Abstract: Scan logic which tracks the relative age of stores with respect to a particular load (or of loads with respect to a particular store) allows at processor to hold younger stores until the completion of older loads (or to hold younger loads until completion of older stores). Embodiments of propagate-kill style lookahead scan logic or of tree-structured, hierarchically-organized scan logic constructed in accordance with the present invention provide store older and load older indications with very few gate delays, even in processor embodiments adapted to concurrently evaluate large numbers of operations. Operating in conjunction with the scan logic, address matching logic allows the processor to more precisely tailor its avoidance of load-store (or store-load) dependencies.

Abstract: Scheduler logic which tracks the relative age of stores with respect to a particular load (and of loads with respect to a particular store) allows a load-store execution controller constructed in accordance with the present invention to hold younger stores until the completion of older loads (and to hold younger loads until completion of older stores). Address matching logic allows a load-store execution controller constructed in accordance with the present invention to avoid load-store (and store-load) dependencies. Propagate-kill scan chains supply the relative age indications of loads with respect to stores (and of stores with respect to loads).