Resolve crash in MatMul optimization (#5551)

* check pointer before referencing

* add test case

* switch to ASSERT_EQ

onnxruntime/core/optimizer/matmul_add_fusion.cc

@@ -88,6 +88,9 @@ Status MatMulAddFusion::ApplyImpl(Graph& graph, bool& modified, int graph_level,
 
     // valid bias_shapes are (N) or (1, N) or (M, 1) or (M, N) as
     // GEMM only supports unidirectional broadcast on the bias input C
+    if (!gemm_input_defs.back()->Shape()) {
+        continue;
+    }
     const auto& bias_shape = *gemm_input_defs.back()->Shape();
     const auto& M = matmul_output.Shape()->dim()[0];
     const auto& N = matmul_output.Shape()->dim()[1];

onnxruntime/test/optimizer/graph_transform_test.cc

@@ -681,6 +681,23 @@ TEST_F(GraphTransformationTests, MatMulAddFusion_NotBroadcastable) {
   ASSERT_TRUE(op_to_count["Gemm"] == 0);
 }
 
+TEST_F(GraphTransformationTests, MatMulAddFusion_MissingShape) {
+  auto model_uri = MODEL_FOLDER "matmul_add_fusion/matmul_add_missing_shape.onnx";
+
+  std::shared_ptr<Model> p_model;
+  ASSERT_STATUS_OK(Model::Load(model_uri, p_model, nullptr, *logger_));
+  Graph& graph = p_model->MainGraph();
+
+  onnxruntime::GraphTransformerManager graph_transformation_mgr{5};
+  graph_transformation_mgr.Register(onnxruntime::make_unique<MatMulAddFusion>(), TransformerLevel::Level1);
+  ASSERT_STATUS_OK(graph_transformation_mgr.ApplyTransformers(graph, TransformerLevel::Level1, *logger_));
+
+  std::map<std::string, int> op_to_count = CountOpsInGraph(graph);
+  ASSERT_EQ(op_to_count["MatMul"], 1);
+  ASSERT_EQ(op_to_count["Add"], 1);
+  ASSERT_EQ(op_to_count["Gemm"], 0);
+}
+
 #ifndef DISABLE_CONTRIB_OPS
 TEST_F(GraphTransformationTests, Gemm_Relu_three_input) {
   auto model_uri = MODEL_FOLDER "matmul_add_fusion/3Input/gemm_relu.onnx";

onnxruntime/test/testdata/transform/matmul_add_fusion/matmul_add_missing_shape.onnx

@@ -0,0 +1,19 @@
+:j
+
+
A
+
B
S"MatMul
+
+
S
+
C
D"AddgraphZ
+
A
+

+
+Z
+
B
+

+
+Z	
+
C
+
b	
+
D
+
B