glibc/sysdeps
Joseph Myers 5146356f5a Add fesetexcept.
TS 18661-1 defines an fesetexcept function for setting floating-point
exception flags without the side-effect of causing enabled traps to be
taken.

This patch series implements this function for glibc.  The present
patch adds the fallback stub implementation, x86 and x86_64
implementations, documentation, tests and ABI baseline updates.  The
remaining patches, some of them untested, add implementations for
other architectures.  The implementations generally follow those of
the fesetexceptflag function.

As for fesetexceptflag, the approach taken for architectures where
setting flags causes enabled traps to be taken is to set the flags
(and potentially cause traps) rather than refusing to set the flags
and returning an error.  Since ISO C and TS 18661 provide no way to
enable traps, this is formally in accordance with the standards.

The NEWS entry should be considered a placeholder, since this patch
series is intended to be followed by further such series adding other
TS 18661-1 features, so that the NEWS entry would end up looking more
like

* New <fenv.h> features from TS 18661-1:2014 are added to libm: the
  fesetexcept, fetestexceptflag, fegetmode and fesetmode functions,
  the femode_t type and the FE_DFL_MODE macro.

with hopefully more such entries for other features, rather than
having an entry for a single function in the end.

I believe we have consensus for adding TS 18661-1 interfaces as per
<https://sourceware.org/ml/libc-alpha/2016-06/msg00421.html>.

Tested for x86_64, x86, mips64 (hard float, and soft float to test the
fallback version), arm (hard float) and powerpc (hard float, soft
float and e500).

	* math/fesetexcept.c: New file.
	* sysdeps/i386/fpu/fesetexcept.c: Likewise.
	* sysdeps/x86_64/fpu/fesetexcept.c: Likewise.
	* math/fenv.h: Define
	__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
	<bits/libc-header-start.h> instead of including <features.h>.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (fesetexcept): New function
	declaration.
	* manual/arith.texi (fesetexcept): Document function.
	* math/Versions (fesetexcept): New libm symbol at version
	GLIBC_2.25.
	* math/Makefile (libm-support): Add fesetexcept.
	(tests): Add test-fesetexcept and test-fesetexcept-traps.
	* math/test-fesetexcept.c: New file.
	* math/test-fesetexcept-traps.c: Likewise.
	* sysdeps/nacl/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
2016-08-16 16:16:10 +00:00
..
aarch64 [AArch64] Update libm-test-ulps 2016-07-21 09:48:45 +01:00
alpha alpha: fix trunc for big input values 2016-08-02 09:18:59 +02:00
arm Minimize sysdeps code involved in defining major/minor/makedev. 2016-08-03 15:23:04 -04:00
generic Add tests for fegetexceptflag, fesetexceptflag. 2016-08-10 21:01:08 +00:00
gnu Define UDP_ENCAP_* from Linux 4.7 in netinet/udp.h. 2016-08-03 12:13:16 +00:00
hppa hppa: Update libm-test-ulps. 2016-07-06 14:45:23 +02:00
i386 Add fesetexcept. 2016-08-16 16:16:10 +00:00
ia64 elf: Consolidate machine-agnostic DTV definitions in <dl-dtv.h> 2016-06-20 14:31:40 +02:00
ieee754 Remove tacit double usage in ldbl-128 2016-08-03 11:01:25 -05:00
init_array Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
m68k m68k: suppress -Wframe-address warning 2016-07-04 23:15:29 +02:00
mach Fix recvmsg returning SIGLOST on PF_LOCAL sockets 2016-08-09 01:42:50 +02:00
microblaze Remove atomic_compare_and_exchange_bool_rel. 2016-06-24 23:04:40 +03:00
mips MIPS: run tst-mode-switch-{1,2,3}.c using test-skeleton.c 2016-06-27 23:57:40 +02:00
nacl Add fesetexcept. 2016-08-16 16:16:10 +00:00
nios2 elf: Consolidate machine-agnostic DTV definitions in <dl-dtv.h> 2016-06-20 14:31:40 +02:00
nptl Increase fork signal safety for single-threaded processes [BZ #19703] 2016-05-12 15:26:55 +02:00
posix getaddrinfo: Convert from extend_alloca to struct scratch_buffer 2016-05-12 14:07:56 +02:00
powerpc Add comment from sysdeps/powerpc/fpu/fraiseexcpt.c to fsetexcptflg.c. 2016-08-12 17:49:07 +00:00
pthread Revert "aio: fix newp->running data race" 2016-05-04 15:52:30 +02:00
s390 S390: Do not clobber r13 with memcpy on 31bit with copies >1MB. 2016-07-20 08:29:43 +02:00
sh elf: Consolidate machine-agnostic DTV definitions in <dl-dtv.h> 2016-06-20 14:31:40 +02:00
sparc sparc32/sparcv9: add a VIS3 version of fdim 2016-08-05 22:35:01 +02:00
tile Remove atomic_compare_and_exchange_bool_rel. 2016-06-24 23:04:40 +03:00
unix Add fesetexcept. 2016-08-16 16:16:10 +00:00
wordsize-32 Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
wordsize-64 Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
x86 Fixed wrong vector sincos/sincosf ABI to have it compatible with 2016-07-01 14:15:38 +03:00
x86_64 Add fesetexcept. 2016-08-16 16:16:10 +00:00