Merge fa5de200b3 into ef81658fbd

src/ARMeilleure/Common/AddressTable.cs

@@ -1,252 +0,0 @@
-using ARMeilleure.Diagnostics;
-using System;
-using System.Collections.Generic;
-using System.Runtime.InteropServices;
-
-namespace ARMeilleure.Common
-{
-    /// <summary>
-    /// Represents a table of guest address to a value.
-    /// </summary>
-    /// <typeparam name="TEntry">Type of the value</typeparam>
-    public unsafe class AddressTable<TEntry> : IDisposable where TEntry : unmanaged
-    {
-        /// <summary>
-        /// Represents a level in an <see cref="AddressTable{TEntry}"/>.
-        /// </summary>
-        public readonly struct Level
-        {
-            /// <summary>
-            /// Gets the index of the <see cref="Level"/> in the guest address.
-            /// </summary>
-            public int Index { get; }
-
-            /// <summary>
-            /// Gets the length of the <see cref="Level"/> in the guest address.
-            /// </summary>
-            public int Length { get; }
-
-            /// <summary>
-            /// Gets the mask which masks the bits used by the <see cref="Level"/>.
-            /// </summary>
-            public ulong Mask => ((1ul << Length) - 1) << Index;
-
-            /// <summary>
-            /// Initializes a new instance of the <see cref="Level"/> structure with the specified
-            /// <paramref name="index"/> and <paramref name="length"/>.
-            /// </summary>
-            /// <param name="index">Index of the <see cref="Level"/></param>
-            /// <param name="length">Length of the <see cref="Level"/></param>
-            public Level(int index, int length)
-            {
-                (Index, Length) = (index, length);
-            }
-
-            /// <summary>
-            /// Gets the value of the <see cref="Level"/> from the specified guest <paramref name="address"/>.
-            /// </summary>
-            /// <param name="address">Guest address</param>
-            /// <returns>Value of the <see cref="Level"/> from the specified guest <paramref name="address"/></returns>
-            public int GetValue(ulong address)
-            {
-                return (int)((address & Mask) >> Index);
-            }
-        }
-
-        private bool _disposed;
-        private TEntry** _table;
-        private readonly List<IntPtr> _pages;
-
-        /// <summary>
-        /// Gets the bits used by the <see cref="Levels"/> of the <see cref="AddressTable{TEntry}"/> instance.
-        /// </summary>
-        public ulong Mask { get; }
-
-        /// <summary>
-        /// Gets the <see cref="Level"/>s used by the <see cref="AddressTable{TEntry}"/> instance.
-        /// </summary>
-        public Level[] Levels { get; }
-
-        /// <summary>
-        /// Gets or sets the default fill value of newly created leaf pages.
-        /// </summary>
-        public TEntry Fill { get; set; }
-
-        /// <summary>
-        /// Gets the base address of the <see cref="EntryTable{TEntry}"/>.
-        /// </summary>
-        /// <exception cref="ObjectDisposedException"><see cref="EntryTable{TEntry}"/> instance was disposed</exception>
-        public IntPtr Base
-        {
-            get
-            {
-                ObjectDisposedException.ThrowIf(_disposed, this);
-
-                lock (_pages)
-                {
-                    return (IntPtr)GetRootPage();
-                }
-            }
-        }
-
-        /// <summary>
-        /// Constructs a new instance of the <see cref="AddressTable{TEntry}"/> class with the specified list of
-        /// <see cref="Level"/>.
-        /// </summary>
-        /// <exception cref="ArgumentNullException"><paramref name="levels"/> is null</exception>
-        /// <exception cref="ArgumentException">Length of <paramref name="levels"/> is less than 2</exception>
-        public AddressTable(Level[] levels)
-        {
-            ArgumentNullException.ThrowIfNull(levels);
-
-            if (levels.Length < 2)
-            {
-                throw new ArgumentException("Table must be at least 2 levels deep.", nameof(levels));
-            }
-
-            _pages = new List<IntPtr>(capacity: 16);
-
-            Levels = levels;
-            Mask = 0;
-
-            foreach (var level in Levels)
-            {
-                Mask |= level.Mask;
-            }
-        }
-
-        /// <summary>
-        /// Determines if the specified <paramref name="address"/> is in the range of the
-        /// <see cref="AddressTable{TEntry}"/>.
-        /// </summary>
-        /// <param name="address">Guest address</param>
-        /// <returns><see langword="true"/> if is valid; otherwise <see langword="false"/></returns>
-        public bool IsValid(ulong address)
-        {
-            return (address & ~Mask) == 0;
-        }
-
-        /// <summary>
-        /// Gets a reference to the value at the specified guest <paramref name="address"/>.
-        /// </summary>
-        /// <param name="address">Guest address</param>
-        /// <returns>Reference to the value at the specified guest <paramref name="address"/></returns>
-        /// <exception cref="ObjectDisposedException"><see cref="EntryTable{TEntry}"/> instance was disposed</exception>
-        /// <exception cref="ArgumentException"><paramref name="address"/> is not mapped</exception>
-        public ref TEntry GetValue(ulong address)
-        {
-            ObjectDisposedException.ThrowIf(_disposed, this);
-
-            if (!IsValid(address))
-            {
-                throw new ArgumentException($"Address 0x{address:X} is not mapped onto the table.", nameof(address));
-            }
-
-            lock (_pages)
-            {
-                return ref GetPage(address)[Levels[^1].GetValue(address)];
-            }
-        }
-
-        /// <summary>
-        /// Gets the leaf page for the specified guest <paramref name="address"/>.
-        /// </summary>
-        /// <param name="address">Guest address</param>
-        /// <returns>Leaf page for the specified guest <paramref name="address"/></returns>
-        private TEntry* GetPage(ulong address)
-        {
-            TEntry** page = GetRootPage();
-
-            for (int i = 0; i < Levels.Length - 1; i++)
-            {
-                ref Level level = ref Levels[i];
-                ref TEntry* nextPage = ref page[level.GetValue(address)];
-
-                if (nextPage == null)
-                {
-                    ref Level nextLevel = ref Levels[i + 1];
-
-                    nextPage = i == Levels.Length - 2 ?
-                        (TEntry*)Allocate(1 << nextLevel.Length, Fill, leaf: true) :
-                        (TEntry*)Allocate(1 << nextLevel.Length, IntPtr.Zero, leaf: false);
-                }
-
-                page = (TEntry**)nextPage;
-            }
-
-            return (TEntry*)page;
-        }
-
-        /// <summary>
-        /// Lazily initialize and get the root page of the <see cref="AddressTable{TEntry}"/>.
-        /// </summary>
-        /// <returns>Root page of the <see cref="AddressTable{TEntry}"/></returns>
-        private TEntry** GetRootPage()
-        {
-            if (_table == null)
-            {
-                _table = (TEntry**)Allocate(1 << Levels[0].Length, fill: IntPtr.Zero, leaf: false);
-            }
-
-            return _table;
-        }
-
-        /// <summary>
-        /// Allocates a block of memory of the specified type and length.
-        /// </summary>
-        /// <typeparam name="T">Type of elements</typeparam>
-        /// <param name="length">Number of elements</param>
-        /// <param name="fill">Fill value</param>
-        /// <param name="leaf"><see langword="true"/> if leaf; otherwise <see langword="false"/></param>
-        /// <returns>Allocated block</returns>
-        private IntPtr Allocate<T>(int length, T fill, bool leaf) where T : unmanaged
-        {
-            var size = sizeof(T) * length;
-            var page = (IntPtr)NativeAllocator.Instance.Allocate((uint)size);
-            var span = new Span<T>((void*)page, length);
-
-            span.Fill(fill);
-
-            _pages.Add(page);
-
-            TranslatorEventSource.Log.AddressTableAllocated(size, leaf);
-
-            return page;
-        }
-
-        /// <summary>
-        /// Releases all resources used by the <see cref="AddressTable{TEntry}"/> instance.
-        /// </summary>
-        public void Dispose()
-        {
-            Dispose(true);
-            GC.SuppressFinalize(this);
-        }
-
-        /// <summary>
-        /// Releases all unmanaged and optionally managed resources used by the <see cref="AddressTable{TEntry}"/>
-        /// instance.
-        /// </summary>
-        /// <param name="disposing"><see langword="true"/> to dispose managed resources also; otherwise just unmanaged resouces</param>
-        protected virtual void Dispose(bool disposing)
-        {
-            if (!_disposed)
-            {
-                foreach (var page in _pages)
-                {
-                    Marshal.FreeHGlobal(page);
-                }
-
-                _disposed = true;
-            }
-        }
-
-        /// <summary>
-        /// Frees resources used by the <see cref="AddressTable{TEntry}"/> instance.
-        /// </summary>
-        ~AddressTable()
-        {
-            Dispose(false);
-        }
-    }
-}

