sysdeps/riscv/rvd/fix-float-double-convert-nan.h

   1 /* Fix for conversion of float NAN to double.  RISC-V version..
   2    Copyright (C) 2022-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef FIX_FLOAT_DOUBLE_CONVERT_NAN_H
  20 #define FIX_FLOAT_DOUBLE_CONVERT_NAN_H
  21
  22 #include <math.h>
  23
  24 /* RISC-V rvd instructions do not preserve the signbit of NAN
  25    when converting from float to double.  */
  26 static inline double
  27 keep_sign_conversion (float flt)
  28 {
  29   if (__glibc_unlikely (isnan (flt)))
  30   {
  31     float x = copysignf (1.f, flt);
  32     return copysign ((double) flt, (double) x);
  33   }
  34   return flt;
  35 }
  36
  37 #endif