1/* Round long double value to long long int.
2 Copyright (C) 1997-2017 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
5 Jakub Jelinek <jj@ultra.linux.cz>, 1999.
6
7 The GNU C Library is free software; you can redistribute it and/or
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.
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
15 Lesser General Public License for more details.
16
17 You should have received a copy of the GNU Lesser General Public
18 License along with the GNU C Library; if not, see
19 <http://www.gnu.org/licenses/>. */
20
21#include <fenv.h>
22#include <limits.h>
23#include <math.h>
24
25#include <math_private.h>
26#include <fix-fp-int-convert-overflow.h>
27
28long long int
29__llroundl (_Float128 x)
30{
31 int64_t j0;
32 u_int64_t i1, i0;
33 long long int result;
34 int sign;
35
36 GET_LDOUBLE_WORDS64 (i0, i1, x);
37 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
38 sign = (i0 & 0x8000000000000000ULL) != 0 ? -1 : 1;
39 i0 &= 0x0000ffffffffffffLL;
40 i0 |= 0x0001000000000000LL;
41
42 if (j0 < 48)
43 {
44 if (j0 < 0)
45 return j0 < -1 ? 0 : sign;
46 else
47 {
48 i0 += 0x0000800000000000LL >> j0;
49 result = i0 >> (48 - j0);
50 }
51 }
52 else if (j0 < (int32_t) (8 * sizeof (long long int)) - 1)
53 {
54 if (j0 >= 112)
55 result = ((long long int) i0 << (j0 - 48)) | (i1 << (j0 - 112));
56 else
57 {
58 u_int64_t j = i1 + (0x8000000000000000ULL >> (j0 - 48));
59 if (j < i1)
60 ++i0;
61
62 if (j0 == 48)
63 result = (long long int) i0;
64 else
65 {
66 result = ((long long int) i0 << (j0 - 48)) | (j >> (112 - j0));
67#ifdef FE_INVALID
68 if (sign == 1 && result == LLONG_MIN)
69 /* Rounding brought the value out of range. */
70 feraiseexcept (FE_INVALID);
71#endif
72 }
73 }
74 }
75 else
76 {
77 /* The number is too large. Unless it rounds to LLONG_MIN,
78 FE_INVALID must be raised and the return value is
79 unspecified. */
80#ifdef FE_INVALID
81 if (FIX_LDBL_LLONG_CONVERT_OVERFLOW
82 && !(sign == -1 && x > (_Float128) LLONG_MIN - L(0.5)))
83 {
84 feraiseexcept (FE_INVALID);
85 return sign == 1 ? LLONG_MAX : LLONG_MIN;
86 }
87 else if (!FIX_LDBL_LLONG_CONVERT_OVERFLOW
88 && x <= (_Float128) LLONG_MIN - L(0.5))
89 {
90 /* If truncation produces LLONG_MIN, the cast will not raise
91 the exception, but may raise "inexact". */
92 feraiseexcept (FE_INVALID);
93 return LLONG_MIN;
94 }
95#endif
96 return (long long int) x;
97 }
98
99 return sign * result;
100}
101
102weak_alias (__llroundl, llroundl)
103