Use LLVM intrinsics for NaN-propagating float min and max#5114
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SeanTAllen merged 1 commit intomainfrom Apr 4, 2026
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Use LLVM intrinsics for NaN-propagating float min and max#5114SeanTAllen merged 1 commit intomainfrom
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The conditional implementation (`if this < y then this else y end`) is asymmetric when NaN is involved: IEEE 754 comparisons with NaN return false, so the else branch always fires when `this` is NaN but not when `y` is NaN. The result depends on argument order, which is wrong. LLVM's `llvm.minimum`/`llvm.maximum` intrinsics implement IEEE 754-2019 NaN-propagating semantics — if either operand is NaN, the result is NaN. Closes #5089
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F32/F64
min/maxusedif this < y then this else y end, which is asymmetric with NaN. IEEE 754 comparisons involving NaN returnfalse, so theelsebranch always fires whenthisis NaN but not whenyis NaN —NaN.min(5.0)returned5.0butF32(5.0).min(NaN)returnedNaN.Replaced with LLVM
llvm.minimum/llvm.maximumintrinsics which implement IEEE 754-2019 NaN-propagating semantics: if either operand is NaN, the result is NaN. Integermin/maxare unchanged.Closes #5089