Redcraft/Redcraft.Utility/Source/Public/Memory/Alignment.h

#pragma once

#include "CoreTypes.h"
#include "TypeTraits/TypeTraits.h"
#include "Miscellaneous/AssertionMacros.h"

NAMESPACE_REDCRAFT_BEGIN
NAMESPACE_MODULE_BEGIN(Redcraft)
NAMESPACE_MODULE_BEGIN(Utility)

NAMESPACE_BEGIN(Memory)

/** Check if an alignment is an integer power of 2. */
FORCEINLINE constexpr bool IsValidAlignment(size_t Alignment) { return !(Alignment & (Alignment - 1)); }

/**
 * Aligns a value to the nearest higher multiple of 'Alignment', which must be a power of 2.
 *
 * @param  InValue   - The value to align.
 * @param  Alignment - The alignment value, must be a power of 2.
 *
 * @return The value aligned up to the specified alignment.
 */
template <typename T> requires (CIntegral<T> || CPointer<T>)
FORCEINLINE constexpr T Align(T InValue, size_t Alignment)
{
	checkf(IsValidAlignment(Alignment), TEXT("The alignment value must be an integer power of 2."));
	return (T)(((uint64)(InValue) + static_cast<uint64>(Alignment) - 1) & ~(static_cast<uint64>(Alignment) - 1));
}

/**
 * Aligns a value to the nearest lower multiple of 'Alignment', which must be a power of 2.
 *
 * @param  InValue   - The value to align.
 * @param  Alignment - The alignment value, must be a power of 2.
 *
 * @return The value aligned down to the specified alignment.
 */
template <typename T> requires (CIntegral<T> || CPointer<T>)
FORCEINLINE constexpr T AlignDown(T InValue, size_t Alignment)
{
	checkf(IsValidAlignment(Alignment), TEXT("The alignment value must be an integer power of 2."));
	return (T)((uint64)(InValue) & ~(static_cast<uint64>(Alignment) - 1));
}

/**
 * Aligns a value to the nearest higher multiple of 'Alignment'.
 *
 * @param  InValue   - The value to align.
 * @param  Alignment - The alignment value, can be any arbitrary value.
 *
 * @return The value aligned up to the specified alignment.
 */
template <typename T> requires (CIntegral<T> || CPointer<T>)
FORCEINLINE constexpr T AlignArbitrary(T InValue, size_t Alignment)
{
	return (T)((((uint64)(InValue) + static_cast<uint64>(Alignment) - 1) / static_cast<uint64>(Alignment)) * static_cast<uint64>(Alignment));
}

/**
 * Checks if a pointer is aligned to the specified alignment.
 *
 * @param  InValue   - The value to align.
 * @param  Alignment - The alignment value, must be a power of 2.
 *
 * @return true if the pointer is aligned to the specified alignment, false otherwise.
 */
template <typename T> requires (CIntegral<T> || CPointer<T>)
FORCEINLINE constexpr bool IsAligned(T InValue, size_t Alignment)
{
	checkf(IsValidAlignment(Alignment), TEXT("The alignment value must be an integer power of 2."));
	return !((uint64)(InValue) & (static_cast<uint64>(Alignment) - 1));
}

NAMESPACE_END(Memory)

NAMESPACE_MODULE_END(Utility)
NAMESPACE_MODULE_END(Redcraft)
NAMESPACE_REDCRAFT_END