diff options
Diffstat (limited to 'src/common/alignment.h')
| -rw-r--r-- | src/common/alignment.h | 69 |
1 files changed, 20 insertions, 49 deletions
diff --git a/src/common/alignment.h b/src/common/alignment.h index cdd4833f8..5040043de 100644 --- a/src/common/alignment.h +++ b/src/common/alignment.h | |||
| @@ -3,41 +3,50 @@ | |||
| 3 | #pragma once | 3 | #pragma once |
| 4 | 4 | ||
| 5 | #include <cstddef> | 5 | #include <cstddef> |
| 6 | #include <memory> | 6 | #include <new> |
| 7 | #include <type_traits> | 7 | #include <type_traits> |
| 8 | 8 | ||
| 9 | namespace Common { | 9 | namespace Common { |
| 10 | 10 | ||
| 11 | template <typename T> | 11 | template <typename T> |
| 12 | constexpr T AlignUp(T value, std::size_t size) { | 12 | [[nodiscard]] constexpr T AlignUp(T value, std::size_t size) { |
| 13 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); | 13 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); |
| 14 | return static_cast<T>(value + (size - value % size) % size); | 14 | auto mod{static_cast<T>(value % size)}; |
| 15 | value -= mod; | ||
| 16 | return static_cast<T>(mod == T{0} ? value : value + size); | ||
| 15 | } | 17 | } |
| 16 | 18 | ||
| 17 | template <typename T> | 19 | template <typename T> |
| 18 | constexpr T AlignDown(T value, std::size_t size) { | 20 | [[nodiscard]] constexpr T AlignDown(T value, std::size_t size) { |
| 19 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); | 21 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); |
| 20 | return static_cast<T>(value - value % size); | 22 | return static_cast<T>(value - value % size); |
| 21 | } | 23 | } |
| 22 | 24 | ||
| 23 | template <typename T> | 25 | template <typename T> |
| 24 | constexpr T AlignBits(T value, std::size_t align) { | 26 | [[nodiscard]] constexpr T AlignBits(T value, std::size_t align) { |
| 25 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); | 27 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); |
| 26 | return static_cast<T>((value + ((1ULL << align) - 1)) >> align << align); | 28 | return static_cast<T>((value + ((1ULL << align) - 1)) >> align << align); |
| 27 | } | 29 | } |
| 28 | 30 | ||
| 29 | template <typename T> | 31 | template <typename T> |
| 30 | constexpr bool Is4KBAligned(T value) { | 32 | [[nodiscard]] constexpr bool Is4KBAligned(T value) { |
| 31 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); | 33 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); |
| 32 | return (value & 0xFFF) == 0; | 34 | return (value & 0xFFF) == 0; |
| 33 | } | 35 | } |
| 34 | 36 | ||
| 35 | template <typename T> | 37 | template <typename T> |
| 36 | constexpr bool IsWordAligned(T value) { | 38 | [[nodiscard]] constexpr bool IsWordAligned(T value) { |
| 37 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); | 39 | static_assert(std::is_unsigned_v<T>, "T must be an unsigned value."); |
| 38 | return (value & 0b11) == 0; | 40 | return (value & 0b11) == 0; |
| 39 | } | 41 | } |
| 40 | 42 | ||
| 43 | template <typename T> | ||
| 44 | [[nodiscard]] constexpr bool IsAligned(T value, std::size_t alignment) { | ||
| 45 | using U = typename std::make_unsigned<T>::type; | ||
| 46 | const U mask = static_cast<U>(alignment - 1); | ||
| 47 | return (value & mask) == 0; | ||
| 48 | } | ||
| 49 | |||
| 41 | template <typename T, std::size_t Align = 16> | 50 | template <typename T, std::size_t Align = 16> |
