1 files changed, 133 insertions, 0 deletions
diff --git a/src/intersim/fly.cpp b/src/intersim/fly.cpp
new file mode 100644
index 0000000..1793cc2
--- /dev/null
+++ b/src/intersim/fly.cpp
@@ -0,0 +1,133 @@
+#include "booksim.hpp"
+#include <vector>
+#include <sstream>
+
+#include "fly.hpp"
+#include "misc_utils.hpp"
+
+//#define DEBUG_FLY
+
+KNFly::KNFly( const Configuration &config ) :
+Network( config )
+{
+   _ComputeSize( config );
+   _Alloc( );
+   _BuildNet( config );
+}
+
+void KNFly::_ComputeSize( const Configuration &config )
+{
+   _k = config.GetInt( "k" );
+   _n = config.GetInt( "n" );
+
+   gK = _k; gN = _n;
+
+   _sources = powi( _k, _n );
+   _dests   = powi( _k, _n );
+
+   // n stages of k^(n-1) k x k switches
+   _size     = _n*powi( _k, _n-1 );
+
+   // n-1 sets of wiring between the stages
+   _channels = (_n-1)*_sources;
+}
+
+void KNFly::_BuildNet( const Configuration &config )
+{
+   ostringstream router_name;
+
+   int per_stage = powi( _k, _n-1 );
+
+   int node = 0;
+   int c;
+
+   for ( int stage = 0; stage < _n; ++stage ) {
+      for ( int addr = 0; addr < per_stage; ++addr ) {
+
+         router_name << "router_" << stage << "_" << addr;
+         _routers[node] = Router::NewRouter( config, this, router_name.str( ), 
+                                             node, _k, _k );
+         router_name.seekp( 0, ios::beg );
+
+#ifdef DEBUG_FLY
+         cout << "connecting node " << node << " to:" << endl;
+#endif 
+
+         for ( int port = 0; port < _k; ++port ) {
+            // Input connections
+            if ( stage == 0 ) {
+               c = addr*_k + port;
+               _routers[node]->AddInputChannel( &_inject[c], &_inject_cred[c] );
+#ifdef DEBUG_FLY	  
+               cout << "  injection channel " << c << endl;
+#endif 
+            } else {
+               c = _InChannel( stage, addr, port );
+               _routers[node]->AddInputChannel( &_chan[c], &_chan_cred[c] );
+#ifdef DEBUG_FLY
+               cout << "  input channel " << c << endl;
+#endif 
+            }
+
+            // Output connections
+            if ( stage == _n - 1 ) {
+               c = addr*_k + port;
+               _routers[node]->AddOutputChannel( &_eject[c], &_eject_cred[c] );
+#ifdef DEBUG_FLY
+               cout << "  ejection channel " << c << endl;
+#endif 
+            } else {
+               c = _OutChannel( stage, addr, port );
+               _routers[node]->AddOutputChannel( &_chan[c], &_chan_cred[c] );
+#ifdef DEBUG_FLY
+               cout << "  output channel " << c << endl;
+#endif 
+            }
+         }
+
+         ++node;
+      }
+   }
+}
+
+int KNFly::_OutChannel( int stage, int addr, int port ) const
+{
+   return stage*_sources + addr*_k + port;
+}
+
+int KNFly::_InChannel( int stage, int addr, int port ) const
+{
+   int in_addr;
+   int in_port;
+
+   // Channels are between {node,port}
+   //   { d_{n-1} ... d_{n-stage} ... d_0 } and
+   //   { d_{n-1} ... d_0         ... d_{n-stage} }
+
+   int shift = powi( _k, _n-stage-1 );
+
+   int last_digit = port;
+   int zero_digit = ( addr / shift ) % _k;
+
+   // swap zero and last digit to get first node's address
+   in_addr = addr - zero_digit*shift + last_digit*shift;
+   in_port = zero_digit;
+
+   return(stage-1)*_sources + in_addr*_k + in_port;
+}
+
+int KNFly::GetN( ) const
+{
+   return _n;
+}
+
+int KNFly::GetK( ) const
+{
+   return _k;
+}
+
+double KNFly::Capacity( ) const
+{
+   return 1.0;
+}
+