1 /* mpfr_set_machine_rnd_mode -- set the rounding mode for machine floats
2
3 Copyright 1999, 2001-2002, 2006-2023 Free Software Foundation, Inc.
4 Contributed by the AriC and Caramba projects, INRIA.
5
6 This file is part of the GNU MPFR Library.
7
8 The GNU MPFR Library is free software; you can redistribute it and/or modify
9 it under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or (at your
11 option) any later version.
12
13 The GNU MPFR Library is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
16 License for more details.
17
18 You should have received a copy of the GNU Lesser General Public License
19 along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
20 https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
21 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
22
23 #include "mpfr-test.h"
24
25 /* It is important to test each FE_* macro -- see the ISO C99 standard.
26 For instance, with some ARM implementations, only FE_TONEAREST may
27 be defined. */
28
29 /* sets the machine rounding mode to the value rnd_mode */
30 int
mpfr_set_machine_rnd_mode(mpfr_rnd_t rnd_mode)31 mpfr_set_machine_rnd_mode (mpfr_rnd_t rnd_mode)
32 {
33 switch (rnd_mode)
34 {
35 case MPFR_RNDN:
36 return
37 #if defined (MPFR_HAVE_FESETROUND) && defined (FE_TONEAREST)
38 fesetround(FE_TONEAREST)
39 #else
40 -1
41 #endif
42 ;
43 case MPFR_RNDZ:
44 return
45 #if defined (MPFR_HAVE_FESETROUND) && defined (FE_TOWARDZERO)
46 fesetround(FE_TOWARDZERO)
47 #else
48 -1
49 #endif
50 ;
51 case MPFR_RNDU:
52 return
53 #if defined (MPFR_HAVE_FESETROUND) && defined (FE_UPWARD)
54 fesetround(FE_UPWARD)
55 #else
56 -1
57 #endif
58 ;
59 case MPFR_RNDD:
60 return
61 #if defined (MPFR_HAVE_FESETROUND) && defined (FE_DOWNWARD)
62 fesetround(FE_DOWNWARD)
63 #else
64 -1
65 #endif
66 ;
67 default:
68 return -1;
69 }
70 }
71