[heap] Record pretenuring feedback for moved pages

src/heap/mark-compact.cc

 // 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.
 
 #include "src/heap/mark-compact.h"
 
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/base/sys-info.h"
 #include "src/code-stubs.h"
@@ skipping 1816 matching lines @@
     return allocation;
   }
 
   LocalAllocationBuffer buffer_;
   AllocationSpace space_to_allocate_;
   intptr_t promoted_size_;
   intptr_t semispace_copied_size_;
   base::HashMap* local_pretenuring_feedback_;
 };
 
+template <PageEvacuationMode mode>
 class MarkCompactCollector::EvacuateNewSpacePageVisitor final
     : public MarkCompactCollector::HeapObjectVisitor {
  public:
-  explicit EvacuateNewSpacePageVisitor(Heap* heap)
-      : heap_(heap), promoted_size_(0), semispace_copied_size_(0) {}
+  explicit EvacuateNewSpacePageVisitor(
+      Heap* heap, base::HashMap* local_pretenuring_feedback)
+      : heap_(heap),
+        moved_bytes_(0),
+        local_pretenuring_feedback_(local_pretenuring_feedback) {}
 
-  static void MoveToOldSpace(Page* page, PagedSpace* owner) {
-    page->Unlink();
-    Page* new_page = Page::ConvertNewToOld(page, owner);
-    new_page->SetFlag(Page::PAGE_NEW_OLD_PROMOTION);
-  }
-
-  static void MoveToToSpace(Page* page) {
-    page->heap()->new_space()->MovePageFromSpaceToSpace(page);
-    page->SetFlag(Page::PAGE_NEW_NEW_PROMOTION);
+  static void Move(Page* page, PagedSpace* new_owner = nullptr) {

[Hannes Payer (out of office), 2016/11/10 16:09:46]

I do not need the both the mode and the new_owner. Because a new space pages
stays a new space page, or it moves to old space. Having one is good enough to
tell. I would remove one.

[Michael Lippautz, 2016/11/10 16:20:29]

Done.

+    switch (mode) {
+      case NEW_TO_NEW:
+        DCHECK_NULL(new_owner);
+        page->heap()->new_space()->MovePageFromSpaceToSpace(page);
+        page->SetFlag(Page::PAGE_NEW_NEW_PROMOTION);
+        break;
+      case NEW_TO_OLD: {
+        page->Unlink();
+        Page* new_page = Page::ConvertNewToOld(page, new_owner);
+        new_page->SetFlag(Page::PAGE_NEW_OLD_PROMOTION);
+        break;
+      }
+    }
   }
 
   inline bool Visit(HeapObject* object) {
-    RecordMigratedSlotVisitor visitor(heap_->mark_compact_collector());
-    object->IterateBodyFast(&visitor);
-    promoted_size_ += object->Size();
+    heap_->UpdateAllocationSite<Heap::kCached>(object,
+                                               local_pretenuring_feedback_);
+    if (mode == NEW_TO_OLD) {
+      RecordMigratedSlotVisitor visitor(heap_->mark_compact_collector());
+      object->IterateBodyFast(&visitor);
+    }
     return true;
   }
 
-  intptr_t promoted_size() { return promoted_size_; }
-  intptr_t semispace_copied_size() { return semispace_copied_size_; }
-
-  void account_semispace_copied(intptr_t copied) {
-    semispace_copied_size_ += copied;
-  }
+  intptr_t moved_bytes() { return moved_bytes_; }
+  void account_moved_bytes(intptr_t bytes) { moved_bytes_ += bytes; }
 
  private:
   Heap* heap_;
-  intptr_t promoted_size_;
-  intptr_t semispace_copied_size_;
+  intptr_t moved_bytes_;
+  base::HashMap* local_pretenuring_feedback_;
 };
 
 class MarkCompactCollector::EvacuateOldSpaceVisitor final
     : public MarkCompactCollector::EvacuateVisitorBase {
  public:
   EvacuateOldSpaceVisitor(Heap* heap,
                           CompactionSpaceCollection* compaction_spaces)
       : EvacuateVisitorBase(heap, compaction_spaces) {}
 
   inline bool Visit(HeapObject* object) override {
@@ skipping 1036 matching lines @@
       return FLAG_page_promotion_threshold * Page::kAllocatableMemory / 100;
     return Page::kAllocatableMemory + kPointerSize;
   }
 