src/ARMeilleure/Common/AddressTableLevel.cs

@@ -0,0 +1,44 @@
+namespace ARMeilleure.Common
+{
+    /// <summary>
+    /// Represents a level in an <see cref="IAddressTable{TEntry}"/>.
+    /// </summary>
+    public readonly struct AddressTableLevel
+    {
+        /// <summary>
+        /// Gets the index of the <see cref="Level"/> in the guest address.
+        /// </summary>
+        public int Index { get; }
+
+        /// <summary>
+        /// Gets the length of the <see cref="AddressTableLevel"/> in the guest address.
+        /// </summary>
+        public int Length { get; }
+
+        /// <summary>
+        /// Gets the mask which masks the bits used by the <see cref="AddressTableLevel"/>.
+        /// </summary>
+        public ulong Mask => ((1ul << Length) - 1) << Index;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AddressTableLevel"/> structure with the specified
+        /// <paramref name="index"/> and <paramref name="length"/>.
+        /// </summary>
+        /// <param name="index">Index of the <see cref="AddressTableLevel"/></param>
+        /// <param name="length">Length of the <see cref="AddressTableLevel"/></param>
+        public AddressTableLevel(int index, int length)
+        {
+            (Index, Length) = (index, length);
+        }
+
+        /// <summary>
+        /// Gets the value of the <see cref="AddressTableLevel"/> from the specified guest <paramref name="address"/>.
+        /// </summary>
+        /// <param name="address">Guest address</param>
+        /// <returns>Value of the <see cref="AddressTableLevel"/> from the specified guest <paramref name="address"/></returns>
+        public int GetValue(ulong address)
+        {
+            return (int)((address & Mask) >> Index);
+        }
+    }
+}

src/ARMeilleure/Common/AddressTablePresets.cs

@@ -0,0 +1,51 @@
+namespace ARMeilleure.Common
+{
+    public static class AddressTablePresets
+    {
+        private static readonly AddressTableLevel[] _levels64Bit =
+            new AddressTableLevel[]
+            {
+                new(31, 17),
+                new(23,  8),
+                new(15,  8),
+                new( 7,  8),
+                new( 2,  5),
+            };
+
+        private static readonly AddressTableLevel[] _levels32Bit =
+            new AddressTableLevel[]
+            {
+                new(31, 17),
+                new(23,  8),
+                new(15,  8),
+                new( 7,  8),
+                new( 1,  6),
+            };
+
+        private static readonly AddressTableLevel[] _levels64BitSparse =
+            new AddressTableLevel[]
+            {
+                new(23, 16),
+                new( 2, 21),
+            };
+
+        private static readonly AddressTableLevel[] _levels32BitSparse =
+            new AddressTableLevel[]
+            {
+                new(22, 10),
+                new( 1, 21),
+            };
+
+        public static AddressTableLevel[] GetArmPreset(bool for64Bits, bool sparse)
+        {
+            if (sparse)
+            {
+                return for64Bits ? _levels64BitSparse : _levels32BitSparse;
+            }
+            else
+            {
+                return for64Bits ? _levels64Bit : _levels32Bit;
+            }
+        }
+    }
+}

src/ARMeilleure/Common/Allocator.cs

@@ -2,7 +2,7 @@ using System;
 
 namespace ARMeilleure.Common
 {
-    unsafe abstract class Allocator : IDisposable
+    public unsafe abstract class Allocator : IDisposable
     {
         public T* Allocate<T>(ulong count = 1) where T : unmanaged
         {

src/ARMeilleure/Common/IAddressTable.cs

@@ -0,0 +1,51 @@
+using System;
+
+namespace ARMeilleure.Common
+{
+    public interface IAddressTable<TEntry> : IDisposable where TEntry : unmanaged
+    {
+        /// <summary>
+        /// True if the address table's bottom level is sparsely mapped.
+        /// This also ensures the second bottom level is filled with a dummy page rather than 0.
+        /// </summary>
+        bool Sparse { get; }
+
+        /// <summary>
+        /// Gets the bits used by the <see cref="Levels"/> of the <see cref="IAddressTable{TEntry}"/> instance.
+        /// </summary>
+        ulong Mask { get; }
+
+        /// <summary>
+        /// Gets the <see cref="AddressTableLevel"/>s used by the <see cref="IAddressTable{TEntry}"/> instance.
+        /// </summary>
+        AddressTableLevel[] Levels { get; }
+
+        /// <summary>
+        /// Gets or sets the default fill value of newly created leaf pages.
+        /// </summary>
+        TEntry Fill { get; set; }
+
+        /// <summary>
+        /// Gets the base address of the <see cref="EntryTable{TEntry}"/>.
+        /// </summary>
+        /// <exception cref="ObjectDisposedException"><see cref="EntryTable{TEntry}"/> instance was disposed</exception>
+        IntPtr Base { get; }
+
+        /// <summary>
+        /// Determines if the specified <paramref name="address"/> is in the range of the
+        /// <see cref="IAddressTable{TEntry}"/>.
+        /// </summary>
+        /// <param name="address">Guest address</param>
+        /// <returns><see langword="true"/> if is valid; otherwise <see langword="false"/></returns>
+        bool IsValid(ulong address);
+
+        /// <summary>
+        /// Gets a reference to the value at the specified guest <paramref name="address"/>.
+        /// </summary>
+        /// <param name="address">Guest address</param>
+        /// <returns>Reference to the value at the specified guest <paramref name="address"/></returns>
+        /// <exception cref="ObjectDisposedException"><see cref="EntryTable{TEntry}"/> instance was disposed</exception>
+        /// <exception cref="ArgumentException"><paramref name="address"/> is not mapped</exception>
+        ref TEntry GetValue(ulong address);
+    }
+}

src/ARMeilleure/Common/NativeAllocator.cs

@@ -3,7 +3,7 @@ using System.Runtime.InteropServices;
 
 namespace ARMeilleure.Common
 {
-    unsafe sealed class NativeAllocator : Allocator
+    public unsafe sealed class NativeAllocator : Allocator
     {
         public static NativeAllocator Instance { get; } = new();
 

src/ARMeilleure/Instructions/InstEmitFlowHelper.cs

@@ -193,6 +193,8 @@ namespace ARMeilleure.Instructions
 
             Operand hostAddress;
 
