https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62173
--- Comment #25 from amker at gcc dot gnu.org --- (In reply to Jiong Wang from comment #24) > (In reply to amker from comment #23) > > partially agree. > > at least for the single use case given by Seb, I think tree ivopt should do > it. (I verified clang do ivopt correctly for the case) > > for the rtl re-associate, it's a little bit painful from my experiment > experiences. as it's not always good to reassociate virtual_frame + offset, > we can only benefit if it's in loop, because the re-associate will increase > register pressure, there will be situations that more callee-saved regs > used, and finally we run into unncessary push/pop in pro/epilogue... and I > haven't found a good place where we can safely re-use existed rtl info and > do the rtl re-association as I am afraid rebuild those rtl info will cause > compile time penalty. Yes, The ivopt's issue that it doesn't treat "A[d]" as an address type iv use should be fixed anyway.
