[MSLITE] Fix bug of fp16subgraph preprocess.

mindspore/ccsrc/backend/kernel_compiler/cpu/nnacl/infer/where_infer.c

@@ -31,6 +31,8 @@ int WhereInferShape(const TensorC *const *inputs, size_t inputs_size, TensorC **
 
   // Need to dynamically allocate at runtime.
   if (inputs_size == 1) {
+    output->data_type_ = kNumberTypeInt32;
+    output->format_ = input->format_;
     return NNACL_INFER_INVALID;
   }
 

mindspore/lite/src/runtime/kernel/arm/fp32/where_fp32.cc

@@ -89,7 +89,6 @@ int WhereCPUKernel::RunWithSingleInput() {
       }
     }
   }
-  out_tensors_.at(0)->set_data_type(kNumberTypeInt32);
   std::vector<int> output_shape = {true_num, where_param_->rank_};
   out_tensors_.at(0)->set_shape(output_shape);
   out_tensors_.at(0)->FreeData();

mindspore/lite/src/sub_graph_kernel.cc

@@ -226,12 +226,13 @@ int CpuFp16SubGraph::Float32TensorToFloat16Tensor(lite::Tensor *tensor) {
   MS_ASSERT(tensor != nullptr);
   auto float32_data = tensor->data_c();
   auto own_data = tensor->own_data();
+  tensor->set_data_type(TypeId::kNumberTypeFloat16);
   if (float32_data == nullptr) {
-    MS_LOG(ERROR) << "tensor data is null.";
-    return lite::RET_NULL_PTR;
+    // the input data may be nullptr of merge.
+    MS_LOG(INFO) << "tensor data is null.";
+    return lite::RET_OK;
   }
   tensor->set_data(nullptr);
-  tensor->set_data_type(TypeId::kNumberTypeFloat16);
   auto ret = tensor->MallocData();
   if (RET_OK != ret) {
     MS_LOG(ERROR) << "malloc data failed";

mindspore/lite/test/models_onnx_fp16.cfg

@@ -79,3 +79,4 @@ Q_face_recognition.onnx 2
 ml_video_edit_enhance_update_tmp.onnx 0.5
 Q888_face_recognition.onnx 3.5
 Q888_iris_detect.onnx 0.5
+ssd_mobilenet_v1_10.onnx;1,383,640,3 0.5