cpp_padding_optimizer.h

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// Protocol Buffers - Google's data interchange format
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// Author: seongkim@google.com (Seong Beom Kim)
//  Based on original Protocol Buffers design by
//  Sanjay Ghemawat, Jeff Dean, and others.
 
#ifndef GOOGLE_PROTOBUF_COMPILER_CPP_PADDING_OPTIMIZER_H__
#define GOOGLE_PROTOBUF_COMPILER_CPP_PADDING_OPTIMIZER_H__
 
#include <google/protobuf/compiler/cpp/cpp_message_layout_helper.h>
 
namespace google {
namespace protobuf {
namespace compiler {
namespace cpp {
 
// Rearranges the fields of a message to minimize padding.
// Fields are grouped by the type and the size.
// For example, grouping four boolean fields and one int32
// field results in zero padding overhead. See OptimizeLayout's
// comment for details.
class PaddingOptimizer : public MessageLayoutHelper {
 public:
  PaddingOptimizer() {}
  ~PaddingOptimizer() override {}
 
  void OptimizeLayout(std::vector<const FieldDescriptor*>* fields,
                      const Options& options) override;
};
 
}  // namespace cpp
}  // namespace compiler
}  // namespace protobuf
}  // namespace google
 
#endif  // GOOGLE_PROTOBUF_COMPILER_CPP_PADDING_OPTIMIZER_H__