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/**CFile****************************************************************
FileName [bmcBmcAnd.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [SAT-based bounded model checking.]
Synopsis [Memory-efficient BMC engine]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: bmcBmcAnd.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "bmc.h"
#include "aig/gia/giaAig.h"
#include "sat/bsat/satStore.h"
#include "sat/cnf/cnf.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
typedef struct Bmc_Mna_t_ Bmc_Mna_t;
struct Bmc_Mna_t_
{
Gia_Man_t * pFrames; // time frames
Vec_Int_t * vId2Var; // maps GIA IDs into SAT vars
Vec_Int_t * vInputs; // inputs of the cone
Vec_Int_t * vOutputs; // outputs of the cone
Vec_Int_t * vNodes; // internal nodes of the cone
sat_solver * pSat; // SAT solver
int nSatVars; // the counter of SAT variables
abctime clkStart; // starting time
};
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [BMC manager manipulation.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Bmc_Mna_t * Bmc_MnaAlloc()
{
Bmc_Mna_t * p;
p = ABC_CALLOC( Bmc_Mna_t, 1 );
p->vId2Var = Vec_IntAlloc( 0 );
p->vInputs = Vec_IntAlloc( 1000 );
p->vOutputs = Vec_IntAlloc( 1000 );
p->vNodes = Vec_IntAlloc( 10000 );
p->pSat = sat_solver_new();
p->nSatVars = 1;
p->clkStart = Abc_Clock();
return p;
}
void Bmc_MnaFree( Bmc_Mna_t * p )
{
Vec_IntFreeP( &p->vId2Var );
Vec_IntFreeP( &p->vInputs );
Vec_IntFreeP( &p->vOutputs );
Vec_IntFreeP( &p->vNodes );
sat_solver_delete( p->pSat );
ABC_FREE( p );
}
/**Function*************************************************************
Synopsis [Derives GIA for the given cone.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Gia_Man_t * Gia_ManBmcDupCone( Gia_Man_t * p, Vec_Int_t * vIns, Vec_Int_t * vNodes, Vec_Int_t * vOuts )
{
Gia_Man_t * pNew;
Vec_Int_t * vTempIn, * vTempNode;
Gia_Obj_t * pObj;
int i;
// save values
vTempIn = Vec_IntAlloc( Vec_IntSize(vIns) );
Gia_ManForEachObjVec( vIns, p, pObj, i )
Vec_IntPush( vTempIn, pObj->Value );
// save values
vTempNode = Vec_IntAlloc( Vec_IntSize(vNodes) );
Gia_ManForEachObjVec( vNodes, p, pObj, i )
Vec_IntPush( vTempNode, pObj->Value );
// derive new GIA
pNew = Gia_ManDupFromVecs( p, vIns, vNodes, vOuts, 0 );
// reset values
Gia_ManForEachObjVec( vIns, p, pObj, i )
pObj->Value = Vec_IntEntry( vTempIn, i );
// reset values
Gia_ManForEachObjVec( vNodes, p, pObj, i )
pObj->Value = Vec_IntEntry( vTempNode, i );
// reset values
Gia_ManForEachObjVec( vOuts, p, pObj, i )
pObj->Value = 0;
Vec_IntFree( vTempIn );
Vec_IntFree( vTempNode );
return pNew;
}
/**Function*************************************************************
Synopsis [Derives GIA for the given cone.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Gia_ManBmcAssignVarIds( Bmc_Mna_t * p, Vec_Int_t * vIns, Vec_Int_t * vUsed, Vec_Int_t * vOuts )
{
int i, iObj, VarC0 = p->nSatVars++;
Vec_IntForEachEntry( vIns, iObj, i )
if ( Vec_IntEntry( p->vId2Var, iObj ) == 0 )
Vec_IntWriteEntry( p->vId2Var, iObj, p->nSatVars++ );
Vec_IntForEachEntryReverse( vUsed, iObj, i )
{
assert( Vec_IntEntry( p->vId2Var, iObj ) == 0 );
Vec_IntWriteEntry( p->vId2Var, iObj, p->nSatVars++ );
}
