GDBJIT: Remove codes when they are garbage collected.

src/mark-compact.cc

Index: src/mark-compact.cc
===================================================================
--- src/mark-compact.cc	(revision 15370)
+++ src/mark-compact.cc	(working copy)
@@ -3117,6 +3117,11 @@
       Address free_end = object_address + offsets[live_index++] * kPointerSize;
       if (free_end != free_start) {
         space->Free(free_start, static_cast<int>(free_end - free_start));
+#ifdef ENABLE_GDB_JIT_INTERFACE

[Michael Starzinger, 2013/07/03 11:18:50]

I am not particularly fond of plastering GDBJIT entry hooks throughout the GC.
In the long run this should be unified with the generic eventing mechanism
(v8.h:JitCodeEvent) so that each user of that mechanism observes the same
events. GDBJIT should hence hook into Logger::IssueCodeMovedEvent and friends.
But this is a larger cleanup that we can follup-up upon and I am fine with
landing this as a temporary fix.

+        if (FLAG_gdbjit && space->identity() == CODE_SPACE) {
+          GDBJITInterface::RemoveCodeRange(free_start, free_end);
+        }
+#endif
       }
       HeapObject* live_object = HeapObject::FromAddress(free_end);
       ASSERT(Marking::IsBlack(Marking::MarkBitFrom(live_object)));
@@ -3143,6 +3148,11 @@
   }
   if (free_start != p->area_end()) {
     space->Free(free_start, static_cast<int>(p->area_end() - free_start));
+#ifdef ENABLE_GDB_JIT_INTERFACE
+    if (FLAG_gdbjit && space->identity() == CODE_SPACE) {
+      GDBJITInterface::RemoveCodeRange(free_start, p->area_end());
+    }
+#endif
   }
   p->ResetLiveBytes();
   if (FLAG_print_cumulative_gc_stat) {