Qt: Cache CPU register values

That way they don't update while running.

src/core/cpu_core.cpp

@@ -825,7 +825,6 @@ const std::array<CPU::DebuggerRegisterListEntry, CPU::NUM_DEBUGGER_REGISTER_LIST
                                     {"hi", &CPU::g_state.regs.hi},
                                     {"lo", &CPU::g_state.regs.lo},
                                     {"pc", &CPU::g_state.pc},
-                                    {"npc", &CPU::g_state.npc},
 
                                     {"COP0_SR", &CPU::g_state.cop0_regs.sr.bits},
                                     {"COP0_CAUSE", &CPU::g_state.cop0_regs.cause.bits},

src/core/cpu_core.h

@@ -227,7 +227,7 @@ struct DebuggerRegisterListEntry
   u32* value_ptr;
 };
 
-static constexpr u32 NUM_DEBUGGER_REGISTER_LIST_ENTRIES = 104;
+static constexpr u32 NUM_DEBUGGER_REGISTER_LIST_ENTRIES = 103;
 extern const std::array<DebuggerRegisterListEntry, NUM_DEBUGGER_REGISTER_LIST_ENTRIES> g_debugger_register_list;
 
 } // namespace CPU

src/duckstation-qt/debuggermodels.cpp

@@ -333,11 +333,11 @@ QVariant DebuggerRegistersModel::data(const QModelIndex& index, int role /*= Qt:
     {
       if (role == Qt::DisplayRole)
       {
-        return QString::asprintf("0x%08X", *CPU::g_debugger_register_list[reg_index].value_ptr);
+        return QString::asprintf("0x%08X", m_reg_values[reg_index]);
       }
       else if (role == Qt::ForegroundRole)
       {
-        if (*CPU::g_debugger_register_list[reg_index].value_ptr != m_old_reg_values[reg_index])
+        if (m_reg_values[reg_index] != m_old_reg_values[reg_index])
           return QColor(255, 50, 50);
       }
     }
@@ -370,16 +370,19 @@ QVariant DebuggerRegistersModel::headerData(int section, Qt::Orientation orienta
   }
 }
 
-void DebuggerRegistersModel::invalidateView()
+void DebuggerRegistersModel::updateValues()
 {
   beginResetModel();
+
+  for (u32 i = 0; i < CPU::NUM_DEBUGGER_REGISTER_LIST_ENTRIES; i++)
+    m_reg_values[i] = *CPU::g_debugger_register_list[i].value_ptr;
+
   endResetModel();
 }
 
 void DebuggerRegistersModel::saveCurrentValues()
 {
-  for (u32 i = 0; i < static_cast<u32>(CPU::Reg::count); i++)
-    m_old_reg_values[i] = CPU::g_state.regs.r[i];
+  m_old_reg_values = m_reg_values;
 }
 
 DebuggerStackModel::DebuggerStackModel(QObject* parent /*= nullptr*/) : QAbstractListModel(parent)

src/duckstation-qt/debuggermodels.h

@@ -64,11 +64,12 @@ public:
   virtual QVariant data(const QModelIndex& index, int role = Qt::DisplayRole) const override;
   virtual QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override;
 
-  void invalidateView();
+  void updateValues();
   void saveCurrentValues();
 
 private:
-  u32 m_old_reg_values[CPU::NUM_DEBUGGER_REGISTER_LIST_ENTRIES] = {};
+  std::array<u32 ,CPU::NUM_DEBUGGER_REGISTER_LIST_ENTRIES> m_reg_values = {};
+  std::array<u32, CPU::NUM_DEBUGGER_REGISTER_LIST_ENTRIES> m_old_reg_values = {};
 };
 
 class DebuggerStackModel : public QAbstractListModel

src/duckstation-qt/debuggerwindow.cpp

@@ -66,7 +66,7 @@ void DebuggerWindow::onDebuggerMessageReported(const QString& message)
 
 void DebuggerWindow::refreshAll()
 {
-  m_registers_model->invalidateView();
+  m_registers_model->updateValues();
   m_stack_model->invalidateView();
   m_ui.memoryView->repaint();
 
@@ -196,7 +196,6 @@ void DebuggerWindow::onStepIntoActionTriggered()
   Assert(System::IsPaused());
   m_registers_model->saveCurrentValues();
   g_emu_thread->singleStepCPU();
-  refreshAll();
 }
 
 void DebuggerWindow::onStepOverActionTriggered()