System for reducing number of lookups in a branch target address cache by storing retrieved BTAC addresses into instruction cache

摘要

A technique for reducing lookups to a branch target address cache (BTAC) is disclosed. In this technique, a branch target address is retrieved from the BTAC in response to a miss in looking up an instruction address in an instruction cache (I-cache). The branch target address is associated with the instruction address. The branch target address retrieved from the BTAC is stored in the I-cache. With this disclosed technique, subsequent instruction addresses are looked up in the I-cache, nonparallel to the BTAC, thus saving power by reducing needless BTAC lookups.