Refactor CPU interface to allow the implementation of other CPU emulators (#3362)

* Refactor CPU interface

* Use IExecutionContext interface on SVC handler, change how CPU interrupts invokes the handlers

* Make CpuEngine take a ITickSource rather than returning one

The previous implementation had the scenario where the CPU engine had to implement the tick source in mind, like for example, when we have a hypervisor and the game can read CNTPCT on the host directly. However given that we need to do conversion due to different frequencies anyway, it's not worth it. It's better to just let the user pass the tick source and redirect any reads to CNTPCT to the user tick source

* XML docs for the public interfaces

* PPTC invalidation due to NativeInterface function name changes

* Fix build of the CPU tests

* PR feedback

11 files changed, 112 insertions, 59 deletions

diff --git a/Ryujinx.HLE/HOS/Kernel/KernelConstants.cs b/Ryujinx.HLE/HOS/Kernel/KernelConstants.cs
index 5a1dbef2..3817b0aa 100644
--- a/Ryujinx.HLE/HOS/Kernel/KernelConstants.cs
+++ b/Ryujinx.HLE/HOS/Kernel/KernelConstants.cs
@@ -12,5 +12,7 @@ namespace Ryujinx.HLE.HOS.Kernel
         public const ulong UserSlabHeapBase = DramMemoryMap.SlabHeapBase;
         public const ulong UserSlabHeapItemSize = KPageTableBase.PageSize;
         public const ulong UserSlabHeapSize = 0x3de000;
+
+        public const ulong CounterFrequency = 19200000;
     }
 }
diff --git a/Ryujinx.HLE/HOS/Kernel/KernelContext.cs b/Ryujinx.HLE/HOS/Kernel/KernelContext.cs
index 4b8e4d15..6c58e197 100644
--- a/Ryujinx.HLE/HOS/Kernel/KernelContext.cs
+++ b/Ryujinx.HLE/HOS/Kernel/KernelContext.cs
@@ -1,4 +1,5 @@
-using Ryujinx.HLE.HOS.Kernel.Common;
+using Ryujinx.Cpu;
+using Ryujinx.HLE.HOS.Kernel.Common;
 using Ryujinx.HLE.HOS.Kernel.Memory;
 using Ryujinx.HLE.HOS.Kernel.Process;
 using Ryujinx.HLE.HOS.Kernel.SupervisorCall;
@@ -23,6 +24,7 @@ namespace Ryujinx.HLE.HOS.Kernel
 
         public Switch Device { get; }
         public MemoryBlock Memory { get; }
+        public ITickSource TickSource { get; }
         public Syscall Syscall { get; }
         public SyscallHandler SyscallHandler { get; }
 
@@ -52,11 +54,13 @@ namespace Ryujinx.HLE.HOS.Kernel
         private ulong _threadUid;
 
         public KernelContext(
+            ITickSource tickSource,
             Switch device,
             MemoryBlock memory,
             MemorySize memorySize,
             MemoryArrange memoryArrange)
         {
+            TickSource = tickSource;
             Device = device;
             Memory = memory;
 
diff --git a/Ryujinx.HLE/HOS/Kernel/Process/HleProcessDebugger.cs b/Ryujinx.HLE/HOS/Kernel/Process/HleProcessDebugger.cs
index e0cd4fbf..0a78a26d 100644
--- a/Ryujinx.HLE/HOS/Kernel/Process/HleProcessDebugger.cs
+++ b/Ryujinx.HLE/HOS/Kernel/Process/HleProcessDebugger.cs
@@ -115,7 +115,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Process
 
             string GetReg(int x)
             {
-                var v = x == 32 ? (ulong)thread.LastPc : context.GetX(x);
+                var v = x == 32 ? context.Pc : context.GetX(x);
                 if (!AnalyzePointer(out PointerInfo info, v, thread))
                 {
                     return $"0x{v:x16}";
diff --git a/Ryujinx.HLE/HOS/Kernel/Process/IProcessContext.cs b/Ryujinx.HLE/HOS/Kernel/Process/IProcessContext.cs
index 707e6d98..c8063a62 100644
--- a/Ryujinx.HLE/HOS/Kernel/Process/IProcessContext.cs
+++ b/Ryujinx.HLE/HOS/Kernel/Process/IProcessContext.cs
@@ -1,4 +1,4 @@
-using ARMeilleure.State;
+using Ryujinx.Cpu;
 using Ryujinx.Memory;
 using System;
 
