/**CFile****************************************************************
FileName [resFilter.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Resynthesis package.]
Synopsis [Filtering resubstitution candidates.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - January 15, 2007.]
Revision [$Id: resFilter.c,v 1.00 2007/01/15 00:00:00 alanmi Exp $]
***********************************************************************/
#include "base/abc/abc.h"
#include "resInt.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
static unsigned * Res_FilterCollectFaninInfo( Res_Win_t * pWin, Res_Sim_t * pSim, unsigned uMask );
static int Res_FilterCriticalFanin( Abc_Obj_t * pNode );
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Finds sets of feasible candidates.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Res_FilterCandidates( Res_Win_t * pWin, Abc_Ntk_t * pAig, Res_Sim_t * pSim, Vec_Vec_t * vResubs, Vec_Vec_t * vResubsW, int nFaninsMax, int fArea )
{
Abc_Obj_t * pFanin, * pFanin2, * pFaninTemp;
unsigned * pInfo, * pInfoDiv, * pInfoDiv2;
int Counter, RetValue, i, i2, d, d2, iDiv, iDiv2, k;
// check that the info the node is one
pInfo = (unsigned *)Vec_PtrEntry( pSim->vOuts, 1 );
RetValue = Abc_InfoIsOne( pInfo, pSim->nWordsOut );
if ( RetValue == 0 )
{
// printf( "Failed 1!\n" );
return 0;
}
// collect the fanin info
pInfo = Res_FilterCollectFaninInfo( pWin, pSim, ~0 );
RetValue = Abc_InfoIsOne( pInfo, pSim->nWordsOut );
if ( RetValue == 0 )
{
// printf( "Failed 2!\n" );
return 0;
}
// try removing each fanin
// printf( "Fanins: " );
Counter = 0;
Vec_VecClear( vResubs );
Vec_VecClear( vResubsW );
Abc_ObjForEachFanin( pWin->pNode, pFanin, i )
{
if ( fArea && Abc_ObjFanoutNum(pFanin) > 1 )
continue;
// get simulation info without this fanin
pInfo = Res_FilterCollectFaninInfo( pWin, pSim, ~(1 << i) );
RetValue = Abc_InfoIsOne( pInfo, pSim->nWordsOut );
if ( RetValue )
{
// printf( "Node %4d. Candidate fanin %4d.\n", pWin->pNode->Id, pFanin->Id );
// collect the nodes
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,0) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,1) );
Abc_ObjForEachFanin( pWin->pNode, pFaninTemp, k )
{
if ( k != i )
{
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,2+k) );
Vec_VecPush( vResubsW, Counter, pFaninTemp );
}
}
Counter++;
if ( Counter == Vec_VecSize(vResubs) )
return Counter;
}
}
// try replacing each critical fanin by a non-critical fanin
Abc_ObjForEachFanin( pWin->pNode, pFanin, i )
{
if ( Abc_ObjFanoutNum(pFanin) > 1 )
continue;
// get simulation info without this fanin
pInfo = Res_FilterCollectFaninInfo( pWin, pSim, ~(1 << i) );
// go over the set of divisors
for ( d = Abc_ObjFaninNum(pWin->pNode) + 2; d < Abc_NtkPoNum(pAig); d++ )
{
pInfoDiv = (unsigned *)Vec_PtrEntry( pSim->vOuts, d );
iDiv = d - (Abc_ObjFaninNum(pWin->pNode) + 2);
if ( !Abc_InfoIsOrOne( pInfo, pInfoDiv, pSim->nWordsOut ) )
continue;
// collect the nodes
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,0) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,1) );
// collect the remaning fanins and the divisor
Abc_ObjForEachFanin( pWin->pNode, pFaninTemp, k )
{
if ( k != i )
{
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,2+k) );
Vec_VecPush( vResubsW, Counter, pFaninTemp );
}
}
// collect the divisor
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,d) );
Vec_VecPush( vResubsW, Counter, Vec_PtrEntry(pWin->vDivs, iDiv) );
Counter++;
if ( Counter == Vec_VecSize(vResubs) )
return Counter;
}
}
// consider the case when two fanins can be added instead of one
if ( Abc_ObjFaninNum(pWin->pNode) < nFaninsMax )
{
// try to replace each critical fanin by two non-critical fanins
Abc_ObjForEachFanin( pWin->pNode, pFanin, i )
{
if ( Abc_ObjFanoutNum(pFanin) > 1 )
continue;
// get simulation info without this fanin
pInfo = Res_FilterCollectFaninInfo( pWin, pSim, ~(1 << i) );
