:53 -07:00
configure Support compilers defaulting to PIE 2015-06-25 02:49:53 -07:00
configure.ac Support compilers defaulting to PIE 2015-06-25 02:49:53 -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 Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
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 Attempting to install glibc configured with --prefix=/usr into 2015-06-12 13:15:57 -06:00
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 Support compilers defaulting to PIE 2015-06-25 02:49:53 -07:00
Makefile Succeed if make check does not report any errors 2015-05-19 06:36:29 +05:30
Makefile.in Remove redundant C locale settings. 2014-06-07 19:58:36 +00:00
Makerules Attempting to install glibc configured with --prefix=/usr into 2015-06-12 13:15:57 -06:00
NAMESPACE Add and update many more entries. 2000-03-20 00:42:58 +00:00
NEWS Improve tgamma accuracy (bug 18613). 2015-06-29 23:29:35 +00:00
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
PROJECTS Update. 2004-10-12 06:19:23 +00:00
README Another pointless update in README. 2015-02-11 14:39:30 -08:00
Rules Let tests result in UNSUPPORTED; use that for unbuildable C++ cases 2015-03-10 15:13:14 -07:00
shlib-versions This is update for configure, build and install of vector math library. 2015-05-14 18:07:06 +03:00
test-skeleton.c Avoid outputting to TTY after an expected memory corruption in testcase 2015-06-05 09:39:49 -03:00
version.h Open development for 2.22. 2015-02-06 02:03:41 -05:00
WUR-REPORT * posix/unistd.h (setuid, setreuid, seteuid, setresuid): 2012-08-01 18:12:58 +02:00

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