1/* Round argument to nearest integral value according to current rounding
2 direction.
3 Copyright (C) 1997-2017 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
6 Jakub Jelinek <jj@ultra.linux.cz>, 1999.
7
8 The GNU C Library is free software; you can redistribute it and/or
9 modify it under the terms of the GNU Lesser General Public
10 License as published by the Free Software Foundation; either
11 version 2.1 of the License, or (at your option) any later version.
12
13 The GNU C Library is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
17
18 You should have received a copy of the GNU Lesser General Public
19 License along with the GNU C Library; if not, see
20 <http://www.gnu.org/licenses/>. */
21
22#include <fenv.h>
23#include <limits.h>
24#include <math.h>
25
26#include <math_private.h>
27#include <fix-fp-int-convert-overflow.h>
28
29static const _Float128 two112[2] =
30{
31 L(5.19229685853482762853049632922009600E+33), /* 0x406F000000000000, 0 */
32 L(-5.19229685853482762853049632922009600E+33) /* 0xC06F000000000000, 0 */
33};
34
35long int
36__lrintl (_Float128 x)
37{
38 int32_t j0;
39 u_int64_t i0,i1;
40 _Float128 w;
41 _Float128 t;
42 long int result;
43 int sx;
44
45 GET_LDOUBLE_WORDS64 (i0, i1, x);
46 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
47 sx = i0 >> 63;
48 i0 &= 0x0000ffffffffffffLL;
49 i0 |= 0x0001000000000000LL;
50
51 if (j0 < (int32_t) (8 * sizeof (long int)) - 1)
52 {
53 if (j0 < 48)
54 {
55#if defined FE_INVALID || defined FE_INEXACT
56 /* X < LONG_MAX + 1 implied by J0 < 31. */
57 if (sizeof (long int) == 4
58 && x > (_Float128) LONG_MAX)
59 {
60 /* In the event of overflow we must raise the "invalid"
61 exception, but not "inexact". */
62 t = __nearbyintl (x);
63 feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID);
64 }
65 else
66#endif
67 {
68 w = two112[sx] + x;
69 t = w - two112[sx];
70 }
71 GET_LDOUBLE_WORDS64 (i0, i1, t);
72 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
73 i0 &= 0x0000ffffffffffffLL;
74 i0 |= 0x0001000000000000LL;
75
76 result = (j0 < 0 ? 0 : i0 >> (48 - j0));
77 }
78 else if (j0 >= 112)
79 result = ((long int) i0 << (j0 - 48)) | (i1 << (j0 - 112));
80 else
81 {
82#if defined FE_INVALID || defined FE_INEXACT
83 /* X < LONG_MAX + 1 implied by J0 < 63. */
84 if (sizeof (long int) == 8
85 && x > (_Float128) LONG_MAX)
86 {
87 /* In the event of overflow we must raise the "invalid"
88 exception, but not "inexact". */
89 t = __nearbyintl (x);
90 feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID);
91 }
92 else
93#endif
94 {
95 w = two112[sx] + x;
96 t = w - two112[sx];
97 }
98 GET_LDOUBLE_WORDS64 (i0, i1, t);
99 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
100 i0 &= 0x0000ffffffffffffLL;
101 i0 |= 0x0001000000000000LL;
102
103 if (j0 == 48)
104 result = (long int) i0;
105 else
106 result = ((long int) i0 << (j0 - 48)) | (i1 >> (112 - j0));
107 }
108 }
109 else
110 {
111 /* The number is too large. Unless it rounds to LONG_MIN,
112 FE_INVALID must be raised and the return value is
113 unspecified. */
114#if defined FE_INVALID || defined FE_INEXACT
115 if (x < (_Float128) LONG_MIN
116 && x > (_Float128) LONG_MIN - 1)
117 {
118 /* If truncation produces LONG_MIN, the cast will not raise
119 the exception, but may raise "inexact". */
120 t = __nearbyintl (x);
121 feraiseexcept (t == LONG_MIN ? FE_INEXACT : FE_INVALID);
122 return LONG_MIN;
123 }
124 else if (FIX_LDBL_LONG_CONVERT_OVERFLOW && x != (_Float128) LONG_MIN)
125 {
126 feraiseexcept (FE_INVALID);
127 return sx == 0 ? LONG_MAX : LONG_MIN;
128 }
129
130#endif
131 return (long int) x;
132 }
133
134 return sx ? -result : result;
135}
136
137weak_alias (__lrintl, lrintl)
138