List of Nodes for the -through Option - List of Nodes for the -through Option - 2026.1 English - UG903

Vivado Design Suite User Guide: Using Constraints (UG903)
Document ID
UG903
Release Date
2026-07-01
Version
2026.1 English
  • The list of nodes for the -through option must be a list of valid pins, ports, or nets.
  • Multiple elements can be provided.

By default, the timing engine includes clock skew in the slack computation. The -datapath_only option removes clock skew from the slack computation. This option is supported only by the set_max_delay command and requires the -from option.

Common behavior for path delay calculation, whether -datapath_only is used or not:

  • Input delay is included in the path delay when the path starts on an input port and a set_input_delay is applied to that port.
  • Output delay is included in the path delay when the path ends on an output port and a set_output_delay is applied to that port.
  • The setup time of the data pin is included in the path delay when the path ends on the data pin of a sequential element.

The following table summarizes the behavior of set_max_delay with and without the -datapath_only option.

Table 1. Differences Between Max Delay Constraint With and Without -datapath_only
set_max_delay set_max_delay -datapath_only
Path delay calculation Skew included when the constraint starts on a clock pin or ends on a data pin of a sequential element Skew never included
Hold Requirement Untouched Path treated as false for hold analysis
-from Option Optional Mandatory