/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- * * The contents of this file are subject to the Netscape Public License * Version 1.0 (the "NPL"); you may not use this file except in * compliance with the NPL. You may obtain a copy of the NPL at * http://www.mozilla.org/NPL/ * * Software distributed under the NPL is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL * for the specific language governing rights and limitations under the * NPL. * * The Initial Developer of this code under the NPL is Netscape * Communications Corporation. Portions created by Netscape are * Copyright (C) 1998 Netscape Communications Corporation. All Rights * Reserved. */ #ifndef _FAST_BITSET_H_ #define _FAST_BITSET_H_ #include "Fundamentals.h" #include "Pool.h" // ---------------------------------------------------------------------------- // FastBitSet // // !!!! A FastBitSet cannot have a null number bits. // class FastBitSet { friend class FastBitMatrix; // The bit matrix will need to access bits & sizeInWord. private: Uint32* bits; // Array of words to store the bits. Uint32 sizeInWords; // Number of words allocated. #ifdef DEBUG_LOG Uint32 sizeInBits; // Number of bits (only used in printPretty*()). #endif /* DEBUG_LOG */ Uint32 getNumberOfWords(Uint32 numberOfBits) const {return (numberOfBits + 31) >> 5;} Uint32 getWordOffset(Uint32 bitPos) const {return bitPos >> 5;} Uint8 getBitOffset(Uint32 bitPos) const {return bitPos & 31;} FastBitSet(const FastBitSet&); // No Copy constructor. public: // This is not a valid bitset. The method sizeTo must be called before any // use of this instance. FastBitSet() : sizeInWords(0) {} // Instanciate and allocate the bits. inline FastBitSet(Pool& pool, Uint32 sizeInBits); // This FastBitSet gets its bits from memory. inline FastBitSet(Uint32* bits, Uint32 sizeInBits); // This FastBitSet copy its bits from memory.. inline FastBitSet(Pool& pool, Uint32* bits, Uint32 sizeInBits); // Resize the bitset to sizeInBits. void sizeTo(Pool& pool, Uint32 sizeInBits); // Resize the bitset and clear all the bits. inline void sizeToAndClear(Pool& pool, Uint32 sizeInBits); // Set all the bits in this bitset. inline void set(); // Set the bit at pos. inline void set(Uint32 pos) {PR_ASSERT(sizeInWords); bits[getWordOffset(pos)] |= (1<>getBitOffset(pos))&1;} // Count the number of bits at '1'. inline Uint32 countOnes(); // Count the number of bits at '0'. inline Uint32 countZeros(); // Return the '1' bit just after pos or -1 if not found. Int32 nextOne(Int32 pos) const; // Return the '1' bit just before pos or -1 if not found. Int32 previousOne(Int32 pos) const; // Return the first '1' bit in the bitset or -1 if not found. inline Int32 firstOne() const {return nextOne(-1);} // Return the last '1' bit in the bitset or -1 if not found. inline Int32 lastOne() const {return previousOne(sizeInWords << 5);} // Return the '0' bit just after pos or -1 if not found. Int32 nextZero(Int32 pos) const; // Return the '0' bit just before pos or -1 if not found. Int32 previousZero(Int32 pos) const; // Return the first '0' bit in the bitset or -1 if not found. inline Int32 firstZero() const {return nextZero(-1);} // Return the last '1' bit in the bitset or -1 if not found. inline Int32 lastZero() const {return previousZero(sizeInWords << 5);} // Return true if at the end of the BitSet. inline bool done(Int32 pos) const {return pos == -1;} // Return true if the bitset is empty. inline bool empty() {return done(firstOne());} // Arithmetic operators. FastBitSet& operator |= (const FastBitSet& x); FastBitSet& operator &= (const FastBitSet& x); FastBitSet& operator ^= (const FastBitSet& x); FastBitSet& operator -= (const FastBitSet& x); // Comparison operators. friend bool operator == (const FastBitSet& x, const FastBitSet& y); friend bool operator != (const FastBitSet& x, const FastBitSet& y) {return !(x == y);} // Copy operator. FastBitSet& operator = (const FastBitSet& x); #ifdef DEBUG_LOG // Print the bitset. void printPretty(FILE* f) const; // Print the diffs with the given bitset. void printDiff(FILE* f, const FastBitSet& x) const; // Print all the '1' bits. void printPrettyOnes(FILE* f) const; // Print all the '0' bits. void printPrettyZeros(FILE* f) const; #endif }; // ---------------------------------------------------------------------------- // Inlines. // // Set all the bits in this bitset. // inline void FastBitSet::set() { PR_ASSERT(sizeInWords); Uint32* ptr = bits; Int32 count = sizeInWords - 1; register Uint32 ones = Uint32(~0); do { ptr[count] = ones; } while(--count >= 0); } // // Clear all the bits in this bitset. // inline void FastBitSet::clear() { PR_ASSERT(sizeInWords); Uint32* ptr = bits; Int32 count = sizeInWords - 1; register Uint32 zeros = Uint32(0); do { ptr[count] = zeros; } while(--count >= 0); } // // Count the number of bits at '1'. // inline Uint32 FastBitSet::countOnes() { Uint32 counter = 0; for (Int32 i = firstOne(); !done(i); i = nextOne(i)) counter++; return counter; } // // Count the number of bits at '0'. // inline Uint32 FastBitSet::countZeros() { Uint32 counter = 0; for (Int32 i = firstZero(); !done(i); i = nextZero(i)) counter++; return counter; } inline void FastBitSet::sizeToAndClear(Pool& pool, Uint32 sizeInBits) { sizeTo(pool, sizeInBits); clear(); } inline FastBitSet::FastBitSet(Pool& pool, Uint32 sizeInBits) : sizeInWords(0) { sizeToAndClear(pool, sizeInBits); } inline FastBitSet::FastBitSet(Pool& pool, Uint32* bits, Uint32 sizeInBits) : sizeInWords(0) { sizeTo(pool, sizeInBits); PR_ASSERT(sizeInWords); Int32 count = sizeInWords - 1; Uint32* dst = bits; do { dst[count] = bits[count]; } while (--count >= 0); } inline FastBitSet::FastBitSet(Uint32* bits, Uint32 sizeInBits) : bits(bits), sizeInWords(getNumberOfWords(sizeInBits)) { #ifdef DEBUG_LOG this->sizeInBits = sizeInBits; #endif /* DEBUG_LOG */ } #endif /* _FAST_BITSET_H_ */