Fix wrong DCHECK in Heap::FindAllocationMemento where bump pointer overflow points to the currently…

src/heap/heap-inl.h

 // 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.
 
 #ifndef V8_HEAP_HEAP_INL_H_
 #define V8_HEAP_HEAP_INL_H_
 
 #include <cmath>
 
 #include "src/base/platform/platform.h"
@@ skipping 434 matching lines @@
   // object of at least word size (the header map word) following it, so
   // suffices to compare ptr and top here. Note that technically we do not have
   // to compare with the current top pointer of the from space page during GC,
   // since we always install filler objects above the top pointer of a from
   // space page when performing a garbage collection. However, always performing
   // the test makes it possible to have a single, unified version of
   // FindAllocationMemento that is used both by the GC and the mutator.
   Address top = NewSpaceTop();
   DCHECK(memento_address == top ||
          memento_address + HeapObject::kHeaderSize <= top ||
-         !NewSpacePage::OnSamePage(memento_address, top));
+         !NewSpacePage::OnSamePage(memento_address, top - 1));
   if (memento_address == top) return NULL;
 
   AllocationMemento* memento = AllocationMemento::cast(candidate);
   if (!memento->IsValid()) return NULL;
   return memento;
 }
 
 
 void Heap::UpdateAllocationSiteFeedback(HeapObject* object,
                                         ScratchpadSlotMode mode) {
@@ skipping 216 matching lines @@
 
 void VerifySmisVisitor::VisitPointers(Object** start, Object** end) {
   for (Object** current = start; current < end; current++) {
     CHECK((*current)->IsSmi());
   }
 }
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_HEAP_INL_H_