+            var table = context.FunctionTable;
+
             // If address is mapped onto the function table, we can skip the table walk. Otherwise we fallback
             // onto the dispatch stub.
             if (guestAddress.Kind == OperandKind.Constant && context.FunctionTable.IsValid(guestAddress.Value))
@@ -203,6 +205,36 @@ namespace ARMeilleure.Instructions
 
                 hostAddress = context.Load(OperandType.I64, hostAddressAddr);
             }
+            else if (table.Sparse && table.Levels.Length == 2)
+            {
+                // Inline table lookup. Only enabled when the sparse function table is enabled with 2 levels.
+                // Deliberately attempts to avoid branches.
+
+                var level0 = table.Levels[0];
+                int clearBits0 = 64 - (level0.Index + level0.Length);
+
+                Operand index = context.ShiftLeft(
+                    context.ShiftRightUI(context.ShiftLeft(guestAddress, Const(clearBits0)), Const(clearBits0 + level0.Index)),
+                    Const(3)
+                    );
+
+                Operand tableBase = !context.HasPtc ?
+                    Const(table.Base) :
+                    Const(table.Base, Ptc.FunctionTableSymbol);
+
+                Operand page = context.Load(OperandType.I64, context.Add(tableBase, index));
+
+                // Second level
+                var level1 = table.Levels[1];
+                int clearBits1 = 64 - (level1.Index + level1.Length);
+
+                Operand index2 = context.ShiftLeft(
+                    context.ShiftRightUI(context.ShiftLeft(guestAddress, Const(clearBits1)), Const(clearBits1 + level1.Index)),
+                    Const(3)
+                    );
+
+                hostAddress = context.Load(OperandType.I64, context.Add(page, index2));
+            }
             else
             {
                 hostAddress = !context.HasPtc ?

src/ARMeilleure/Signal/NativeSignalHandlerGenerator.cs

@@ -8,7 +8,7 @@ namespace ARMeilleure.Signal
 {
     public static class NativeSignalHandlerGenerator
     {
-        public const int MaxTrackedRanges = 8;
+        public const int MaxTrackedRanges = 16;
 
         private const int StructAddressOffset = 0;
         private const int StructWriteOffset = 4;

src/ARMeilleure/Translation/ArmEmitterContext.cs

@@ -46,7 +46,7 @@ namespace ARMeilleure.Translation
         public IMemoryManager Memory { get; }
 
         public EntryTable<uint> CountTable { get; }
-        public AddressTable<ulong> FunctionTable { get; }
+        public IAddressTable<ulong> FunctionTable { get; }
         public TranslatorStubs Stubs { get; }
 
         public ulong EntryAddress { get; }
@@ -62,7 +62,7 @@ namespace ARMeilleure.Translation
         public ArmEmitterContext(
             IMemoryManager memory,
             EntryTable<uint> countTable,
-            AddressTable<ulong> funcTable,
+            IAddressTable<ulong> funcTable,
             TranslatorStubs stubs,
             ulong entryAddress,
             bool highCq,

src/ARMeilleure/Translation/PTC/Ptc.cs

@@ -29,7 +29,7 @@ namespace ARMeilleure.Translation.PTC
         private const string OuterHeaderMagicString = "PTCohd\0\0";
         private const string InnerHeaderMagicString = "PTCihd\0\0";
 
-        private const uint InternalVersion = 6950; //! To be incremented manually for each change to the ARMeilleure project.
+        private const uint InternalVersion = 6978; //! To be incremented manually for each change to the ARMeilleure project.
 
         private const string ActualDir = "0";
         private const string BackupDir = "1";
@@ -40,6 +40,7 @@ namespace ARMeilleure.Translation.PTC
         public static readonly Symbol PageTableSymbol = new(SymbolType.Special, 1);
         public static readonly Symbol CountTableSymbol = new(SymbolType.Special, 2);
         public static readonly Symbol DispatchStubSymbol = new(SymbolType.Special, 3);
+        public static readonly Symbol FunctionTableSymbol = new(SymbolType.Special, 4);
 
         private const byte FillingByte = 0x00;
         private const CompressionLevel SaveCompressionLevel = CompressionLevel.Fastest;
@@ -705,6 +706,10 @@ namespace ARMeilleure.Translation.PTC
                 {
                     imm = translator.Stubs.DispatchStub;
                 }
+                else if (symbol == FunctionTableSymbol)
+                {
+                    imm = translator.FunctionTable.Base;
+                }
 
                 if (imm == null)
                 {

src/ARMeilleure/Translation/Translator.cs

@@ -22,33 +22,13 @@ namespace ARMeilleure.Translation
 {
     public class Translator
     {
-        private static readonly AddressTable<ulong>.Level[] _levels64Bit =
-            new AddressTable<ulong>.Level[]
-            {
-                new(31, 17),
-                new(23,  8),
-                new(15,  8),
-                new( 7,  8),
-                new( 2,  5),
-            };
-
-        private static readonly AddressTable<ulong>.Level[] _levels32Bit =
-            new AddressTable<ulong>.Level[]
-            {
-                new(31, 17),
-                new(23,  8),
-                new(15,  8),
-                new( 7,  8),
-                new( 1,  6),
-            };
-
         private readonly IJitMemoryAllocator _allocator;
         private readonly ConcurrentQueue<KeyValuePair<ulong, TranslatedFunction>> _oldFuncs;
 
         private readonly Ptc _ptc;
 
         internal TranslatorCache<TranslatedFunction> Functions { get; }
-        internal AddressTable<ulong> FunctionTable { get; }
+        internal IAddressTable<ulong> FunctionTable { get; }
         internal EntryTable<uint> CountTable { get; }
         internal TranslatorStubs Stubs { get; }
         internal TranslatorQueue Queue { get; }
@@ -57,7 +37,7 @@ namespace ARMeilleure.Translation
         private Thread[] _backgroundTranslationThreads;
         private volatile int _threadCount;
 
