core/debugger: Implement new GDB stub debugger

src/core/arm/arm_interface.cpp

@@ -9,6 +9,7 @@
 #include "core/arm/arm_interface.h"
 #include "core/arm/symbols.h"
 #include "core/core.h"
+#include "core/debugger/debugger.h"
 #include "core/hle/kernel/k_process.h"
 #include "core/loader/loader.h"
 #include "core/memory.h"
@@ -88,4 +89,8 @@ void ARM_Interface::LogBacktrace() const {
     }
 }
 
+bool ARM_Interface::ShouldStep() const {
+    return system.DebuggerEnabled() && system.GetDebugger().IsStepping();
+}
+
 } // namespace Core

src/core/arm/arm_interface.h

@@ -66,9 +66,6 @@ public:
     /// Runs the CPU until an event happens
     virtual void Run() = 0;
 
-    /// Step CPU by one instruction
-    virtual void Step() = 0;
-
     /// Clear all instruction cache
     virtual void ClearInstructionCache() = 0;
 
@@ -194,6 +191,8 @@ public:
 
     void LogBacktrace() const;
 
+    bool ShouldStep() const;
+
 protected:
     /// System context that this ARM interface is running under.
     System& system;

src/core/arm/dynarmic/arm_dynarmic_32.cpp

@@ -17,6 +17,8 @@
 #include "core/arm/dynarmic/arm_exclusive_monitor.h"
 #include "core/core.h"
 #include "core/core_timing.h"
+#include "core/debugger/debugger.h"
+#include "core/hle/kernel/k_process.h"
 #include "core/hle/kernel/svc.h"
 #include "core/memory.h"
 
@@ -26,6 +28,7 @@ using namespace Common::Literals;
 
 constexpr Dynarmic::HaltReason break_loop = Dynarmic::HaltReason::UserDefined2;
 constexpr Dynarmic::HaltReason svc_call = Dynarmic::HaltReason::UserDefined3;
+constexpr Dynarmic::HaltReason breakpoint = Dynarmic::HaltReason::UserDefined4;
 
 class DynarmicCallbacks32 : public Dynarmic::A32::UserCallbacks {
 public:
@@ -78,11 +81,16 @@ public:
     }
 
     void ExceptionRaised(u32 pc, Dynarmic::A32::Exception exception) override {
+        if (parent.system.DebuggerEnabled()) {
+            parent.breakpoint_pc = pc;
+            parent.jit.load()->HaltExecution(breakpoint);
+            return;
+        }
+
         parent.LogBacktrace();
         LOG_CRITICAL(Core_ARM,
                      "ExceptionRaised(exception = {}, pc = {:08X}, code = {:08X}, thumb = {})",
                      exception, pc, MemoryReadCode(pc), parent.IsInThumbMode());
-        UNIMPLEMENTED();
     }
 
     void CallSVC(u32 swi) override {
@@ -234,20 +242,35 @@ std::shared_ptr<Dynarmic::A32::Jit> ARM_Dynarmic_32::MakeJit(Common::PageTable*
 
 void ARM_Dynarmic_32::Run() {
     while (true) {
-        const auto hr = jit.load()->Run();
+        const auto hr = ShouldStep() ? jit.load()->Step() : jit.load()->Run();
         if (Has(hr, svc_call)) {
             Kernel::Svc::Call(system, svc_swi);
         }
+
+        // Check to see if breakpoint is triggered.
+        // Recheck step condition in case stop is no longer desired.
+        Kernel::KThread* current_thread = system.Kernel().GetCurrentEmuThread();
+        if (Has(hr, breakpoint)) {
+            jit.load()->Regs()[15] = breakpoint_pc;
+
+            if (system.GetDebugger().NotifyThreadStopped(current_thread)) {
+                current_thread->RequestSuspend(Kernel::SuspendType::Debug);
+            }
+            break;
+        }
+        if (ShouldStep()) {
+            // When stepping, this should be the only thread running.
+            ASSERT(system.GetDebugger().NotifyThreadStopped(current_thread));
+            current_thread->RequestSuspend(Kernel::SuspendType::Debug);
+            break;
+        }
+
         if (Has(hr, break_loop) || !uses_wall_clock) {
             break;
         }
     }
 }
 
