How to set group number for a group of block ?

[migen]

My big EA has many blocks. I want each of groups works independently by setting group number. However, there are a lot of blocks.
My question : is there anyway to set a group number for a group of block without entering number into each block (time-consuming task) ?

[roar]

@migen I'd say using a variable in the group number is the best option, you will have to touch every block, though.

Also make sure that your system is not unnecessarily big, usually you can reuse the same blocks with a loop...