Microsoft Corporation
COPROCESSOR-BASED LOGGING FOR TIME TRAVEL DEBUGGING

Abstract:

A tracing coprocessor that records execution trace data based on a cache coherency protocol (CCP) message. The tracing coprocessor comprises logic that causes the tracing coprocessor to listen on a bus that is communicatively coupled to a primary processor that executes executable code instructions. The logic also causes the tracing coprocessor to, based on listening on the bus, identify at least one CCP message relating to activity at a processor cache. The logic also causes the tracing coprocessor to identify, from the at least one CCP message, a memory cell consumption by the primary processor. The logic also causes the tracing coprocessor to initiate logging, into an execution trace, at least a memory cell data value consumed by the primary processor in connection with execution of at least one executable code instruction.