7.5.4 More Instructions

Supporting new instructions in the pipelined processor is much like supporting them in the single-cycle processor. However, new instructions may introduce hazards that must be detected and solved.

In particular, supporting addi and j instructions in the pipelined processor requires enhancing the controller, exactly as was described in Section 7.3.3, and adding a jump multiplexer to the datapath after the branch multiplexer. Like a branch, the jump takes place in the Decode stage, so the subsequent instruction in the Fetch stage must be flushed. Designing this flush logic is left as Exercise 7.35.

7.5.5 Performance Analysis

The pipelined processor ideally would have a CPI of 1, because a new instruction is issued every ...

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