Replacer Submodule Documentation

The PLRU update algorithm is adopted. Considering that instruction fetches may access continuous doublelines, two replacers are set up for odd and even addresses. When performing touch and victim, the replacer is updated separately based on the parity of the address.

PLRU Algorithm Diagram

touch

The Replacer has two touch ports to support double lines. Based on the address parity of the touch request, it is assigned to the corresponding replacer for updating.

victim

The Replacer has only one victim port because only one MSHR will write to the SRAM at a time. Similarly, based on the address parity, the waymask is obtained from the corresponding replacer. A touch operation is then performed in the next cycle to update the replacer.