Experimenting with xdb API, starting on compare tool.

src/alloy/backend/ivm/ivm_intcode.cc

@@ -249,7 +249,6 @@ int Translate_SOURCE_OFFSET(TranslationContext& ctx, Instr* i) {
 
 // TODO(benvanik): dispatch of register forms.
 uint32_t IntCode_TRACE_SOURCE(IntCodeState& ics, const IntCode* i) {
-  // TODO(benvanik): append to active trace writer.
   uint64_t trace_base = ics.thread_state->memory()->trace_base();
   if (trace_base) {
     auto ev = xdb::protocol::InstrEvent::Append(trace_base);
@@ -323,7 +322,7 @@ uint32_t IntCode_TRAP(IntCodeState& ics, const IntCode* i) {
   switch (i->flags) {
     case 20:
       // 0x0FE00014 is a 'debug print' where r3 = buffer r4 = length
-      break;
+      return IA_NEXT;
     case 22:
       // Always trap?
       break;

src/alloy/delegate.h

@@ -20,6 +20,9 @@ namespace alloy {
 
 // TODO(benvanik): go lockfree, and don't hold the lock while emitting.
 
+template <typename T>
+class Delegate;
+
 template <typename T>
 class Delegate {
  public:
@@ -30,16 +33,6 @@ class Delegate {
     listeners_.push_back(listener);
   }
 
-  void RemoveListener(Listener const& listener) {
-    std::lock_guard<std::mutex> guard(lock_);
-    for (auto it = listeners_.begin(); it != listeners_.end(); ++it) {
-      if (it == listener) {
-        listeners_.erase(it);
-        break;
-      }
-    }
-  }
-
   void RemoveAllListeners() {
     std::lock_guard<std::mutex> guard(lock_);
     listeners_.clear();
@@ -57,6 +50,33 @@ class Delegate {
   std::vector<Listener> listeners_;
 };
 
+template <>
+class Delegate<void> {
+ public:
+  typedef std::function<void()> Listener;
+
+  void AddListener(Listener const& listener) {
+    std::lock_guard<std::mutex> guard(lock_);
+    listeners_.push_back(listener);
+  }
+
+  void RemoveAllListeners() {
+    std::lock_guard<std::mutex> guard(lock_);
+    listeners_.clear();
+  }
+
+  void operator()() {
+    std::lock_guard<std::mutex> guard(lock_);
+    for (auto& listener : listeners_) {
+      listener();
+    }
+  }
+
+ private:
+  std::mutex lock_;
+  std::vector<Listener> listeners_;
+};
+
 }  // namespace alloy
 
 #endif  // ALLOY_DELEGATE_H_