| CPC G06F 12/1009 (2013.01) [G06F 12/1027 (2013.01)] | 3 Claims | 

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               1. A virtual memory circuitry that encodes a virtual address (VA) in a VA memory for four different page sizes in a main memory, with a virtual page number encoded in settable bitfields of the VA, 
            wherein page size PS is implicit in the VA according to which bits in the VA are zeros, 
                multiple page table registers for separate address spaces; 
                a first page table that is a subpage of a 16 MB page in the main memory, wherein the first page table is a contiguous block of N×64 KB physical pages with N×213×8-byte entries, and 
                the virtual memory circuitry selecting, using an address space (AS) field, a page table register among the page table registers, which stores a physical page table number and its size. 
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