A new assert, since move below the if C->failing() triggers when running any testing, counts do not match up in Valhalla:

assert(!is_mcall || (call_returns[block->_pre_order] <= (uint) current_offset), "ret_addr_offset() not within emitted code");

Disabled for now (testing passed):

https://github.com/openjdk/valhalla/pull/286/commits/d9487db29a9b9cba209ebc256d06969548b849cf