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/**CFile****************************************************************
FileName [pdrTsim.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Property driven reachability.]
Synopsis [Improved ternary simulation.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - November 20, 2010.]
Revision [$Id: pdrTsim.c,v 1.00 2010/11/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "pdrInt.h"
#include "aig/gia/giaAig.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
struct Txs_Man_t_
{
Gia_Man_t * pGia; // user's AIG
Vec_Int_t * vPrio; // priority of each flop
Vec_Int_t * vCiObjs; // cone leaves (CI obj IDs)
Vec_Int_t * vCoObjs; // cone roots (CO obj IDs)
Vec_Int_t * vCiVals; // cone leaf values (0/1 CI values)
Vec_Int_t * vCoVals; // cone root values (0/1 CO values)
Vec_Int_t * vNodes; // cone nodes (node obj IDs)
Vec_Int_t * vPiLits; // resulting array of PI literals
Vec_Int_t * vFfLits; // resulting array of flop literals
Pdr_Man_t * pMan; // calling manager
};
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Start and stop the ternary simulation engine.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Txs_Man_t * Txs_ManStart( Pdr_Man_t * pMan, Aig_Man_t * pAig, Vec_Int_t * vPrio )
{
Txs_Man_t * p;
// Aig_Obj_t * pObj;
// int i;
assert( Vec_IntSize(vPrio) == Aig_ManRegNum(pAig) );
p = ABC_CALLOC( Txs_Man_t, 1 );
p->pGia = Gia_ManFromAigSimple(pAig); // user's AIG
// Aig_ManForEachObj( pAig, pObj, i )
// assert( i == 0 || pObj->iData == Abc_Var2Lit(i, 0) );
p->vPrio = vPrio; // priority of each flop
p->vCiObjs = Vec_IntAlloc( 100 ); // cone leaves (CI obj IDs)
p->vCoObjs = Vec_IntAlloc( 100 ); // cone roots (CO obj IDs)
p->vCiVals = Vec_IntAlloc( 100 ); // cone leaf values (0/1 CI values)
p->vCoVals = Vec_IntAlloc( 100 ); // cone root values (0/1 CO values)
p->vNodes = Vec_IntAlloc( 100 ); // cone nodes (node obj IDs)
p->vPiLits = Vec_IntAlloc( 100 ); // resulting array of PI literals
p->vFfLits = Vec_IntAlloc( 100 ); // resulting array of flop literals
p->pMan = pMan; // calling manager
return p;
}
void Txs_ManStop( Txs_Man_t * p )
{
Gia_ManStop( p->pGia );
Vec_IntFree( p->vCiObjs );
Vec_IntFree( p->vCoObjs );
Vec_IntFree( p->vCiVals );
Vec_IntFree( p->vCoVals );
Vec_IntFree( p->vNodes );
Vec_IntFree( p->vPiLits );
Vec_IntFree( p->vFfLits );
ABC_FREE( p );
}
/**Function*************************************************************
Synopsis [Marks the TFI cone and collects CIs and nodes.]
Description [For this procedure to work Value should not be ~0
at the beginning.]
SideEffects []
SeeAlso []
***********************************************************************/
void Txs_ManCollectCone_rec( Gia_Man_t * p, Gia_Obj_t * pObj, Vec_Int_t * vCiObjs, Vec_Int_t * vNodes )
{
if ( !~pObj->Value )
return;
pObj->Value = ~0;
if ( Gia_ObjIsCi(pObj) )
{
Vec_IntPush( vCiObjs, Gia_ObjId(p, pObj) );
return;
}
assert( Gia_ObjIsAnd(pObj) );
Txs_ManCollectCone_rec( p, Gia_ObjFanin0(pObj), vCiObjs, vNodes );
Txs_ManCollectCone_rec( p, Gia_ObjFanin1(pObj), vCiObjs, vNodes );
Vec_IntPush( vNodes, Gia_ObjId(p, pObj) );
}
void Txs_ManCollectCone( Gia_Man_t * p, Vec_Int_t * vCoObjs, Vec_Int_t * vCiObjs, Vec_Int_t * vNodes )
{
Gia_Obj_t * pObj; int i;
// printf( "Collecting cones for clause with %d literals.\n", Vec_IntSize(vCoObjs) );
Vec_IntClear( vCiObjs );
Vec_IntClear( vNodes );
Gia_ManConst0(p)->Value = ~0;
Gia_ManForEachObjVec( vCoObjs, p, pObj, i )
Txs_ManCollectCone_rec( p, Gia_ObjFanin0(pObj), vCiObjs, vNodes );
