Cut rewriting
-------------

**Header:** ``mockturtle/algorithms/cut_rewriting.hpp``

The following example shows how to rewrite an MIG using precomputed optimum
networks.  In this case the maximum number of variables for a node function is
4.

.. code-block:: c++

   /* derive some MIG */
   mig_network mig = ...;

   /* node resynthesis */
   mig_npn_resynthesis resyn;
   cut_rewriting_params ps;
   ps.cut_enumeration_ps.cut_size = 4;
   mig = cut_rewriting( mig, resyn, ps );
   mig = cleanup_dangling( mig );

It is possible to change the cost function of nodes in cut rewriting.  Here is
an example, in which the cost function only accounts for AND gates in a network,
which corresponds to the multiplicative complexity of a function.

.. code-block:: c++

   template<class Ntk>
   struct mc_cost
   {
     uint32_t operator()( Ntk const& ntk, node<Ntk> const& n ) const
     {
       return ntk.is_and( n ) ? 1 : 0;
     }
   };

   SomeResynthesisClass resyn;
   ntk = cut_rewriting<SomeResynthesisClass, mc_cost>( ntk, resyn );

Parameters and statistics
~~~~~~~~~~~~~~~~~~~~~~~~~

.. doxygenstruct:: mockturtle::cut_rewriting_params
   :members:

.. doxygenstruct:: mockturtle::cut_rewriting_stats
   :members:

Algorithm
~~~~~~~~~

.. doxygenfunction:: mockturtle::cut_rewriting
.. doxygenfunction:: mockturtle::cut_rewriting_with_compatibility_graph

Rewriting functions
~~~~~~~~~~~~~~~~~~~

One can use resynthesis functions that can be passed to `node_resynthesis`, see
:ref:`node_resynthesis_functions`.