Root-cause analysis for memory-locked errors

Abstract

Half of the time in the design cycle today is spent on verifying and debugging the correctness of a design. Although some debugging tasks have been automated, determining the root-cause of errors that have been locked in memory for a number of clock cycles before they propagate to an observation point remains a time consuming effort. This is because the error traces exposing such behavior can be excessively long, a fact that requires modeling the circuit for many time-frames. This paper introduces a performance-driven debugging methodology for pinpointing the root-cause of memory-locked errors. The technique models only a sliding time window and a final time window explicitly at any one time, while interstitial time-frames are linked with a lightweight memory model. This technique is later extended to a complete methodology that diagnoses errors that may be missed. Experiments on industrial designs with memory-locked errors demonstrate a 72% reduction in peak memory usage with a comparable runtime to existing methodologies.