Add an operator node in unittest to make the fusing result unique. (#24617)

paddle/fluid/framework/ir/fusion_group/fusion_group_pass.cc

@@ -82,7 +82,7 @@ int FusionGroupPass::DetectFusionGroup(Graph* graph, int type) const {
 bool FusionGroupPass::GenerateCode(fusion_group::SubGraph* subgraph) const {
   fusion_group::CodeGenerator code_generator;
   std::string code_str = code_generator.Generate(subgraph);
-  VLOG(3) << code_str;
+  VLOG(4) << code_str;
 
   // TODO(liuyiqun): supported different places
   platform::CUDAPlace place = platform::CUDAPlace(0);

python/paddle/fluid/tests/unittests/ir/test_ir_fusion_group_pass.py

@@ -122,7 +122,7 @@ class FusionGroupPassTestFP64(FusionGroupPassTest):
         self.fused_op_type = "fusion_group"
 
 
-class FusionGroupPassTestFP16(FusionGroupPassTest):
+class FusionGroupPassTestCastAndFP16(FusionGroupPassTest):
     def build_program(self, dtype):
         with fluid.program_guard(self.main_program, self.startup_program):
             self.feed_vars = self._prepare_feed_vars([32, 128], dtype, 2)
@@ -132,7 +132,7 @@ class FusionGroupPassTestFP16(FusionGroupPassTest):
 
             # subgraph with 2 op nodes
             tmp_0 = self.feed_vars[0] * self.feed_vars[1]
-            tmp_1 = layers.cast(tmp_0, dtype="float16")
+            tmp_1 = layers.softmax(layers.cast(tmp_0, dtype="float16"))
             tmp_2 = layers.mul(tmp_0, self.feed_vars[2])
             # subgraph with 4 op nodes
             tmp_3 = layers.cast(tmp_2, dtype="float16")
@@ -141,7 +141,7 @@ class FusionGroupPassTestFP16(FusionGroupPassTest):
 
         self.append_gradients(tmp_5)
 
-        self.num_fused_ops = 3
+        self.num_fused_ops = 4
         self.fetch_list = [tmp_5, self.grad(tmp_0)]