fix affine_channel no_need buffer bug, test=release/1.5 (#18849)

paddle/fluid/operators/affine_channel_op.cc

@@ -295,10 +295,10 @@ class AffineChannelNoNeedBufferVarsInference
   using framework::NoNeedBufferVarsInference::NoNeedBufferVarsInference;
 
  private:
-  inline bool HasInput(const std::string& name) const {
-    auto& inputs = Inputs();
-    auto iter = inputs.find(name);
-    if (iter == inputs.end() || iter->second.empty()) {
+  inline bool HasOutput(const std::string& name) const {
+    auto& outputs = Outputs();
+    auto iter = outputs.find(name);
+    if (iter == outputs.end() || iter->second.empty()) {
       return false;
     } else {
       return iter->second[0] != framework::kEmptyVarName;
@@ -306,9 +306,9 @@ class AffineChannelNoNeedBufferVarsInference
   }
 
  public:
-  std::unordered_set<std::string> operator()() const {
-    if (!HasInput(framework::GradVarName("Scale")) &&
-        !HasInput(framework::GradVarName("Bias"))) {
+  std::unordered_set<std::string> operator()() const override {
+    if (!HasOutput(framework::GradVarName("Scale")) &&
+        !HasOutput(framework::GradVarName("Bias"))) {
       return {"X"};
     } else {
       return {};

python/paddle/fluid/tests/unittests/CMakeLists.txt

@@ -126,6 +126,7 @@ list(REMOVE_ITEM TEST_OPS test_basic_lstm_unit_op)
 # Some ops need to check results when gc is enabled
 # Currently, only ops that register NoNeedBufferVarsInference need to do this test   
 set(TEST_OPS_WITH_GC
+  test_affine_channel_op
   test_concat_op
   test_elementwise_add_op
   test_elementwise_sub_op