1 --- gcc/gcc/tree-vrp.c 29 Jul 2005 15:21:54 -0000 2.47
2 +++ gcc/gcc/tree-vrp.c 30 Jul 2005 18:10:26 -0000
3 @@ -908,7 +908,7 @@ vrp_int_const_binop (enum tree_code code
8 + if (flag_wrapv || TYPE_UNSIGNED (TREE_TYPE (val1)))
9 return int_const_binop (code, val1, val2, 0);
11 /* If we are not using wrapping arithmetic, operate symbolically
12 @@ -1095,6 +1095,22 @@ extract_range_from_binary_expr (value_ra
13 the same end of each range. */
14 min = vrp_int_const_binop (code, vr0.min, vr1.min);
15 max = vrp_int_const_binop (code, vr0.max, vr1.max);
17 + /* Check for possible unsigned wrapping. */
18 + if (code == PLUS_EXPR && TYPE_UNSIGNED (TREE_TYPE (expr)))
20 + tree res0 = fold_binary_to_constant (GT_EXPR, TREE_TYPE (expr),
22 + tree res1 = fold_binary_to_constant (GT_EXPR, TREE_TYPE (expr),
25 + if ((res0 && integer_onep (res0))
26 + || (res1 && integer_onep (res1)))
28 + set_value_range_to_varying (vr);
33 else if (code == MULT_EXPR
34 || code == TRUNC_DIV_EXPR
35 @@ -1204,6 +1221,22 @@ extract_range_from_binary_expr (value_ra
37 min = vrp_int_const_binop (code, vr0.min, vr1.max);
38 max = vrp_int_const_binop (code, vr0.max, vr1.min);
40 + /* Check for possible unsigned wrapping. */
41 + if (TYPE_UNSIGNED (TREE_TYPE (expr)))
43 + tree res0 = fold_binary_to_constant (LT_EXPR, TREE_TYPE (expr),
45 + tree res1 = fold_binary_to_constant (GT_EXPR, TREE_TYPE (expr),
48 + if ((res0 && integer_onep (res0))
49 + || (res1 && integer_onep (res1)))
51 + set_value_range_to_varying (vr);
58 @@ -1677,6 +1710,10 @@ compare_ranges (enum tree_code comp, val
59 else if (cmp_min != -2 && cmp_max != -2)
60 return boolean_false_node;
62 + /* If [V0_MIN, V1_MAX] < [V1_MIN, V1_MAX] then V0 != V1. */
63 + else if (compare_values (vr0->min, vr1->max) == 1
64 + || compare_values (vr1->min, vr0->max) == 1)
65 + return boolean_false_node;