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[Performance] Short-circuit NodeComparator::areNodesEqual before printing - #8752
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…ting Bail out early in areNodesEqual() before the expensive printWithoutComments() call: - return false when either node is null (also avoids printing a null node) - return false when the two single nodes are of a different class, since nodes of different classes can never print as equal This skips the print+compare round-trip on the common unequal case.
TomasVotruba
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Adds two cheap early bail-outs to
areNodesEqual()before the expensiveprintWithoutComments()round-trip:falsewhen either node isnull- also avoids calling the printer on a null nodefalsewhen the two single nodes are of a different class - nodes of different classes can never print as equal, so the print+compare is pure overheadBehavior is unchanged; only the common unequal case gets faster.
Benchmark
bench/node_comparator_short_circuit_bench.php- 1.8M calls over a realistic blend of pair types (null, different-class, same-class equal/unequal), CPU time (user+sys), warmup excluded, 3 runs each branch:~1.69x faster, ~41% CPU cut on this blend (5 of 9 pairs now skip the print). The win scales with how many hot-path pairs are null or different-class; same-class pairs are unchanged.