6.2.4. Branch folding

Branch folding is a technique where, on the prediction of most branches, the branch instruction is completely removed from the instruction stream presented to the execution pipeline. Branch folding can significantly improve the performance of branches, taking the CPI for branches significantly below 1.

When the PU prefetches a predicted taken instruction, it evaluates if the branch:

If all of the conditions are met, the branch is folded on the subsequent prefetches of the branch.

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