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54 lines
1.5 KiB
C
54 lines
1.5 KiB
C
/* Copyright (C) 1996-2017 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library. If not, see
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<http://www.gnu.org/licenses/>. */
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#include <math.h>
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#ifndef FUNC
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#define FUNC frexp
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#endif
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#ifndef float_type
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#define float_type double
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#endif
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#define __CONCATX(a,b) __CONCAT(a,b)
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float_type
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__CONCATX(__,FUNC) (float_type value, int *expptr)
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{
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float_type mantissa, exponent;
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int iexponent;
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unsigned long fpsr;
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__asm ("ftst%.x %1\n"
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"fmove%.l %/fpsr, %0"
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: "=dm" (fpsr) : "f" (value));
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if (fpsr & (7 << 24))
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{
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/* Not finite or zero. */
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*expptr = 0;
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return value;
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}
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__asm ("fgetexp%.x %1, %0" : "=f" (exponent) : "f" (value));
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iexponent = (int) exponent + 1;
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*expptr = iexponent;
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__asm ("fscale%.l %2, %0"
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: "=f" (mantissa)
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: "0" (value), "dmi" (-iexponent));
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return mantissa;
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}
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weak_alias (__CONCATX(__,FUNC), FUNC)
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