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Joseph Myers d8742dd82f Add narrowing add functions.
This patch adds the narrowing add functions from TS 18661-1 to glibc's
libm: fadd, faddl, daddl, f32addf64, f32addf32x, f32xaddf64 for all
configurations; f32addf64x, f32addf128, f64addf64x, f64addf128,
f32xaddf64x, f32xaddf128, f64xaddf128 for configurations with
_Float64x and _Float128; __nldbl_daddl for ldbl-opt.  As discussed for
the build infrastructure patch, tgmath.h support is deliberately
deferred, and FP_FAST_* macros are not applicable without optimized
function implementations.

Function implementations are added for all relevant pairs of formats
(including certain cases of a format and itself where more than one
type has that format).  The main implementations use round-to-odd, or
a trivial computation in the case where both formats are the same or
where the wider format is IBM long double (in which case we don't
attempt to be correctly rounding).  The sysdeps/ieee754/soft-fp
implementations use soft-fp, and are used automatically for
configurations without exceptions and rounding modes by virtue of
existing Implies files.  As previously discussed, optimized versions
for particular architectures are possible, but not included.

i386 gets a special version of f32xaddf64 to avoid problems with
double rounding (similar to the existing fdim version), since this
function must round just once without an intermediate rounding to long
double.  (No such special version is needed for any other function,
because the nontrivial functions use round-to-odd, which does the
intermediate computation with the rounding mode set to round-to-zero,
and double rounding is OK except in round-to-nearest mode, so is OK
for that intermediate round-to-zero computation.)  mul and div will
need slightly different special versions for i386 (using round-to-odd
on long double instead of precision control) because of the
possibility of inexact intermediate results in the subnormal range for
double.

To reduce duplication among the different function implementations,
math-narrow.h gets macros CHECK_NARROW_ADD, NARROW_ADD_ROUND_TO_ODD
and NARROW_ADD_TRIVIAL.

In the trivial cases and for any architecture-specific optimized
implementations, the overhead of the errno setting might be
significant, but I think that's best handled through compiler built-in
functions rather than providing separate no-errno versions in glibc
(and likewise there are no __*_finite entry points for these function
provided, __*_finite effectively being no-errno versions at present in
most cases).

Tested for x86_64 and x86, with both GCC 6 and GCC 7.  Tested for
mips64 (all three ABIs, both hard and soft float) and powerpc with GCC
7.  Tested with build-many-glibcs.py with both GCC 6 and GCC 7.

