1 /* Subtract long double (ldbl-128) values, narrowing the result to
2 double, using soft-fp.
3 Copyright (C) 2018-2022 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 f32xsubf64x __hide_f32xsubf64x
21 #define f32xsubf128 __hide_f32xsubf128
22 #define f64subf64x __hide_f64subf64x
23 #define f64subf128 __hide_f64subf128
24 #include <math.h>
25 #undef f32xsubf64x
26 #undef f32xsubf128
27 #undef f64subf64x
28 #undef f64subf128
29
30 #include <math-narrow.h>
31 #include <soft-fp.h>
32 #include <double.h>
33 #include <quad.h>
34
35 double
__dsubl(_Float128 x,_Float128 y)36 __dsubl (_Float128 x, _Float128 y)
37 {
38 FP_DECL_EX;
39 FP_DECL_Q (X);
40 FP_DECL_Q (Y);
41 FP_DECL_Q (R);
42 FP_DECL_D (RN);
43 double ret;
44
45 FP_INIT_ROUNDMODE;
46 FP_UNPACK_SEMIRAW_Q (X, x);
47 FP_UNPACK_SEMIRAW_Q (Y, y);
48 FP_SUB_Q (R, X, Y);
49 #if _FP_W_TYPE_SIZE < 64
50 FP_TRUNC (D, Q, 2, 4, RN, R);
51 #else
52 FP_TRUNC (D, Q, 1, 2, RN, R);
53 #endif
54 FP_PACK_SEMIRAW_D (ret, RN);
55 FP_HANDLE_EXCEPTIONS;
56 CHECK_NARROW_SUB (ret, x, y);
57 return ret;
58 }
59 libm_alias_double_ldouble (sub)
60