1/* 2 * Copyright (C) 2014 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef Algorithm_h 27#define Algorithm_h 28 29#include "Algorithm.h" 30#include <algorithm> 31#include <cstdint> 32#include <cstddef> 33#include <limits> 34#include <type_traits> 35#include <chrono> 36 37namespace bmalloc { 38 39// Versions of min and max that are compatible with compile-time constants. 40template<typename T> inline constexpr T max(T a, T b) 41{ 42 return a > b ? a : b; 43} 44 45template<typename T> inline constexpr T min(T a, T b) 46{ 47 return a < b ? a : b; 48} 49 50template<typename T> inline constexpr T mask(T value, uintptr_t mask) 51{ 52 return reinterpret_cast<T>(reinterpret_cast<uintptr_t>(value) & mask); 53} 54 55template<typename T> inline constexpr bool test(T value, uintptr_t mask) 56{ 57 return !!(reinterpret_cast<uintptr_t>(value) & mask); 58} 59 60template<size_t divisor, typename T> inline constexpr T roundUpToMultipleOf(T x) 61{ 62 static_assert(divisor && !(divisor & (divisor - 1)), "'divisor' must be a power of two."); 63 return reinterpret_cast<T>((reinterpret_cast<uintptr_t>(x) + (divisor - 1ul)) & ~(divisor - 1ul)); 64} 65 66template<size_t divisor, typename T> inline constexpr T roundDownToMultipleOf(T x) 67{ 68 static_assert(divisor && !(divisor & (divisor - 1)), "'divisor' must be a power of two."); 69 return reinterpret_cast<T>(mask(reinterpret_cast<uintptr_t>(x), ~(divisor - 1ul))); 70} 71 72// Version of sizeof that returns 0 for empty classes. 73 74template<typename T> inline constexpr size_t sizeOf() 75{ 76 return std::is_empty<T>::value ? 0 : sizeof(T); 77} 78 79template<typename T> inline constexpr size_t bitCount() 80{ 81 return sizeof(T) * 8; 82} 83 84inline constexpr bool isPowerOfTwo(size_t size) 85{ 86 return !(size & (size - 1)); 87} 88 89} // namespace bmalloc 90 91#endif // Algorithm_h 92