C2X adds new <math.h> functions for floating-point maximum and
minimum, corresponding to the new operations that were added in IEEE
754-2019 because of concerns about the old operations not being
associative in the presence of signaling NaNs. fmaximum and fminimum
handle NaNs like most <math.h> functions (any NaN argument means the
result is a quiet NaN). fmaximum_num and fminimum_num handle both
quiet and signaling NaNs the way fmax and fmin handle quiet NaNs (if
one argument is a number and the other is a NaN, return the number),
but still raise "invalid" for a signaling NaN argument, making them
exceptions to the normal rule that a function with a floating-point
result raising "invalid" also returns a quiet NaN. fmaximum_mag,
fminimum_mag, fmaximum_mag_num and fminimum_mag_num are corresponding
functions returning the argument with greatest or least absolute
value. All these functions also treat +0 as greater than -0. There
are also corresponding <tgmath.h> type-generic macros.
Add these functions to glibc. The implementations use type-generic
templates based on those for fmax, fmin, fmaxmag and fminmag, and test
inputs are based on those for those functions with appropriate
adjustments to the expected results. The RISC-V maintainers might
wish to add optimized versions of fmaximum_num and fminimum_num (for
float and double), since RISC-V (F extension version 2.2 and later)
provides instructions corresponding to those functions - though it
might be at least as useful to add architecture-independent built-in
functions to GCC and teach the RISC-V back end to expand those
functions inline, which is what you generally want for functions that
can be implemented with a single instruction.
Tested for x86_64 and x86, and with build-many-glibcs.py.
powerpc-nofpu libc exports __sqrtsf2 and __sqrtdf2 symbols. The
export of these soft-fp symbols is a mistake; they aren't part of the
libgcc interface and GCC will never generate code that calls them.
This patch makes them into compat symbols (no code built for static
libc), moving their sources from the generic soft-fp sources to
sysdeps/powerpc/nofpu (the underlying soft-fp FP_SQRT functionality
remains of use to implement actual sqrt public interfaces, such as
sqrtl / sqrtf128 for which it is used on various platforms, but
__sqrt[sdt]f2 are not such interfaces).
Tested with build-many-glibcs.py for relevant platforms.
[BZ #18473]
* soft-fp/sqrttf2.c: Remove file.
* soft-fp/sqrtdf2.c: Move to ....
* sysdeps/powerpc/nofpu/sqrtdf2.c: ... here. Include
<shlib-compat.h>.
(__sqrtdf2): Make conditional on
[SHLIB_COMPAT (libc, GLIBC_2_3_2, GLIBC_2_28)]. Define as compat
symbol.
* soft-fp/sqrtsf2.c: Move to ....
* sysdeps/powerpc/nofpu/sqrtsf2.c: ... here. Include
<shlib-compat.h>.
(__sqrtsf2): Make conditional on
[SHLIB_COMPAT (libc, GLIBC_2_3_2, GLIBC_2_28)]. Define as compat
symbol.
* soft-fp/Makefile (gcc-single-routines): Remove sqrtsf2.
(gcc-double-routines): Remove sqrtdf2.
(gcc-quad-routines): Remove sqrttf2.
* sysdeps/nios2/Makefile [$(subdir) = soft-fp] (sysdep_routines):
Do not filter out sqrtsf2 and sqrtdf2.
* sysdeps/powerpc/nofpu/Makefile [$(subdir) = soft-fp]
(sysdep_routines): Add sqrtsf2 and sqrtdf2.
For soft-float powerpc, fmaxmagl and fminmagl generate spurious
"invalid" exceptions for quiet NaN arguments. This is another case of
the problems with fabsl inline expansion via comparisons, and so is
fixed by building those functions with -fno-builtin-fabsl.
Tested for powerpc (soft-float).
[BZ #22691]
* sysdeps/powerpc/nofpu/Makefile [$(subdir) = math]
(CFLAGS-s_fmaxmagl.c): New variable.
[$(subdir) = math] (CFLAGS-s_fminmagl.c: Likewise.
For soft-float powerpc, the remainderl function produces zero results
with the wrong sign for various inputs. This is another instance of
the problem with incorrect built-in fabsl expansion, so is fixed by
this patch using -fno-builtin-fabsl for this function.
Tested for powerpc (soft-float).
