re PR target/50447 ([avr] Better support of AND, OR, XOR and PLUS with constant integ...

re PR target/50447 ([avr] Better support of AND, OR, XOR and PLUS with constant integers for 16- and 32-bit values)

	PR target/50447
	* config/avr/avr.md: (adjust_len): Add alternative "out_plus".
	(addsi3): Rewrite using QI scratch register.  Adjust text
	peepholes using plus:SI.
	(*addsi3_zero_extend.hi): New insn.
	(*subsi3_zero_extend.hi): New insn.
	(*subhi3_zero_extend1): Set attribute "cc" to "set_czn".
	(*subsi3_zero_extend): Ditto.
	(subsi3): Change predicate #2 to register_operand.
	* config/avr/avr-protos.h (avr_out_plus): New prototype.
	(avr_out_plus_1): New static function.
	(avr_out_plus): New function.
	(adjust_insn_length): Handle ADJUST_LEN_OUT_PLUS.

From-SVN: r179123