40 lines
761 B
C++
40 lines
761 B
C++
/*
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* Array of bits.
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*/
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#pragma once
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#include <cstdint>
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#include <cassert>
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/**
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* Array of bits. Atomic where possible.
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*/
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class BitArray {
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public:
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BitArray() : _bits(0) {}
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/** Sets or clears an individual bit. */
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void set(int index, bool value);
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/** Get the number of elements. */
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int count() const { return 8*sizeof(_bits); }
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/** Get the value of a bit. */
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bool item(int index) const;
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/** Get the index of the last set bit or -1 if none. */
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int last_set() const;
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private:
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void check(int index) const { assert(index >= 0 && index < count()); }
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uint32_t* get_base() const;
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uint32_t _bits;
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};
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inline bool BitArray::item(int index) const {
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check(index);
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return (_bits & (1 << index)) != 0;
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}
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