Version abc80511

abc.dsp

@@ -3254,6 +3254,14 @@ SOURCE=.\src\aig\saig\saig.h
 # End Source File
 # Begin Source File
 
+SOURCE=.\src\aig\saig\saigBmc.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\src\aig\saig\saigCone.c
+# End Source File
+# Begin Source File
+
 SOURCE=.\src\aig\saig\saigInter.c
 # End Source File
 # Begin Source File

abc.rc

@@ -35,6 +35,7 @@ alias fr fretime
 alias ft fraig_trust
 alias ic indcut
 alias lp lutpack
+alias pcon print_cone
 alias pd print_dsd
 alias pex print_exdc -d
 alias pf print_factor

src/aig/dar/darBalance.c

@@ -70,7 +70,7 @@ int Dar_BalanceCone_rec( Aig_Obj_t * pRoot, Aig_Obj_t * pObj, Vec_Ptr_t * vSuper
         return 0;
     }
     // if the new node is complemented or a PI, another gate begins
-    if ( pObj != pRoot && (Aig_IsComplement(pObj) || Aig_ObjType(pObj) != Aig_ObjType(pRoot) || Aig_ObjRefs(pObj) > 1) )
+    if ( pObj != pRoot && (Aig_IsComplement(pObj) || Aig_ObjType(pObj) != Aig_ObjType(pRoot) || Aig_ObjRefs(pObj) > 1 || Vec_PtrSize(vSuper) > 10000) )
     {
         Vec_PtrPush( vSuper, pObj );
         Aig_Regular(pObj)->fMarkB = 1;

src/aig/dar/darLib.c

@@ -770,7 +770,7 @@ void Dar_LibObjPrint_rec( Dar_LibObj_t * pObj )
   SeeAlso     []
 
 ***********************************************************************/
-void Dar_LibEvalAssignNums( Dar_Man_t * p, int Class )
+void Dar_LibEvalAssignNums( Dar_Man_t * p, int Class, Aig_Obj_t * pRoot )
 {
     Dar_LibObj_t * pObj;
     Dar_LibDat_t * pData, * pData0, * pData1;
@@ -797,13 +797,15 @@ void Dar_LibEvalAssignNums( Dar_Man_t * p, int Class )
             continue;
         pFanin0 = Aig_NotCond( pData0->pFunc, pObj->fCompl0 );
         pFanin1 = Aig_NotCond( pData1->pFunc, pObj->fCompl1 );
+        if ( Aig_Regular(pFanin0) == pRoot || Aig_Regular(pFanin1) == pRoot )
+            continue;
         pData->pFunc = Aig_TableLookupTwo( p->pAig, pFanin0, pFanin1 );
         if ( pData->pFunc )
         {
             // update the level to be more accurate
             pData->Level = Aig_Regular(pData->pFunc)->Level;
             // mark the node if it is part of MFFC
-            pData->fMffc = Aig_ObjIsTravIdCurrent(p->pAig, pData->pFunc);
+            pData->fMffc = Aig_ObjIsTravIdCurrent(p->pAig, Aig_Regular(pData->pFunc));
         }
     }
 }
@@ -871,7 +873,7 @@ void Dar_LibEval( Dar_Man_t * p, Aig_Obj_t * pRoot, Dar_Cut_t * pCut, int Requir
     nNodesSaved = Dar_LibCutMarkMffc( p->pAig, pRoot, pCut->nLeaves );
     // evaluate the cut
     Class = s_DarLib->pMap[pCut->uTruth];
-    Dar_LibEvalAssignNums( p, Class );
+    Dar_LibEvalAssignNums( p, Class, pRoot );
     // profile outputs by their savings
     p->nTotalSubgs += s_DarLib->nSubgr0[Class];
     p->ClassSubgs[Class] += s_DarLib->nSubgr0[Class];

src/aig/dar/darScript.c

@@ -91,6 +91,7 @@ Aig_Man_t * Dar_ManRwsat( Aig_Man_t * pAig, int fBalance, int fVerbose )
     if ( fVerbose ) Aig_ManPrintStats( pAig );
     }
    
+//Aig_ManDumpBlif( pAig, "inter.blif", NULL, NULL );
     // rewrite
     Dar_ManRewrite( pAig, pParsRwr );
     pAig = Aig_ManDupDfs( pTemp = pAig ); 