-        public Translator(IJitMemoryAllocator allocator, IMemoryManager memory, bool for64Bits)
+        public Translator(IJitMemoryAllocator allocator, IMemoryManager memory, IAddressTable<ulong> functionTable)
         {
             _allocator = allocator;
             Memory = memory;
@@ -72,7 +52,7 @@ namespace ARMeilleure.Translation
 
             CountTable = new EntryTable<uint>();
             Functions = new TranslatorCache<TranslatedFunction>();
-            FunctionTable = new AddressTable<ulong>(for64Bits ? _levels64Bit : _levels32Bit);
+            FunctionTable = functionTable;
             Stubs = new TranslatorStubs(FunctionTable);
 
             FunctionTable.Fill = (ulong)Stubs.SlowDispatchStub;

src/ARMeilleure/Translation/TranslatorStubs.cs

@@ -19,7 +19,7 @@ namespace ARMeilleure.Translation
 
         private bool _disposed;
 
-        private readonly AddressTable<ulong> _functionTable;
+        private readonly IAddressTable<ulong> _functionTable;
         private readonly Lazy<IntPtr> _dispatchStub;
         private readonly Lazy<DispatcherFunction> _dispatchLoop;
         private readonly Lazy<WrapperFunction> _contextWrapper;
@@ -86,7 +86,7 @@ namespace ARMeilleure.Translation
         /// </summary>
         /// <param name="functionTable">Function table used to store pointers to the functions that the guest code will call</param>
         /// <exception cref="ArgumentNullException"><paramref name="translator"/> is null</exception>
-        public TranslatorStubs(AddressTable<ulong> functionTable)
+        public TranslatorStubs(IAddressTable<ulong> functionTable)
         {
             ArgumentNullException.ThrowIfNull(functionTable);
 