	* math/Makefile (libm-narrow-fns): Add add.
	(libm-test-funcs-narrow): Likewise.
	* math/Versions (GLIBC_2.28): Add narrowing add functions.
	* math/bits/mathcalls-narrow.h (add): Use __MATHCALL_NARROW .
	* math/gen-auto-libm-tests.c (test_functions): Add add.
	* math/math-narrow.h (CHECK_NARROW_ADD): New macro.
	(NARROW_ADD_ROUND_TO_ODD): Likewise.
	(NARROW_ADD_TRIVIAL): Likewise.
	* sysdeps/ieee754/float128/float128_private.h (__faddl): New
	macro.
	(__daddl): Likewise.
	* sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add fadd and
	dadd.
	(CFLAGS-nldbl-dadd.c): New variable.
	(CFLAGS-nldbl-fadd.c): Likewise.
	* sysdeps/ieee754/ldbl-opt/Versions (GLIBC_2.28): Add
	__nldbl_daddl.
	* sysdeps/ieee754/ldbl-opt/nldbl-compat.h (__nldbl_daddl): New
	prototype.
	* manual/arith.texi (Misc FP Arithmetic): Document fadd, faddl,
	daddl, fMaddfN, fMaddfNx, fMxaddfN and fMxaddfNx.
	* math/auto-libm-test-in: Add tests of add.
	* math/auto-libm-test-out-narrow-add: New generated file.
	* math/libm-test-narrow-add.inc: New file.
	* sysdeps/i386/fpu/s_f32xaddf64.c: Likewise.
	* sysdeps/ieee754/dbl-64/s_f32xaddf64.c: Likewise.
	* sysdeps/ieee754/dbl-64/s_fadd.c: Likewise.
	* sysdeps/ieee754/float128/s_f32addf128.c: Likewise.
	* sysdeps/ieee754/float128/s_f64addf128.c: Likewise.
	* sysdeps/ieee754/float128/s_f64xaddf128.c: Likewise.
	* sysdeps/ieee754/ldbl-128/s_daddl.c: Likewise.
	* sysdeps/ieee754/ldbl-128/s_f64xaddf128.c: Likewise.
	* sysdeps/ieee754/ldbl-128/s_faddl.c: Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_daddl.c: Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_faddl.c: Likewise.
	* sysdeps/ieee754/ldbl-96/s_daddl.c: Likewise.
	* sysdeps/ieee754/ldbl-96/s_faddl.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/nldbl-dadd.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/nldbl-fadd.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_daddl.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_fadd.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_faddl.c: Likewise.
	* sysdeps/powerpc/fpu/libm-test-ulps: Update.
	* sysdeps/mach/hurd/i386/libm.abilist: Likewise.
	* 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/riscv/rv64/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/tilegx32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
2018-02-10 02:08:43 +00:00
argp Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
assert Fix uninitialized variable in assert_perror (bug 22761) 2018-02-05 11:06:15 +01:00
benchtests benchtests: Make bench-memcmp print json 2018-02-02 09:56:47 +05:30
bits Post-cleanup 2: minimize _G_config.h. 2018-02-07 10:10:32 -05:00
catgets Update copyright dates not handled by scripts/update-copyrights. 2018-01-01 00:41:16 +00:00
ChangeLog.old Add missing reference to bug 21654 2017-10-07 13:14:36 +02:00
conform Don't install libio.h or _G_config.h. 2018-02-07 10:07:31 -05:00
crypt crypt: Fix badsalttest test (Bug 22765) 2018-02-01 00:02:49 -08:00
csu Post-cleanup 2: minimize _G_config.h. 2018-02-07 10:10:32 -05:00
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libio Post-cleanup 2: minimize _G_config.h. 2018-02-07 10:10:32 -05:00
locale Fix -Os strcoll, wcscoll, build (bug 21313). 2018-02-07 13:36:14 +00:00
localedata hr_HR: Add alternative month names (bug 10871). 2018-01-30 12:48:17 +01:00
login Update copyright dates not handled by scripts/update-copyrights. 2018-01-01 00:41:16 +00:00
mach hurd: Add expected ABI lists 2018-01-29 22:07:44 +01:00
malloc malloc: Use assert.h's assert macro 2018-01-29 23:00:17 +01:00
manual Add narrowing add functions. 2018-02-10 02:08:43 +00:00
math Add narrowing add functions. 2018-02-10 02:08:43 +00:00
mathvec Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
misc Fix -Os gnu_dev_* linknamespace, localplt issues (bug 15105, bug 19463). 2018-02-07 14:57:31 +00:00
nis libnsl: Turn remaining symbols into compat symbols [BZ #22701] 2018-01-29 17:42:30 +01:00
nptl Revert Intel CET changes to __jmp_buf_tag (Bug 22743) 2018-01-25 23:43:46 -08:00
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nscd hurd: Fix getifaddrs / freeifaddrs exposition 2018-01-28 19:06:15 +01:00
nss nss: Adjust tests to use nss_files only 2018-01-30 14:26:31 +01:00
po Update translations from the Translation Project 2018-01-17 22:00:50 +00:00
posix Define char16_t, char32_t consistently with uint_least16_t, uint_least32_t (bug 17979). 2018-02-07 20:33:55 +00:00
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soft-fp Do not use packed structures in soft-fp. 2018-02-01 20:44:49 +00:00
stdio-common Remove some unnecessary redefinitions of std symbols. 2018-02-05 19:58:01 -05:00
stdlib hurd: Fix build 2018-02-04 14:02:36 +01:00
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string Unify and simplify bits/byteswap.h, bits/byteswap-16.h headers (bug 14508, bug 15512, bug 17082, bug 20530). 2018-02-06 21:55:08 +00:00
sunrpc Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
support support: Preserve errno in write_message, TEST_VERIFY and other checks 2018-01-12 13:35:01 +01:00
sysdeps Add narrowing add functions. 2018-02-10 02:08:43 +00:00
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time time: Reference CLOCKS_PER_SEC in clock comment [BZ #22735] 2018-02-02 11:59:31 +01:00
timezone Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
wcsmbs Define char16_t, char32_t consistently with uint_least16_t, uint_least32_t (bug 17979). 2018-02-07 20:33:55 +00:00
wctype Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
.gitattributes Assume __NR_openat is always defined 2016-03-23 23:35:08 +01:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
abi-tags Remove the bulk of the NaCl port. 2017-05-20 08:09:10 -04:00
aclocal.m4 LIBC_SLIBDIR_RTLDDIR: substitute arguments in single quotes 2018-01-25 17:20:28 +01:00
ChangeLog Add narrowing add functions. 2018-02-10 02:08:43 +00:00
config.h.in Add RISC-V entries to config.h.in 2018-01-29 10:24:57 -08:00
config.make.in Pass -no-pie to GCC only if GCC defaults to PIE [BZ #22614] 2017-12-18 12:24:38 -08:00
configure Pass -no-pie to GCC only if GCC defaults to PIE [BZ #22614] 2017-12-18 12:24:38 -08:00
configure.ac Pass -no-pie to GCC only if GCC defaults to PIE [BZ #22614] 2017-12-18 12:24:38 -08:00
COPYING Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
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extra-lib.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
gen-locales.mk Split locale generation snippet into a separate file 2015-05-13 13:05:28 +05:30
INSTALL Fix typo in the previous commit 2018-01-31 23:13:00 +00:00
libc-abis A few more archs have IFUNC support. 2010-03-17 02:43:12 -07:00
libof-iterator.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
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Makefile.in New make target to only build benchmark binaries 2016-04-20 10:23:28 +05:30
Makerules Allow make-link-multidir to make subdirectories 2018-01-06 23:35:46 -08:00
NEWS Add narrowing add functions. 2018-02-10 02:08:43 +00:00
o-iterator.mk
README Skeleton documentation for the RISC-V port 2018-01-29 10:22:26 -08:00
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version.h Open master branch for glibc 2.28 development 2018-02-01 17:18:19 +00:00

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