llvm-project

313a33b9 - [InstCombine] Reduce nested logical operator if poison is implied (#86823)

[InstCombine] Reduce nested logical operator if poison is implied (#86823) Fixes #76623 Alive2 proof: https://alive2.llvm.org/ce/z/gX6znJ (I'm not sure how to write a proof for such transform, maybe there are mistakes) In most cases, `icmp(a, C1) && (other_cond && icmp(a, C2))` will be reduced to `icmp(a, C1) & (other_cond && icmp(a, C2))`, since latter icmp always implies the poison of the former. After reduction, it's easier to simplify the icmp chain. Similarly, this patch does the same thing for `(A && B) && C --> A && (B & C)`. Maybe we could constraint such reduction only on icmps if there is regression in benchmarks.