abcBridge-0.14: abc-build/src/misc/extra/extraUtilThresh.c
/**CFile****************************************************************
FileName [extraUtilThresh.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [extra]
Synopsis [Dealing with threshold functions.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - October 7, 2014.]
Revision [$Id: extraUtilThresh.c,v 1.0 2014/10/07 00:00:00 alanmi Exp $]
***********************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "misc/vec/vec.h"
#include "misc/util/utilTruth.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Checks thresholdness of the function.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Extra_ThreshPrintChow( int Chow0, int * pChow, int nVars )
{
int i;
for ( i = 0; i < nVars; i++ )
printf( "%d ", pChow[i] );
printf( " %d\n", Chow0 );
}
int Extra_ThreshComputeChow( word * t, int nVars, int * pChow )
{
int i, k, Chow0 = 0, nMints = (1 << nVars);
memset( pChow, 0, sizeof(int) * nVars );
// compute Chow coefs
for ( i = 0; i < nMints; i++ )
if ( Abc_TtGetBit(t, i) )
for ( Chow0++, k = 0; k < nVars; k++ )
if ( (i >> k) & 1 )
pChow[k]++;
// compute modified Chow coefs
for ( k = 0; k < nVars; k++ )
pChow[k] = 2 * pChow[k] - Chow0;
return Chow0 - (1 << (nVars-1));
}
void Extra_ThreshSortByChow( word * t, int nVars, int * pChow )
{
int i, nWords = Abc_TtWordNum(nVars);
while ( 1 )
{
int fChange = 0;
for ( i = 0; i < nVars - 1; i++ )
{
if ( pChow[i] >= pChow[i+1] )
continue;
ABC_SWAP( int, pChow[i], pChow[i+1] );
Abc_TtSwapAdjacent( t, nWords, i );
fChange = 1;
}
if ( !fChange )
return;
}
}
static inline int Extra_ThreshWeightedSum( int * pW, int nVars, int m )
{
int i, Cost = 0;
for ( i = 0; i < nVars; i++ )
if ( (m >> i) & 1 )
Cost += pW[i];
return Cost;
}
int Extra_ThreshSelectWeights3( word * t, int nVars, int * pW )
{
int m, Lmin, Lmax, nMints = (1 << nVars);
assert( nVars == 3 );
for ( pW[2] = 1; pW[2] <= nVars; pW[2]++ )
for ( pW[1] = pW[2]; pW[1] <= nVars; pW[1]++ )
for ( pW[0] = pW[1]; pW[0] <= nVars; pW[0]++ )
{
Lmin = 10000; Lmax = 0;
for ( m = 0; m < nMints; m++ )
{
if ( Abc_TtGetBit(t, m) )
Lmin = Abc_MinInt( Lmin, Extra_ThreshWeightedSum(pW, nVars, m) );
else
Lmax = Abc_MaxInt( Lmax, Extra_ThreshWeightedSum(pW, nVars, m) );
if ( Lmax >= Lmin )
break;
// printf( "%c%d ", Abc_TtGetBit(t, m) ? '+' : '-', Extra_ThreshWeightedSum(pW, nVars, m) );
}
// printf( " -%d +%d\n", Lmax, Lmin );
if ( m < nMints )
continue;
assert( Lmax < Lmin );
return Lmin;
}
return 0;
}
int Extra_ThreshSelectWeights4( word * t, int nVars, int * pW )
{
int m, Lmin, Lmax, nMints = (1 << nVars);
assert( nVars == 4 );
for ( pW[3] = 1; pW[3] <= nVars; pW[3]++ )
for ( pW[2] = pW[3]; pW[2] <= nVars; pW[2]++ )
for ( pW[1] = pW[2]; pW[1] <= nVars; pW[1]++ )
for ( pW[0] = pW[1]; pW[0] <= nVars; pW[0]++ )
