path: root/src/opt/cut/cutPre22.c

/**CFile****************************************************************

  FileName    [cutPre22.c]

  SystemName  [ABC: Logic synthesis and verification system.]

  PackageName [Network and node package.]

  Synopsis    [Precomputes truth tables for the 2x2 macro cell.]

  Author      [Alan Mishchenko]
  
  Affiliation [UC Berkeley]

  Date        [Ver. 1.0. Started - June 20, 2005.]

  Revision    [$Id: cutPre22.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]

***********************************************************************/

#include "cutInt.h"

////////////////////////////////////////////////////////////////////////
///                        DECLARATIONS                              ///
////////////////////////////////////////////////////////////////////////

#define CUT_CELL_MVAR  9

typedef struct Cut_Cell_t_ Cut_Cell_t;
typedef struct Cut_CMan_t_ Cut_CMan_t;

struct Cut_Cell_t_
{
    Cut_Cell_t *       pNext;                        // pointer to the next cell in the table
    Cut_Cell_t *       pNextVar;                     // pointer to the next cell of this support size
    Cut_Cell_t *       pParent;                      // pointer to the cell used to derive this one
    int                nUsed;                        // the number of times the cell is used
    char               Box[4];                       // functions in the boxes
    unsigned           nVars          :  4;          // the number of variables
    unsigned           CrossBar0      :  4;          // the variable set equal
    unsigned           CrossBar1      :  4;          // the variable set equal
    unsigned           CrossBarPhase  :  2;          // the phase of the cross bar (0, 1, or 2)
    unsigned           CanonPhase     : 18;          // the canonical phase
    char               CanonPerm[CUT_CELL_MVAR+3];   // semicanonical permutation
    short              Store[2*CUT_CELL_MVAR];       // minterm counts in the cofactors
    unsigned           uTruth[1<<(CUT_CELL_MVAR-5)]; // the current truth table
};

struct Cut_CMan_t_
{
    // storage for canonical cells
    Extra_MmFixed_t *  pMem;
    st_table *         tTable;
    Cut_Cell_t *       pSameVar[CUT_CELL_MVAR+1];
    // elementary truth tables
    unsigned           uInputs[CUT_CELL_MVAR][1<<(CUT_CELL_MVAR-5)];
    // temporary truth tables
    unsigned           uTemp1[22][1<<(CUT_CELL_MVAR-5)];
    unsigned           uTemp2[22][1<<(CUT_CELL_MVAR-5)];
    unsigned           uTemp3[22][1<<(CUT_CELL_MVAR-5)];
    unsigned           uFinal[1<<(CUT_CELL_MVAR-5)];
    unsigned           puAux[1<<(CUT_CELL_MVAR-5)];
    // statistical variables
    int                nTotal;
    int                nGood;
    int                nVarCounts[CUT_CELL_MVAR+1];
    int                nSymGroups[CUT_CELL_MVAR+1];
    int                nSymGroupsE[CUT_CELL_MVAR+1];
    int                timeCanon;
    int                timeSupp;
    int                timeTable;
    int                nCellFound;
    int                nCellNotFound;
};

// NP-classes of functions of 3 variables (22)
//static char * s_NP3[22] = {
//    " 0\n",                          // 00    const 0            // 0 vars
//    " 1\n",                          // 01    const 1            // 0 vars
//    "1 1\n",                         // 02    a                  // 1 vars
//    "11 1\n",                        // 03    ab                 // 2 vars
//    "11 0\n",                        // 04    (ab)'              // 2 vars
//    "10 1\n01 1\n",                  // 05    a<+>b              // 2 vars
//    "111 1\n",                       // 06 0s abc                // 3 vars
//    "111 0\n",                       // 07    (abc)'             //
//    "11- 1\n1-1 1\n",                // 08 1p a(b+c)             //
//    "11- 0\n1-1 0\n",                // 09    (a(b+c))'          //
//    "111 1\n100 1\n010 1\n001 1\n",  // 10 2s a<+>b<+>c          //
//    "10- 0\n1-0 0\n011 0\n",         // 11 3p a<+>bc             //
//    "101 1\n110 1\n",                // 12 4p a(b<+>c)           //
//    "101 0\n110 0\n",                // 13    (a(b<+>c))'        //
//    "11- 1\n1-1 1\n-11 1\n",         // 14 5s ab+bc+ac           //
//    "111 1\n000 1\n",                // 15 6s abc+a'b'c'         //
//    "111 0\n000 0\n",                // 16    (abc+a'b'c')'      //
//    "11- 1\n-11 1\n0-1 1\n",         // 17 7  ab+bc+a'c          //
//    "011 1\n101 1\n110 1\n",         // 18 8s a'bc+ab'c+abc'     //
//    "011 0\n101 0\n110 0\n",         // 19    (a'bc+ab'c+abc')'  //
//    "100 1\n-11 1\n",                // 20 9p ab'c'+bc           //
//    "100 0\n-11 0\n"                 // 21    (ab'c'+bc)'        //
//};

