TS 18661-1 defines libm functions that carry out an operation (+ - * /
sqrt fma) on their arguments and return a result rounded to a
(usually) narrower type, as if the original result were computed to
infinite precision and then rounded directly to the result type
without any intermediate rounding to the argument type. For example,
fadd, faddl and daddl for addition. These are the last remaining TS
18661-1 functions left to be added to glibc. TS 18661-3 extends this
to corresponding functions for _FloatN and _FloatNx types.
As functions parametrized by two rather than one varying
floating-point types, these functions require infrastructure in glibc
that was not required for previous libm functions. This patch
provides such infrastructure - excluding test support, and actual
function implementations, which will be in subsequent patches.
Declaring the functions uses a header bits/mathcalls-narrow.h, which
is included many times, for each relevant pair of types. This will
end up containing macro calls of the form
__MATHCALL_NARROW (__MATHCALL_NAME (add), __MATHCALL_REDIR_NAME (add), 2);
for each family of narrowing functions. (The structure of this macro
call, with the calls to __MATHCALL_NAME and __MATHCALL_REDIR_NAME
there rather than in the definition of __MATHCALL_NARROW, arises from
the names such as "add" *not* themselves being reserved identifiers -
meaning it's necessary to avoid any indirection that would result in a
user-defined "add" macro being expanded.) Whereas for existing
functions declaring long double functions is disabled if _LIBC in the
case where they alias double functions, to facilitate defining the
long double functions as aliases of the double ones, there is no such
logic for the narrowing functions in this patch. Rather, the files
defining such functions are expected to use #define to hide the
original declarations of the alias names, to avoid errors about
defining aliases with incompatible types.
math/Makefile support is added for building the functions (listed in
libm-narrow-fns, currently empty) for all relevant pairs of types. An
internal header math-narrow.h is added for macros shared between
multiple function implementations - currently a ROUND_TO_ODD macro to
facilitate writing functions using the round-to-odd implementation
approach, and alias macros to create all the required function
aliases. libc_feholdexcept_setroundf128 and libc_feupdateenv_testf128
are added for use when required (only for x86_64). float128_private.h
support is added for ldbl-128 narrowing functions to be used for
_Float128.
Certain things are specifically omitted from this patch and the
immediate followups. tgmath.h support is deferred; there remain
unresolved questions about how the type-generic macros for these
functions are supposed to work, especially in the case of arguments of
integer type. The math.h / bits/mathcalls-narrow.h logic, and the
logic for determining what functions / aliases to define, will need
some adjustments to support the sqrt and fma functions, where
e.g. f32xsqrtf64 can just be an alias for sqrt rather than a separate
function. TS 18661-1 defines FP_FAST_* macros but no support is
included for defining them (they won't in general be true without
architecture-specific optimized function versions).
For each of the function groups (add sub mul div sqrt fma) there are
always six functions present (e.g. fadd, faddl, daddl, f32addf64,
f32addf32x, f32xaddf64). When _Float64x and _Float128 are supported,
there are seven more (e.g. f32addf64x, f32addf128, f64addf64x,
f64addf128, f32xaddf64x, f32xaddf128, f64xaddf128). In addition, in
the ldbl-opt case there are function names such as __nldbl_daddl (an
alias for f32xaddf64, which is not a reserved name in TS 18661-1, only
in TS 18661-3), for calls to daddl to be mapped to in the
-mlong-double-64 case. (Calls to faddl just get mapped to fadd, and
for sqrt and fma there won't be __nldbl_* functions because dsqrtl and
dfmal can just be mapped to sqrt and fma with -mlong-double-64.)
While there are six or thirteen functions present in each group (plus
__nldbl_* names only as an ABI, not an API), not all are distinct;
they fall in various groups of aliases. There are two distinct
versions built if long double has the same format as double; four if
they have distinct formats but there is no _Float64x or _Float128
support; five if long double has binary128 format; seven when
_Float128 is distinct from long double.
Architecture-specific optimized versions are possible, but not
included in my patches. For example, IA64 generally supports
narrowing the result of most floating-point instructions; Power ISA
2.07 (POWER8) supports double values as arguments to float
instructions, with the results narrowed as expected; Power ISA 3
(POWER9) supports round-to-odd for float128 instructions, so meaning
that approach can be used without needing to set and restore the
rounding mode and test "inexact". I intend to leave any such
optimized versions to the architecture maintainers. Generally in such
cases it would also make sense for calls to these functions to be
expanded inline (given -fno-math-errno); I put a suggestion for TS
18661-1 built-in functions at <https://gcc.gnu.org/wiki/SummerOfCode>.
Tested for x86_64 (this patch in isolation, as well as testing for
various configurations in conjunction with further patches).
* math/bits/mathcalls-narrow.h: New file.
* include/bits/mathcalls-narrow.h: Likewise.
* math/math-narrow.h: Likewise.
* math/math.h (__MATHCALL_NARROW_ARGS_1): New macro.
(__MATHCALL_NARROW_ARGS_2): Likewise.
(__MATHCALL_NARROW_ARGS_3): Likewise.
(__MATHCALL_NARROW_NORMAL): Likewise.
(__MATHCALL_NARROW_REDIR): Likewise.
(__MATHCALL_NARROW): Likewise.
[__GLIBC_USE (IEC_60559_BFP_EXT)]: Repeatedly include
<bits/mathcalls-narrow.h> with _Mret_, _Marg_ and __MATHCALL_NAME
defined.
[__GLIBC_USE (IEC_60559_TYPES_EXT)]: Likewise.
* math/Makefile (headers): Add bits/mathcalls-narrow.h.
(libm-narrow-fns): New variable.
(libm-narrow-types-basic): Likewise.
(libm-narrow-types-ldouble-yes): Likewise.
(libm-narrow-types-float128-yes): Likewise.
(libm-narrow-types-float128-alias-yes): Likewise.
(libm-narrow-types): Likewise.
(libm-routines): Add narrowing functions.
* sysdeps/i386/fpu/fenv_private.h [__x86_64__]
(libc_feholdexcept_setroundf128): New macro.
[__x86_64__] (libc_feupdateenv_testf128): Likewise.
* sysdeps/ieee754/float128/float128_private.h: Include
<math/math-narrow.h>.
[libc_feholdexcept_setroundf128] (libc_feholdexcept_setroundl):
Undefine and redefine.
[libc_feupdateenv_testf128] (libc_feupdateenv_testl): Likewise.
(libm_alias_float_ldouble): Undefine and redefine.
(libm_alias_double_ldouble): Likewise.
The math/Makefile variable libm-test-incs was formerly used, but no
longer is. This patch removes it.
Tested for x86_64.
* math/Makefile [$(PERL) != no] (libm-test-incs): Remove variable.
