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/* Implement frexp for m68k.
Copyright (C) 1996-2020 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>
FLOAT
M_DECL_FUNC (__frexp) (FLOAT value, int *expptr)
{
FLOAT mantissa, exponent;
int iexponent;
unsigned long fpsr;
__asm ("ftst%.x %1\n"
"fmove%.l %/fpsr, %0"
: "=dm" (fpsr) : "f" (value));
if (fpsr & (7 << 24))
{
/* Not finite or zero. */
*expptr = 0;
return value;
}
__asm ("fgetexp%.x %1, %0" : "=f" (exponent) : "f" (value));
iexponent = (int) exponent + 1;
*expptr = iexponent;
__asm ("fscale%.l %2, %0"
: "=f" (mantissa)
: "0" (value), "dmi" (-iexponent));
return mantissa;
}
declare_mgen_alias (__frexp, frexp)
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