-void ARM_Dynarmic_32::Step() {
-    jit.load()->Step();
-}
-
 ARM_Dynarmic_32::ARM_Dynarmic_32(System& system_, CPUInterrupts& interrupt_handlers_,
                                  bool uses_wall_clock_, ExclusiveMonitor& exclusive_monitor_,
                                  std::size_t core_index_)

src/core/arm/dynarmic/arm_dynarmic_32.h

@@ -42,7 +42,6 @@ public:
     u32 GetPSTATE() const override;
     void SetPSTATE(u32 pstate) override;
     void Run() override;
-    void Step() override;
     VAddr GetTlsAddress() const override;
     void SetTlsAddress(VAddr address) override;
     void SetTPIDR_EL0(u64 value) override;
@@ -95,6 +94,9 @@ private:
 
     // SVC callback
     u32 svc_swi{};
+
+    // Debug restart address
+    u32 breakpoint_pc{};
 };
 
 } // namespace Core

src/core/arm/dynarmic/arm_dynarmic_64.cpp

@@ -15,6 +15,7 @@
 #include "core/arm/dynarmic/arm_exclusive_monitor.h"
 #include "core/core.h"
 #include "core/core_timing.h"
+#include "core/debugger/debugger.h"
 #include "core/hardware_properties.h"
 #include "core/hle/kernel/k_process.h"
 #include "core/hle/kernel/svc.h"
@@ -27,6 +28,7 @@ using namespace Common::Literals;
 
 constexpr Dynarmic::HaltReason break_loop = Dynarmic::HaltReason::UserDefined2;
 constexpr Dynarmic::HaltReason svc_call = Dynarmic::HaltReason::UserDefined3;
+constexpr Dynarmic::HaltReason breakpoint = Dynarmic::HaltReason::UserDefined4;
 
 class DynarmicCallbacks64 : public Dynarmic::A64::UserCallbacks {
 public:
@@ -119,8 +121,13 @@ public:
         case Dynarmic::A64::Exception::SendEventLocal:
         case Dynarmic::A64::Exception::Yield:
             return;
-        case Dynarmic::A64::Exception::Breakpoint:
         default:
+            if (parent.system.DebuggerEnabled()) {
+                parent.breakpoint_pc = pc;
+                parent.jit.load()->HaltExecution(breakpoint);
+                return;
+            }
+
             parent.LogBacktrace();
             ASSERT_MSG(false, "ExceptionRaised(exception = {}, pc = {:08X}, code = {:08X})",
                        static_cast<std::size_t>(exception), pc, MemoryReadCode(pc));
@@ -299,16 +306,31 @@ void ARM_Dynarmic_64::Run() {
         if (Has(hr, svc_call)) {
             Kernel::Svc::Call(system, svc_swi);
         }
+
+        // Check to see if breakpoint is triggered.
+        // Recheck step condition in case stop is no longer desired.
+        Kernel::KThread* current_thread = system.Kernel().GetCurrentEmuThread();
+        if (Has(hr, breakpoint)) {
+            jit.load()->SetPC(breakpoint_pc);
+
+            if (system.GetDebugger().NotifyThreadStopped(current_thread)) {
+                current_thread->RequestSuspend(Kernel::SuspendType::Debug);
+            }
+            break;
+        }
+        if (ShouldStep()) {
+            // When stepping, this should be the only thread running.
+            ASSERT(system.GetDebugger().NotifyThreadStopped(current_thread));
+            current_thread->RequestSuspend(Kernel::SuspendType::Debug);
+            break;
+        }
+
         if (Has(hr, break_loop) || !uses_wall_clock) {
             break;
         }
     }
 }
 
-void ARM_Dynarmic_64::Step() {
-    jit.load()->Step();
-}
-
 ARM_Dynarmic_64::ARM_Dynarmic_64(System& system_, CPUInterrupts& interrupt_handlers_,
                                  bool uses_wall_clock_, ExclusiveMonitor& exclusive_monitor_,
                                  std::size_t core_index_)

src/core/arm/dynarmic/arm_dynarmic_64.h

@@ -40,7 +40,6 @@ public:
     u32 GetPSTATE() const override;
     void SetPSTATE(u32 pstate) override;
     void Run() override;
-    void Step() override;
     VAddr GetTlsAddress() const override;
     void SetTlsAddress(VAddr address) override;
     void SetTPIDR_EL0(u64 value) override;
@@ -88,6 +87,9 @@ private:
 
     // SVC callback
     u32 svc_swi{};
+
+    // Debug restart address
+    u64 breakpoint_pc{};
 };
 
 } // namespace Core