Since GCC has support for accessing FPSR/FPCR, use them when possible
so that the asm instructions can be removed eventually. Although GCC 5
supports the builtins, it has an optimization bug, so use them from GCC 6
onwards.
* sysdeps/aarch64/fpu/fpu_control.h: Use builtins for accessing
FPCR/FPSR.
A number of cross-references to the GCC info manual cause Texinfo
warnings; e.g.:
./creature.texi:11: warning: @xref node name should not contain `.'
This is due to "gcc.info" being used in the INFO-FILE-NAME (fourth)
argument. Changing it to "gcc" removes these warnings. (Manually
confirmed equivalent behaviour for make info, html, and pdf.)
* manual/creature.texi: Convert references to gcc.info to gcc.
* manual/stdio.texi: Likewise.
* manual/string.texi: Likewise.
As noted in bug 17979 (and as I noted earlier in
<https://sourceware.org/ml/libc-alpha/2012-02/msg00647.html>), uchar.h
has gratuitously complicated code to determine the types for char16_t
and char32_t, and to reject including that header for pre-C11
compilers not defining __CHAR16_TYPE__ and __CHAR32_TYPE__. Since
those types are always required to match uint_least16_t and
uint_least32_t, which glibc knows how to define without reference to
such predefined macros, it's safe just to define those types the same
as the *least* types are defined in stdint.h, so allowing the header
to work with (for example) GCC 4.3.
This patch implements that. bits/types.h is made to define
__int_leastN_t and __uint_leastN_t so the logic for those types can
stay in a single place, and stdint.h is made to use those __*_t to
define the public *_t types. uchar.h is then made to use
__uint_least16_t and __uint_least32_t to define char16_t and char32_t,
so simplifying the logic there. A new test is added that verifies the
types chosen for char16_t and char32_t do indeed match the types the
compiler uses for u"" and U"" string literals.
Tested for x86_64. (I have not tested with any of the older compilers
for which this would actually make a difference to whether you can
include uchar.h.)
[BZ #17979]
* posix/bits/types.h (__int_least8_t): New typedef.
(__uint_least8_t): Likewise.
(__int_least16_t): Likewise.
(__uint_least16_t): Likewise.
(__int_least32_t): Likewise.
(__uint_least32_t): Likewise.
(__int_least64_t): Likewise.
(__uint_least64_t): Likewise.
* sysdeps/generic/stdint.h (int_least8_t): Define using
__int_least8_t.
(int_least16_t): Define using __int_least16_t.
(int_least32_t): Define using __int_least32_t.
(int_least64_t): Define using __int_least64_t.
(uint_least8_t): Define using __uint_least8_t.
(uint_least16_t): Define using __uint_least16_t.
(uint_least32_t): Define using __uint_least32_t.
(uint_least64_t): Define using __uint_least64_t.
* wcsmbs/uchar.h: Include <bits/types.h>.
(char16_t): Define using __uint_least16_t conditional only on
[!__USE_ISOCXX11].
(char32_t): Define using __uint_least32_t conditional only on
[!__USE_ISOCXX11].
* wcsmbs/test-char-types.c: New file.
* wcsmbs/Makefile (tests): Add test-char-types.
Nearly everything in _G_config.h is either junk or more appropriately
defined elsewhere:
* _G_fpos_t, _G_fpos64_t, and _G_BUFSIZ are already completely unused.
* All remaining uses of _G_va_list have been changed to __gnuc_va_list.
* The definition of _G_HAVE_ST_BLKSIZE/_IO_HAVE_ST_BLKSIZE has
been inlined into its sole use.
* The complete definition of _G_iconv_t has been moved to libio.h and
renamed _IO_iconv_t (all actual users used that name).
* _G_IO_IO_FILE_VERSION is vestigial; some code cares whether
_IO_stdin_used exists, but nothing looks at its value. I've
preserved the value as a hardwired constant in csu/init.c.
This means csu/init.c no longer needs to include anything.
* Many of the headers included by _G_config.h were already being
included directly by either either libio.h or stdio.h; the
remaining ones were moved to libio.h.
* _G_HAVE_MREMAP is still relevant, because mremap genuinely is a
Linux extension; it's not in POSIX and as far as I can tell it's
not available on the Hurd either. I also preserved _G_HAVE_MMAP,
since it's conceivable someone would want to port glibc to a
MMU-less, mmap-less environment in the future. Both are now always
defined to 1/0 as is the current convention, instead of the older
1/undef convention. These are the only symbols still defined in
_G_config.h.
* The actual inclusion of _G_config.h moves from libio.h to libioP.h,
as this is where a potential override of _G_HAVE_MMAP happens.
* The #ifdef logic in libioP.h controlling _IO_JUMPS_OFFSET has been
simplified.
After this patch, the only surviving _G_ symbols are the struct tag
names _G_fpos_t and _G_fpos64_t, which are preserved for the sake of
C++ mangled names in applications, and _G_HAVE_MMAP and _G_HAVE_MREMAP,
which do not seem worth renaming.
Installed stripped libraries are unchanged by this patch.
* bits/_G_config.h: Move back to sysdeps/generic/_G_config.h.
Delete all contents except for definitions of _G_HAVE_MMAP and
_G_HAVE_MREMAP. Add commentary explaining those two symbols.
* sysdeps/unix/sysv/linux/bits/_G_config.h: Move back to
sysdeps/unix/sysv/linux/_G_config.h. Make same content
change as above.
* libio/libio.h: Don't include bits/_G_config.h here.
Include stddef.h with __need_wchar_t defined. Include
bits/types/__mbstate_t.h, bits/types/wint_t.h, and gconv.h.
Define _IO_iconv_t here, directly.
Don't define _IO_HAVE_ST_BLKSIZE.
* libio/libioP.h: Include _G_config.h here. Move include of
shlib-compat.h up with rest of includes. Simplify conditionals
controlling definition of _IO_JUMPS_OFFSET.
* csu/init.c: Remove always-true #if around entire file.
Don't include stdio.h. Set _IO_stdin_used to hardwired
constant 0x20001, and update commentary.
* include/stdio.h, sysdeps/ieee754/ldbl-opt/nldbl-compat.h:
Replace all uses of _G_va_list with __gnuc_va_list.
* libio/filedoalloc.c: Use #if defined _STATBUF_ST_BLKSIZE
instead of #if _IO_HAVE_ST_BLKSIZE.
* libio/fileops.c: Test _G_HAVE_MREMAP with #if, not #ifdef.
* libio/iofdopen.c, libio/iofopen.c: Test _G_HAVE_MMAP with #if,
not #ifdef.
We can't go very far with libio cleanups as long as we still have
_IO_MTSAFE_IO, and I am not tackling that in this patch series,
but we can at least make the maze of stdio-related headers a
little less complicated.
