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|
/**CFile****************************************************************
FileName [giaAbsVta.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Scalable AIG package.]
Synopsis [Variable time-frame abstraction.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: giaAbsVta.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "gia.h"
#include "satSolver2.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
typedef struct Vta_Obj_t_ Vta_Obj_t; // object
struct Vta_Obj_t_
{
int iObj;
int iFrame;
int iNext;
unsigned Prio : 24;
unsigned Value : 2;
unsigned fAdded : 1;
unsigned fNew : 1;
// unsigned fPi : 1;
// unsigned fConst : 1;
// int fFlop : 1;
// int fAnd : 1;
};
typedef struct Vta_Man_t_ Vta_Man_t; // manager
struct Vta_Man_t_
{
// user data
Gia_Man_t * pGia; // AIG manager
int nFramesMax; // maximum number of frames
int nConfMax; // conflict limit
int nTimeMax; // runtime limit
int fVerbose; // verbose flag
// internal data
int nObjs; // the number of objects
int nObjsAlloc; // the number of objects allocated
int nBins; // number of hash table entries
int * pBins; // hash table bins
Vta_Obj_t * pObjs; // hash table bins
// abstraction
int nWords; // the number of sim words for abs
int nFrames; // the number of copmleted frames
Vec_Int_t * vAbs; // abstraction
// other data
Vec_Int_t * vCla2Var; // map clauses into variables
sat_solver2 * pSat; // incremental SAT solver
};
static inline Vta_Obj_t * Vta_ManObj( Vta_Man_t * p, int i ) { assert( i >= 0 && i < p->nObjs ); return i ? p->pObjs + i : NULL; }
static inline int Vta_ObjId( Vta_Man_t * p, Vta_Obj_t * pObj ) { assert( pObj > p->pObjs && pObj < p->pObjs + p->nObjs ); return pObj - p->pObjs; }
static inline unsigned * Vta_ObjAbs( Vta_Man_t * p, int i ) { assert( i >= 0 && i < p->nObjs ); return (unsigned *)Vec_IntEntryP( p->vAbs, i*p->nWords ); }
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Detects how many frames are completed.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline int Vta_ManReadFrameStart( Vec_Int_t * p, int nWords )
{
unsigned * pTotal, * pThis;
int i, w, nObjs = Vec_IntSize(p) / nWords;
assert( Vec_IntSize(p) % nWords == 0 );
pTotal = ABC_CALLOC( unsigned, nWords );
for ( i = 0; i < nObjs; i++ )
{
pThis = (unsigned *)Vec_IntEntryP( p, nWords * i );
for ( w = 0; w < nWords; w++ )
pTotal[w] |= pThis[i];
}
for ( i = nWords * 32 - 1; i >= 0; i-- )
if ( Gia_InfoHasBit(pTotal, i) )
{
ABC_FREE( pTotal );
return i+1;
}
ABC_FREE( pTotal );
return -1;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Vta_Man_t * Vga_ManStart( Gia_Man_t * pGia, Vec_Int_t * vAbs, int nFramesMax, int nConfMax, int nTimeMax, int fVerbose )
{
Vta_Man_t * p;
assert( nFramesMax > 0 && nFramesMax < 32 );
p = ABC_CALLOC( Vta_Man_t, 1 );
p->pGia = pGia;
p->nFramesMax = nFramesMax;
p->nConfMax = nConfMax;
p->nTimeMax = nTimeMax;
p->fVerbose = fVerbose;
// internal data
p->nObjsAlloc = (1 << 20);
p->pObjs = ABC_CALLOC( Vta_Obj_t, p->nObjsAlloc );
p->nObjs = 1;
p->nBins = Gia_PrimeCudd( p->nObjsAlloc/2 );
p->pBins = ABC_CALLOC( int, p->nBins );
// abstraction
p->nWords = vAbs ? Vec_IntSize(vAbs) / Gia_ManObjNum(p->pGia) : 1;
p->nFrames = vAbs ? Vta_ManReadFrameStart( vAbs, p->nWords ) : 0;
p->vAbs = vAbs ? vAbs : Vec_IntStart( Gia_ManObjNum(p->pGia) * p->nWords );
// other data
p->vCla2Var = Vec_IntAlloc( 1000 );
p->pSat = sat_solver2_new();
assert( nFramesMax == 0 || p->nFrames < nFramesMax );
return p;
}
/**Function*************************************************************
Synopsis [Delete manager.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Vga_ManStop( Vta_Man_t * p )
