Support slots recording for compaction during incremental marking.

src/incremental-marking.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 39 matching lines @@
 
 
 void IncrementalMarking::TearDown() {
   delete marking_deque_memory_;
 }
 
 
 void IncrementalMarking::RecordWriteFromCode(HeapObject* obj,
                                              Object* value,
                                              Isolate* isolate) {
-  isolate->heap()->incremental_marking()->RecordWrite(obj, value);
+  ASSERT(obj->IsHeapObject());
+
+  IncrementalMarking* marking = isolate->heap()->incremental_marking();
+  ASSERT(!marking->is_compacting_);
+  marking->RecordWrite(obj, NULL, value);
 }
 
 
+void IncrementalMarking::RecordWriteForEvacuationFromCode(HeapObject* obj,
+                                                          Object** slot,
+                                                          Isolate* isolate) {
+  IncrementalMarking* marking = isolate->heap()->incremental_marking();
+  ASSERT(marking->is_compacting_);
+  marking->RecordWrite(obj, slot, *slot);
+}
+
+
 class IncrementalMarkingMarkingVisitor : public ObjectVisitor {
  public:
   IncrementalMarkingMarkingVisitor(Heap* heap,
                                    IncrementalMarking* incremental_marking)
       : heap_(heap),
         incremental_marking_(incremental_marking) {
   }
 
   void VisitPointer(Object** p) {
-    MarkObjectByPointer(p);
+    MarkObjectByPointer(p, p);
   }
 
   void VisitPointers(Object** start, Object** end) {
-    for (Object** p = start; p < end; p++) MarkObjectByPointer(p);
+    for (Object** p = start; p < end; p++) MarkObjectByPointer(start, p);
   }
 
  private:
   // Mark object pointed to by p.
-  INLINE(void MarkObjectByPointer(Object** p)) {
+  INLINE(void MarkObjectByPointer(Object** anchor, Object** p)) {
     Object* obj = *p;
     // Since we can be sure that the object is not tagged as a failure we can
     // inline a slightly more efficient tag check here than IsHeapObject() would
     // produce.
     if (obj->NonFailureIsHeapObject()) {
       HeapObject* heap_object = HeapObject::cast(obj);
+
+      heap_->mark_compact_collector()->RecordSlot(anchor, p, obj);
       MarkBit mark_bit = Marking::MarkBitFrom(heap_object);
       if (mark_bit.data_only()) {
         incremental_marking_->MarkBlackOrKeepGrey(mark_bit);
       } else if (Marking::IsWhite(mark_bit)) {
         incremental_marking_->WhiteToGreyAndPush(heap_object, mark_bit);
       }
     }
   }
 
   Heap* heap_;
@@ skipping 173 matching lines @@
 
 bool IncrementalMarking::WorthActivating() {
 #ifndef DEBUG
   static const intptr_t kActivationThreshold = 8 * MB;
 #else
   // TODO(gc) consider setting this to some low level so that some
   // debug tests run with incremental marking and some without.
   static const intptr_t kActivationThreshold = 0;
 #endif
 
-  // TODO(gc) ISOLATES MERGE
   return FLAG_incremental_marking &&
       heap_->PromotedSpaceSize() > kActivationThreshold;
 }
 
 
-static void PatchIncrementalMarkingRecordWriteStubs(bool enable) {
-  NumberDictionary* stubs = HEAP->code_stubs();
+static void PatchIncrementalMarkingRecordWriteStubs(
+    Heap* heap, RecordWriteStub::Mode mode) {
+  NumberDictionary* stubs = heap->code_stubs();
 
   int capacity = stubs->Capacity();
   for (int i = 0; i < capacity; i++) {
     Object* k = stubs->KeyAt(i);
     if (stubs->IsKey(k)) {
       uint32_t key = NumberToUint32(k);
 
       if (CodeStub::MajorKeyFromKey(key) ==
           CodeStub::RecordWrite) {
         Object* e = stubs->ValueAt(i);
         if (e->IsCode()) {
-          RecordWriteStub::Patch(Code::cast(e), enable);
+          RecordWriteStub::Patch(Code::cast(e), mode);
         }
       }
     }
   }
 }
 
 
 void IncrementalMarking::EnsureMarkingDequeIsCommitted() {
   if (marking_deque_memory_ == NULL) {
     marking_deque_memory_ = new VirtualMemory(4 * MB);
@@ skipping 26 matching lines @@
 
   heap_->new_space()->LowerInlineAllocationLimit(kAllocatedThreshold);
 }
 
 
 void IncrementalMarking::StartMarking() {
   if (FLAG_trace_incremental_marking) {
     PrintF("[IncrementalMarking] Start marking\n");
   }
 
