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/**CFile****************************************************************
FileName [sswSweep.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Inductive prover with constraints.]
Synopsis [One round of SAT sweeping.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - September 1, 2008.]
Revision [$Id: sswSweep.c,v 1.00 2008/09/01 00:00:00 alanmi Exp $]
***********************************************************************/
#include "sswInt.h"
#include "bar.h"
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Retrives value of the PI in the original AIG.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Ssw_ManGetSatVarValue( Ssw_Man_t * p, Aig_Obj_t * pObj, int f )
{
int fUseNoBoundary = 0;
Aig_Obj_t * pObjFraig;
int Value;
// assert( Aig_ObjIsPi(pObj) );
pObjFraig = Ssw_ObjFrame( p, pObj, f );
if ( fUseNoBoundary )
{
Value = Ssw_CnfGetNodeValue( p->pMSat, Aig_Regular(pObjFraig) );
Value ^= Aig_IsComplement(pObjFraig);
}
else
{
int nVarNum = Ssw_ObjSatNum( p->pMSat, Aig_Regular(pObjFraig) );
Value = (!nVarNum)? 0 : (Aig_IsComplement(pObjFraig) ^ sat_solver_var_value( p->pMSat->pSat, nVarNum ));
}
// Value = (Aig_IsComplement(pObjFraig) ^ ((!nVarNum)? 0 : sat_solver_var_value( p->pSat, nVarNum )));
// Value = (!nVarNum)? Aig_ManRandom(0) & 1 : (Aig_IsComplement(pObjFraig) ^ sat_solver_var_value( p->pSat, nVarNum ));
if ( p->pPars->fPolarFlip )
{
if ( Aig_Regular(pObjFraig)->fPhase ) Value ^= 1;
}
return Value;
}
/**Function*************************************************************
Synopsis [Performs fraiging for the internal nodes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Ssw_CheckConstraints( Ssw_Man_t * p )
{
Aig_Obj_t * pObj, * pObj2;
int nConstrPairs, i;
int Counter = 0;
nConstrPairs = Aig_ManPoNum(p->pFrames)-Aig_ManRegNum(p->pAig);
assert( (nConstrPairs & 1) == 0 );
for ( i = 0; i < nConstrPairs; i += 2 )
{
pObj = Aig_ManPo( p->pFrames, i );
pObj2 = Aig_ManPo( p->pFrames, i+1 );
if ( Ssw_NodesAreEquiv( p, Aig_ObjFanin0(pObj), Aig_ObjFanin0(pObj2) ) != 1 )
{
Ssw_NodesAreConstrained( p, Aig_ObjChild0(pObj), Aig_ObjChild0(pObj2) );
Counter++;
}
}
printf( "Total constraints = %d. Added constraints = %d.\n", nConstrPairs/2, Counter );
}
/**Function*************************************************************
Synopsis [Copy pattern from the solver into the internal storage.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Ssw_SmlSavePatternAigPhase( Ssw_Man_t * p, int f )
{
Aig_Obj_t * pObj;
int i;
memset( p->pPatWords, 0, sizeof(unsigned) * p->nPatWords );
Aig_ManForEachPi( p->pAig, pObj, i )
if ( Aig_ObjPhaseReal( Ssw_ObjFrame(p, pObj, f) ) )
Aig_InfoSetBit( p->pPatWords, i );
}
/**Function*************************************************************
Synopsis [Copy pattern from the solver into the internal storage.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Ssw_SmlSavePatternAig( Ssw_Man_t * p, int f )
{
Aig_Obj_t * pObj;
int i;
memset( p->pPatWords, 0, sizeof(unsigned) * p->nPatWords );
Aig_ManForEachPi( p->pAig, pObj, i )
if ( Ssw_ManGetSatVarValue( p, pObj, f ) )
Aig_InfoSetBit( p->pPatWords, i );
}
/**Function*************************************************************
Synopsis [Saves one counter-example into internal storage.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Ssw_SmlAddPatternDyn( Ssw_Man_t * p )
{
Aig_Obj_t * pObj;
unsigned * pInfo;
int i, nVarNum;
// iterate through the PIs of the frames
Vec_PtrForEachEntry( p->pMSat->vUsedPis, pObj, i )
{
assert( Aig_ObjIsPi(pObj) );
nVarNum = Ssw_ObjSatNum( p->pMSat, pObj );
assert( nVarNum > 0 );
if ( sat_solver_var_value( p->pMSat->pSat, nVarNum ) )
{
pInfo = Vec_PtrEntry( p->vSimInfo, Aig_ObjPioNum(pObj) );
Aig_InfoSetBit( pInfo, p->nPatterns );
}
}
}
/**Function*************************************************************
Synopsis [Performs fraiging for one node.]
Description [Returns the fraiged node.]