In this patch, libio.h moves back out of bits/ into the top level of
the libio subdirectory, and is merged with libio/bits/libio-ldbl.h
(which also used to be installed) and include/libio.h. Since almost
no files include libio.h directly, this is quite straightforward.
libio.h is now always used with _LIBC defined, so all of the _LIBC ||
_GLIBCPP_USE_WCHAR_T conditionals are unnecessary. Similarly, the
ifdef nest surrounding the definition of _IO_fwide_maybe_incompatible
can collapse down to a single SHLIB_COMPAT check. I also took the
opportunity to add some checks for configuration botches to libio.h.
Installed stripped libraries are unchanged by this patch.
* libio/bits/libio.h: Move back to libio/libio.h and adjust
multiple-include guard to match.
Merge contents of libio/bits/libio-ldbl.h and include/libio.h
into this file.
Remove preprocessor conditionals that are always true and/or
redundant to other preprocessor conditionals in the same nest.
Include shlib-compat.h unconditionally.
Error out if _LIBC is not defined, or if _ISOMAC is defined,
or if _IO_MTSAFE_IO is defined but _IO_lock_t_defined is not
defined after including stdio.h.
Use __BEGIN_DECLS/__END_DECLS.
* libio/bits/libio-ldbl.h, include/bits/libio.h: Delete file.
* include/stdio.h, libio/iolibio.h, libio/libioP.h: Include
libio.h as <libio/libio.h> rather than as <bits/libio.h>.
We shipped 2.27 with libio.h and _G_config.h still installed but
issuing warnings when used. Let's stop installing them early in 2.28
so that we have plenty of time to think of another plan if there are
problems.
The public stdio.h had a genuine dependency on libio.h for the
complete definitions of FILE and cookie_io_functions_t, and a genuine
dependency on _G_config.h for the complete definitions of fpos_t and
fpos64_t; these are moved to single-type headers.
bits/types/struct_FILE.h also provides a handful of accessor and
bitflags macros so that code is not duplicated between bits/stdio.h
and libio.h. All the other _IO_ and _G_ names used by the public
stdio.h can be replaced with either public names or __-names.
In order to minimize the risk of breaking our own compatibility code,
bits/types/struct_FILE.h preserves the _IO_USE_OLD_IO_FILE mechanism
exactly as it was in libio.h, but you have to define _LIBC to use it,
or it'll error out. Similarly, _IO_lock_t_defined is preserved
exactly, but will error out if used without defining _LIBC.
Internally, include/stdio.h continues to include libio.h, and libio.h
scrupulously provides every _IO_* and _G_* name that it always did,
perhaps now defined in terms of the public names. This is how this
patch avoids touching dozens of files throughout glibc and becoming
entangled with the _IO_MTSAFE_IO mess. The remaining patches in this
series eliminate most of the _G_ names.
Tested on x86_64-linux; in addition to the test suite, I installed the
library in a sysroot and verified that a simple program that uses
stdio.h could be compiled against the installed library, and I also
verified that installed stripped libraries are unchanged.
* libio/bits/types/__fpos_t.h, libio/bits/types/__fpos64_t.h:
New single-type headers split from _G_config.h.
* libio/bits/types/cookie_io_functions_t.h
* libio/bits/types/struct_FILE.h
New single-type headers split from libio.h.
* libio/Makefile: Install the above new headers. Don't install
libio.h, _G_config.h, bits/libio.h, bits/_G_config.h, or
bits/libio-ldbl.h.
* libio/_G_config.h, libio/libio.h: Delete file.
* libio/bits/libio.h: Remove improper-inclusion guard.
Include stdio.h and don't repeat anything that it does.
Define _IO_fpos_t as __fpos_t, _IO_fpos64_t as __fpos64_t,
_IO_BUFSIZ as BUFSIZ, _IO_va_list as __gnuc_va_list,
__io_read_fn as cookie_read_function_t,
__io_write_fn as cookie_write_function_t,
__io_seek_fn as cookie_seek_function_t,
__io_close_fn as cookie_close_function_t,
and _IO_cookie_io_functions_t as cookie_io_functions_t.
Define _STDIO_USES_IOSTREAM, __HAVE_COLUMN, and _IO_file_flags
here, in the "compatibility defines" section. Remove an #if 0
block. Use the "body" macros from bits/types/struct_FILE.h to
define _IO_getc_unlocked, _IO_putc_unlocked, _IO_feof_unlocked,
and _IO_ferror_unlocked.
Move prototypes of __uflow and __overflow...
* libio/stdio.h: ...here. Don't include bits/libio.h.
Don't define _STDIO_USES_IOSTREAM. Get __gnuc_va_list
directly from stdarg.h. Include bits/types/__fpos_t.h,
bits/types/__fpos64_t.h, bits/types/struct_FILE.h,
and, when __USE_GNU, bits/types/cookie_io_functions_t.h.
Use __gnuc_va_list, not _G_va_list; __fpos_t, not _G_fpos_t;
__fpos64_t, not _G_fpos64_t; FILE, not struct _IO_FILE;
cookie_io_functions_t, not _IO_cookie_io_functions_t;
__ssize_t, not _IO_ssize_t. Unconditionally define
BUFSIZ as 8192 and EOF as (-1).
* libio/bits/stdio.h: Add multiple-include guard. Use the "body"
macros from bits/types/struct_FILE.h instead of _IO_* macros
from libio.h; use __gnuc_va_list instead of va_list and __ssize_t
instead of _IO_ssize_t.
* libio/bits/stdio2.h: Similarly.
* libio/iolibio.h: Add multiple-include guard.
Include bits/libio.h after stdio.h.
* libio/libioP.h: Add multiple-include guard.
Include stdio.h and bits/libio.h before iolibio.h.
* include/bits/types/__fpos_t.h, include/bits/types/__fpos64_t.h
* include/bits/types/cookie_io_functions_t.h
* include/bits/types/struct_FILE.h: New wrappers.
* bits/_G_config.h, sysdeps/unix/sysv/linux/_G_config.h:
Get definitions of _G_fpos_t and _G_fpos64_t from
bits/types/__fpos_t.h and bits/types/__fpos64_t.h
respectively. Remove improper-inclusion guards.
* conform/data/stdio.h-data: Update expectations of va_list.
* scripts/check-installed-headers.sh: Remove special case for
libio.h and _G_config.h.
Building with -Os produces linknamespace and localplt failures for,
among other functions, gnu_dev_major, gnu_dev_minor and
gnu_dev_makedev.
The issue is that those functions are not inlined when building with
-Os. While one could force them to be inlined in that case, it seems
more natural to fix this issue similarly to other namespace issues.