// go over the set of divisors
for ( d = Abc_ObjFaninNum(pWin->pNode) + 2; d < Abc_NtkPoNum(pAig); d++ )
{
pInfoDiv = (unsigned *)Vec_PtrEntry( pSim->vOuts, d );
iDiv = d - (Abc_ObjFaninNum(pWin->pNode) + 2);
// go through the second divisor
for ( d2 = d + 1; d2 < Abc_NtkPoNum(pAig); d2++ )
{
pInfoDiv2 = (unsigned *)Vec_PtrEntry( pSim->vOuts, d2 );
iDiv2 = d2 - (Abc_ObjFaninNum(pWin->pNode) + 2);
if ( !Abc_InfoIsOrOne3( pInfo, pInfoDiv, pInfoDiv2, pSim->nWordsOut ) )
continue;
// collect the nodes
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,0) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,1) );
// collect the remaning fanins and the divisor
Abc_ObjForEachFanin( pWin->pNode, pFaninTemp, k )
{
if ( k != i )
{
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,2+k) );
Vec_VecPush( vResubsW, Counter, pFaninTemp );
}
}
// collect the divisor
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,d) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,d2) );
Vec_VecPush( vResubsW, Counter, Vec_PtrEntry(pWin->vDivs, iDiv) );
Vec_VecPush( vResubsW, Counter, Vec_PtrEntry(pWin->vDivs, iDiv2) );
Counter++;
if ( Counter == Vec_VecSize(vResubs) )
return Counter;
}
}
}
}
// try to replace two nets by one
if ( !fArea )
{
Abc_ObjForEachFanin( pWin->pNode, pFanin, i )
{
for ( i2 = i + 1; i2 < Abc_ObjFaninNum(pWin->pNode); i2++ )
{
pFanin2 = Abc_ObjFanin(pWin->pNode, i2);
// get simulation info without these fanins
pInfo = Res_FilterCollectFaninInfo( pWin, pSim, (~(1 << i)) & (~(1 << i2)) );
// go over the set of divisors
for ( d = Abc_ObjFaninNum(pWin->pNode) + 2; d < Abc_NtkPoNum(pAig); d++ )
{
pInfoDiv = (unsigned *)Vec_PtrEntry( pSim->vOuts, d );
iDiv = d - (Abc_ObjFaninNum(pWin->pNode) + 2);
if ( !Abc_InfoIsOrOne( pInfo, pInfoDiv, pSim->nWordsOut ) )
continue;
// collect the nodes
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,0) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,1) );
// collect the remaning fanins and the divisor
Abc_ObjForEachFanin( pWin->pNode, pFaninTemp, k )
{
if ( k != i && k != i2 )
{
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,2+k) );
Vec_VecPush( vResubsW, Counter, pFaninTemp );
}
}
// collect the divisor
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,d) );
Vec_VecPush( vResubsW, Counter, Vec_PtrEntry(pWin->vDivs, iDiv) );
Counter++;
if ( Counter == Vec_VecSize(vResubs) )
return Counter;
}
}
}
}
return Counter;
}
/**Function*************************************************************
Synopsis [Finds sets of feasible candidates.]
Description [This procedure is a special case of the above.]
SideEffects []
SeeAlso []
***********************************************************************/
int Res_FilterCandidatesArea( Res_Win_t * pWin, Abc_Ntk_t * pAig, Res_Sim_t * pSim, Vec_Vec_t * vResubs, Vec_Vec_t * vResubsW, int nFaninsMax )
{
Abc_Obj_t * pFanin;
unsigned * pInfo, * pInfoDiv, * pInfoDiv2;
int Counter, RetValue, d, d2, k, iDiv, iDiv2, iBest;
// check that the info the node is one
pInfo = (unsigned *)Vec_PtrEntry( pSim->vOuts, 1 );
RetValue = Abc_InfoIsOne( pInfo, pSim->nWordsOut );
if ( RetValue == 0 )
{
// printf( "Failed 1!\n" );
return 0;
}
// collect the fanin info
pInfo = Res_FilterCollectFaninInfo( pWin, pSim, ~0 );
RetValue = Abc_InfoIsOne( pInfo, pSim->nWordsOut );
if ( RetValue == 0 )
{
// printf( "Failed 2!\n" );
return 0;
}
// try removing fanins
// printf( "Fanins: " );
Counter = 0;
Vec_VecClear( vResubs );
Vec_VecClear( vResubsW );
// get the best fanins
iBest = Res_FilterCriticalFanin( pWin->pNode );
if ( iBest == -1 )
return 0;
// get the info without the critical fanin
pInfo = Res_FilterCollectFaninInfo( pWin, pSim, ~(1 << iBest) );
RetValue = Abc_InfoIsOne( pInfo, pSim->nWordsOut );
if ( RetValue )
{
// printf( "Can be done without one!\n" );
// collect the nodes
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,0) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,1) );