src/Ryujinx.Cpu/AddressTable.cs

@@ -0,0 +1,486 @@
+using ARMeilleure.Memory;
+using Ryujinx.Common;
+using Ryujinx.Cpu.Signal;
+using Ryujinx.Memory;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Threading;
+using static Ryujinx.Cpu.MemoryEhMeilleure;
+
+namespace ARMeilleure.Common
+{
+    /// <summary>
+    /// Represents a table of guest address to a value.
+    /// </summary>
+    /// <typeparam name="TEntry">Type of the value</typeparam>
+    public unsafe class AddressTable<TEntry> : IAddressTable<TEntry> where TEntry : unmanaged
+    {
+        /// <summary>
+        /// Represents a page of the address table.
+        /// </summary>
+        private readonly struct AddressTablePage
+        {
+            /// <summary>
+            /// True if the allocation belongs to a sparse block, false otherwise.
+            /// </summary>
+            public readonly bool IsSparse;
+
+            /// <summary>
+            /// Base address for the page.
+            /// </summary>
+            public readonly IntPtr Address;
+
+            public AddressTablePage(bool isSparse, IntPtr address)
+            {
+                IsSparse = isSparse;
+                Address = address;
+            }
+        }
+
+        /// <summary>
+        /// A sparsely mapped block of memory with a signal handler to map pages as they're accessed.
+        /// </summary>
+        private readonly struct TableSparseBlock : IDisposable
+        {
+            public readonly SparseMemoryBlock Block;
+            private readonly TrackingEventDelegate _trackingEvent;
+
+            public TableSparseBlock(ulong size, Action<IntPtr> ensureMapped, PageInitDelegate pageInit)
+            {
+                var block = new SparseMemoryBlock(size, pageInit, null);
+
+                _trackingEvent = (ulong address, ulong size, bool write) =>
+                {
+                    ulong pointer = (ulong)block.Block.Pointer + address;
+
+                    ensureMapped((IntPtr)pointer);
+
+                    return pointer;
+                };
+
+                bool added = NativeSignalHandler.AddTrackedRegion(
+                    (nuint)block.Block.Pointer,
+                    (nuint)(block.Block.Pointer + (IntPtr)block.Block.Size),
+                    Marshal.GetFunctionPointerForDelegate(_trackingEvent));
+
+                if (!added)
+                {
+                    throw new InvalidOperationException("Number of allowed tracked regions exceeded.");
+                }
+
+                Block = block;
+            }
+
+            public void Dispose()
+            {
+                NativeSignalHandler.RemoveTrackedRegion((nuint)Block.Block.Pointer);
+
+                Block.Dispose();
+            }
+        }
+
+        private bool _disposed;
+        private TEntry** _table;
+        private readonly List<AddressTablePage> _pages;
+        private TEntry _fill;
+
+        private readonly MemoryBlock _sparseFill;
+        private readonly SparseMemoryBlock _fillBottomLevel;
+        private readonly TEntry* _fillBottomLevelPtr;
+
+        private readonly List<TableSparseBlock> _sparseReserved;
+        private readonly ReaderWriterLockSlim _sparseLock;
+
+        private ulong _sparseBlockSize;
+        private ulong _sparseReservedOffset;
+
+        public bool Sparse { get; }
+
+        /// <inheritdoc/>
+        public ulong Mask { get; }
+
+        /// <inheritdoc/>
+        public AddressTableLevel[] Levels { get; }
+
+        /// <inheritdoc/>
+        public TEntry Fill
+        {
+            get
+            {
+                return _fill;
+            }
+            set
+            {
+                UpdateFill(value);
+            }
+        }
+
+        /// <inheritdoc/>
+        public IntPtr Base
+        {
+            get
+            {
+                ObjectDisposedException.ThrowIf(_disposed, this);
+
+                lock (_pages)
+                {
+                    return (IntPtr)GetRootPage();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Constructs a new instance of the <see cref="AddressTable{TEntry}"/> class with the specified list of
+        /// <see cref="Level"/>.
+        /// </summary>
+        /// <param name="levels">Levels for the address table</param>
+        /// <param name="sparse">True if the bottom page should be sparsely mapped</param>
+        /// <exception cref="ArgumentNullException"><paramref name="levels"/> is null</exception>
+        /// <exception cref="ArgumentException">Length of <paramref name="levels"/> is less than 2</exception>
+        public AddressTable(AddressTableLevel[] levels, bool sparse)
+        {
+            ArgumentNullException.ThrowIfNull(levels);
+
+            if (levels.Length < 2)
+            {
+                throw new ArgumentException("Table must be at least 2 levels deep.", nameof(levels));
+            }
+
+            _pages = new List<AddressTablePage>(capacity: 16);
+
+            Levels = levels;
+            Mask = 0;
+
+            foreach (var level in Levels)
+            {
+                Mask |= level.Mask;
+            }
+
+            Sparse = sparse;
+
+            if (sparse)
+            {
+                // If the address table is sparse, allocate a fill block
+
+                _sparseFill = new MemoryBlock(65536, MemoryAllocationFlags.Mirrorable);
+
+                ulong bottomLevelSize = (1ul << levels.Last().Length) * (ulong)sizeof(TEntry);
+
+                _fillBottomLevel = new SparseMemoryBlock(bottomLevelSize, null, _sparseFill);
+                _fillBottomLevelPtr = (TEntry*)_fillBottomLevel.Block.Pointer;
+
+                _sparseReserved = new List<TableSparseBlock>();
+                _sparseLock = new ReaderWriterLockSlim();
+
+                _sparseBlockSize = bottomLevelSize;
+            }
+        }
+
+        /// <summary>
+        /// Create an <see cref="AddressTable{TEntry}"/> instance for an ARM function table.
+        /// Selects the best table structure for A32/A64, taking into account the selected memory manager type.
+        /// </summary>
+        /// <param name="for64Bits">True if the guest is A64, false otherwise</param>
+        /// <param name="type">Memory manager type</param>
+        /// <returns>An <see cref="AddressTable{TEntry}"/> for ARM function lookup</returns>
+        public static AddressTable<TEntry> CreateForArm(bool for64Bits, MemoryManagerType type)
+        {
+            // Assume software memory means that we don't want to use any signal handlers.
+            bool sparse = type != MemoryManagerType.SoftwareMmu && type != MemoryManagerType.SoftwarePageTable;
+
+            return new AddressTable<TEntry>(AddressTablePresets.GetArmPreset(for64Bits, sparse), sparse);
+        }
+
+        /// <summary>
+        /// Update the fill value for the bottom level of the table.
+        /// </summary>
+        /// <param name="fillValue">New fill value</param>
+        private void UpdateFill(TEntry fillValue)
+        {
+            if (_sparseFill != null)
+            {
+                Span<byte> span = _sparseFill.GetSpan(0, (int)_sparseFill.Size);
+                MemoryMarshal.Cast<byte, TEntry>(span).Fill(fillValue);
+            }
+
+            _fill = fillValue;
+        }
+
+        /// <summary>
+        /// Signal that the given code range exists.
+        /// </summary>
+        /// <param name="address"></param>
+        /// <param name="size"></param>
+        public void SignalCodeRange(ulong address, ulong size)
+        {
+            AddressTableLevel bottom = Levels.Last();
+            ulong bottomLevelEntries = 1ul << bottom.Length;
+
+            ulong entryIndex = address >> bottom.Index;
+            ulong entries = size >> bottom.Index;
+            entries += entryIndex - BitUtils.AlignDown(entryIndex, bottomLevelEntries);
+
+            _sparseBlockSize = Math.Max(_sparseBlockSize, BitUtils.AlignUp(entries, bottomLevelEntries) * (ulong)sizeof(TEntry));
+        }
+
+        /// <inheritdoc/>
+        public bool IsValid(ulong address)
+        {
+            return (address & ~Mask) == 0;
+        }
+
+        /// <inheritdoc/>
+        public ref TEntry GetValue(ulong address)
+        {
+            ObjectDisposedException.ThrowIf(_disposed, this);
+
+            if (!IsValid(address))
+            {
+                throw new ArgumentException($"Address 0x{address:X} is not mapped onto the table.", nameof(address));
+            }
+
+            lock (_pages)
+            {
+                TEntry* page = GetPage(address);
+
+                int index = Levels[^1].GetValue(address);
+
+                EnsureMapped((IntPtr)(page + index));
+
+                return ref page[index];
+            }
+        }
+
+        /// <summary>
+        /// Gets the leaf page for the specified guest <paramref name="address"/>.
+        /// </summary>
+        /// <param name="address">Guest address</param>
+        /// <returns>Leaf page for the specified guest <paramref name="address"/></returns>
+        private TEntry* GetPage(ulong address)
+        {
+            TEntry** page = GetRootPage();
+
+            for (int i = 0; i < Levels.Length - 1; i++)
+            {
+                ref AddressTableLevel level = ref Levels[i];
+                ref TEntry* nextPage = ref page[level.GetValue(address)];
+
+                if (nextPage == null || nextPage == _fillBottomLevelPtr)
+                {
+                    ref AddressTableLevel nextLevel = ref Levels[i + 1];
+
+                    if (i == Levels.Length - 2)
+                    {
+                        nextPage = (TEntry*)Allocate(1 << nextLevel.Length, Fill, leaf: true);
+                    }
+                    else
+                    {
+                        nextPage = (TEntry*)Allocate(1 << nextLevel.Length, GetFillValue(i), leaf: false);
+                    }
+                }
+
+                page = (TEntry**)nextPage;
+            }
+
+            return (TEntry*)page;
+        }
+
+        /// <summary>
+        /// Ensure the given pointer is mapped in any overlapping sparse reservations.
+        /// </summary>
+        /// <param name="ptr">Pointer to be mapped</param>
+        private void EnsureMapped(IntPtr ptr)
+        {
+            if (Sparse)
+            {
+                // Check sparse allocations to see if the pointer is in any of them.
+                // Ensure the page is committed if there's a match.
+
+                _sparseLock.EnterReadLock();
+
+                try
+                {
+                    foreach (TableSparseBlock reserved in _sparseReserved)
+                    {
+                        SparseMemoryBlock sparse = reserved.Block;
+
+                        if (ptr >= sparse.Block.Pointer && ptr < sparse.Block.Pointer + (IntPtr)sparse.Block.Size)
+                        {
+                            sparse.EnsureMapped((ulong)(ptr - sparse.Block.Pointer));
+
+                            break;
+                        }
+                    }
+                }
+                finally
+                {
+                    _sparseLock.ExitReadLock();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Get the fill value for a non-leaf level of the table.
+        /// </summary>
+        /// <param name="level">Level to get the fill value for</param>
+        /// <returns>The fill value</returns>
+        private IntPtr GetFillValue(int level)
+        {
+            if (_fillBottomLevel != null && level == Levels.Length - 2)
+            {
+                return (IntPtr)_fillBottomLevelPtr;
+            }
+            else
+            {
+                return IntPtr.Zero;
+            }
+        }
+
+        /// <summary>
+        /// Lazily initialize and get the root page of the <see cref="AddressTable{TEntry}"/>.
+        /// </summary>
+        /// <returns>Root page of the <see cref="AddressTable{TEntry}"/></returns>
+        private TEntry** GetRootPage()
+        {
+            if (_table == null)
+            {
+                _table = (TEntry**)Allocate(1 << Levels[0].Length, GetFillValue(0), leaf: false);
+            }
+
+            return _table;
+        }
+
+        /// <summary>
+        /// Initialize a leaf page with the fill value.
+        /// </summary>
+        /// <param name="page">Page to initialize</param>
+        private void InitLeafPage(Span<byte> page)
+        {
+            MemoryMarshal.Cast<byte, TEntry>(page).Fill(_fill);
+        }
+
+        /// <summary>
+        /// Reserve a new sparse block, and add it to the list.
+        /// </summary>
+        /// <returns>The new sparse block that was added</returns>
+        private TableSparseBlock ReserveNewSparseBlock()
+        {
+            var block = new TableSparseBlock(_sparseBlockSize, EnsureMapped, InitLeafPage);
+
+            _sparseReserved.Add(block);
+            _sparseReservedOffset = 0;
+
+            return block;
+        }
+
+        /// <summary>
+        /// Allocates a block of memory of the specified type and length.
+        /// </summary>
+        /// <typeparam name="T">Type of elements</typeparam>
+        /// <param name="length">Number of elements</param>
+        /// <param name="fill">Fill value</param>
+        /// <param name="leaf"><see langword="true"/> if leaf; otherwise <see langword="false"/></param>
+        /// <returns>Allocated block</returns>
+        private IntPtr Allocate<T>(int length, T fill, bool leaf) where T : unmanaged
+        {
+            var size = sizeof(T) * length;
+
+            AddressTablePage page;
+
+            if (Sparse && leaf)
+            {
+                _sparseLock.EnterWriteLock();
+
+                SparseMemoryBlock block;
+
+                if (_sparseReserved.Count == 0)
+                {
+                    block = ReserveNewSparseBlock().Block;
+                }
+                else
+                {
+                    block = _sparseReserved.Last().Block;
+
+                    if (_sparseReservedOffset == block.Block.Size)
+                    {
+                        block = ReserveNewSparseBlock().Block;
+                    }
+                }
+
+                page = new AddressTablePage(true, block.Block.Pointer + (IntPtr)_sparseReservedOffset);
+
+                _sparseReservedOffset += (ulong)size;
+
+                _sparseLock.ExitWriteLock();
+            }
+            else
+            {
+                var address = (IntPtr)NativeAllocator.Instance.Allocate((uint)size);
+                page = new AddressTablePage(false, address);
+
+                var span = new Span<T>((void*)page.Address, length);
+                span.Fill(fill);
+            }
+
+            _pages.Add(page);
+
+            //TranslatorEventSource.Log.AddressTableAllocated(size, leaf);
+
+            return page.Address;
+        }
+
+        /// <summary>
+        /// Releases all resources used by the <see cref="AddressTable{TEntry}"/> instance.
+        /// </summary>
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        /// <summary>
+        /// Releases all unmanaged and optionally managed resources used by the <see cref="AddressTable{TEntry}"/>
+        /// instance.
+        /// </summary>
+        /// <param name="disposing"><see langword="true"/> to dispose managed resources also; otherwise just unmanaged resouces</param>
+        protected virtual void Dispose(bool disposing)
+        {
+            if (!_disposed)
+            {
+                foreach (var page in _pages)
+                {
+                    if (!page.IsSparse)
+                    {
+                        Marshal.FreeHGlobal(page.Address);
+                    }
+                }
+
+                if (Sparse)
+                {
+                    foreach (TableSparseBlock block in _sparseReserved)
+                    {
+                        block.Dispose();
+                    }
+
+                    _sparseReserved.Clear();
+
+                    _fillBottomLevel.Dispose();
+                    _sparseFill.Dispose();
+                    _sparseLock.Dispose();
+                }
+
+                _disposed = true;
+            }
+        }
+
+        /// <summary>
+        /// Frees resources used by the <see cref="AddressTable{TEntry}"/> instance.
+        /// </summary>
+        ~AddressTable()
+        {
+            Dispose(false);
+        }
+    }
+}

