On Sun, Nov 4, 2018 at 9:49 PM H.J. Lu <hjl.to...@gmail.com> wrote: > > > > Actually, we can achieve the same with pre-reload splitters. Please > > > > see the attached patch for a couple of examples and a fix for > > > > vbroadcastss that accesses the memory in wrong mode. > > > > > > > > > > My patch removes a bunch of duplicated patterns from sse.md. But > > > yours adds a couple more patterns. Isn't fewer patterns preferred? > > > > Playing SUBREG games before reload does not look safe to me. We would > > There are plenty of SUBREG usage in i386 backend before preload. It is > perfectly safe to do so as long as we don't create SUBREG with a different > register class from the base. Do you have a testcase to show my SUBREG > usage is unsafe?
No. However, the patch then substatially changes functionality in the vector part of the i386 (expand_vec_perm_1), so it needs approval from the relevant maintainer (Kirill). Uros.
