I64ToI32Lowering: Document non-trapping float truncation behavior. NFC - #9022
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tlively
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Aug 19, 2026
… (NFC) Document that `I64ToI32Lowering` is designed for the `wasm2js` pipeline and does not preserve strict WebAssembly trapping semantics for float-to-int conversions. Also add comments in `lowerTruncFloatToInt` noting that the emitted 32-bit truncations are translated to JavaScript bitwise operations in `wasm2js` and thus do not trap on out-of-range values, NaN, or infinity. See: #9017
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Document that
I64ToI32Loweringis designed for thewasm2jspipeline and does not preserve strict WebAssembly trapping semantics for float-to-int conversions.Also add comments in
lowerTruncFloatToIntnoting that the emitted 32-bit truncations are translated to JavaScript bitwise operations inwasm2jsand thus do not trap on out-of-range values, NaN, or infinity.See: #9017