Thus, this patch makes gnu_dev_* into weak aliases for hidden symbols
__gnu_dev_*; __gnu_dev_* are then defined as inlines in the internal
include/sys/sysmacros.h, and uses of gnu_dev_* (often via the macros
major, minor and makedev) for which there are namespace issues are
changed to use __gnu_dev_*; where there are no namespace issues, use
of libc_hidden_proto serves to avoid unnecessary local PLT entry use.
Tested for x86_64, (a) without -Os, to verify the testsuite continues
to pass without problems and that the functions called under their new
names continue to be inlined as expected in that case; (b) with -Os,
to verify that the linknamespace and localplt failures in question go
away (but because of other such failures present, neither of the
relevant bugs can yet be closed).
[BZ #15105]
[BZ #19463]
* include/sys/sysmacros.h [!_ISOMAC]
(__SYSMACROS_NEED_IMPLEMENTATION): Define macro.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC]
(_SYS_SYSMACROS_H_WRAPPER): Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (gnu_dev_major): Use
libc_hidden_proto.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (gnu_dev_minor): Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (gnu_dev_makedev):
Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__SYSMACROS_DECL_TEMPL):
Undefine and redefine to add use __gnu_dev_ prefix.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__SYSMACROS_IMPL_TEMPL):
Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__gnu_dev_major): Declare
and define as hidden inline function.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__gnu_dev_minor):
Likewise.
[!_SYS_SYSMACROS_H_WRAPPER && !_ISOMAC] (__gnu_dev_makedev):
Likewise.
* misc/makedev.c (OUT_OF_LINE_IMPL_TEMPL): Use __gnu_dev_ prefix.
(gnu_dev_major): Use weak_alias and libc_hidden_weak.
(gnu_dev_minor): Likewise.
(gnu_dev_makedev): Likewise.
* csu/check_fds.c (check_one_fd): Use __gnu_dev_makedev instead of
makedev.
* posix/wordexp.c (exec_comm_child): Likewise.
* sysdeps/mach/hurd/xmknodat.c (__xmknodat): Use __gnu_dev_minor
instead of minor and __gnu_dev_major instead of major.
* sysdeps/unix/sysv/linux/device-nrs.h (DEV_TTY_P): Use
__gnu_dev_major instead of major.
* sysdeps/unix/sysv/linux/pathconf.c (distinguish_extX): Use
__gnu_dev_major instead of gnu_dev_major and __gnu_dev_minor
instead of gnu_dev_minor.
* sysdeps/unix/sysv/linux/ptsname.c (MASTER_P): Likewise.
(SLAVE_P): Likewise.
(__ptsname_internal): Use __gnu_dev_minor instead of minor.
* sysdeps/unix/sysv/linux/ttyname.h (is_pty): Use __gnu_dev_major
instead of major.
The findidx functions used in implementing strcoll / wcscoll already
use DIAG_IGNORE_Os_NEEDS_COMMENT for spurious -Wmaybe-uninitialized
warnings that appear with -Os. In building with GCC 7 for x86_64 with
-Os, I find there are additional such warnings, for the same structure
elements, which are spurious for the same reasons given in the
existing comments (and this was also reported for MIPS with GCC 5 in
bug 21313). This patch adds corresponding uses of DIAG_* in the
places that get the additional warnings.
Tested for x86_64 with -Os that this eliminates those warnings and so
allows the build to progress further.
[BZ #21313]
* locale/weight.h (findidx): Disable -Wmaybe-uninitialized for -Os
in another place.
* locale/weightwc.h (findidx): Likewise.
Remove the slow paths from log. Like several other double precision math
functions, log is exactly rounded. This is not required from math functions
and causes major overheads as it requires multiple fallbacks using higher
precision arithmetic if a result is close to 0.5ULP. Ridiculous slowdowns
of up to 100000x have been reported when the highest precision path triggers.
Interestingly removing the slow paths makes hardly any difference in practice:
the worst case error is still ~0.502ULP, and exp(log(x)) shows identical results
before/after on many millions of random cases. All GLIBC math tests pass on
AArch64 and x64 with no change in ULP error. A simple test over a few hundred
million values shows log is now 18% faster on average.
* manual/probes.texi (slowlog): Delete documentation of removed probe.
(slowlog_inexact): Likewise
* sysdeps/ieee754/dbl-64/e_log.c (__ieee754_log): Remove slow paths.
* sysdeps/ieee754/dbl-64/ulog.h: Remove unused declarations.
We have a general principle of preferring optimizations for library
facilities to use compiler built-in functions rather than being
located in library headers, where the compiler can reasonably optimize
code without needing to know glibc implementation details.
This patch applies this principle to bits/byteswap.h, eliminating all
the architecture-specific variants and bits/byteswap-16.h. The
__bswap_16, __bswap_32 and __bswap_64 interfaces all become inline
functions, never macros, using the GCC built-in functions where
available and otherwise a single architecture-independent definition
using shifts and masking (which compilers may well be able to detect
and optimize; GCC has detection of various byte-swapping idioms).
The __bswap_constant_32 macro needs to stay around because of uses in
static initializers within glibc and its tests, and so for consistency
all __bswap_constant_* are kept rather than just being inlined into
the old-GCC-or-non-GCC parts of the __bswap_* inline function
definitions.
Various open bugs are addressed by this cleanup, with caveats about
exactly what is covered by those bugs and when the bugs applied at
all.
Bug 14508 reports -Wformat warnings building glibc because __bswap_*
sometimes returned the wrong types. Obviously we already don't have
such warnings any more or the build would be failing, given -Werror,
and I suspect that bug was originally for wrong types for x86_64, as
fixed by commit d394eb742a (glibc 2.17).
The only case I saw removed by this patch where the types would still
have been wrong was the non-__GNUC__ case of __bswap_64 in the s390
header (using unsigned long long int, but uint64_t would be unsigned
long int for 64-bit). In any case, the single header consistently
uses __uintN_t types after this patch, thereby eliminating all such
bugs. The existing string/test-endian-types.c test already suffices
to verify that the types are correct with the compiler used to build
glibc and its tests.
Bug 15512 reports an error from __bswap_constant_16 with -Werror
-Wsign-conversion. I am unable to reproduce this with any GCC version
supporting -Wsign-conversion - all seem to be able to avoid warning
for ((x) >> 8) & 0xffu, where x is uint16_t, which while it formally
does involve an implicit conversion from int to unsigned int, is also
a case where it should be easy for the compiler to see that the value
converted is never negative. But in this patch __bswap_constant_16 is
changed to use signed 0xff so that no such implicit conversion occurs
at all, and a test with -Werror -Wsign-conversion is added.
