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26b0bf9600
glibc/sysdeps/x86_64
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Joseph Myers 26b0bf9600 Avoid "inexact" exceptions in i386/x86_64 ceil functions (bug 15479). 
As discussed in
<https://sourceware.org/ml/libc-alpha/2016-05/msg00577.html>, TS
18661-1 disallows ceil, floor, round and trunc functions from raising
the "inexact" exception, in accordance with general IEEE 754 semantics
for when that exception is raised.  Fixing this for x87 floating point
is more complicated than for the other versions of these functions,
because they use the frndint instruction that raises "inexact" and
this can only be avoided by saving and restoring the whole
floating-point environment.

As I noted in
<https://sourceware.org/ml/libc-alpha/2016-06/msg00128.html>, I have
now implemented a GCC option -fno-fp-int-builtin-inexact for GCC 7,
such that GCC will inline these functions on x86, without caring about
"inexact", when the default -ffp-int-builtin-inexact is in effect.
This allows users to get optimized code depending on the options they
pass to the compiler, while making the out-of-line functions follow TS
18661-1 semantics and avoid "inexact".

This patch duly fixes the out-of-line ceil function implementations to
avoid "inexact", in the same way as the nearbyint implementations.

I do not know how the performance of implementations such as these
based on saving the environment and changing the rounding mode
temporarily compares to that of the C versions or SSE 4.1 versions (of
course, for 32-bit x86 SSE implementations still need to get the
return value in an x87 register); it's entirely possible other
implementations could be faster in some cases.

Tested for x86_64 and x86.

