https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78669
Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC|segher at gcc dot gnu.org |vmakarov at gcc dot gnu.org --- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> --- The insn 125 is removed in earlier iteration of the combine_and_move_insns loop, when processing regno 119, insn 25 is deleted: remove_death (regno, use_insn); SET_REG_N_REFS (regno, 0); REG_FREQ (regno) = 0; delete_insn (def_insn); So, I think either combine_and_move_insns should not assert there are still some non-debug uses and instead just do partly what it does if it replaces the uses of regno in use_insn with the equiv replacement, or when deleting some def_insn it should also adjust the uses, or we should just continue if we find replaceable regs without any uses.