// NP-classes of functions of 3 variables (22)
static char * s_NP3Names[22] = {
    "   const 0            ",
    "   const 1            ",
    "   a                  ",
    "   ab                 ",
    "   (ab)'              ",
    "   a<+>b              ",
    "0s abc                ",
    "   (abc)'             ",
    "1p a(b+c)             ",
    "   (a(b+c))'          ",
    "2s a<+>b<+>c          ",
    "3p a<+>bc             ",
    "4p a(b<+>c)           ",
    "   (a(b<+>c))'        ",
    "5s ab+bc+ac           ",
    "6s abc+a'b'c'         ",
    "   (abc+a'b'c')'      ",
    "7  ab+bc+a'c          ",
    "8s a'bc+ab'c+abc'     ",
    "   (a'bc+ab'c+abc')'  ",
    "9p ab'c'+bc           ",
    "   (ab'c'+bc)'        "
};

// the number of variables in each function
//static int s_NP3VarNums[22] = { 0, 0, 1, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 };

// NPN classes of functions of exactly 3 inputs (10)
static int s_NPNe3[10] = { 6, 8, 10, 11, 12, 14, 15, 17, 18, 20 };

// NPN classes of functions of exactly 3 inputs that are symmetric (5)
//static int s_NPNe3s[10] = { 6, 10, 14, 15, 18 };

// NPN classes of functions of exactly 3 inputs (4)
//static int s_NPNe3p[10] = { 8, 11, 12, 20 };

static Cut_CMan_t * Cut_CManStart();
static void Cut_CManStop( Cut_CMan_t * p );
static void Cut_CellTruthElem( unsigned * InA, unsigned * InB, unsigned * InC, unsigned * pOut, int nVars, int Type );
static void Cut_CellCanonicize( Cut_CMan_t * p, Cut_Cell_t * pCell );
static int  Cut_CellTableLookup( Cut_CMan_t * p, Cut_Cell_t * pCell );
static void Cut_CellSuppMin( Cut_Cell_t * pCell );
static void Cut_CellCrossBar( Cut_Cell_t * pCell );


static Cut_CMan_t * s_pCMan = NULL;

////////////////////////////////////////////////////////////////////////
///                     FUNCTION DEFINITIONS                         ///
////////////////////////////////////////////////////////////////////////

/**Function*************************************************************

  Synopsis    [Start the precomputation manager.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Cut_CellLoad()
{
    FILE * pFile;
    char * pFileName = "cells22_daomap_iwls.txt";
    char pString[1000];
    Cut_CMan_t * p;
    Cut_Cell_t * pCell;
    int Length; //, i;
    pFile = fopen( pFileName, "r" );
    if ( pFile == NULL )
    {
        printf( "Cannot open file \"%s\".\n", pFileName );
        return;
    }
   // start the manager
    p = Cut_CManStart();
    // load truth tables
    while ( fgets(pString, 1000, pFile) )
    {
        Length = strlen(pString);
        pString[Length--] = 0;
        if ( Length == 0 )
            continue;
        // derive the cell
        pCell = (Cut_Cell_t *)Extra_MmFixedEntryFetch( p->pMem );
        memset( pCell, 0, sizeof(Cut_Cell_t) );
        pCell->nVars = Extra_Base2Log(Length*4);
        pCell->nUsed = 1;
//        Extra_TruthCopy( pCell->uTruth, pTruth, nVars );
        Extra_ReadHexadecimal( pCell->uTruth, pString, pCell->nVars );
        Cut_CellSuppMin( pCell );
/*
        // set the elementary permutation
        for ( i = 0; i < (int)pCell->nVars; i++ )
            pCell->CanonPerm[i] = i;
        // canonicize
        pCell->CanonPhase = Extra_TruthSemiCanonicize( pCell->uTruth, p->puAux, pCell->nVars, pCell->CanonPerm, pCell->Store );
*/
        // add to the table
        p->nTotal++;

//        Extra_PrintHexadecimal( stdout, pCell->uTruth, pCell->nVars ); printf( "\n" );
//        if ( p->nTotal == 500 )
//            break;

        if ( !Cut_CellTableLookup( p, pCell ) ) // new cell
            p->nGood++;
    }
    printf( "Read %d cells from file \"%s\". Added %d cells to the table.\n", p->nTotal, pFileName, p->nGood );
    fclose( pFile );
//    return p;
}

