Ryujinx/Ryujinx.Common/Memory/SpanOrArray.cs

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C#
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using System;
namespace Ryujinx.Common.Memory
{
/// <summary>
/// A struct that can represent both a Span and Array.
/// This is useful to keep the Array representation when possible to avoid copies.
/// </summary>
/// <typeparam name="T">Element Type</typeparam>
public ref struct SpanOrArray<T> where T : unmanaged
{
public readonly T[] Array;
public readonly ReadOnlySpan<T> Span;
/// <summary>
/// Create a new SpanOrArray from an array.
/// </summary>
/// <param name="array">Array to store</param>
public SpanOrArray(T[] array)
{
Array = array;
Span = ReadOnlySpan<T>.Empty;
}
/// <summary>
/// Create a new SpanOrArray from a readonly span.
/// </summary>
/// <param name="array">Span to store</param>
public SpanOrArray(ReadOnlySpan<T> span)
{
Array = null;
Span = span;
}
/// <summary>
/// Return the contained array, or convert the span if necessary.
/// </summary>
/// <returns>An array containing the data</returns>
public T[] ToArray()
{
return Array ?? Span.ToArray();
}
/// <summary>
/// Return a ReadOnlySpan from either the array or ReadOnlySpan.
/// </summary>
/// <returns>A ReadOnlySpan containing the data</returns>
public ReadOnlySpan<T> AsSpan()
{
return Array ?? Span;
}
/// <summary>
/// Cast an array to a SpanOrArray.
/// </summary>
/// <param name="array">Source array</param>
public static implicit operator SpanOrArray<T>(T[] array)
{
return new SpanOrArray<T>(array);
}
/// <summary>
/// Cast a ReadOnlySpan to a SpanOrArray.
/// </summary>
/// <param name="span">Source ReadOnlySpan</param>
public static implicit operator SpanOrArray<T>(ReadOnlySpan<T> span)
{
return new SpanOrArray<T>(span);
}
/// <summary>
/// Cast a Span to a SpanOrArray.
/// </summary>
/// <param name="span">Source Span</param>
public static implicit operator SpanOrArray<T>(Span<T> span)
{
return new SpanOrArray<T>(span);
}
/// <summary>
/// Cast a SpanOrArray to a ReadOnlySpan
/// </summary>
/// <param name="spanOrArray">Source SpanOrArray</param>
public static implicit operator ReadOnlySpan<T>(SpanOrArray<T> spanOrArray)
{
return spanOrArray.AsSpan();
}
}
}