Dump stats of memory pages which are hooked, but absent from /proc/<pid>/maps.

third_party/tcmalloc/chromium/src/deep-heap-profile.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // ---
 // Author: Sainbayar Sukhbaatar
 //         Dai Mikurube
 //
 // This file contains a class DeepHeapProfile and its public function
 // DeepHeapProfile::FillOrderedProfile() which works as an alternative of
@@ skipping 212 matching lines @@
     // 'committed_bytes' in the region from |first_adress| to |last_address|
     // inclusive.
     uint64 Record(
         const MemoryResidenceInfoGetterInterface* memory_residence_info_getter,
         uint64 first_address,
         uint64 last_address);
 
     // Writes stats of the region into |buffer| with |name|.
     void Unparse(const char* name, TextBuffer* buffer);
 
+    size_t virtual_bytes() const { return virtual_bytes_; }
     size_t committed_bytes() const { return committed_bytes_; }
     void AddToVirtualBytes(size_t additional_virtual_bytes) {
       virtual_bytes_ += additional_virtual_bytes;
     }
     void AddToCommittedBytes(size_t additional_committed_bytes) {
       committed_bytes_ += additional_committed_bytes;
     }
     void AddAnotherRegionStat(const RegionStats& other) {
       virtual_bytes_ += other.virtual_bytes_;
       committed_bytes_ += other.committed_bytes_;
@@ skipping 59 matching lines @@
 
   DeepBucketTable deep_table_;
 #endif  // DEEP_HEAP_PROFILE
 
   HeapProfileTable* heap_profile_;
 
   DISALLOW_COPY_AND_ASSIGN(DeepHeapProfile);
 };
 
 #endif  // BASE_DEEP_HEAP_PROFILE_H_