Pipelined architecture with separate pre-fetch and instruction fetch stages
AssigneeFaraday Technology Corp.
InventorHung-Yu Lin
Life of this patent
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AssigneeFaraday Technology Corp.
InventorHung-Yu Lin
Estimating the term…
pipelined CPU includes a pre-fetch (PF) stage for performing branch prediction, and an instruction fetch (IF) stage for fetching instructions that are to be later processed by an execution (EX) stage. The PF stage has a PF address (PFA) register for storing the address of an instruction being processed by the PF stage, and the IF stage has an IF address (IFA) register for storing the address of an instruction to be fetched for later execution. The CPU also includes address register control (ARC) circuitry for setting the contents of the PFA and the IFA. The ARC accepts branch-prediction results from the PF stage to determine the subsequent contents of the PFA and the IFA. If the PF stage predicts no branching, then the ARC sets a next address of the PFA to be sequentially after a current address of the PFA, and sets a next address of the IFA be the current address of the PFA. If the PF stage predicts a branch, then the ARC sets the next address of the PFA to be sequentially after a predicted branch address, and sets the next address of the IFA be the predicted branch address.
A pipelined central processing unit (CPU) comprising:
A method for pipelining instructions in a central processing unit (CPU), the method comprising:
Dependencies are inferred from the claim text.