Exceptions Priority Example - Exceptions Priority Example - 2026.1 English - UG903

Vivado Design Suite User Guide: Using Constraints (UG903)

Document ID
UG903
Release Date
2026-07-01
Version
2026.1 English
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 for paths from clk1 to clk2.

The number of -through options you use in an exception does not change precedence. The timing engine applies 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 uses cell objects only, and the second uses a clock object. Even though inst0 is clocked by clk1, your first constraint overrides the second for paths from inst0 to inst1.