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/* Set NaN payload. dbl-64 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-double.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 0x3ff
#define PAYLOAD_DIG 51
#define EXPLICIT_MANT_DIG 52
int
FUNC (double *x, double payload)
{
uint32_t hx, lx;
EXTRACT_WORDS (hx, lx, payload);
int exponent = hx >> (EXPLICIT_MANT_DIG - 32);
/* 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 && hx == 0 && lx == 0)))
{
INSERT_WORDS (*x, 0, 0);
return 1;
}
int shift = BIAS + EXPLICIT_MANT_DIG - exponent;
if (shift < 32
? (lx & ((1U << shift) - 1)) != 0
: (lx != 0 || (hx & ((1U << (shift - 32)) - 1)) != 0))
{
INSERT_WORDS (*x, 0, 0);
return 1;
}
if (exponent != 0)
{
hx &= (1U << (EXPLICIT_MANT_DIG - 32)) - 1;
hx |= 1U << (EXPLICIT_MANT_DIG - 32);
if (shift >= 32)
{
lx = hx >> (shift - 32);
hx = 0;
}
else if (shift != 0)
{
lx = (lx >> shift) | (hx << (32 - shift));
hx >>= shift;
}
}
hx |= 0x7ff00000 | (SET_HIGH_BIT ? 0x80000 : 0);
INSERT_WORDS (*x, hx, lx);
return 0;
}
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