/* libFLAC - Free Lossless Audio Codec library * Copyright (C) 2001-2009  Josh Coalson * Copyright (C) 2011-2016  Xiph.Org Foundation * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of the Xiph.org Foundation nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #ifndef FLAC__PRIVATE__BITMATH_H#define FLAC__PRIVATE__BITMATH_H #include "../FLAC/ordinals.h" #include "../share/compat.h" #if defined(_MSC_VER)#include <intrin.h> /* for _BitScanReverse* */#endif /* Will never be emitted for MSVC, GCC, Intel compilers */static inline uint32_t FLAC__clz_soft_uint32(FLAC__uint32 word){	static const uint8_t byte_to_unary_table[] = {	8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	}; 	return word > 0xffffff ? byte_to_unary_table[word >> 24] :		word > 0xffff ? byte_to_unary_table[word >> 16] + 8 :		word > 0xff ? byte_to_unary_table[word >> 8] + 16 :		byte_to_unary_table[word] + 24;} static inline uint32_t FLAC__clz_uint32(FLAC__uint32 v){/* Never used with input 0 */#if defined(__INTEL_COMPILER)	return _bit_scan_reverse(v) ^ 31U;#elif defined(__GNUC__) && (__GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4))/* This will translate either to (bsr ^ 31U), clz , ctlz, cntlz, lzcnt depending on * -march= setting or to a software routine in exotic machines. */	return __builtin_clz(v);#elif defined(_MSC_VER)	{		DWORD idx;		_BitScanReverse(&idx, v);		return (uint32_t)(idx ^ 31U);	}#else	return FLAC__clz_soft_uint32(v);#endif} /* Used when 64-bit bsr/clz is unavailable; can use 32-bit bsr/clz when possible */static inline uint32_t FLAC__clz_soft_uint64(FLAC__uint64 word){	return (FLAC__uint32)(word>>32) ? FLAC__clz_uint32((FLAC__uint32)(word>>32)) :		FLAC__clz_uint32((FLAC__uint32)word) + 32;} static inline uint32_t FLAC__clz_uint64(FLAC__uint64 v){	/* Never used with input 0 */#if defined(__GNUC__) && (__GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4))	return __builtin_clzll(v);#elif (defined(__INTEL_COMPILER) || defined(_MSC_VER)) && (defined(_M_IA64) || defined(_M_X64))	{		DWORD idx;		_BitScanReverse64(&idx, v);		return (uint32_t)(idx ^ 63U);	}#else	return FLAC__clz_soft_uint64(v);#endif} /* These two functions work with input 0 */static inline uint32_t FLAC__clz2_uint32(FLAC__uint32 v){	if (!v)		return 32;	return FLAC__clz_uint32(v);} static inline uint32_t FLAC__clz2_uint64(FLAC__uint64 v){	if (!v)		return 64;	return FLAC__clz_uint64(v);} /* An example of what FLAC__bitmath_ilog2() computes: * * ilog2( 0) = assertion failure * ilog2( 1) = 0 * ilog2( 2) = 1 * ilog2( 3) = 1 * ilog2( 4) = 2 * ilog2( 5) = 2 * ilog2( 6) = 2 * ilog2( 7) = 2 * ilog2( 8) = 3 * ilog2( 9) = 3 * ilog2(10) = 3 * ilog2(11) = 3 * ilog2(12) = 3 * ilog2(13) = 3 * ilog2(14) = 3 * ilog2(15) = 3 * ilog2(16) = 4 * ilog2(17) = 4 * ilog2(18) = 4 */ static inline uint32_t FLAC__bitmath_ilog2(FLAC__uint32 v){#if defined(__INTEL_COMPILER)	return _bit_scan_reverse(v);#elif defined(_MSC_VER)	{		DWORD idx;		_BitScanReverse(&idx, v);		return (uint32_t)idx;	}#else	return FLAC__clz_uint32(v) ^ 31U;#endif} static inline uint32_t FLAC__bitmath_ilog2_wide(FLAC__uint64 v){#if defined(__GNUC__) && (__GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4))	return __builtin_clzll(v) ^ 63U;/* Sorry, only supported in x64/Itanium.. and both have fast FPU which makes integer-only encoder pointless */#elif (defined(__INTEL_COMPILER) || defined(_MSC_VER)) && (defined(_M_IA64) || defined(_M_X64))	{		DWORD idx;		_BitScanReverse64(&idx, v);		return (uint32_t)idx;	}#else/*  Brain-damaged compilers will use the fastest possible way that is,	de Bruijn sequences (http://supertech.csail.mit.edu/papers/debruijn.pdf)	(C) Timothy B. Terriberry (tterribe@xiph.org) 2001-2009 CC0 (Public domain).*/	{		static const uint8_t DEBRUIJN_IDX64[64]={			0, 1, 2, 7, 3,13, 8,19, 4,25,14,28, 9,34,20,40,			5,17,26,38,15,46,29,48,10,31,35,54,21,50,41,57,			63, 6,12,18,24,27,33,39,16,37,45,47,30,53,49,56,			62,11,23,32,36,44,52,55,61,22,43,51,60,42,59,58		};		v|= v>>1;		v|= v>>2;		v|= v>>4;		v|= v>>8;		v|= v>>16;		v|= v>>32;		v= (v>>1)+1;		return DEBRUIJN_IDX64[v*FLAC__U64L(0x218A392CD3D5DBF)>>58&0x3F];	}#endif} uint32_t FLAC__bitmath_silog2(FLAC__int64 v); #endif