re PR rtl-optimization/49235 (ICE: in int_mode_for_mode, at stor-layout.c:424 with -O -fno-delete-null-pointer-checks -fno-tree-scev-cprop -ftree-vectorize -fno-vect-cost-model)

	PR rtl-optimization/49235
	* tree-ssa-address.c (gen_addr_rtx): Ignore base if it is const0_rtx.
	(create_mem_ref_raw): Create MEM_REF even if base is INTEGER_CST.

	* gcc.dg/pr49235.c: New test.

From-SVN: r174478