+  is_compacting_ = !FLAG_never_compact &&
+      heap_->mark_compact_collector()->StartCompaction();
+
   state_ = MARKING;
 
-  PatchIncrementalMarkingRecordWriteStubs(true);
+  RecordWriteStub::Mode mode = is_compacting_ ?
+      RecordWriteStub::INCREMENTAL_COMPACTION : RecordWriteStub::INCREMENTAL;
+
+  PatchIncrementalMarkingRecordWriteStubs(heap_, mode);
 
   EnsureMarkingDequeIsCommitted();
 
   // Initialize marking stack.
   Address addr = static_cast<Address>(marking_deque_memory_->address());
   int size = marking_deque_memory_->size();
   if (FLAG_force_marking_deque_overflows) size = 64 * kPointerSize;
   marking_deque_.Initialize(addr, addr + size);
 
   // Clear markbits.
@@ skipping 30 matching lines @@
   intptr_t current = marking_deque_.bottom();
   intptr_t mask = marking_deque_.mask();
   intptr_t limit = marking_deque_.top();
   HeapObject** array = marking_deque_.array();
   intptr_t new_top = current;
 
   Map* filler_map = heap_->one_pointer_filler_map();
 
   while (current != limit) {
     HeapObject* obj = array[current];
+    ASSERT(obj->IsHeapObject());
     current = ((current + 1) & mask);
     if (heap_->InNewSpace(obj)) {
       MapWord map_word = obj->map_word();
       if (map_word.IsForwardingAddress()) {
         HeapObject* dest = map_word.ToForwardingAddress();
         array[new_top] = dest;
         new_top = ((new_top + 1) & mask);
         ASSERT(new_top != marking_deque_.bottom());
         ASSERT(Marking::IsGrey(Marking::MarkBitFrom(obj)));
       }
@@ skipping 47 matching lines @@
 
 void IncrementalMarking::Abort() {
   if (IsStopped()) return;
   if (FLAG_trace_incremental_marking) {
     PrintF("[IncrementalMarking] Aborting.\n");
   }
   heap_->new_space()->LowerInlineAllocationLimit(0);
   IncrementalMarking::set_should_hurry(false);
   ResetStepCounters();
   if (IsMarking()) {
-    PatchIncrementalMarkingRecordWriteStubs(false);
+    PatchIncrementalMarkingRecordWriteStubs(heap_,
+                                            RecordWriteStub::STORE_BUFFER_ONLY);
     DeactivateIncrementalWriteBarrier();
   }
   heap_->isolate()->stack_guard()->Continue(GC_REQUEST);
   state_ = STOPPED;
+  is_compacting_ = false;
 }
 
 
 void IncrementalMarking::Finalize() {
   Hurry();
   state_ = STOPPED;
+  is_compacting_ = false;
   heap_->new_space()->LowerInlineAllocationLimit(0);
   IncrementalMarking::set_should_hurry(false);
   ResetStepCounters();
-  PatchIncrementalMarkingRecordWriteStubs(false);
+  PatchIncrementalMarkingRecordWriteStubs(heap_,
+                                          RecordWriteStub::STORE_BUFFER_ONLY);
   DeactivateIncrementalWriteBarrier();
   ASSERT(marking_deque_.IsEmpty());
   heap_->isolate()->stack_guard()->Continue(GC_REQUEST);
 }
 
 
 void IncrementalMarking::MarkingComplete() {
   state_ = COMPLETE;
   // We will set the stack guard to request a GC now.  This will mean the rest
   // of the GC gets performed as soon as possible (we can't do a GC here in a
   // record-write context).  If a few things get allocated between now and then
   // that shouldn't make us do a scavenge and keep being incremental, so we set
   // the should-hurry flag to indicate that there can't be much work left to do.
   set_should_hurry(true);
   if (FLAG_trace_incremental_marking) {
     PrintF("[IncrementalMarking] Complete (normal).\n");
   }
-  // TODO(gc) ISOLATES
-  ISOLATE->stack_guard()->RequestGC();
+  heap_->isolate()->stack_guard()->RequestGC();
 }
 
 
 void IncrementalMarking::Step(intptr_t allocated_bytes) {
   if (heap_->gc_state() != Heap::NOT_IN_GC) return;
   if (!FLAG_incremental_marking) return;
   if (!FLAG_incremental_marking_steps) return;
 
   allocated_ += allocated_bytes;
 
@@ skipping 54 matching lines @@
   if (FLAG_trace_incremental_marking || FLAG_trace_gc) {
     double end = OS::TimeCurrentMillis();
     double delta = (end - start);
     steps_took_ += delta;
     steps_took_since_last_gc_ += delta;
   }
 }
 
 
 } }  // namespace v8::internal