re PR rtl-optimization/46777 (ICE: in rtl_verify_flow_info, at cfgrtl.c:2164 with -O -fgcse -fno-tree-dominator-opts -funroll-loops)

	PR rtl-optimization/46777
	* cfglayout.c (duplicate_insn_chain): Avoid duplicating
	also barrier after tablejump.

	* gcc.dg/pr46777.c: New test.

From-SVN: r167513