fix InferShapeContext Has interface (#4994)

paddle/framework/operator.h

@@ -327,6 +327,9 @@ class CompileTimeInferShapeContext : public InferShapeContext {
   bool HasInput(const std::string& name) const override {
     const std::vector<std::string>& input_names = op_.Input(name);
     auto length = input_names.size();
+    if (length == 0) {
+      return false;
+    }
     PADDLE_ENFORCE_EQ(length, 1UL,
                       "Input(%s) should have only one value, "
                       "but it have %d now",
@@ -337,6 +340,9 @@ class CompileTimeInferShapeContext : public InferShapeContext {
   bool HasOutput(const std::string& name) const override {
     const std::vector<std::string>& output_names = op_.Output(name);
     auto length = output_names.size();
+    if (length == 0) {
+      return false;
+    }
     PADDLE_ENFORCE_EQ(length, 1UL,
                       "Output(%s) should have only one value, "
                       "but it have %d now",
@@ -346,7 +352,9 @@ class CompileTimeInferShapeContext : public InferShapeContext {
 
   bool HasInputs(const std::string& name) const override {
     const std::vector<std::string>& input_names = op_.Input(name);
-    PADDLE_ENFORCE(!input_names.empty(), "Inputs(%s) length is 0", name);
+    if (input_names.empty()) {
+      return false;
+    }
     for (auto& input : input_names) {
       if (!block_.HasVar(input)) return false;
     }
@@ -355,7 +363,9 @@ class CompileTimeInferShapeContext : public InferShapeContext {
 
   bool HasOutputs(const std::string& name) const override {
     const std::vector<std::string>& output_names = op_.Output(name);
-    PADDLE_ENFORCE(!output_names.empty(), "Inputs(%s) length is 0", name);
+    if (output_names.empty()) {
+      return false;
+    }
     for (auto& output : output_names) {
       if (!block_.HasVar(output)) return false;
     }
@@ -421,13 +431,27 @@ class RuntimeInferShapeContext : public InferShapeContext {
       : op_(op), scope_(scope) {}
 
   bool HasInput(const std::string& name) const override {
-    auto ipt = op_.Input(name);
+    auto& ins = Inputs(name);
+    size_t length = ins.size();
+    if (length == 0) {
+      return false;
+    }
+    PADDLE_ENFORCE_EQ(length, 1UL, "Input %s should have more than one inputs",
+                      name);
+    auto ipt = ins[0];
     auto* var = ipt == kEmptyVarName ? nullptr : scope_.FindVar(ipt);
     return var != nullptr;
   }
 
   bool HasOutput(const std::string& name) const override {
-    auto ipt = op_.Output(name);
+    auto& outs = Outputs(name);
+    size_t length = outs.size();
+    if (length == 0) {
+      return false;
+    }
+    PADDLE_ENFORCE_EQ(length, 1UL, "Output %s should have more than one inputs",
+                      name);
+    auto ipt = outs[0];
     auto* var = ipt == kEmptyVarName ? nullptr : scope_.FindVar(ipt);
     return var != nullptr;
   }