[BZ #22688]
* sysdeps/powerpc/nofpu/Makefile [$(subdir) = math]
(CFLAGS-e_remainderl.c): New variable.
For soft-float powerpc, various _Complex long double functions
generate spurious "invalid" exceptions, even with a compiler with GCC
bug 64811 fixed.
The problem is GCC's built-in fabsl expansion. Various files are
already built with -fno-builtin-fabsl because in this case (IBM long
double, for soft-float or e500v1) a fallback fabsl expansion based on
comparisons is used, which can produce the wrong sign of a zero
result. Those comparisons can also produce spurious exceptions for
NaN arguments. Furthermore, __builtin_fpclassify implemently uses
__builtin_fabsl, and is unaffected by -fno-builtin-fabsl, and the
fpclassify macro uses __builtin_fpclassify in the absence of
-fsignaling-nans. Thus, this patch arranges for the problem files
using fpclassify to be built with -fsignaling-nans in this case, to
avoid spurious exceptions from fpclassify.
Tested for powerpc (soft-float).
[BZ #22687]
* sysdeps/powerpc/nofpu/Makefile (CFLAGS-s_cacosl.c): New
variable.
(CFLAGS-s_cacoshl.c): Likewise.
(CFLAGS-s_casinhl.c): Likewise.
(CFLAGS-s_catanl.c): Likewise.
(CFLAGS-s_catanhl.c): Likewise.
(CFLAGS-s_cexpl.c): Likewise.
(CFLAGS-s_ccoshl.c): Add -fsignaling-nans.
(CFLAGS-s_csinhl.c): Likewise.
(CFLAGS-s_clogl.c): Likewise.
(CFLAGS-s_clog10l.c): Likewise.
(CFLAGS-s_csinl.c): Likewise.
(CFLAGS-s_csqrtl.c): Likewise.
A few math functions still use __fabs(f/l) rather than fabs, which
means they won't be inlined. Rename them so they are inlined.
Also add -fno-builtin-fabsl to nofpu powerpc makefile to work around
BZ #29253.
* sysdeps/ieee754/dbl-64/e_lgamma_r.c
(__ieee754_lgamma_r): Use fabs rather than __fabs.
* sysdeps/ieee754/dbl-64/e_log10.c (__ieee754_log10): Likewise.
* sysdeps/ieee754/dbl-64/e_log2.c (__ieee754_log2): Likewise.
* sysdeps/ieee754/flt-32/e_lgammaf_r.c
(__ieee754_lgammaf_r): Use fabsf rather than __fabsf.
* sysdeps/ieee754/flt-32/e_log10f.c (__ieee754_log10f): Likewise.
* sysdeps/ieee754/flt-32/e_log2f.c (__ieee754_log2f): Likewise.
* sysdeps/ieee754/ldbl-128/e_lgammal_r.c
(__ieee754_lgammal_r): Use fabsl rather than __fabsl.
* sysdeps/ieee754/ldbl-128/e_log10l.c (__ieee754_log10l): Likewise.
* sysdeps/ieee754/ldbl-128/e_log2l.c (__ieee754_log2l): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_lgammal_r.c
(__ieee754_lgammal_r): Use fabsl rather than __fabsl.
* sysdeps/ieee754/ldbl-128ibm/e_log10l.c (__ieee754_log10l): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_log2l.c (__ieee754_log2l): Likewise.
* sysdeps/powerpc/nofpu/Makefile: Add -fno-builtin-fabsl for BZ #29253.
This commit moves one step towards the deprecation of wrappers that
use _LIB_VERSION / matherr / __kernel_standard functionality, by
adding the suffix '_compat' to their filenames and adjusting Makefiles
and #includes accordingly.
New template wrappers that do not use such functionality will be added
by future patches and will be first used by the float128 wrappers.
This patch fixes bug 16390, incorrect signs of zero results from
ldbl-128ibm atan2l, soft-float only. The problem is a longstanding
GCC bug with fabsl not being correct for signed zero for soft float,
and the fix is using -fno-builtin-fabsl as a workaround, as already
done for various other source files. Tested powerpc-nofpu.
* sysdeps/powerpc/nofpu/Makefile [$(subdir) = math]
(CFLAGS-e_atan2l.c): Use -fno-builtin-fabsl.