1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
|
/* Set NaN payload. ldbl-128 version.
Copyright (C) 2016-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <math.h>
#include <math_private.h>
#include <libm-alias-ldouble.h>
#include <nan-high-order-bit.h>
#include <stdint.h>
#define SET_HIGH_BIT (HIGH_ORDER_BIT_IS_SET_FOR_SNAN ? SIG : !SIG)
#define BIAS 0x3fff
#define PAYLOAD_DIG 111
#define EXPLICIT_MANT_DIG 112
int
FUNC (_Float128 *x, _Float128 payload)
{
uint64_t hx, lx;
GET_LDOUBLE_WORDS64 (hx, lx, payload);
int exponent = hx >> (EXPLICIT_MANT_DIG - 64);
/* Test if argument is (a) negative or too large; (b) too small,
except for 0 when allowed; (c) not an integer. */
if (exponent >= BIAS + PAYLOAD_DIG
|| (exponent < BIAS && !(SET_HIGH_BIT && hx == 0 && lx == 0)))
{
SET_LDOUBLE_WORDS64 (*x, 0, 0);
return 1;
}
int shift = BIAS + EXPLICIT_MANT_DIG - exponent;
if (shift < 64
? (lx & ((1ULL << shift) - 1)) != 0
: (lx != 0 || (hx & ((1ULL << (shift - 64)) - 1)) != 0))
{
SET_LDOUBLE_WORDS64 (*x, 0, 0);
return 1;
}
if (exponent != 0)
{
hx &= (1ULL << (EXPLICIT_MANT_DIG - 64)) - 1;
hx |= 1ULL << (EXPLICIT_MANT_DIG - 64);
if (shift >= 64)
{
lx = hx >> (shift - 64);
hx = 0;
}
else if (shift != 0)
{
lx = (lx >> shift) | (hx << (64 - shift));
hx >>= shift;
}
}
hx |= 0x7fff000000000000ULL | (SET_HIGH_BIT ? 0x800000000000ULL : 0);
SET_LDOUBLE_WORDS64 (*x, hx, lx);
return 0;
}
|
