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/* vim:ts=8:sts=4:sw=4:noai:noexpandtab
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* Shared math routines.
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* Copyright (c) 2006-2010 Miru Limited.
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* This 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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* This 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 this library; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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#if !defined (__PGM_IMPL_FRAMEWORK_H_INSIDE__) && !defined (PGM_COMPILATION)
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# error "Only <framework.h> can be included directly."
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#if defined(_MSC_VER) && (_MSC_VER >= 1200)
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#ifndef __PGM_IMPL_MATH_H__
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#define __PGM_IMPL_MATH_H__
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#include <pgm/types.h>
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/* fast log base 2 of power of 2
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static inline unsigned pgm_power2_log2 (unsigned) PGM_GNUC_CONST;
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static const unsigned int b[] = { 0xAAAAAAAA, 0xCCCCCCCC, 0xF0F0F0F0, 0xFF00FF00, 0xFFFF0000 };
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unsigned int r = (v & b[0]) != 0;
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#if defined(__STDC_VERSION__) && (__STDC_VERSION >= 199901L)
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for (unsigned i = 4; i > 0; i--) {
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r |= ((v & b[i]) != 0) << i;
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for (i = 4; i > 0; i--) {
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r |= ((v & b[i]) != 0) << i;
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static inline size_t pgm_nearest_power (size_t, size_t) PGM_GNUC_CONST;
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unsigned pgm_spaced_primes_closest (unsigned) PGM_GNUC_PURE;
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#endif /* __PGM_IMPL_MATH_H__ */