src/aig/fra/fraBmc.c

@@ -382,17 +382,36 @@ void Fra_BmcPerformSimple( Aig_Man_t * pAig, int nFrames, int nBTLimit, int fRew
     Fra_Man_t * pTemp;
     Fra_Bmc_t * pBmc;
     Aig_Man_t * pAigTemp;
-    int iOutput;
+    int clk, iOutput;
     // derive and fraig the frames
+    clk = clock();
     pBmc = Fra_BmcStart( pAig, 0, nFrames );
     pTemp = Fra_LcrAigPrepare( pAig );
     pTemp->pBmc = pBmc;
     pBmc->pAigFrames = Fra_BmcFrames( pBmc, 1 );
+    if ( fVerbose )
+    {
+        printf( "AIG:  PI/PO/Reg = %d/%d/%d.  Node = %6d. Lev = %5d.\n", 
+            Aig_ManPiNum(pAig)-Aig_ManRegNum(pAig), Aig_ManPoNum(pAig)-Aig_ManRegNum(pAig), Aig_ManRegNum(pAig),
+            Aig_ManNodeNum(pAig), Aig_ManLevelNum(pAig) );
+        printf( "Time-frames (%d):  PI/PO = %d/%d.  Node = %6d. Lev = %5d.  ", 
+            nFrames, Aig_ManPiNum(pBmc->pAigFrames), Aig_ManPoNum(pBmc->pAigFrames), 
+            Aig_ManNodeNum(pBmc->pAigFrames), Aig_ManLevelNum(pBmc->pAigFrames) );
+        PRT( "Time", clock() - clk );
+    }
     if ( fRewrite )
     {
+        clk = clock();
         pBmc->pAigFrames = Dar_ManRwsat( pAigTemp = pBmc->pAigFrames, 1, 0 );
         Aig_ManStop( pAigTemp );
+        if ( fVerbose )
+        {
+            printf( "Time-frames after rewriting:  Node = %6d. Lev = %5d.  ", 
+                Aig_ManNodeNum(pBmc->pAigFrames), Aig_ManLevelNum(pBmc->pAigFrames) );
+            PRT( "Time", clock() - clk );
+        }
     }
+    clk = clock();
     iOutput = Fra_FraigMiterAssertedOutput( pBmc->pAigFrames );
     if ( iOutput >= 0 )
         pAig->pSeqModel = Fra_SmlTrivCounterExample( pAig, iOutput );
@@ -409,8 +428,12 @@ void Fra_BmcPerformSimple( Aig_Man_t * pAig, int nFrames, int nBTLimit, int fRew
             pAig->pSeqModel = Fra_SmlTrivCounterExample( pAig, iOutput );
     }
     if ( fVerbose )
-        printf( "nFrames = %3d. Aig = %6d. Init frames = %6d. Fraiged init frames = %6d.\n", 
-            nFrames, Aig_ManNodeNum(pAig), Aig_ManNodeNum(pBmc->pAigFrames), pBmc->pAigFraig? Aig_ManNodeNum(pBmc->pAigFraig) : -1 );
+    {
+        printf( "Fraiged init frames: Node = %6d. Lev = %5d.  ", 
+            pBmc->pAigFraig? Aig_ManNodeNum(pBmc->pAigFraig) : -1,
+            pBmc->pAigFraig? Aig_ManLevelNum(pBmc->pAigFraig) : -1 );
+        PRT( "Time", clock() - clk );
+    }
     Fra_BmcStop( pBmc );  
     free( pTemp );
 }

src/aig/hop/hopBalance.c

@@ -148,7 +148,7 @@ int Hop_NodeBalanceCone_rec( Hop_Obj_t * pRoot, Hop_Obj_t * pObj, Vec_Ptr_t * vS
         return 0;
     }
     // if the new node is complemented or a PI, another gate begins
-    if ( pObj != pRoot && (Hop_IsComplement(pObj) || Hop_ObjType(pObj) != Hop_ObjType(pRoot) || Hop_ObjRefs(pObj) > 1) )
+    if ( pObj != pRoot && (Hop_IsComplement(pObj) || Hop_ObjType(pObj) != Hop_ObjType(pRoot) || Hop_ObjRefs(pObj) > 1 || Vec_PtrSize(vSuper) > 10000) )
     {
         Vec_PtrPush( vSuper, pObj );
         Hop_Regular(pObj)->fMarkB = 1;

src/aig/ivy/ivyBalance.c

@@ -215,7 +215,7 @@ int Ivy_NodeBalanceCone_rec( Ivy_Obj_t * pRoot, Ivy_Obj_t * pObj, Vec_Ptr_t * vS
         return 0;
     }
     // if the new node is complemented or a PI, another gate begins
-    if ( pObj != pRoot && (Ivy_IsComplement(pObj) || Ivy_ObjType(pObj) != Ivy_ObjType(pRoot) || Ivy_ObjRefs(pObj) > 1) )
+    if ( pObj != pRoot && (Ivy_IsComplement(pObj) || Ivy_ObjType(pObj) != Ivy_ObjType(pRoot) || Ivy_ObjRefs(pObj) > 1 || Vec_PtrSize(vSuper) > 10000) )
     {
         Vec_PtrPush( vSuper, pObj );
         Ivy_Regular(pObj)->fMarkB = 1;

src/aig/saig/module.make

-SRC +=    src/aig/saig/saig_.c \
+SRC +=    src/aig/saig/saigBmc.c \
+    src/aig/saig/saigCone.c \
     src/aig/saig/saigInter.c \
     src/aig/saig/saigPhase.c \
     src/aig/saig/saigRetFwd.c \

src/aig/saig/saig.h

@@ -75,8 +75,12 @@ static inline int          Saig_ObjIsLi( Aig_Man_t * p, Aig_Obj_t * pObj )    {
 ///                    FUNCTION DECLARATIONS                         ///
 ////////////////////////////////////////////////////////////////////////
 
