SWAPPING AND RESTORING CONTEXT-SPECIFIC BRANCH PREDICTOR STATES ON CONTEXT SWITCHES IN A PROCESSOR

摘要

Swapping and restoring context-specific branch predictor states on context switches in a processor. A branch prediction circuit in an instruction processing circuit of a processor includes a private branch prediction memory configured to store branch prediction states for a context of a process being executed. The branch prediction states are accessed by the branch prediction circuit to predict outcomes of its branch instructions of the process. In certain aspects, when a context switch occurs in the processor, branch prediction states stored in a private branch prediction memory and associated with the current, to-be-swapped-out context, are swapped out of the private branch prediction memory to the shared branch prediction memory. Branch prediction states in the shared branch prediction memory previously stored (i.e., swapped out) and associated with to-be-swapped-in context for execution are restored in the private branch prediction memory to be used for branch prediction.