Patent ID: 6851040

Claim:
A method for implementing a segmentation operation comprising the steps of: providing a first segment selector for deriving a linear address of a segment descriptor in a first descriptor table, providing a second segment selector for deriving a linear address of a segment descriptor in a second descriptor table, attempting an access of the first descriptor table to derive a segment descriptor, attempting an access of the second descriptor table to derive a segment descriptor if the access of the first descriptor table fails, and storing a derived segment descriptor from a successful attempted access in a descriptor register; and wherein any attempt to access is divided into discrete sub-steps comprising: checking properties of a logical address to determine whether those properties are consistent with the criteria for addressing one of the first and the second descriptor tables in a first discrete sub-step of deriving a linear address, and performing a base-add operation to determine the linear address as a second discrete sub-step of deriving a linear address.