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Commit | Line | Data |
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dfd2257a UD |
1 | /* Round argument to nearest integral value according to current rounding |
2 | direction. | |
04277e02 | 3 | Copyright (C) 1997-2019 Free Software Foundation, Inc. |
dfd2257a UD |
4 | This file is part of the GNU C Library. |
5 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. | |
6 | ||
7 | The GNU C Library is free software; you can redistribute it and/or | |
41bdb6e2 AJ |
8 | modify it under the terms of the GNU Lesser General Public |
9 | License as published by the Free Software Foundation; either | |
10 | version 2.1 of the License, or (at your option) any later version. | |
dfd2257a UD |
11 | |
12 | The GNU C Library is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
41bdb6e2 | 15 | Lesser General Public License for more details. |
dfd2257a | 16 | |
41bdb6e2 | 17 | You should have received a copy of the GNU Lesser General Public |
59ba27a6 PE |
18 | License along with the GNU C Library; if not, see |
19 | <http://www.gnu.org/licenses/>. */ | |
dfd2257a | 20 | |
d0d286d3 JM |
21 | #include <fenv.h> |
22 | #include <limits.h> | |
dfd2257a UD |
23 | #include <math.h> |
24 | ||
1ed0291c | 25 | #include <math_private.h> |
86f9568a | 26 | #include <libm-alias-ldouble.h> |
dfd2257a UD |
27 | |
28 | static const long double two63[2] = | |
29 | { | |
30 | 9.223372036854775808000000e+18, /* 0x403E, 0x00000000, 0x00000000 */ | |
31 | -9.223372036854775808000000e+18 /* 0xC03E, 0x00000000, 0x00000000 */ | |
32 | }; | |
33 | ||
34 | ||
35 | long int | |
36 | __lrintl (long double x) | |
37 | { | |
38 | int32_t se,j0; | |
24ab7723 | 39 | uint32_t i0, i1; |
dfd2257a | 40 | long int result; |
54142c44 | 41 | long double w; |
dfd2257a UD |
42 | long double t; |
43 | int sx; | |
44 | ||
45 | GET_LDOUBLE_WORDS (se, i0, i1, x); | |
46 | ||
47 | sx = (se >> 15) & 1; | |
48 | j0 = (se & 0x7fff) - 0x3fff; | |
49 | ||
50 | if (j0 < 31) | |
51 | { | |
d0d286d3 JM |
52 | #if defined FE_INVALID || defined FE_INEXACT |
53 | /* X < LONG_MAX + 1 implied by J0 < 31. */ | |
54 | if (sizeof (long int) == 4 | |
55 | && x > (long double) LONG_MAX) | |
56 | { | |
57 | /* In the event of overflow we must raise the "invalid" | |
58 | exception, but not "inexact". */ | |
59 | t = __nearbyintl (x); | |
60 | feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID); | |
61 | } | |
62 | else | |
63 | #endif | |
64 | { | |
65 | w = two63[sx] + x; | |
66 | t = w - two63[sx]; | |
67 | } | |
6624dbc0 UD |
68 | GET_LDOUBLE_WORDS (se, i0, i1, t); |
69 | j0 = (se & 0x7fff) - 0x3fff; | |
dfd2257a | 70 | |
6624dbc0 | 71 | result = (j0 < 0 ? 0 : i0 >> (31 - j0)); |
dfd2257a | 72 | } |
cc3fa755 | 73 | else if (j0 < (int32_t) (8 * sizeof (long int)) - 1) |
dfd2257a UD |
74 | { |
75 | if (j0 >= 63) | |
76 | result = ((long int) i0 << (j0 - 31)) | (i1 << (j0 - 63)); | |
77 | else | |
78 | { | |
d0d286d3 JM |
79 | #if defined FE_INVALID || defined FE_INEXACT |
80 | /* X < LONG_MAX + 1 implied by J0 < 63. */ | |
81 | if (sizeof (long int) == 8 | |
82 | && x > (long double) LONG_MAX) | |
83 | { | |
84 | /* In the event of overflow we must raise the "invalid" | |
85 | exception, but not "inexact". */ | |
86 | t = __nearbyintl (x); | |
87 | feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID); | |
88 | } | |
89 | else | |
90 | #endif | |
91 | { | |
92 | w = two63[sx] + x; | |
93 | t = w - two63[sx]; | |
94 | } | |
dfd2257a UD |
95 | GET_LDOUBLE_WORDS (se, i0, i1, t); |
96 | j0 = (se & 0x7fff) - 0x3fff; | |
97 | ||
3eb61415 UD |
98 | if (j0 == 31) |
99 | result = (long int) i0; | |
100 | else | |
101 | result = ((long int) i0 << (j0 - 31)) | (i1 >> (63 - j0)); | |
dfd2257a UD |
102 | } |
103 | } | |
104 | else | |
105 | { | |
d0d286d3 JM |
106 | /* The number is too large. Unless it rounds to LONG_MIN, |
107 | FE_INVALID must be raised and the return value is | |
108 | unspecified. */ | |
109 | #if defined FE_INVALID || defined FE_INEXACT | |
110 | if (sizeof (long int) == 4 | |
111 | && x < (long double) LONG_MIN | |
112 | && x > (long double) LONG_MIN - 1.0L) | |
113 | { | |
114 | /* If truncation produces LONG_MIN, the cast will not raise | |
115 | the exception, but may raise "inexact". */ | |
116 | t = __nearbyintl (x); | |
117 | feraiseexcept (t == LONG_MIN ? FE_INEXACT : FE_INVALID); | |
118 | return LONG_MIN; | |
119 | } | |
120 | #endif | |
dfd2257a UD |
121 | return (long int) x; |
122 | } | |
123 | ||
124 | return sx ? -result : result; | |
125 | } | |
126 | ||
86f9568a | 127 | libm_alias_ldouble (__lrint, lrint) |