PR middle-end/44071

	* cfglayout.c (fixup_reorder_chain): Allow asm goto to have
	no fallthru edge.
	* cfgcleanup.c (try_optimize_cfg): When in cfglayout mode
	optimizing away empty bb with no successors, move over its
	footer chain to fallthru predecessor.
	* cfgrtl.c (patch_jump_insn): Update also REG_LABEL_OPERAND.
	(rtl_split_edge): For asm goto call patch_jump_insn even if
	splitting fallthru edge.

	* c-c++-common/asmgoto-4.c: New test.
	* gcc.target/i386/pr44071.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@159288 138bc75d-0d04-0410-961f-82ee72b054a4