[heap] Add more left and right trimming test cases for black areas.

BUG=

Review-Url: https://codereview.chromium.org/2185383002
Cr-Commit-Position: refs/heads/master@{#38218}

test/cctest/heap/test-heap.cc

@@ -6823,6 +6823,127 @@ TEST(LeftTrimFixedArrayInBlackArea) {
   heap::GcAndSweep(heap, OLD_SPACE);
 }
 
+TEST(ContinuousLeftTrimFixedArrayInBlackArea) {
+  FLAG_black_allocation = true;
+  CcTest::InitializeVM();
+  v8::HandleScope scope(CcTest::isolate());
+  Heap* heap = CcTest::heap();
+  Isolate* isolate = heap->isolate();
+  heap->CollectAllGarbage();
+
+  i::MarkCompactCollector* collector = heap->mark_compact_collector();
+  i::IncrementalMarking* marking = heap->incremental_marking();
+  if (collector->sweeping_in_progress()) {
+    collector->EnsureSweepingCompleted();
+  }
+  CHECK(marking->IsMarking() || marking->IsStopped());
+  if (marking->IsStopped()) {
+    heap->StartIncrementalMarking();
+  }
+  CHECK(marking->IsMarking());
+  marking->StartBlackAllocationForTesting();
+
+  // Ensure that we allocate a new page, set up a bump pointer area, and
+  // perform the allocation in a black area.
+  heap::SimulateFullSpace(heap->old_space());
+  isolate->factory()->NewFixedArray(10, TENURED);
+
+  // Allocate the fixed array that will be trimmed later.
+  Handle<FixedArray> array = isolate->factory()->NewFixedArray(100, TENURED);
+  Address start_address = array->address();
+  Address end_address = start_address + array->Size();
+  Page* page = Page::FromAddress(start_address);
+  CHECK(Marking::IsBlack(ObjectMarking::MarkBitFrom(*array)));
+  CHECK(page->markbits()->AllBitsSetInRange(
+      page->AddressToMarkbitIndex(start_address),
+      page->AddressToMarkbitIndex(end_address)));
+  CHECK(heap->old_space()->Contains(*array));
+
+  FixedArrayBase* previous = *array;
+  FixedArrayBase* trimmed;
+
+  // First trim in one word steps.
+  for (int i = 0; i < 10; i++) {
+    trimmed = heap->LeftTrimFixedArray(previous, 1);
+    HeapObject* filler = HeapObject::FromAddress(previous->address());
+    CHECK(filler->IsFiller());
+    CHECK(Marking::IsBlack(ObjectMarking::MarkBitFrom(trimmed)));
+    CHECK(Marking::IsImpossible(ObjectMarking::MarkBitFrom(previous)));
+    previous = trimmed;
+  }
+
+  // Then trim in two and three word steps.
+  for (int i = 2; i <= 3; i++) {
+    for (int j = 0; j < 10; j++) {
+      trimmed = heap->LeftTrimFixedArray(previous, i);
+      HeapObject* filler = HeapObject::FromAddress(previous->address());
+      CHECK(filler->IsFiller());
+      CHECK(Marking::IsBlack(ObjectMarking::MarkBitFrom(trimmed)));
+      CHECK(Marking::IsWhite(ObjectMarking::MarkBitFrom(previous)));
+      previous = trimmed;
+    }
+  }
+
+  heap::GcAndSweep(heap, OLD_SPACE);
+}
+
+TEST(ContinuousRightTrimFixedArrayInBlackArea) {
+  FLAG_black_allocation = true;
+  CcTest::InitializeVM();
+  v8::HandleScope scope(CcTest::isolate());
+  Heap* heap = CcTest::heap();
+  Isolate* isolate = heap->isolate();
+  heap->CollectAllGarbage();
+
+  i::MarkCompactCollector* collector = heap->mark_compact_collector();
+  i::IncrementalMarking* marking = heap->incremental_marking();
+  if (collector->sweeping_in_progress()) {
+    collector->EnsureSweepingCompleted();
+  }
+  CHECK(marking->IsMarking() || marking->IsStopped());
+  if (marking->IsStopped()) {
+    heap->StartIncrementalMarking();
+  }
+  CHECK(marking->IsMarking());
+  marking->StartBlackAllocationForTesting();
+
+  // Ensure that we allocate a new page, set up a bump pointer area, and
+  // perform the allocation in a black area.
+  heap::SimulateFullSpace(heap->old_space());
+  isolate->factory()->NewFixedArray(10, TENURED);
+
+  // Allocate the fixed array that will be trimmed later.
+  Handle<FixedArray> array = isolate->factory()->NewFixedArray(100, TENURED);
+  Address start_address = array->address();
+  Address end_address = start_address + array->Size();
+  Page* page = Page::FromAddress(start_address);
+  CHECK(Marking::IsBlack(ObjectMarking::MarkBitFrom(*array)));
+  CHECK(page->markbits()->AllBitsSetInRange(
+      page->AddressToMarkbitIndex(start_address),
+      page->AddressToMarkbitIndex(end_address)));
+  CHECK(heap->old_space()->Contains(*array));
+
+  // Trim it once by one word to make checking for white marking color uniform.
+  Address previous = end_address - kPointerSize;
+  heap->RightTrimFixedArray<Heap::SEQUENTIAL_TO_SWEEPER>(*array, 1);
+  HeapObject* filler = HeapObject::FromAddress(previous);
+  CHECK(filler->IsFiller());
+  CHECK(Marking::IsImpossible(ObjectMarking::MarkBitFrom(previous)));
+
+  // Trim 10 times by one, two, and three word.
+  for (int i = 1; i <= 3; i++) {
+    for (int j = 0; j < 10; j++) {
+      previous -= kPointerSize * i;
+      heap->RightTrimFixedArray<Heap::SEQUENTIAL_TO_SWEEPER>(*array, i);
+      HeapObject* filler = HeapObject::FromAddress(previous);
+      CHECK(filler->IsFiller());
+      CHECK(Marking::IsWhite(ObjectMarking::MarkBitFrom(previous)));
+    }
+  }
+
+  heap::GcAndSweep(heap, OLD_SPACE);
+}
+
 TEST(Regress618958) {
   CcTest::InitializeVM();
   v8::HandleScope scope(CcTest::isolate());