1 files changed, 33 insertions, 0 deletions
diff --git a/gcc/tree.c b/gcc/tree.c
index 15171e3..f3889e2 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -6892,6 +6892,39 @@ in_array_bounds_p (tree ref)
   return true;
 }
 
+/* Returns true if it is possible to prove that the range of
+   an array access REF (an ARRAY_RANGE_REF expression) falls
+   into the array bounds.  */
+
+bool
+range_in_array_bounds_p (tree ref)
+{
+  tree domain_type = TYPE_DOMAIN (TREE_TYPE (ref));
+  tree range_min, range_max, min, max;
+
+  range_min = TYPE_MIN_VALUE (domain_type);
+  range_max = TYPE_MAX_VALUE (domain_type);
+  if (!range_min
+      || !range_max
+      || TREE_CODE (range_min) != INTEGER_CST
+      || TREE_CODE (range_max) != INTEGER_CST)
+    return false;
+
+  min = array_ref_low_bound (ref);
+  max = array_ref_up_bound (ref);
+  if (!min
+      || !max
+      || TREE_CODE (min) != INTEGER_CST
+      || TREE_CODE (max) != INTEGER_CST)
+    return false;
+
+  if (tree_int_cst_lt (range_min, min)
+      || tree_int_cst_lt (max, range_max))
+    return false;
+
+  return true;
+}
+
 /* Return true if T (assumed to be a DECL) is a global variable.  */
 
 bool