/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * * Copyright (C) 2014 by Michael Sevakis * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #ifndef BITARRAY_H #define BITARRAY_H /* Type-checked bit array definitions */ /* All this stuff gets optimized into very simple object code */ #define BITARRAY_WORD_BITS \ (sizeof (unsigned int) * 8) #define BITARRAY_NWORDS(bits) \ (((bits) + BITARRAY_WORD_BITS - 1) / BITARRAY_WORD_BITS) #define BITARRAY_BITWORD(bitnum) \ ((bitnum) / BITARRAY_WORD_BITS) #define BITARRAY_WORDBIT(bitnum) \ ((bitnum) % BITARRAY_WORD_BITS) #define BITARRAY_NBIT(word, bit) \ ((word)*BITARRAY_WORD_BITS + (bit)) #define BITARRAY_BITS(bits) \ (BITARRAY_NWORDS(bits)*BITARRAY_WORD_BITS) #define BITARRAY_BITN(bitnum) \ (1u << BITARRAY_WORDBIT(bitnum)) /** Iterators **/ #include "config.h" #include #include #if (defined(CPU_ARM) && ARM_ARCH >= 5) || UINT32_MAX < UINT_MAX #define __BITARRAY_CTZ(wval) __builtin_ctz(wval) #else #include "system.h" #define __BITARRAY_CTZ(wval) find_first_set_bit(wval) #endif #define __BITARRAY_POPCNT(wval) __builtin_popcount(wval) #ifndef BIT_N #define BIT_N(n) (1u << (n)) #endif /* Enumerate each word index */ #define FOR_EACH_BITARRAY_WORD_INDEX(nwords, index) \ for (unsigned int index = 0, _nwords = (nwords); \ index < _nwords; index++) /* Enumerate each word value */ #define FOR_EACH_BITARRAY_WORD(a, wval) \ FOR_EACH_BITARRAY_WORD_INDEX(ARRAYLEN((a)->words), _w) \ for (unsigned int wval = (a)->words[_w], _ = 1; _; _--) /* Enumerate the bit number of each set bit of a word in sequence */ #define FOR_EACH_BITARRAY_SET_WORD_BIT(wval, bit) \ for (unsigned int _wval = (wval), bit; \ _wval ? (((bit) = __BITARRAY_CTZ(_wval)), 1) : 0; \ _wval &= ~BIT_N(bit)) /* Enumerate the bit number of each set bit in the bit array in sequence */ #define FOR_EACH_BITARRAY_SET_BIT_ARR(nwords, words, nbit) \ FOR_EACH_BITARRAY_WORD_INDEX(nwords, _w) \ FOR_EACH_BITARRAY_SET_WORD_BIT(words[_w], _bit) \ for (unsigned int nbit = BITARRAY_NBIT(_w, _bit), _ = 1; _; _--) /* As above but takes an array type for an argument */ #define FOR_EACH_BITARRAY_SET_BIT(a, nbit) \ FOR_EACH_BITARRAY_SET_BIT_ARR(ARRAYLEN((a)->words), (a)->words, nbit) /** Base functions (called by typed functions) **/ /* Return the word associated with the bit */ static inline unsigned int __bitarray_get_word(unsigned int words[], unsigned int bitnum) { return words[BITARRAY_BITWORD(bitnum)]; } /* Set the word associated with the bit */ static inline void __bitarray_set_word(unsigned int words[], unsigned int bitnum, unsigned int wordval) { words[BITARRAY_BITWORD(bitnum)] = wordval; } /* Set the bit at index 'bitnum' to '1' */ static inline void __bitarray_set_bit(unsigned int words[], unsigned int bitnum) { unsigned int word = BITARRAY_BITWORD(bitnum); unsigned int bit = BITARRAY_BITN(bitnum); words[word] |= bit; } /* Set the bit at index 'bitnum' to '0' */ static inline void __bitarray_clear_bit(unsigned int words[], unsigned int bitnum) { unsigned int word = BITARRAY_BITWORD(bitnum); unsigned int bit = BITARRAY_BITN(bitnum); words[word] &= ~bit; } /* Return the value of the specified bit ('0' or '1') */ static inline unsigned int __bitarray_test_bit(const unsigned int words[], unsigned int bitnum) { unsigned