extern int test_hard_reg_class (enum reg_class rclass, rtx x);
extern int jump_over_one_insn_p (rtx_insn *insn, rtx dest);
-extern int avr_hard_regno_mode_ok (int regno, machine_mode mode);
extern void avr_final_prescan_insn (rtx_insn *insn, rtx *operand,
int num_operands);
extern int avr_simplify_comparison_p (machine_mode mode,