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…ndant-collapsing processFilter unconditionally set flagsEnum.Filter on its input, which blocked the descendant-collapsing optimization in processAxis: //element[@attr] compiled to childQuery{Input: descendantQuery{}} instead of the more efficient descendantQuery{name:"element"}. The Filter flag is only load-bearing for positional predicates (numeric literals, position(), last(), arithmetic) where mergeQuery restructuring is needed to give correct "first per parent" semantics for //table[1]. For non-positional predicates like //a[@href] or //div[@Class="x"] the flag serves no purpose. This change adds positionalCondition(), a lightweight AST walk that inspects the raw condition node before compilation, and gates the flag on its result. Non-positional predicates now resolve to a single descendantQuery, reducing allocations by ~70% and execution time by ~57% on a representative 430-node document. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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processFilteralways setflagsEnum.Filteron its input, which blocked the descendant-collapsing optimization inprocessAxis.//element[@attr]compiled tochildQuery{Input: descendantQuery{}}instead of the more efficientdescendantQuery{name:"element"}. The Filter flag is only needed for positional predicates where mergeQuery restructuring is needed, like for//table[1]. For non-positional predicates like//a[@href]we can drop the flag.This change adds
positionalCondition(), a lightweight AST walk that inspects the raw condition node before compilation, and gates the flag on its result. Non-positional predicates now resolve to a singledescendantQuery. Added a unit test for the new function.Benchmarking (bench functions included) showed significant time and alloc reductions for non-positional filters, and no change for positional filters.
This PR contains code written by Claude (Sonnet 4.6).