44 lines
1.7 KiB
C
44 lines
1.7 KiB
C
/* Test for signaling NaN.
|
|
Copyright (C) 2013-2022 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <math.h>
|
|
#include <math_private.h>
|
|
#include <nan-high-order-bit.h>
|
|
|
|
int
|
|
__issignalingf (float x)
|
|
{
|
|
uint32_t xi;
|
|
GET_FLOAT_WORD (xi, x);
|
|
#if HIGH_ORDER_BIT_IS_SET_FOR_SNAN
|
|
/* We only have to care about the high-order bit of x's significand, because
|
|
having it set (sNaN) already makes the significand different from that
|
|
used to designate infinity. */
|
|
return (xi & 0x7fc00000) == 0x7fc00000;
|
|
#else
|
|
/* To keep the following comparison simple, toggle the quiet/signaling bit,
|
|
so that it is set for sNaNs. This is inverse to IEEE 754-2008 (as well as
|
|
common practice for IEEE 754-1985). */
|
|
xi ^= 0x00400000;
|
|
/* We have to compare for greater (instead of greater or equal), because x's
|
|
significand being all-zero designates infinity not NaN. */
|
|
return (xi & 0x7fffffff) > 0x7fc00000;
|
|
#endif
|
|
}
|
|
libm_hidden_def (__issignalingf)
|