search for: pr20997

...i.e., per > bit, with run-time behavior). > > One of the problems this proposal solves is speculation of 'a && b' into > 'a & b'. Currently this is illegal (despite sometimes simplifycfg doing it > anyway). > > It also fixes bugs like http://llvm.org/PR20997 > > > > The proposal doesn't say anything about branching on a poison value. I > assume this should stay as the current interpretation -- that such branches > should be undefined behavior (since we cannot branch to multiple places at > the same time -- even if they would co...

Hello, What follows is my attempt to describe how poison works. Let me know what you think. -- David # LLVM Poison Semantics Poison is an LLVM concept which exists solely to enable further optimization of LLVM IR. The exact behavior of poison has been, to say the least, confusing for users, researchers and engineers working with LLVM. This document hopes to clear up some of the confusion