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Author: merry, svc64

src/Ryujinx.Cpu/AppleHv/Arm/ExceptionLevel.cs

@@ -0,0 +1,10 @@
+namespace Ryujinx.Cpu.AppleHv.Arm
+{
+    enum ExceptionLevel : uint
+    {
+        PstateMask = 0xfffffff0,
+        EL1h = 0b0101,
+        El1t = 0b0100,
+        EL0 = 0b0000,
+    }
+}

src/Ryujinx.Cpu/AppleHv/HvExecutionContext.cs

@@ -11,7 +11,18 @@ namespace Ryujinx.Cpu.AppleHv
     class HvExecutionContext : IExecutionContext
     {
         /// <inheritdoc/>
-        public ulong Pc => _impl.ElrEl1;
+        public ulong Pc
+        {
+            get
+            {
+                uint currentEl = Pstate & ~((uint)ExceptionLevel.PstateMask);
+                if (currentEl == (uint)ExceptionLevel.EL1h)
+                {
+                    return _impl.ElrEl1;
+                }
+                return _impl.Pc;
+            }
+        }
 
         /// <inheritdoc/>
         public long TpidrEl0
@@ -48,6 +59,9 @@ namespace Ryujinx.Cpu.AppleHv
             set => _impl.Fpsr = value;
         }
 
+        /// <inheritdoc/>
+        public ulong ThreadUid { get; set; }
+
         /// <inheritdoc/>
         public bool IsAarch32
         {
@@ -67,6 +81,7 @@ namespace Ryujinx.Cpu.AppleHv
         private readonly ICounter _counter;
         private readonly IHvExecutionContext _shadowContext;
         private IHvExecutionContext _impl;
+        private int _shouldStep;
 
         private readonly ExceptionCallbacks _exceptionCallbacks;
 
@@ -103,6 +118,11 @@ namespace Ryujinx.Cpu.AppleHv
             _exceptionCallbacks.BreakCallback?.Invoke(this, address, imm);
         }
 
+        private void StepHandler()
+        {
+            _exceptionCallbacks.StepCallback?.Invoke(this);
+        }
+
         private void SupervisorCallHandler(ulong address, int imm)
         {
             _exceptionCallbacks.SupervisorCallback?.Invoke(this, address, imm);
@@ -127,6 +147,30 @@ namespace Ryujinx.Cpu.AppleHv
             return Interlocked.Exchange(ref _interruptRequested, 0) != 0;
         }
 
+        /// <inheritdoc/>
+        public void RequestDebugStep()
+        {
+            Interlocked.Exchange(ref _shouldStep, 1);
+        }
+
+        /// <inheritdoc/>
+        public ulong DebugPc
+        {
+            get => Pc;
+            set
+            {
+                uint currentEl = Pstate & ~((uint)ExceptionLevel.PstateMask);
+                if (currentEl == (uint)ExceptionLevel.EL1h)
+                {
+                    _impl.ElrEl1 = value;
+                }
+                else
+                {
+                    _impl.Pc = value;
+                }
+            }
+        }
+
         /// <inheritdoc/>
         public void StopRunning()
         {
@@ -142,6 +186,22 @@ namespace Ryujinx.Cpu.AppleHv
 
             while (Running)
             {
+                if (Interlocked.CompareExchange(ref _shouldStep, 0, 1) == 1)
+                {
+                    uint currentEl = Pstate & ~((uint)ExceptionLevel.PstateMask);
+                    if (currentEl == (uint)ExceptionLevel.EL1h)
+                    {
+                        HvApi.hv_vcpu_get_sys_reg(vcpu.Handle, HvSysReg.SPSR_EL1, out ulong spsr).ThrowOnError();
+                        spsr |= (1 << 21);
+                        HvApi.hv_vcpu_set_sys_reg(vcpu.Handle, HvSysReg.SPSR_EL1, spsr);
+                    }
+                    else
+                    {
+                        Pstate |= (1 << 21);
+                    }
+                    HvApi.hv_vcpu_set_sys_reg(vcpu.Handle, HvSysReg.MDSCR_EL1, 1);
+                }
+
                 HvApi.hv_vcpu_run(vcpu.Handle).ThrowOnError();
 
