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bb2376a6ed
nearbyint(), remquof(), remquo(), roundf(), round(), tgammaf(), tgamma(), truncf(), trunc(). Sort of implemented fmaf() and fma(), which really ought to be done in "SIMD" fashion. This completes the "real" floating point math library (ignoring for a moment that the floating point environment code is still not implemented). git-svn-id: file:///Users/olsen/Code/migration-svn-zu-git/logical-line-staging/clib2/trunk@15035 87f5fb63-7c3d-0410-a384-fd976d0f7a62
104 lines
3.2 KiB
C
104 lines
3.2 KiB
C
/*
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* $Id: math_roundf.c,v 1.2 2005-10-09 10:38:55 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) 2002-2005 by Olaf Barthel <olsen@sourcery.han.de>
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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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#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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float
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roundf(float x)
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{
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int signbit;
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ULONG w;
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/* Most significant word, least significant word. */
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int exponent_less_127;
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GET_FLOAT_WORD(w, x);
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/* Extract sign bit. */
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signbit = w & 0x80000000;
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/* Extract exponent field. */
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exponent_less_127 = (int)((w & 0x7f800000) >> 23) - 127;
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if (exponent_less_127 < 23)
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{
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if (exponent_less_127 < 0)
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{
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w &= 0x80000000;
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if (exponent_less_127 == -1)
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/* Result is +1.0 or -1.0. */
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w |= (127 << 23);
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}
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else
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{
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unsigned int exponent_mask = 0x007fffff >> exponent_less_127;
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if ((w & exponent_mask) == 0)
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/* x has an integral value. */
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return x;
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w += 0x00400000 >> exponent_less_127;
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w &= ~exponent_mask;
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}
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}
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else
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{
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if (exponent_less_127 == 128)
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/* x is NaN or infinite. */
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return x + x;
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else
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return x;
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}
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SET_FLOAT_WORD(x, w);
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return x;
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}
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/****************************************************************************/
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#endif /* FLOATING_POINT_SUPPORT */
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