Fixes in aqfp_view and fanout_limit_view (lsils#452)

* sort fanouts of PIs

* tests for fanout_limit_view

* duplicate popular PIs in fanout_limit_view

* Revert "duplicate popular PIs in fanout_limit_view"

This reverts commit b80008a.

include/mockturtle/views/aqfp_view.hpp

@@ -226,6 +226,11 @@ class aqfp_view : public Ntk
  count += num_buffers( n );
  });
  }
+ else
+ {
+ assert( !_ps.balance_pis && "Does not make sense to balance but not branch PIs" );
+ }
+
  this->foreach_gate( [&]( auto const& n ){
  count += num_buffers( n );
  });
@@ -420,6 +425,13 @@ class aqfp_view : public Ntk
  this->foreach_gate( [&]( auto const& n ){
  on_update( n );
  });
+
+ if ( _ps.branch_pis )
+ {
+ this->foreach_pi( [&]( auto const& n ){
+ on_update( n );
+ });
+ }
  }
 
  void on_update( node const& n )

test/views/fanout_limit_view.cpp

@@ -0,0 +1,120 @@
+#include <catch.hpp>
+
+#include <mockturtle/traits.hpp>
+#include <mockturtle/networks/mig.hpp>
+#include <mockturtle/views/fanout_limit_view.hpp>
+
+using namespace mockturtle;
+
+TEST_CASE( "test node replication", "[fanout_limit_view]" )
+{
+ using node = mig_network::node;
+ using signal = mig_network::signal;
+
+ fanout_limit_view_params ps{4u};
+ fanout_limit_view<mig_network> lim_mig{ps};
+
+ signal const a = lim_mig.create_pi();
+ signal const b = lim_mig.create_pi();
+ signal const c = lim_mig.create_pi();
+
+ /* create a node */
+ signal const f1 = lim_mig.create_maj( a, b, c );
+
+ /* make f1 very popular */
+ lim_mig.create_and( f1, a );
+ lim_mig.create_and( f1, b );
+ lim_mig.create_and( f1, c );
+ lim_mig.create_or( f1, a );
+
+ CHECK( lim_mig.num_gates() == 5u );
+
+ lim_mig.create_or( f1, b );
+ lim_mig.create_or( f1, c );
+
+ CHECK( lim_mig.num_gates() == 8u );
+ lim_mig.foreach_gate( [&]( node const& n ){
+ CHECK( lim_mig.fanout_size( n ) <= 4u );
+ });
+}
+
+TEST_CASE( "test rippled replication", "[fanout_limit_view]" )
+{
+ using node = mig_network::node;
+ using signal = mig_network::signal;
+
+ fanout_limit_view_params ps{4u};
+ fanout_limit_view<mig_network> lim_mig{ps};
+
+ signal const a = lim_mig.create_pi();
+ signal const b = lim_mig.create_pi();
+ signal const c = lim_mig.create_pi();
+ signal const d = lim_mig.create_pi();
+ signal const e = lim_mig.create_pi();
+
+ /* create two nodes */
+ signal const f1 = lim_mig.create_maj( a, b, c );
+ signal const f2 = lim_mig.create_maj( d, f1, e );
+
+ /* make f1 and f2 popular */
+ lim_mig.create_and( f1, a );
+ lim_mig.create_and( f1, b );
+ lim_mig.create_and( f1, c );
+
+ lim_mig.create_and( f2, a );
+ lim_mig.create_and( f2, b );
+ lim_mig.create_and( f2, c );
+ lim_mig.create_or( f2, a );
+
+ CHECK( lim_mig.num_gates() == 9u );
+ lim_mig.foreach_gate( [&]( node const& n ){
+ CHECK( lim_mig.fanout_size( n ) <= 4u );
+ });
+
+ /* +3 majority gates, because first f2 has to be replicated, and then also f1 */
+ lim_mig.create_or( f2, b );
+
+ CHECK( lim_mig.num_gates() == 12u );
+ lim_mig.foreach_gate( [&]( node const& n ){
+ CHECK( lim_mig.fanout_size( n ) <= 4u );
+ });
+
+ CHECK( lim_mig.fanout_size( lim_mig.get_node( f1 ) ) == 4u );
+ CHECK( lim_mig.fanout_size( lim_mig.get_node( f2 ) ) == 4u );
+}
+
+TEST_CASE( "test duplicate fanout node", "[fanout_limit_view]" )
+{
+ using node = mig_network::node;
+ using signal = mig_network::signal;
+
+ fanout_limit_view_params ps{4u};
+ fanout_limit_view<mig_network> lim_mig{ps};
+
+ signal const a = lim_mig.create_pi();
+ signal const b = lim_mig.create_pi();
+ signal const c = lim_mig.create_pi();
+
+ signal const f = lim_mig.create_maj( a, b, c );
+
+ /* only one node is needed for fanout up to 4 */
+ lim_mig.create_po( f );
+ lim_mig.create_po( f );
+ lim_mig.create_po( f );
+ lim_mig.create_po( f );
+
+ CHECK( lim_mig.num_gates() == 1u );
+ CHECK( lim_mig.fanout_size( lim_mig.get_node( f ) ) == 4u );
+
+ /* afterward the node need to be replicated */
+ lim_mig.create_po( f );
+ lim_mig.create_po( f );
+ lim_mig.create_po( f );
+ lim_mig.create_po( f );
+
+ CHECK( lim_mig.num_gates() == 2u );
+
+ lim_mig.foreach_gate( [&]( node const& n ){
+ CHECK( lim_mig.fanout_size( n ) <= 4u );
+ });
+}