SideEffects []
SeeAlso []
***********************************************************************/
int Ssw_ManSweepNode( Ssw_Man_t * p, Aig_Obj_t * pObj, int f, int fBmc )
{
Aig_Obj_t * pObjRepr, * pObjFraig, * pObjFraig2, * pObjReprFraig;
int RetValue, clk;
// get representative of this class
pObjRepr = Aig_ObjRepr( p->pAig, pObj );
if ( pObjRepr == NULL )
return 0;
// get the fraiged node
pObjFraig = Ssw_ObjFrame( p, pObj, f );
// get the fraiged representative
pObjReprFraig = Ssw_ObjFrame( p, pObjRepr, f );
// check if constant 0 pattern distinquishes these nodes
assert( pObjFraig != NULL && pObjReprFraig != NULL );
assert( (pObj->fPhase == pObjRepr->fPhase) == (Aig_ObjPhaseReal(pObjFraig) == Aig_ObjPhaseReal(pObjReprFraig)) );
// if the fraiged nodes are the same, return
if ( Aig_Regular(pObjFraig) == Aig_Regular(pObjReprFraig) )
return 0;
// add constraints on demand
if ( !fBmc && p->pPars->fDynamic )
{
clk = clock();
Ssw_ManLoadSolver( p, pObjRepr, pObj );
p->nRecycleCalls++;
p->timeMarkCones += clock() - clk;
}
// call equivalence checking
if ( Aig_Regular(pObjFraig) != Aig_ManConst1(p->pFrames) )
RetValue = Ssw_NodesAreEquiv( p, Aig_Regular(pObjReprFraig), Aig_Regular(pObjFraig) );
else
RetValue = Ssw_NodesAreEquiv( p, Aig_Regular(pObjFraig), Aig_Regular(pObjReprFraig) );
if ( RetValue == 1 ) // proved equivalent
{
pObjFraig2 = Aig_NotCond( pObjReprFraig, pObj->fPhase ^ pObjRepr->fPhase );
Ssw_ObjSetFrame( p, pObj, f, pObjFraig2 );
return 0;
}
if ( RetValue == -1 ) // timed out
{
Ssw_ClassesRemoveNode( p->ppClasses, pObj );
return 1;
}
// disproved the equivalence
if ( !fBmc && p->pPars->fDynamic )
{
Ssw_SmlAddPatternDyn( p );
p->nPatterns++;
return 1;
}
else
Ssw_SmlSavePatternAig( p, f );
// consider uniqueness
if ( !fBmc && !p->pPars->fDynamic && p->pPars->fUniqueness && p->pPars->nFramesK > 1 &&
Ssw_ManUniqueOne( p, pObjRepr, pObj, p->pPars->fVerbose ) && p->iOutputLit == -1 )
{
if ( Ssw_ManUniqueAddConstraint( p, p->vCommon, 0, 1 ) )
{
int RetValue2 = Ssw_NodesAreEquiv( p, Aig_Regular(pObjReprFraig), Aig_Regular(pObjFraig) );
p->iOutputLit = -1;
p->nUniques++;
p->nUniquesAdded++;
if ( RetValue2 == 0 )
{
int x;
// printf( "Second time:\n" );
x = Ssw_ManUniqueOne( p, pObjRepr, pObj, p->pPars->fVerbose );
Ssw_SmlSavePatternAig( p, f );
Ssw_ManResimulateWord( p, pObj, pObjRepr, f );
if ( Aig_ObjRepr( p->pAig, pObj ) == pObjRepr )
printf( "Ssw_ManSweepNode(): Refinement did not happen!!!.\n" );
return 1;
}
else
p->nUniquesUseful++;
// printf( "Counter-example prevented!!!\n" );
return 0;
}
}
if ( p->pPars->nConstrs == 0 )
Ssw_ManResimulateWord( p, pObj, pObjRepr, f );
else
Ssw_ManResimulateBit( p, pObj, pObjRepr );
assert( Aig_ObjRepr( p->pAig, pObj ) != pObjRepr );
if ( Aig_ObjRepr( p->pAig, pObj ) == pObjRepr )
{
printf( "Ssw_ManSweepNode(): Failed to refine representative.\n" );
}
return 1;
}
/**Function*************************************************************
Synopsis [Performs fraiging for the internal nodes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Ssw_ManSweepBmc( Ssw_Man_t * p )
{
Bar_Progress_t * pProgress = NULL;
Aig_Obj_t * pObj, * pObjNew, * pObjLi, * pObjLo;
int i, f, clk;
clk = clock();
// start initialized timeframes
p->pFrames = Aig_ManStart( Aig_ManObjNumMax(p->pAig) * p->pPars->nFramesK );
Saig_ManForEachLo( p->pAig, pObj, i )
Ssw_ObjSetFrame( p, pObj, 0, Aig_ManConst0(p->pFrames) );
// sweep internal nodes
p->fRefined = 0;
if ( p->pPars->fVerbose )