{
assert( p->vAbs == NULL );
Vec_IntFreeP( &p->vCla2Var );
sat_solver2_delete( p->pSat );
ABC_FREE( p->pBins );
ABC_FREE( p->pObjs );
ABC_FREE( p );
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline int Vga_ManHash( int iObj, int iFrame, int nBins )
{
return ((iObj + iFrame)*(iObj + iFrame + 1)) % nBins;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline int * Vga_ManLookup( Vta_Man_t * p, int iObj, int iFrame )
{
Vta_Obj_t * pThis;
int * pPlace = p->pBins + Vga_ManHash( iObj, iFrame, p->nBins );
for ( pThis = Vta_ManObj(p, *pPlace);
pThis; pPlace = &pThis->iNext,
pThis = Vta_ManObj(p, *pPlace) )
if ( pThis->iObj == iObj && pThis->iFrame == iFrame )
break;
return pPlace;
}
static inline Vta_Obj_t * Vga_ManFind( Vta_Man_t * p, int iObj, int iFrame )
{
int * pPlace = Vga_ManLookup( p, iObj, iFrame );
return Vta_ManObj(p, *pPlace);
}
static inline Vta_Obj_t * Vga_ManFindOrAdd( Vta_Man_t * p, int iObj, int iFrame )
{
Vta_Obj_t * pThis;
int * pPlace;
if ( p->nObjs == p->nObjsAlloc )
{
p->pObjs = ABC_REALLOC( Vta_Obj_t, p->pObjs, 2 * p->nObjsAlloc );
memset( p->pObjs + p->nObjsAlloc, 0, p->nObjsAlloc * sizeof(Vta_Obj_t) );
p->nObjsAlloc *= 2;
// rehash entries in the table
}
pPlace = Vga_ManLookup( p, iObj, iFrame );
if ( *pPlace )
return Vta_ManObj(p, *pPlace);
*pPlace = p->nObjs++;
pThis = Vta_ManObj(p, *pPlace);
pThis->iObj = iObj;
pThis->iFrame = iFrame;
pThis->fNew = 1;
return pThis;
}
static inline void Vga_ManDelete( Vta_Man_t * p, int iObj, int iFrame )
{
int * pPlace = Vga_ManLookup( p, iObj, iFrame );
Vta_Obj_t * pThis = Vta_ManObj(p, *pPlace);
assert( pThis != NULL );
*pPlace = pThis->iNext;
pThis->iNext = -1;
}
/**Function*************************************************************
Synopsis [Adds clauses to the solver.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Vga_ManAddClauses( Vta_Man_t * p, int iObjStart )
{
Vta_Obj_t * pThis, * pThis0, * pThis1;
Gia_Obj_t * pObj;
int i;
for ( i = iObjStart; i < p->nObjs; i++ )
{
pThis = Vta_ManObj( p, i );
assert( !pThis->fAdded && !pThis->fNew );
pObj = Gia_ManObj( p->pGia, pThis->iObj );
if ( Gia_ObjIsAnd(pObj) )
{
pThis0 = Vga_ManFind( p, Gia_ObjFaninId0p(p->pGia, pObj), pThis->iFrame );
pThis1 = Vga_ManFind( p, Gia_ObjFaninId1p(p->pGia, pObj), pThis->iFrame );
if ( pThis0 && pThis1 )
{
pThis->fAdded = 1;
sat_solver2_add_and( p->pSat,
Vta_ObjId(p, pThis), Vta_ObjId(p, pThis0), Vta_ObjId(p, pThis1),
Gia_ObjFaninC0(pObj), Gia_ObjFaninC1(pObj), 0 );
Vec_IntPush( p->vCla2Var, i );
Vec_IntPush( p->vCla2Var, i );
Vec_IntPush( p->vCla2Var, i );
}
}
else if ( Gia_ObjIsRo(p->pGia, pObj) )
{
if ( pThis->iFrame == 0 )
{
pThis->fAdded = 1;
sat_solver2_add_constraint( p->pSat, pThis->iObj, 1, 0 );
Vec_IntPush( p->vCla2Var, i );
Vec_IntPush( p->vCla2Var, i );
}
else
{
pObj = Gia_ObjRoToRi( p->pGia, pObj );
pThis0 = Vga_ManFind( p, Gia_ObjFaninId0p(p->pGia, pObj), pThis->iFrame-1 );
if ( pThis0 )
{
pThis->fAdded = 1;
sat_solver2_add_buffer( p->pSat,
Vta_ObjId(p, pThis), Vta_ObjId(p, pThis0),
Gia_ObjFaninC0(pObj), 0 );
Vec_IntPush( p->vCla2Var, i );
Vec_IntPush( p->vCla2Var, i );
}
}
}
else if ( Gia_ObjIsConst0(pObj) )
{
pThis->fAdded = 1;
sat_solver2_add_const( p->pSat, Vta_ObjId(p, pThis), 1, 0 );
Vec_IntPush( p->vCla2Var, i );
}
else if ( !Gia_ObjIsPi(p->pGia, pObj) )
assert( 0 );
}
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline void Vga_ManUnroll_rec( Vta_Man_t * p, int iObj, int iFrame )
{
Gia_Obj_t * pObj;
Vta_Obj_t * pThis = Vga_ManFindOrAdd( p, iObj, iFrame );
assert( !Gia_ObjIsCo(pObj) );
if ( !pThis->fNew )
return;
pThis->fNew = 0;
