Replaying Time-Travel Traces on Non-Identical Processors

The patent introduces an intermediary layer (the debugging system with its trace recording and replay mechanisms) that mediates between the processor's undefined behaviors and the debugging requirements. This intermediary captures processor states, memory contents, and instruction sequences during recording, then replays them on potentially different hardware, isolating the variability of undefined behaviors from the debugging process itself

The system changes the parameters of the replay environment, allowing traces recorded on one processor model to be replayed on different processor models. By capturing sufficient state information during recording and using it to drive replay, the system transforms the rigid requirement of identical hardware into a flexible system that can adapt to different processor configurations while maintaining debugging reliability

The patent segments the trace recording process into distinct components: instruction sequences, memory states, register states, and processor flags. This segmentation allows the system to capture only the essential state information needed for accurate replay, rather than forcing single-threaded execution. Multiple threads can execute concurrently while their states are individually captured and replayed in the correct sequence

Instead of capturing every single instruction execution detail (excessive action), the system captures partial but sufficient state information (processor states, memory contents, instruction sequences) that enables accurate replay. This partial action approach maintains trace completeness while allowing concurrent multi-threaded execution during recording, improving productivity without sacrificing measurement precision