/**Function*************************************************************

  Synopsis    [Precomputes truth tables for the 2x2 macro cell.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Cut_CellPrecompute()
{
    Cut_CMan_t * p;
    Cut_Cell_t * pCell, * pTemp;
    int i1, i2, i3, i, j, k, c, clk = clock(); //, clk2 = clock();

    p = Cut_CManStart();

    // precompute truth tables
    for ( i = 0; i < 22; i++ )
        Cut_CellTruthElem( p->uInputs[0], p->uInputs[1], p->uInputs[2], p->uTemp1[i], 9, i );
    for ( i = 0; i < 22; i++ )
        Cut_CellTruthElem( p->uInputs[3], p->uInputs[4], p->uInputs[5], p->uTemp2[i], 9, i );
    for ( i = 0; i < 22; i++ )
        Cut_CellTruthElem( p->uInputs[6], p->uInputs[7], p->uInputs[8], p->uTemp3[i], 9, i );
/*
        if ( k == 8 && ((i1 == 6 && i2 == 14 && i3 == 20) || (i1 == 20 && i2 == 6 && i3 == 14)) )
        {
            Extra_PrintBinary( stdout, &pCell->CanonPhase, pCell->nVars+1 ); printf( " : " );
            for ( i = 0; i < pCell->nVars; i++ )
                printf( "%d=%d/%d  ", pCell->CanonPerm[i], pCell->Store[2*i], pCell->Store[2*i+1] );
            Extra_PrintHexadecimal( stdout, pCell->uTruth, pCell->nVars );
            printf( "\n" );
        }
*/
/*
    // go through symmetric roots
    for ( k = 0; k < 5; k++ )
    for ( i1 =  0; i1 < 22; i1++ )
    for ( i2 = i1; i2 < 22; i2++ )
    for ( i3 = i2; i3 < 22; i3++ )
    {
        // derive the cell
        pCell = (Cut_Cell_t *)Extra_MmFixedEntryFetch( p->pMem );
        memset( pCell, 0, sizeof(Cut_Cell_t) );
        pCell->nVars  = 9;
        pCell->Box[0] = s_NPNe3s[k];
        pCell->Box[1] = i1;
        pCell->Box[2] = i2;
        pCell->Box[3] = i3;
        // fill in the truth table
        Cut_CellTruthElem( p->uTemp1[i1], p->uTemp2[i2], p->uTemp3[i3], pCell->uTruth, 9, s_NPNe3s[k] );
        // canonicize
        Cut_CellCanonicize( pCell );

        // add to the table
        p->nTotal++;
        if ( Cut_CellTableLookup( p, pCell ) ) // already exists
            Extra_MmFixedEntryRecycle( p->pMem, (char *)pCell );
        else
            p->nGood++;
    }

    // go through partially symmetric roots
    for ( k = 0; k < 4; k++ )
    for ( i1 = 0;  i1 < 22; i1++ )
    for ( i2 = 0;  i2 < 22; i2++ )
    for ( i3 = i2; i3 < 22; i3++ )
    {
        // derive the cell
        pCell = (Cut_Cell_t *)Extra_MmFixedEntryFetch( p->pMem );
        memset( pCell, 0, sizeof(Cut_Cell_t) );
        pCell->nVars  = 9;
        pCell->Box[0] = s_NPNe3p[k];
        pCell->Box[1] = i1;
        pCell->Box[2] = i2;
        pCell->Box[3] = i3;
        // fill in the truth table
        Cut_CellTruthElem( p->uTemp1[i1], p->uTemp2[i2], p->uTemp3[i3], pCell->uTruth, 9, s_NPNe3p[k] );
        // canonicize
        Cut_CellCanonicize( pCell );

        // add to the table
        p->nTotal++;
        if ( Cut_CellTableLookup( p, pCell ) ) // already exists
            Extra_MmFixedEntryRecycle( p->pMem, (char *)pCell );
        else
            p->nGood++;
    }

    // go through non-symmetric functions
    for ( i1 = 0; i1 < 22; i1++ )
    for ( i2 = 0; i2 < 22; i2++ )
    for ( i3 = 0; i3 < 22; i3++ )
    {
        // derive the cell
        pCell = (Cut_Cell_t *)Extra_MmFixedEntryFetch( p->pMem );
        memset( pCell, 0, sizeof(Cut_Cell_t) );
        pCell->nVars  = 9;
        pCell->Box[0] = 17;
        pCell->Box[1] = i1;
        pCell->Box[2] = i2;
        pCell->Box[3] = i3;
        // fill in the truth table
        Cut_CellTruthElem( p->uTemp1[i1], p->uTemp2[i2], p->uTemp3[i3], pCell->uTruth, 9, 17 );
        // canonicize
        Cut_CellCanonicize( pCell );

