[Lldb-commits] [lldb] [lldb] Introduce internal stop hooks (PR #164506)

[Julian Lettner via lldb-commits]

================
@@ -3098,6 +3107,23 @@ void Target::SetAllStopHooksActiveState(bool active_state) {
   }
 }
 
+// FIXME:  Ideally we would like to return a `const &` (const reference) instead
----------------
yln wrote:

```
typedef std::map<lldb::user_id_t, StopHookSP> StopHookCollection;
StopHookCollection m_stop_hooks;
```
Iteration order of `std::map` is defined by its keys (ascending).

Previously, we were *also* using `std::map` iteration order, just in a really convoluted/inefficient way:
```
size_t GetNumStopHooks() const { return m_stop_hooks.size(); }

StopHookSP GetStopHookAtIndex(size_t index) {  // <<< this is 0-based index, not the "user ID"
  if (index >= GetNumStopHooks())
    return StopHookSP();
  StopHookCollection::iterator pos = m_stop_hooks.begin();   // <<< std::map iterator

  while (index > 0) {
    pos++;
    index--;
  }
  return (*pos).second;
}

// Call sites:
  size_t num_hooks = target.GetNumStopHooks(); 
  for (size_t i = 0; i < num_hooks; i++) {
    Target::StopHookSP hook = target.GetStopHookAtIndex(i);
    ...
  }
```



https://github.com/llvm/llvm-project/pull/164506