https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69614
--- Comment #19 from Bernd Schmidt <bernds at gcc dot gnu.org> --- (In reply to Jakub Jelinek from comment #16) > insn 146 is the pre-reload first xor, insn 701 is storing of the result into > the [sp, #16] memory slot, but the insn 659 inserted during LRA is just > weird. > There is no corresponding clobber in *.ira at this point This is left over from an intermediate state in LRA, where we create a new TImode pseudo in split_if_necessary. Essentially (you probably have different register numbers): (set (subreg:SI (reg:TI 207) 0) something) ;; inserted by LRA, expanded into a four-move sequence starting with a clobber (set (newreg:TI) (reg:TI 207)) (call ...) ;; inserted by LRA, similar four-move plus one clobber (set (reg:TI 207) (newreg:TI)) (set (subreg:SI (reg:TI 207) 4) something else Later we remove these moves again, leaving only the clobbers around. I'm not sure yet whether the clobbers have any bad effect or whether something else is going on.
