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/**CFile****************************************************************
FileName [fraIndVer.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [New FRAIG package.]
Synopsis [Verification of the inductive invariant.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 30, 2007.]
Revision [$Id: fraIndVer.c,v 1.00 2007/06/30 00:00:00 alanmi Exp $]
***********************************************************************/
#include "fra.h"
#include "sat/cnf/cnf.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Verifies the inductive invariant.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Fra_InvariantVerify( Aig_Man_t * pAig, int nFrames, Vec_Int_t * vClauses, Vec_Int_t * vLits )
{
Cnf_Dat_t * pCnf;
sat_solver * pSat;
int * pStart;
int RetValue, Beg, End, i, k;
int CounterBase = 0, CounterInd = 0;
clock_t clk = clock();
if ( nFrames != 1 )
{
printf( "Invariant verification: Can only verify for K = 1\n" );
return 1;
}
// derive CNF
pCnf = Cnf_DeriveSimple( pAig, Aig_ManCoNum(pAig) );
/*
// add the property
{
Aig_Obj_t * pObj;
int Lits[1];
pObj = Aig_ManCo( pAig, 0 );
Lits[0] = toLitCond( pCnf->pVarNums[pObj->Id], 1 );
Vec_IntPush( vLits, Lits[0] );
Vec_IntPush( vClauses, Vec_IntSize(vLits) );
printf( "Added the target property to the set of clauses to be inductively checked.\n" );
}
*/
// derive initialized frames for the base case
pSat = (sat_solver *)Cnf_DataWriteIntoSolver( pCnf, nFrames, 1 );
// check clauses in the base case
Beg = 0;
pStart = Vec_IntArray( vLits );
Vec_IntForEachEntry( vClauses, End, i )
{
// complement the literals
for ( k = Beg; k < End; k++ )
pStart[k] = lit_neg(pStart[k]);
RetValue = sat_solver_solve( pSat, pStart + Beg, pStart + End, 0, 0, 0, 0 );
for ( k = Beg; k < End; k++ )
pStart[k] = lit_neg(pStart[k]);
Beg = End;
if ( RetValue == l_False )
continue;
// printf( "Clause %d failed the base case.\n", i );
CounterBase++;
}
sat_solver_delete( pSat );
// derive initialized frames for the base case
pSat = (sat_solver *)Cnf_DataWriteIntoSolver( pCnf, nFrames + 1, 0 );
assert( pSat->size == 2 * pCnf->nVars );
// add clauses to the first frame
Beg = 0;
pStart = Vec_IntArray( vLits );
Vec_IntForEachEntry( vClauses, End, i )
{
RetValue = sat_solver_addclause( pSat, pStart + Beg, pStart + End );
Beg = End;
if ( RetValue == 0 )
{
Cnf_DataFree( pCnf );
sat_solver_delete( pSat );
printf( "Invariant verification: SAT solver is unsat after adding a clause.\n" );
return 0;
}
}
// simplify the solver
if ( pSat->qtail != pSat->qhead )
{
RetValue = sat_solver_simplify(pSat);
assert( RetValue != 0 );
assert( pSat->qtail == pSat->qhead );
}
// check clauses in the base case
Beg = 0;
pStart = Vec_IntArray( vLits );
Vec_IntForEachEntry( vClauses, End, i )
{
// complement the literals
for ( k = Beg; k < End; k++ )
{
pStart[k] += 2 * pCnf->nVars;
pStart[k] = lit_neg(pStart[k]);
}
RetValue = sat_solver_solve( pSat, pStart + Beg, pStart + End, 0, 0, 0, 0 );
for ( k = Beg; k < End; k++ )
{
pStart[k] = lit_neg(pStart[k]);
pStart[k] -= 2 * pCnf->nVars;
}
Beg = End;
if ( RetValue == l_False )
continue;
// printf( "Clause %d failed the inductive case.\n", i );
CounterInd++;
}
sat_solver_delete( pSat );
Cnf_DataFree( pCnf );
if ( CounterBase )
printf( "Invariant verification: %d clauses (out of %d) FAILED the base case.\n", CounterBase, Vec_IntSize(vClauses) );
if ( CounterInd )
printf( "Invariant verification: %d clauses (out of %d) FAILED the inductive case.\n", CounterInd, Vec_IntSize(vClauses) );
if ( CounterBase || CounterInd )
return 0;
printf( "Invariant verification: %d clauses verified correctly. ", Vec_IntSize(vClauses) );
ABC_PRT( "Time", clock() - clk );
return 1;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END
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