[heap] Move slots buffer into a separate file.

test/cctest/test-slots-buffer.cc

+// Copyright 2015 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/slots-buffer.h"
+#include "test/cctest/cctest.h"
+
+namespace v8 {
+namespace internal {
+
+TEST(SlotsBufferObjectSlotsRemoval) {
+  CcTest::InitializeVM();
+  v8::HandleScope scope(CcTest::isolate());
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+  Factory* factory = isolate->factory();
+
+  SlotsBuffer* buffer = new SlotsBuffer(NULL);
+  void* fake_object[1];
+
+  Handle<FixedArray> array = factory->NewFixedArray(2, TENURED);
+  CHECK(heap->old_space()->Contains(*array));
+  array->set(0, reinterpret_cast<Object*>(fake_object), SKIP_WRITE_BARRIER);
+
+  // Firstly, let's test the regular slots buffer entry.
+  buffer->Add(HeapObject::RawField(*array, FixedArray::kHeaderSize));
+  CHECK(reinterpret_cast<void*>(buffer->Get(0)) ==
+        HeapObject::RawField(*array, FixedArray::kHeaderSize));
+  SlotsBuffer::RemoveObjectSlots(CcTest::i_isolate()->heap(), buffer,
+                                 array->address(),
+                                 array->address() + array->Size());
+  CHECK(reinterpret_cast<void*>(buffer->Get(0)) ==
+        HeapObject::RawField(heap->empty_fixed_array(),
+                             FixedArrayBase::kLengthOffset));
+
+  // Secondly, let's test the typed slots buffer entry.
+  SlotsBuffer::AddTo(NULL, &buffer, SlotsBuffer::EMBEDDED_OBJECT_SLOT,
+                     array->address() + FixedArray::kHeaderSize,
+                     SlotsBuffer::FAIL_ON_OVERFLOW);
+  CHECK(reinterpret_cast<void*>(buffer->Get(1)) ==
+        reinterpret_cast<Object**>(SlotsBuffer::EMBEDDED_OBJECT_SLOT));
+  CHECK(reinterpret_cast<void*>(buffer->Get(2)) ==
+        HeapObject::RawField(*array, FixedArray::kHeaderSize));
+  SlotsBuffer::RemoveObjectSlots(CcTest::i_isolate()->heap(), buffer,
+                                 array->address(),
+                                 array->address() + array->Size());
+  CHECK(reinterpret_cast<void*>(buffer->Get(1)) ==
+        HeapObject::RawField(heap->empty_fixed_array(),
+                             FixedArrayBase::kLengthOffset));
+  CHECK(reinterpret_cast<void*>(buffer->Get(2)) ==
+        HeapObject::RawField(heap->empty_fixed_array(),
+                             FixedArrayBase::kLengthOffset));
+  delete buffer;
+}
+
+
+TEST(FilterInvalidSlotsBufferEntries) {
+  FLAG_manual_evacuation_candidates_selection = true;
+  CcTest::InitializeVM();
+  v8::HandleScope scope(CcTest::isolate());
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+  Factory* factory = isolate->factory();
+  SlotsBuffer* buffer = new SlotsBuffer(NULL);
+
+  // Set up a fake black object that will contain a recorded SMI, a recorded
+  // pointer to a new space object, and a recorded pointer to a non-evacuation
+  // candidate object. These object should be filtered out. Additionally,
+  // we point to an evacuation candidate object which should not be filtered
+  // out.
+
+  // Create fake object and mark it black.
+  Handle<FixedArray> fake_object = factory->NewFixedArray(23, TENURED);
+  MarkBit mark_bit = Marking::MarkBitFrom(*fake_object);
+  Marking::MarkBlack(mark_bit);
+
+  // Write a SMI into field one and record its address;
+  Object** field_smi = fake_object->RawFieldOfElementAt(0);
+  *field_smi = Smi::FromInt(100);
+  buffer->Add(field_smi);
+
+  // Write a new space reference into field 2 and record its address;
+  Handle<FixedArray> new_space_object = factory->NewFixedArray(23);
+  mark_bit = Marking::MarkBitFrom(*new_space_object);
+  Marking::MarkBlack(mark_bit);
+  Object** field_new_space = fake_object->RawFieldOfElementAt(1);
+  *field_new_space = *new_space_object;
+  buffer->Add(field_new_space);
+
+  // Write an old space reference into field 3 which points to an object not on
+  // an evacuation candidate.
+  Handle<FixedArray> old_space_object_non_evacuation =
+      factory->NewFixedArray(23, TENURED);
+  mark_bit = Marking::MarkBitFrom(*old_space_object_non_evacuation);
+  Marking::MarkBlack(mark_bit);
+  Object** field_old_space_object_non_evacuation =
+      fake_object->RawFieldOfElementAt(2);
+  *field_old_space_object_non_evacuation = *old_space_object_non_evacuation;
+  buffer->Add(field_old_space_object_non_evacuation);
+
+  // Write an old space reference into field 4 which points to an object on an
+  // evacuation candidate.
+  SimulateFullSpace(heap->old_space());
+  Handle<FixedArray> valid_object =
+      isolate->factory()->NewFixedArray(23, TENURED);
+  Page* page = Page::FromAddress(valid_object->address());
+  page->SetFlag(MemoryChunk::EVACUATION_CANDIDATE);
+  Object** valid_field = fake_object->RawFieldOfElementAt(3);
+  *valid_field = *valid_object;
+  buffer->Add(valid_field);
+
+  SlotsBuffer::RemoveInvalidSlots(heap, buffer);
+  Object** kRemovedEntry = HeapObject::RawField(heap->empty_fixed_array(),
+                                                FixedArrayBase::kLengthOffset);
+  CHECK_EQ(buffer->Get(0), kRemovedEntry);
+  CHECK_EQ(buffer->Get(1), kRemovedEntry);
+  CHECK_EQ(buffer->Get(2), kRemovedEntry);
+  CHECK_EQ(buffer->Get(3), valid_field);
+
+  // Clean-up to make verify heap happy.
+  mark_bit = Marking::MarkBitFrom(*fake_object);
+  Marking::MarkWhite(mark_bit);
+  mark_bit = Marking::MarkBitFrom(*new_space_object);
+  Marking::MarkWhite(mark_bit);
+  mark_bit = Marking::MarkBitFrom(*old_space_object_non_evacuation);
+  Marking::MarkWhite(mark_bit);
+
+  delete buffer;
+}
+
+}  // namespace internal
+}  // namespace v8