Exceptions Priority Example - 2025.1 English - UG903

set_max_delay 12 -from [get_clocks clk1] -to [get_clocks clk2]
set_max_delay 15 -from [get_clocks clk1]

In this example, the first constraint overrides the second constraint for the paths from clk1 to clk2.

The number of -through options used in an exception does not affect the precedence. The timing engine uses the tightest constraint.

set_max_delay 12 -from [get_cells inst0] -to [get_cells inst1]
set_max_delay 15 -from [get_clocks clk1] -through [get_pins hier0/p0] -to [get_cells inst1]

In this example, the first constraint only uses cell objects and the second constraint uses a clock object. Although inst0 is clocked by clk1, the first constraint overrides the second constraint for the paths from cell inst0 to cell inst1.