Use dense fetches in Query::get and Query::iter_many#12501
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james7132 wants to merge 1 commit intobevyengine:mainfrom
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Use dense fetches in Query::get and Query::iter_many#12501james7132 wants to merge 1 commit intobevyengine:mainfrom
james7132 wants to merge 1 commit intobevyengine:mainfrom
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alice-i-cecile
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Mar 17, 2024
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Looks fine to me, pending neutral-to-positive microbenchmarks.
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Objective
Found while investigating #12476 and #12474. Apparently the Rust compiler cannot optimize out the archetype fetch if it's not used by the fetch type in
QueryState::get_unchecked_manual.Solution
Use the same technique for branching on constants to use dense fetches instead of archetypal fetches. The generated assembly confirms that there's one less memory access for calls to
Query::geton dense queries.Performance
TODO: Microbenchmark