Vec_IntForEachEntry( vOuts, iObj, i )
{
assert( Vec_IntEntry( p->vId2Var, iObj ) == 0 );
Vec_IntWriteEntry( p->vId2Var, iObj, p->nSatVars++ );
}
// extend the SAT solver
if ( p->nSatVars > sat_solver_nvars(p->pSat) )
sat_solver_setnvars( p->pSat, p->nSatVars );
return VarC0;
}
/**Function*************************************************************
Synopsis [Derives CNF for the given cone.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Gia_ManBmcAddCnf( Bmc_Mna_t * p, Gia_Man_t * pGia, Vec_Int_t * vIns, Vec_Int_t * vNodes, Vec_Int_t * vOuts )
{
Gia_Man_t * pNew = Gia_ManBmcDupCone( pGia, vIns, vNodes, vOuts );
Aig_Man_t * pAig = Gia_ManToAigSimple( pNew );
Cnf_Dat_t * pCnf = Cnf_Derive( pAig, Aig_ManCoNum(pAig) );
Vec_Int_t * vUsed, * vMap;
Gia_Obj_t * pObj;
int i, iObj, VarC0;
// collect used variables
vUsed = Vec_IntAlloc( pCnf->nVars - Vec_IntSize(vIns) - Vec_IntSize(vOuts) );
Gia_ManForEachAnd( pNew, pObj, i )
if ( pCnf->pVarNums[i] >= 0 )
Vec_IntPush( vUsed, Vec_IntEntry(vNodes, i - Vec_IntSize(vIns) - 1) );
// assign variable IDs
VarC0 = Gia_ManBmcAssignVarIds( p, vIns, vUsed, vOuts );
Vec_IntFree( vUsed );
// create variable map from CNF vars into SAT vars
vMap = Vec_IntStartFull( pCnf->nVars );
assert( pCnf->pVarNums[0] > 0 );
Vec_IntWriteEntry( vMap, pCnf->pVarNums[0], VarC0 );
Gia_ManForEachObj1( pNew, pObj, i )
{
if ( pCnf->pVarNums[i] < 0 )
continue;
assert( pCnf->pVarNums[i] >= 0 && pCnf->pVarNums[i] < pCnf->nVars );
if ( Gia_ObjIsCi(pObj) )
iObj = Vec_IntEntry( vIns, i - 1 );
else if ( Gia_ObjIsAnd(pObj) )
iObj = Vec_IntEntry( vNodes, i - Vec_IntSize(vIns) - 1 );
else if ( Gia_ObjIsCo(pObj) )
iObj = Vec_IntEntry( vOuts, i - Vec_IntSize(vIns) - Vec_IntSize(vNodes) - 1 );
else assert( 0 );
assert( Vec_IntEntry(p->vId2Var, iObj) > 0 );
Vec_IntWriteEntry( vMap, pCnf->pVarNums[i], Vec_IntEntry(p->vId2Var, iObj) );
}
//Vec_IntPrint( vMap );
// remap CNF
for ( i = 0; i < pCnf->nLiterals; i++ )
{
assert( pCnf->pClauses[0][i] > 1 && pCnf->pClauses[0][i] < 2 * pCnf->nVars );
pCnf->pClauses[0][i] = Abc_Lit2LitV( Vec_IntArray(vMap), pCnf->pClauses[0][i] );
}
Vec_IntFree( vMap );
// add clauses
for ( i = 0; i < pCnf->nClauses; i++ )
{
/*
int v;
for ( v = 0; v < pCnf->pClauses[i+1] - pCnf->pClauses[i]; v++ )
printf( "%d ", pCnf->pClauses[i][v] );
printf( "\n" );
*/
if ( !sat_solver_addclause( p->pSat, pCnf->pClauses[i], pCnf->pClauses[i+1] ) )
break;
}
if ( i < pCnf->nClauses )
printf( "SAT solver became UNSAT after adding clauses.\n" );
Aig_ManStop( pAig );
Cnf_DataFree( pCnf );
Gia_ManStop( pNew );
}
/**Function*************************************************************
Synopsis [Collects new nodes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Gia_ManBmcAddCone_rec( Bmc_Mna_t * p, Gia_Obj_t * pObj )
{
int iObj;
if ( pObj->fMark0 )
return;
pObj->fMark0 = 1;
iObj = Gia_ObjId( p->pFrames, pObj );
if ( Gia_ObjIsAnd(pObj) && Vec_IntEntry(p->vId2Var, iObj) == 0 )
{
Gia_ManBmcAddCone_rec( p, Gia_ObjFanin0(pObj) );
Gia_ManBmcAddCone_rec( p, Gia_ObjFanin1(pObj) );
Vec_IntPush( p->vNodes, iObj );
}
else
Vec_IntPush( p->vInputs, iObj );
}
void Gia_ManBmcAddCone( Bmc_Mna_t * p, int iStart )
{
Gia_Obj_t * pObj;
int i;
Vec_IntClear( p->vNodes );