+/*=== saigBmc.c ==========================================================*/
+extern int               Saig_ManBmcSimple( Aig_Man_t * pAig, int nFrames, int nBTLimit, int fRewrite, int fVerbose, int * piFrame );
+/*=== saigCone.c ==========================================================*/
+extern void              Saig_ManPrintCones( Aig_Man_t * p );
 /*=== saigInter.c ==========================================================*/
-extern int               Saig_Interpolate( Aig_Man_t * pAig, int nConfLimit, int fVerbose, int * pDepth );
+extern int               Saig_Interpolate( Aig_Man_t * pAig, int nConfLimit, int fRewrite, int fTransLoop, int fVerbose, int * pDepth );
 /*=== saigPhase.c ==========================================================*/
 extern Aig_Man_t *       Saig_ManPhaseAbstract( Aig_Man_t * p, Vec_Int_t * vInits, int nFrames, int fIgnore, int fPrint, int fVerbose );
 /*=== saigRetFwd.c ==========================================================*/

src/aig/saig/saigBmc.c

+/**CFile****************************************************************
+
+  FileName    [saigBmc.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Sequential AIG package.]
+
+  Synopsis    [Simple BMC package.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - June 20, 2005.]
+
+  Revision    [$Id: saigBmc.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "saig.h"
+#include "cnf.h"
+#include "satStore.h"
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Create timeframes of the manager for BMC.]
+
+  Description [The resulting manager is combinational. The primary inputs
+  corresponding to register outputs are ordered first. POs correspond to \
+  the property outputs in each time-frame.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Aig_Man_t * Saig_ManFramesBmc( Aig_Man_t * pAig, int nFrames )
+{
+    Aig_Man_t * pFrames;
+    Aig_Obj_t * pObj, * pObjLi, * pObjLo;
+    int i, f;
+    assert( Saig_ManRegNum(pAig) > 0 );
+    pFrames = Aig_ManStart( Aig_ManNodeNum(pAig) * nFrames );
+    // map the constant node
+    Aig_ManConst1(pAig)->pData = Aig_ManConst1( pFrames );
+    // create variables for register outputs
+    Saig_ManForEachLo( pAig, pObj, i )
+        pObj->pData = Aig_ManConst0( pFrames );
+    // add timeframes
+    for ( f = 0; f < nFrames; f++ )
+    {
+        // create PI nodes for this frame
+        Saig_ManForEachPi( pAig, pObj, i )
+            pObj->pData = Aig_ObjCreatePi( pFrames );
+        // add internal nodes of this frame
+        Aig_ManForEachNode( pAig, pObj, i )
+            pObj->pData = Aig_And( pFrames, Aig_ObjChild0Copy(pObj), Aig_ObjChild1Copy(pObj) );
+        // create POs for this frame
+        Saig_ManForEachPo( pAig, pObj, i )
+            Aig_ObjCreatePo( pFrames, Aig_ObjChild0Copy(pObj) );
+        if ( f == nFrames - 1 )
+            break;
+        // save register inputs
+        Saig_ManForEachLi( pAig, pObj, i )
+            pObj->pData = Aig_ObjChild0Copy(pObj);
+        // transfer to register outputs
+        Saig_ManForEachLiLo(  pAig, pObjLi, pObjLo, i )
+            pObjLo->pData = pObjLi->pData;
+    }
+    Aig_ManCleanup( pFrames );
+    return pFrames;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Performs BMC for the given AIG.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Saig_ManBmcSimple( Aig_Man_t * pAig, int nFrames, int nConfLimit, int fRewrite, int fVerbose, int * piFrame )
+{
+    sat_solver * pSat;
+    Cnf_Dat_t * pCnf;
+    Aig_Man_t * pFrames, * pAigTemp;
+    Aig_Obj_t * pObj;
+    int status, clk, Lit, i, RetValue = 1;
+    *piFrame = -1;
+    // derive the timeframes
