chromium/third_party/dawn/src/dawn/common/Math.h

// Copyright 2017 The Dawn & Tint Authors
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#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"
#include "partition_alloc/pointers/raw_ptr.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) { … }

constexpr uint32_t ConstexprLog2Ceil(uint64_t v) { … }

inline uint32_t Log2Ceil(uint32_t v) { … }

inline uint32_t Log2Ceil(uint64_t v) { … }

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) { … }

template <typename T>
T AlignDown(T value, size_t alignment) { … }

template <typename T, size_t Alignment>
constexpr size_t AlignSizeof() { … }

// 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) { … }

template <typename T>
DAWN_FORCE_INLINE T* AlignPtr(T* ptr, size_t alignment) { … }

template <typename T, partition_alloc::internal::RawPtrTraits Traits>
DAWN_FORCE_INLINE T* AlignPtr(raw_ptr<T, Traits> ptr, size_t alignment) { … }

template <typename T>
DAWN_FORCE_INLINE const T* AlignPtr(const T* ptr, size_t alignment) { … }

template <typename destType, typename sourceType>
destType BitCast(const sourceType& source) { … }

uint16_t Float32ToFloat16(float fp32);
float Float16ToFloat32(uint16_t fp16);
bool IsFloat16NaN(uint16_t fp16);

template <typename T>
T FloatToUnorm(float value) { … }

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) { … }

}  // namespace dawn

#endif  // SRC_DAWN_COMMON_MATH_H_