1/* Subtract long double (ldbl-128) values, narrowing the result to
2 float, using soft-fp.
3 Copyright (C) 2018-2024 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20#define f32subf64x __hide_f32subf64x
21#define f32subf128 __hide_f32subf128
22#include <math.h>
23#undef f32subf64x
24#undef f32subf128
25
26#include <math-narrow.h>
27#include <soft-fp.h>
28#include <single.h>
29#include <quad.h>
30
31float
32__fsubl (_Float128 x, _Float128 y)
33{
34 FP_DECL_EX;
35 FP_DECL_Q (X);
36 FP_DECL_Q (Y);
37 FP_DECL_Q (R);
38 FP_DECL_S (RN);
39 float ret;
40
41 FP_INIT_ROUNDMODE;
42 FP_UNPACK_SEMIRAW_Q (X, x);
43 FP_UNPACK_SEMIRAW_Q (Y, y);
44 FP_SUB_Q (R, X, Y);
45#if _FP_W_TYPE_SIZE < 64
46 FP_TRUNC (S, Q, 1, 4, RN, R);
47#else
48 FP_TRUNC (S, Q, 1, 2, RN, R);
49#endif
50 FP_PACK_SEMIRAW_S (ret, RN);
51 FP_HANDLE_EXCEPTIONS;
52 CHECK_NARROW_SUB (ret, x, y);
53 return ret;
54}
55libm_alias_float_ldouble (sub)
56

source code of glibc/sysdeps/ieee754/soft-fp/s_fsubl.c