+    clk = clock();
+    pFrames = Saig_ManFramesBmc( pAig, nFrames );
+    if ( fVerbose )
+    {
+        printf( "AIG:  PI/PO/Reg = %d/%d/%d.  Node = %6d. Lev = %5d.\n", 
+            Saig_ManPiNum(pAig), Saig_ManPoNum(pAig), Saig_ManRegNum(pAig),
+            Aig_ManNodeNum(pAig), Aig_ManLevelNum(pAig) );
+        printf( "Time-frames (%d):  PI/PO = %d/%d.  Node = %6d. Lev = %5d.  ", 
+            nFrames, Aig_ManPiNum(pFrames), Aig_ManPoNum(pFrames), 
+            Aig_ManNodeNum(pFrames), Aig_ManLevelNum(pFrames) );
+        PRT( "Time", clock() - clk );
+    }
+    // rewrite the timeframes
+    if ( fRewrite )
+    {
+        clk = clock();
+//        pFrames = Dar_ManBalance( pAigTemp = pFrames, 0 );
+        pFrames = Dar_ManRwsat( pAigTemp = pFrames, 1, 0 );
+        Aig_ManStop( pAigTemp );
+        if ( fVerbose )
+        {
+            printf( "Time-frames after rewriting:  Node = %6d. Lev = %5d.  ", 
+                Aig_ManNodeNum(pFrames), Aig_ManLevelNum(pFrames) );
+            PRT( "Time", clock() - clk );
+        }
+    }
+    // create the SAT solver
+    clk = clock();
+    pCnf = Cnf_Derive( pFrames, Aig_ManPoNum(pFrames) );  
+    pSat = sat_solver_new();
+    sat_solver_setnvars( pSat, pCnf->nVars );
+    for ( i = 0; i < pCnf->nClauses; i++ )
+    {
+        if ( !sat_solver_addclause( pSat, pCnf->pClauses[i], pCnf->pClauses[i+1] ) )
+            assert( 0 );
+    }
+    if ( fVerbose )
+    {
+        printf( "CNF: Variables = %6d. Clauses = %7d. Literals = %8d. ", pCnf->nVars, pCnf->nClauses, pCnf->nLiterals );
+        PRT( "Time", clock() - clk );
+    }
+    status = sat_solver_simplify(pSat);
+    if ( status == 0 )
+    {
+        if ( fVerbose )
+            printf( "The BMC problem is trivially UNSAT\n" );
+    }
+    else
+    {
+        Aig_ManForEachPo( pFrames, pObj, i )
+        {
+            Lit = toLitCond( pCnf->pVarNums[pObj->Id], 0 );
+            if ( fVerbose )
+                printf( "Solving output %2d of frame %3d ... \r", 
+                    i % Saig_ManPoNum(pAig), i / Saig_ManPoNum(pAig) );
+            clk = clock();
+            status = sat_solver_solve( pSat, &Lit, &Lit + 1, (sint64)nConfLimit, (sint64)0, (sint64)0, (sint64)0 );
+            if ( fVerbose )
+            {
+                printf( "Solved  output %2d of frame %3d.  ", 
+                    i % Saig_ManPoNum(pAig), i / Saig_ManPoNum(pAig) );
+                printf( "Conf =%8.0f. Imp =%11.0f. ", (double)pSat->stats.conflicts, (double)pSat->stats.propagations );
+                PRT( "Time", clock() - clk );
+            }
+            if ( status == l_False )
+            {
+            }
+            else if ( status == l_True )
+            {
+                extern void * Fra_SmlCopyCounterExample( Aig_Man_t * pAig, Aig_Man_t * pFrames, int * pModel );
+                Vec_Int_t * vCiIds = Cnf_DataCollectPiSatNums( pCnf, pFrames );
+                int * pModel = Sat_SolverGetModel( pSat, vCiIds->pArray, vCiIds->nSize );
+                pModel[Aig_ManPiNum(pFrames)] = pObj->Id;
+                pAig->pSeqModel = Fra_SmlCopyCounterExample( pAig, pFrames, pModel );
+                free( pModel );
+                Vec_IntFree( vCiIds );
+
+                RetValue = 0;
+                break;
+            }
+            else
+            {
+                *piFrame = i;
+                RetValue = -1;
+                break;
+            }
+        }
+    }
+    sat_solver_delete( pSat );
+    Cnf_DataFree( pCnf );
+    Aig_ManStop( pFrames );
+    return RetValue;
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+

