> I noticed similar issue when analyzing the SPEC, self-recursive function is > not versioned and posted my observations in > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92074.
> Generally, this could be implemented well by your patch, while I am > wondering whether it is OK to convert the recursive function to > non-recursive function in a independent pass after ipa-cp and ipa-sra instead > of reuse the ipa-cp framework? > The reason is sometimes the argument is passed-by-reference, and > ipa-sra runs after ipa-cp, so this kind of optimization may not be done in > WPA. What's your idea about this, please? Thanks. Function versioning is done in ipa-cp, there is nothing special for recursive function. So adding a dedicated pass for recursive seems to be redundant. We might not need to resort to ipa-sra to resolve concern you mentioned. Original ipa-cp already supports a simple kind of propagation on by-ref argument, who must be defined by constant. And for an extended form as: *arg = *param OP constant, I've created a tracker PR91682, also composed a patch: https://gcc.gnu.org/ml/gcc-patches/2019-09/msg01189.html. Feng