| 42 | class AlignmentAllocator { | 51 | class AlignmentAllocator { |
| 43 | public: | 52 | public: |
| @@ -45,66 +54,28 @@ public: | |||
| 45 | using size_type = std::size_t; | 54 | using size_type = std::size_t; |
| 46 | using difference_type = std::ptrdiff_t; | 55 | using difference_type = std::ptrdiff_t; |
| 47 | 56 | ||
| 48 | using pointer = T*; | ||
| 49 | using const_pointer = const T*; | ||
| 50 | |||
| 51 | using reference = T&; | ||
| 52 | using const_reference = const T&; | ||
| 53 | |||
| 54 | using propagate_on_container_copy_assignment = std::true_type; | 57 | using propagate_on_container_copy_assignment = std::true_type; |
| 55 | using propagate_on_container_move_assignment = std::true_type; | 58 | using propagate_on_container_move_assignment = std::true_type; |
| 56 | using propagate_on_container_swap = std::true_type; | 59 | using propagate_on_container_swap = std::true_type; |
| 57 | using is_always_equal = std::true_type; | 60 | using is_always_equal = std::true_type; |
| 58 | 61 | ||
| 59 | public: | ||
| 60 | constexpr AlignmentAllocator() noexcept = default; | 62 | constexpr AlignmentAllocator() noexcept = default; |
| 61 | 63 | ||
| 62 | template <typename T2> | 64 | template <typename T2> |
| 63 | constexpr AlignmentAllocator(const AlignmentAllocator<T2, Align>&) noexcept {} | 65 | constexpr AlignmentAllocator(const AlignmentAllocator<T2, Align>&) noexcept {} |
| 64 | 66 | ||
| 65 | pointer address(reference r) noexcept { | 67 | [[nodiscard]] T* allocate(size_type n) { |
| 66 | return std::addressof(r); | 68 | return static_cast<T*>(::operator new (n * sizeof(T), std::align_val_t{Align})); |
| 67 | } | ||
| 68 | |||
| 69 | const_pointer address(const_reference r) const noexcept { | ||
| 70 | return std::addressof(r); | ||
| 71 | } | ||
| 72 | |||
| 73 | pointer allocate(size_type n) { | ||
| 74 | return static_cast<pointer>(::operator new (n, std::align_val_t{Align})); | ||
| 75 | } | 69 | } |
| 76 | 70 | ||
| 77 | void deallocate(pointer p, size_type) { | 71 | void deallocate(T* p, size_type n) { |
| 78 | ::operator delete (p, std::align_val_t{Align}); | 72 | ::operator delete (p, n * sizeof(T), std::align_val_t{Align}); |
| 79 | } | ||
| 80 | |||
| 81 | void construct(pointer p, const value_type& wert) { | ||
| 82 | new (p) value_type(wert); | ||
| 83 | } | ||
| 84 | |||
| 85 | void destroy(pointer p) { | ||
| 86 | p->~value_type(); | ||
| 87 | } | ||
| 88 | |||
| 89 | size_type max_size() const noexcept { | ||
| 90 | return size_type(-1) / sizeof(value_type); | ||
| 91 | } | 73 | } |
| 92 | 74 | ||
| 93 | template <typename T2> | 75 | template <typename T2> |
| 94 | struct rebind { | 76 | struct rebind { |
| 95 | using other = AlignmentAllocator<T2, Align>; | 77 | using other = AlignmentAllocator<T2, Align>; |
| 96 | }; | 78 | }; |
| 97 | |||
| 98 | bool operator!=(const AlignmentAllocator<T, Align>& other) const noexcept { | ||
| 99 | return !(*this == other); | ||
| 100 | } | ||
| 101 | |||
| 102 | // Returns true if and only if storage allocated from *this | ||
| 103 | // can be deallocated from other, and vice versa. | ||
| 104 | // Always returns true for stateless allocators. | ||
| 105 | bool operator==(const AlignmentAllocator<T, Align>& other) const noexcept { | ||
| 106 | return true; | ||
| 107 | } | ||
| 108 | }; | 79 | }; |
| 109 | 80 | ||
| 110 | } // namespace Common | 81 | } // namespace Common |