1 | /* Get NaN payload. ldbl-128 version. |
2 | Copyright (C) 2016-2023 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 <libm-alias-ldouble.h> |
22 | #include <stdint.h> |
23 | |
24 | _Float128 |
25 | __getpayloadl (const _Float128 *x) |
26 | { |
27 | uint64_t hx, lx; |
28 | GET_LDOUBLE_WORDS64 (hx, lx, *x); |
29 | if ((hx & 0x7fff000000000000ULL) != 0x7fff000000000000ULL |
30 | || ((hx & 0xffffffffffffULL) | lx) == 0) |
31 | return -1; |
32 | hx &= 0x7fffffffffffULL; |
33 | /* Construct the representation of the return value directly, since |
34 | 128-bit integers may not be available. */ |
35 | int lz; |
36 | if (hx == 0) |
37 | { |
38 | if (lx == 0) |
39 | return 0.0L; |
40 | else |
41 | lz = __builtin_clzll (lx) + 64; |
42 | } |
43 | else |
44 | lz = __builtin_clzll (hx); |
45 | int shift = lz - 15; |
46 | if (shift >= 64) |
47 | { |
48 | hx = lx << (shift - 64); |
49 | lx = 0; |
50 | } |
51 | else |
52 | { |
53 | /* 2 <= SHIFT <= 63. */ |
54 | hx = (hx << shift) | (lx >> (64 - shift)); |
55 | lx <<= shift; |
56 | } |
57 | hx = (hx & 0xffffffffffffULL) | ((0x3fffULL + 127 - lz) << 48); |
58 | _Float128 ret; |
59 | SET_LDOUBLE_WORDS64 (ret, hx, lx); |
60 | return ret; |
61 | } |
62 | libm_alias_ldouble (__getpayload, getpayload) |
63 | |