gimple-fold.c (get_range_strlen): Only set *nonstr when an unterminated string is discovered.

	* gimple-fold.c (get_range_strlen): Only set *nonstr when
	an unterminated string is discovered.  Bubble up range
	even for unterminated strings.
	(gimple_fold_builtin_strlen): Do not fold if get_range_strlen
	indicates the string was not terminated via NONSTR.

From-SVN: r264816

gcc/ChangeLog

-2018-10-3  Aldy Hernandez  <aldyh@redhat.com>
+2018-10-02  Jeff Law  <law@redhat.com>
+
+	* gimple-fold.c (get_range_strlen): Only set *nonstr when
+	an unterminated string is discovered.  Bubble up range
+	even for unterminated strings.
+	(gimple_fold_builtin_strlen): Do not fold if get_range_strlen
+	indicates the string was not terminated via NONSTR.
+
+2018-10-03  Aldy Hernandez  <aldyh@redhat.com>
 
 	* tree-vrp.c (extract_range_from_unary_expr): Special case all
 	pointer conversions.

gcc/gimple-fold.c

@@ -1344,8 +1344,13 @@ get_range_strlen (tree arg, tree length[2], bitmap *visited, int type,
 
 	  /* If we potentially had a non-terminated string, then
 	     bubble that information up to the caller.  */
-	  if (!val)
+	  if (!val && data.decl)
+	    {
 	      *nonstr = data.decl;
+	      *minlen = data.len;
+	      *maxlen = data.len;
+	      return type == 0 ? false : true;
+	    }
 	}
 
       if (!val && fuzzy)
@@ -3596,6 +3601,7 @@ gimple_fold_builtin_strlen (gimple_stmt_iterator *gsi)
   tree nonstr;
   tree lenrange[2];
   if (!get_range_strlen (arg, lenrange, 1, true, &nonstr)
+      && !nonstr
       && lenrange[0] && TREE_CODE (lenrange[0]) == INTEGER_CST
       && lenrange[1] && TREE_CODE (lenrange[1]) == INTEGER_CST)
     {