@@ -8,7 +8,8 @@ namespace Ryujinx.HLE.HOS.Kernel.Process
     {
         IVirtualMemoryManager AddressSpace { get; }
 
-        void Execute(ExecutionContext context, ulong codeAddress);
+        IExecutionContext CreateExecutionContext(ExceptionCallbacks exceptionCallbacks);
+        void Execute(IExecutionContext context, ulong codeAddress);
         void InvalidateCacheRegion(ulong address, ulong size);
     }
 }
diff --git a/Ryujinx.HLE/HOS/Kernel/Process/KProcess.cs b/Ryujinx.HLE/HOS/Kernel/Process/KProcess.cs
index b10737b4..0caeacad 100644
--- a/Ryujinx.HLE/HOS/Kernel/Process/KProcess.cs
+++ b/Ryujinx.HLE/HOS/Kernel/Process/KProcess.cs
@@ -1,4 +1,3 @@
-using ARMeilleure.State;
 using Ryujinx.Common;
 using Ryujinx.Common.Logging;
 using Ryujinx.Cpu;
@@ -744,14 +743,16 @@ namespace Ryujinx.HLE.HOS.Kernel.Process
             }
         }
 
-        public void SubscribeThreadEventHandlers(ARMeilleure.State.ExecutionContext context)
+        public IExecutionContext CreateExecutionContext()
         {
-            context.Interrupt += InterruptHandler;
-            context.SupervisorCall += KernelContext.SyscallHandler.SvcCall;
-            context.Undefined += UndefinedInstructionHandler;
+            return Context?.CreateExecutionContext(new ExceptionCallbacks(
+                InterruptHandler,
+                null,
+                KernelContext.SyscallHandler.SvcCall,
+                UndefinedInstructionHandler));
         }
 
-        private void InterruptHandler(object sender, EventArgs e)
+        private void InterruptHandler(IExecutionContext context)
         {
             KThread currentThread = KernelStatic.GetCurrentThread();
 
@@ -1093,12 +1094,12 @@ namespace Ryujinx.HLE.HOS.Kernel.Process
             return false;
         }
 
-        private void UndefinedInstructionHandler(object sender, InstUndefinedEventArgs e)
+        private void UndefinedInstructionHandler(IExecutionContext context, ulong address, int opCode)
         {
             KernelStatic.GetCurrentThread().PrintGuestStackTrace();
             KernelStatic.GetCurrentThread()?.PrintGuestRegisterPrintout();
 
-            throw new UndefinedInstructionException(e.Address, e.OpCode);
+            throw new UndefinedInstructionException(address, opCode);
         }
 
         protected override void Destroy() => Context.Dispose();
diff --git a/Ryujinx.HLE/HOS/Kernel/Process/ProcessContext.cs b/Ryujinx.HLE/HOS/Kernel/Process/ProcessContext.cs
index bb3a1557..87296830 100644
--- a/Ryujinx.HLE/HOS/Kernel/Process/ProcessContext.cs
+++ b/Ryujinx.HLE/HOS/Kernel/Process/ProcessContext.cs
@@ -1,4 +1,4 @@
-using ARMeilleure.State;
+using Ryujinx.Cpu;
 using Ryujinx.Memory;
 using System;
 
@@ -13,7 +13,12 @@ namespace Ryujinx.HLE.HOS.Kernel.Process
             AddressSpace = asManager;
         }
 
