https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88788
--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> --- I don't see how that can help. First of all, the duplicate SSA_NAMEs don't have to appear just in the same PHI, you can have them in multiple different PHIs too. And, you can have loops there as well, either directly (e.g. a PHI result where one or more arguments of the PHI is equal to the PHI result), or indirectly. So, you probably need to remember the outcome of calling the function on some SSA_NAME already before, and you need to deal with the loops somehow (ignore back edges is one strategy, there are various others, look at other passes).