        // add to the table
        p->nTotal++;
        if ( Cut_CellTableLookup( p, pCell ) ) // already exists
            Extra_MmFixedEntryRecycle( p->pMem, (char *)pCell );
        else
            p->nGood++;
    }
*/

    // go through non-symmetric functions
    for ( k = 0; k < 10; k++ )
    for ( i1 = 0; i1 < 22; i1++ )
    for ( i2 = 0; i2 < 22; i2++ )
    for ( i3 = 0; i3 < 22; i3++ )
    {
        // derive the cell
        pCell = (Cut_Cell_t *)Extra_MmFixedEntryFetch( p->pMem );
        memset( pCell, 0, sizeof(Cut_Cell_t) );
        pCell->nVars  = 9;
        pCell->Box[0] = s_NPNe3[k];
        pCell->Box[1] = i1;
        pCell->Box[2] = i2;
        pCell->Box[3] = i3;
        // set the elementary permutation
        for ( i = 0; i < (int)pCell->nVars; i++ )
            pCell->CanonPerm[i] = i;
        // fill in the truth table
        Cut_CellTruthElem( p->uTemp1[i1], p->uTemp2[i2], p->uTemp3[i3], pCell->uTruth, 9, s_NPNe3[k] );
        // minimize the support
        Cut_CellSuppMin( pCell );

        // canonicize
        pCell->CanonPhase = Extra_TruthSemiCanonicize( pCell->uTruth, p->puAux, pCell->nVars, pCell->CanonPerm, pCell->Store );

        // add to the table
        p->nTotal++;
        if ( Cut_CellTableLookup( p, pCell ) ) // already exists
            Extra_MmFixedEntryRecycle( p->pMem, (char *)pCell );
        else
        {
            p->nGood++;
            p->nVarCounts[pCell->nVars]++;

            if ( pCell->nVars )
            for ( i = 0; i < (int)pCell->nVars-1; i++ )
            {
                if ( pCell->Store[2*i] != pCell->Store[2*(i+1)] ) // i and i+1 cannot be symmetric
                    continue;
                // i and i+1 can be symmetric
                // find the end of this group
                for ( j = i+1; j < (int)pCell->nVars; j++ )
                    if ( pCell->Store[2*i] != pCell->Store[2*j] ) 
                        break;

                if ( pCell->Store[2*i] == pCell->Store[2*i+1] )
                    p->nSymGroupsE[j-i]++;
                else
                    p->nSymGroups[j-i]++;
                i = j - 1;
            }
/*
            if ( pCell->nVars == 3 )
            {
                Extra_PrintBinary( stdout, pCell->uTruth, 32 ); printf( "\n" );
                for ( i = 0; i < (int)pCell->nVars; i++ )
                    printf( "%d=%d/%d  ", pCell->CanonPerm[i], pCell->Store[2*i], pCell->Store[2*i+1] );
                printf( "\n" );
            }
*/
        }
    }

    printf( "BASIC: Total = %d. Good = %d. Entry = %d. ", (int)p->nTotal, (int)p->nGood, (int)sizeof(Cut_Cell_t) );
    PRT( "Time", clock() - clk );
    printf( "Cells:  " );
    for ( i = 0; i <= 9; i++ )
        printf( "%d=%d ", i, p->nVarCounts[i] );
    printf( "\nDiffs:  " );
    for ( i = 0; i <= 9; i++ )
        printf( "%d=%d ", i, p->nSymGroups[i] );
    printf( "\nEquals: " );
    for ( i = 0; i <= 9; i++ )
        printf( "%d=%d ", i, p->nSymGroupsE[i] );
    printf( "\n" );

    // continue adding new cells using support
    for ( k = CUT_CELL_MVAR; k > 3; k-- )
    {
        for ( pTemp = p->pSameVar[k]; pTemp; pTemp = pTemp->pNextVar )
        for ( i1 = 0; i1 < k; i1++ )
        for ( i2 = i1+1; i2 < k; i2++ )
        for ( c = 0; c < 3; c++ )
        {
            // derive the cell
            pCell = (Cut_Cell_t *)Extra_MmFixedEntryFetch( p->pMem );
            memset( pCell, 0, sizeof(Cut_Cell_t) );
            pCell->nVars   = pTemp->nVars;
            pCell->pParent = pTemp;
            // set the elementary permutation
            for ( i = 0; i < (int)pCell->nVars; i++ )
                pCell->CanonPerm[i] = i;
            // fill in the truth table
            Extra_TruthCopy( pCell->uTruth, pTemp->uTruth, pTemp->nVars );
            // create the cross-bar
            pCell->CrossBar0 = i1;
            pCell->CrossBar1 = i2;
            pCell->CrossBarPhase = c;
            Cut_CellCrossBar( pCell );
            // minimize the support
//clk2 = clock();
            Cut_CellSuppMin( pCell );
//p->timeSupp += clock() - clk2;
            // canonicize
//clk2 = clock();
            pCell->CanonPhase = Extra_TruthSemiCanonicize( pCell->uTruth, p->puAux, pCell->nVars, pCell->CanonPerm, pCell->Store );
//p->timeCanon += clock() - clk2;

