https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79131
--- Comment #1 from Vladimir Makarov <vmakarov at gcc dot gnu.org> --- This is a bug in LRA now. LRA should have reloaded the destination or the operand as they conflicts in insn 31 (the destination is an early clobbered operand). IRA does not take early clobbers into account as they are usually insn alternative specific and IRA can not predict the final alternative. So dealing with such cases is LRA responsibility. The input operand is a paradoxical subreg and probably LRA does not behave correctly for big-endian targets. Probably the fix will need more time than for pr79058 but I hope to fix it on this week.