https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126904
--- Comment #3 from Aldy Hernandez <aldyh at gcc dot gnu.org> --- (In reply to Richard Biener from comment #2) > spin () might not return, so PRE drops all possibly trapping expressions > from getting upward during dataflow (and if course it does not track > "trapping" in any fancy way). VN itself doesn't care, the issue there > is the merge PHI for the t = 2 VDEF. So it would need PRE, but see above, > even looping const/pure functions can not "exit". > > DOMs memory walking handling is nice in the way it works as it knows before > even starting that there's a dominating syntactic equivalent expression > (also solving the trapping issue). I believe I’ve addressed all the backward’s threader limitations, what remains are either cost basis things which Richard has taken, or the PRE/FRE/VN issue in this PR. Richard, do you have any plans here? It’d be nice if we could disable the DOM threader this release, but I understand everyone’s busy with their own thing.
