re PR middle-end/80422 (ICE on valid code at -O3 in 32-bit mode on x86_64-linux-gnu: in operator[], at vec.h:732)

	PR middle-end/80422
	* cfgcleanup.c (try_crossjump_to_edge): Verify SRC1 and SRC2 have
	predecessors after walking up the insn chain.

	PR middle-end/80422
	* gcc.c-torture/compile/pr80422.c: New test.

From-SVN: r246975