            // add to the table
//clk2 = clock();
            p->nTotal++;
            if ( Cut_CellTableLookup( p, pCell ) ) // already exists
                Extra_MmFixedEntryRecycle( p->pMem, (char *)pCell );
            else
            {
                p->nGood++;
                p->nVarCounts[pCell->nVars]++;

                for ( i = 0; i < (int)pCell->nVars-1; i++ )
                {
                    if ( pCell->Store[2*i] != pCell->Store[2*(i+1)] ) // i and i+1 cannot be symmetric
                        continue;
                    // i and i+1 can be symmetric
                    // find the end of this group
                    for ( j = i+1; j < (int)pCell->nVars; j++ )
                        if ( pCell->Store[2*i] != pCell->Store[2*j] ) 
                            break;

                    if ( pCell->Store[2*i] == pCell->Store[2*i+1] )
                        p->nSymGroupsE[j-i]++;
                    else
                        p->nSymGroups[j-i]++;
                    i = j - 1;
                }
/*
                if ( pCell->nVars == 3 )
                {
                    Extra_PrintBinary( stdout, pCell->uTruth, 32 ); printf( "\n" );
                    for ( i = 0; i < (int)pCell->nVars; i++ )
                        printf( "%d=%d/%d  ", pCell->CanonPerm[i], pCell->Store[2*i], pCell->Store[2*i+1] );
                    printf( "\n" );
                }
*/
            }
//p->timeTable += clock() - clk2;
        }

        printf( "VAR %d: Total = %d. Good = %d. Entry = %d. ", k, p->nTotal, p->nGood, (int)sizeof(Cut_Cell_t) );
        PRT( "Time", clock() - clk );
        printf( "Cells:  " );
        for ( i = 0; i <= 9; i++ )
            printf( "%d=%d ", i, p->nVarCounts[i] );
        printf( "\nDiffs:  " );
        for ( i = 0; i <= 9; i++ )
            printf( "%d=%d ", i, p->nSymGroups[i] );
        printf( "\nEquals: " );
        for ( i = 0; i <= 9; i++ )
            printf( "%d=%d ", i, p->nSymGroupsE[i] );
        printf( "\n" );
    }
//    printf( "\n" );
    PRT( "Supp ", p->timeSupp );
    PRT( "Canon", p->timeCanon );
    PRT( "Table", p->timeTable );
//    Cut_CManStop( p );
}

/**Function*************************************************************

  Synopsis    [Check the table.]

  Description [Returns 1 if such a truth table already exists.]
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
int Cut_CellTableLookup( Cut_CMan_t * p, Cut_Cell_t * pCell )
{
    Cut_Cell_t ** pSlot, * pTemp;
    unsigned Hash;
    Hash = Extra_TruthHash( pCell->uTruth, Extra_TruthWordNum( pCell->nVars ) );
    if ( !st_find_or_add( p->tTable, (char *)(PORT_PTRUINT_T)Hash, (char ***)&pSlot ) )
        *pSlot = NULL;
    for ( pTemp = *pSlot; pTemp; pTemp = pTemp->pNext )
    {
        if ( pTemp->nVars != pCell->nVars )
            continue;
        if ( Extra_TruthIsEqual(pTemp->uTruth, pCell->uTruth, pCell->nVars) )
            return 1;
    }
    // the entry is new
    pCell->pNext = *pSlot;
    *pSlot = pCell;
    // add it to the variable support list
    pCell->pNextVar = p->pSameVar[pCell->nVars];
    p->pSameVar[pCell->nVars] = pCell;
    return 0;
}

/**Function*************************************************************

  Synopsis    []

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Cut_CellSuppMin( Cut_Cell_t * pCell )
{
    static unsigned uTemp[1<<(CUT_CELL_MVAR-5)];
    unsigned * pIn, * pOut, * pTemp;
    int i, k, Counter, Temp;

