Merge pull request #41 from litghost/rework_mode_support

Do allow fasm_lut in mode or in pb_type with 1 mode.

Author: litghost

doc/src/utils/fasm.rst

@@ -148,10 +148,12 @@ example:
      </meta>
    </metadata>
 
-FASM LUT metadata must be attached to the ``<pb_type>`` at or directly above
-the ``<pb_type>`` with ``blif_model=".names"``.  The FASM LUT metadata tags
-will not be recognized attached inside of ``<mode>`` tags or inside
-``<pb_type>``'s higher than 1 level above the leaf type.
+FASM LUT metadata must be attached to the ``<pb_type>`` at or within the
+``<mode>`` tag directly above the ``<pb_type>`` with ``blif_model=".names"``.
+Do note that there is an implicit ``<mode>`` tag within intermediate
+``<pb_type>`` when no explicit ``<mode>`` tag is present. The FASM LUT
+metadata tags will not be recognized attached inside of ``<pb_type>``'s higher
+above the leaf type.
 
 When specifying a FASM features with more than one bit, explicitly specify the
 bit range being set.  This is required because "genfasm" does not have access

utils/fasm/src/fasm.cpp

@@ -382,8 +382,12 @@ static const t_metadata_dict *get_fasm_type(const t_pb_graph_node* pb_graph_node
   if(pb_graph_node->pb_type->parent_mode != nullptr) {
     VTR_ASSERT(pb_graph_node->pb_type->parent_mode->parent_pb_type != nullptr);
     const t_pb_type *pb_type = pb_graph_node->pb_type->parent_mode->parent_pb_type;
-    if(pb_type->meta.has("fasm_type")) {
-      meta = &pb_type->meta;
+    if(pb_graph_node->pb_type->parent_mode->meta.has("fasm_type")) {
+      meta = &pb_graph_node->pb_type->parent_mode->meta;
+    } else if(pb_type->num_modes <= 1) {
+      if(pb_type->meta.has("fasm_type")) {
+        meta = &pb_type->meta;
+      }
     }
   }