src/aig/saig/saigCone.c

+/**CFile****************************************************************
+
+  FileName    [saigCone.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Sequential AIG package.]
+
+  Synopsis    [Cone of influence computation.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - June 20, 2005.]
+
+  Revision    [$Id: saigCone.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "saig.h"
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Counts the support size of the node.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Saig_ManSupport_rec( Aig_Man_t * p, Aig_Obj_t * pObj, Vec_Ptr_t * vSupp )
+{
+    if ( Aig_ObjIsTravIdCurrent(p, pObj) )
+        return;
+    Aig_ObjSetTravIdCurrent(p, pObj);
+    if ( Aig_ObjIsConst1(pObj) )
+        return;
+    if ( Aig_ObjIsPi(pObj) )
+    {
+        if ( Saig_ObjIsLo(p,pObj) )
+        {
+            pObj = Saig_ManLi( p, Aig_ObjPioNum(pObj)-Saig_ManPiNum(p) );
+            Vec_PtrPush( vSupp, pObj );
+        }
+        return;
+    }
+    assert( Aig_ObjIsNode(pObj) );
+    Saig_ManSupport_rec( p, Aig_ObjFanin0(pObj), vSupp );
+    Saig_ManSupport_rec( p, Aig_ObjFanin1(pObj), vSupp );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Counts the support size of the node.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Ptr_t * Saig_ManSupport( Aig_Man_t * p, Vec_Ptr_t * vNodes )
+{
+    Vec_Ptr_t * vSupp;
+    Aig_Obj_t * pObj;
+    int i;
+    vSupp = Vec_PtrAlloc( 100 );
+    Aig_ManIncrementTravId( p );
+    Vec_PtrForEachEntry( vNodes, pObj, i )
+    {
+        assert( Aig_ObjIsPo(pObj) );
+        Saig_ManSupport_rec( p, Aig_ObjFanin0(pObj), vSupp );
+    }
+    return vSupp;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Prints information about cones of influence of the POs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Saig_ManPrintConeOne( Aig_Man_t * p, Aig_Obj_t * pObj )
+{
+    Vec_Ptr_t * vPrev, * vCur, * vTotal;
+    int s, i, nCurNew, nCurPrev, nCurOld;
+    assert( Saig_ObjIsPo(p, pObj) );
+    // start the array
+    vPrev = Vec_PtrAlloc( 100 );
+    Vec_PtrPush( vPrev, pObj );
+    // get the current support
+    vCur = Saig_ManSupport( p, vPrev );  
+    Vec_PtrClear( vPrev );
+    printf( "    PO %3d  ", Aig_ObjPioNum(pObj) );
+    // continue computing supports as long as there are now nodes
+    vTotal = Vec_PtrAlloc( 100 );
+    for ( s = 0; ; s++ )
+    {
+        // classify current into those new, prev, and older 
+        nCurNew = nCurPrev = nCurOld = 0;
+        Vec_PtrForEachEntry( vCur, pObj, i )
+        {
+            if ( Vec_PtrFind(vTotal, pObj) == -1 )
+            {
+                Vec_PtrPush( vTotal, pObj );
+                nCurNew++;
+            }
+            else if ( Vec_PtrFind(vPrev, pObj) >= 0 )
+                nCurPrev++;
+            else
+                nCurOld++;
+        }
+        assert( nCurNew + nCurPrev + nCurOld == Vec_PtrSize(vCur) );
+        // print the result
+        printf( "%d:%d %d=%d+%d+%d  ", s, Vec_PtrSize(vTotal), Vec_PtrSize(vCur), nCurNew, nCurPrev, nCurOld ); 
+        if ( nCurNew == 0 )
+            break;
+        // compute one more step
+        Vec_PtrFree( vPrev );
+        vCur = Saig_ManSupport( p, vPrev = vCur );
+    }
+    printf( "\n" );
+    Vec_PtrFree( vPrev );
+    Vec_PtrFree( vCur );
+    Vec_PtrFree( vTotal );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Prints information about cones of influence of the POs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Saig_ManPrintCones( Aig_Man_t * p )
+{
+    Aig_Obj_t * pObj;
+    int i;
+    printf( "The format of this print-out: For each PO, x:a b=c+d+e, where \n" );
+    printf( "- x is the time-frame counting back from the PO\n" );
+    printf( "- a is the total number of registers in the COI of the PO so far\n" );
+    printf( "- b is the number of registers in the COI of the PO in this time-frame\n" );
+    printf( "- c is the number of registers in b that are new (appear for the first time)\n" );
+    printf( "- d is the number of registers in b in common with the previous time-frame\n" );
+    printf( "- e is the number of registers in b in common with other time-frames\n" );
+    Aig_ManSetPioNumbers( p );
+    Saig_ManForEachPo( p, pObj, i )
+        Saig_ManPrintConeOne( p, pObj );
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+

src/aig/saig/saigInter.c

@@ -23,15 +23,14 @@
 #include "cnf.h"
 #include "satStore.h"
 
-////////////////////////////////////////////////////////////////////////
-///                        DECLARATIONS                              ///
-////////////////////////////////////////////////////////////////////////
-
 /* 
     The interpolation algorithm implemented here was introduced in the paper:
     K. L. McMillan. Interpolation and SAT-based model checking. CAV’03, pp. 1-13.
 */
 
