| // Copyright 2017 The Dawn Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef SRC_DAWN_COMMON_MATH_H_ |
| #define SRC_DAWN_COMMON_MATH_H_ |
| |
| #include <cstddef> |
| #include <cstdint> |
| #include <cstring> |
| |
| #include <limits> |
| #include <optional> |
| #include <type_traits> |
| |
| #include "dawn/common/Assert.h" |
| |
| namespace dawn { |
| |
| // The following are not valid for 0 |
| uint32_t ScanForward(uint32_t bits); |
| uint32_t Log2(uint32_t value); |
| uint32_t Log2(uint64_t value); |
| bool IsPowerOfTwo(uint64_t n); |
| uint64_t RoundUp(uint64_t n, uint64_t m); |
| |
| constexpr uint32_t ConstexprLog2(uint64_t v) { |
| return v <= 1 ? 0 : 1 + ConstexprLog2(v / 2); |
| } |
| |
| constexpr uint32_t ConstexprLog2Ceil(uint64_t v) { |
| return v <= 1 ? 0 : ConstexprLog2(v - 1) + 1; |
| } |
| |
| inline uint32_t Log2Ceil(uint32_t v) { |
| return v <= 1 ? 0 : Log2(v - 1) + 1; |
| } |
| |
| inline uint32_t Log2Ceil(uint64_t v) { |
| return v <= 1 ? 0 : Log2(v - 1) + 1; |
| } |
| |
| uint64_t NextPowerOfTwo(uint64_t n); |
| bool IsPtrAligned(const void* ptr, size_t alignment); |
| void* AlignVoidPtr(void* ptr, size_t alignment); |
| bool IsAligned(uint32_t value, size_t alignment); |
| |
| template <typename T> |
| T Align(T value, size_t alignment) { |
| DAWN_ASSERT(value <= std::numeric_limits<T>::max() - (alignment - 1)); |
| DAWN_ASSERT(IsPowerOfTwo(alignment)); |
| DAWN_ASSERT(alignment != 0); |
| T alignmentT = static_cast<T>(alignment); |
| return (value + (alignmentT - 1)) & ~(alignmentT - 1); |
| } |
| |
| template <typename T, size_t Alignment> |
| constexpr size_t AlignSizeof() { |
| static_assert(Alignment != 0 && (Alignment & (Alignment - 1)) == 0, |
| "Alignment must be a valid power of 2."); |
| static_assert(sizeof(T) <= std::numeric_limits<size_t>::max() - (Alignment - 1)); |
| return (sizeof(T) + (Alignment - 1)) & ~(Alignment - 1); |
| } |
| |
| // Returns an aligned size for an n-sized array of T elements. If the size would overflow, returns |
| // nullopt instead. |
| template <typename T, size_t Alignment> |
| std::optional<size_t> AlignSizeofN(uint64_t n) { |
| constexpr uint64_t kMaxCountWithoutOverflows = |
| (std::numeric_limits<size_t>::max() - Alignment + 1) / sizeof(T); |
| if (n > kMaxCountWithoutOverflows) { |
| return std::nullopt; |
| } |
| return Align(sizeof(T) * n, Alignment); |
| } |
| |
| template <typename T> |
| DAWN_FORCE_INLINE T* AlignPtr(T* ptr, size_t alignment) { |
| DAWN_ASSERT(IsPowerOfTwo(alignment)); |
| DAWN_ASSERT(alignment != 0); |
| return reinterpret_cast<T*>((reinterpret_cast<size_t>(ptr) + (alignment - 1)) & |
| ~(alignment - 1)); |
| } |
| |
| template <typename T> |
| DAWN_FORCE_INLINE const T* AlignPtr(const T* ptr, size_t alignment) { |
| DAWN_ASSERT(IsPowerOfTwo(alignment)); |
| DAWN_ASSERT(alignment != 0); |
| return reinterpret_cast<const T*>((reinterpret_cast<size_t>(ptr) + (alignment - 1)) & |
| ~(alignment - 1)); |
| } |
| |
| template <typename destType, typename sourceType> |
| destType BitCast(const sourceType& source) { |
| static_assert(sizeof(destType) == sizeof(sourceType), "BitCast: cannot lose precision."); |
| destType output; |
| std::memcpy(&output, &source, sizeof(destType)); |
| return output; |
| } |
| |
| uint16_t Float32ToFloat16(float fp32); |
| float Float16ToFloat32(uint16_t fp16); |
| bool IsFloat16NaN(uint16_t fp16); |
| |
| template <typename T> |
| T FloatToUnorm(float value) { |
| return static_cast<T>(value * static_cast<float>(std::numeric_limits<T>::max())); |
| } |
| |
| float SRGBToLinear(float srgb); |
| |
| template <typename T1, |
| typename T2, |
| typename Enable = typename std::enable_if<sizeof(T1) == sizeof(T2)>::type> |
| constexpr bool IsSubset(T1 subset, T2 set) { |
| T2 bitsAlsoInSet = subset & set; |
| return bitsAlsoInSet == subset; |
| } |
| |
| } // namespace dawn |
| |
| #endif // SRC_DAWN_COMMON_MATH_H_ |