Optimize localify (regalloc onto locals): - #20
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- Use a bitset rather than a HashSet for the live-set fixpoint computation; - Use a dense index space consisting *only* of block-crossing values for those bitsets, to keep them smaller; - Use a local dense liveset datastructure that uses epoch-numbers-per-slot to allow O(1) clearing between blocks. Overall, speeds up compilation on a very large input from ~173 seconds to ~7 seconds.
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fitzgen
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Jul 27, 2026
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LGTM modulo nitpicks below.
Seems like this crate would benefit from pulling in cranelift_entity in general, but I understand that is a larger change.
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Overall, speeds up compilation on a very large input from ~173 seconds to ~7 seconds.