* flow.c (proagate_one_insn): Remove useless assignment.
	* jump.c (delete_insn): Tidy.
	* loop.c (try_copy_prop): When deleting an instruction with a
	REG_RETVAL note, delete the entire libcall sequence.
	(loop_delete_insns): New function.
	* unroll.c (initial_reg_note_copy): Copy INSN_LIST notes, even if
	we're not substituting into them yet.

From-SVN: r41486