| 摘要 |
<p>One or more Shadow Register Files (SRF) are interposed between a Physical Register File (PRF) and a Backing Store (BS) in a shadow register file system. The SRFs comprise dual-port registers connected serially in a chain of arbitrary depth from the PRF. A Register Save Engine has random access to one port of the registers in the final SRF in the chain, and saves/restores data between the final SRF and the BS, e.g., RAM. As PRF registers are deallocated from calling procedures for use by called procedures, data are serially shifted from multi-port registers in the PRF through successive corresponding dual-port registers in SRFs, and are serially shifted back toward the multi-port registers as the PRF registers are reallocated to calling procedures. Since no procedure can access more than the number of registers in the PRF, the effective size of the PRF is increased, using less costly dual-port registers.</p> |