                 HvExitReason reason = vcpu.ExitInfo->Reason;
@@ -209,6 +269,20 @@ namespace Ryujinx.Cpu.AppleHv
                     SupervisorCallHandler(elr - 4UL, id);
                     vcpu = RentFromPool(memoryManager.AddressSpace, vcpu);
                     break;
+                case ExceptionClass.SoftwareStepLowerEl:
+                    HvApi.hv_vcpu_get_sys_reg(vcpuHandle, HvSysReg.SPSR_EL1, out ulong spsr).ThrowOnError();
+                    spsr &= ~((ulong)(1 << 21));
+                    HvApi.hv_vcpu_set_sys_reg(vcpuHandle, HvSysReg.SPSR_EL1, spsr).ThrowOnError();
+                    HvApi.hv_vcpu_set_sys_reg(vcpuHandle, HvSysReg.MDSCR_EL1, 0);
+                    ReturnToPool(vcpu);
+                    StepHandler();
+                    vcpu = RentFromPool(memoryManager.AddressSpace, vcpu);
+                    break;
+                case ExceptionClass.BrkAarch64:
+                    ReturnToPool(vcpu);
+                    BreakHandler(elr, (ushort)esr);
+                    vcpu = RentFromPool(memoryManager.AddressSpace, vcpu);
+                    break;
                 default:
                     throw new Exception($"Unhandled guest exception {ec}.");
             }
@@ -219,10 +293,7 @@ namespace Ryujinx.Cpu.AppleHv
                 // TODO: Invalidate only the range that was modified?
                 return HvAddressSpace.KernelRegionTlbiEretAddress;
             }
-            else
-            {
-                return HvAddressSpace.KernelRegionEretAddress;
-            }
+            return HvAddressSpace.KernelRegionEretAddress;
         }
 
         private static void DataAbort(MemoryTracking tracking, ulong vcpu, uint esr)

src/Ryujinx.Cpu/AppleHv/HvExecutionContextShadow.cs

@@ -18,6 +18,8 @@ namespace Ryujinx.Cpu.AppleHv
 
         public bool IsAarch32 { get; set; }
 
+        public ulong ThreadUid { get; set; }
+
         private readonly ulong[] _x;
         private readonly V128[] _v;
 
@@ -46,5 +48,14 @@ namespace Ryujinx.Cpu.AppleHv
         {
             _v[index] = value;
         }
+
+        public void RequestInterrupt()
+        {
+        }
+
+        public bool GetAndClearInterruptRequested()
+        {
+            return false;
+        }
     }
 }

src/Ryujinx.Cpu/AppleHv/HvExecutionContextVcpu.cs

@@ -2,6 +2,7 @@ using ARMeilleure.State;
 using Ryujinx.Memory;
 using System.Runtime.InteropServices;
 using System.Runtime.Versioning;
+using System.Threading;
 
 namespace Ryujinx.Cpu.AppleHv
 {
@@ -13,6 +14,8 @@ namespace Ryujinx.Cpu.AppleHv
         private static readonly SetSimdFpReg _setSimdFpReg;
         private static readonly nint _setSimdFpRegNativePtr;
 
+        public ulong ThreadUid { get; set; }
+
         static HvExecutionContextVcpu()
         {
             // .NET does not support passing vectors by value, so we need to pass a pointer and use a native
@@ -135,6 +138,7 @@ namespace Ryujinx.Cpu.AppleHv
         }
 
         private readonly ulong _vcpu;
+        private int _interruptRequested;
 
         public HvExecutionContextVcpu(ulong vcpu)
         {
@@ -180,8 +184,16 @@ namespace Ryujinx.Cpu.AppleHv
 
         public void RequestInterrupt()
         {
-            ulong vcpu = _vcpu;
-            HvApi.hv_vcpus_exit(ref vcpu, 1);
+            if (Interlocked.Exchange(ref _interruptRequested, 1) == 0)
+            {
+                ulong vcpu = _vcpu;
+                HvApi.hv_vcpus_exit(ref vcpu, 1);
+            }
+        }
+
+        public bool GetAndClearInterruptRequested()
+        {
+            return Interlocked.Exchange(ref _interruptRequested, 0) != 0;
         }
     }
 }