-        public void Execute(ExecutionContext context, ulong codeAddress)
+        public IExecutionContext CreateExecutionContext(ExceptionCallbacks exceptionCallbacks)
+        {
+            return new ProcessExecutionContext();
+        }
+
+        public void Execute(IExecutionContext context, ulong codeAddress)
         {
             throw new NotSupportedException();
         }
diff --git a/Ryujinx.HLE/HOS/Kernel/Process/ProcessExecutionContext.cs b/Ryujinx.HLE/HOS/Kernel/Process/ProcessExecutionContext.cs
new file mode 100644
index 00000000..a0841252
--- /dev/null
+++ b/Ryujinx.HLE/HOS/Kernel/Process/ProcessExecutionContext.cs
@@ -0,0 +1,44 @@
+using ARMeilleure.State;
+using Ryujinx.Cpu;
+
+namespace Ryujinx.HLE.HOS.Kernel.Process
+{
+    class ProcessExecutionContext : IExecutionContext
+    {
+        public ulong Pc => 0UL;
+
+        public ulong CntfrqEl0 { get => 0; set { } }
+        public ulong CntpctEl0 => 0UL;
+
+        public long TpidrEl0 { get => 0; set { } }
+        public long TpidrroEl0 { get => 0; set { } }
+
+        public uint Pstate { get => 0; set { } }
+
+        public uint Fpcr { get => 0; set { } }
+        public uint Fpsr { get => 0; set { } }
+
+        public bool IsAarch32 { get => false; set { } }
+
+        public bool Running { get; private set; } = true;
+
+        public ulong GetX(int index) => 0UL;
+        public void SetX(int index, ulong value) { }
+
+        public V128 GetV(int index) => default;
+        public void SetV(int index, V128 value) { }
+
+        public void RequestInterrupt()
+        {
+        }
+
+        public void StopRunning()
+        {
+            Running = false;
+        }
+
+        public void Dispose()
+        {
+        }
+    }
+}
\ No newline at end of file
diff --git a/Ryujinx.HLE/HOS/Kernel/SupervisorCall/Syscall.cs b/Ryujinx.HLE/HOS/Kernel/SupervisorCall/Syscall.cs
index d9d492a5..571699d9 100644
--- a/Ryujinx.HLE/HOS/Kernel/SupervisorCall/Syscall.cs
+++ b/Ryujinx.HLE/HOS/Kernel/SupervisorCall/Syscall.cs
@@ -1755,7 +1755,7 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
 
         public ulong GetSystemTick()
         {
-            return KernelStatic.GetCurrentThread().Context.CntpctEl0;
+            return _context.TickSource.Counter;
         }
 
         public void Break(ulong reason)
diff --git a/Ryujinx.HLE/HOS/Kernel/SupervisorCall/SyscallHandler.cs b/Ryujinx.HLE/HOS/Kernel/SupervisorCall/SyscallHandler.cs
index 5e795d35..cb693f59 100644
--- a/Ryujinx.HLE/HOS/Kernel/SupervisorCall/SyscallHandler.cs
+++ b/Ryujinx.HLE/HOS/Kernel/SupervisorCall/SyscallHandler.cs
@@ -1,4 +1,4 @@
-using ARMeilleure.State;
+using Ryujinx.Cpu;
 using Ryujinx.HLE.HOS.Kernel.Threading;
 using System;
 
@@ -17,7 +17,7 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
             _syscall64 = new Syscall64(context.Syscall);
         }
 
-        public void SvcCall(object sender, InstExceptionEventArgs e)
+        public void SvcCall(IExecutionContext context, ulong address, int id)
         {
             KThread currentThread = KernelStatic.GetCurrentThread();
 
@@ -34,26 +34,24 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
                 _context.CriticalSection.Leave();
             }
 
-            ExecutionContext context = (ExecutionContext)sender; 
-
             if (context.IsAarch32)
             {
-                var svcFunc = SyscallTable.SvcTable32[e.Id];
+                var svcFunc = SyscallTable.SvcTable32[id];
 
                 if (svcFunc == null)
                 {
-                    throw new NotImplementedException($"SVC 0x{e.Id:X4} is not implemented.");
+                    throw new NotImplementedException($"SVC 0x{id:X4} is not implemented.");
                 }
 
                 svcFunc(_syscall32, context);
             }
             else
             {
-                var svcFunc = SyscallTable.SvcTable64[e.Id];
+                var svcFunc = SyscallTable.SvcTable64[id];
 
                 if (svcFunc == null)
                 {
-                    throw new NotImplementedException($"SVC 0x{e.Id:X4} is not implemented.");
+                    throw new NotImplementedException($"SVC 0x{id:X4} is not implemented.");
                 }
 
                 svcFunc(_syscall64, context);
diff --git a/Ryujinx.HLE/HOS/Kernel/SupervisorCall/SyscallTable.cs b/Ryujinx.HLE/HOS/Kernel/SupervisorCall/SyscallTable.cs
index 6e0b7010..8b7e7fb8 100644
--- a/Ryujinx.HLE/HOS/Kernel/SupervisorCall/SyscallTable.cs
+++ b/Ryujinx.HLE/HOS/Kernel/SupervisorCall/SyscallTable.cs
@@ -1,5 +1,5 @@
-using ARMeilleure.State;
 using Ryujinx.Common.Logging;
+using Ryujinx.Cpu;
 using Ryujinx.HLE.HOS.Kernel.Common;
 using System;
 using System.Collections.Generic;
@@ -14,13 +14,13 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
         private const int SvcFuncMaxArguments32 = 4;
         private const int SvcMax                = 0x80;
 
