1/* Get NaN payload. ldbl-128 version.
2 Copyright (C) 2016-2020 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}
62libm_alias_ldouble (__getpayload, getpayload)
63