cpu: Make accesses to comInstEventQueue indirect through methods.

This lets us move the event queue itself around, or change how those
services are provided.

Change-Id: Ie36665b353cf9788968f253cf281a854a6eff4f4
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22107
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/cpu/base.hh

@@ -465,6 +465,31 @@ class BaseCPU : public ClockedObject
      */
     uint64_t getCurrentInstCount(ThreadID tid);
 
+    Tick
+    nextInstEventCount(ThreadID tid)
+    {
+        return comInstEventQueue[tid]->empty() ?
+            MaxTick : comInstEventQueue[tid]->nextTick();
+    }
+
+    void
+    serviceInstCountEvents(ThreadID tid, Tick count)
+    {
+        comInstEventQueue[tid]->serviceEvents(count);
+    }
+
+    void
+    scheduleInstCountEvent(ThreadID tid, Event *event, Tick count)
+    {
+        comInstEventQueue[tid]->schedule(event, count);
+    }
+
+    void
+    descheduleInstCountEvent(ThreadID tid, Event *event)
+    {
+        comInstEventQueue[tid]->deschedule(event);
+    }
+
   public:
     /**
      * @{