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
 
 // simulation manager
 typedef struct Saig_IntMan_t_ Saig_IntMan_t;
@@ -203,8 +202,8 @@ Aig_Man_t * Saig_ManFramesInter( Aig_Man_t * pAig, int nFrames )
     Aig_Man_t * pFrames;
     Aig_Obj_t * pObj, * pObjLi, * pObjLo;
     int i, f;
+    assert( Saig_ManRegNum(pAig) > 0 );
     assert( Saig_ManPoNum(pAig) == 1 );
-    // start the fraig package
     pFrames = Aig_ManStart( Aig_ManNodeNum(pAig) * nFrames );
     // map the constant node
     Aig_ManConst1(pAig)->pData = Aig_ManConst1( pFrames );
@@ -265,7 +264,7 @@ sat_solver * Saig_DeriveSatSolver(
     assert( Aig_ManPoNum(pInter) == 1 );
     assert( Aig_ManPoNum(pFrames) == 1 );
     assert( Aig_ManPiNum(pInter) == Aig_ManRegNum(pAig) );
-    assert( (Aig_ManPiNum(pFrames) - Aig_ManRegNum(pAig)) % Saig_ManPiNum(pAig) == 0 );
+//    assert( (Aig_ManPiNum(pFrames) - Aig_ManRegNum(pAig)) % Saig_ManPiNum(pAig) == 0 );
 
     // prepare CNFs
     Cnf_DataLift( pCnfAig,   pCnfFrames->nVars );
@@ -354,7 +353,7 @@ int Saig_PerformOneStep( Saig_IntMan_t * p )
 
     // derive the SAT solver
     pSat = Saig_DeriveSatSolver( p->pInter, p->pCnfInter, p->pAigTrans, p->pCnfAig, p->pFrames, p->pCnfFrames, p->vVarsAB );
-Sat_SolverWriteDimacs( pSat, "test.cnf", NULL, NULL, 1 );
+//Sat_SolverWriteDimacs( pSat, "test.cnf", NULL, NULL, 1 );
     // solve the problem
 clk = clock();
     status = sat_solver_solve( pSat, NULL, NULL, (sint64)p->nConfLimit, (sint64)0, (sint64)0, (sint64)0 );
@@ -403,14 +402,15 @@ int Saig_ManCheckContainment( Aig_Man_t * pNew, Aig_Man_t * pOld )
     Aig_Man_t * pMiter, * pAigTemp;
     int RetValue;
     pMiter = Aig_ManCreateMiter( pNew, pOld, 1 );
-    pMiter = Dar_ManRwsat( pAigTemp = pMiter, 1, 0 );
-    Aig_ManStop( pAigTemp );
+//    pMiter = Dar_ManRwsat( pAigTemp = pMiter, 1, 0 );
+//    Aig_ManStop( pAigTemp );
     RetValue = Fra_FraigMiterStatus( pMiter );
     if ( RetValue == -1 )
     {
         pAigTemp = Fra_FraigEquivence( pMiter, 1000000, 1 );
         RetValue = Fra_FraigMiterStatus( pAigTemp );
         Aig_ManStop( pAigTemp );
+//        RetValue = Fra_FraigSat( pMiter, 1000000, 0, 0 );
     }
     assert( RetValue != -1 );
     Aig_ManStop( pMiter );
@@ -495,9 +495,8 @@ void Saig_ManagerFree( Saig_IntMan_t * p )
   SeeAlso     []
 
 ***********************************************************************/
-int Saig_Interpolate( Aig_Man_t * pAig, int nConfLimit, int fVerbose, int * pDepth )
+int Saig_Interpolate( Aig_Man_t * pAig, int nConfLimit, int fRewrite, int fTransLoop, int fVerbose, int * pDepth )
 {
-    int fUseTransRel = 0;
     Saig_IntMan_t * p;
     Aig_Man_t * pAigTemp;
     int s, i, RetValue, Status, clk, clk2, clkTotal = clock();
@@ -516,10 +515,12 @@ int Saig_Interpolate( Aig_Man_t * pAig, int nConfLimit, int fVerbose, int * pDep
     p->fVerbose = fVerbose;
     // can perform SAT sweeping and/or rewriting of this AIG...
     p->pAig = pAig;      
-    if ( fUseTransRel )
+    if ( fTransLoop )
         p->pAigTrans = Saig_ManTransformed( pAig );
     else
         p->pAigTrans = Saig_ManDuplicated( pAig );
+//    p->pAigTrans = Dar_ManRwsat( pAigTemp = p->pAigTrans, 1, 0 );
+//    Aig_ManStop( pAigTemp );
     // derive CNF for the transformed AIG
 clk = clock();
     p->pCnfAig = Cnf_Derive( p->pAigTrans, Aig_ManRegNum(p->pAigTrans) ); 
@@ -527,7 +528,7 @@ p->timeCnf += clock() - clk;
     if ( fVerbose )
     { 
         printf( "AIG: PI/PO/Reg = %d/%d/%d. And = %d. Lev = %d.  CNF: Var/Cla = %d/%d.\n",
-            Aig_ManPiNum(pAig), Aig_ManPoNum(pAig), Aig_ManRegNum(pAig), 
+            Saig_ManPiNum(pAig), Saig_ManPoNum(pAig), Saig_ManRegNum(pAig), 
             Aig_ManAndNum(pAig), Aig_ManLevelNum(pAig),
             p->pCnfAig->nVars, p->pCnfAig->nClauses );
     }
@@ -545,10 +546,13 @@ p->timeCnf += clock() - clk;
         // timeframes
         p->pFrames = Saig_ManFramesInter( pAig, p->nFrames );
 clk = clock();
-//        p->pFrames = Dar_ManRwsat( pAigTemp = p->pFrames, 1, 0 );
-//        Aig_ManStop( pAigTemp );
+        if ( fRewrite )
+        {
+            p->pFrames = Dar_ManRwsat( pAigTemp = p->pFrames, 1, 0 );
+            Aig_ManStop( pAigTemp );
 //        p->pFrames = Fra_FraigEquivence( pAigTemp = p->pFrames, 100, 0 );
 //        Aig_ManStop( pAigTemp );
+        }
 p->timeRwr += clock() - clk;
         // can also do SAT sweeping on the timeframes...
 clk = clock();
@@ -569,7 +573,7 @@ p->timeCnf += clock() - clk;
             RetValue = Saig_PerformOneStep( p );
             if ( fVerbose )
             {
-                printf( "   I = %2d. Bmc =%3d. IntAnd =%6d. IntLev =%4d. Conf =%6d.  ", 
+                printf( "   I = %2d. Bmc =%3d. IntAnd =%6d. IntLev =%5d. Conf =%6d.  ", 
                     i+1, i + 1 + p->nFrames, Aig_ManNodeNum(p->pInter), Aig_ManLevelNum(p->pInter), p->nConfCur );
                 PRT( "Time", clock() - clk );
                 if ( Aig_ManNodeNum(p->pInter) == 0 )
@@ -623,7 +627,7 @@ p->timeEqu += clock() - clk;
                 return 1;
             }
             // save interpolant and convert it into CNF
-            if ( fUseTransRel )
+            if ( fTransLoop )
             {
                 Aig_ManStop( p->pInter );
                 p->pInter = p->pInterNew; 