src/Ryujinx.Cpu/AppleHv/IHvExecutionContext.cs

@@ -15,6 +15,7 @@ namespace Ryujinx.Cpu.AppleHv
 
         uint Fpcr { get; set; }
         uint Fpsr { get; set; }
+        ulong ThreadUid { get; set; }
 
         ulong GetX(int index);
         void SetX(int index, ulong value);
@@ -39,5 +40,8 @@ namespace Ryujinx.Cpu.AppleHv
                 SetV(i, context.GetV(i));
             }
         }
+
+        void RequestInterrupt();
+        bool GetAndClearInterruptRequested();
     }
 }

src/Ryujinx.Cpu/ExceptionCallbacks.cs

@@ -29,6 +29,11 @@ namespace Ryujinx.Cpu
         /// </summary>
         public readonly ExceptionCallback BreakCallback;
 
+        /// <summary>
+        /// Handler for CPU software interrupts caused by single-stepping.
+        /// </summary>
+        public readonly ExceptionCallbackNoArgs StepCallback;
+
         /// <summary>
         /// Handler for CPU software interrupts caused by the Arm SVC instruction.
         /// </summary>
@@ -47,16 +52,19 @@ namespace Ryujinx.Cpu
         /// </remarks>
         /// <param name="interruptCallback">Handler for CPU interrupts triggered using <see cref="IExecutionContext.RequestInterrupt"/></param>
         /// <param name="breakCallback">Handler for CPU software interrupts caused by the Arm BRK instruction</param>
+        /// <param name="stepCallback">Handler for CPU software interrupts caused by single-stepping</param>
         /// <param name="supervisorCallback">Handler for CPU software interrupts caused by the Arm SVC instruction</param>
         /// <param name="undefinedCallback">Handler for CPU software interrupts caused by any undefined Arm instruction</param>
         public ExceptionCallbacks(
             ExceptionCallbackNoArgs interruptCallback = null,
             ExceptionCallback breakCallback = null,
+            ExceptionCallbackNoArgs stepCallback = null,
             ExceptionCallback supervisorCallback = null,
             ExceptionCallback undefinedCallback = null)
         {
             InterruptCallback = interruptCallback;
             BreakCallback = breakCallback;
+            StepCallback = stepCallback;
             SupervisorCallback = supervisorCallback;
             UndefinedCallback = undefinedCallback;
         }

src/Ryujinx.Cpu/IExecutionContext.cs

@@ -1,5 +1,6 @@
 using ARMeilleure.State;
 using System;
+using System.Threading;
 
 namespace Ryujinx.Cpu
 {
@@ -46,6 +47,11 @@ namespace Ryujinx.Cpu
         /// </summary>
         bool IsAarch32 { get; set; }
 
+        /// <summary>
+        /// Thread UID.
+        /// </summary>
+        public ulong ThreadUid { get; set; }
+
         /// <summary>
         /// Indicates whenever the CPU is still running code.
         /// </summary>
@@ -108,5 +114,23 @@ namespace Ryujinx.Cpu
         /// If you only need to pause the thread temporarily, use <see cref="RequestInterrupt"/> instead.
         /// </remarks>
         void StopRunning();
+
+        /// <summary>
+        /// Requests the thread to stop running temporarily and call <see cref="ExceptionCallbacks.InterruptCallback"/>.
+        /// </summary>
+        /// <remarks>
+        /// The thread might not pause immediately.
+        /// One must not assume that guest code is no longer being executed by the thread after calling this function.
+        /// After single stepping, the thread should call call <see cref="ExceptionCallbacks.StepCallback"/>.
+        /// </remarks>
+        void RequestDebugStep();
+
+        /// <summary>
+        /// Current Program Counter (for debugging).
+        /// </summary>
+        /// <remarks>
+        /// PC register for the debugger. Must not be accessed while the thread isn't stopped for debugging.
+        /// </remarks>
+        ulong DebugPc { get; set; }
     }
 }

src/Ryujinx.Cpu/Jit/JitExecutionContext.cs

@@ -1,5 +1,7 @@
 using ARMeilleure.Memory;
 using ARMeilleure.State;
+using System.Threading;
+using ExecutionContext = ARMeilleure.State.ExecutionContext;
 
 namespace Ryujinx.Cpu.Jit
 {
@@ -53,6 +55,13 @@ namespace Ryujinx.Cpu.Jit
             set => _impl.IsAarch32 = value;
         }
 
