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Joseph Myers 43059f42db soft-fp: Make extensions of subnormals from XFmode to TFmode signal underflow if traps enabled.
This patch fixes a soft-fp corner case I previously noted in
<https://sourceware.org/ml/libc-alpha/2013-10/msg00349.html>: when
trapping on underflow is enabled, extensions of subnormals from XFmode
to TFmode need to signal underflow because the result is tiny (but
exact, so the underflow flag is not raised unless trapping is
enabled).

To avoid any excess initialization or tests for other cases of
floating-point extensions, a new FP_INIT_TRAPPING_EXCEPTIONS is added
that does the initialization required for this particular case (more
than FP_INIT_EXCEPTIONS, less than FP_INIT_ROUNDMODE, in general), and
FP_NO_EXACT_UNDERFLOW is added to stub out FP_TRAPPING_EXCEPTIONS
tests for those cases of extensions where the test would be dead code,
to avoid any uninitialized variable warnings.

As the relevant case only applies in libgcc, not to any use of soft-fp
in glibc, there is no bug report in Bugzilla and no non-default
definitions of FP_INIT_TRAPPING_EXCEPTIONS are added by the patch.  A
testcase will be added to GCC as part of an update of soft-fp in
libgcc once this patch is in libc.

Tested for powerpc-nofpu that the disassembly of installed shared
libraries is unchanged by this patch.  Bootstrapped GCC with updated
soft-fp with no regressions on x86_64-unknown-linux-gnu and verified
that a test of the relevant case passes where it failed before.

