Remove sequential sweeping mode and perform lazy sweeping when no sweeper threads are active.

src/mark-compact.h

Index: src/mark-compact.h
diff --git a/src/mark-compact.h b/src/mark-compact.h
index bcbc05606190cb7efb149e298dfd3893ef8ddf28..329ebff50cab40be7d517f9c2fcc1210a00a72d0 100644
--- a/src/mark-compact.h
+++ b/src/mark-compact.h
@@ -570,7 +570,6 @@ class MarkCompactCollector {
   void EnableCodeFlushing(bool enable);
 
   enum SweeperType {
-    CONSERVATIVE,
     PARALLEL_CONSERVATIVE,
     CONCURRENT_CONSERVATIVE,
     PRECISE
@@ -673,10 +672,8 @@ class MarkCompactCollector {
 
   bool AreSweeperThreadsActivated();
 
-  // If a paged space is passed in, this method checks if the given space is
-  // swept concurrently. Otherwise, this method checks if concurrent sweeping
-  // is in progress right now on any space.
-  bool IsConcurrentSweepingInProgress(PagedSpace* space = NULL);
+  // Checks if sweeping is in progress right now on any space.
+  bool sweeping_pending() { return sweeping_pending_; }

[Jarin, 2014/07/11 07:40:52]

Nit: so why is not this called IsSweepingInProgress (or some such)?

[Hannes Payer (out of office), 2014/07/11 09:36:13]

It is a true getter now. Anyhow, I renamed the variable to
sweeping_in_progress_.

 
   void set_sequential_sweeping(bool sequential_sweeping) {
     sequential_sweeping_ = sequential_sweeping;