pProgress = Bar_ProgressStart( stdout, Aig_ManObjNumMax(p->pAig) * p->pPars->nFramesK );
// Ssw_ManStartSolver( p );
for ( f = 0; f < p->pPars->nFramesK; f++ )
{
// map constants and PIs
Ssw_ObjSetFrame( p, Aig_ManConst1(p->pAig), f, Aig_ManConst1(p->pFrames) );
Saig_ManForEachPi( p->pAig, pObj, i )
Ssw_ObjSetFrame( p, pObj, f, Aig_ObjCreatePi(p->pFrames) );
// sweep internal nodes
Aig_ManForEachNode( p->pAig, pObj, i )
{
if ( p->pPars->fVerbose )
Bar_ProgressUpdate( pProgress, Aig_ManObjNumMax(p->pAig) * f + i, NULL );
pObjNew = Aig_And( p->pFrames, Ssw_ObjChild0Fra(p, pObj, f), Ssw_ObjChild1Fra(p, pObj, f) );
Ssw_ObjSetFrame( p, pObj, f, pObjNew );
p->fRefined |= Ssw_ManSweepNode( p, pObj, f, 1 );
}
// quit if this is the last timeframe
if ( f == p->pPars->nFramesK - 1 )
break;
// transfer latch input to the latch outputs
// build logic cones for register outputs
Saig_ManForEachLiLo( p->pAig, pObjLi, pObjLo, i )
{
pObjNew = Ssw_ObjChild0Fra(p, pObjLi,f);
Ssw_ObjSetFrame( p, pObjLo, f+1, pObjNew );
Ssw_CnfNodeAddToSolver( p->pMSat, Aig_Regular(pObjNew) );//
}
}
if ( p->pPars->fVerbose )
Bar_ProgressStop( pProgress );
// cleanup
// Ssw_ClassesCheck( p->ppClasses );
p->timeBmc += clock() - clk;
return p->fRefined;
}
/**Function*************************************************************
Synopsis [Performs fraiging for the internal nodes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Ssw_ManSweep( Ssw_Man_t * p )
{
Bar_Progress_t * pProgress = NULL;
Aig_Obj_t * pObj, * pObj2, * pObjNew;
int nConstrPairs, clk, i, f, v;
// perform speculative reduction
clk = clock();
// create timeframes
p->pFrames = Ssw_FramesWithClasses( p );
// add constants
nConstrPairs = Aig_ManPoNum(p->pFrames)-Aig_ManRegNum(p->pAig);
assert( (nConstrPairs & 1) == 0 );
for ( i = 0; i < nConstrPairs; i += 2 )
{
pObj = Aig_ManPo( p->pFrames, i );
pObj2 = Aig_ManPo( p->pFrames, i+1 );
Ssw_NodesAreConstrained( p, Aig_ObjChild0(pObj), Aig_ObjChild0(pObj2) );
}
// build logic cones for register inputs
for ( i = 0; i < Aig_ManRegNum(p->pAig); i++ )
{
pObj = Aig_ManPo( p->pFrames, nConstrPairs + i );
Ssw_CnfNodeAddToSolver( p->pMSat, Aig_ObjFanin0(pObj) );//
}
sat_solver_simplify( p->pMSat->pSat );
// map constants and PIs of the last frame
f = p->pPars->nFramesK;
Ssw_ObjSetFrame( p, Aig_ManConst1(p->pAig), f, Aig_ManConst1(p->pFrames) );
Saig_ManForEachPi( p->pAig, pObj, i )
Ssw_ObjSetFrame( p, pObj, f, Aig_ObjCreatePi(p->pFrames) );
p->timeReduce += clock() - clk;
// bring up the previous frames
if ( p->pPars->fUniqueness )
for ( v = 0; v < f; v++ )
Saig_ManForEachLo( p->pAig, pObj, i )
Ssw_CnfNodeAddToSolver( p->pMSat, Aig_Regular(Ssw_ObjFrame(p, pObj, v)) );
// sweep internal nodes
p->fRefined = 0;
Ssw_ClassesClearRefined( p->ppClasses );
if ( p->pPars->fVerbose )
pProgress = Bar_ProgressStart( stdout, Aig_ManObjNumMax(p->pAig) );
Aig_ManForEachObj( p->pAig, pObj, i )
{
if ( p->pPars->fVerbose )
Bar_ProgressUpdate( pProgress, i, NULL );
if ( Saig_ObjIsLo(p->pAig, pObj) )
p->fRefined |= Ssw_ManSweepNode( p, pObj, f, 0 );
else if ( Aig_ObjIsNode(pObj) )
{
pObjNew = Aig_And( p->pFrames, Ssw_ObjChild0Fra(p, pObj, f), Ssw_ObjChild1Fra(p, pObj, f) );
Ssw_ObjSetFrame( p, pObj, f, pObjNew );
p->fRefined |= Ssw_ManSweepNode( p, pObj, f, 0 );
}
}
if ( p->pPars->fVerbose )
Bar_ProgressStop( pProgress );
// cleanup
// Ssw_ClassesCheck( p->ppClasses );
return p->fRefined;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
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