1 | /* Conversion routines from GCC internal float representation to MPFR. |
2 | Copyright (C) 2010-2023 Free Software Foundation, Inc. |
3 | |
4 | This file is part of GCC. |
5 | |
6 | GCC is free software; you can redistribute it and/or modify it under |
7 | the terms of the GNU General Public License as published by the Free |
8 | Software Foundation; either version 3, or (at your option) any later |
9 | version. |
10 | |
11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
14 | for more details. |
15 | |
16 | You should have received a copy of the GNU General Public License |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ |
19 | |
20 | #include "config.h" |
21 | #include "system.h" |
22 | #include "coretypes.h" |
23 | #include "tree.h" |
24 | #include "realmpfr.h" |
25 | #include "stor-layout.h" |
26 | |
27 | /* Convert from REAL_VALUE_TYPE to MPFR. The caller is responsible |
28 | for initializing and clearing the MPFR parameter. */ |
29 | |
30 | void |
31 | mpfr_from_real (mpfr_ptr m, const REAL_VALUE_TYPE *r, mpfr_rnd_t rndmode) |
32 | { |
33 | /* We use a string as an intermediate type. */ |
34 | char buf[128]; |
35 | int ret; |
36 | |
37 | /* Take care of Infinity and NaN. */ |
38 | if (r->cl == rvc_inf) |
39 | { |
40 | mpfr_set_inf (m, r->sign == 1 ? -1 : 1); |
41 | return; |
42 | } |
43 | |
44 | if (r->cl == rvc_nan) |
45 | { |
46 | mpfr_set_nan (m); |
47 | return; |
48 | } |
49 | |
50 | real_to_hexadecimal (buf, r, sizeof (buf), 0, 1); |
51 | /* mpfr_set_str() parses hexadecimal floats from strings in the same |
52 | format that GCC will output them. Nothing extra is needed. */ |
53 | ret = mpfr_set_str (m, buf, 16, rndmode); |
54 | gcc_assert (ret == 0); |
55 | } |
56 | |
57 | /* Convert from MPFR to REAL_VALUE_TYPE, for a given format FORMAT and |
58 | rounding mode RNDMODE. FORMAT is only relevant if M is a NaN. */ |
59 | |
60 | void |
61 | real_from_mpfr (REAL_VALUE_TYPE *r, mpfr_srcptr m, const real_format *format, |
62 | mpfr_rnd_t rndmode) |
63 | { |
64 | /* We use a string as an intermediate type. */ |
65 | char buf[128], *rstr; |
66 | mpfr_exp_t exp; |
67 | |
68 | /* Take care of Infinity and NaN. */ |
69 | if (mpfr_inf_p (m)) |
70 | { |
71 | *r = dconstinf; |
72 | if (mpfr_sgn (m) < 0) |
73 | *r = real_value_negate (r); |
74 | return; |
75 | } |
76 | |
77 | if (mpfr_nan_p (m)) |
78 | { |
79 | real_nan (r, "" , 1, format); |
80 | return; |
81 | } |
82 | |
83 | rstr = mpfr_get_str (NULL, &exp, 16, 0, m, rndmode); |
84 | |
85 | /* The additional 12 chars add space for the sprintf below. This |
86 | leaves 6 digits for the exponent which is supposedly enough. */ |
87 | gcc_assert (rstr != NULL && strlen (rstr) < sizeof (buf) - 12); |
88 | |
89 | /* REAL_VALUE_ATOF expects the exponent for mantissa * 2**exp, |
90 | mpfr_get_str returns the exponent for mantissa * 16**exp, adjust |
91 | for that. */ |
92 | exp *= 4; |
93 | |
94 | if (rstr[0] == '-') |
95 | sprintf (s: buf, format: "-0x.%sp%d" , &rstr[1], (int) exp); |
96 | else |
97 | sprintf (s: buf, format: "0x.%sp%d" , rstr, (int) exp); |
98 | |
99 | mpfr_free_str (rstr); |
100 | |
101 | real_from_string (r, buf); |
102 | } |
103 | |
104 | /* Convert from MPFR to REAL_VALUE_TYPE, for a given type TYPE and rounding |
105 | mode RNDMODE. TYPE is only relevant if M is a NaN. */ |
106 | |
107 | void |
108 | real_from_mpfr (REAL_VALUE_TYPE *r, mpfr_srcptr m, tree type, |
109 | mpfr_rnd_t rndmode) |
110 | { |
111 | real_from_mpfr (r, m, format: type ? REAL_MODE_FORMAT (TYPE_MODE (type)) : NULL, |
112 | rndmode); |
113 | } |
114 | |
115 | |