src/Ryujinx.Cpu/Jit/JitCpuContext.cs

@@ -1,3 +1,4 @@
+using ARMeilleure.Common;
 using ARMeilleure.Memory;
 using ARMeilleure.Translation;
 using Ryujinx.Cpu.Signal;
@@ -9,11 +10,14 @@ namespace Ryujinx.Cpu.Jit
     {
         private readonly ITickSource _tickSource;
         private readonly Translator _translator;
+        private readonly AddressTable<ulong> _functionTable;
 
         public JitCpuContext(ITickSource tickSource, IMemoryManager memory, bool for64Bit)
         {
             _tickSource = tickSource;
-            _translator = new Translator(new JitMemoryAllocator(forJit: true), memory, for64Bit);
+            _functionTable = AddressTable<ulong>.CreateForArm(for64Bit, memory.Type);
+
+            _translator = new Translator(new JitMemoryAllocator(forJit: true), memory, _functionTable);
 
             if (memory.Type.IsHostMappedOrTracked())
             {
@@ -55,6 +59,7 @@ namespace Ryujinx.Cpu.Jit
         /// <inheritdoc/>
         public void PrepareCodeRange(ulong address, ulong size)
         {
+            _functionTable.SignalCodeRange(address, size);
             _translator.PrepareCodeRange(address, size);
         }
 

src/Ryujinx.Cpu/LightningJit/Arm32/Target/Arm64/InstEmitFlow.cs

@@ -140,6 +140,9 @@ namespace Ryujinx.Cpu.LightningJit.Arm32.Target.Arm64
             bool isTail = false)
         {
             int tempRegister;
+            int tempGuestAddress = -1;
+
+            bool inlineLookup = guestAddress.Kind != OperandKind.Constant && funcTable != null && funcTable.Sparse && funcTable.Levels.Length == 2;
 
             if (guestAddress.Kind == OperandKind.Constant)
             {
@@ -153,9 +156,16 @@ namespace Ryujinx.Cpu.LightningJit.Arm32.Target.Arm64
             else
             {
                 asm.StrRiUn(guestAddress, Register(regAlloc.FixedContextRegister), NativeContextOffsets.DispatchAddressOffset);
+
+                if (inlineLookup && guestAddress.Value == 0)
+                {
+                    // X0 will be overwritten. Move the address to a temp register.
+                    tempGuestAddress = regAlloc.AllocateTempGprRegister();
+                    asm.Mov(Register(tempGuestAddress), guestAddress);
+                }
             }
 
-            tempRegister = regAlloc.FixedContextRegister == 1 ? 2 : 1;
+            tempRegister = NextFreeRegister(1, tempGuestAddress);
 
             if (!isTail)
             {
@@ -176,6 +186,45 @@ namespace Ryujinx.Cpu.LightningJit.Arm32.Target.Arm64
                 asm.Mov(rn, funcPtrLoc & ~0xfffUL);
                 asm.LdrRiUn(rn, rn, (int)(funcPtrLoc & 0xfffUL));
             }
+            else if (inlineLookup)
+            {
+                // Inline table lookup. Only enabled when the sparse function table is enabled with 2 levels.
+
+                Operand indexReg = Register(NextFreeRegister(tempRegister + 1, tempGuestAddress));
+
+                if (tempGuestAddress != -1)
+                {
+                    guestAddress = Register(tempGuestAddress);
+                }
+
+                var level0 = funcTable.Levels[0];
+                asm.Ubfx(indexReg, guestAddress, level0.Index, level0.Length);
+                asm.Lsl(indexReg, indexReg, Const(3));
+
+                ulong tableBase = (ulong)funcTable.Base;
+
+                // Index into the table.
+                asm.Mov(rn, tableBase);
+                asm.Add(rn, rn, indexReg);
+
+                // Load the page address.
+                asm.LdrRiUn(rn, rn, 0);
+
+                var level1 = funcTable.Levels[1];
+                asm.Ubfx(indexReg, guestAddress, level1.Index, level1.Length);
+                asm.Lsl(indexReg, indexReg, Const(3));
+
+                // Index into the page.
+                asm.Add(rn, rn, indexReg);
+
+                // Load the final branch address
+                asm.LdrRiUn(rn, rn, 0);
+
+                if (tempGuestAddress != -1)
+                {
+                    regAlloc.FreeTempGprRegister(tempGuestAddress);
+                }
+            }
             else
             {
                 asm.Mov(rn, (ulong)funcPtr);
@@ -252,5 +301,20 @@ namespace Ryujinx.Cpu.LightningJit.Arm32.Target.Arm64
         {
             return new Operand(register, RegisterType.Integer, type);
         }
+
+        private static Operand Const(long value, OperandType type = OperandType.I64)
+        {
+            return new Operand(type, (ulong)value);
+        }
+
+        private static int NextFreeRegister(int start, int avoid)
+        {
+            if (start == avoid)
+            {
+                start++;
+            }
+
+            return start;
+        }
     }
 }

