Experiment with support minimization.

2 files changed, 227 insertions, 0 deletions

diff --git a/src/misc/extra/extraUtilSupp.c b/src/misc/extra/extraUtilSupp.c
new file mode 100644
index 00000000..4699b7ae
--- /dev/null
+++ b/src/misc/extra/extraUtilSupp.c
@@ -0,0 +1,226 @@
+/**CFile****************************************************************
+
+  FileName    [extraUtilSupp.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [extra]
+
+  Synopsis    [Support minimization.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - June 20, 2005.]
+
+  Revision    [$Id: extraUtilSupp.c,v 1.0 2003/02/01 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include "misc/vec/vec.h"
+
+ABC_NAMESPACE_IMPL_START
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Generate m-out-of-n vectors.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int Abc_SuppCountOnes( unsigned i )
+{
+    i = i - ((i >> 1) & 0x55555555);
+    i = (i & 0x33333333) + ((i >> 2) & 0x33333333);
+    i = ((i + (i >> 4)) & 0x0F0F0F0F);
+    return (i*(0x01010101))>>24;
+}
+Vec_Int_t * Abc_SuppGen( int m, int n )
+{
+    Vec_Int_t * vRes = Vec_IntAlloc( 1000 );
+    int i, Size = (1 << n);
+    for ( i = 0; i < Size; i++ )
+        if ( Abc_SuppCountOnes(i) == m )
+            Vec_IntPush( vRes, i );
+    return vRes;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Generate pairs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Int_t * Abc_SuppGenPairs( Vec_Int_t * p, int nBits )
+{
+    Vec_Int_t * vRes = Vec_IntAlloc( 1000 );
+    unsigned * pMap = ABC_CALLOC( unsigned, 1 << Abc_MaxInt(0,nBits-5) ); 
+    int * pLimit = Vec_IntLimit(p);
+    int * pEntry1 = Vec_IntArray(p);
+    int * pEntry2, Value;
+    for ( ; pEntry1 < pLimit; pEntry1++ )
+    for ( pEntry2 = pEntry1 + 1; pEntry2 < pLimit; pEntry2++ )
+    {
+        Value = *pEntry1 ^ *pEntry2;
+        if ( Abc_InfoHasBit(pMap, Value) )
+            continue;
+        Abc_InfoXorBit( pMap, Value );
+        Vec_IntPush( vRes, Value );
+    }
+    ABC_FREE( pMap );
+    return vRes;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Select variable.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_SuppPrintMask( unsigned uMask, int nBits )
+{
+    int i;
+    for ( i = 0; i < nBits; i++ )
+        printf( "%d", (uMask >> i) & 1 );
+    printf( "\n" );
+}
+void Abc_SuppGenProfile( Vec_Int_t * p, int nBits, int * pCounts )
+{
+    int i, k, b, Ent;
+    Vec_IntForEachEntry( p, Ent, i )
+        for ( b = ((Ent >> nBits) & 1), k = 0; k < nBits; k++ )
+            pCounts[k] += ((Ent >> k) & 1) ^ b;
+}
+void Abc_SuppPrintProfile( Vec_Int_t * p, int nBits )
+{
+    int k, Counts[32] = {0};
+    Abc_SuppGenProfile( p, nBits, Counts );
+    for ( k = 0; k < nBits; k++ )
+        printf( "%2d : %6d  %6.2f %%\n", k, Counts[k], 100.0 * Counts[k] / Vec_IntSize(p) );
+}
+int Abc_SuppGenFindBest( Vec_Int_t * p, int nBits, int * pMerit )
+{
+    int k, kBest = 0, Counts[32] = {0};
+    Abc_SuppGenProfile( p, nBits, Counts );
+    for ( k = 1; k < nBits; k++ )
+        if ( Counts[kBest] < Counts[k] )
+            kBest = k;
+    *pMerit = Counts[kBest];
+    return kBest;
+}
+void Abc_SuppGenSelectVar( Vec_Int_t * p, int nBits, int iVar )
+{
+    int * pEntry = Vec_IntArray(p);
+    int * pLimit = Vec_IntLimit(p);
+    for ( ; pEntry < pLimit; pEntry++ )
+        if ( (*pEntry >> iVar) & 1 )
+            *pEntry ^= (1 << nBits);
+}
+void Abc_SuppGenFilter( Vec_Int_t * p, int nBits )
+{
+    int i, k = 0, Ent;
+    Vec_IntForEachEntry( p, Ent, i )
+        if ( ((Ent >> nBits) & 1) == 0 )
+            Vec_IntWriteEntry( p, k++, Ent );
+    Vec_IntShrink( p, k );
+}
+unsigned Abc_SuppFindOne( Vec_Int_t * p, int nBits )
+{
+    unsigned uMask = 0;
+    int Prev = -1, This, Var;
+    while ( 1 )
+    {
+        Var = Abc_SuppGenFindBest( p, nBits, &This );
+        if ( Prev >= This )
+            break;
+        Prev = This;
+        Abc_SuppGenSelectVar( p, nBits, Var );
+        uMask |= (1 << Var);
+    }
+    return uMask;
+}
+int Abc_SuppMinimize( Vec_Int_t * p, int nBits, int fVerbose )
+{
+    unsigned uMask; int i;
+    for ( i = 0; Vec_IntSize(p) > 0; i++ )
+    {
+//        Abc_SuppPrintProfile( p, nBits );
+        uMask = Abc_SuppFindOne( p, nBits );
+        Abc_SuppGenFilter( p, nBits );   
+        if ( !fVerbose )
+            continue;
+        // print stats
+        printf( "%2d : ", i );
+        printf( "%6d  ", Vec_IntSize(p) );
+        Abc_SuppPrintMask( uMask, nBits );
+//        printf( "\n" );
+    }
+    return i;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Create representation.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_SuppTest( int nOnes, int nVars, int fVerbose )
+{
+    int nVarsMin;
+    abctime clk = Abc_Clock();
+    // create the problem
+    Vec_Int_t * vRes = Abc_SuppGen( nOnes, nVars );
+    Vec_Int_t * vPairs = Abc_SuppGenPairs( vRes, nVars );
+    printf( "M = %2d  N = %2d : ", nOnes, nVars );
+    printf( "K = %6d   ",  Vec_IntSize(vRes) );
+    printf( "Total = %10d   ", Vec_IntSize(vRes) * (Vec_IntSize(vRes) - 1) /2 );
+    printf( "Distinct = %8d   ",  Vec_IntSize(vPairs) );
+    Abc_PrintTime( 1, "Reduction time", Abc_Clock() - clk );
+    // solve the problem
+    clk = Abc_Clock();
+    nVarsMin = Abc_SuppMinimize( vPairs, nVars, fVerbose );
+    printf( "Solution with %d variables found.  ", nVarsMin );
+    Abc_PrintTime( 1, "Covering time", Abc_Clock() - clk );
+    Vec_IntFree( vPairs );
+    Vec_IntFree( vRes );
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/misc/extra/module.make b/src/misc/extra/module.make
index 466d2279..1503cec1 100644
--- a/src/misc/extra/module.make
+++ b/src/misc/extra/module.make
@@ -17,5 +17,6 @@ SRC +=    src/misc/extra/extraBddAuto.c \
     src/misc/extra/extraUtilPerm.c \
     src/misc/extra/extraUtilProgress.c \
     src/misc/extra/extraUtilReader.c \
+    src/misc/extra/extraUtilSupp.c \
     src/misc/extra/extraUtilTruth.c \
     src/misc/extra/extraUtilUtil.c