1. A computer system for confidence threshold-based opposing path execution for branch prediction, the system comprising: a processor, the processor configured to perform a method comprising: determining a branch prediction for a first branch instruction that is encountered during execution of a first thread, wherein the branch prediction indicates a primary path and an opposing path for the first branch instruction; executing the primary path by the first thread; determining a confidence of the branch prediction; comparing the confidence of the branch prediction to a confidence threshold; and based on the confidence of the branch prediction being less than the confidence threshold, starting a second thread that executes the opposing path of the first branch instruction, wherein the second thread is executed in parallel with the first thread.