Implement JIT Arm64 backend (#4114)

* Implement JIT Arm64 backend

* PPTC version bump

* Address some feedback from Arm64 JIT PR

* Address even more PR feedback

* Remove unused IsPageAligned function

* Sync Qc flag before calls

* Fix comment and remove unused enum

* Address riperiperi PR feedback

* Delete Breakpoint IR instruction that was only implemented for Arm64

5 files changed, 77 insertions, 59 deletions

diff --git a/Ryujinx.Memory/MemoryAllocationFlags.cs b/Ryujinx.Memory/MemoryAllocationFlags.cs
index 313f33e5..6f0ef1aa 100644
--- a/Ryujinx.Memory/MemoryAllocationFlags.cs
+++ b/Ryujinx.Memory/MemoryAllocationFlags.cs
@@ -35,6 +35,18 @@ namespace Ryujinx.Memory
         /// Indicates that the memory block should support mapping views of a mirrorable memory block.
         /// The block that is to have their views mapped should be created with the <see cref="Mirrorable"/> flag.
         /// </summary>
-        ViewCompatible = 1 << 3
+        ViewCompatible = 1 << 3,
+
+        /// <summary>
+        /// If used with the <see cref="Mirrorable"/> flag, indicates that the memory block will only be used as
+        /// backing storage and will never be accessed directly, so the memory for the block will not be mapped.
+        /// </summary>
+        NoMap = 1 << 4,
+
+        /// <summary>
+        /// Indicates that the memory will be used to store JIT generated code.
+        /// On some platforms, this requires special flags to be passed that will allow the memory to be executable.
+        /// </summary>
+        Jit = 1 << 5
     }
 }
diff --git a/Ryujinx.Memory/MemoryBlock.cs b/Ryujinx.Memory/MemoryBlock.cs
index 6b9d852d..e1f19c27 100644
--- a/Ryujinx.Memory/MemoryBlock.cs
+++ b/Ryujinx.Memory/MemoryBlock.cs
@@ -1,6 +1,6 @@
 using System;
-using System.Collections.Concurrent;
 using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
 using System.Threading;
 
 namespace Ryujinx.Memory
@@ -13,10 +13,9 @@ namespace Ryujinx.Memory
         private readonly bool _usesSharedMemory;
         private readonly bool _isMirror;
         private readonly bool _viewCompatible;
+        private readonly bool _forJit;
         private IntPtr _sharedMemory;
         private IntPtr _pointer;
-        private ConcurrentDictionary<MemoryBlock, byte> _viewStorages;
-        private int _viewCount;
 
         /// <summary>
         /// Pointer to the memory block data.
@@ -40,24 +39,27 @@ namespace Ryujinx.Memory
             if (flags.HasFlag(MemoryAllocationFlags.Mirrorable))
             {
                 _sharedMemory = MemoryManagement.CreateSharedMemory(size, flags.HasFlag(MemoryAllocationFlags.Reserve));
-                _pointer = MemoryManagement.MapSharedMemory(_sharedMemory, size);
+
+                if (!flags.HasFlag(MemoryAllocationFlags.NoMap))
+                {
+                    _pointer = MemoryManagement.MapSharedMemory(_sharedMemory, size);
+                }
+
                 _usesSharedMemory = true;
             }
             else if (flags.HasFlag(MemoryAllocationFlags.Reserve))
             {
                 _viewCompatible = flags.HasFlag(MemoryAllocationFlags.ViewCompatible);
-                _pointer = MemoryManagement.Reserve(size, _viewCompatible);
+                _forJit = flags.HasFlag(MemoryAllocationFlags.Jit);
+                _pointer = MemoryManagement.Reserve(size, _forJit, _viewCompatible);
             }
             else
             {
-                _pointer = MemoryManagement.Allocate(size);
+                _forJit = flags.HasFlag(MemoryAllocationFlags.Jit);
+                _pointer = MemoryManagement.Allocate(size, _forJit);
             }
 
             Size = size;
-
-            _viewStorages = new ConcurrentDictionary<MemoryBlock, byte>();
-            _viewStorages.TryAdd(this, 0);
-            _viewCount = 1;
         }
 
         /// <summary>
@@ -104,7 +106,7 @@ namespace Ryujinx.Memory
         /// <exception cref="InvalidMemoryRegionException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
         public bool Commit(ulong offset, ulong size)
         {
-            return MemoryManagement.Commit(GetPointerInternal(offset, size), size);
+            return MemoryManagement.Commit(GetPointerInternal(offset, size), size, _forJit);
         }
 
