re PR tree-optimization/46909 (Logical OR expressions are miscompiled)

re PR tree-optimization/46909 (Logical OR expressions are miscompiled)

	PR tree-optimization/46909
	* gimple-fold.c (and_var_with_comparison_1): Save partial
	result even in the is_and case, if both partial results
	are the same, return it.
	(or_var_with_comparison_1): Use is_or predicate instead of
	innercode == TRUTH_OR_EXPR test.  Save partial result
	even in the is_or case, if both partial results are the
	same, return it.  In the !is_or case when both partial
	results are the same, return the partial result instead
	of boolean_true_node.

	* gcc.c-torture/execute/pr46909-1.c: New test.
	* gcc.c-torture/execute/pr46909-2.c: New test.
	* gcc.dg/pr46909.c: New test.

From-SVN: r167800