1 | /* Get NaN payload. ldbl-128 version. |
2 | Copyright (C) 2016-2017 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 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <math.h> |
20 | #include <math_private.h> |
21 | #include <stdint.h> |
22 | |
23 | _Float128 |
24 | getpayloadl (const _Float128 *x) |
25 | { |
26 | uint64_t hx, lx; |
27 | GET_LDOUBLE_WORDS64 (hx, lx, *x); |
28 | hx &= 0x7fffffffffffULL; |
29 | /* Construct the representation of the return value directly, since |
30 | 128-bit integers may not be available. */ |
31 | int lz; |
32 | if (hx == 0) |
33 | { |
34 | if (lx == 0) |
35 | return 0.0L; |
36 | else |
37 | lz = __builtin_clzll (lx) + 64; |
38 | } |
39 | else |
40 | lz = __builtin_clzll (hx); |
41 | int shift = lz - 15; |
42 | if (shift >= 64) |
43 | { |
44 | hx = lx << (shift - 64); |
45 | lx = 0; |
46 | } |
47 | else |
48 | { |
49 | /* 2 <= SHIFT <= 63. */ |
50 | hx = (hx << shift) | (lx >> (64 - shift)); |
51 | lx <<= shift; |
52 | } |
53 | hx = (hx & 0xffffffffffffULL) | ((0x3fffULL + 127 - lz) << 48); |
54 | _Float128 ret; |
55 | SET_LDOUBLE_WORDS64 (ret, hx, lx); |
56 | return ret; |
57 | } |
58 | |