1 files changed, 108 insertions, 0 deletions
diff --git a/src/sat/aig/fraigClass.c b/src/sat/aig/fraigClass.c
new file mode 100644
index 00000000..b3040e2a
--- /dev/null
+++ b/src/sat/aig/fraigClass.c
@@ -0,0 +1,108 @@
+/**CFile****************************************************************
+
+  FileName    [aigFraig.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [And-Inverter Graph package.]
+
+  Synopsis    []
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - June 20, 2005.]
+
+  Revision    [$Id: aigFraig.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "aig.h"
+#include "stmm.h"
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+static unsigned Aig_ManHashKey( unsigned * pData, int nWords );
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Creates the equivalence classes of patterns.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Vec_t * Aig_ManDeriveClassesFirst( Aig_Man_t * p, Aig_SimInfo_t * pInfo )
+{
+    Vec_Vec_t * vClasses;     // equivalence classes
+    stmm_table * tSim2Node;  // temporary hash table hashing key into the class number
+    Aig_Node_t * pNode;       
+    unsigned uKey;
+    int i, * pSpot, ClassNum;
+    assert( pInfo->Type == 1 );
+    // fill in the hash table
+    tSim2Node = stmm_init_table( stmm_numcmp, stmm_numhash );
+    vClasses = Vec_VecAlloc( 100 );
+    Aig_ManForEachNode( p, pNode, i )
+    {
+        if ( Aig_NodeIsPo(pNode) )
+            continue;
+        uKey = Aig_ManHashKey( Aig_SimInfoForNode(pInfo, pNode), pInfo->nWords );
+        if ( !stmm_find_or_add( tSim2Node, (char *)uKey, (char ***)&pSpot ) ) // does not exist
+            *pSpot = (pNode->Id << 1) | 1; // save the node, and do nothing
+        else if ( (*pSpot) & 1 ) // this is a node
+        {
+            // create the class
+            ClassNum = Vec_VecSize( vClasses );
+            Vec_VecPush( vClasses, ClassNum, (void *)((*pSpot) >> 1) );
+            Vec_VecPush( vClasses, ClassNum, (void *)pNode->Id );
+            // save the class
+            *pSpot = (ClassNum << 1); 
+        }
+        else // this is a class
+        {
+            ClassNum = (*pSpot) >> 1;
+            Vec_VecPush( vClasses, ClassNum, (void *)pNode->Id );
+        }
+    }
+    stmm_free_table( tSim2Node );
+    return vClasses;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Computes the hash key of the simulation info.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+unsigned Aig_ManHashKey( unsigned * pData, int nWords )
+{
+    static int Primes[10] = { 1009, 2207, 3779, 4001, 4877, 5381, 6427, 6829, 7213, 7919 };
+    unsigned uKey;
+    int i;
+    uKey = 0;
+    for ( i = 0; i < nWords; i++ )
+        uKey ^= pData[i] * Primes[i%10];
+    return uKey;
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+