         /// <summary>
@@ -138,11 +140,6 @@ namespace Ryujinx.Memory
                 throw new ArgumentException("The source memory block is not mirrorable, and thus cannot be mapped on the current block.");
             }
 
-            if (_viewStorages.TryAdd(srcBlock, 0))
-            {
-                srcBlock.IncrementViewCount();
-            }
-
             MemoryManagement.MapView(srcBlock._sharedMemory, srcOffset, GetPointerInternal(dstOffset, size), size, this);
         }
 
@@ -403,33 +400,16 @@ namespace Ryujinx.Memory
                 {
                     MemoryManagement.Free(ptr, Size);
                 }
-
-                foreach (MemoryBlock viewStorage in _viewStorages.Keys)
-                {
-                    viewStorage.DecrementViewCount();
-                }
-
-                _viewStorages.Clear();
             }
-        }
-
-        /// <summary>
-        /// Increments the number of views that uses this memory block as storage.
-        /// </summary>
-        private void IncrementViewCount()
-        {
-            Interlocked.Increment(ref _viewCount);
-        }
 
-        /// <summary>
-        /// Decrements the number of views that uses this memory block as storage.
-        /// </summary>
-        private void DecrementViewCount()
-        {
-            if (Interlocked.Decrement(ref _viewCount) == 0 && _sharedMemory != IntPtr.Zero && !_isMirror)
+            if (!_isMirror)
             {
-                MemoryManagement.DestroySharedMemory(_sharedMemory);
-                _sharedMemory = IntPtr.Zero;
+                IntPtr sharedMemory = Interlocked.Exchange(ref _sharedMemory, IntPtr.Zero);
+
+                if (sharedMemory != IntPtr.Zero)
+                {
+                    MemoryManagement.DestroySharedMemory(sharedMemory);
+                }
             }
         }
 
@@ -453,6 +433,16 @@ namespace Ryujinx.Memory
             return true;
         }
 
+        public static ulong GetPageSize()
+        {
+            if (OperatingSystem.IsMacOS() && RuntimeInformation.ProcessArchitecture == Architecture.Arm64)
+            {
+                return 1UL << 14;
+            }
+
+            return 1UL << 12;
+        }
+
         private static void ThrowInvalidMemoryRegionException() => throw new InvalidMemoryRegionException();
     }
 }
diff --git a/Ryujinx.Memory/MemoryManagement.cs b/Ryujinx.Memory/MemoryManagement.cs
index 7c042eba..c4b5ac4c 100644
--- a/Ryujinx.Memory/MemoryManagement.cs
+++ b/Ryujinx.Memory/MemoryManagement.cs
@@ -4,7 +4,7 @@ namespace Ryujinx.Memory
 {
     public static class MemoryManagement
     {
-        public static IntPtr Allocate(ulong size)
+        public static IntPtr Allocate(ulong size, bool forJit)
         {
             if (OperatingSystem.IsWindows())
             {
@@ -12,7 +12,7 @@ namespace Ryujinx.Memory
             }
             else if (OperatingSystem.IsLinux() || OperatingSystem.IsMacOS())
             {
-                return MemoryManagementUnix.Allocate(size);
+                return MemoryManagementUnix.Allocate(size, forJit);
             }
             else
             {
@@ -20,7 +20,7 @@ namespace Ryujinx.Memory
             }
         }
 
-        public static IntPtr Reserve(ulong size, bool viewCompatible)
+        public static IntPtr Reserve(ulong size, bool forJit, bool viewCompatible)
         {
             if (OperatingSystem.IsWindows())
             {
@@ -28,7 +28,7 @@ namespace Ryujinx.Memory
             }
             else if (OperatingSystem.IsLinux() || OperatingSystem.IsMacOS())
             {
-                return MemoryManagementUnix.Reserve(size);
+                return MemoryManagementUnix.Reserve(size, forJit);
             }
             else
             {
@@ -36,7 +36,7 @@ namespace Ryujinx.Memory
             }
         }
 
-        public static bool Commit(IntPtr address, ulong size)
+        public static bool Commit(IntPtr address, ulong size, bool forJit)
         {
             if (OperatingSystem.IsWindows())
             {
@@ -44,7 +44,7 @@ namespace Ryujinx.Memory
             }
             else if (OperatingSystem.IsLinux() || OperatingSystem.IsMacOS())
             {
-                return MemoryManagementUnix.Commit(address, size);
+                return MemoryManagementUnix.Commit(address, size, forJit);
             }
             else
             {
diff --git a/Ryujinx.Memory/MemoryManagementUnix.cs b/Ryujinx.Memory/MemoryManagementUnix.cs
index df3fcea9..affcff92 100644
--- a/Ryujinx.Memory/MemoryManagementUnix.cs
+++ b/Ryujinx.Memory/MemoryManagementUnix.cs
@@ -13,17 +13,17 @@ namespace Ryujinx.Memory
     {
         private static readonly ConcurrentDictionary<IntPtr, ulong> _allocations = new ConcurrentDictionary<IntPtr, ulong>();
 
