/**Function*************************************************************
Synopsis [Creates fast simulation manager.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Saig_SimObj_t * Saig_ManCreateMan( Aig_Man_t * p )
{
Saig_SimObj_t * pAig, * pEntry;
Aig_Obj_t * pObj;
int i;
pAig = ABC_CALLOC( Saig_SimObj_t, Aig_ManObjNumMax(p)+1 );
// printf( "Allocating %7.2f Mb.\n", 1.0 * sizeof(Saig_SimObj_t) * (Aig_ManObjNumMax(p)+1)/(1<<20) );
Aig_ManForEachObj( p, pObj, i )
{
pEntry = pAig + i;
pEntry->Type = pObj->Type;
if ( Aig_ObjIsPi(pObj) || i == 0 )
{
if ( Saig_ObjIsLo(p, pObj) )
{
pEntry->iFan0 = (Saig_ObjLoToLi(p, pObj)->Id << 1);
pEntry->iFan1 = -1;
}
continue;
}
pEntry->iFan0 = (Aig_ObjFaninId0(pObj) << 1) | Aig_ObjFaninC0(pObj);
if ( Aig_ObjIsPo(pObj) )
continue;
assert( Aig_ObjIsNode(pObj) );
pEntry->iFan1 = (Aig_ObjFaninId1(pObj) << 1) | Aig_ObjFaninC1(pObj);
}
/**Function*************************************************************
Synopsis [Performs induction by unrolling timeframes backward.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Saig_ManInduction( Aig_Man_t * p, int nFramesMax, int nConfMax, int fUnique, int fUniqueAll, int fGetCex, int fVerbose, int fVeryVerbose )
{
sat_solver * pSat;
Aig_Man_t * pAigPart;
Cnf_Dat_t * pCnfPart;
Vec_Int_t * vTopVarNums, * vState, * vTopVarIds = NULL;
Vec_Ptr_t * vTop, * vBot;
Aig_Obj_t * pObjPi, * pObjPiCopy, * pObjPo;
int i, k, f, clk, Lits[2], status, RetValue, nSatVarNum, nConfPrev;
int nOldSize, iReg, iLast, fAdded, nConstrs = 0, nClauses = 0;
assert( fUnique == 0 || fUniqueAll == 0 );
assert( Saig_ManPoNum(p) == 1 );
Aig_ManSetPioNumbers( p );
// start the top by including the PO
vBot = Vec_PtrAlloc( 100 );
vTop = Vec_PtrAlloc( 100 );
vState = Vec_IntAlloc( 1000 );
Vec_PtrPush( vTop, Aig_ManPo(p, 0) );
// start the array of CNF variables
vTopVarNums = Vec_IntAlloc( 100 );
// start the solver
pSat = sat_solver_new();
sat_solver_setnvars( pSat, 1000 );
// iterate backward unrolling
RetValue = -1;
nSatVarNum = 0;
if ( fVerbose )
printf( "Induction parameters: FramesMax = %5d. ConflictMax = %6d.\n", nFramesMax, nConfMax );
for ( f = 0; ; f++ )
{
if ( f > 0 )
{
Aig_ManStop( pAigPart );
Cnf_DataFree( pCnfPart );
}
clk = clock();
// get the bottom
Aig_SupportNodes( p, (Aig_Obj_t **)Vec_PtrArray(vTop), Vec_PtrSize(vTop), vBot );
// derive AIG for the part between top and bottom
pAigPart = Aig_ManDupSimpleDfsPart( p, vBot, vTop );
// convert it into CNF
pCnfPart = Cnf_Derive( pAigPart, Aig_ManPoNum(pAigPart) );
Cnf_DataLift( pCnfPart, nSatVarNum );
nSatVarNum += pCnfPart->nVars;
nClauses += pCnfPart->nClauses;
// remember top frame var IDs
if ( fGetCex && vTopVarIds == NULL )
{
vTopVarIds = Vec_IntStartFull( Aig_ManPiNum(p) );
Aig_ManForEachPi( p, pObjPi, i )
{
if ( pObjPi->pData == NULL )
continue;
pObjPiCopy = (Aig_Obj_t *)pObjPi->pData;
assert( Aig_ObjIsPi(pObjPiCopy) );
if ( Saig_ObjIsPi(p, pObjPi) )
Vec_IntWriteEntry( vTopVarIds, Aig_ObjPioNum(pObjPi) + Saig_ManRegNum(p), pCnfPart->pVarNums[Aig_ObjId(pObjPiCopy)] );
else if ( Saig_ObjIsLo(p, pObjPi) )
Vec_IntWriteEntry( vTopVarIds, Aig_ObjPioNum(pObjPi) - Saig_ManPiNum(p), pCnfPart->pVarNums[Aig_ObjId(pObjPiCopy)] );
else assert( 0 );
}
}
// stitch variables of top and bot
assert( Aig_ManPoNum(pAigPart)-1 == Vec_IntSize(vTopVarNums) );
Aig_ManForEachPo( pAigPart, pObjPo, i )
{
if ( i == 0 )
{
// do not perform inductive strengthening
// if ( f > 0 )
// continue;
