You can use the group_path command with the -weight option to give higher priority to the path endpoints defined in a clock group. For example, to assign a higher priority to group of logic clocked by a specific clock, use the following command:
group_path -name [get_clocks clock] -weight 2In this example, the implementation tools give higher priority to the paths that belong to clock group clock with a weight of 2 over other paths in the design.