Vec_IntClear( p->vInputs );
Vec_IntClear( p->vOutputs );
Vec_IntFillExtra( p->vId2Var, Gia_ManObjNum(p->pFrames), 0 );
for ( i = iStart; i < Gia_ManPoNum(p->pFrames); i++ )
{
pObj = Gia_ManPo(p->pFrames, i);
if ( Gia_ObjChild0(pObj) == Gia_ManConst0(p->pFrames) )
continue;
Gia_ManBmcAddCone_rec( p, Gia_ObjFanin0(pObj) );
Vec_IntPush( p->vOutputs, Gia_ObjId(p->pFrames, pObj) );
}
// clean attributes and create new variables
Gia_ManForEachObjVec( p->vNodes, p->pFrames, pObj, i )
pObj->fMark0 = 0;
Gia_ManForEachObjVec( p->vInputs, p->pFrames, pObj, i )
pObj->fMark0 = 0;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Gia_ManBmcCheckOutputs( Gia_Man_t * pFrames, int iStart )
{
int i;
for ( i = iStart; i < Gia_ManPoNum(pFrames); i++ )
if ( Gia_ObjChild0(Gia_ManPo(pFrames, i)) != Gia_ManConst0(pFrames) )
return 0;
return 1;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Gia_ManBmcPerform( Gia_Man_t * pGia, Bmc_AndPar_t * pPars )
{
Unr_Man_t * pUnroll;
Bmc_Mna_t * p = Bmc_MnaAlloc();
int nFramesMax = pPars->nFramesMax ? pPars->nFramesMax : ABC_INFINITY;
int f, i=0, Lit, status, RetValue = -2;
pUnroll = Unr_ManUnrollStart( pGia, pPars->fVeryVerbose );
for ( f = 0; f < nFramesMax; f++ )
{
p->pFrames = Unr_ManUnrollFrame( pUnroll, f );
if ( !Gia_ManBmcCheckOutputs( p->pFrames, f * Gia_ManPoNum(pGia) ) )
{
// create another slice
Gia_ManBmcAddCone( p, f * Gia_ManPoNum(pGia) );
// create CNF in the SAT solver
Gia_ManBmcAddCnf( p, p->pFrames, p->vInputs, p->vNodes, p->vOutputs );
// try solving the outputs
for ( i = f * Gia_ManPoNum(pGia); i < Gia_ManPoNum(p->pFrames); i++ )
{
Gia_Obj_t * pObj = Gia_ManPo(p->pFrames, i);
if ( Gia_ObjChild0(pObj) == Gia_ManConst0(p->pFrames) )
continue;
Lit = Abc_Var2Lit( Vec_IntEntry(p->vId2Var, Gia_ObjId(p->pFrames, pObj)), 0 );
status = sat_solver_solve( p->pSat, &Lit, &Lit + 1, (ABC_INT64_T)pPars->nConfLimit, (ABC_INT64_T)0, (ABC_INT64_T)0, (ABC_INT64_T)0 );
if ( status == l_False ) // unsat
continue;
if ( status == l_True ) // sat
RetValue = 0;
if ( status == l_Undef ) // undecided
RetValue = -1;
break;
}
}
// report statistics
if ( pPars->fVerbose )
{
printf( "%4d : PI =%9d. AIG =%9d. Var =%8d. In =%6d. And =%9d. Cla =%9d. Conf =%9d. Mem =%7.1f MB ",
f, Gia_ManPiNum(p->pFrames), Gia_ManAndNum(p->pFrames),
p->nSatVars-1, Vec_IntSize(p->vInputs), Vec_IntSize(p->vNodes),
sat_solver_nclauses(p->pSat), sat_solver_nconflicts(p->pSat), Gia_ManMemory(p->pFrames)/(1<<20) );
Abc_PrintTime( 1, "Time", Abc_Clock() - p->clkStart );
}
if ( RetValue != -2 )
{
if ( RetValue == -1 )
printf( "SAT solver reached conflict/runtime limit in frame %d.\n", f );
else
{
printf( "Output %d of miter \"%s\" was asserted in frame %d. ",
i - f * Gia_ManPoNum(pGia), Gia_ManName(pGia), f );
Abc_PrintTime( 1, "Time", Abc_Clock() - p->clkStart );
}
break;
}
}
if ( RetValue == -2 )
RetValue = -1;
// dump unfolded frames
if ( pPars->fDumpFrames )
{
p->pFrames = Gia_ManCleanup( p->pFrames );
Gia_AigerWrite( p->pFrames, "frames.aig", 0, 0 );
printf( "Dumped unfolded frames into file \"frames.aig\".\n" );
Gia_ManStop( p->pFrames );
}
// cleanup
Unr_ManFree( pUnroll );
Bmc_MnaFree( p );
return RetValue;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END
|
