 number of objects allocated on the chaining automatic
differentiation stack. There is a function call for each of these objects in
the reverse pass</li>
<li><code>no_chain_stack</code>, The number of objects allocated on the non-chaining
automatic differentiation stack</li>
<li><code>autodiff_calls</code>, The total number of times the <code>profile</code> statement was
executed with automatic differentiation</li>
<li><code>no_autodiff_calls</code> - The total number of times the <code>profile</code> state