search for: d28934

> I'm not necessarily sympathetic to the idea of adding another canonicalization pass only for this purpose. The problem is that as you said, SimplifyCfg does all sorts of stuff, and I suspect is not the fastest pass in the world. Also, in the case that annoys me, there is an LCSSA pass in the middle, and I suspect it would be a better idea to only do the LCSSA etc. transform again if no

...should be linear. Currently it's not because it uses the SSA > updater which computes dominance frontiers, so it might get O(N^3). > The alternative SSAupdater proposed solves this problem using the > novel algorithm from Braun et al. linked in the review > https://reviews.llvm.org/D28934 > It still has the problem that if leaves redundant phis around at the > beginning of the block, e.g. > > %patatino1 = phi [ %tinky, %somebb, %winky, %someotherbb ] > %patatino2 = phi [ %tinky, %somebb, %winky, %someotherbb ] > > The current SSA updater pays a (sometimes high)...