/* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
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 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
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#ifndef BitUtils_h
#define BitUtils_h

// TODO: This can be removed once <bit> works completely in Driverkit builds

#include <bit>
#include <cstdint>

namespace lsl {
inline
__attribute__ ((__const__))
uint64_t bit_ceil(uint64_t value) {
    value--;
    value |= value >> 1;
    value |= value >> 2;
    value |= value >> 4;
    value |= value >> 8;
    value |= value >> 16;
    value |= value >> 32;
    value++;
    return value;
}

inline
__attribute__ ((__const__))
uint64_t bit_width(uint64_t value) {
    return std::numeric_limits<uint64_t>::digits - std::countl_zero(value);
}

template<uint64_t SIZE>
inline
__attribute__((__const__))
uint64_t roundDownToAligned(uint64_t value) {
    static_assert(std::popcount(SIZE) == 1);
    return (value & ~(SIZE-1));
}

template<uint64_t SIZE>
inline
__attribute__((__const__))
uint64_t roundToNextAligned(uint64_t value) {
    static_assert(std::popcount(SIZE) == 1);
    return (value+(SIZE-1) & (-1*SIZE));
}

inline
uint64_t roundDownToAligned(uint64_t alignment, uint64_t value) {
    return (value & ~(alignment-1));
}

inline
uint64_t roundToNextAligned(uint64_t alignment, uint64_t value) {
    return (value+(alignment-1) & (-1*alignment));
}

};

#endif /* BitUtils_h */