tree-ssa-structalias.c (build_succ_graph): Feed stores to anything only to variables that can take pointers.

2009-11-07  Richard Guenther  <rguenther@suse.de>

	* tree-ssa-structalias.c (build_succ_graph): Feed stores
	to anything only to variables that can take pointers.
	(get_constraint_for_ssa_var): Properly exclude full
	variables from expanding.
	(first_vi_for_offset): Avoid overflow in arithmetic.
	(first_or_preceding_vi_for_offset): Likewise.
	(count_num_arguments): Fix implementation.
	(gate_ipa_pta): Do not run when not optimizing.

From-SVN: r154002