src/Ryujinx.Cpu/LightningJit/Arm64/Target/Arm64/InstEmitSystem.cs

@@ -305,6 +305,9 @@ namespace Ryujinx.Cpu.LightningJit.Arm64.Target.Arm64
             bool isTail = false)
         {
             int tempRegister;
+            int tempGuestAddress = -1;
+
+            bool inlineLookup = guestAddress.Kind != OperandKind.Constant && funcTable != null && funcTable.Sparse && funcTable.Levels.Length == 2;
 
             if (guestAddress.Kind == OperandKind.Constant)
             {
@@ -318,9 +321,16 @@ namespace Ryujinx.Cpu.LightningJit.Arm64.Target.Arm64
             else
             {
                 asm.StrRiUn(guestAddress, Register(regAlloc.FixedContextRegister), NativeContextOffsets.DispatchAddressOffset);
+
+                if (inlineLookup && guestAddress.Value == 0)
+                {
+                    // X0 will be overwritten. Move the address to a temp register.
+                    tempGuestAddress = regAlloc.AllocateTempGprRegister();
+                    asm.Mov(Register(tempGuestAddress), guestAddress);
+                }
             }
 
-            tempRegister = regAlloc.FixedContextRegister == 1 ? 2 : 1;
+            tempRegister = NextFreeRegister(1, tempGuestAddress);
 
             if (!isTail)
             {
@@ -341,6 +351,45 @@ namespace Ryujinx.Cpu.LightningJit.Arm64.Target.Arm64
                 asm.Mov(rn, funcPtrLoc & ~0xfffUL);
                 asm.LdrRiUn(rn, rn, (int)(funcPtrLoc & 0xfffUL));
             }
+            else if (inlineLookup)
+            {
+                // Inline table lookup. Only enabled when the sparse function table is enabled with 2 levels.
+
+                Operand indexReg = Register(NextFreeRegister(tempRegister + 1, tempGuestAddress));
+
+                if (tempGuestAddress != -1)
+                {
+                    guestAddress = Register(tempGuestAddress);
+                }
+
+                var level0 = funcTable.Levels[0];
+                asm.Ubfx(indexReg, guestAddress, level0.Index, level0.Length);
+                asm.Lsl(indexReg, indexReg, Const(3));
+
+                ulong tableBase = (ulong)funcTable.Base;
+
+                // Index into the table.
+                asm.Mov(rn, tableBase);
+                asm.Add(rn, rn, indexReg);
+
+                // Load the page address.
+                asm.LdrRiUn(rn, rn, 0);
+
+                var level1 = funcTable.Levels[1];
+                asm.Ubfx(indexReg, guestAddress, level1.Index, level1.Length);
+                asm.Lsl(indexReg, indexReg, Const(3));
+
+                // Index into the page.
+                asm.Add(rn, rn, indexReg);
+
+                // Load the final branch address
+                asm.LdrRiUn(rn, rn, 0);
+
+                if (tempGuestAddress != -1)
+                {
+                    regAlloc.FreeTempGprRegister(tempGuestAddress);
+                }
+            }
             else
             {
                 asm.Mov(rn, (ulong)funcPtr);
@@ -613,5 +662,20 @@ namespace Ryujinx.Cpu.LightningJit.Arm64.Target.Arm64
         {
             return new Operand(register, RegisterType.Integer, type);
         }
+
+        private static Operand Const(long value, OperandType type = OperandType.I64)
+        {
+            return new Operand(type, (ulong)value);
+        }
+
+        private static int NextFreeRegister(int start, int avoid)
+        {
+            if (start == avoid)
+            {
+                start++;
+            }
+
+            return start;
+        }
     }
 }

src/Ryujinx.Cpu/LightningJit/LightningJitCpuContext.cs

@@ -1,3 +1,4 @@
+using ARMeilleure.Common;
 using ARMeilleure.Memory;
 using Ryujinx.Cpu.Jit;
 using Ryujinx.Cpu.LightningJit.State;
@@ -8,11 +9,15 @@ namespace Ryujinx.Cpu.LightningJit
     {
         private readonly ITickSource _tickSource;
         private readonly Translator _translator;
+        private readonly AddressTable<ulong> _functionTable;
 
         public LightningJitCpuContext(ITickSource tickSource, IMemoryManager memory, bool for64Bit)
         {
             _tickSource = tickSource;
-            _translator = new Translator(memory, for64Bit);
+            _functionTable = AddressTable<ulong>.CreateForArm(for64Bit, memory.Type);
+
+            _translator = new Translator(memory, _functionTable);
+
             memory.UnmapEvent += UnmapHandler;
         }
 
@@ -48,6 +53,7 @@ namespace Ryujinx.Cpu.LightningJit
         /// <inheritdoc/>
         public void PrepareCodeRange(ulong address, ulong size)
         {
+            _functionTable.SignalCodeRange(address, size);
         }
 
         public void Dispose()

src/Ryujinx.Cpu/LightningJit/Translator.cs

@@ -19,25 +19,6 @@ namespace Ryujinx.Cpu.LightningJit
         // Should be enabled on platforms that enforce W^X.
         private static bool IsNoWxPlatform => false;
 
-        private static readonly AddressTable<ulong>.Level[] _levels64Bit =
-            new AddressTable<ulong>.Level[]
-            {
-                new(31, 17),
-                new(23,  8),
-                new(15,  8),
-                new( 7,  8),
-                new( 2,  5),
-            };
-
-        private static readonly AddressTable<ulong>.Level[] _levels32Bit =
-            new AddressTable<ulong>.Level[]
-            {
-                new(23, 9),
-                new(15, 8),
-                new( 7, 8),
-                new( 1, 6),
-            };
-
         private readonly ConcurrentQueue<KeyValuePair<ulong, TranslatedFunction>> _oldFuncs;
         private readonly NoWxCache _noWxCache;
         private bool _disposed;
@@ -47,7 +28,7 @@ namespace Ryujinx.Cpu.LightningJit
         internal TranslatorStubs Stubs { get; }
         internal IMemoryManager Memory { get; }
 
-        public Translator(IMemoryManager memory, bool for64Bits)
+        public Translator(IMemoryManager memory, AddressTable<ulong> functionTable)
         {
             Memory = memory;
 
