Five-Minute Tutorial: Default Naming Conventions in Encounter Digital Implementation (EDI)

27 Feb 2012 • 2 minute read

This is a topic that frequently comes up on both internal and external forums. And the answer is right in the Encounter Digital Implementation System (EDI) User Guide, but unless you already know that, you may not think to look for it there.

At some point, all of us have looked at a timing report, and reviewed the list of cells that EDI added during timing optimization. Then we wondered, "Hmmm. What does that prefix mean?" I'm sure you've seen the prefixes of the form FE_PHC, FE_RC, FE_OFC, etc. They do have specific meanings, and when debugging a timing path, it can be very helpful to know where these cells came from.

The following list is located in the EDI User Guide. It's at the end of the Optimizing Timing chapter, in a section called Default Naming Conventions.

Prefix	Description	Command
FE_MDBC	Instance added by multi-driver net buffering	optDesign
FE_MDBN	Net added by multi-driver net buffering	optDesign
FE_OCP_DRV_C	Instance added by DRV fixing	optDesign
FE_OCP_DRV_N	Net added by DRV fixing	optDesign
FE_OCP_RBC	Instance added by rebuffering	optDesign
FE_OCP_RBN	Net added by rebuffering	optDesign
FE_OCPC	Instance added by critical path optimization	optDesign
FE_OCPN	Net added by critical path optimization	optDesign
FE_OFC	Buffer instance added by rule-based buffer insertion	insertRepeater/optDesign
FE_OFN	Buffer net added by rule-based buffer insertion	insertRepeater/optDesign
FE_PHC	Instance added by hold time repair	optDesign
FE_PHN	Net added by hold time repair	optDesign
FE_PSBC	Instance added by buffer insertion in optDesign -postRoute	optDesign
FE_PSBN	Net added by buffer insertion in optDesign -postRoute	optDesign
FE_PSC	Instance added by postroute setuprepair	optDesign
FE_PSN	Net added by postroute setup repair	optDesign
FE_RC	Instance created by netlist restructuring	optDesign
FE_RN	Net created by netlist restructuring	optDesign
FE_USC	Instance added during useful skew optimization	optDesign

Hopefully this information will help you debug a timing path gone wrong, and prompt you to check out the EDI User Guide!

Here are two previous blogs related to debugging timing in EDI:

Demo: Calling Global Timing Debug for a Single Path

An Interview with Global Timing Debug Architect Thad McCracken

- Kari Summers