6938 - How to avoid the resource get optimized  during Synthesis?

6938 - How to avoid the resource get optimized  during Synthesis?

This is due to the optimization in the design during MAP.
To avoid optimization during MAP, use syn_hier in the block level (submodules) and syn_keep + NOCLIP to the instance component at the top level file.
Example:
1. Insert the attribute /* synthesis syn_hier="fixed" */ to the block level file (submodule).