mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-27 21:20:18 +00:00
55 lines
1.8 KiB
C
55 lines
1.8 KiB
C
/* Set NaN payload. flt-32 version.
|
|
Copyright (C) 2016-2020 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 <libm-alias-float.h>
|
|
#include <nan-high-order-bit.h>
|
|
#include <stdint.h>
|
|
|
|
#define SET_HIGH_BIT (HIGH_ORDER_BIT_IS_SET_FOR_SNAN ? SIG : !SIG)
|
|
#define BIAS 0x7f
|
|
#define PAYLOAD_DIG 22
|
|
#define EXPLICIT_MANT_DIG 23
|
|
|
|
int
|
|
FUNC (float *x, float payload)
|
|
{
|
|
uint32_t ix;
|
|
GET_FLOAT_WORD (ix, payload);
|
|
int exponent = ix >> EXPLICIT_MANT_DIG;
|
|
/* Test if argument is (a) negative or too large; (b) too small,
|
|
except for 0 when allowed; (c) not an integer. */
|
|
if (exponent >= BIAS + PAYLOAD_DIG
|
|
|| (exponent < BIAS && !(SET_HIGH_BIT && ix == 0))
|
|
|| (ix & ((1U << (BIAS + EXPLICIT_MANT_DIG - exponent)) - 1)) != 0)
|
|
{
|
|
SET_FLOAT_WORD (*x, 0);
|
|
return 1;
|
|
}
|
|
if (ix != 0)
|
|
{
|
|
ix &= (1U << EXPLICIT_MANT_DIG) - 1;
|
|
ix |= 1U << EXPLICIT_MANT_DIG;
|
|
ix >>= BIAS + EXPLICIT_MANT_DIG - exponent;
|
|
}
|
|
ix |= 0x7f800000 | (SET_HIGH_BIT ? 0x400000 : 0);
|
|
SET_FLOAT_WORD (*x, ix);
|
|
return 0;
|
|
}
|