PR c++/36695

[pf3gnuchains/gcc-fork.git] / gcc / tree-vrp.c

diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index 1289c49..4b6caca 100644 (file)
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -2557,11 +2557,11 @@ extract_range_from_binary_expr (value_range_t *vr,
          ior_max.high = vr0_max.high | vr1_max.high;
          if (ior_max.high != 0)
            {
-             ior_max.low = ~0u;
+             ior_max.low = ~(unsigned HOST_WIDE_INT)0u;
              ior_max.high |= ((HOST_WIDE_INT) 1
                               << floor_log2 (ior_max.high)) - 1;
            }
-         else
+         else if (ior_max.low != 0)
            ior_max.low |= ((unsigned HOST_WIDE_INT) 1u
                            << floor_log2 (ior_max.low)) - 1;
 
@@ -6361,9 +6361,12 @@ vrp_visit_phi_node (gimple phi)
             minimums.  */
          if (cmp_min > 0 || cmp_min < 0)
            {
-             /* If we will end up with a (-INF, +INF) range, set it
-                to VARYING.  */
-             if (vrp_val_is_max (vr_result.max))
+             /* If we will end up with a (-INF, +INF) range, set it to
+                VARYING.  Same if the previous max value was invalid for
+                the type and we'd end up with vr_result.min > vr_result.max.  */
+             if (vrp_val_is_max (vr_result.max)
+                 || compare_values (TYPE_MIN_VALUE (TREE_TYPE (vr_result.min)),
+                                    vr_result.max) > 0)
                goto varying;
 
              if (!needs_overflow_infinity (TREE_TYPE (vr_result.min))
@@ -6380,9 +6383,12 @@ vrp_visit_phi_node (gimple phi)
             the previous one, go all the way to +INF.  */
          if (cmp_max < 0 || cmp_max > 0)
            {
-             /* If we will end up with a (-INF, +INF) range, set it
-                to VARYING.  */
-             if (vrp_val_is_min (vr_result.min))
+             /* If we will end up with a (-INF, +INF) range, set it to
+                VARYING.  Same if the previous min value was invalid for
+                the type and we'd end up with vr_result.max < vr_result.min.  */
+             if (vrp_val_is_min (vr_result.min)
+                 || compare_values (TYPE_MAX_VALUE (TREE_TYPE (vr_result.max)),
+                                    vr_result.min) < 0)
                goto varying;
 
              if (!needs_overflow_infinity (TREE_TYPE (vr_result.max))
@@ -6512,6 +6518,12 @@ simplify_truth_ops_using_ranges (gimple_stmt_iterator *gsi, gimple stmt)
     !useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (stmt)),
                                TREE_TYPE (op0));
 
+  /* Make sure to not sign-extend -1 as a boolean value.  */
+  if (need_conversion
+      && !TYPE_UNSIGNED (TREE_TYPE (op0))
+      && TYPE_PRECISION (TREE_TYPE (op0)) == 1)
+    return false;
+
   switch (rhs_code)
     {
     case TRUTH_AND_EXPR: