Constraints and Object Queries - 2022.1 English

Vivado Design Suite User Guide: Using Constraints (UG903)

Document ID
UG903
Release Date
2022-06-01
Version
2022.1 English

Design constraints that contain object queries based on some physical information must not rely on physical constraints entered by Vivado P&R commands, and only rely on physical constraints that the user enters, else such constraints will appear invalid when reloading a post-implementation DCP. This requirement comes from the DCP load sequence where the netlist is read first, then the constraints and physical database last. Instead of using physical information, you should modify the query to depend on other design objects properties (NAME, REF_NAME, ...).

Example of non-recommended constraint relying on placement information (property LOC):

set_false_path -from [get_cells -quiet -hier -filter {REF_NAME=~FD* && LOC=~BLI_*}]