diff options
Diffstat (limited to 'gcc/match.pd')
| -rw-r--r-- | gcc/match.pd | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/gcc/match.pd b/gcc/match.pd index f08ab67..e731bdb 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -3993,6 +3993,24 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (if (single_use (@2)) (cmp @0 @1))))) +/* Simplify (x < 0) ^ (y < 0) to (x ^ y) < 0 and + (x >= 0) ^ (y >= 0) to (x ^ y) < 0. */ +(for cmp (lt ge) + (simplify + (bit_xor (cmp:s @0 integer_zerop) (cmp:s @1 integer_zerop)) + (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) + && !TYPE_UNSIGNED (TREE_TYPE (@0)) + && types_match (TREE_TYPE (@0), TREE_TYPE (@1))) + (lt (bit_xor @0 @1) { build_zero_cst (TREE_TYPE (@0)); })))) +/* Simplify (x < 0) ^ (y >= 0) to (x ^ y) >= 0 and + (x >= 0) ^ (y < 0) to (x ^ y) >= 0. */ +(simplify + (bit_xor:c (lt:s @0 integer_zerop) (ge:s @1 integer_zerop)) + (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) + && !TYPE_UNSIGNED (TREE_TYPE (@0)) + && types_match (TREE_TYPE (@0), TREE_TYPE (@1))) + (ge (bit_xor @0 @1) { build_zero_cst (TREE_TYPE (@0)); }))) + /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the signed arithmetic case. That form is created by the compiler often enough for folding it to be of value. One example is in |