@@ -63,7 +44,7 @@ namespace Ryujinx.Cpu.LightningJit
             }
 
             Functions = new TranslatorCache<TranslatedFunction>();
-            FunctionTable = new AddressTable<ulong>(for64Bits ? _levels64Bit : _levels32Bit);
+            FunctionTable = functionTable;
             Stubs = new TranslatorStubs(FunctionTable, _noWxCache);
 
             FunctionTable.Fill = (ulong)Stubs.SlowDispatchStub;

src/Ryujinx.Memory/SparseMemoryBlock.cs

@@ -0,0 +1,125 @@
+using Ryujinx.Common;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+
+namespace Ryujinx.Memory
+{
+    public delegate void PageInitDelegate(Span<byte> page);
+
+    public class SparseMemoryBlock : IDisposable
+    {
+        private const ulong MapGranularity = 1UL << 17;
+
+        private readonly PageInitDelegate _pageInit;
+
+        private readonly object _lock = new object();
+        private readonly ulong _pageSize;
+        private readonly MemoryBlock _reservedBlock;
+        private readonly List<MemoryBlock> _mappedBlocks;
+        private ulong _mappedBlockUsage;
+
+        private readonly ulong[] _mappedPageBitmap;
+
+        public MemoryBlock Block => _reservedBlock;
+
+        public SparseMemoryBlock(ulong size, PageInitDelegate pageInit, MemoryBlock fill)
+        {
+            _pageSize = MemoryBlock.GetPageSize();
+            _reservedBlock = new MemoryBlock(size, MemoryAllocationFlags.Reserve | MemoryAllocationFlags.ViewCompatible);
+            _mappedBlocks = new List<MemoryBlock>();
+            _pageInit = pageInit;
+
+            int pages = (int)BitUtils.DivRoundUp(size, _pageSize);
+            int bitmapEntries = BitUtils.DivRoundUp(pages, 64);
+            _mappedPageBitmap = new ulong[bitmapEntries];
+
+            if (fill != null)
+            {
+                // Fill the block with mappings from the fill block.
+
+                if (fill.Size % _pageSize != 0)
+                {
+                    throw new ArgumentException("Fill memory block should be page aligned.", nameof(fill));
+                }
+
+                int repeats = (int)BitUtils.DivRoundUp(size, fill.Size);
+
+                ulong offset = 0;
+                for (int i = 0; i < repeats; i++)
+                {
+                    _reservedBlock.MapView(fill, 0, offset, Math.Min(fill.Size, size - offset));
+                    offset += fill.Size;
+                }
+            }
+
+            // If a fill block isn't provided, the pages that aren't EnsureMapped are unmapped.
+            // The caller can rely on signal handler to fill empty pages instead.
+        }
+
+        private void MapPage(ulong pageOffset)
+        {
+            // Take a page from the latest mapped block.
+            MemoryBlock block = _mappedBlocks.LastOrDefault();
+
+            if (block == null || _mappedBlockUsage == MapGranularity)
+            {
+                // Need to map some more memory.
+
+                block = new MemoryBlock(MapGranularity, MemoryAllocationFlags.Mirrorable);
+
+                _mappedBlocks.Add(block);
+
+                _mappedBlockUsage = 0;
+            }
+
+            _pageInit(block.GetSpan(_mappedBlockUsage, (int)_pageSize));
+            _reservedBlock.MapView(block, _mappedBlockUsage, pageOffset, _pageSize);
+
+            _mappedBlockUsage += _pageSize;
+        }
+
+        public void EnsureMapped(ulong offset)
+        {
+            int pageIndex = (int)(offset / _pageSize);
+            int bitmapIndex = pageIndex >> 6;
+
+            ref ulong entry = ref _mappedPageBitmap[bitmapIndex];
+            ulong bit = 1UL << (pageIndex & 63);
+
+            if ((Volatile.Read(ref entry) & bit) == 0)
+            {
+                // Not mapped.
+
+                lock (_lock)
+                {
+                    // Check the bit while locked to make sure that this only happens once.
+
+                    ulong lockedEntry = Volatile.Read(ref entry);
+
+                    if ((lockedEntry & bit) == 0)
+                    {
+                        MapPage(offset & ~(_pageSize - 1));
+
+                        lockedEntry |= bit;
+
+                        Interlocked.Exchange(ref entry, lockedEntry);
+                    }
+                }
+            }
+        }
+
+        public void Dispose()
+        {
+            _reservedBlock.Dispose();
+
+            foreach (MemoryBlock block in _mappedBlocks)
+            {
+                block.Dispose();
+            }
+
+            GC.SuppressFinalize(this);
+        }
+    }
+}

src/Ryujinx.Tests/Cpu/CpuContext.cs

@@ -1,3 +1,4 @@
+using ARMeilleure.Common;
 using ARMeilleure.Memory;
 using ARMeilleure.State;
 using ARMeilleure.Translation;
@@ -12,7 +13,7 @@ namespace Ryujinx.Tests.Cpu
 
         public CpuContext(IMemoryManager memory, bool for64Bit)
         {
-            _translator = new Translator(new JitMemoryAllocator(), memory, for64Bit);
+            _translator = new Translator(new JitMemoryAllocator(), memory, AddressTable<ulong>.CreateForArm(for64Bit, memory.Type));
             memory.UnmapEvent += UnmapHandler;
         }
 

src/Ryujinx.Tests/Cpu/EnvironmentTests.cs

@@ -1,3 +1,4 @@
+using ARMeilleure.Common;
 using ARMeilleure.Translation;
 using NUnit.Framework;
 using Ryujinx.Cpu.Jit;
@@ -17,7 +18,10 @@ namespace Ryujinx.Tests.Cpu
         private static void EnsureTranslator()
         {
             // Create a translator, as one is needed to register the signal handler or emit methods.
-            _translator ??= new Translator(new JitMemoryAllocator(), new MockMemoryManager(), true);
+            _translator ??= new Translator(
+                new JitMemoryAllocator(),
+                new MockMemoryManager(),
+                AddressTable<ulong>.CreateForArm(true, ARMeilleure.Memory.MemoryManagerType.SoftwarePageTable));
         }
 
         [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.NoOptimization)]

src/Ryujinx.Tests/Memory/PartialUnmaps.cs

@@ -1,3 +1,4 @@
+using ARMeilleure.Common;
 using ARMeilleure.Signal;
 using ARMeilleure.Translation;
 using NUnit.Framework;
@@ -53,7 +54,10 @@ namespace Ryujinx.Tests.Memory
         private static void EnsureTranslator()
         {
             // Create a translator, as one is needed to register the signal handler or emit methods.
-            _translator ??= new Translator(new JitMemoryAllocator(), new MockMemoryManager(), true);
+            _translator ??= new Translator(
+                new JitMemoryAllocator(),
+                new MockMemoryManager(),
+                AddressTable<ulong>.CreateForArm(true, ARMeilleure.Memory.MemoryManagerType.SoftwarePageTable));
         }
 
         [Test]