Continuing the preparation for additional _FloatN / _FloatNx function
aliases, this patch makes i386 libm function implementations use
libm_alias_float (or libm_alias_float_other in cases where the main
symbol name is defined with versioned_symbol) to define function
aliases.
Tested with build-many-glibcs.py for all its i386 configurations that
installed stripped shared libraries are unchanged by the patch, as
well as running the full glibc testsuite for i686.
* sysdeps/i386/fpu/s_asinhf.S: Include <libm-alias-float.h>.
(asinhf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_atanf.S: Include <libm-alias-float.h>.
(atanf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_cbrtf.S: Include <libm-alias-float.h>.
(cbrtf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_ceilf.S: Include <libm-alias-float.h>.
(ceilf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_copysignf.S: Include <libm-alias-float.h>.
(copysignf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_expm1f.S: Include <libm-alias-float.h>.
(expm1f): Define using libm_alias_float.
* sysdeps/i386/fpu/s_fabsf.S: Include <libm-alias-float.h>.
(fabsf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_floorf.S: Include <libm-alias-float.h>.
(floorf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_fmaxf.S: Include <libm-alias-float.h>.
(fmaxf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_fminf.S: Include <libm-alias-float.h>.
(fminf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_frexpf.S: Include <libm-alias-float.h>.
(frexpf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_llrintf.S: Include <libm-alias-float.h>.
(llrintf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_logbf.S: Include <libm-alias-float.h>.
(logbf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_lrintf.S: Include <libm-alias-float.h>.
(lrintf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_nearbyintf.S: Include <libm-alias-float.h>.
(nearbyintf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_remquof.S: Include <libm-alias-float.h>.
(remquof): Define using libm_alias_float.
* sysdeps/i386/fpu/s_rintf.S: Include <libm-alias-float.h>.
(rintf): Define using libm_alias_float.
* sysdeps/i386/fpu/s_truncf.S: Include <libm-alias-float.h>.
(truncf): Define using libm_alias_float.
* sysdeps/i386/i686/fpu/multiarch/e_exp2f.c: Include
<libm-alias-float.h>.
(exp2f): Define using libm_alias_float, or libm_alias_float_other
if [SHARED].
* sysdeps/i386/i686/fpu/multiarch/e_expf.c: Include
<libm-alias-float.h>.
(expf): Define using libm_alias_float, or libm_alias_float_other
if [SHARED].
* sysdeps/i386/i686/fpu/multiarch/e_log2f.c: Include
<libm-alias-float.h>.
(log2f): Define using libm_alias_float, or libm_alias_float_other
if [SHARED].
* sysdeps/i386/i686/fpu/multiarch/e_logf.c: Include
<libm-alias-float.h>.
(logf): Define using libm_alias_float, or libm_alias_float_other
if [SHARED].
* sysdeps/i386/i686/fpu/multiarch/e_powf.c: Include
<libm-alias-float.h>.
(powf): Define using libm_alias_float, or libm_alias_float_other
if [SHARED].
* sysdeps/i386/i686/fpu/multiarch/s_cosf.c: Include
<libm-alias-float.h>.
(cosf): Define using libm_alias_float.
* sysdeps/i386/i686/fpu/multiarch/s_sincosf.c: Include
<libm-alias-float.h>.
(sincosf): Define using libm_alias_float.
* sysdeps/i386/i686/fpu/multiarch/s_sinf.c: Include
<libm-alias-float.h>.
(sinf): Define using libm_alias_float.
* sysdeps/i386/i686/fpu/s_fmaxf.S: Include <libm-alias-float.h>.
(fmaxf): Define using libm_alias_float.
* sysdeps/i386/i686/fpu/s_fminf.S: Include <libm-alias-float.h>.
(fminf): Define using libm_alias_float.
* sysdeps/i386/i686/multiarch/s_fmaf.c: Include
<libm-alias-float.h>.
(fmaf): Define using libm_alias_float.
As discussed in
<https://sourceware.org/ml/libc-alpha/2016-05/msg00577.html>, TS
18661-1 disallows ceil, floor, round and trunc functions from raising
the "inexact" exception, in accordance with general IEEE 754 semantics
for when that exception is raised. Fixing this for x87 floating point
is more complicated than for the other versions of these functions,
because they use the frndint instruction that raises "inexact" and
this can only be avoided by saving and restoring the whole
floating-point environment.
As I noted in
<https://sourceware.org/ml/libc-alpha/2016-06/msg00128.html>, I have
now implemented a GCC option -fno-fp-int-builtin-inexact for GCC 7,
such that GCC will inline these functions on x86, without caring about
"inexact", when the default -ffp-int-builtin-inexact is in effect.
This allows users to get optimized code depending on the options they
pass to the compiler, while making the out-of-line functions follow TS
18661-1 semantics and avoid "inexact".
This patch duly fixes the out-of-line floor function implementations
to avoid "inexact", in the same way as the nearbyint implementations.
I do not know how the performance of implementations such as these
based on saving the environment and changing the rounding mode
temporarily compares to that of the C versions or SSE 4.1 versions (of
course, for 32-bit x86 SSE implementations still need to get the
return value in an x87 register); it's entirely possible other
implementations could be faster in some cases.
Tested for x86_64 and x86.
[BZ #15479]
* sysdeps/i386/fpu/s_floor.S (__floor): Save and restore
floating-point environment rather than just control word.
* sysdeps/i386/fpu/s_floorf.S (__floorf): Likewise.
* sysdeps/i386/fpu/s_floorl.S (__floorl): Save and restore
floating-point environment, with "invalid" exceptions merged in,
rather than just control word.
* sysdeps/x86_64/fpu/s_floorl.S (__floorl): Likewise.
* math/libm-test.inc (floor_test_data): Do not allow spurious
"inexact" exceptions.
