Ryujinx/Ryujinx.Memory/Range/MultiRange.cs

349 lines
12 KiB
C#
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using System;
using System.Collections.Generic;
namespace Ryujinx.Memory.Range
{
/// <summary>
/// Sequence of physical memory regions that a single non-contiguous virtual memory region maps to.
/// </summary>
public struct MultiRange : IEquatable<MultiRange>
{
private readonly MemoryRange _singleRange;
private readonly MemoryRange[] _ranges;
private bool HasSingleRange => _ranges == null;
/// <summary>
/// Total of physical sub-ranges on the virtual memory region.
/// </summary>
public int Count => HasSingleRange ? 1 : _ranges.Length;
/// <summary>
/// Minimum start address of all sub-ranges.
/// </summary>
public ulong MinAddress { get; }
/// <summary>
/// Maximum end address of all sub-ranges.
/// </summary>
public ulong MaxAddress { get; }
/// <summary>
/// Creates a new multi-range with a single physical region.
/// </summary>
/// <param name="address">Start address of the region</param>
/// <param name="size">Size of the region in bytes</param>
public MultiRange(ulong address, ulong size)
{
_singleRange = new MemoryRange(address, size);
_ranges = null;
MinAddress = address;
MaxAddress = address + size;
}
/// <summary>
/// Creates a new multi-range with multiple physical regions.
/// </summary>
/// <param name="ranges">Array of physical regions</param>
/// <exception cref="ArgumentNullException"><paramref name="ranges"/> is null</exception>
public MultiRange(MemoryRange[] ranges)
{
_singleRange = MemoryRange.Empty;
_ranges = ranges ?? throw new ArgumentNullException(nameof(ranges));
if (ranges.Length != 0)
{
MinAddress = ulong.MaxValue;
MaxAddress = 0UL;
foreach (MemoryRange range in ranges)
{
if (MinAddress > range.Address)
{
MinAddress = range.Address;
}
if (MaxAddress < range.EndAddress)
{
MaxAddress = range.EndAddress;
}
}
}
else
{
MinAddress = 0UL;
MaxAddress = 0UL;
}
}
/// <summary>
/// Gets a slice of the multi-range.
/// </summary>
/// <param name="offset">Offset of the slice into the multi-range in bytes</param>
/// <param name="size">Size of the slice in bytes</param>
/// <returns>A new multi-range representing the given slice of this one</returns>
public MultiRange GetSlice(ulong offset, ulong size)
{
if (HasSingleRange)
{
if (_singleRange.Size - offset < size)
{
throw new ArgumentOutOfRangeException(nameof(size));
}
return new MultiRange(_singleRange.Address + offset, size);
}
else
{
var ranges = new List<MemoryRange>();
foreach (MemoryRange range in _ranges)
{
if ((long)offset <= 0)
{
ranges.Add(new MemoryRange(range.Address, Math.Min(size, range.Size)));
size -= range.Size;
}
else if (offset < range.Size)
{
ulong sliceSize = Math.Min(size, range.Size - offset);
ranges.Add(new MemoryRange(range.Address + offset, sliceSize));
size -= sliceSize;
}
if ((long)size <= 0)
{
break;
}
offset -= range.Size;
}
return new MultiRange(ranges.ToArray());
}
}
/// <summary>
/// Gets the physical region at the specified index.
/// </summary>
/// <param name="index">Index of the physical region</param>
/// <returns>Region at the index specified</returns>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="index"/> is invalid</exception>
public MemoryRange GetSubRange(int index)
{
if (HasSingleRange)
{
if (index != 0)
{
throw new ArgumentOutOfRangeException(nameof(index));
}
return _singleRange;
}
else
{
if ((uint)index >= _ranges.Length)
{
throw new ArgumentOutOfRangeException(nameof(index));
}
return _ranges[index];
}
}
/// <summary>
/// Gets the physical region at the specified index, without explicit bounds checking.
/// </summary>
/// <param name="index">Index of the physical region</param>
/// <returns>Region at the index specified</returns>
private MemoryRange GetSubRangeUnchecked(int index)
{
return HasSingleRange ? _singleRange : _ranges[index];
}
/// <summary>
/// Check if two multi-ranges overlap with each other.
