[Cranelift] resolves #13306, delete extend/reduce rule#13031
Merged
cfallin merged 1 commit intobytecodealliance:mainfrom Apr 10, 2026
Merged
[Cranelift] resolves #13306, delete extend/reduce rule#13031cfallin merged 1 commit intobytecodealliance:mainfrom
cfallin merged 1 commit intobytecodealliance:mainfrom
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[Cranelift] filetest error fix
cfallin
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Apr 10, 2026
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Cause
This regression was caused by the
ireduce(xext(a) +/- xext(b)) -> a +/- bsimplification rules added incranelift/codegen/src/opts/arithmetic.isle.These rewrites only check that both operands are extended to the same wide type (
cty). They do not verify that the original operand types match the final reduced type (ty), or even match each other.For example, a pattern such as:
ireduce.i32 (iadd.i64 (sextend.i64 x:i16) (uextend.i64 y:i32))can be rewritten into:
iadd.i32 x, ywhich is ill-typed, because
xis stilli16while the new instruction expects both operands to bei32.This matches the verifier failure we observed.
Resolution
We decided to remove these rules for now.
Thanks for reporting this issue.