    // go backward through the support variables and remove redundant
    for ( k = pCell->nVars - 1; k >= 0; k-- )
        if ( !Extra_TruthVarInSupport(pCell->uTruth, pCell->nVars, k) )
        {
            // shift all the variables above this one
            Counter = 0;
            pIn = pCell->uTruth; pOut = uTemp;
            for ( i = k; i < (int)pCell->nVars - 1; i++ )
            {
                Extra_TruthSwapAdjacentVars( pOut, pIn, pCell->nVars, i );
                pTemp = pIn; pIn = pOut; pOut = pTemp;
                // swap the support vars
                Temp = pCell->CanonPerm[i]; 
                pCell->CanonPerm[i] = pCell->CanonPerm[i+1];
                pCell->CanonPerm[i+1] = Temp;
                Counter++;
            }
            // return the function back into its place
            if ( Counter & 1 )
                Extra_TruthCopy( pOut, pIn, pCell->nVars );
            // remove one variable
            pCell->nVars--;
//            Extra_PrintBinary( stdout, pCell->uTruth, (1<<pCell->nVars) ); printf( "\n" );
        }
}

/**Function*************************************************************

  Synopsis    []

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Cut_CellCrossBar( Cut_Cell_t * pCell )
{
    static unsigned uTemp0[1<<(CUT_CELL_MVAR-5)];
    static unsigned uTemp1[1<<(CUT_CELL_MVAR-5)];
    Extra_TruthCopy( uTemp0, pCell->uTruth, pCell->nVars );
    Extra_TruthCopy( uTemp1, pCell->uTruth, pCell->nVars );
    if ( pCell->CanonPhase == 0 )
    {
        Extra_TruthCofactor0( uTemp0, pCell->nVars, pCell->CrossBar0 );
        Extra_TruthCofactor0( uTemp0, pCell->nVars, pCell->CrossBar1 );
        Extra_TruthCofactor1( uTemp1, pCell->nVars, pCell->CrossBar0 );
        Extra_TruthCofactor1( uTemp1, pCell->nVars, pCell->CrossBar1 );
    }
    else if ( pCell->CanonPhase == 1 )
    {
        Extra_TruthCofactor1( uTemp0, pCell->nVars, pCell->CrossBar0 );
        Extra_TruthCofactor0( uTemp0, pCell->nVars, pCell->CrossBar1 );
        Extra_TruthCofactor0( uTemp1, pCell->nVars, pCell->CrossBar0 );
        Extra_TruthCofactor1( uTemp1, pCell->nVars, pCell->CrossBar1 );
    }
    else if ( pCell->CanonPhase == 2 )
    {
        Extra_TruthCofactor0( uTemp0, pCell->nVars, pCell->CrossBar0 );
        Extra_TruthCofactor1( uTemp0, pCell->nVars, pCell->CrossBar1 );
        Extra_TruthCofactor1( uTemp1, pCell->nVars, pCell->CrossBar0 );
        Extra_TruthCofactor0( uTemp1, pCell->nVars, pCell->CrossBar1 );
    }
    else assert( 0 );
    Extra_TruthMux( pCell->uTruth, uTemp0, uTemp1, pCell->nVars, pCell->CrossBar0 );
}

/**Function*************************************************************

  Synopsis    []

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Cut_CellTruthElem( unsigned * InA, unsigned * InB, unsigned * InC, unsigned * pOut, int nVars, int Type )
{
    int nWords = Extra_TruthWordNum( nVars );
    int i;

