1 | /* Set NaN payload. ldbl-128ibm version. |
2 | Copyright (C) 2016-2022 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
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. |
9 | |
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. |
14 | |
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/>. */ |
18 | |
19 | #include <math.h> |
20 | #include <math_private.h> |
21 | #include <nan-high-order-bit.h> |
22 | #include <stdint.h> |
23 | |
24 | #define SET_HIGH_BIT (HIGH_ORDER_BIT_IS_SET_FOR_SNAN ? SIG : !SIG) |
25 | #define BIAS 0x3ff |
26 | #define PAYLOAD_DIG 51 |
27 | #define EXPLICIT_MANT_DIG 52 |
28 | |
29 | int |
30 | FUNC (long double *x, long double payload) |
31 | { |
32 | double hi, lo; |
33 | uint64_t hx, lx; |
34 | |
35 | ldbl_unpack (payload, &hi, &lo); |
36 | EXTRACT_WORDS64 (hx, hi); |
37 | EXTRACT_WORDS64 (lx, lo); |
38 | int exponent = hx >> EXPLICIT_MANT_DIG; |
39 | /* Test if argument is (a) negative or too large; (b) too small, |
40 | except for 0 when allowed; (c) not an integer. All valid |
41 | arguments have the low part zero. */ |
42 | if ((lx & 0x7fffffffffffffffULL) != 0 |
43 | || exponent >= BIAS + PAYLOAD_DIG |
44 | || (exponent < BIAS && !(SET_HIGH_BIT && hx == 0)) |
45 | || (hx & ((1ULL << (BIAS + EXPLICIT_MANT_DIG - exponent)) - 1)) != 0) |
46 | { |
47 | *x = 0.0L; |
48 | return 1; |
49 | } |
50 | if (hx != 0) |
51 | { |
52 | hx &= (1ULL << EXPLICIT_MANT_DIG) - 1; |
53 | hx |= 1ULL << EXPLICIT_MANT_DIG; |
54 | hx >>= BIAS + EXPLICIT_MANT_DIG - exponent; |
55 | } |
56 | hx |= 0x7ff0000000000000ULL | (SET_HIGH_BIT ? 0x8000000000000ULL : 0); |
57 | INSERT_WORDS64 (hi, hx); |
58 | *x = ldbl_pack (hi, 0.0); |
59 | return 0; |
60 | } |
61 | |