-        public static Action<Syscall32, ExecutionContext>[] SvcTable32 { get; }
-        public static Action<Syscall64, ExecutionContext>[] SvcTable64 { get; }
+        public static Action<Syscall32, IExecutionContext>[] SvcTable32 { get; }
+        public static Action<Syscall64, IExecutionContext>[] SvcTable64 { get; }
 
         static SyscallTable()
         {
-            SvcTable32 = new Action<Syscall32, ExecutionContext>[SvcMax];
-            SvcTable64 = new Action<Syscall64, ExecutionContext>[SvcMax];
+            SvcTable32 = new Action<Syscall32, IExecutionContext>[SvcMax];
+            SvcTable64 = new Action<Syscall64, IExecutionContext>[SvcMax];
 
             Dictionary<int, string> svcFuncs64 = new Dictionary<int, string>
             {
@@ -182,9 +182,9 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
             }
         }
 
-        private static Action<T, ExecutionContext> GenerateMethod<T>(string svcName, int registerCleanCount)
+        private static Action<T, IExecutionContext> GenerateMethod<T>(string svcName, int registerCleanCount)
         {
-            Type[] argTypes = new Type[] { typeof(T), typeof(ExecutionContext) };
+            Type[] argTypes = new Type[] { typeof(T), typeof(IExecutionContext) };
 
             DynamicMethod method = new DynamicMethod(svcName, null, argTypes);
 
@@ -292,9 +292,9 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
                     generator.Emit(OpCodes.Ldarg_1);
                     generator.Emit(OpCodes.Ldc_I4, registerAttribute.Index);
 
-                    MethodInfo info = typeof(ExecutionContext).GetMethod(nameof(ExecutionContext.GetX));
+                    MethodInfo info = typeof(IExecutionContext).GetMethod(nameof(IExecutionContext.GetX));
 
-                    generator.Emit(OpCodes.Call, info);
+                    generator.Emit(OpCodes.Callvirt, info);
 
                     generator.Emit(OpCodes.Box, typeof(ulong));
 
@@ -339,9 +339,9 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
                         generator.Emit(OpCodes.Ldarg_1);
                         generator.Emit(OpCodes.Ldc_I4, registerAttribute.Index);
 
-                        MethodInfo info = typeof(ExecutionContext).GetMethod(nameof(ExecutionContext.GetX));
+                        MethodInfo info = typeof(IExecutionContext).GetMethod(nameof(IExecutionContext.GetX));
 
-                        generator.Emit(OpCodes.Call, info);
+                        generator.Emit(OpCodes.Callvirt, info);
 
                         ConvertToArgType(argType);
 
@@ -355,9 +355,9 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
                     generator.Emit(OpCodes.Ldarg_1);
                     generator.Emit(OpCodes.Ldc_I4, registerAttribute.Index);
 
-                    MethodInfo info = typeof(ExecutionContext).GetMethod(nameof(ExecutionContext.GetX));
+                    MethodInfo info = typeof(IExecutionContext).GetMethod(nameof(IExecutionContext.GetX));
 
-                    generator.Emit(OpCodes.Call, info);
+                    generator.Emit(OpCodes.Callvirt, info);
 
                     ConvertToArgType(argType);
                 }
@@ -393,9 +393,9 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
 
                 ConvertToFieldType(retType);
 
-                MethodInfo info = typeof(ExecutionContext).GetMethod(nameof(ExecutionContext.SetX));
+                MethodInfo info = typeof(IExecutionContext).GetMethod(nameof(IExecutionContext.SetX));
 
-                generator.Emit(OpCodes.Call, info);
+                generator.Emit(OpCodes.Callvirt, info);
 
                 registerInUse |= 1u << 0;
             }
@@ -415,9 +415,9 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
 
                 ConvertToFieldType(local.LocalType);
 
-                MethodInfo info = typeof(ExecutionContext).GetMethod(nameof(ExecutionContext.SetX));
+                MethodInfo info = typeof(IExecutionContext).GetMethod(nameof(IExecutionContext.SetX));
 
-                generator.Emit(OpCodes.Call, info);
+                generator.Emit(OpCodes.Callvirt, info);
 
                 registerInUse |= 1u << attribute.Index;
             }
@@ -434,14 +434,14 @@ namespace Ryujinx.HLE.HOS.Kernel.SupervisorCall
                 generator.Emit(OpCodes.Ldc_I4, i);
                 generator.Emit(OpCodes.Ldc_I8, 0L);
 
