Eine Übersetzungs-Querzuordnungs-Puffer-Organisation mit variabler Seitengrößenabbildung und Opfer-Cache-Speicherung

摘要

A translation look-aside buffer (TLB) (10) for translating a variable page size virtual page number (VIRTUAL ADDRESS) to a physical page number (PHYSICAL ADDRESS) partitions the virtual page number into an upper portion (UPPER) and a lower portion (LOWER). The upper portion is always compared to an upper virtual page number entry in a first content addressable memory (14) while only certain bits of the lower portion are selectively compared to a corresponding number of bits in a lower virtual page number entry in a second content addressable memory (16). The number of bits compared in the second content addressable memory is determined by the specified size of the physical page. The TLB includes a page size memory (18) having a plurality of page size entries wherein the certain number of bits for each of the lower virtual page entries is specified by a corresponding page size entry. Associated with each bit in the lower virtual page number entries is an enable transistor for selectively enabling the comparison of that bit in the lower virtual page number entry, in dependence on the corresponding bit in the page size entry. A victim TLB can be coupled to the main TLB (10) in order to improve the overall hit rate of the combined TLBs. <IMAGE>