	* soft-fp/op-common.h (FP_EXTEND): When a subnormal input produces
	a subnormal result, set the underflow exception if trapping on
	underflow is enabled.
	* soft-fp/soft-fp.h (FP_INIT_TRAPPING_EXCEPTIONS): New macro.
	(FP_INIT_EXCEPTIONS): Default to FP_INIT_TRAPPING_EXCEPTIONS.
	[FP_NO_EXACT_UNDERFLOW] (FP_TRAPPING_EXCEPTIONS): Undefine and
	redefine to 0.
	* soft-fp/extenddftf2.c (FP_NO_EXACT_UNDERFLOW): Define.
	* soft-fp/extendsfdf2.c (FP_NO_EXACT_UNDERFLOW): Likewise.
	* soft-fp/extendsftf2.c (FP_NO_EXACT_UNDERFLOW): Likewise.
	* soft-fp/extendxftf2.c (__extendxftf2): Use
	FP_INIT_TRAPPING_EXCEPTIONS instead of FP_INIT_ROUNDMODE.
2014-10-09 01:00:41 +00:00
argp Fix __STRICT_ANSI__ -Wundef warnings 2014-03-17 16:05:23 +00:00
assert Remove redundant C locale settings. 2014-06-07 19:58:36 +00:00
benchtests PowerPC: memset optimization for POWER8/PPC64 2014-09-10 07:39:46 -04:00
bits Fix -Wundef for _UTSNAME_DOMAIN_LENGTH. 2014-05-08 10:47:35 -07:00
catgets Remove redundant CPPFLAGS for some programs 2014-08-21 10:27:13 +05:30
conf
conform conformtest: clean up POSIX expectations for sys/mman.h, sys/stat.h, sys/types.h. 2014-06-11 23:16:23 +00:00
crypt crypt: don't include ufc-crypt.h multiple times 2014-06-06 18:25:31 -04:00
csu Remove bitrotten --enable-oldest-abi (bug 6652). 2014-09-16 17:45:03 +00:00
ctype Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
debug Fix -Wundef warning on PAGE_COPY_THRESHOLD 2014-07-03 01:49:43 +05:30
dirent Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
dlfcn Include .interp section only for libc.so 2014-09-16 22:19:22 +05:30
elf Remove unnecessarily nested function in do_lookup_unique. 2014-10-08 15:18:02 -07:00
gmon Don't use catomic functions in mcount (BZ #16912) 2014-05-06 16:30:48 +02:00
gnulib Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
grp Enumerate tests with special rules in tests-special variable. 2014-03-06 22:35:33 +00:00
gshadow Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
hesiod Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
hurd Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
iconv Complete the removal of __gconv_translit_find 2014-09-12 09:17:32 +02:00
iconvdata CVE-2014-6040: Crashes on invalid input in IBM gconv modules [BZ #17325] 2014-09-03 19:46:42 +02:00
include Update version.h and include/features.h for 2.20 release 2014-09-07 18:09:09 +10:00
inet Return failure in getnetgrent only when all netgroups have been searched (#17363) 2014-09-10 21:51:50 +05:30
intl tst-gettext2: make setup more robust 2014-08-08 22:55:48 -04:00
io Fix -Wundef warning for HAVE_SYS_PARAM_H 2014-07-10 14:19:21 +05:30
libidn Remove configuration name patterns from shlib-versions. 2014-09-12 12:28:47 +00:00
libio Fix memory leak in error path of do_ftell_wide (BZ #17370) 2014-09-16 14:20:45 +05:30
locale Minor cleanup in locale.c 2014-09-12 16:07:23 -07:00
localedata Allow cross-building of tests 2014-09-30 15:02:41 +01:00
login ptsname_r: don't leak uninitialized memory (BZ #16917) 2014-05-16 00:07:29 +02:00
mach Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
malloc malloc: additional unlink hardening for non-small bins [BZ #17344] 2014-09-11 10:59:05 +02:00
manual Update contrib.texi 2014-09-07 16:07:10 +10:00
math stdlib/tst-strtod-round.c: Fix build on ARM 2014-09-30 15:03:50 +01:00
misc Make __extern_always_inline usable on clang++ again 2014-09-16 22:16:01 +05:30
nis Fix unbound stack use in NIS NSS module 2014-05-12 15:17:51 +02:00
nptl Write errors to stdout and not stderr in nptl/tst-setuid3.c 2014-10-06 10:23:17 +05:30
nptl_db Remove configuration name patterns from shlib-versions. 2014-09-12 12:28:47 +00:00
nscd BZ#17460: Fix buffer overrun in nscd --help. 2014-10-08 15:36:12 -07:00
nss Remove stray includes of kernel-features.h. 2014-06-25 18:09:01 +00:00
po Update Russian translation 2014-09-13 15:41:54 +10:00
posix Assume that all _[PS]C_* and _CS_* macros are always defined 2014-09-16 22:18:20 +05:30
pwd Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
resolv Check value at resplen2 if it is not NULL 2014-07-08 22:52:49 +05:30
resource Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
rt Fix -Wundef warning for HAVE_IFUNC 2014-07-31 17:05:19 +02:00
scripts Clean up gnu/lib-names.h generation (bug 14171). 2014-09-26 17:33:04 +00:00
setjmp Use existing makefile variables for dependencies on glibc libraries. 2014-05-16 21:38:08 +00:00
shadow Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
signal Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
socket Sync recvmmsg prototype with kernel usage. 2014-09-20 13:53:44 +02:00
soft-fp soft-fp: Make extensions of subnormals from XFmode to TFmode signal underflow if traps enabled. 2014-10-09 01:00:41 +00:00
stdio-common remove nested function hack_digit 2014-09-29 10:46:05 -07:00
stdlib stdlib/tst-strtod-round.c: Fix build on ARM 2014-09-30 15:03:50 +01:00
streams Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
string Move findidx nested functions to top-level. 2014-09-11 16:02:17 -07:00
sunrpc Add comment about SIZE initialization in xdr.c 2014-07-10 10:33:48 +05:30
sysdeps soft-fp: Remove FP_CLEAR_EXCEPTIONS. 2014-10-09 00:58:42 +00:00
sysvipc Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
termios Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
time New test for ftime 2014-09-18 13:26:53 +05:30
timezone Allow cross-building of tests 2014-09-30 15:02:41 +01:00
wcsmbs Complete the removal of __gconv_translit_find 2014-09-12 09:17:32 +02:00
wctype Consistently include Makeconfig after defining subdir. 2014-02-26 23:12:03 +00:00
.gitattributes exempt timezone files from the no-bad-whitespace policy 2009-06-15 18:15:54 +02:00
.gitignore ignore gdb related files 2013-12-27 16:30:50 -05:00
abi-tags * abi-tags (*-.*-syllable.*): New match, with ABI value 5. 2006-01-04 17:14:58 +00:00
aclocal.m4 Require autoconf 2.69 2014-09-29 07:53:36 -07:00
BUGS [BZ #5222] 2007-10-28 08:24:07 +00:00
CANCEL-FCT-WAIVE Update. 2004-03-08 07:58:18 +00:00
CANCEL-FILE-WAIVE Update. 2004-03-08 07:58:18 +00:00
ChangeLog soft-fp: Make extensions of subnormals from XFmode to TFmode signal underflow if traps enabled. 2014-10-09 01:00:41 +00:00
ChangeLog.1
ChangeLog.2
ChangeLog.3
ChangeLog.4
ChangeLog.5 * sysdeps/posix/getaddrinfo.c: Implement configuration file 2006-05-04 06:38:07 +00:00
ChangeLog.6
ChangeLog.7
ChangeLog.8
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 Remove bitrotten --enable-oldest-abi (bug 6652). 2014-09-16 17:45:03 +00:00
config.make.in Remove bitrotten --enable-oldest-abi (bug 6652). 2014-09-16 17:45:03 +00:00
configure Require autoconf 2.69 2014-09-29 07:53:36 -07:00
configure.ac Remove bitrotten --enable-oldest-abi (bug 6652). 2014-09-16 17:45:03 +00:00
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 --disable-versioning. 2013-09-04 15:25:42 +00:00
extra-modules.mk Update. 2004-03-08 21:31:23 +00:00
INSTALL Remove redundant C locale settings. 2014-06-07 19:58:36 +00:00
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 Clean up gnu/lib-names.h generation (bug 14171). 2014-09-26 17:33:04 +00:00
Makefile Fix pthread.h in installed-headers list. 2014-06-13 16:39:23 -07:00
Makefile.in Remove redundant C locale settings. 2014-06-07 19:58:36 +00:00
Makerules Clean up gnu/lib-names.h generation (bug 14171). 2014-09-26 17:33:04 +00:00
NAMESPACE Add and update many more entries. 2000-03-20 00:42:58 +00:00
NEWS BZ#17460: Fix buffer overrun in nscd --help. 2014-10-08 15:36:12 -07:00
o-iterator.mk
PROJECTS Update. 2004-10-12 06:19:23 +00:00
README Update README and NEWS for ports directory removal. 2014-06-25 12:55:21 +00:00
Rules Don't require test wrappers to preserve environment variables, use more consistent environment. 2014-06-06 22:19:27 +00:00
shlib-versions Remove configuration name patterns from shlib-versions. 2014-09-12 12:28:47 +00:00
test-skeleton.c test-skeleton: Kill any child process's offspring 2014-06-30 20:11:56 +01:00
version.h Open development for 2.21 2014-09-08 09:22:55 +10:00
WUR-REPORT * posix/unistd.h (setuid, setreuid, seteuid, setresuid): 2012-08-01 18:12:58 +02:00

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