-                MethodInfo info = typeof(ExecutionContext).GetMethod(nameof(ExecutionContext.SetX));
+                MethodInfo info = typeof(IExecutionContext).GetMethod(nameof(IExecutionContext.SetX));
 
-                generator.Emit(OpCodes.Call, info);
+                generator.Emit(OpCodes.Callvirt, info);
             }
 
             generator.Emit(OpCodes.Ret);
 
-            return method.CreateDelegate<Action<T, ExecutionContext>>();
+            return method.CreateDelegate<Action<T, IExecutionContext>>();
         }
 
         private static void CheckIfTypeIsSupported(Type type, string svcName)
diff --git a/Ryujinx.HLE/HOS/Kernel/Threading/KThread.cs b/Ryujinx.HLE/HOS/Kernel/Threading/KThread.cs
index ee701a69..b9dd91ef 100644
--- a/Ryujinx.HLE/HOS/Kernel/Threading/KThread.cs
+++ b/Ryujinx.HLE/HOS/Kernel/Threading/KThread.cs
@@ -23,7 +23,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
 
         public Thread HostThread { get; private set; }
 
-        public ARMeilleure.State.ExecutionContext Context { get; private set; }
+        public IExecutionContext Context { get; private set; }
 
         public KThreadContext ThreadContext { get; private set; }
 
@@ -115,9 +115,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
 
         public bool WaitingInArbitration { get; set; }
 
-        public long LastPc { get; set; }
-
-        private object ActivityOperationLock = new object();
+        private object _activityOperationLock;
 
         public KThread(KernelContext context) : base(context)
         {
@@ -128,6 +126,8 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
 
             _mutexWaiters = new LinkedList<KThread>();
             _pinnedWaiters = new LinkedList<KThread>();
+
+            _activityOperationLock = new object();
         }
 
         public KernelResult Initialize(
@@ -192,7 +192,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
 
             HostThread = new Thread(ThreadStart);
 
-            Context = CpuContext.CreateExecutionContext();
+            Context = owner?.CreateExecutionContext() ?? new ProcessExecutionContext();
 
             Context.IsAarch32 = !is64Bits;
 
@@ -208,8 +208,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
                 Context.SetX(13, (uint)stackTop);
             }
 
-            Context.CntfrqEl0 = 19200000;
-            Context.Tpidr = (long)_tlsAddress;
+            Context.TpidrroEl0 = (long)_tlsAddress;
 
             ThreadUid = KernelContext.NewThreadUid();
 
@@ -221,7 +220,6 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
 
             if (owner != null)
             {
-                owner.SubscribeThreadEventHandlers(Context);
                 owner.AddThread(this);
 
                 if (owner.IsPaused)
@@ -538,7 +536,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
 
         public KernelResult SetActivity(bool pause)
         {
-            lock (ActivityOperationLock)
+            lock (_activityOperationLock)
             {
                 KernelResult result = KernelResult.Success;
 
@@ -634,7 +632,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
         {
             context = default;
 
-            lock (ActivityOperationLock)
+            lock (_activityOperationLock)
             {
                 KernelContext.CriticalSection.Enter();
 
@@ -656,7 +654,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
             return KernelResult.Success;
         }
 
-        private static uint GetPsr(ARMeilleure.State.ExecutionContext context)
+        private static uint GetPsr(IExecutionContext context)
         {
             return context.Pstate & 0xFF0FFE20;
         }
@@ -683,9 +681,9 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
                 context.Fp = Context.GetX(29);
                 context.Lr = Context.GetX(30);
                 context.Sp = Context.GetX(31);
-                context.Pc = (ulong)LastPc;
+                context.Pc = Context.Pc;
                 context.Pstate = GetPsr(Context);
-                context.Tpidr = (ulong)Context.Tpidr;
+                context.Tpidr = (ulong)Context.TpidrroEl0;
             }
             else
             {
@@ -699,9 +697,9 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
                     context.FpuRegisters[i] = Context.GetV(i);
                 }
 
-                context.Pc = (uint)LastPc;
+                context.Pc = (uint)Context.Pc;
                 context.Pstate = GetPsr(Context);
-                context.Tpidr = (uint)Context.Tpidr;
+                context.Tpidr = (uint)Context.TpidrroEl0;
             }
 
             context.Fpcr = (uint)Context.Fpcr;
@@ -743,7 +741,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
 
         public KernelResult SetCoreAndAffinityMask(int newCore, ulong newAffinityMask)
         {
-            lock (ActivityOperationLock)
+            lock (_activityOperationLock)
             {
                 KernelContext.CriticalSection.Enter();