Hardware-Based Data Value and Address Trace Filtering Techniques
Capturing program and data traces during program execution unobtrusively in real-time is crucial in debugging and testing of cyber-physical systems. However, tracing a complete program unobtrusively is often cost-prohibitive, requiring large on-chip trace buffers and wide trace ports. Whereas program execution traces can be efficiently compressed in hardware, compression of data address and data value traces is much more challenging due to limited redundancy. In this paper, the authors describe two hardware-based filtering techniques for data traces: cache first-access tracking for load data values and data address filtering using partial register-file replay.