/// </summary>
/// <param name="other">Other multi-range to check for overlap</param>
/// <returns>True if any sub-range overlaps, false otherwise</returns>
public bool OverlapsWith(MultiRange other)
{
if (HasSingleRange && other.HasSingleRange)
{
return _singleRange.OverlapsWith(other._singleRange);
}
else
{
for (int i = 0; i < Count; i++)
{
MemoryRange currentRange = GetSubRangeUnchecked(i);
for (int j = 0; j < other.Count; j++)
{
if (currentRange.OverlapsWith(other.GetSubRangeUnchecked(j)))
{
return true;
}
}
}
}
return false;
}
/// <summary>
/// Checks if a given multi-range is fully contained inside another.
/// </summary>
/// <param name="other">Multi-range to be checked</param>
/// <returns>True if all the sub-ranges on <paramref name="other"/> are contained inside the multi-range, with the same order, false otherwise</returns>
public bool Contains(MultiRange other)
{
return FindOffset(other) >= 0;
}
/// <summary>
/// Calculates the offset of a given multi-range inside another, when the multi-range is fully contained
/// inside the other multi-range, otherwise returns -1.
/// </summary>
/// <param name="other">Multi-range that should be fully contained inside this one</param>
/// <returns>Offset in bytes if fully contained, otherwise -1</returns>
public int FindOffset(MultiRange other)
{
int thisCount = Count;
int otherCount = other.Count;
if (thisCount == 1 && otherCount == 1)
{
MemoryRange otherFirstRange = other.GetSubRangeUnchecked(0);
MemoryRange currentFirstRange = GetSubRangeUnchecked(0);
if (otherFirstRange.Address >= currentFirstRange.Address &&
otherFirstRange.EndAddress <= currentFirstRange.EndAddress)
{
return (int)(otherFirstRange.Address - currentFirstRange.Address);
}
}
else if (thisCount >= otherCount)
{
ulong baseOffset = 0;
MemoryRange otherFirstRange = other.GetSubRangeUnchecked(0);
MemoryRange otherLastRange = other.GetSubRangeUnchecked(otherCount - 1);
for (int i = 0; i < (thisCount - otherCount) + 1; baseOffset += GetSubRangeUnchecked(i).Size, i++)
{
MemoryRange currentFirstRange = GetSubRangeUnchecked(i);
MemoryRange currentLastRange = GetSubRangeUnchecked(i + otherCount - 1);
if (otherCount > 1)
{
if (otherFirstRange.Address < currentFirstRange.Address ||
otherFirstRange.EndAddress != currentFirstRange.EndAddress)
{
continue;
}
if (otherLastRange.Address != currentLastRange.Address ||
otherLastRange.EndAddress > currentLastRange.EndAddress)
{
continue;
}
bool fullMatch = true;
for (int j = 1; j < otherCount - 1; j++)
{
if (!GetSubRangeUnchecked(i + j).Equals(other.GetSubRangeUnchecked(j)))
{
fullMatch = false;
break;
}
}
if (!fullMatch)
{
continue;
}
}
else if (currentFirstRange.Address > otherFirstRange.Address ||
currentFirstRange.EndAddress < otherFirstRange.EndAddress)
{
continue;
}
return (int)(baseOffset + (otherFirstRange.Address - currentFirstRange.Address));
}
}
return -1;
}
/// <summary>
/// Gets the total size of all sub-ranges in bytes.
/// </summary>
/// <returns>Total size in bytes</returns>
public ulong GetSize()
{
if (HasSingleRange)
{
return _singleRange.Size;
}
ulong sum = 0;
foreach (MemoryRange range in _ranges)
{
sum += range.Size;
}
return sum;
}
public override bool Equals(object obj)
{
return obj is MultiRange other && Equals(other);
}
public bool Equals(MultiRange other)
{
if (HasSingleRange && other.HasSingleRange)
{
return _singleRange.Equals(other._singleRange);
}
int thisCount = Count;
if (thisCount != other.Count)
{
return false;
}
for (int i = 0; i < thisCount; i++)
{
if (!GetSubRangeUnchecked(i).Equals(other.GetSubRangeUnchecked(i)))
{
return false;
}
}
return true;
}
public override int GetHashCode()
{
if (HasSingleRange)
{
return _singleRange.GetHashCode();
}
HashCode hash = new HashCode();
foreach (MemoryRange range in _ranges)
{
hash.Add(range);
}
return hash.ToHashCode();
}
}
}