Bug 17082 objects to the use of ({}) statement expressions in these
macros preventing use at file scope (in C, that's in sizeof etc.; in
C++, more generally in static initializers). The particular case of
these interfaces is fixed by this patch as it changes them to inline
functions, eliminating all uses of ({}) in bits/byteswap.h, and a
corresponding testcase is added. The bug tries to raise a more
general policy question about use of ({}) in macros in installed
headers, referring to "many other libc functions" (unspecified which
functions are being considered).
Since such policy questions belong on libc-alpha, and since there
*are* macros in installed headers which can't really avoid using ({})
(where they are type-generic, so can't use an inline function, but
need a temporary variable, and a few where the interface involves
returning memory from alloca so can't use an inline function either),
I propose to consider that bug fixed with this change. That is
without prejudice to any other new bugs anyone wishes to file *for
precisely defined sets of macros* requesting moving away from ({})
*where it is clearly possible for those interfaces*. Where ({}) can
be avoided, typically by use of an inline function, I think that's a
good idea - that inline functions are typically to be preferred to
({}) for header interfaces where such optimizations are useful but the
interface is suited to being defined using an inline function.
Bug 20530 requests use of __builtin_bswap16 when available (GCC 4.8
and later), which this patch implements.
Tested for x86_64, and with build-many-glibcs.py. Also did an x86_64
test with the __GNUC_PREREQ conditionals changed to "#if 0" to verify
the old-GCC/non-GCC case in the headers. (There are already existing
tests for correctness of results of these interfaces.)
[BZ #14508]
[BZ #15512]
[BZ #17082]
[BZ #20530]
* bits/byteswap.h: Update file comment. Do not include
<bits/byteswap-16.h>.
(__bswap_constant_16): Cast result to __uint16_t. Use signed 0xff
constant.
(__bswap_16): Define as inline function.
(__bswap_constant_32): Reformat definition.
(__bswap_32): Always define as inline function, not macro, using
__uint32_t. Use __builtin_bswap32 if [__GNUC_PREREQ (4, 3)],
otherwise __bswap_constant_32.
(__bswap_constant_64): Reformat definition. Do not use
__extension__ here.
(__bswap_64): Always define as inline function, not macro. Use
__extension__ on function definition. Use __builtin_bswap64 if
[__GNUC_PREREQ (4, 3)], otherwise __bswap_constant_64.
* string/test-endian-file-scope.c: New file.
* string/test-endian-sign-conversion.c: Likewise.
* string/Makefile (headers): Remove bits/byteswap-16.h.
(tests): Add test-endian-file-scope and
test-endian-sign-conversion.
(CFLAGS-test-endian-sign-conversion.c): New variable.
* bits/byteswap-16.h: Remove file.
* sysdeps/ia64/bits/byteswap-16.h: Likewise.
* sysdeps/ia64/bits/byteswap.h: Likewise.
* sysdeps/m68k/bits/byteswap.h: Likewise.
* sysdeps/s390/bits/byteswap-16.h: Likewise.
* sysdeps/s390/bits/byteswap.h: Likewise.
* sysdeps/tile/bits/byteswap.h: Likewise.
* sysdeps/x86/bits/byteswap-16.h: Likewise.
* sysdeps/x86/bits/byteswap.h: Likewise.
Bug 17721 reports that the non-__GNUC__ definitions of __inline and
__restrict are suboptimal, in that they are defined to empty when they
could be defined to inline and restrict for appropriate language
versions. This patch makes those fixes.
Tested for x86_64 (however, I have not done any testing with an actual
non-__GNUC__ compiler and it's likely such compilers may have other
problems with glibc headers).
[BZ #17721]
* misc/sys/cdefs.h [!__GNUC__ && (__cplusplus || (__STDC_VERSION__
&& __STDC_VERSION__ >= 199901L))] (__inline): Define to inline.
[!__GNUC_PREREQ (2,92) && __STDC_VERSION__ && __STDC_VERSION__ >=
199901L] (__restrict): Define to restrict.
Bug 19667 reports unchecked malloc calls in the test
string/testcopy.c. This patch makes that test use xmalloc and the
support/test-driver.c test framework.
Tested for x86_64.
[BZ #19667]
* string/testcopy.c: Include <support/support.h>. Do not include
<malloc.h>. Use <support/test-driver.c>.
(main): Rename to do_test. Make static. Use xmalloc instead of
malloc.
Bug 13575 reports that SSIZE_MAX is wrongly defined as LONG_MAX on
32-bit systems where ssize_t is defined as int (which is most 32-bit
systems supported by glibc).
This patch fixes the definition, using a conditional on
__WORDSIZE32_SIZE_ULONG to determine the appropriate type in the
32-bit case. Formally ssize_t need not be the signed type
corresponding to size_t, but as it is for all current glibc
configurations, there is no need for a new macro different from the
one used for defining SIZE_MAX. A testcase is added for both the type
and the value of SSIZE_MAX.
There is a relevant peculiarity in
sysdeps/unix/sysv/linux/s390/bits/typesizes.h:
/* Compatibility with g++ 2.95.x. */
/* size_t is unsigned long int on s390 -m31. */
This has the effect that for GCC 2 for s390, ssize_t does not match
__WORDSIZE32_SIZE_ULONG. I don't think such a conditional on the GCC
version makes sense - to have a well-defined ABI, the choices of
standard types should not depend on the GCC version. It's also the
case that upstream GCC 2.95 did not support s390, and glibc headers
don't in general try to support past development GCC versions - only
actual releases and current mainline development. But whether or not
that GCC 2 case should be removed (with or without a NEWS entry for
such a change), this patch does not result in any changes for s390;
the value is always still LONG_MAX in the s390 case because
__WORDSIZE32_SIZE_ULONG is always defined for 32-bit s390. I don't
think any such oddity in code only active for unofficial or unreleased
old compiler versions should block closing the present bug as fixed
once this patch is in.
Tested for x86_64 and x86, and with build-many-glibcs.py.
[BZ #13575]
* posix/bits/posix1_lim.h: Include <bits/wordsize.h>.
[!SSIZE_MAX && !(__WORDSIZE == 64 || __WORDSIZE32_SIZE_ULONG)]
(SSIZE_MAX): Define to INT_MAX.
* posix/test-ssize-max.c: New file.
* posix/Makefile (tests): Add test-ssize-max.
Bug 19668 reports an unchecked malloc call in the test
sysdeps/powerpc/fpu/tst-setcontext-fpscr.c. This patch makes that
test use xmalloc. It does not otherwise move this test to the
support/ infrastructure or support/test-driver.c; the test has various
uses of exit and _exit on error cases, and uses atexit, and while I
think those things would all still work in the context of
test-driver.c, it's not an immediately obvious conversion the way it
would be for many tests that don't use test-driver.c.
Tested for powerpc.
[BZ #19668]
* sysdeps/powerpc/fpu/tst-setcontext-fpscr.c: Include
<support/support.h>. Do not include <malloc.h>.