int word = BITARRAY_BITWORD(bitnum); unsigned int nbit = BITARRAY_WORDBIT(bitnum); return (words[word] >> nbit) & 1u; } /* Check if all bits in the bit array are '0' */ static inline bool __bitarray_is_clear(const unsigned int words[], unsigned int nbits) { FOR_EACH_BITARRAY_WORD_INDEX(BITARRAY_NWORDS(nbits), word) { if (words[word] != 0) return false; } return true; } /* Set every bit in the array to '0' */ static inline void __bitarray_clear(unsigned int words[], unsigned int nbits) { FOR_EACH_BITARRAY_WORD_INDEX(BITARRAY_NWORDS(nbits), word) words[word] = 0; } /* Set every bit in the array to '1' */ static inline void __bitarray_set(unsigned int words[], unsigned int nbits) { FOR_EACH_BITARRAY_WORD_INDEX(BITARRAY_NWORDS(nbits), word) words[word] = ~0u; } /* Find the lowest-indexed '1' bit in the bit array, returning the size of the array if none are set */ static inline unsigned int __bitarray_ffs(const unsigned int words[], unsigned int nbits) { FOR_EACH_BITARRAY_SET_BIT_ARR(BITARRAY_NWORDS(nbits), words, nbit) return nbit; return BITARRAY_BITS(nbits); } /* Return the number of bits currently set to '1' in the bit array */ static inline unsigned int __bitarray_popcount(const unsigned int words[], unsigned int nbits) { unsigned int count = 0; FOR_EACH_BITARRAY_WORD_INDEX(BITARRAY_NWORDS(nbits), word) count += __BITARRAY_POPCNT(words[word]); return count; } /** * Giant macro to define all the typed functions * typename: The name of the type (e.g. myarr_t myarr;) * fnprefix: The prefix all functions get (e.g. myarr_set_bit) * nbits : The minimum number of bits the array is meant to hold * (the implementation rounds this up to the word size * and all words may be fully utilized) * * uses 'typedef' to freely change from, e.g., struct to union without * changing source code */ #define BITARRAY_TYPE_DECLARE(typename, fnprefix, nbits) \ typedef struct \ { \ unsigned int words[BITARRAY_NWORDS(nbits)]; \ } typename; \ static inline unsigned int \ fnprefix##_get_word(typename *array, unsigned int bitnum) \ { return __bitarray_get_word(array->words, bitnum); } \ static inline void \ fnprefix##_set_word(typename *array, unsigned int bitnum, \ unsigned int wordval) \ { __bitarray_set_word(array->words, bitnum, wordval); } \ static inline void \ fnprefix##_set_bit(typename *array, unsigned int bitnum) \ { __bitarray_set_bit(array->words, bitnum); } \ static inline void \ fnprefix##_clear_bit(typename *array, unsigned int bitnum) \ { __bitarray_clear_bit(array->words, bitnum); } \ static inline unsigned int \ fnprefix##_test_bit(const typename *array, unsigned int bitnum) \ { return __bitarray_test_bit(array->words, bitnum); } \ static inline bool \ fnprefix##_is_clear(const typename *array) \ { return __bitarray_is_clear(array->words, nbits); } \ static inline void \ fnprefix##_clear(typename *array) \ { __bitarray_clear(array->words, nbits); } \ static inline void \ fnprefix##_set(typename *array) \ { __bitarray_set(array->words, nbits); } \ static inline unsigned int \ fnprefix##_ffs(const typename *array) \ { return __bitarray_ffs(array->words, nbits); } \ static inline unsigned int \ fnprefix##_popcount(const typename *array) \ { return __bitarray_popcount(array->words, nbits); } #endif /* BITARRAY_H */