re PR tree-optimization/51938 (missed optimization: 2 comparisons)

re PR tree-optimization/51938 (missed optimization: 2 comparisons)

2012-08-06 Marc Glisse <marc.glisse@inria.fr>

gcc/
	PR tree-optimization/51938
	PR tree-optimization/52005
	* tree-ssa-ifcombine.c (ifcombine_ifandif): New parameters for
	inverted conditions.
	(ifcombine_iforif): Remove, merge code into ifcombine_ifandif.
	(tree_ssa_ifcombine_bb): Update calls to the above. Detect !a&&b
	and !a||b patterns.

gcc/testsuite/
	PR tree-optimization/51938
	PR tree-optimization/52005
	* gcc.dg/tree-ssa/ssa-ifcombine-8.c: New testcase.
	* gcc.dg/tree-ssa/ssa-ifcombine-9.c: Likewise.
	* gcc.dg/tree-ssa/ssa-ifcombine-10.c: Likewise.
	* gcc.dg/tree-ssa/ssa-ifcombine-11.c: Likewise.

From-SVN: r190184