infer get program (#15511)

Author: Superjomn

paddle/fluid/inference/api/analysis_predictor.cc

@@ -726,6 +726,10 @@ bool AnalysisPredictor::need_collect_var_shapes_for_memory_optim() {
   return need;
 }
 
+std::string AnalysisPredictor::GetSeriazlizedProgram() const {
+  return inference_program_->Proto()->SerializeAsString();
+}
+
 template <>
 std::unique_ptr<PaddlePredictor> CreatePaddlePredictor<contrib::AnalysisConfig>(
     const contrib::AnalysisConfig &config) {

paddle/fluid/inference/api/analysis_predictor.h

@@ -75,6 +75,8 @@ class AnalysisPredictor : public PaddlePredictor {
 
   void SetMkldnnThreadID(int tid);
 
+  std::string GetSeriazlizedProgram() const override;
+
  protected:
   // For memory optimization.
   bool need_collect_var_shapes_for_memory_optim();

paddle/fluid/inference/api/analysis_predictor_tester.cc

@@ -215,6 +215,8 @@ TEST(AnalysisPredictor, memory_optim) {
   {
     // The first predictor help to cache the memory optimize strategy.
     auto predictor = CreatePaddlePredictor<AnalysisConfig>(config);
+    LOG(INFO) << "serialized program: " << predictor->GetSeriazlizedProgram();
+    ASSERT_FALSE(predictor->GetSeriazlizedProgram().empty());
 
     // Run several times to check the parameters are not reused by mistake.
     for (int i = 0; i < 5; i++) {

paddle/fluid/inference/api/paddle_api.h

@@ -215,6 +215,14 @@ class PaddlePredictor {
    */
   virtual ~PaddlePredictor() = default;
 
+  /** \brief Get the serialized model program that executes in inference phase.
+   * Its data type is ProgramDesc, which is a protobuf message.
+   */
+  virtual std::string GetSeriazlizedProgram() const {
+    assert(false);  // Force raise error.
+    return "NotImplemented";
+  };
+
   /** The common configs for all the predictors.
    */
   struct Config {