src/base/abci/abc.c

@@ -54,6 +54,7 @@ static int Abc_CommandPrintGates     ( Abc_Frame_t * pAbc, int argc, char ** arg
 static int Abc_CommandPrintSharing   ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandPrintXCut      ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandPrintDsd       ( Abc_Frame_t * pAbc, int argc, char ** argv );
+static int Abc_CommandPrintCone      ( Abc_Frame_t * pAbc, int argc, char ** argv );
 
 static int Abc_CommandShow           ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandShowBdd        ( Abc_Frame_t * pAbc, int argc, char ** argv );
@@ -307,6 +308,7 @@ void Abc_Init( Abc_Frame_t * pAbc )
     Cmd_CommandAdd( pAbc, "Printing",     "print_sharing", Abc_CommandPrintSharing,     0 );
     Cmd_CommandAdd( pAbc, "Printing",     "print_xcut",    Abc_CommandPrintXCut,        0 );
     Cmd_CommandAdd( pAbc, "Printing",     "print_dsd",     Abc_CommandPrintDsd,         0 );
+    Cmd_CommandAdd( pAbc, "Printing",     "print_cone",    Abc_CommandPrintCone,        0 );
 
     Cmd_CommandAdd( pAbc, "Printing",     "show",          Abc_CommandShow,             0 );
     Cmd_CommandAdd( pAbc, "Printing",     "show_bdd",      Abc_CommandShowBdd,          0 );
@@ -1831,6 +1833,67 @@ usage:
     return 1;
 }
 
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Abc_CommandPrintCone( Abc_Frame_t * pAbc, int argc, char ** argv )
+{
+    FILE * pOut, * pErr;
+    Abc_Ntk_t * pNtk;
+    int c;
+    int fUseLibrary;
+
+    extern int Abc_NtkDarPrintCone( Abc_Ntk_t * pNtk );
+
+    pNtk = Abc_FrameReadNtk(pAbc);
+    pOut = Abc_FrameReadOut(pAbc);
+    pErr = Abc_FrameReadErr(pAbc);
+
+    // set defaults
+    fUseLibrary = 1;
+    Extra_UtilGetoptReset();
+    while ( ( c = Extra_UtilGetopt( argc, argv, "lh" ) ) != EOF )
+    {
+        switch ( c )
+        {
+        case 'l':
+            fUseLibrary ^= 1;
+            break;
+        case 'h':
+            goto usage;
+        default:
+            goto usage;
+        }
+    }
+    if ( pNtk == NULL )
+    {
+        fprintf( pErr, "Empty network.\n" );
+        return 1;
+    }
+    if ( Abc_NtkLatchNum(pNtk) == 0 )
+    {
+        fprintf( pErr, "The network is combinational.\n" );
+        return 1;
+    }
+    Abc_NtkDarPrintCone( pNtk );
+    return 0;
+
+usage:
+    fprintf( pErr, "usage: print_cone [-h]\n" );
+    fprintf( pErr, "\t        prints cones of influence info for each primary output\n" );
+//    fprintf( pErr, "\t-l    : used library gate names (if mapped) [default = %s]\n", fUseLibrary? "yes": "no" );
+    fprintf( pErr, "\t-h    : print the command usage\n");
+    return 1;
+}
+
 
