glibc/manual
Joseph Myers ec94343f59 Add femode_t functions.
TS 18661-1 defines a type femode_t to represent the set of dynamic
floating-point control modes (such as the rounding mode and trap
enablement modes), and functions fegetmode and fesetmode to manipulate
those modes (without affecting other state such as the raised
exception flags) and a corresponding macro FE_DFL_MODE.

This patch series implements those interfaces for glibc.  This first
patch adds the architecture-independent pieces, the x86 and x86_64
implementations, and the <bits/fenv.h> and ABI baseline updates for
all architectures so glibc keeps building and passing the ABI tests on
all architectures.  Subsequent patches add the fegetmode and fesetmode
implementations for other architectures.

femode_t is generally an integer type - the same type as fenv_t, or as
the single element of fenv_t where fenv_t is a structure containing a
single integer (or the single relevant element, where it has elements
for both status and control registers) - except where architecture
properties or consistency with the fenv_t implementation indicate
otherwise.  FE_DFL_MODE follows FE_DFL_ENV in whether it's a magic
pointer value (-1 cast to const femode_t *), a value that can be
distinguished from valid pointers by its high bits but otherwise
contains a representation of the desired register contents, or a
pointer to a constant variable (the powerpc case; __fe_dfl_mode is
added as an exported constant object, an alias to __fe_dfl_env).

Note that where architectures (that share a register between control
and status bits) gain definitions of new floating-point control or
status bits in future, the implementations of fesetmode for those
architectures may need updating (depending on whether the new bits are
control or status bits and what the implementation does with
previously unknown bits), just like existing implementations of
<fenv.h> functions that take care not to touch reserved bits may need
updating when the set of reserved bits changes.  (As any new bits are
outside the scope of ISO C, that's just a quality-of-implementation
issue for supporting them, not a conformance issue.)

As with fenv_t, femode_t should properly include any software DFP
rounding mode (and for both fenv_t and femode_t I'd consider that
fragment of DFP support appropriate for inclusion in glibc even in the
absence of the rest of libdfp; hardware DFP rounding modes should
already be included if the definitions of which bits are status /
control bits are correct).

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).  Other architecture versions are untested.

