* verify.cc (state::enter_subroutine): New method.

	(handle_jsr_insn): Use it.
	(state::merge): When processing a `ret', correctly use
	subroutine's state to determine which local variables have
	changed.
	(push_exception_jump): Don't let stack overflow.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@49388 138bc75d-0d04-0410-961f-82ee72b054a4