check_library validates the libraries i.e., it performs consistency checks between logical and physical libraries, across logical libraries, and within physical libraries.
This command checks library qualities in three main areas:
- Physical library quality
- Logic versus physical library consistency
- Logic versus logic library consistency
PNR tool wont optimize the paths which are not constrained. So we have to check any unconstrained paths are exist in the design. check_timing command reports unconstrained paths.
If there are any unconstrained paths in the design, run the report_timing_requirements command to verify that the unconstrained paths are false paths.
It reports to check the following parameters.
- Worst Negative Slack (WNS)
- Total Negative Slack (TNS)
- Design Rule Constraint Violations
report_timing displays timing information about a design.
The report_timing command provides a report of timing information for the current design. By default, the report_timing command reports the single worst setup path in each clock group.
report_qor displays QoR information and statistics for the current design. This command reports timing-path group and cell count details, along with current design statistics such as combinational, noncombinational, and total area.
The command also reports static power, design rule violations, and compile-time details.
check_design checks the current design for consistency.
The check_design command checks the internal representation of the current design for consistency, and issues error and warning messages as appropriate.
- Error messages indicate design problems of such severity that the compile command does not accept the design
- Warning messages are informational and do not necessarily indicate design problems. However, these messages should be investigated.
Potential problems detected by this command include
- Unloaded input ports or undriven output ports
- Nets without loads or drivers or with multiple drivers
- Cells or designs without inputs or outputs
- Mismatched pin counts between an instance and its reference
- Tristate buses with non-tristate drivers
- wire loops across hierarchies, and so forth.