{
Lmin = 10000; Lmax = 0;
for ( m = 0; m < nMints; m++ )
{
if ( Abc_TtGetBit(t, m) )
Lmin = Abc_MinInt( Lmin, Extra_ThreshWeightedSum(pW, nVars, m) );
else
Lmax = Abc_MaxInt( Lmax, Extra_ThreshWeightedSum(pW, nVars, m) );
if ( Lmax >= Lmin )
break;
}
if ( m < nMints )
continue;
assert( Lmax < Lmin );
return Lmin;
}
return 0;
}
int Extra_ThreshSelectWeights5( word * t, int nVars, int * pW )
{
int m, Lmin, Lmax, nMints = (1 << nVars), Limit = nVars + 0;
assert( nVars == 5 );
for ( pW[4] = 1; pW[4] <= Limit; pW[4]++ )
for ( pW[3] = pW[4]; pW[3] <= Limit; pW[3]++ )
for ( pW[2] = pW[3]; pW[2] <= Limit; pW[2]++ )
for ( pW[1] = pW[2]; pW[1] <= Limit; pW[1]++ )
for ( pW[0] = pW[1]; pW[0] <= Limit; pW[0]++ )
{
Lmin = 10000; Lmax = 0;
for ( m = 0; m < nMints; m++ )
{
if ( Abc_TtGetBit(t, m) )
Lmin = Abc_MinInt( Lmin, Extra_ThreshWeightedSum(pW, nVars, m) );
else
Lmax = Abc_MaxInt( Lmax, Extra_ThreshWeightedSum(pW, nVars, m) );
if ( Lmax >= Lmin )
break;
}
if ( m < nMints )
continue;
assert( Lmax < Lmin );
return Lmin;
}
return 0;
}
int Extra_ThreshSelectWeights6( word * t, int nVars, int * pW )
{
int m, Lmin, Lmax, nMints = (1 << nVars), Limit = nVars + 3;
assert( nVars == 6 );
for ( pW[5] = 1; pW[5] <= Limit; pW[5]++ )
for ( pW[4] = pW[5]; pW[4] <= Limit; pW[4]++ )
for ( pW[3] = pW[4]; pW[3] <= Limit; pW[3]++ )
for ( pW[2] = pW[3]; pW[2] <= Limit; pW[2]++ )
for ( pW[1] = pW[2]; pW[1] <= Limit; pW[1]++ )
for ( pW[0] = pW[1]; pW[0] <= Limit; pW[0]++ )
{
Lmin = 10000; Lmax = 0;
for ( m = 0; m < nMints; m++ )
{
if ( Abc_TtGetBit(t, m) )
Lmin = Abc_MinInt( Lmin, Extra_ThreshWeightedSum(pW, nVars, m) );
else
Lmax = Abc_MaxInt( Lmax, Extra_ThreshWeightedSum(pW, nVars, m) );
if ( Lmax >= Lmin )
break;
}
if ( m < nMints )
continue;
assert( Lmax < Lmin );
return Lmin;
}
return 0;
}
int Extra_ThreshSelectWeights7( word * t, int nVars, int * pW )
{
int m, Lmin, Lmax, nMints = (1 << nVars), Limit = nVars + 6;
assert( nVars == 7 );
for ( pW[6] = 1; pW[6] <= Limit; pW[6]++ )
for ( pW[5] = pW[6]; pW[5] <= Limit; pW[5]++ )
for ( pW[4] = pW[5]; pW[4] <= Limit; pW[4]++ )
for ( pW[3] = pW[4]; pW[3] <= Limit; pW[3]++ )
for ( pW[2] = pW[3]; pW[2] <= Limit; pW[2]++ )
for ( pW[1] = pW[2]; pW[1] <= Limit; pW[1]++ )
for ( pW[0] = pW[1]; pW[0] <= Limit; pW[0]++ )
{
Lmin = 10000; Lmax = 0;
for ( m = 0; m < nMints; m++ )
{
if ( Abc_TtGetBit(t, m) )
Lmin = Abc_MinInt( Lmin, Extra_ThreshWeightedSum(pW, nVars, m) );
else
Lmax = Abc_MaxInt( Lmax, Extra_ThreshWeightedSum(pW, nVars, m) );
if ( Lmax >= Lmin )
break;
}
if ( m < nMints )
continue;
assert( Lmax < Lmin );
return Lmin;
}
return 0;
}
int Extra_ThreshSelectWeights8( word * t, int nVars, int * pW )
{
int m, Lmin, Lmax, nMints = (1 << nVars), Limit = nVars + 1; // <<-- incomplete detection to save runtime!