   explicit Evacuator(MarkCompactCollector* collector)
       : collector_(collector),
         compaction_spaces_(collector->heap()),
         local_pretenuring_feedback_(kInitialLocalPretenuringFeedbackCapacity),
         new_space_visitor_(collector->heap(), &compaction_spaces_,
                            &local_pretenuring_feedback_),
-        new_space_page_visitor(collector->heap()),
+        new_to_new_page_visitor_(collector->heap(),
+                                 &local_pretenuring_feedback_),
+        new_to_old_page_visitor_(collector->heap(),
+                                 &local_pretenuring_feedback_),
+
         old_space_visitor_(collector->heap(), &compaction_spaces_),
         duration_(0.0),
         bytes_compacted_(0) {}
 
   inline bool EvacuatePage(Page* chunk);
 
   // Merge back locally cached info sequentially. Note that this method needs
   // to be called from the main thread.
   inline void Finalize();
 
@@ skipping 10 matching lines @@
   }
 
   MarkCompactCollector* collector_;
 
   // Locally cached collector data.
   CompactionSpaceCollection compaction_spaces_;
   base::HashMap local_pretenuring_feedback_;
 
   // Visitors for the corresponding spaces.
   EvacuateNewSpaceVisitor new_space_visitor_;
-  EvacuateNewSpacePageVisitor new_space_page_visitor;
+  EvacuateNewSpacePageVisitor<PageEvacuationMode::NEW_TO_NEW>
+      new_to_new_page_visitor_;
+  EvacuateNewSpacePageVisitor<PageEvacuationMode::NEW_TO_OLD>
+      new_to_old_page_visitor_;
   EvacuateOldSpaceVisitor old_space_visitor_;
 
   // Book keeping info.
   double duration_;
   intptr_t bytes_compacted_;
 };
 
 bool MarkCompactCollector::Evacuator::EvacuatePage(Page* page) {
   bool success = false;
   DCHECK(page->SweepingDone());
   int saved_live_bytes = page->LiveBytes();
   double evacuation_time = 0.0;
   Heap* heap = page->heap();
   {
     AlwaysAllocateScope always_allocate(heap->isolate());
     TimedScope timed_scope(&evacuation_time);
     switch (ComputeEvacuationMode(page)) {
       case kObjectsNewToOld:
         success = collector_->VisitLiveObjects(page, &new_space_visitor_,
                                                kClearMarkbits);
+        DCHECK(success);
         ArrayBufferTracker::ProcessBuffers(
             page, ArrayBufferTracker::kUpdateForwardedRemoveOthers);
-        DCHECK(success);
         break;
       case kPageNewToOld:
-        success = collector_->VisitLiveObjects(page, &new_space_page_visitor,
+        success = collector_->VisitLiveObjects(page, &new_to_old_page_visitor_,
                                                kKeepMarking);
+        DCHECK(success);
+        new_to_old_page_visitor_.account_moved_bytes(page->LiveBytes());
         // ArrayBufferTracker will be updated during sweeping.
-        DCHECK(success);
         break;
       case kPageNewToNew:
-        new_space_page_visitor.account_semispace_copied(page->LiveBytes());
+        success = collector_->VisitLiveObjects(page, &new_to_new_page_visitor_,
+                                               kKeepMarking);
+        new_to_new_page_visitor_.account_moved_bytes(page->LiveBytes());
+        DCHECK(success);

[Hannes Payer (out of office), 2016/11/10 16:09:46]

move up DCHECK one line to be in sync with the preceding code.

[Michael Lippautz, 2016/11/10 16:20:29]

Done.

