The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 11, 1997
Filed:
Feb. 06, 1996
Albert J Loper, Cedar Park, TX (US);
Soummya Mallick, Austin, TX (US);
Michael Putrino, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method for selectively executing speculative load instructions in a high-performance processor is disclosed. In accordance with the present disclosure, when a speculative load instruction for which the data is not stored in a data cache is encountered, a bit within an enable speculative load table which is associated with that particular speculative load instruction is read in order to determine a state of the bit. If the associated bit is in a first state, data for the speculative load instruction is requested from a system bus and further execution of the speculative load instruction is then suspended to wait for control signals from a branch processing unit. If the associated bit is in a second state, the execution of the speculative load instruction is immediately suspended to wait for control signals from the branch processing unit. If the speculative load instruction is executed in response to the control signals, then the associated bit in the enable speculative load table will be set to the first state. However, if the speculative load instruction is not executed in response to the control signals, then the associated bit in the enable speculative load table is set to the second state. In this manner, the displacement of useful data in the data cache due to wrongful execution of the speculative load instruction is avoided.