aligned_memory.h

/*
 * Copyright (C) 2018-2024 Intel Corporation
 *
 * SPDX-License-Identifier: MIT
 *
 */

#pragma once
#include "shared/source/helpers/basic_math.h"
#include "shared/source/helpers/constants.h"
#include "shared/source/helpers/debug_helpers.h"
#include "shared/source/utilities/logger.h"

#include <algorithm>
#include <functional>

#ifdef _MSC_VER
#define ALIGNAS(x) __declspec(align(x))
#else
#define ALIGNAS(x) alignas(x)
#endif

template <typename T, typename TNoRef = typename std::remove_reference<T>::type>
constexpr inline TNoRef alignUp(T before, size_t alignment) {
    if (alignment == 0) {
        return before;
    }
    OPTIONAL_UNRECOVERABLE_IF(!Math::isPow2(alignment));
    TNoRef mask = static_cast<TNoRef>(alignment - 1);
    return (before + mask) & ~mask;
}

template <typename T, typename TNoRef = typename std::remove_reference<T>::type>
constexpr inline TNoRef alignUpNonZero(T before, size_t alignment) {
    if (before == 0) {
        return alignment;
    } else {
        return alignUp(before, alignment);
    }
}

template <typename T>
constexpr inline T *alignUp(T *ptrBefore, size_t alignment) {
    return reinterpret_cast<T *>(alignUp(reinterpret_cast<uintptr_t>(ptrBefore), alignment));
}

template <typename T, typename TNoRef = typename std::remove_reference<T>::type>
constexpr inline TNoRef alignDown(T before, size_t alignment) {
    OPTIONAL_UNRECOVERABLE_IF(!Math::isPow2(alignment));
    TNoRef mask = static_cast<TNoRef>(alignment - 1);
    return before & ~mask;
}

template <typename T>
constexpr inline T *alignDown(T *ptrBefore, size_t alignment) {
    return reinterpret_cast<T *>(alignDown(reinterpret_cast<uintptr_t>(ptrBefore), alignment));
}

inline void *alignedMalloc(size_t bytes, size_t alignment) {
    DEBUG_BREAK_IF(alignment <= 0);

    if (bytes == 0) {
        bytes = sizeof(void *);
    }

    // Make sure our alignment is at least the size of a pointer
    alignment = std::max(alignment, sizeof(void *));

    // Allocate _bytes + _alignment
    size_t sizeToAlloc = bytes + alignment;
    auto pOriginalMemory = new (std::nothrow) char[sizeToAlloc];

    // Add in the alignment
    auto pAlignedMemory = reinterpret_cast<uintptr_t>(pOriginalMemory);
    if (pAlignedMemory) {
        pAlignedMemory += alignment;
        pAlignedMemory -= pAlignedMemory % alignment;

        // Store the original pointer to facilitate deallocation
        reinterpret_cast<void **>(pAlignedMemory)[-1] = pOriginalMemory;
    }

    DBG_LOG(LogAlignedAllocations, __FUNCTION__, "Pointer:", reinterpret_cast<void *>(pOriginalMemory), "size:", sizeToAlloc);
    // Return result
    return reinterpret_cast<void *>(pAlignedMemory); // NOLINT(clang-analyzer-cplusplus.NewDeleteLeaks)
}

inline void alignedFree(void *ptr) {
    if (ptr) {
        auto originalPtr = reinterpret_cast<char **>(ptr)[-1];
        DBG_LOG(LogAlignedAllocations, __FUNCTION__, "Pointer:", reinterpret_cast<void *>(originalPtr));
        delete[] originalPtr;
    }
}

inline size_t alignSizeWholePage(const void *ptr, size_t size) {
    uintptr_t startPageMisalignedAddressOffset = reinterpret_cast<uintptr_t>(ptr) & MemoryConstants::pageMask;
    size_t alignedSizeToPage = alignUp(startPageMisalignedAddressOffset + size, MemoryConstants::pageSize);
    return alignedSizeToPage;
}

template <size_t alignment, typename T>
inline constexpr bool isAligned(T val) {
    return (static_cast<size_t>(val) % alignment) == 0;
}

template <size_t alignment, typename T>
inline bool isAligned(T *ptr) {
    return ((reinterpret_cast<uintptr_t>(ptr)) % alignment) == 0;
}

template <typename T1, typename T2>
inline bool isAligned(T1 ptr, T2 alignment) {
    OPTIONAL_UNRECOVERABLE_IF(!Math::isPow2(alignment));
    return ((static_cast<size_t>(ptr)) & (static_cast<size_t>(alignment) - 1u)) == 0;
}

template <typename T>
inline bool isAligned(T *ptr) {
    // alignment requirement (returned by alignof) is always a power of 2
    return (reinterpret_cast<uintptr_t>(ptr) & (alignof(T) - 1)) == 0;
}
inline auto allocateAlignedMemory(size_t bytes, size_t alignment) {
    return std::unique_ptr<void, std::function<decltype(alignedFree)>>(alignedMalloc(bytes, alignment), alignedFree);
}