assert( nVars == 8 );
for ( pW[7] = 1; pW[7] <= Limit; pW[7]++ )
for ( pW[6] = pW[7]; pW[6] <= Limit; pW[6]++ )
for ( pW[5] = pW[6]; pW[5] <= Limit; pW[5]++ )
for ( pW[4] = pW[5]; pW[4] <= Limit; pW[4]++ )
for ( pW[3] = pW[4]; pW[3] <= Limit; pW[3]++ )
for ( pW[2] = pW[3]; pW[2] <= Limit; pW[2]++ )
for ( pW[1] = pW[2]; pW[1] <= Limit; pW[1]++ )
for ( pW[0] = pW[1]; pW[0] <= Limit; pW[0]++ )
{
Lmin = 10000; Lmax = 0;
for ( m = 0; m < nMints; m++ )
{
if ( Abc_TtGetBit(t, m) )
Lmin = Abc_MinInt( Lmin, Extra_ThreshWeightedSum(pW, nVars, m) );
else
Lmax = Abc_MaxInt( Lmax, Extra_ThreshWeightedSum(pW, nVars, m) );
if ( Lmax >= Lmin )
break;
}
if ( m < nMints )
continue;
assert( Lmax < Lmin );
return Lmin;
}
return 0;
}
int Extra_ThreshSelectWeights( word * t, int nVars, int * pW )
{
if ( nVars <= 2 )
return (t[0] & 0xF) != 6 && (t[0] & 0xF) != 9;
if ( nVars == 3 )
return Extra_ThreshSelectWeights3( t, nVars, pW );
if ( nVars == 4 )
return Extra_ThreshSelectWeights4( t, nVars, pW );
if ( nVars == 5 )
return Extra_ThreshSelectWeights5( t, nVars, pW );
if ( nVars == 6 )
return Extra_ThreshSelectWeights6( t, nVars, pW );
if ( nVars == 7 )
return Extra_ThreshSelectWeights7( t, nVars, pW );
if ( nVars == 8 )
return Extra_ThreshSelectWeights8( t, nVars, pW );
return 0;
}
int Extra_ThreshCheck( word * t, int nVars, int * pW )
{
int Chow0, Chow[16];
if ( !Abc_TtIsUnate(t, nVars) )
return 0;
Abc_TtMakePosUnate( t, nVars );
Chow0 = Extra_ThreshComputeChow( t, nVars, Chow );
Extra_ThreshSortByChow( t, nVars, Chow );
return Extra_ThreshSelectWeights( t, nVars, pW );
}
/**Function*************************************************************
Synopsis [Checks unateness of a function.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Extra_ThreshCheckTest()
{
int nVars = 5;
int T, Chow0, Chow[16], Weights[16];
// word t = s_Truths6[0] & s_Truths6[1] & s_Truths6[2] & s_Truths6[3] & s_Truths6[4];
// word t = (s_Truths6[0] & s_Truths6[1]) | (s_Truths6[0] & s_Truths6[2] & s_Truths6[3]) | (s_Truths6[0] & s_Truths6[2] & s_Truths6[4]);
word t = (s_Truths6[2] & s_Truths6[1]) | (s_Truths6[2] & s_Truths6[0] & s_Truths6[3]) | (s_Truths6[2] & s_Truths6[0] & ~s_Truths6[4]);
// word t = (s_Truths6[0] & s_Truths6[1]) | (s_Truths6[0] & s_Truths6[2] & s_Truths6[3]) | (s_Truths6[0] & s_Truths6[2] & s_Truths6[4]) | (s_Truths6[1] & s_Truths6[2] & s_Truths6[3]);
// word t = (s_Truths6[0] & s_Truths6[1]) | (s_Truths6[0] & s_Truths6[2]) | (s_Truths6[0] & s_Truths6[3] & s_Truths6[4] & s_Truths6[5]) |
// (s_Truths6[1] & s_Truths6[2] & s_Truths6[3]) | (s_Truths6[1] & s_Truths6[2] & s_Truths6[4]) | (s_Truths6[1] & s_Truths6[2] & s_Truths6[5]);
int i;
assert( nVars <= 8 );
for ( i = 0; i < nVars; i++ )
printf( "%d %d %d\n", i, Abc_TtPosVar(&t, nVars, i), Abc_TtNegVar(&t, nVars, i) );
// word t = s_Truths6[0] & s_Truths6[1] & s_Truths6[2];
Chow0 = Extra_ThreshComputeChow( &t, nVars, Chow );
if ( (T = Extra_ThreshCheck(&t, nVars, Weights)) )
Extra_ThreshPrintChow( T, Weights, nVars );
else
printf( "No threshold\n" );
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END