On Tue, 2 Feb 2016, Richard Biener wrote:
*** gcc/match.pd (revision 233067)
--- gcc/match.pd (working copy)
*************** DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
*** 2094,2099 ****
--- 2094,2117 ----
(bit_and:c (ordered @0 @0) (ordered:c@2 @0 @1))
@2)
+ /* Simple range test simplifications. */
+ /* A < B || A >= B -> true. */
+ (for test1 (lt le ne)
+ test2 (ge gt eq)
+ (simplify
+ (bit_ior:c (test1 @0 @1) (test2 @0 @1))
+ (if (INTEGRAL_TYPE_P (TREE_TYPE (@0))
+ || VECTOR_INTEGER_TYPE_P (TREE_TYPE (@0)))
+ { constant_boolean_node (true, type); })))
+ /* A < B && A >= B -> false. */
+ (for test1 (lt lt lt le ne eq)
+ test2 (ge gt eq gt eq gt)
The lack of symmetry between the || and && cases is surprising. Is there
any reason not to handle the pairs le/ge, le/ne and ge/ne for bit_ior?
+ (simplify
+ (bit_and:c (test1 @0 @1) (test2 @0 @1))
+ (if (INTEGRAL_TYPE_P (TREE_TYPE (@0))
+ || VECTOR_INTEGER_TYPE_P (TREE_TYPE (@0)))
+ { constant_boolean_node (false, type); })))
+
/* -A CMP -B -> B CMP A. */
(for cmp (tcc_comparison)
scmp (swapped_tcc_comparison)
--
Marc Glisse
