[PATCH] D130164: [LV] Support predicated div/rem operations via safe-divisor select idiom

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

On targets with a vector "div" instruction, the instruction never actually traps or otherwise misbehaves; the only reason we have an issue here is that the IR "sdiv" is defined to be instant UB.  Maybe we could consider introducing a new IR operation to model this?  Maybe it doesn't really matter, though; division is expensive enough that the cost of an extra "select" is probably insignificant.

> Not thinking about it real hard, int_max/uint_max might be reasonable.

That doesn't work for srem; the absolute value of int_min is larger than int_max.


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  https://reviews.llvm.org/D130164/new/

https://reviews.llvm.org/D130164