https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78516
--- Comment #16 from Peter Bergner <bergner at gcc dot gnu.org> --- (In reply to Vladimir Makarov from comment #15) > Sorry, I applied your changes manually and did a typo. The line > > SET_SRC (curr_insn_set) = new_reg; > > should be removed. > > I tested this patch with the typo on x86-64 and no new failures occurred. > Strange. That would suggest on x86-64, SET_SRC (curr_insn_set) is never a subreg for the insns that we process here. As they say, better to be lucky than good! :-) With the SPE, we're just not lucky as shown by Joseph's last run. I'm sure it will pass after removing the unwanted line above.