    assert( Type < 22 );
    switch ( Type )
    {
    // " 0\n",                         // 00   const 0
    case 0:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = 0;
        return;
    // " 1\n",                         // 01   const 1
    case 1:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = 0xFFFFFFFF;
        return;
    // "1 1\n",                        // 02   a
    case 2:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = InA[i];
        return;
    // "11 1\n",                       // 03   ab
    case 3:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = InA[i] & InB[i];
        return;
    // "11 0\n",                       // 04   (ab)'
    case 4:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = ~(InA[i] & InB[i]);
        return;
    // "10 1\n01 1\n",                 // 05   a<+>b
    case 5:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = InA[i] ^ InB[i];
        return;
    // "111 1\n",                      // 06 + abc
    case 6:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = InA[i] & InB[i] & InC[i];
        return;
    // "111 0\n",                      // 07   (abc)'
    case 7:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = ~(InA[i] & InB[i] & InC[i]);
        return;
    // "11- 1\n1-1 1\n",               // 08 + a(b+c)
    case 8:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = InA[i] & (InB[i] | InC[i]);
        return;
    // "11- 0\n1-1 0\n",               // 09   (a(b+c))'
    case 9:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = ~(InA[i] & (InB[i] | InC[i]));
        return;
    // "111 1\n100 1\n010 1\n001 1\n", // 10 + a<+>b<+>c
    case 10:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = InA[i] ^ InB[i] ^ InC[i];
        return;
    // "10- 0\n1-0 0\n011 0\n",        // 11 + a<+>bc
    case 11:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = InA[i] ^ (InB[i] & InC[i]);
        return;
    // "101 1\n110 1\n",               // 12 + a(b<+>c)
    case 12:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = InA[i] & (InB[i] ^ InC[i]);
        return;
    // "101 0\n110 0\n",               // 13   (a(b<+>c))'
    case 13:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = ~(InA[i] & (InB[i] ^ InC[i]));
        return;
    // "11- 1\n1-1 1\n-11 1\n",        // 14 + ab+bc+ac
    case 14:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = (InA[i] & InB[i]) | (InB[i] & InC[i]) | (InA[i] & InC[i]);
        return;
    // "111 1\n000 1\n",               // 15 + abc+a'b'c'
    case 15:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = (InA[i] & InB[i] & InC[i]) | (~InA[i] & ~InB[i] & ~InC[i]);
        return;
    // "111 0\n000 0\n",               // 16   (abc+a'b'c')'
    case 16:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = ~((InA[i] & InB[i] & InC[i]) | (~InA[i] & ~InB[i] & ~InC[i]));
        return;
    // "11- 1\n-11 1\n0-1 1\n",        // 17 + ab+bc+a'c
    case 17:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = (InA[i] & InB[i]) | (InB[i] & InC[i]) | (~InA[i] & InC[i]);
        return;
    // "011 1\n101 1\n110 1\n",        // 18 + a'bc+ab'c+abc'
    case 18:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = (~InA[i] & InB[i] & InC[i]) | (InA[i] & ~InB[i] & InC[i]) | (InA[i] & InB[i] & ~InC[i]);
        return;
    // "011 0\n101 0\n110 0\n",        // 19   (a'bc+ab'c+abc')'
    case 19:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = ~((~InA[i] & InB[i] & InC[i]) | (InA[i] & ~InB[i] & InC[i]) | (InA[i] & InB[i] & ~InC[i]));
        return;
    // "100 1\n-11 1\n",               // 20 + ab'c'+bc
    case 20:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = (InA[i] & ~InB[i] & ~InC[i]) | (InB[i] & InC[i]);
        return;
    // "100 0\n-11 0\n"                // 21   (ab'c'+bc)'
    case 21:
        for ( i = 0; i < nWords; i++ )
            pOut[i] = ~((InA[i] & ~InB[i] & ~InC[i]) | (InB[i] & InC[i]));
        return;
    }
}


/**Function*************************************************************

  Synopsis    [Start the precomputation manager.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Cut_CMan_t * Cut_CManStart()
{
    Cut_CMan_t * p;
    int i, k;
    // start the manager
    assert( sizeof(unsigned) == 4 );
    p = ALLOC( Cut_CMan_t, 1 );
    memset( p, 0, sizeof(Cut_CMan_t) );
    // start the table and the memory manager
    p->tTable = st_init_table(st_ptrcmp,st_ptrhash);
    p->pMem = Extra_MmFixedStart( sizeof(Cut_Cell_t) );
    // set elementary truth tables
    for ( k = 0; k < CUT_CELL_MVAR; k++ )
        for ( i = 0; i < (1<<CUT_CELL_MVAR); i++ )
            if ( i & (1 << k) )
                p->uInputs[k][i>>5] |= (1 << (i&31));
    s_pCMan = p;
    return p;
}

/**Function*************************************************************

  Synopsis    []

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Cut_CManStop( Cut_CMan_t * p )
{
    st_free_table( p->tTable );
    Extra_MmFixedStop( p->pMem );
    free( p );
}
/**Function*************************************************************

  Synopsis    []

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
int Cut_CellIsRunning()
{
    return s_pCMan != NULL;
}

/**Function*************************************************************

  Synopsis    []

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Cut_CellDumpToFile()
{
    FILE * pFile;
    Cut_CMan_t * p = s_pCMan;
    Cut_Cell_t * pTemp;
    char * pFileName = "celllib22.txt";
    int NumUsed[10][5] = {{0}};
    int BoxUsed[22][5] = {{0}};
    int i, k, Counter;
    int clk = clock();

    if ( p == NULL )
    {
        printf( "Cut_CellDumpToFile: Cell manager is not defined.\n" );
        return;
    }

