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:
Oct. 26, 2010
Filed:
Jan. 21, 2003
David W Flynn, Cambridge, GB;
David J Seal, Cambridge, GB;
Wilco Dijkstra, Cambridge, GB;
Michael R Nonweiler, Cambridge, GB;
David W Flynn, Cambridge, GB;
David J Seal, Cambridge, GB;
Wilco Dijkstra, Cambridge, GB;
Michael R Nonweiler, Cambridge, GB;
ARM Limited, Cambridge, GB;
Abstract
The present invention provides a technique for swapping data values within a data word. In particular, a single endian reverse instruction is provided to cause independent swap operations to be performed on particular sections of an input data word. The data processing apparatus of the present invention comprises a data processing unit for executing instructions which is responsive to the endian reverse instruction to apply an endian reverse operation to an input data word Rm comprising a plurality of data values. The endian reverse operation yields a result data word Rd given by: treating the input data word as consisting of a plurality of input sections, the result data word having a corresponding plurality of result sections, at least one input section comprising a plurality of data values; and for at least one of the input sections comprising a plurality of data values, performing an independent swap operation on the data values within that input section to form the result data word Rd in which the corresponding result section has its data values swapped with respect to that input section. This provides a particularly efficient technique for providing endian reversal functionality within a data processing apparatus supporting a variety of data structures, such as packed halfwords, zero extended halfwords, sign extended halfwords, etc.