From c95a56e2a8b16eeb911eed5c1bdc8fd26f337f4d Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Thu, 24 Sep 2015 16:48:32 +0000 Subject: [PATCH] Fix x86_64 fma4 pow inappropriate contraction (bug 19003). The x86_64 fma4 version of pow fails to disable contraction of operations other than those explicitly intended to use fma instructions, so resulting in large ulps errors on processors with fma4 instructions, as in bug 18104 (165ulp for the test added for that bug; error originally reported by "blaaa" on #glibc). This patch adds $(config-cflags-nofma) for e_pow-fma4.c, corresponding to the use for e_pow.c in sysdeps/ieee754/dbl-64/Makefile. Tested for x86_64 on a processor with fma4. [BZ #19003] * sysdeps/x86_64/fpu/multiarch/Makefile (CFLAGS-e_pow-fma4.c): Add $(config-cflags-nofma). (cherry picked from commit 51df2605064a2bfd44fa0655ef9815812347de80) --- ChangeLog | 6 ++++++ NEWS | 4 ++-- sysdeps/x86_64/fpu/multiarch/Makefile | 2 +- 3 files changed, 9 insertions(+), 3 deletions(-) diff --git a/ChangeLog b/ChangeLog index 602a9676af4..6e42a1e775a 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2015-09-24 Joseph Myers + + [BZ #19003] + * sysdeps/x86_64/fpu/multiarch/Makefile (CFLAGS-e_pow-fma4.c): Add + $(config-cflags-nofma). + 2016-03-07 Hongjiu Zhang * elf/sln.c (makesymlink): Change struct stat to stat64, and lstat diff --git a/NEWS b/NEWS index 3d52bec40fd..46792587b22 100644 --- a/NEWS +++ b/NEWS @@ -24,8 +24,8 @@ Version 2.22.1 * The following bugs are resolved with this release: 17905, 18420, 18421, 18480, 18589, 18743, 18778, 18781, 18787, 18796, - 18870, 18887, 18921, 18928, 18969, 18985, 19018, 19058, 19174, 19178, - 19682. + 18870, 18887, 18921, 18928, 18969, 18985, 19003, 19018, 19058, 19174, + 19178, 19682. * The LD_POINTER_GUARD environment variable can no longer be used to disable the pointer guard feature. It is always enabled. diff --git a/sysdeps/x86_64/fpu/multiarch/Makefile b/sysdeps/x86_64/fpu/multiarch/Makefile index 86ea473b4ff..631534a5ce0 100644 --- a/sysdeps/x86_64/fpu/multiarch/Makefile +++ b/sysdeps/x86_64/fpu/multiarch/Makefile @@ -16,7 +16,7 @@ CFLAGS-e_asin-fma4.c = -mfma4 CFLAGS-e_atan2-fma4.c = -mfma4 CFLAGS-e_exp-fma4.c = -mfma4 CFLAGS-e_log-fma4.c = -mfma4 -CFLAGS-e_pow-fma4.c = -mfma4 +CFLAGS-e_pow-fma4.c = -mfma4 $(config-cflags-nofma) CFLAGS-halfulp-fma4.c = -mfma4 CFLAGS-mpa-fma4.c = -mfma4 CFLAGS-mpatan-fma4.c = -mfma4 -- 2.47.2