}
/**Function*************************************************************
Synopsis [Propagate values and assign priority.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Txs_ManForwardPass( Gia_Man_t * p,
Vec_Int_t * vPrio, Vec_Int_t * vCiObjs, Vec_Int_t * vCiVals,
Vec_Int_t * vNodes, Vec_Int_t * vCoObjs, Vec_Int_t * vCoVals )
{
Gia_Obj_t * pObj, * pFan0, * pFan1; int i;
pObj = Gia_ManConst0(p);
pObj->fMark0 = 0;
pObj->fMark1 = 0;
Gia_ManForEachObjVec( vCiObjs, p, pObj, i )
{
pObj->fMark0 = Vec_IntEntry(vCiVals, i);
pObj->fMark1 = 0;
pObj->Value = Gia_ObjIsPi(p, pObj) ? 0x7FFFFFFF : Vec_IntEntry(vPrio, Gia_ObjCioId(pObj)-Gia_ManPiNum(p));
assert( ~pObj->Value );
}
Gia_ManForEachObjVec( vNodes, p, pObj, i )
{
pFan0 = Gia_ObjFanin0(pObj);
pFan1 = Gia_ObjFanin1(pObj);
pObj->fMark0 = (pFan0->fMark0 ^ Gia_ObjFaninC0(pObj)) & (pFan1->fMark0 ^ Gia_ObjFaninC1(pObj));
pObj->fMark1 = 0;
if ( pObj->fMark0 )
pObj->Value = Abc_MinInt( pFan0->Value, pFan1->Value );
else if ( pFan0->fMark0 )
pObj->Value = pFan1->Value;
else if ( pFan1->fMark0 )
pObj->Value = pFan0->Value;
else // if ( pFan0->fMark0 == 0 && pFan1->fMark0 == 0 )
pObj->Value = Abc_MaxInt( pFan0->Value, pFan1->Value );
assert( ~pObj->Value );
}
Gia_ManForEachObjVec( vCoObjs, p, pObj, i )
{
pFan0 = Gia_ObjFanin0(pObj);
pObj->fMark0 = (pFan0->fMark0 ^ Gia_ObjFaninC0(pObj));
pFan0->fMark1 = 1;
assert( (int)pObj->fMark0 == Vec_IntEntry(vCoVals, i) );
}
}
/**Function*************************************************************
Synopsis [Propagate requirements and collect results.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline int Txs_ObjIsJust( Gia_Man_t * p, Gia_Obj_t * pObj )
{
Gia_Obj_t * pFan0 = Gia_ObjFanin0(pObj);
Gia_Obj_t * pFan1 = Gia_ObjFanin1(pObj);
int value0 = pFan0->fMark0 ^ Gia_ObjFaninC0(pObj);
int value1 = pFan1->fMark0 ^ Gia_ObjFaninC1(pObj);
assert( Gia_ObjIsAnd(pObj) );
if ( pObj->fMark0 )
return pFan0->fMark1 && pFan1->fMark1;
assert( !pObj->fMark0 );
assert( !value0 || !value1 );
if ( value0 )
return pFan1->fMark1;
if ( value1 )
return pFan0->fMark1;
assert( !value0 && !value1 );
return pFan0->fMark1 || pFan1->fMark1 || Gia_ObjIsPi(p, pFan0) || Gia_ObjIsPi(p, pFan1);
}
void Txs_ManBackwardPass( Gia_Man_t * p, Vec_Int_t * vCiObjs, Vec_Int_t * vNodes, Vec_Int_t * vPiLits, Vec_Int_t * vFfLits )
{
Gia_Obj_t * pObj, * pFan0, * pFan1; int i, value0, value1;
Gia_ManForEachObjVecReverse( vNodes, p, pObj, i )
{
if ( !pObj->fMark1 )
continue;
pFan0 = Gia_ObjFanin0(pObj);
pFan1 = Gia_ObjFanin1(pObj);
if ( pObj->fMark0 )
{
pFan0->fMark1 = 1;
pFan1->fMark1 = 1;
continue;
}
value0 = pFan0->fMark0 ^ Gia_ObjFaninC0(pObj);
value1 = pFan1->fMark0 ^ Gia_ObjFaninC1(pObj);
assert( !value0 || !value1 );
if ( value0 )
pFan1->fMark1 = 1;
else if ( value1 )
pFan0->fMark1 = 1;
else // if ( !value0 && !value1 )
{
if ( pFan0->fMark1 || pFan1->fMark1 )
continue;
if ( Gia_ObjIsPi(p, pFan0) )
pFan0->fMark1 = 1;
else if ( Gia_ObjIsPi(p, pFan1) )
pFan1->fMark1 = 1;
else if ( Gia_ObjIsAnd(pFan0) && Txs_ObjIsJust(p, pFan0) )
pFan0->fMark1 = 1;
else if ( Gia_ObjIsAnd(pFan1) && Txs_ObjIsJust(p, pFan1) )
pFan1->fMark1 = 1;
else
{
if ( pFan0->Value >= pFan1->Value )
pFan0->fMark1 = 1;
else
pFan1->fMark1 = 1;
}
}
}
Vec_IntClear( vPiLits );
Vec_IntClear( vFfLits );
Gia_ManForEachObjVec( vCiObjs, p, pObj, i )
{
if ( !pObj->fMark1 )
continue;
if ( Gia_ObjIsPi(p, pObj) )
Vec_IntPush( vPiLits, Abc_Var2Lit(Gia_ObjCioId(pObj), !pObj->fMark0) );
else
Vec_IntPush( vFfLits, Abc_Var2Lit(Gia_ObjCioId(pObj)-Gia_ManPiNum(p), !pObj->fMark0) );
