1*181254a7Smrg /* Test for signaling NaN.
2*181254a7Smrg Copyright (C) 2013-2018 Free Software Foundation, Inc.
3*181254a7Smrg This file is part of the GNU C Library.
4*181254a7Smrg
5*181254a7Smrg The GNU C Library is free software; you can redistribute it and/or
6*181254a7Smrg modify it under the terms of the GNU Lesser General Public
7*181254a7Smrg License as published by the Free Software Foundation; either
8*181254a7Smrg version 2.1 of the License, or (at your option) any later version.
9*181254a7Smrg
10*181254a7Smrg The GNU C Library is distributed in the hope that it will be useful,
11*181254a7Smrg but WITHOUT ANY WARRANTY; without even the implied warranty of
12*181254a7Smrg MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13*181254a7Smrg Lesser General Public License for more details.
14*181254a7Smrg
15*181254a7Smrg You should have received a copy of the GNU Lesser General Public
16*181254a7Smrg License along with the GNU C Library; if not, see
17*181254a7Smrg <http://www.gnu.org/licenses/>. */
18*181254a7Smrg
19*181254a7Smrg #include "quadmath-imp.h"
20*181254a7Smrg
21*181254a7Smrg int
issignalingq(__float128 x)22*181254a7Smrg issignalingq (__float128 x)
23*181254a7Smrg {
24*181254a7Smrg uint64_t hxi, lxi __attribute__ ((unused));
25*181254a7Smrg GET_FLT128_WORDS64 (hxi, lxi, x);
26*181254a7Smrg #if HIGH_ORDER_BIT_IS_SET_FOR_SNAN
27*181254a7Smrg /* We only have to care about the high-order bit of x's significand, because
28*181254a7Smrg having it set (sNaN) already makes the significand different from that
29*181254a7Smrg used to designate infinity. */
30*181254a7Smrg return ((hxi & UINT64_C (0x7fff800000000000))
31*181254a7Smrg == UINT64_C (0x7fff800000000000));
32*181254a7Smrg #else
33*181254a7Smrg /* To keep the following comparison simple, toggle the quiet/signaling bit,
34*181254a7Smrg so that it is set for sNaNs. This is inverse to IEEE 754-2008 (as well as
35*181254a7Smrg common practice for IEEE 754-1985). */
36*181254a7Smrg hxi ^= UINT64_C (0x0000800000000000);
37*181254a7Smrg /* If lxi != 0, then set any suitable bit of the significand in hxi. */
38*181254a7Smrg hxi |= (lxi | -lxi) >> 63;
39*181254a7Smrg /* We have to compare for greater (instead of greater or equal), because x's
40*181254a7Smrg significand being all-zero designates infinity not NaN. */
41*181254a7Smrg return (hxi & UINT64_C (0x7fffffffffffffff)) > UINT64_C (0x7fff800000000000);
42*181254a7Smrg #endif
43*181254a7Smrg }
44