1    :  // Copyright 2012 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  //
  15    :  #ifndef SYZYGY_REORDER_DEAD_CODE_FINDER_H_
  16    :  #define SYZYGY_REORDER_DEAD_CODE_FINDER_H_
  17    :  
  18    :  #include <set>
  19    :  
  20    :  #include "syzygy/reorder/reorderer.h"
  21    :  
  22  m :  namespace reorder {
  23    :  
  24    :  // Identifies code symbols which are not referenced by a given call trace.
  25  m :  class DeadCodeFinder : public Reorderer::OrderGenerator {
  26  m :   public:
  27  m :    typedef BlockGraph::Block Block;
  28    :  
  29  m :    DeadCodeFinder();
  30  m :    virtual ~DeadCodeFinder();
  31    :  
  32    :    // Returns true if the block is of interest and unvisited.
  33  m :    bool IsDead(const Block* block) const;
  34    :  
  35    :    // OrderGenerator implementation.
  36    :    // @{
  37  m :    virtual bool OnCodeBlockEntry(const Block* block,
  38  m :                                  RelativeAddress address,
  39  m :                                  uint32 process_id,
  40  m :                                  uint32 thread_id,
  41  m :                                  const UniqueTime& time) override;
  42  m :    virtual bool CalculateReordering(const PEFile& pe_file,
  43  m :                                     const ImageLayout& image,
  44  m :                                     bool reorder_code,
  45  m :                                     bool reorder_data,
  46  m :                                     Order* order) override;
  47    :    // @}
  48    :  
  49  m :   protected:
  50    :    // The set of blocks observed while reading the call trace.
  51  m :    std::set<const Block*> visited_blocks_;
  52    :  
  53  m :   private:
  54  m :    DISALLOW_COPY_AND_ASSIGN(DeadCodeFinder);
  55  m :  };
  56    :  
  57  m :  }  // namespace reorder
  58    :  
  59    :  #endif  // SYZYGY_REORDER_DEAD_CODE_FINDER_H_