(query_auxv): Use xmalloc instead of malloc.
Bug 14553 reports that sys/types.h defines loff_t unconditionally,
despite it not being part of any supported standard. This is
permitted by the POSIX *_t reservation, but as a
quality-of-implementation issue it's still best not to define it
except for __USE_MISC. This patch conditions the definition
accordingly, updating a macro in sysdeps/unix/sysv/linux/sys/quota.h
to use __loff_t so it still works even if __USE_MISC is not defined.
codesearch.debian.net suggests there are quite a lot of loff_t uses
outside glibc, but it might well make sense to change all (few) uses
of loff_t or __loff_t inside glibc to use off64_t or __off64_t
instead, leaving only the definitions, treating this name as
obsolescent.
Tested for x86_64.
[BZ #14553]
* posix/sys/types.h (loff_t): Only define for [__USE_MISC].
* sysdeps/unix/sysv/linux/sys/quota.h (dqoff): Use __loff_t
instead of loff_t.
The getc and putc macros in the public stdio.h expand to call _IO_getc
and _IO_putc respectively. As _IO_getc, fgetc, and getc are all aliases
for the same function, and _IO_putc, fputc, and putc are also all aliases
for the same function, the macros are pointless. The C standard does
not require getc and putc to be macros, so let's just not have macros.
All four symbols are exported from libc.so at the same, ancient symbol
version, so there should be no risks for binary compatibility. Similarly,
the getchar and putchar inlines in bits/stdio.h forward to getc and putc
instead of their _IO_ aliases.
As a change from longstanding historical practice, this does seem
like it might break _something_, so there is a note in NEWS, which
is also a convenient place to advise people that if they thought getc
and putc had reduced per-character overhead they should consider using
getc_unlocked and putc_unlocked instead. (These are also not macros,
but when optimizing, they are inlines.)
* libio/stdio.h: Don't define getc or putc as macros.
* libio/bits/stdio.h (getchar, putchar): Use getc and putc,
not _IO_getc and _IO_putc.
Two files in stdio-common were unnecessarily redefining some standard
symbols as their _IO_ aliases.
* stdio-common/vfprintf.c: Don't redefine FILE, va_list, or BUFSIZ.
* stdio-common/tstgetln.c: Don't redefine ssize_t.
This patch adds the TCP_FASTOPEN_KEY and TCP_FASTOPEN_NO_COOKIE macros
from Linux 4.15 to sysdeps/gnu/netinet/tcp.h.
Tested for x86_64.
* sysdeps/gnu/netinet/tcp.h (TCP_FASTOPEN_KEY): New macro.
(TCP_FASTOPEN_NO_COOKIE): Likewise.
This patch adds the IPV6_FREEBIND macro from Linux 4.15 to
sysdeps/unix/sysv/linux/bits/in.h.
Tested for x86_64.
* sysdeps/unix/sysv/linux/bits/in.h (IPV6_FREEBIND): New macro.
Linux 4.15 adds NT_S390_RI_CB to linux/elf.h (and NT_ARM_SVE, which we
already have in glibc). This shows up that various other ELF note
values from linux/elf.h are missing from glibc's elf.h.
This patch adds the missing values that are relevant to glibc
architectures. As elf.h is a general description of the ELF format,
not necessarily limited to glibc configurations, there's an argument
for having the remaining NT_* values that Linux uses for non-glibc
architectures in glibc's elf.h as well, but this patch does not add
them.
Adding the NT_PRFPREG name is bug 14890. That bug also requests
making the NT_FPREGSET name obsolete. Given that elf.h is not just
for Linux but can describe ELF for other operating systems, I don't
think that a change of name in the Linux kernel is sufficient
justification for declaring the other name obsolete; there can be
multiple names for the same note value, even with incompatible
semantics, if those reflect variants of the ELF format in actual use.
For example, FreeBSD appears still to have the name NT_FPREGSET
<https://github.com/freebsd/freebsd/blob/master/sys/sys/elf_common.h>
(note: I haven't checked whether the FreeBSD kernel actually generates
such notes or whether this is actually an other-OS definition present
in FreeBSD's header).
[BZ #14890]
* elf/elf.h (NT_PRFPREG): New macro.
(NT_S390_VXRS_LOW): Likewise.
(NT_S390_VXRS_HIGH): Likewise.
(NT_S390_GS_CB): Likewise.
(NT_S390_GS_BC): Likewise.
(NT_S390_RI_CB): Likewise.
This patch adds the MAP_SYNC macro from Linux 4.15 to various
bits/mman.h headers. Note that this is *not* added to all
architectures: in Linux 4.15, this macro is only in
asm-generic/mman.h, and only some architectures' asm/mman.h include
the asm-generic file - the architectures not using the asm-generic
file will need their own values of MAP_SYNC allocated to support this
functionality (some of them also already have conflicting mmap flags
so the value there will have to be different from the generic
0x80000). Specifically, for glibc architectures, alpha hppa mips
powerpc sparc tile lack allocations of values for MAP_SYNC.
Tested for x86_64.
* sysdeps/unix/sysv/linux/aarch64/bits/mman.h [__USE_MISC]
(MAP_SYNC): New macro.
* sysdeps/unix/sysv/linux/arm/bits/mman.h [__USE_MISC] (MAP_SYNC):
Likewise.
* sysdeps/unix/sysv/linux/ia64/bits/mman.h [__USE_MISC]
(MAP_SYNC): Likewise.
* sysdeps/unix/sysv/linux/m68k/bits/mman.h [__USE_MISC]
(MAP_SYNC): Likewise.
* sysdeps/unix/sysv/linux/microblaze/bits/mman.h [__USE_MISC]
(MAP_SYNC): Likewise.
* sysdeps/unix/sysv/linux/nios2/bits/mman.h [__USE_MISC]
(MAP_SYNC): Likewise.
* sysdeps/unix/sysv/linux/riscv/bits/mman.h [__USE_MISC]
(MAP_SYNC): Likewise.
* sysdeps/unix/sysv/linux/s390/bits/mman.h [__USE_MISC]
(MAP_SYNC): Likewise.
* sysdeps/unix/sysv/linux/sh/bits/mman.h [__USE_MISC] (MAP_SYNC):
Likewise.
* sysdeps/unix/sysv/linux/x86/bits/mman.h [__USE_MISC] (MAP_SYNC):
Likewise.
This patch adds the MAP_SHARED_VALIDATE macro from Linux 4.15 to
bits/mman-linux.h and the hppa bits/mman.h.
Tested for x86_64.
* sysdeps/unix/sysv/linux/bits/mman-linux.h [__USE_MISC]
(MAP_SHARED_VALIDATE): New macro.
* sysdeps/unix/sysv/linux/hppa/bits/mman.h [__USE_MISC]
(MAP_SHARED_VALIDATE): Likewise.