	* math/fegetmode.c: New file.
	* math/fesetmode.c: Likewise.
	* sysdeps/i386/fpu/fegetmode.c: Likewise.
	* sysdeps/i386/fpu/fesetmode.c: Likewise.
	* sysdeps/x86_64/fpu/fegetmode.c: Likewise.
	* sysdeps/x86_64/fpu/fesetmode.c: Likewise.
	* math/fenv.h: Update comment on inclusion of <bits/fenv.h>.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (fegetmode): New function
	declaration.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (fesetmode): Likewise.
	* bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (femode_t): New
	typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/aarch64/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/alpha/fpu/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/arm/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/hppa/fpu/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/ia64/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/m68k/fpu/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/microblaze/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/mips/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/nios2/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/powerpc/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (__fe_dfl_mode): New variable
	declaration.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/s390/fpu/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/sh/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/sparc/fpu/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/tile/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* sysdeps/x86/fpu/bits/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
	(femode_t): New typedef.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FE_DFL_MODE): New macro.
	* manual/arith.texi (FE_DFL_MODE): Document macro.
	(fegetmode): Document function.
	(fesetmode): Likewise.
	* math/Versions (fegetmode): New libm symbol at version
	GLIBC_2.25.
	(fesetmode): Likewise.
	* math/Makefile (libm-support): Add fegetmode and fesetmode.
	(tests): Add test-femode and test-femode-traps.
	* math/test-femode-traps.c: New file.
	* math/test-femode.c: Likewise.
	* sysdeps/powerpc/fpu/fenv_const.c (__fe_dfl_mode): Declare as
	alias for __fe_dfl_env.
	* sysdeps/powerpc/nofpu/fenv_const.c (__fe_dfl_mode): Likewise.
	* sysdeps/powerpc/powerpc32/e500/nofpu/fenv_const.c
	(__fe_dfl_mode): Likewise.
	* sysdeps/powerpc/Versions (__fe_dfl_mode): New libm symbol at
	version GLIBC_2.25.
	* 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.
2016-09-07 16:40:09 +00:00
..
examples glob: Simplify the interface for the GLOB_ALTDIRFUNC callback gl_readdir 2016-04-29 09:35:30 +02:00
argp.texi manual/argp.texi (Specifying Argp Parsers): Fix typo. 2015-10-14 11:49:58 -04:00
arith.texi Add femode_t functions. 2016-09-07 16:40:09 +00:00
charset.texi manual: fix typos in character set handling 2016-06-16 00:45:37 -04:00
check-safety.sh Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00
conf.texi * manual/conf.texi: Document MTASC-safety properties. 2014-01-29 05:26:47 -02:00
contrib.texi manual: fix spelling typos 2016-06-16 00:59:57 -04:00
creature.texi Support __STDC_WANT_IEC_60559_FUNCS_EXT__ feature test macro. 2016-08-03 22:21:37 +00:00
crypt.texi manual: fix spelling typos 2016-06-16 00:59:57 -04:00
ctype.texi manual: fix typos in the character handling chapter 2016-06-16 00:37:44 -04:00
debug.texi * manual/debug.texi: Document MTASC-safety properties. 2014-01-30 18:50:57 -02:00
dir
errno.texi manual: fix typos in error reporting 2016-05-19 23:25:06 -04:00
fdl-1.3.texi
filesys.texi manual: fix spelling typos 2016-06-16 00:59:57 -04:00
freemanuals.texi
getopt.texi * manual/getopt.texi: Document MTASC-safety properties. 2014-01-31 23:16:56 -02:00
header.texi
install-plain.texi BZ #15941: Fix INSTALL file regeneration failure with makeinfo 5.x 2013-12-05 09:58:20 +05:30
install.texi 2016-06-05 Paul Pluzhnikov <ppluzhnikov@google.com> 2016-06-05 08:41:13 -07:00
intro.texi manual: fix typo in the introduction 2016-05-19 23:22:59 -04:00
io.texi
ipc.texi manual/ipc.texi: Fix AC-safety notes. 2014-04-08 17:12:15 -04:00
job.texi ctermid: return string literal, document MT-Safety pitfall 2014-11-21 02:16:02 -02:00
lang.texi Split large string section; add truncation advice 2015-12-10 08:29:30 -08:00
lgpl-2.1.texi
libc-texinfo.sh Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00
libc.texinfo Fix doc quoting problems with Texinfo 5 2016-01-10 00:20:51 -08:00
libcbook.texi
libdl.texi * manual/libdl.texi: New. 2014-01-31 23:23:59 -02:00
libm-err-tab.pl Add nextup and nextdown math functions 2016-06-16 21:37:45 +05:30
llio.texi Fix exponents in manual. 2015-08-20 09:43:50 +02:00
locale.texi manual: fix spelling typos 2016-06-16 00:59:57 -04:00
macros.texi Fix exponents in manual. 2015-08-20 09:43:50 +02:00
maint.texi Fix two spaces after sentence. 2014-02-26 23:27:38 +01:00
Makefile Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
math.texi Support __STDC_WANT_IEC_60559_FUNCS_EXT__ feature test macro. 2016-08-03 22:21:37 +00:00
memory.texi manual: fix typos in the memory chapter 2016-06-16 00:33:53 -04:00
message.texi manual: fix typos in the message chapter 2016-06-16 01:14:32 -04:00
nss.texi manual: fix spelling typos 2016-06-16 00:59:57 -04:00
nsswitch.texi
pattern.texi manual: fix typos in the pattern chapter 2016-06-16 01:34:38 -04:00
pipe.texi * manual/pipe.texi: Document MTASC-safety properties. 2014-01-31 23:37:28 -02:00
platform.texi PowerPC: Extend Program Priority Register support 2015-08-19 17:43:26 -03:00
probes.texi Fix two spaces after sentence. 2014-02-26 23:27:38 +01:00
process.texi Remove union wait [BZ #19613] 2016-04-14 08:54:57 +02:00
resource.texi Fix typo in manual. 2014-06-05 01:13:04 +02:00
search.texi manual: fix typos in the search chapter 2016-06-16 01:24:16 -04:00
setjmp.texi manual/setjmp.texi: Clarify setcontext and signal handlers text 2014-04-17 11:40:36 +01:00
signal.texi Fix crossreference to nonexistent node BSD Handler 2014-11-18 11:19:20 +01:00
socket.texi Fix two spaces after sentence. 2014-02-26 23:27:38 +01:00
startup.texi Remove _BSD_SOURCE and _SVID_SOURCE. 2014-02-11 23:40:07 +00:00
stdio-fp.c
stdio.texi Split large string section; add truncation advice 2015-12-10 08:29:30 -08:00
string.texi manual: fix spelling typos 2016-06-16 00:59:57 -04:00
summary.awk Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
sysinfo.texi Make obsolete syscall wrappers into compat symbols (bug 18472). 2015-12-14 22:52:15 +00:00
syslog.texi * manual/syslog.texi: Document MTASC-safety properties. 2014-02-01 01:22:09 -02:00
terminal.texi * manual/terminal.texi: Document MTASC-safety properties. 2014-02-01 03:53:15 -02:00
texinfo.tex Update miscellaneous files from upstream sources. 2016-01-05 18:04:06 +00:00
texis.awk
threads.texi Remove CPU set size checking from affinity functions [BZ #19143] 2015-11-24 17:21:01 +01:00
time.texi * manual/time.texi (TZ Variable): glibc no longer comes with tzdata. 2015-02-16 15:32:34 -08:00
tsort.awk Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00
users.texi manual: cuserid is mtasurace if not passed a string 2014-11-21 02:15:09 -02:00
xtract-typefun.awk Make shebang interpreter directives consistent 2016-01-07 04:03:21 -05:00