    // count the number of cells used
    for ( k = CUT_CELL_MVAR; k >= 0; k-- )
    {
        for ( pTemp = p->pSameVar[k]; pTemp; pTemp = pTemp->pNextVar )
        {
            if ( pTemp->nUsed == 0 )
                NumUsed[k][0]++;
            else if ( pTemp->nUsed < 10 )
                NumUsed[k][1]++;
            else if ( pTemp->nUsed < 100 )
                NumUsed[k][2]++;
            else if ( pTemp->nUsed < 1000 )
                NumUsed[k][3]++;
            else 
                NumUsed[k][4]++;

            for ( i = 0; i < 4; i++ )
                if ( pTemp->nUsed == 0 )
                    BoxUsed[ (int)pTemp->Box[i] ][0]++;
                else if ( pTemp->nUsed < 10 )
                    BoxUsed[ (int)pTemp->Box[i] ][1]++;
                else if ( pTemp->nUsed < 100 )
                    BoxUsed[ (int)pTemp->Box[i] ][2]++;
                else if ( pTemp->nUsed < 1000 )
                    BoxUsed[ (int)pTemp->Box[i] ][3]++;
                else 
                    BoxUsed[ (int)pTemp->Box[i] ][4]++;
        }
    }

    printf( "Functions found = %10d.  Functions not found = %10d.\n", p->nCellFound, p->nCellNotFound );
    for ( k = 0; k <= CUT_CELL_MVAR; k++ )
    {
        printf( "%3d  : ", k );
        for ( i = 0; i < 5; i++ ) 
            printf( "%8d ", NumUsed[k][i] );
        printf( "\n" );
    }
    printf( "Box usage:\n" );
    for ( k = 0; k < 22; k++ )
    {
        printf( "%3d  : ", k );
        for ( i = 0; i < 5; i++ ) 
            printf( "%8d ", BoxUsed[k][i] );
        printf( "  %s", s_NP3Names[k] );
        printf( "\n" );
    }

    pFile = fopen( pFileName, "w" );
    if ( pFile == NULL )
    {
        printf( "Cut_CellDumpToFile: Cannout open output file.\n" );
        return;
    }

    Counter = 0;
    for ( k = 0; k <= CUT_CELL_MVAR; k++ )
    {
        for ( pTemp = p->pSameVar[k]; pTemp; pTemp = pTemp->pNextVar )
            if ( pTemp->nUsed > 0 )
            {
                Extra_PrintHexadecimal( pFile, pTemp->uTruth, (k <= 5? 5 : k) );
                fprintf( pFile, "\n" );
                Counter++;
            }
        fprintf( pFile, "\n" );
    }
    fclose( pFile );

    printf( "Library composed of %d functions is written into file \"%s\".  ", Counter, pFileName );

    PRT( "Time", clock() - clk );
}


/**Function*************************************************************

  Synopsis    [Looks up if the given function exists in the hash table.]

  Description [If the function exists, returns 1, meaning that it can be
  implemented using two levels of 3-input LUTs. If the function does not 
  exist, return 0.]
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
int Cut_CellTruthLookup( unsigned * pTruth, int nVars )
{
    Cut_CMan_t * p = s_pCMan;
    Cut_Cell_t * pTemp;
    Cut_Cell_t Cell, * pCell = &Cell;
    unsigned Hash;
    int i;

    // cell manager is not defined
    if ( p == NULL )
    {
        printf( "Cut_CellTruthLookup: Cell manager is not defined.\n" );
        return 0;
    }

    // canonicize
    memset( pCell, 0, sizeof(Cut_Cell_t) );
    pCell->nVars = nVars;
    Extra_TruthCopy( pCell->uTruth, pTruth, nVars );
    Cut_CellSuppMin( pCell );
    // set the elementary permutation
    for ( i = 0; i < (int)pCell->nVars; i++ )
        pCell->CanonPerm[i] = i;
    // canonicize
    pCell->CanonPhase = Extra_TruthSemiCanonicize( pCell->uTruth, p->puAux, pCell->nVars, pCell->CanonPerm, pCell->Store );


    // check if the cell exists
    Hash = Extra_TruthHash( pCell->uTruth, Extra_TruthWordNum(pCell->nVars) );
    if ( st_lookup( p->tTable, (char *)(PORT_PTRUINT_T)Hash, (char **)&pTemp ) )
    {
        for ( ; pTemp; pTemp = pTemp->pNext )
        {
            if ( pTemp->nVars != pCell->nVars )
                continue;
            if ( Extra_TruthIsEqual(pTemp->uTruth, pCell->uTruth, pCell->nVars) )
            {
                pTemp->nUsed++;
                p->nCellFound++;
                return 1;
            }
        }
    }
    p->nCellNotFound++;
    return 0;
}


////////////////////////////////////////////////////////////////////////
///                       END OF FILE                                ///
////////////////////////////////////////////////////////////////////////