-        public static IntPtr Allocate(ulong size)
+        public static IntPtr Allocate(ulong size, bool forJit)
         {
-            return AllocateInternal(size, MmapProts.PROT_READ | MmapProts.PROT_WRITE);
+            return AllocateInternal(size, MmapProts.PROT_READ | MmapProts.PROT_WRITE, forJit);
         }
 
-        public static IntPtr Reserve(ulong size)
+        public static IntPtr Reserve(ulong size, bool forJit)
         {
-            return AllocateInternal(size, MmapProts.PROT_NONE);
+            return AllocateInternal(size, MmapProts.PROT_NONE, forJit);
         }
 
-        private static IntPtr AllocateInternal(ulong size, MmapProts prot, bool shared = false)
+        private static IntPtr AllocateInternal(ulong size, MmapProts prot, bool forJit, bool shared = false)
         {
             MmapFlags flags = MmapFlags.MAP_ANONYMOUS;
 
@@ -41,6 +41,16 @@ namespace Ryujinx.Memory
                 flags |= MmapFlags.MAP_NORESERVE;
             }
 
+            if (OperatingSystem.IsMacOSVersionAtLeast(10, 14) && forJit)
+            {
+                flags |= MmapFlags.MAP_JIT_DARWIN;
+
+                if (prot == (MmapProts.PROT_READ | MmapProts.PROT_WRITE))
+                {
+                    prot |= MmapProts.PROT_EXEC;
+                }
+            }
+
             IntPtr ptr = mmap(IntPtr.Zero, size, prot, flags, -1, 0);
 
             if (ptr == new IntPtr(-1L))
@@ -57,9 +67,16 @@ namespace Ryujinx.Memory
             return ptr;
         }
 
-        public static bool Commit(IntPtr address, ulong size)
+        public static bool Commit(IntPtr address, ulong size, bool forJit)
         {
-            return mprotect(address, size, MmapProts.PROT_READ | MmapProts.PROT_WRITE) == 0;
+            MmapProts prot = MmapProts.PROT_READ | MmapProts.PROT_WRITE;
+
+            if (OperatingSystem.IsMacOSVersionAtLeast(10, 14) && forJit)
+            {
+                prot |= MmapProts.PROT_EXEC;
+            }
+
+            return mprotect(address, size, prot) == 0;
         }
 
         public static bool Decommit(IntPtr address, ulong size)
diff --git a/Ryujinx.Memory/MemoryManagerUnixHelper.cs b/Ryujinx.Memory/MemoryManagerUnixHelper.cs
index 87a81a79..204f1ca4 100644
--- a/Ryujinx.Memory/MemoryManagerUnixHelper.cs
+++ b/Ryujinx.Memory/MemoryManagerUnixHelper.cs
@@ -22,7 +22,8 @@ namespace Ryujinx.Memory
             MAP_ANONYMOUS = 4,
             MAP_NORESERVE = 8,
             MAP_FIXED = 16,
-            MAP_UNLOCKED = 32
+            MAP_UNLOCKED = 32,
+            MAP_JIT_DARWIN = 0x800
         }
 
         [Flags]
@@ -45,7 +46,6 @@ namespace Ryujinx.Memory
         private const int MAP_UNLOCKED_LINUX_GENERIC = 0x80000;
 
         private const int MAP_NORESERVE_DARWIN = 0x40;
-        private const int MAP_JIT_DARWIN = 0x800;
         private const int MAP_ANONYMOUS_DARWIN = 0x1000;
 
         public const int MADV_DONTNEED = 4;
@@ -151,10 +151,9 @@ namespace Ryujinx.Memory
                 }
             }
 
-            if (OperatingSystem.IsMacOSVersionAtLeast(10, 14))
+            if (flags.HasFlag(MmapFlags.MAP_JIT_DARWIN) && OperatingSystem.IsMacOSVersionAtLeast(10, 14))
             {
-                // Only to be used with the Hardened Runtime.
-                // result |= MAP_JIT_DARWIN;
+                result |= (int)MmapFlags.MAP_JIT_DARWIN;
             }
 
             return result;