	[BZ #15479]
	* sysdeps/i386/fpu/s_ceil.S (__ceil): Save and restore
	floating-point environment rather than just control word.
	* sysdeps/i386/fpu/s_ceilf.S (__ceilf): Likewise.
	* sysdeps/i386/fpu/s_ceill.S (__ceill): Save and restore
	floating-point environment, with "invalid" exceptions merged in,
	rather than just control word.
	* sysdeps/x86_64/fpu/s_ceill.S (__ceill): Likewise.
	* math/libm-test.inc (ceil_test_data): Do not allow spurious
	"inexact" exceptions.
2016-06-27 17:24:30 +00:00
..
64
fpu Avoid "inexact" exceptions in i386/x86_64 ceil functions (bug 15479). 2016-06-27 17:24:30 +00:00
multiarch X86-64: Remove previous default/SSE2/AVX2 memcpy/memmove 2016-06-08 13:58:08 -07:00
nptl elf: Consolidate machine-agnostic DTV definitions in <dl-dtv.h> 2016-06-20 14:31:40 +02:00
x32 Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
____longjmp_chk.S
__longjmp.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
_mcount.S 2016-03-03 Paul Pluzhnikov <ppluzhnikov@google.com> 2016-03-03 09:53:49 -08:00
abort-instr.h
add_n.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
addmul_1.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
atomic-machine.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
backtrace.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
bsd-_setjmp.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
bsd-setjmp.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
bzero.S
configure configure: fix test == usage 2016-04-09 20:05:13 -04:00
configure.ac configure: fix test == usage 2016-04-09 20:05:13 -04:00
crti.S Replace PREINIT_FUNCTION@PLT with *%rax in call 2016-03-04 16:15:41 -08:00
crtn.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
dl-irel.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
dl-lookupcfg.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
dl-machine.h Call init_cpu_features only if SHARED is defined 2016-05-13 08:29:33 -07:00
dl-procinfo.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
dl-runtime.c
dl-tls.h elf: Consolidate machine-agnostic DTV definitions in <dl-dtv.h> 2016-06-20 14:31:40 +02:00
dl-tlsdesc.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
dl-tlsdesc.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
dl-trampoline.h [x86_64] Set DL_RUNTIME_UNALIGNED_VEC_SIZE to 8 2016-02-19 15:45:09 -08:00
dl-trampoline.S [x86_64] Set DL_RUNTIME_UNALIGNED_VEC_SIZE to 8 2016-02-19 15:45:09 -08:00
ffs.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
ffsll.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
hp-timing.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
htonl.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
ifuncmain8.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
ifuncmod8.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
Implies
jmpbuf-offsets.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
jmpbuf-unwind.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
l10nflist.c
ldbl2mpn.c
ldsodefs.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
link-defines.sym
locale-defines.sym
localplt.data
lshift.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
machine-gmon.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
Makefile Register extra test objects 2016-04-13 17:07:13 +02:00
memchr.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
memcmp.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
memcopy.h X86-64: Add dummy memcopy.h and wordcopy.c 2016-06-09 04:38:34 -07:00
memcpy_chk.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
memcpy.S X86-64: Remove previous default/SSE2/AVX2 memcpy/memmove 2016-06-08 13:58:08 -07:00
memmove_chk.S X86-64: Remove previous default/SSE2/AVX2 memcpy/memmove 2016-06-08 13:58:08 -07:00
memmove.S X86-64: Remove previous default/SSE2/AVX2 memcpy/memmove 2016-06-08 13:58:08 -07:00
mempcpy_chk.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
mempcpy.S X86-64: Remove previous default/SSE2/AVX2 memcpy/memmove 2016-06-08 13:58:08 -07:00
memrchr.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
memset_chk.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
memset.S X86-64: Remove the previous SSE2/AVX2 memsets 2016-06-08 13:56:14 -07:00
memusage.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
mp_clz_tab.c
mul_1.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
preconfigure
preconfigure.ac
rawmemchr.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
rshift.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
sched_cpucount.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
setjmp.S Call x86-64 __mcount_internal/__sigjmp_save directly 2016-03-01 16:58:07 -08:00
stack-aliasing.h
stackguard-macros.h
stackinfo.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
start.S Always indirect branch to __libc_start_main via GOT 2016-06-09 04:43:31 -07:00
stpcpy.S
strcasecmp_l-nonascii.c
strcasecmp_l.S
strcasecmp.S
strcat.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strchr.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strchrnul.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strcmp.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strcpy.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strcspn.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strlen.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strncase_l-nonascii.c
strncase_l.S
strncase.S
strncmp.S
strnlen.S
strpbrk.S
strrchr.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strspn.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
strtok_r.S
strtok.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
sub_n.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
submul_1.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
sysdep.h Avoid an extra branch to PLT for -z now 2016-05-24 08:44:23 -07:00
tls-macros.h
tlsdesc.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
tlsdesc.sym
tst-audit3.c
tst-audit4-aux.c tst-audit4, tst-audit10: Compile AVX/AVX-512 code separately [BZ #19269] 2016-03-07 16:00:25 +01:00
tst-audit4.c tst-audit4, tst-audit10: Compile AVX/AVX-512 code separately [BZ #19269] 2016-03-07 16:00:25 +01:00
tst-audit5.c
tst-audit6.c
tst-audit7.c
tst-audit10-aux.c Fix tst-audit10 build when -mavx512f is not supported. 2016-03-08 12:32:59 -08:00
tst-audit10.c tst-audit10: Fix compilation on compilers without bit_AVX512F [BZ #19860] 2016-03-25 11:11:42 +01:00
tst-audit.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
tst-auditmod3a.c
tst-auditmod3b.c
tst-auditmod4a.c
tst-auditmod4b.c
tst-auditmod5a.c
tst-auditmod5b.c
tst-auditmod6a.c
tst-auditmod6b.c
tst-auditmod6c.c
tst-auditmod7a.c
tst-auditmod7b.c
tst-auditmod10a.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
tst-auditmod10b.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
tst-mallocalign1.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
tst-quad1.c Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
tst-quad1pie.c
tst-quad2.c
tst-quad2pie.c
tst-quadmod1.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
tst-quadmod1pie.S
tst-quadmod2.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
tst-quadmod2pie.S
tst-split-dynreloc.c
tst-split-dynreloc.lds
tst-stack-align.h Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
Versions
wcschr.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
wcscmp.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
wcslen.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
wcsrchr.S Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
wordcopy.c X86-64: Add dummy memcopy.h and wordcopy.c 2016-06-09 04:38:34 -07:00