[heap] Exclude the owner of the linear allocation area from evacuation.

test/cctest/heap/heap-utils.cc

 // Copyright 2016 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 "test/cctest/heap/heap-utils.h"
 
 #include "src/factory.h"
 #include "src/heap/heap-inl.h"
 #include "src/heap/incremental-marking.h"
 #include "src/heap/mark-compact.h"
@@ skipping 175 matching lines @@
   }
 }
 
 void GcAndSweep(Heap* heap, AllocationSpace space) {
   heap->CollectGarbage(space, GarbageCollectionReason::kTesting);
   if (heap->mark_compact_collector()->sweeping_in_progress()) {
     heap->mark_compact_collector()->EnsureSweepingCompleted();
   }
 }
 
+void ForceEvacuationCandidate(Page* page) {
+  CHECK(FLAG_manual_evacuation_candidates_selection);
+  page->SetFlag(MemoryChunk::FORCE_EVACUATION_CANDIDATE_FOR_TESTING);
+  PagedSpace* space = static_cast<PagedSpace*>(page->owner());
+  Address top = space->top();
+  Address limit = space->limit();
+  if (top < limit && Page::FromAllocationAreaAddress(top) == page) {
+    // Create filler object to keep page iterable if it was iterable.
+    int remaining = static_cast<int>(limit - top);
+    space->heap()->CreateFillerObjectAt(top, remaining,
+                                        ClearRecordedSlots::kNo);
+    space->SetTopAndLimit(nullptr, nullptr);
+  }
+}
+
 }  // namespace heap
 }  // namespace internal
 }  // namespace v8