1 files changed, 98 insertions, 0 deletions
diff --git a/src/intersim/pim.cpp b/src/intersim/pim.cpp
new file mode 100644
index 0000000..be5872c
--- /dev/null
+++ b/src/intersim/pim.cpp
@@ -0,0 +1,98 @@
+#include "booksim.hpp"
+#include <iostream>
+
+#include "pim.hpp"
+#include "random_utils.hpp"
+
+//#define DEBUG_PIM
+
+PIM::PIM( const Configuration &config,
+          Module *parent, const string& name,
+          int inputs, int outputs ) :
+DenseAllocator( config, parent, name, inputs, outputs )
+{
+   _PIM_iter = config.GetInt( "alloc_iters" );
+
+   _grants = new int [_outputs];
+}
+
+PIM::~PIM( )
+{
+   delete [] _grants;
+}
+
+void PIM::Allocate( )
+{
+   int input;
+   int output;
+
+   int input_offset;
+   int output_offset;
+
+   _ClearMatching( );
+
+   for ( int iter = 0; iter < _PIM_iter; ++iter ) {
+      // Grant phase --- outputs randomly choose
+      // between one of their requests
+
+      for ( output = 0; output < _outputs; ++output ) {
+         _grants[output] = -1;
+
+         // A random arbiter between input requests
+         input_offset  = RandomInt( _inputs - 1 );
+
+         for ( int i = 0; i < _inputs; ++i ) {
+            input = ( i + input_offset ) % _inputs;  
+
+            if ( ( _request[input][output].label != -1 ) && 
+                 ( _inmatch[input] == -1 ) &&
+                 ( _outmatch[output] == -1 ) ) {
+
+               // Grant
+               _grants[output] = input;
+               break;
+            }
+         }
+      }
+
+      // Accept phase -- inputs randomly choose
+      // between input_speedup of their grants
+
+      for ( input = 0; input < _inputs; ++input ) {
+
+         // A random arbiter between output grants
+         output_offset  = RandomInt( _outputs - 1 );
+
+         for ( int o = 0; o < _outputs; ++o ) {
+            output = ( o + output_offset ) % _outputs;
+
+            if ( _grants[output] == input ) {
+
+               // Accept
+               _inmatch[input]   = output;
+               _outmatch[output] = input;
+
+               break;
+            }
+         }
+      }
+   }
+
+#ifdef DEBUG_PIM
+   if ( _outputs == 8 ) {
+      cout << "input match: " << endl;
+      for ( int i = 0; i < _inputs; ++i ) {
+         cout << "  from " << i << " to " << _inmatch[i] << endl;
+      }
+      cout << endl;
+   }
+
+   cout << "output match: ";
+   for ( int j = 0; j < _outputs; ++j ) {
+      cout << _outmatch[j] << " ";
+   }
+   cout << endl;
+#endif
+}
+
+