diff options
Diffstat (limited to 'gcc/tree-vrp.c')
| -rw-r--r-- | gcc/tree-vrp.c | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c index 36e9a3b..1092d17 100644 --- a/gcc/tree-vrp.c +++ b/gcc/tree-vrp.c @@ -236,6 +236,20 @@ set_value_range_to_varying (value_range_t *vr) } +/* Set value range VR to a range of a truthvalue of type TYPE. */ + +static inline void +set_value_range_to_truthvalue (value_range_t *vr, tree type) +{ + if (TYPE_PRECISION (type) == 1) + set_value_range_to_varying (vr); + else + set_value_range (vr, VR_RANGE, + build_int_cst (type, 0), build_int_cst (type, 1), + vr->equiv); +} + + /* Set value range VR to VR_UNDEFINED. */ static inline void @@ -1439,7 +1453,8 @@ extract_range_from_binary_expr (value_range_t *vr, tree expr) } else { - set_value_range_to_varying (vr); + /* The result of a TRUTH_*_EXPR is always true or false. */ + set_value_range_to_truthvalue (vr, TREE_TYPE (expr)); return; } } @@ -1920,7 +1935,8 @@ extract_range_from_comparison (value_range_t *vr, tree expr) set_value_range (vr, VR_RANGE, val, val, vr->equiv); } else - set_value_range_to_varying (vr); + /* The result of a comparison is always true or false. */ + set_value_range_to_truthvalue (vr, TREE_TYPE (expr)); } @@ -4182,6 +4198,7 @@ vrp_visit_phi_node (tree phi) tree lhs = PHI_RESULT (phi); value_range_t *lhs_vr = get_value_range (lhs); value_range_t vr_result = { VR_UNDEFINED, NULL_TREE, NULL_TREE, NULL }; + bool all_const = true; copy_value_range (&vr_result, lhs_vr); @@ -4209,7 +4226,10 @@ vrp_visit_phi_node (tree phi) value_range_t vr_arg; if (TREE_CODE (arg) == SSA_NAME) - vr_arg = *(get_value_range (arg)); + { + vr_arg = *(get_value_range (arg)); + all_const = false; + } else { vr_arg.type = VR_RANGE; @@ -4240,7 +4260,8 @@ vrp_visit_phi_node (tree phi) /* To prevent infinite iterations in the algorithm, derive ranges when the new value is slightly bigger or smaller than the previous one. */ - if (lhs_vr->type == VR_RANGE && vr_result.type == VR_RANGE) + if (lhs_vr->type == VR_RANGE && vr_result.type == VR_RANGE + && !all_const) { if (!POINTER_TYPE_P (TREE_TYPE (lhs))) { |