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/*
* Copyright (c) 2005-2020 Rich Felker, et al.
*
* SPDX-License-Identifier: MIT
*
* Please see https://git.musl-libc.org/cgit/musl/tree/COPYRIGHT
* for all contributors to musl.
*/
#include <math.h>
#include <float.h>
#include "math_private.h"
#include "fpmath.h"
/*
* scalbnl (long double x, int n)
* scalbnl(x,n) returns x* 2**n computed by exponent
* manipulation rather than by actually performing an
* exponentiation or a multiplication.
*/
#if (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
long double scalbnl(long double x, int n)
{
union IEEEl2bits u;
if (n > 16383) {
x *= 0x1p16383L;
n -= 16383;
if (n > 16383) {
x *= 0x1p16383L;
n -= 16383;
if (n > 16383)
n = 16383;
}
} else if (n < -16382) {
x *= 0x1p-16382L * 0x1p113L;
n += 16382 - 113;
if (n < -16382) {
x *= 0x1p-16382L * 0x1p113L;
n += 16382 - 113;
if (n < -16382)
n = -16382;
}
}
u.e = 1.0;
u.xbits.expsign = 0x3fff + n;
return x * u.e;
}
__strong_reference(scalbnl, ldexpl);
#endif
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