The only differences in ld.so are line numbers for asserts.
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
* elf/dl-addr.c (determine_info): Use ADDRIDX with DT_GNU_HASH.
* elf/dl-lookup.c (_dl_setup_hash): Likewise.
* elf/get-dynamic-info.h (elf_get_dynamic_info): Likewise.
Since start.o may be compiled as PIC, we should check PIC instead of
SHARED.
[BZ #22638]
* sysdeps/sparc/sparc32/start.S (_start): Check PIC instead of
SHARED.
* sysdeps/sparc/sparc64/start.S (_start): Likewise.
Keeping the buffers the same across test runs gives later invocations
the advantage since they access cached data. Reallocate so that all
test runs are on equal grounds.
* benchtests/bench-memcmp.c (do_test): Call realloc_buf for
every test run.
This patch updates sysdeps/unix/sysv/linux/syscall-names.list for
Linux 4.15. There only appears to be one new syscall to add to the
list. (The riscv_flush_icache syscall is *not* added because for
whatever reason it doesn't appear in the uapi asm/unistd.h; only in
arch/riscv/include/uapi/asm/syscalls.h, which is only included by the
non-uapi asm/unistd.h - and only syscalls whose __NR_* macros are
defined in the uapi asm/unistd.h are relevant for this list.)
Tested for x86_64, and with build-many-glibcs.py.
* sysdeps/unix/sysv/linux/syscall-names.list: Update kernel
version to 4.15.
(s390_sthyi): New syscall.
The general rule in glibc is that it's better for a macro to be always
defined, and tested with #if, than for it to be tested with #ifdef,
because the latter is prone to typos in the macro name as well as to
the header with the macro accidentally not being included in a file
testing it. (Testing with an "if" statement is even better, in those
cases where it's possible to do things that way, as it then means both
cases in the code get checked for syntax in glibc builds with either
value of the condition.)
math_private.h has several different groups of macros, meaning that
architectures wanting to override some of them need to define those
then include the generic version, which then defines macros if not
already defined. It's hard to avoid that arrangement completely, but
various cases can be improved by splitting out macros or groups of
macros into separate files.
This patch splits out the LDBL_CLASSIFY_COMPAT macro into a separate
ldbl-classify-compat.h header. This macro is tested with #ifdef; this
patch changes it to testing with #if, with a default definition to 0
in the generic header and then architecture-specific headers defining
it to 1.
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by the patch.
* sysdeps/generic/ldbl-classify-compat.h: New file.
* sysdeps/arm/ldbl-classify-compat.h: Likewise.
* sysdeps/m68k/coldfire/ldbl-classify-compat.h: Likewise.
* sysdeps/microblaze/ldbl-classify-compat.h: Likewise.
* sysdeps/mips/ldbl-classify-compat.h: Likewise.
* sysdeps/nios2/ldbl-classify-compat.h: Likewise.
* sysdeps/sh/ldbl-classify-compat.h: Likewise.
* sysdeps/ieee754/dbl-64/s_finite.c: Include
<ldbl-classify-compat.h>.
[LDBL_CLASSIFY_COMPAT]: Test value, not whether defined.
* sysdeps/ieee754/dbl-64/s_isinf.c: Include
<ldbl-classify-compat.h>.
[LDBL_CLASSIFY_COMPAT]: Test value, not whether defined.
* sysdeps/ieee754/dbl-64/s_isnan.c: Include
<ldbl-classify-compat.h>.
[LDBL_CLASSIFY_COMPAT]: Test value, not whether defined.
* sysdeps/ieee754/dbl-64/wordsize-64/s_finite.c: Include
<ldbl-classify-compat.h>.
[LDBL_CLASSIFY_COMPAT]: Test value, not whether defined.
* sysdeps/ieee754/dbl-64/wordsize-64/s_isinf.c: Include
<ldbl-classify-compat.h>.
[LDBL_CLASSIFY_COMPAT]: Test value, not whether defined.
* sysdeps/ieee754/dbl-64/wordsize-64/s_isnan.c: Include
<ldbl-classify-compat.h>.
[LDBL_CLASSIFY_COMPAT]: Test value, not whether defined.
* sysdeps/arm/math_private.h (LDBL_CLASSIFY_COMPAT): Remove macro.
* sysdeps/mips/math_private.h (LDBL_CLASSIFY_COMPAT): Likewise.
* sysdeps/m68k/coldfire/math_private.h: Remove file.
* sysdeps/microblaze/math_private.h: Likewise.
* sysdeps/nios2/math_private.h: Likewise.
* sysdeps/sh/math_private.h: Likewise.
math_private.h headers for configurations lacking support for
floating-point exceptions and rounding modes define
libc_feholdexcept_setround to override the default version with one
that discards its rounding mode argument.
Unlike other such libc_fe* macros that I removed, this one is actually
used for such configurations (in dbl-64/e_sqrt.c). However, this does
not make the macro required. It's only used for such configurations
with FE_TONEAREST as the rounding mode (anything needing another mode
should not be used when that mode is unavailable), and the default
definition just calls __feholdexcept and __fesetround. Since we now
have suitable inline do-nothing definitions of __feholdexcept and
__fesetround for the cases of no exceptions and rounding modes, we can
just rely on those inlines to achieve the same optimization as this
macro definition. Thus, this patch removes those macro definitions
(and the math_private.h headers containing them, when no longer needed
after that removal).
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by the patch.
* sysdeps/m68k/coldfire/fpu/math_private.h: Move to ....
* sysdeps/m68k/coldfire/math_private.h: ... here.
* sysdeps/m68k/coldfire/nofpu/math_private.h: Remove file.
* sysdeps/tile/math_private.h: Likewise.
* sysdeps/microblaze/math_private.h (libc_feholdexcept_setround):
Remove macro.
* sysdeps/nios2/math_private.h (libc_feholdexcept_setround):
Likewise.
math_private.h headers for configurations lacking support for
floating-point exceptions and rounding modes define various libc_fe*
macros to override the default versions with ones that discard any
exception or rounding mode arguments.
Three of the four macros defined in these headers are no longer needed
there: those macros are only used in fma implementations that are not
used for such configurations, now all those configurations properly
use soft-fp fma implementations instead. (Effectively, those macros
were a workaround to allow glibc to build in the absence of a proper
fma implementation for this case - now there is such an
implementation, there is no need to support building the wrong
implementation for those configurations.) Thus, this patch removes
the unnecessary macros.
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by the patch.
* sysdeps/m68k/coldfire/nofpu/math_private.h (libc_fesetround):
Remove macro.
(libc_fetestexcept): Likewise.
(libc_feupdateenv_test): Likewise.
* sysdeps/microblaze/math_private.h (libc_fesetround): Likewise.
