Fold wide mask reductions with a bitwise op instead of short-circuiting - #343
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For masks wider than the native register, any/all_true/false now combine the split halves with `or`/`and` and do a single horizontal aggregation, rather than aggregating each half and joining with `||`/`&&`. This trades away early-exit on the first half for one lane-wise vector op plus one scalar extraction, which is the cheaper path in practice.
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Thank you! I'll try to take a look tomorrow. Is this a fix for #342 or is this unrelated? |
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Unrelated |
Shnatsel
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Aug 23, 2026
Shnatsel
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Shnatsel
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Looks good to me, thank you!
llvm-mca agrees this is beneficial on both AVX2 and NEON.
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For masks wider than the native register, any/all_true/false now combine the split halves with
or/andand do a single horizontal aggregation, rather than aggregating each half and joining with||/&&.This trades away early-exit on the first half for one lane-wise vector op plus one scalar extraction, which is the cheaper path in practice.