}
assert( Vec_IntSize(vFfLits) > 0 );
}
/**Function*************************************************************
Synopsis [Verify the result.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Txs_ManVerify( Gia_Man_t * p, Vec_Int_t * vCiObjs, Vec_Int_t * vNodes, Vec_Int_t * vPiLits, Vec_Int_t * vFfLits, Vec_Int_t * vCoObjs, Vec_Int_t * vCoVals )
{
Gia_Obj_t * pObj;
int i, iLit;
Gia_ObjTerSimSet0( Gia_ManConst0(p) );
Gia_ManForEachObjVec( vCiObjs, p, pObj, i )
Gia_ObjTerSimSetX( pObj );
Vec_IntForEachEntry( vPiLits, iLit, i )
{
pObj = Gia_ManPi( p, Abc_Lit2Var(iLit) );
assert( Gia_ObjTerSimGetX(pObj) );
if ( Abc_LitIsCompl(iLit) )
Gia_ObjTerSimSet0( pObj );
else
Gia_ObjTerSimSet1( pObj );
}
Vec_IntForEachEntry( vFfLits, iLit, i )
{
pObj = Gia_ManCi( p, Gia_ManPiNum(p) + Abc_Lit2Var(iLit) );
assert( Gia_ObjTerSimGetX(pObj) );
if ( Abc_LitIsCompl(iLit) )
Gia_ObjTerSimSet0( pObj );
else
Gia_ObjTerSimSet1( pObj );
}
Gia_ManForEachObjVec( vNodes, p, pObj, i )
Gia_ObjTerSimAnd( pObj );
Gia_ManForEachObjVec( vCoObjs, p, pObj, i )
{
Gia_ObjTerSimCo( pObj );
if ( Vec_IntEntry(vCoVals, i) )
assert( Gia_ObjTerSimGet1(pObj) );
else
assert( Gia_ObjTerSimGet0(pObj) );
}
}
/**Function*************************************************************
Synopsis [Shrinks values using ternary simulation.]
Description [The cube contains the set of flop index literals which,
when converted into a clause and applied to the combinational outputs,
led to a satisfiable SAT run in frame k (values stored in the SAT solver).
If the cube is NULL, it is assumed that the first property output was
asserted and failed.
The resulting array is a set of flop index literals that asserts the COs.
Priority contains 0 for i-th entry if the i-th FF is desirable to remove.]
SideEffects []
SeeAlso []
***********************************************************************/
Pdr_Set_t * Txs_ManTernarySim( Txs_Man_t * p, int k, Pdr_Set_t * pCube )
{
Pdr_Set_t * pRes;
Gia_Obj_t * pObj;
// collect CO objects
Vec_IntClear( p->vCoObjs );
if ( pCube == NULL ) // the target is the property output
{
pObj = Gia_ManCo(p->pGia, p->pMan->iOutCur);
Vec_IntPush( p->vCoObjs, Gia_ObjId(p->pGia, pObj) );
}
else // the target is the cube
{
int i;
for ( i = 0; i < pCube->nLits; i++ )
{
if ( pCube->Lits[i] == -1 )
continue;
pObj = Gia_ManCo(p->pGia, Gia_ManPoNum(p->pGia) + Abc_Lit2Var(pCube->Lits[i]));
Vec_IntPush( p->vCoObjs, Gia_ObjId(p->pGia, pObj) );
}
}
if ( 0 )
{
Abc_Print( 1, "Trying to justify cube " );
if ( pCube )
Pdr_SetPrint( stdout, pCube, Gia_ManRegNum(p->pGia), NULL );
else
Abc_Print( 1, "<prop=fail>" );
Abc_Print( 1, " in frame %d.\n", k );
}
// collect CI objects
Txs_ManCollectCone( p->pGia, p->vCoObjs, p->vCiObjs, p->vNodes );
// collect values
Pdr_ManCollectValues( p->pMan, k, p->vCiObjs, p->vCiVals );
Pdr_ManCollectValues( p->pMan, k, p->vCoObjs, p->vCoVals );
// perform two passes
Txs_ManForwardPass( p->pGia, p->vPrio, p->vCiObjs, p->vCiVals, p->vNodes, p->vCoObjs, p->vCoVals );
Txs_ManBackwardPass( p->pGia, p->vCiObjs, p->vNodes, p->vPiLits, p->vFfLits );
Txs_ManVerify( p->pGia, p->vCiObjs, p->vNodes, p->vPiLits, p->vFfLits, p->vCoObjs, p->vCoVals );
// derive the final set
pRes = Pdr_SetCreate( p->vFfLits, p->vPiLits );
//ZH: Disabled assertion because this invariant doesn't hold with down
//because of the join operation which can bring in initial states
//assert( k == 0 || !Pdr_SetIsInit(pRes, -1) );
return pRes;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END
|
