tree-chkp.c (chkp_get_hard_register_var_fake_base_address): Rewritten to avoid…

tree-chkp.c (chkp_get_hard_register_var_fake_base_address): Rewritten to avoid overflow for > 32-bit pointers.

	* tree-chkp.c (chkp_get_hard_register_var_fake_base_address):
	Rewritten to avoid overflow for > 32-bit pointers.

From-SVN: r249398

gcc/ChangeLog

-2017-06-20  Jakub Jelinek  <jakub@redhat.com>
+2017-07-20  Jakub Jelinek  <jakub@redhat.com>
+
+	* tree-chkp.c (chkp_get_hard_register_var_fake_base_address):
+	Rewritten to avoid overflow for > 32-bit pointers.
 
 	PR sanitizer/81125
 	* ubsan.h (ubsan_encode_value): Workaround buggy clang++ parser

gcc/tree-chkp.c

@@ -690,9 +690,8 @@ chkp_erase_completed_bounds (void)
 static tree
 chkp_get_hard_register_var_fake_base_address ()
 {
-  tree base = fold_convert (ptr_type_node, integer_zero_node);
-  unsigned HOST_WIDE_INT offset = 1 << (TYPE_PRECISION (ptr_type_node) - 1);
-  return fold_build_pointer_plus_hwi (base, offset);
+  int prec = TYPE_PRECISION (ptr_type_node);
+  return wide_int_to_tree (ptr_type_node, wi::min_value (prec, SIGNED));
 }
 
 /* If we check bounds for a hard register variable, we cannot