[heap] Add basic infrastructure for Minor Mark-Compact collector

src/heap/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_H_
 #define V8_HEAP_HEAP_H_
 
 #include <cmath>
 #include <map>
 
@@ skipping 666 matching lines @@
     return true;
 #else
 #ifdef VERIFY_HEAP
     return FLAG_verify_heap;
 #else
     return false;
 #endif
 #endif
   }
 
+  static inline bool IsYoungGenerationCollector(GarbageCollector collector) {
+    return collector == SCAVENGER || collector == MINOR_MARK_COMPACTOR;
+  }
+
+  static inline GarbageCollector YoungGenerationCollector() {
+    return (FLAG_minor_mc) ? MINOR_MARK_COMPACTOR : SCAVENGER;
+  }
+
   V8_EXPORT_PRIVATE static double HeapGrowingFactor(double gc_speed,
                                                     double mutator_speed);
 
   // Copy block of memory from src to dst. Size of block should be aligned
   // by pointer size.
   static inline void CopyBlock(Address dst, Address src, int byte_size);
 
   // Determines a static visitor id based on the given {map} that can then be
   // stored on the map to facilitate fast dispatch for {StaticVisitorBase}.
   static int GetStaticVisitorIdForMap(Map* map);
@@ skipping 1069 matching lines @@
   // Actual GC. ================================================================
   // ===========================================================================
 
   // Code that should be run before and after each GC.  Includes some
   // reporting/verification activities when compiled with DEBUG set.
   void GarbageCollectionPrologue();
   void GarbageCollectionEpilogue();
 
   // Performs a major collection in the whole heap.
   void MarkCompact();
+  // Performs a minor collection of just the young generation.
+  void MinorMarkCompact();
 
   // Code to be run before and after mark-compact.
   void MarkCompactPrologue();
   void MarkCompactEpilogue();
 
   // Performs a minor collection in new generation.
   void Scavenge();
 
   Address DoScavenge(ObjectVisitor* scavenge_visitor, Address new_space_front);
 
@@ skipping 842 matching lines @@
   friend class LargeObjectSpace;
   friend class NewSpace;
   friend class PagedSpace;
   DISALLOW_COPY_AND_ASSIGN(AllocationObserver);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_HEAP_H_