(libc_fetestexcept): Likewise.
(libc_feupdateenv_test): Likewise.
* sysdeps/nios2/math_private.h (libc_fesetround): Likewise.
(libc_fetestexcept): Likewise.
(libc_feupdateenv_test): Likewise.
* sysdeps/tile/math_private.h (libc_fesetround): Likewise.
(libc_fetestexcept): Likewise.
(libc_feupdateenv_test): Likewise.
Continuing the process of improving and cleaning up the handling of
configurations lacking support for floating-point exceptions and
rounding modes, this patch adds trivial inline definitions of
feholdexcept and __feholdexcept to the set of inlines for such
configurations in math_private.h. These inlines were missing from the
tile version used as a basis for the previous inlines, despite a few
such function calls ending up in libm.so.
Tested with build-many-glibcs.py. As expected, installed stripped
shared libraries are unchanged for architectures supporting exceptions
and rounding modes, but changed for architectures lacking such
support.
* sysdeps/generic/math_private.h
[!FE_HAVE_ROUNDING_MODES && FE_ALL_EXCEPT == 0] (feholdexcept):
New inline function.
[!FE_HAVE_ROUNDING_MODES && FE_ALL_EXCEPT == 0] (__feholdexcept):
Likewise.
The tile version of math_private.h defines some inline functions for
fenv.h functions, to optimize away internal calls to these functions
that do nothing given no support for floating-point exceptions and
rounding modes. (Some functions may have error cases for invalid
arguments, but those aren't applicable to the internal calls from
within glibc.) Other configurations lacking support for exceptions
and rounding modes lack such inline functions. This patch moves them
to the generic math_private.h, appropriately conditioned, so that all
such configurations can benefit from the.
include/fenv.h is made to check whether there are any non-default
rounding modes; that needs to be done there, rather than later,
because get-rounding-mode.h defines values for otherwise unsupported
FE_* rounding modes. It also gives an error for FE_TONEAREST
undefined, a case that already did not work for building the glibc
testsuite; the convention has by now been established that all
architectures need to provide a version of bits/fenv.h that at least
defines FE_TONEAREST.
Tested with build-many-glibcs.py. As expected, installed stripped
shared libraries are unchanged for tile and for architectures
supporting exceptions and rounding modes, but changed for non-tile
architectures not supporting exceptions and rounding modes that
previously lacked this optimization (e.g. Nios II libm.so is about 1kB
smaller).
The optimization is not in fact complete (does not cover feholdexcept
/ __feholdexcept, so a few calls to those remain unnecessarily within
libm even after this patch), but that can be dealt with separately.
* include/fenv.h [!_ISOMAC && !FE_TONEAREST]: Give #error.
[!_ISOMAC] (FE_HAVE_ROUNDING_MODES): New macro.
* sysdeps/generic/math_private.h
[!FE_HAVE_ROUNDING_MODES && FE_ALL_EXCEPT == 0] (fegetenv): New
inline function.
[!FE_HAVE_ROUNDING_MODES && FE_ALL_EXCEPT == 0] (__fegetenv):
Likewise.
[!FE_HAVE_ROUNDING_MODES && FE_ALL_EXCEPT == 0] (fesetenv):
Likewise.
[!FE_HAVE_ROUNDING_MODES && FE_ALL_EXCEPT == 0] (__fesetenv):
Likewise.
[!FE_HAVE_ROUNDING_MODES && FE_ALL_EXCEPT == 0] (feupdateenv):
Likewise.
[!FE_HAVE_ROUNDING_MODES && FE_ALL_EXCEPT == 0] (__feupdateenv):
Likewise.
[!FE_HAVE_ROUNDING_MODES] (fegetround): Likewise.
[!FE_HAVE_ROUNDING_MODES] (__fegetround): Likewise.
[!FE_HAVE_ROUNDING_MODES] (fesetround): Likewise.
[!FE_HAVE_ROUNDING_MODES] (__fesetround): Likewise.
* sysdeps/tile/math_private.h (fegetenv): Remove inline function.
(__fegetenv): Likewise.
(fesetenv): Likewise.
(__fesetenv): Likewise.
(feupdateenv): Likewise.
(__feupdateenv): Likewise.
(fegetround): Likewise.
(__fegetround): Likewise.
(fesetround): Likewise.
(__fesetround): Likewise.
Various configurations lacking support for floating-point exceptions
and rounding modes have a math_private.h that overrides certain
functions and macros, internal and external, to avoid references to
FE_* constants that are undefined in those configurations. For
example, there are unconditional feraiseexcept (FE_INVALID) calls in
generic libm code, and these macro definitions duly define
feraiseexcept to ignore its argument to avoid an error from FE_INVALID
being undefined.
In fact it is easy to tell in an architecture-independent way whether
this is needed, by testing whether FE_ALL_EXCEPT == 0. Thus, this
patch puts such a test, and feraiseexcept and __feraiseexcept macros,
in the generic math_private.h, so reducing the duplication between
architecture versions of this header. The feclearexcept macro present
in several versions of this header, and fetestexcept in the tile
version, are not needed; they would have been needed before there were
proper soft-fp fma implementations (when generic versions, that depend
on FE_TOWARDZERO and FE_INEXACT, were being used for configurations
not supporting those features), but aren't needed any more, and so are
removed.
The tile version of this header has several inline functions for
fenv.h functions to optimize calls to them away in such configurations
where they do nothing useful, and all these header versions also have
definitions of some of the libc_fe* internal macros. I intend to make
those generic in subsequent patches.
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by this patch.
* sysdeps/generic/math_private.h [FE_ALL_EXCEPT == 0]
(feraiseexcept): New macro.
[FE_ALL_EXCEPT == 0] (__feraiseexcept): Likewise.
* sysdeps/m68k/coldfire/nofpu/math_private.h (feraiseexcept):
Remove macro.
(__feraiseexcept): Likewise.
(feclearexcept): Likewise.
* sysdeps/microblaze/math_private.h (feraiseexcept): Likewise.
(__feraiseexcept): Likewise.
(feclearexcept): Likewise.
* sysdeps/nios2/math_private.h (feraiseexcept): Likewise.
(__feraiseexcept): Likewise.
(feclearexcept): Likewise.
* sysdeps/tile/math_private.h (feraiseexcept): Likewise.
(__feraiseexcept): Likewise.
(feclearexcept): Likewise.
(fetestexcept): Likewise.
Since I've been fixing build issues for ColdFire, this patch adds a
math-tests.h file for ColdFire, reflecting the lack of support for
exceptions and rounding modes for soft float. I think it is logically
correct, but have not tested it beyond build-many-glibcs.py for both
hard and soft float.
* sysdeps/m68k/coldfire/math-tests.h: New file.
