1 /* Set NaN payload. dbl-64 version.
2 Copyright (C) 2016-2021 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
20 #include <math_private.h>
21 #include <libm-alias-double.h>
22 #include <nan-high-order-bit.h>
25 #define SET_HIGH_BIT (HIGH_ORDER_BIT_IS_SET_FOR_SNAN ? SIG : !SIG)
27 #define PAYLOAD_DIG 51
28 #define EXPLICIT_MANT_DIG 52
31 FUNC (double *x
, double payload
)
34 EXTRACT_WORDS (hx
, lx
, payload
);
35 int exponent
= hx
>> (EXPLICIT_MANT_DIG
- 32);
36 /* Test if argument is (a) negative or too large; (b) too small,
37 except for 0 when allowed; (c) not an integer. */
38 if (exponent
>= BIAS
+ PAYLOAD_DIG
39 || (exponent
< BIAS
&& !(SET_HIGH_BIT
&& hx
== 0 && lx
== 0)))
41 INSERT_WORDS (*x
, 0, 0);
44 int shift
= BIAS
+ EXPLICIT_MANT_DIG
- exponent
;
46 ? (lx
& ((1U << shift
) - 1)) != 0
47 : (lx
!= 0 || (hx
& ((1U << (shift
- 32)) - 1)) != 0))
49 INSERT_WORDS (*x
, 0, 0);
54 hx
&= (1U << (EXPLICIT_MANT_DIG
- 32)) - 1;
55 hx
|= 1U << (EXPLICIT_MANT_DIG
- 32);
58 lx
= hx
>> (shift
- 32);
63 lx
= (lx
>> shift
) | (hx
<< (32 - shift
));
67 hx
|= 0x7ff00000 | (SET_HIGH_BIT
? 0x80000 : 0);
68 INSERT_WORDS (*x
, hx
, lx
);