glibc/math/e_scalb.c
Wilco Dijkstra 220622dde5 Add libm_alias_finite for _finite symbols
This patch adds a new macro, libm_alias_finite, to define all _finite
symbol.  It sets all _finite symbol as compat symbol based on its first
version (obtained from the definition at built generated first-versions.h).

The <fn>f128_finite symbols were introduced in GLIBC 2.26 and so need
special treatment in code that is shared between long double and float128.
It is done by adding a list, similar to internal symbol redifinition,
on sysdeps/ieee754/float128/float128_private.h.

Alpha also needs some tricky changes to ensure we still emit 2 compat
symbols for sqrt(f).

Passes buildmanyglibc.

Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2020-01-03 10:02:04 -03:00

55 lines
1.6 KiB
C

/* Copyright (C) 2011-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <math.h>
#include <math_private.h>
#include <libm-alias-finite.h>
static double
__attribute__ ((noinline))
invalid_fn (double x, double fn)
{
if (rint (fn) != fn)
return (fn - fn) / (fn - fn);
else if (fn > 65000.0)
return __scalbn (x, 65000);
else
return __scalbn (x,-65000);
}
double
__ieee754_scalb (double x, double fn)
{
if (__glibc_unlikely (isnan (x)))
return x * fn;
if (__glibc_unlikely (!isfinite (fn)))
{
if (isnan (fn) || fn > 0.0)
return x * fn;
if (x == 0.0)
return x;
return x / -fn;
}
if (__glibc_unlikely (fabs (fn) >= 0x1p31 || (double) (int) fn != fn))
return invalid_fn (x, fn);
return __scalbn (x, (int) fn);
}
libm_alias_finite (__ieee754_scalb, __scalb)