pObj = Gia_ManObj( p->pGia, iObj );
if ( Gia_ObjIsAnd(pObj) )
{
Vga_ManUnroll_rec( p, Gia_ObjFaninId0p(p->pGia, pObj), iFrame );
Vga_ManUnroll_rec( p, Gia_ObjFaninId1p(p->pGia, pObj), iFrame );
}
else if ( Gia_ObjIsRo(p->pGia, pObj) )
{
if ( iFrame == 0 )
{
pThis = Vga_ManFindOrAdd( p, iObj, -1 );
assert( pThis->fNew );
pThis->fNew = 0;
}
else
{
pObj = Gia_ObjRoToRi( p->pGia, pObj );
Vga_ManUnroll_rec( p, Gia_ObjFaninId0p(p->pGia, pObj), iFrame-1 );
}
}
else if ( Gia_ObjIsPi(p->pGia, pObj) )
{}
else if ( Gia_ObjIsConst0(pObj) )
{}
else assert( 0 );
}
/**Function*************************************************************
Synopsis [Finds the set of clauses involved in the UNSAT core.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Vec_Int_t * Vta_ManUnsatCore( sat_solver2 * pSat, int nConfMax, int fVerbose, int * piRetValue )
{
Vec_Int_t * vCore;
int RetValue, clk = clock();
if ( piRetValue )
*piRetValue = -1;
// solve the problem
RetValue = sat_solver2_solve( pSat, NULL, NULL, (ABC_INT64_T)nConfMax, (ABC_INT64_T)0, (ABC_INT64_T)0, (ABC_INT64_T)0 );
if ( RetValue == l_Undef )
{
// if ( fVerbose )
printf( "Conflict limit is reached.\n" );
return NULL;
}
if ( RetValue == l_True )
{
// if ( fVerbose )
printf( "The BMC problem is SAT.\n" );
if ( piRetValue )
*piRetValue = 0;
return NULL;
}
if ( fVerbose )
{
printf( "UNSAT after %7d conflicts. ", pSat->stats.conflicts );
Abc_PrintTime( 1, "Time", clock() - clk );
}
assert( RetValue == l_False );
// derive the UNSAT core
clk = clock();
vCore = (Vec_Int_t *)Sat_ProofCore( pSat );
if ( fVerbose )
{
printf( "Core is %8d clauses (out of %8d). ", Vec_IntSize(vCore), sat_solver2_nclauses(pSat) );
Abc_PrintTime( 1, "Time", clock() - clk );
}
return vCore;
}
/**Function*************************************************************
Synopsis [Collect nodes/flops involved in different timeframes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Vec_IntDoubleWidth( Vec_Int_t * p, int nWords )
{
int * pArray = ABC_CALLOC( int, Vec_IntSize(p) * 2 );
int i, w, nObjs = Vec_IntSize(p) / nWords;
assert( Vec_IntSize(p) % nWords == 0 );
for ( i = 0; i < nObjs; i++ )
for ( w = 0; w < nWords; w++ )
pArray[2 * nWords * i + w] = p->pArray[nWords * i + w];
ABC_FREE( p->pArray );
p->pArray = pArray;
p->nSize *= 2;
p->nCap = p->nSize;
}
/**Function*************************************************************
Synopsis [Collect nodes/flops involved in different timeframes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Gia_VtaTest( Gia_Man_t * pAig, int nFramesMax, int nConfMax, int nTimeMax, int fVerbose )
{
Vta_Man_t * p;
Gia_Obj_t * pObj;
Vec_Int_t * vCore;
Vec_Int_t * vAbs = NULL;
int f, i, iObjPrev, RetValue, Entry;
assert( Gia_ManPoNum(pAig) == 1 );
pObj = Gia_ManPo( pAig, 0 );
// start the manager
p = Vga_ManStart( pAig, vAbs, nFramesMax, nConfMax, nTimeMax, fVerbose );
// iteragte though time frames
for ( f = p->nFrames; f < nFramesMax; f++ )
{
if ( fVerbose )
printf( "Frame %4d : ", f );
if ( p->nWords * 32 == f )
{
Vec_IntDoubleWidth( vAbs, p->nWords );
p->nWords *= 2;
}
iObjPrev = p->nObjs;
Vga_ManUnroll_rec( p, Gia_ObjFaninId0p(p->pGia, pObj), f );
Vga_ManAddClauses( p, iObjPrev );
// run SAT solver
vCore = Vta_ManUnsatCore( p->pSat, nConfMax, fVerbose, &RetValue );
if ( vCore == NULL )
break;
// add core to storage
Vec_IntForEachEntry( vCore, Entry, i )
Gia_InfoSetBit( Vta_ObjAbs(p, Vec_IntEntry(p->vCla2Var, Entry)), f );
Vec_IntFree( vCore );
}
vAbs = p->vAbs; p->vAbs = NULL;
Vga_ManStop( p );
// print statistics about the core
Vec_IntFree( vAbs );
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END
|
