TMC-20002: Timing Paths With Impossible Removal Requirement
Timing paths with a very large negative removal requirement (greater than
-0.3 nS) complicate timing closure and may cause excessively long run times.
Such paths are mostly invalid and require appropriate timing constraints, such as:
- set_false_path for invalid timing path or
- set_multicycle_path to adjust clock edges of a multi-cycle recovery path.
Note: The removal_requirement_threshold_level rule parameter filters out hold
paths with more stringent timing requirements (that is, a smaller slack value).
Specify a negative value for this parameter that is a specific fraction (for
example, 50%) of the design's clock period to multiple clock cycles.
Parameter
| Name | Default Value | Description |
|---|---|---|
| removal_requirement_threshold_level | -0.3 nS |
A violation is reported for timing paths that have removal time slack lower than the value specified in this parameter. |
Recommendation
Ensure that it is a valid timing path. Otherwise, consider an appropriate exception (set_false_path or set_multicycle_path) or restructure the path.
Severity
High
Stage
Plan, Place, Finalize
Device Family
- Intel® Stratix® 10
- Intel® Agilex™
- Intel® Cyclone® 10 GX
- Intel® Arria® 10