Ensure other cases of lzcnt/tzcnt/popcount are handled by rangecheck#128620
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Ensure other cases of lzcnt/tzcnt/popcount are handled by rangecheck#128620tannergooding wants to merge 2 commits into
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Pull request overview
This change updates JIT range analysis (RangeCheck::GetRangeFromAssertionsWorker) to recognize additional lzcnt/tzcnt/popcount value-numbering function cases and to tighten the inferred constant upper bound from a fixed 64 to 32 or 64 depending on bit-width.
Changes:
- Adds target-conditional switch cases intended to cover additional xarch/arm64 LZCNT/TZCNT/POPCNT-related VN function IDs.
- Adjusts the inferred upper bound for
{LeadingZeroCount, TrailingZeroCount, PopCount}from a constant64to32vs64based on type.
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EgorBo
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May 27, 2026
EgorBo
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May 27, 2026
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