MSan: disable zapping of freelist entries.

third_party/WebKit/Source/platform/heap/HeapPage.cpp

 /*
  * Copyright (C) 2013 Google Inc. 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
@@ skipping 889 matching lines @@
         ASSERT(size >= sizeof(HeapObjectHeader));
         // Free list encode the size to mark the lost memory as freelist memory.
         new (NotNull, address) HeapObjectHeader(size, gcInfoIndexForFreeListHeader);
 
         ASAN_POISON_MEMORY_REGION(address, size);
         // This memory gets lost. Sweeping can reclaim it.
         return;
     }
     entry = new (NotNull, address) FreeListEntry(size);
 
-#if ENABLE(ASSERT) || defined(LEAK_SANITIZER) || defined(ADDRESS_SANITIZER)
+#if (ENABLE(ASSERT) || defined(LEAK_SANITIZER) || defined(ADDRESS_SANITIZER)) && !defined(MEMORY_SANITIZER)
     // The following logic delays reusing free lists for (at least) one GC
     // cycle or coalescing. This is helpful to detect use-after-free errors
     // that could be caused by lazy sweeping etc.
     size_t allowedCount = 0;
     size_t forbiddenCount = 0;
     for (size_t i = sizeof(FreeListEntry); i < size; i++) {
         if (address[i] == reuseAllowedZapValue) {
             allowedCount++;
         } else if (address[i] == reuseForbiddenZapValue) {
             forbiddenCount++;
@@ skipping 41 matching lines @@
     // region to the free list and reuse it for another object.
 #endif
     ASAN_POISON_MEMORY_REGION(address, size);
 
     int index = bucketIndexForSize(size);
     entry->link(&m_freeLists[index]);
     if (index > m_biggestFreeListIndex)
         m_biggestFreeListIndex = index;
 }
 
-#if ENABLE(ASSERT) || defined(LEAK_SANITIZER) || defined(ADDRESS_SANITIZER) || defined(MEMORY_SANITIZER)
+#if (ENABLE(ASSERT) || defined(LEAK_SANITIZER) || defined(ADDRESS_SANITIZER)) && !defined(MEMORY_SANITIZER)
 NO_SANITIZE_ADDRESS
-NO_SANITIZE_MEMORY
 void NEVER_INLINE FreeList::zapFreedMemory(Address address, size_t size)
 {
     for (size_t i = 0; i < size; i++) {
         // See the comment in addToFreeList().
         if (address[i] != reuseAllowedZapValue)
             address[i] = reuseForbiddenZapValue;
     }
 }
 
 void NEVER_INLINE FreeList::checkFreedMemoryIsZapped(Address address, size_t size)
@@ skipping 576 matching lines @@
 
     m_hasEntries = true;
     size_t index = hash(address);
     ASSERT(!(index & 1));
     Address cachePage = roundToBlinkPageStart(address);
     m_entries[index + 1] = m_entries[index];
     m_entries[index] = cachePage;
 }
 
 } // namespace blink