fix roi align x86 kernel to support batchsize==1 and lod empty

lite/kernels/x86/roi_align_compute.cc

@@ -119,6 +119,7 @@ void RoiAlignCompute::Run() {
   auto rois_dims = rois->dims();
   int rois_num = rois_dims[0];
   auto out_dims = out->dims();
+
   if (rois_num == 0) {
     return;
   }
@@ -138,14 +139,18 @@ void RoiAlignCompute::Run() {
   roi_batch_id_list.Resize({rois_num});
   int* roi_batch_id_data = roi_batch_id_list.mutable_data<int>();
 
-  auto rois_lod = rois->lod().back();
-  int rois_batch_size = rois_lod.size() - 1;
-  // CHECK_OR_FALSE(rois_batch_size == batch_size);
-  // int rois_num_with_lod = rois_lod[rois_batch_size];
-  // CHECK_OR_FALSE(rois_num_with_lod == rois_num);
-  for (int n = 0; n < rois_batch_size; ++n) {
-    for (size_t i = rois_lod[n]; i < rois_lod[n + 1]; ++i) {
-      roi_batch_id_data[i] = n;
+  if (rois->lod().empty() && in_dims[0] /* batch_size */ == 1) {
+    std::fill_n(roi_batch_id_data, rois_num, 0);
+  } else {
+    auto rois_lod = rois->lod().back();
+    int rois_batch_size = rois_lod.size() - 1;
+    // CHECK_OR_FALSE(rois_batch_size == batch_size);
+    // int rois_num_with_lod = rois_lod[rois_batch_size];
+    // CHECK_OR_FALSE(rois_num_with_lod == rois_num);
+    for (int n = 0; n < rois_batch_size; ++n) {
+      for (size_t i = rois_lod[n]; i < rois_lod[n + 1]; ++i) {
+        roi_batch_id_data[i] = n;
+      }
     }
   }