         // ArrayBufferTracker will be updated during sweeping.
-        success = true;
         break;
       case kObjectsOldToOld:
         success = collector_->VisitLiveObjects(page, &old_space_visitor_,
                                                kClearMarkbits);
         if (!success) {
           // Aborted compaction page. We have to record slots here, since we
           // might not have recorded them in first place.
           // Note: We mark the page as aborted here to be able to record slots
           // for code objects in |RecordMigratedSlotVisitor|.
           page->SetFlag(Page::COMPACTION_WAS_ABORTED);
           EvacuateRecordOnlyVisitor record_visitor(collector_->heap());
           success =
               collector_->VisitLiveObjects(page, &record_visitor, kKeepMarking);
           ArrayBufferTracker::ProcessBuffers(
               page, ArrayBufferTracker::kUpdateForwardedKeepOthers);
           DCHECK(success);
           // We need to return failure here to indicate that we want this page
           // added to the sweeper.
           success = false;
         } else {
           ArrayBufferTracker::ProcessBuffers(
               page, ArrayBufferTracker::kUpdateForwardedRemoveOthers);
         }
         break;
-      default:
-        UNREACHABLE();
     }
   }
   ReportCompactionProgress(evacuation_time, saved_live_bytes);
   if (FLAG_trace_evacuation) {
     PrintIsolate(heap->isolate(),
                  "evacuation[%p]: page=%p new_space=%d "
                  "page_evacuation=%d executable=%d contains_age_mark=%d "
                  "live_bytes=%d time=%f\n",
                  static_cast<void*>(this), static_cast<void*>(page),
                  page->InNewSpace(),
                  page->IsFlagSet(Page::PAGE_NEW_OLD_PROMOTION) ||
                      page->IsFlagSet(Page::PAGE_NEW_NEW_PROMOTION),
                  page->IsFlagSet(MemoryChunk::IS_EXECUTABLE),
                  page->Contains(heap->new_space()->age_mark()),
                  saved_live_bytes, evacuation_time);
   }
   return success;
 }
 
 void MarkCompactCollector::Evacuator::Finalize() {
   heap()->old_space()->MergeCompactionSpace(compaction_spaces_.Get(OLD_SPACE));
   heap()->code_space()->MergeCompactionSpace(
       compaction_spaces_.Get(CODE_SPACE));
   heap()->tracer()->AddCompactionEvent(duration_, bytes_compacted_);
   heap()->IncrementPromotedObjectsSize(new_space_visitor_.promoted_size() +
-                                       new_space_page_visitor.promoted_size());
+                                       new_to_old_page_visitor_.moved_bytes());
   heap()->IncrementSemiSpaceCopiedObjectSize(
       new_space_visitor_.semispace_copied_size() +
-      new_space_page_visitor.semispace_copied_size());
+      new_to_new_page_visitor_.moved_bytes());
   heap()->IncrementYoungSurvivorsCounter(
       new_space_visitor_.promoted_size() +
       new_space_visitor_.semispace_copied_size() +
-      new_space_page_visitor.promoted_size() +
-      new_space_page_visitor.semispace_copied_size());
+      new_to_old_page_visitor_.moved_bytes() +
+      new_to_new_page_visitor_.moved_bytes());
   heap()->MergeAllocationSitePretenuringFeedback(local_pretenuring_feedback_);
 }
 
 int MarkCompactCollector::NumberOfParallelCompactionTasks(int pages,
                                                           intptr_t live_bytes) {
   if (!FLAG_parallel_compaction) return 1;
   // Compute the number of needed tasks based on a target compaction time, the
   // profiled compaction speed and marked live memory.
   //
   // The number of parallel compaction tasks is limited by:
@@ skipping 76 matching lines @@
   }
 
   const bool reduce_memory = heap()->ShouldReduceMemory();
   const Address age_mark = heap()->new_space()->age_mark();
   for (Page* page : newspace_evacuation_candidates_) {
     live_bytes += page->LiveBytes();
     if (!reduce_memory && !page->NeverEvacuate() &&
         (page->LiveBytes() > Evacuator::PageEvacuationThreshold()) &&
         !page->Contains(age_mark)) {
       if (page->IsFlagSet(MemoryChunk::NEW_SPACE_BELOW_AGE_MARK)) {
-        EvacuateNewSpacePageVisitor::MoveToOldSpace(page, heap()->old_space());
+        EvacuateNewSpacePageVisitor<NEW_TO_OLD>::Move(page,
+                                                      heap()->old_space());
       } else {
-        EvacuateNewSpacePageVisitor::MoveToToSpace(page);
+        EvacuateNewSpacePageVisitor<NEW_TO_NEW>::Move(page);
       }
     }
 
     job.AddPage(page, &abandoned_pages);
   }
   DCHECK_GE(job.NumberOfPages(), 1);
 
   // Used for trace summary.
   double compaction_speed = 0;
   if (FLAG_trace_evacuation) {
@@ skipping 758 matching lines @@
       // The target is always in old space, we don't have to record the slot in
       // the old-to-new remembered set.
       DCHECK(!heap()->InNewSpace(target));
       RecordRelocSlot(host, &rinfo, target);
     }
   }
 }
 
 }  // namespace internal
 }  // namespace v8