Memory conflict buffer for achieving memory disambiguation in compile-time code schedule

Wen-Mei W Hwu (Inventor), Tokuzo Kiyohara (Inventor), William Chen (Inventor)

Research output: Patent

Abstract

An apparatus is provided, for use in a computer having a register bank and a device for operand fetch and instruction execution, for monitoring a store address to maintain coherency of preloaded data that is fetched by a load operation and should be effected by at least one subsequent store operation. The apparatus includes an address register bank having entries for holding the address of a load having loaded data which should be affected by at least one subsequent store operation. Each of the entries has associated therewith a pre-load flag and a type field, the pre-load flag being set when the load is executed and reset when there is no need to be affected by a subsequent store operation. The apparatus is further configured to compare the address held in the register bank with the address of a subsequent store operation in consideration of the access type held in the type of field when the pre-load flag is set, and to reset the pre-load flag when special operation which terminate monitoring addresses are detected or the value is updated by non-preload operations. Each of the entries has further associated therewith a retry flag set when the preloaded data is invalid and reloading is required at the point of usage.
Original languageEnglish (US)
U.S. patent number5694577
StatePublished - Dec 2 1997

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