Abc_ObjForEachFanin( pWin->pNode, pFanin, k )
{
if ( k != iBest )
{
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,2+k) );
Vec_VecPush( vResubsW, Counter, pFanin );
}
}
Counter++;
// printf( "*" );
return Counter;
}
// go through the divisors
for ( d = Abc_ObjFaninNum(pWin->pNode) + 2; d < Abc_NtkPoNum(pAig); d++ )
{
pInfoDiv = (unsigned *)Vec_PtrEntry( pSim->vOuts, d );
iDiv = d - (Abc_ObjFaninNum(pWin->pNode) + 2);
if ( !Abc_InfoIsOrOne( pInfo, pInfoDiv, pSim->nWordsOut ) )
continue;
//if ( Abc_ObjLevel(pWin->pNode) <= Abc_ObjLevel( Vec_PtrEntry(pWin->vDivs, iDiv) ) )
// printf( "Node level = %d. Divisor level = %d.\n", Abc_ObjLevel(pWin->pNode), Abc_ObjLevel( Vec_PtrEntry(pWin->vDivs, iDiv) ) );
// collect the nodes
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,0) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,1) );
// collect the remaning fanins and the divisor
Abc_ObjForEachFanin( pWin->pNode, pFanin, k )
{
if ( k != iBest )
{
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,2+k) );
Vec_VecPush( vResubsW, Counter, pFanin );
}
}
// collect the divisor
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,d) );
Vec_VecPush( vResubsW, Counter, Vec_PtrEntry(pWin->vDivs, iDiv) );
Counter++;
if ( Counter == Vec_VecSize(vResubs) )
break;
}
if ( Counter > 0 || Abc_ObjFaninNum(pWin->pNode) >= nFaninsMax )
return Counter;
// try to find the node pairs
for ( d = Abc_ObjFaninNum(pWin->pNode) + 2; d < Abc_NtkPoNum(pAig); d++ )
{
pInfoDiv = (unsigned *)Vec_PtrEntry( pSim->vOuts, d );
iDiv = d - (Abc_ObjFaninNum(pWin->pNode) + 2);
// go through the second divisor
for ( d2 = d + 1; d2 < Abc_NtkPoNum(pAig); d2++ )
{
pInfoDiv2 = (unsigned *)Vec_PtrEntry( pSim->vOuts, d2 );
iDiv2 = d2 - (Abc_ObjFaninNum(pWin->pNode) + 2);
if ( !Abc_InfoIsOrOne3( pInfo, pInfoDiv, pInfoDiv2, pSim->nWordsOut ) )
continue;
// collect the nodes
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,0) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,1) );
// collect the remaning fanins and the divisor
Abc_ObjForEachFanin( pWin->pNode, pFanin, k )
{
if ( k != iBest )
{
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,2+k) );
Vec_VecPush( vResubsW, Counter, pFanin );
}
}
// collect the divisor
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,d) );
Vec_VecPush( vResubs, Counter, Abc_NtkPo(pAig,d2) );
Vec_VecPush( vResubsW, Counter, Vec_PtrEntry(pWin->vDivs, iDiv) );
Vec_VecPush( vResubsW, Counter, Vec_PtrEntry(pWin->vDivs, iDiv2) );
Counter++;
if ( Counter == Vec_VecSize(vResubs) )
break;
}
if ( Counter == Vec_VecSize(vResubs) )
break;
}
return Counter;
}
/**Function*************************************************************
Synopsis [Finds sets of feasible candidates.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
unsigned * Res_FilterCollectFaninInfo( Res_Win_t * pWin, Res_Sim_t * pSim, unsigned uMask )
{
Abc_Obj_t * pFanin;
unsigned * pInfo;
int i;
pInfo = (unsigned *)Vec_PtrEntry( pSim->vOuts, 0 );
Abc_InfoClear( pInfo, pSim->nWordsOut );
Abc_ObjForEachFanin( pWin->pNode, pFanin, i )
{
if ( uMask & (1 << i) )
Abc_InfoOr( pInfo, (unsigned *)Vec_PtrEntry(pSim->vOuts, 2+i), pSim->nWordsOut );
}
return pInfo;
}
/**Function*************************************************************
Synopsis [Returns the index of the most critical fanin.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Res_FilterCriticalFanin( Abc_Obj_t * pNode )
{
Abc_Obj_t * pFanin;
int i, iBest = -1, CostMax = 0, CostCur;
Abc_ObjForEachFanin( pNode, pFanin, i )
{
if ( !Abc_ObjIsNode(pFanin) )
continue;
if ( Abc_ObjFanoutNum(pFanin) > 1 )
continue;
CostCur = Res_WinVisitMffc( pFanin );
if ( CostMax < CostCur )
{
CostMax = CostCur;
iBest = i;
}
}
// if ( CostMax > 0 )
// printf( "<%d>", CostMax );
return iBest;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END