[heap] Minor MC: Add evacuation phase

src/heap/mark-compact.h

Index: src/heap/mark-compact.h
diff --git a/src/heap/mark-compact.h b/src/heap/mark-compact.h
index 5b7217ed74d2ef9439379db2b2278a5349536f84..3da551f009d57a37bd2b7a42b23463deca1a4fba 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -436,6 +436,8 @@ class MarkCompactCollector {
 
   // Performs a global garbage collection.
   void CollectGarbage();
+  // Performs a garbage collection in the young generation.
+  void CollectGarbageInYoungGeneration();
 
   bool StartCompaction();
 
@@ -659,6 +661,7 @@ class MarkCompactCollector {
   // Clear non-live references in weak cells, transition and descriptor arrays,
   // and deoptimize dependent code of non-live maps.
   void ClearNonLiveReferences();
+  void ClearNonLiveReferencesInYoungGeneration();
   void MarkDependentCodeForDeoptimization(DependentCode* list);
   // Find non-live targets of simple transitions in the given list. Clear
   // transitions to non-live targets and if needed trim descriptors arrays.
@@ -699,13 +702,16 @@ class MarkCompactCollector {
 
   void EvacuateNewSpacePrologue();
 
+  template <MarkCompactMode mode>
   void EvacuatePagesInParallel();
 
   // The number of parallel compaction tasks, including the main thread.
   int NumberOfParallelCompactionTasks(int pages, intptr_t live_bytes);
 
+  template <MarkCompactMode mode>
   void EvacuateNewSpaceAndCandidates();
 
+  template <MarkCompactMode mode>
   void UpdatePointersAfterEvacuation();
 
   // Iterates through all live objects on a page using marking information.