+        /// <inheritdoc/>
+        public ulong ThreadUid
+        {
+            get => _impl.ThreadUid;
+            set => _impl.ThreadUid = value;
+        }
+
         /// <inheritdoc/>
         public bool Running => _impl.Running;
 
@@ -65,6 +74,7 @@ namespace Ryujinx.Cpu.Jit
                 counter,
                 InterruptHandler,
                 BreakHandler,
+                StepHandler,
                 SupervisorCallHandler,
                 UndefinedHandler);
 
@@ -93,6 +103,11 @@ namespace Ryujinx.Cpu.Jit
             _exceptionCallbacks.BreakCallback?.Invoke(this, address, imm);
         }
 
+        private void StepHandler(ExecutionContext context)
+        {
+            _exceptionCallbacks.StepCallback?.Invoke(this);
+        }
+
         private void SupervisorCallHandler(ExecutionContext context, ulong address, int imm)
         {
             _exceptionCallbacks.SupervisorCallback?.Invoke(this, address, imm);
@@ -109,6 +124,16 @@ namespace Ryujinx.Cpu.Jit
             _impl.RequestInterrupt();
         }
 
+        /// <inheritdoc/>
+        public void RequestDebugStep() => _impl.RequestDebugStep();
+
+        /// <inheritdoc/>
+        public ulong DebugPc
+        {
+            get => _impl.DebugPc;
+            set => _impl.DebugPc = value;
+        }
+
         /// <inheritdoc/>
         public void StopRunning()
         {

src/Ryujinx.Cpu/LightningJit/State/ExecutionContext.cs

@@ -1,6 +1,7 @@
 using ARMeilleure.Memory;
 using ARMeilleure.State;
 using System;
+using System.Threading;
 
 namespace Ryujinx.Cpu.LightningJit.State
 {
@@ -51,6 +52,8 @@ namespace Ryujinx.Cpu.LightningJit.State
         }
 
         public bool IsAarch32 { get; set; }
+        
+        public ulong ThreadUid { get; set; }
 
         internal ExecutionMode ExecutionMode
         {
@@ -77,15 +80,20 @@ namespace Ryujinx.Cpu.LightningJit.State
 
         private readonly ExceptionCallbackNoArgs _interruptCallback;
         private readonly ExceptionCallback _breakCallback;
+        private readonly ExceptionCallbackNoArgs _stepCallback;
         private readonly ExceptionCallback _supervisorCallback;
         private readonly ExceptionCallback _undefinedCallback;
 
+        internal int ShouldStep;
+        public ulong DebugPc { get; set; }
+
         public ExecutionContext(IJitMemoryAllocator allocator, ICounter counter, ExceptionCallbacks exceptionCallbacks)
         {
             _nativeContext = new NativeContext(allocator);
             _counter = counter;
             _interruptCallback = exceptionCallbacks.InterruptCallback;
             _breakCallback = exceptionCallbacks.BreakCallback;
+            _stepCallback = exceptionCallbacks.StepCallback;
             _supervisorCallback = exceptionCallbacks.SupervisorCallback;
             _undefinedCallback = exceptionCallbacks.UndefinedCallback;
 
@@ -117,6 +125,17 @@ namespace Ryujinx.Cpu.LightningJit.State
             _interrupted = true;
         }
 
+        public void StepHandler()
+        {
+            _stepCallback.Invoke(this);
+        }
+
+        public void RequestDebugStep()
+        {
+            Interlocked.Exchange(ref ShouldStep, 1);
+            RequestInterrupt();
+        }
+
         internal void OnBreak(ulong address, int imm)
         {
             _breakCallback?.Invoke(this, address, imm);