1/* Truncate argument to nearest integral value not larger than the argument.
2 Copyright (C) 1997-2020 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 <https://www.gnu.org/licenses/>. */
20
21#define NO_MATH_REDIRECT
22#include <math.h>
23
24#include <math_private.h>
25#include <libm-alias-ldouble.h>
26#include <math-use-builtins.h>
27
28
29_Float128
30__truncl (_Float128 x)
31{
32#if USE_TRUNCL_BUILTIN
33 return __builtin_truncl (x);
34#else
35 /* Use generic implementation. */
36 int32_t j0;
37 uint64_t i0, i1, sx;
38
39 GET_LDOUBLE_WORDS64 (i0, i1, x);
40 sx = i0 & 0x8000000000000000ULL;
41 j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
42 if (j0 < 48)
43 {
44 if (j0 < 0)
45 /* The magnitude of the number is < 1 so the result is +-0. */
46 SET_LDOUBLE_WORDS64 (x, sx, 0);
47 else
48 SET_LDOUBLE_WORDS64 (x, i0 & ~(0x0000ffffffffffffLL >> j0), 0);
49 }
50 else if (j0 > 111)
51 {
52 if (j0 == 0x4000)
53 /* x is inf or NaN. */
54 return x + x;
55 }
56 else
57 {
58 SET_LDOUBLE_WORDS64 (x, i0, i1 & ~(0xffffffffffffffffULL >> (j0 - 48)));
59 }
60
61 return x;
62#endif /* ! USE_TRUNCL_BUILTIN */
63}
64libm_alias_ldouble (__trunc, trunc)
65