re PR tree-optimization/68583 (Missed if-conversion)

re PR tree-optimization/68583 (Missed if-conversion)

2015-12-09  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/68583
	* tree-if-conv.c (if_convertible_phi_p): Drop
	flag_tree_loop_if_convert_stores check in favor of the
	existing any_mask_load_store check.
	(insert_gimplified_predicates): Likewise.
	(combine_blocks): Likewise.
	(tree_if_conversion): Likewise.
	(ifcvt_memrefs_wont_trap): Properly check
	flag_tree_loop_if_convert_stores in all places that can end
	up introducing store-data-races.
	(if_convertible_gimple_assign_stmt_p): Remove restriction
	on flag_tree_loop_if_convert_stores for stores we can if-convert
	without introducing store-data-races.  Force versioning for
	all if-converted stores.

	* gcc.dg/tree-ssa/ifc-pr68583.c: New testcase.
	* gcc.dg/vect/vect-72.c: Adjust.
	* gcc.dg/vect/vect-cselim-2.c: Likewise.
	* gcc.dg/vect/vect-strided-store-a-u8-i2.c: Likewise.

From-SVN: r231453