Make progress in incremental marking if scavenge is delaying mark-sweep.

src/incremental-marking.h

Index: src/incremental-marking.h
diff --git a/src/incremental-marking.h b/src/incremental-marking.h
index 4f8fa6b1275b0995a919503972c6ed8b360daaa5..1110d5336009d9e778333b8191c10132b31c1df3 100644
--- a/src/incremental-marking.h
+++ b/src/incremental-marking.h
@@ -46,6 +46,11 @@ class IncrementalMarking {
     COMPLETE
   };
 
+  enum Finalizer {

[Michael Starzinger, 2012/04/02 09:01:46]

The name "finalizer" feels wrong. Can we change this to something like ...
enum CompletionAction {
  NO_COMPLETION_ACTION,
  GC_VIA_STACK_GUARD
};

[ulan, 2012/04/02 09:42:24]

Done.

+    GC_VIA_STACK_GUARD,
+    NO_GC_VIA_STACK_GUARD
+  };
+
   explicit IncrementalMarking(Heap* heap);
 
   void TearDown();
@@ -82,7 +87,7 @@ class IncrementalMarking {
 
   void Abort();
 
-  void MarkingComplete();
+  void MarkingComplete(Finalizer finalizer);
 
   // It's hard to know how much work the incremental marker should do to make
   // progress in the face of the mutator creating new work for it.  We start
@@ -105,7 +110,7 @@ class IncrementalMarking {
     Step(allocated * kFastMarking / kInitialAllocationMarkingFactor);
   }
 
-  void Step(intptr_t allocated);
+  void Step(intptr_t allocated, Finalizer finalizer = GC_VIA_STACK_GUARD);

[Michael Starzinger, 2012/04/02 09:01:46]

There are only three other call-sites, could we get along without a default
argument?

[ulan, 2012/04/02 09:42:24]

Done.

 
   inline void RestartIfNotMarking() {
     if (state_ == COMPLETE) {