// add topmost literal
Lits[0] = toLitCond( pCnfPart->pVarNums[pObjPo->Id], f>0 );
if ( !sat_solver_addclause( pSat, Lits, Lits+1 ) )
assert( 0 );
nClauses++;
continue;
}
Lits[0] = toLitCond( Vec_IntEntry(vTopVarNums, i-1), 0 );
Lits[1] = toLitCond( pCnfPart->pVarNums[pObjPo->Id], 1 );
if ( !sat_solver_addclause( pSat, Lits, Lits+2 ) )
assert( 0 );
Lits[0] = toLitCond( Vec_IntEntry(vTopVarNums, i-1), 1 );
Lits[1] = toLitCond( pCnfPart->pVarNums[pObjPo->Id], 0 );
if ( !sat_solver_addclause( pSat, Lits, Lits+2 ) )
assert( 0 );
nClauses += 2;
}
// add CNF to the SAT solver
for ( i = 0; i < pCnfPart->nClauses; i++ )
if ( !sat_solver_addclause( pSat, pCnfPart->pClauses[i], pCnfPart->pClauses[i+1] ) )
break;
if ( i < pCnfPart->nClauses )
{
// printf( "SAT solver became UNSAT after adding clauses.\n" );
RetValue = 1;
break;
}
// create new set of POs to derive new top
Vec_PtrClear( vTop );
Vec_PtrPush( vTop, Aig_ManPo(p, 0) );
Vec_IntClear( vTopVarNums );
nOldSize = Vec_IntSize(vState);
Vec_IntFillExtra( vState, nOldSize + Aig_ManRegNum(p), -1 );
Vec_PtrForEachEntry( Aig_Obj_t *, vBot, pObjPi, i )
{
assert( Aig_ObjIsPi(pObjPi) );
if ( Saig_ObjIsLo(p, pObjPi) )
{
pObjPiCopy = (Aig_Obj_t *)pObjPi->pData;
assert( pObjPiCopy != NULL );
Vec_PtrPush( vTop, Saig_ObjLoToLi(p, pObjPi) );
Vec_IntPush( vTopVarNums, pCnfPart->pVarNums[pObjPiCopy->Id] );
iReg = pObjPi->PioNum - Saig_ManPiNum(p);
assert( iReg >= 0 && iReg < Aig_ManRegNum(p) );
Vec_IntWriteEntry( vState, nOldSize+iReg, pCnfPart->pVarNums[pObjPiCopy->Id] );
}
}
/**Function*************************************************************
Synopsis [Detects constraints using structural methods.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Saig_ManDetectConstr( Aig_Man_t * p, int iOut, Vec_Ptr_t ** pvOuts, Vec_Ptr_t ** pvCons )
{
Vec_Ptr_t * vSuper, * vSuper2 = NULL, * vUnique;
Aig_Obj_t * pObj, * pObj2, * pFlop;
int i, nFlops, RetValue;
assert( iOut >= 0 && iOut < Saig_ManPoNum(p) );
*pvOuts = NULL;
*pvCons = NULL;
pObj = Aig_ObjChild0( Aig_ManCo(p, iOut) );
if ( Aig_IsComplement(pObj) || !Aig_ObjIsNode(pObj) )
{
printf( "The output is not an AND.\n" );
return 0;
}
vSuper = Saig_DetectConstrCollectSuper( pObj );
assert( Vec_PtrSize(vSuper) >= 2 );
nFlops = 0;
Vec_PtrForEachEntry( Aig_Obj_t *, vSuper, pObj, i )
nFlops += Saig_ObjIsLo( p, Aig_Regular(pObj) );
if ( nFlops == 0 )
{
printf( "There is no flop outputs.\n" );
Vec_PtrFree( vSuper );
return 0;
}
// try flops
vUnique = NULL;
Vec_PtrForEachEntry( Aig_Obj_t *, vSuper, pObj, i )
{
pFlop = Aig_Regular( pObj );
if ( !Saig_ObjIsLo(p, pFlop) )
continue;
pFlop = Saig_ObjLoToLi( p, pFlop );
pObj2 = Aig_ObjChild0( pFlop );
if ( !Aig_IsComplement(pObj2) || !Aig_ObjIsNode(Aig_Regular(pObj2)) )
continue;
vSuper2 = Saig_DetectConstrCollectSuper( Aig_Regular(pObj2) );
// every node in vSuper2 should appear in vSuper
vUnique = Saig_ManDetectConstrCheckCont( vSuper, vSuper2 );
if ( vUnique != NULL )
{
/// assert( !Aig_IsComplement(pObj) );
// assert( Vec_PtrFind( vSuper2, pObj ) >= 0 );
if ( Aig_IsComplement(pObj) )
{
printf( "Special flop input is complemented.\n" );
Vec_PtrFreeP( &vUnique );
Vec_PtrFree( vSuper2 );
break;
}
if ( Vec_PtrFind( vSuper2, pObj ) == -1 )
{
printf( "Cannot find special flop about the inputs of OR gate.\n" );
Vec_PtrFreeP( &vUnique );
Vec_PtrFree( vSuper2 );
break;
}
// remove the flop output
Vec_PtrRemove( vSuper2, pObj );
break;
}
Vec_PtrFree( vSuper2 );
}
