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- Replaced ISO Latin 1 code #160 with a plain blank space (ASCII code #32) where necessary git-svn-id: file:///Users/olsen/Code/migration-svn-zu-git/logical-line-staging/clib2/trunk@15305 87f5fb63-7c3d-0410-a384-fd976d0f7a62
99 lines
3.4 KiB
C
99 lines
3.4 KiB
C
/*
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* $Id: math_scalbnf.c,v 1.3 2006-01-08 12:04:24 obarthel Exp $
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*
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* :ts=4
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*
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* Portable ISO 'C' (1994) runtime library for the Amiga computer
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* Copyright (c) 2002-2015 by Olaf Barthel <obarthel (at) gmx.net>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* - Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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*
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* - Neither the name of Olaf Barthel nor the names of contributors
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* may be used to endorse or promote products derived from this
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* software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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*
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* PowerPC math library based in part on work by Sun Microsystems
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunPro, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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*
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*
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* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
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*/
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#ifndef _MATH_HEADERS_H
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#include "math_headers.h"
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#endif /* _MATH_HEADERS_H */
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/****************************************************************************/
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#if defined(FLOATING_POINT_SUPPORT)
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/****************************************************************************/
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#if INT_MAX > 50000
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#define OVERFLOW_INT 50000
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#else
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#define OVERFLOW_INT 30000
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#endif
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static const float
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two25 = 3.355443200e+07, /* 0x4c000000 */
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twom25 = 2.9802322388e-08, /* 0x33000000 */
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huge = 1.0e+30,
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tiny = 1.0e-30;
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float
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scalbnf (float x, int n)
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{
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LONG k,ix;
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GET_FLOAT_WORD(ix,x);
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k = (ix&0x7f800000)>>23; /* extract exponent */
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if (k==0) { /* 0 or subnormal x */
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if ((ix&0x7fffffff)==0) return x; /* +-0 */
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x *= two25;
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GET_FLOAT_WORD(ix,x);
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k = ((ix&0x7f800000)>>23) - 25;
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if (n< -50000) return tiny*x; /*underflow*/
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}
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if (k==0xff) return x+x; /* NaN or Inf */
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k = k+n;
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if (k > 0xfe) return copysignf(__inff(),x); /* overflow */
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if (k > 0) /* normal result */
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{SET_FLOAT_WORD(x,(ix&0x807fffffU)|(k<<23)); return x;}
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if (k <= -25) {
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if (n > OVERFLOW_INT) /* in case integer overflow in n+k */
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return copysignf(__inff(),x);/*overflow*/
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else return tiny*copysignf(tiny,x); /*underflow*/
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}
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k += 25; /* subnormal result */
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SET_FLOAT_WORD(x,(ix&0x807fffffU)|(k<<23));
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return x*twom25;
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}
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/****************************************************************************/
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#endif /* FLOATING_POINT_SUPPORT */
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