Patent ID: 11797309

Abstract:
An apparatus and method for tracking speculative execution flow and detecting potential vulnerabilities. For example, one embodiment of a processor comprises: an instruction fetcher to fetch instructions from a cache or system memory; a branch predictor to speculate a first instruction path to be taken comprising a first sequence of instructions; a decoder to decode the first sequence of instructions; execution circuitry to execute the first sequence of instructions and process data associated with the instruction to generate results; information flow tracking circuitry and/or logic to: assign labels to all or a plurality of instructions in the first sequence of instructions, track resource usage of the plurality of instructions using the labels, merge sets of labels to remove redundancies; and responsive to detecting that the first instruction path was mis-predicted, generating one or more summaries comprising resources affected by one or more of the first sequence of instructions; and recycling labels responsive to retirement of instructions associated with the labels.