glibc/sysdeps/ieee754/soft-fp/s_fsub.c

57 lines
1.6 KiB
C

/* Subtract double values, narrowing the result to float, using soft-fp.
Copyright (C) 2018-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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/>. */
#define f32subf64 __hide_f32subf64
#define f32subf32x __hide_f32subf32x
#define fsubl __hide_fsubl
#include <math.h>
#undef f32subf64
#undef f32subf32x
#undef fsubl
#include <math-narrow.h>
#include <soft-fp.h>
#include <single.h>
#include <double.h>
float
__fsub (double x, double y)
{
FP_DECL_EX;
FP_DECL_D (X);
FP_DECL_D (Y);
FP_DECL_D (R);
FP_DECL_S (RN);
float ret;
FP_INIT_ROUNDMODE;
FP_UNPACK_SEMIRAW_D (X, x);
FP_UNPACK_SEMIRAW_D (Y, y);
FP_SUB_D (R, X, Y);
#if _FP_W_TYPE_SIZE < _FP_FRACBITS_D
FP_TRUNC (S, D, 1, 2, RN, R);
#else
FP_TRUNC (S, D, 1, 1, RN, R);
#endif
FP_PACK_SEMIRAW_S (ret, RN);
FP_HANDLE_EXCEPTIONS;
CHECK_NARROW_SUB (ret, x, y);
return ret;
}
libm_alias_float_double (sub)