Strengthen a few assertions and add zapping of allocated...

src/spaces.cc

 // Copyright 2006-2008 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 339 matching lines @@
                                          Executability executable) {
   if (size_ + static_cast<int>(requested) > capacity_) return NULL;
   void* mem;
   if (executable == EXECUTABLE  && CodeRange::exists()) {
     mem = CodeRange::AllocateRawMemory(requested, allocated);
   } else {
     mem = OS::Allocate(requested, allocated, (executable == EXECUTABLE));
   }
   int alloced = static_cast<int>(*allocated);
   size_ += alloced;
+#ifdef DEBUG
+  // Is this the problematic one?

[Kevin Millikin (Chromium), 2010/01/28 08:38:02]

I'm not sure this comment adds anything.

+  ZapBlock(reinterpret_cast<Address>(mem), alloced);
+#endif
   Counters::memory_allocated.Increment(alloced);
   return mem;
 }
 
 
 void MemoryAllocator::FreeRawMemory(void* mem, size_t length) {
+#ifdef DEBUG
+  ZapBlock(reinterpret_cast<Address>(mem), length);
+#endif
   if (CodeRange::contains(static_cast<Address>(mem))) {
     CodeRange::FreeRawMemory(mem, length);
   } else {
     OS::Free(mem, length);
   }
   Counters::memory_allocated.Decrement(static_cast<int>(length));
   size_ -= static_cast<int>(length);
   ASSERT(size_ >= 0);
 }
 
@@ skipping 63 matching lines @@
                                    PagedSpace* owner, int* num_pages) {
   ASSERT(start != NULL);
   *num_pages = PagesInChunk(start, size);
   ASSERT(*num_pages > 0);
   ASSERT(initial_chunk_ != NULL);
   ASSERT(InInitialChunk(start));
   ASSERT(InInitialChunk(start + size - 1));
   if (!initial_chunk_->Commit(start, size, owner->executable() == EXECUTABLE)) {
     return Page::FromAddress(NULL);
   }
+#ifdef DEBUG
+  ZapBlock(start, size);
+#endif
   Counters::memory_allocated.Increment(static_cast<int>(size));
 
   // So long as we correctly overestimated the number of chunks we should not
   // run out of chunk ids.
   CHECK(!OutOfChunkIds());
   int chunk_id = Pop();
   chunks_[chunk_id].init(start, size, owner);
   return InitializePagesInChunk(chunk_id, *num_pages, owner);
 }
 
 
 bool MemoryAllocator::CommitBlock(Address start,
                                   size_t size,
                                   Executability executable) {
   ASSERT(start != NULL);
   ASSERT(size > 0);
   ASSERT(initial_chunk_ != NULL);
   ASSERT(InInitialChunk(start));
   ASSERT(InInitialChunk(start + size - 1));
 
   if (!initial_chunk_->Commit(start, size, executable)) return false;
+#ifdef DEBUG
+  ZapBlock(start, size);
+#endif
   Counters::memory_allocated.Increment(static_cast<int>(size));
   return true;
 }
 
+
 bool MemoryAllocator::UncommitBlock(Address start, size_t size) {
   ASSERT(start != NULL);
   ASSERT(size > 0);
   ASSERT(initial_chunk_ != NULL);
   ASSERT(InInitialChunk(start));
   ASSERT(InInitialChunk(start + size - 1));
 
   if (!initial_chunk_->Uncommit(start, size)) return false;
   Counters::memory_allocated.Decrement(static_cast<int>(size));
   return true;
 }
 
+
+void MemoryAllocator::ZapBlock(Address start, size_t size) {
+  for (size_t s = 0; s + kPointerSize <= size; s += kPointerSize) {
+    Memory::Address_at(start + s) = kZapValue;
+  }
+}
+
+
 Page* MemoryAllocator::InitializePagesInChunk(int chunk_id, int pages_in_chunk,
                                               PagedSpace* owner) {
   ASSERT(IsValidChunk(chunk_id));
   ASSERT(pages_in_chunk > 0);
 
   Address chunk_start = chunks_[chunk_id].address();
 
   Address low = RoundUp(chunk_start, Page::kPageSize);
 
 #ifdef DEBUG
@@ skipping 1096 matching lines @@
       cur = i;
     }
   }
   free_[cur].next_size_ = kEnd;
   needs_rebuild_ = false;
 }
 
 
 int OldSpaceFreeList::Free(Address start, int size_in_bytes) {
 #ifdef DEBUG
-  for (int i = 0; i < size_in_bytes; i += kPointerSize) {
-    Memory::Address_at(start + i) = kZapValue;
-  }
+  MemoryAllocator::ZapBlock(start, size_in_bytes);
 #endif
   FreeListNode* node = FreeListNode::FromAddress(start);
   node->set_size(size_in_bytes);
 
   // We don't use the freelists in compacting mode.  This makes it more like a
   // GC that only has mark-sweep-compact and doesn't have a mark-sweep
   // collector.
   if (FLAG_always_compact) {
     return size_in_bytes;
   }
@@ skipping 111 matching lines @@
 
 
 void FixedSizeFreeList::Reset() {
   available_ = 0;
   head_ = NULL;
 }
 
 
 void FixedSizeFreeList::Free(Address start) {
 #ifdef DEBUG
-  for (int i = 0; i < object_size_; i += kPointerSize) {
-    Memory::Address_at(start + i) = kZapValue;
-  }
+  MemoryAllocator::ZapBlock(start, object_size_);
 #endif
   // We only use the freelists with mark-sweep.
   ASSERT(!MarkCompactCollector::IsCompacting());
   FreeListNode* node = FreeListNode::FromAddress(start);
   node->set_size(object_size_);
   node->set_next(head_);
   head_ = node->address();
   available_ += object_size_;
 }
 
@@ skipping 1103 matching lines @@
                      reinterpret_cast<Object**>(object->address()
                                                 + Page::kObjectAreaSize),
                      allocation_top);
       PrintF("\n");
     }
   }
 }
 #endif  // DEBUG
 
 } }  // namespace v8::internal