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/* scalb(). LoongArch version.
Copyright (C) 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/>. */
#define NO_MATH_REDIRECT
#include <math.h>
#include <libm-alias-finite.h>
#include <fpu_control.h>
#include <float.h>
double
__ieee754_scalb (double x, double fn)
{
int x_cond;
int fn_cond;
asm volatile ("fclass.d \t%0, %1" : "=f" (x_cond) : "f" (x));
asm volatile ("fclass.d \t%0, %1" : "=f" (fn_cond) : "f" (fn));
if (__glibc_unlikely(( x_cond | fn_cond) & _FCLASS_NAN))
return x * fn;
else if (__glibc_unlikely(fn_cond & _FCLASS_INF))
{
if (!(fn_cond & _FCLASS_MINF))
return x * fn;
else
return x / -fn;
}
else if (__glibc_likely(-DBL_MAX < fn && fn < DBL_MAX))
{
double rint_fn, tmp;
/* rint_fn = rint(fn) */
asm volatile ("frint.d \t%0, %1" : "=f" (rint_fn) : "f" (fn));
if (rint_fn != fn )
return (x - x) / (x - x);
asm volatile ("ftintrz.l.d \t%0, %1" : "=f" (tmp) : "f" (rint_fn));
asm volatile ("fscaleb.d \t%0, %1, %2" : "=f" (x) : "f" (x), "f" (tmp));
}
else
asm volatile ("fscaleb.d \t%0, %1, %2" : "=f" (x) : "f" (x), "f" (fn));
return x;
}
libm_alias_finite (__ieee754_scalb, __scalb)
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