math/w_exp_compat.c

   1 /* Copyright (C) 2011-2024 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <math.h>
  19 #include <math_private.h>
  20 #include <math-svid-compat.h>
  21 #include <libm-alias-double.h>
  22
  23 #if LIBM_SVID_COMPAT && (SHLIB_COMPAT (libm, GLIBC_2_0, GLIBC_2_29) \
  24                          || defined NO_LONG_DOUBLE \
  25                          || defined LONG_DOUBLE_COMPAT)
  26 /* wrapper exp */
  27 double
  28 __exp_compat (double x)
  29 {
  30   double z = __ieee754_exp (x);
  31   if (__builtin_expect (!isfinite (z) || z == 0, 0)
  32       && isfinite (x) && _LIB_VERSION != _IEEE_)
  33     return __kernel_standard (x, x, 6 + !!signbit (x));
  34
  35   return z;
  36 }
  37 # if SHLIB_COMPAT (libm, GLIBC_2_0, GLIBC_2_29)
  38 compat_symbol (libm, __exp_compat, exp, GLIBC_2_0);
  39 # endif
  40 # ifdef NO_LONG_DOUBLE
  41 weak_alias (__exp_compat, expl)
  42 # endif
  43 # ifdef LONG_DOUBLE_COMPAT
  44 /* Work around gas bug "multiple versions for symbol".  */
  45 weak_alias (__exp_compat, __exp_compat_alias)
  46
  47 LONG_DOUBLE_COMPAT_CHOOSE_libm_expl (
  48   compat_symbol (libm, __exp_compat_alias, expl, FIRST_VERSION_libm_expl), );
  49 # endif
  50 #endif