 /**Function*************************************************************
 
@@ -14561,22 +14624,23 @@ int Abc_CommandBmc( Abc_Frame_t * pAbc, int argc, char ** argv )
     int nFrames;
     int nBTLimit;
     int fRewrite;
+    int fNewAlgo;
     int fVerbose;
 
-//    extern void Abc_NtkBmc( Abc_Ntk_t * pNtk, int nFrames, int fInit, int fVerbose );
-    extern int Abc_NtkDarBmc( Abc_Ntk_t * pNtk, int nFrames, int nBTLimit, int fRewrite, int fVerbose );
+    extern int Abc_NtkDarBmc( Abc_Ntk_t * pNtk, int nFrames, int nBTLimit, int fRewrite, int fNewAlgo, int fVerbose );
 
     pNtk = Abc_FrameReadNtk(pAbc);
     pOut = Abc_FrameReadOut(pAbc);
     pErr = Abc_FrameReadErr(pAbc);
 
     // set defaults
-    nFrames  = 5;
-    nBTLimit = 1000000;
+    nFrames  = 10;
+    nBTLimit = 10000;
     fRewrite = 0;
+    fNewAlgo = 1;
     fVerbose = 0;
     Extra_UtilGetoptReset();
-    while ( ( c = Extra_UtilGetopt( argc, argv, "FCrvh" ) ) != EOF )
+    while ( ( c = Extra_UtilGetopt( argc, argv, "FCravh" ) ) != EOF )
     {
         switch ( c )
         {
@@ -14605,6 +14669,9 @@ int Abc_CommandBmc( Abc_Frame_t * pAbc, int argc, char ** argv )
         case 'r':
             fRewrite ^= 1;
             break;
+        case 'a':
+            fNewAlgo ^= 1;
+            break;
         case 'v':
             fVerbose ^= 1;
             break;
@@ -14629,15 +14696,16 @@ int Abc_CommandBmc( Abc_Frame_t * pAbc, int argc, char ** argv )
         fprintf( stdout, "Does not work for combinational networks.\n" );
         return 0;
     }
-    Abc_NtkDarBmc( pNtk, nFrames, nBTLimit, fRewrite, fVerbose );
+    Abc_NtkDarBmc( pNtk, nFrames, nBTLimit, fRewrite, fNewAlgo, fVerbose );
     return 0;
 
 usage:
-    fprintf( pErr, "usage: bmc [-F num] [-C num] [-rvh]\n" );
+    fprintf( pErr, "usage: bmc [-F num] [-C num] [-ravh]\n" );
     fprintf( pErr, "\t         perform bounded model checking\n" );
     fprintf( pErr, "\t-F num : the number of time frames [default = %d]\n", nFrames );
     fprintf( pErr, "\t-C num : the max number of conflicts at a node [default = %d]\n", nBTLimit );
     fprintf( pErr, "\t-r     : toggle the use of rewriting [default = %s]\n", fRewrite? "yes": "no" );
+    fprintf( pErr, "\t-a     : toggle SAT sweeping and SAT solving [default = %s]\n", fNewAlgo? "SAT solving": "SAT sweeping" );
     fprintf( pErr, "\t-v     : toggle verbose output [default = %s]\n", fVerbose? "yes": "no" );
     fprintf( pErr, "\t-h     : print the command usage\n");
     return 1;
@@ -14661,9 +14729,10 @@ int Abc_CommandBmcInter( Abc_Frame_t * pAbc, int argc, char ** argv )
     int c;
     int nBTLimit;
     int fRewrite;
+    int fTransLoop;
     int fVerbose;
 
-    extern int Abc_NtkDarBmcInter( Abc_Ntk_t * pNtk, int nConfLimit, int fVerbose );
+    extern int Abc_NtkDarBmcInter( Abc_Ntk_t * pNtk, int nConfLimit, int fRewrite, int fTransLoop, int fVerbose );
 
     pNtk = Abc_FrameReadNtk(pAbc);
     pOut = Abc_FrameReadOut(pAbc);
@@ -14672,9 +14741,10 @@ int Abc_CommandBmcInter( Abc_Frame_t * pAbc, int argc, char ** argv )
     // set defaults
     nBTLimit   = 20000;
     fRewrite   = 0;
+    fTransLoop = 1;
     fVerbose   = 1;
     Extra_UtilGetoptReset();
-    while ( ( c = Extra_UtilGetopt( argc, argv, "Crvh" ) ) != EOF )
+    while ( ( c = Extra_UtilGetopt( argc, argv, "Crtvh" ) ) != EOF )
     {
         switch ( c )
         {
@@ -14692,6 +14762,9 @@ int Abc_CommandBmcInter( Abc_Frame_t * pAbc, int argc, char ** argv )
         case 'r':
             fRewrite ^= 1;
             break;
+        case 't':
+            fTransLoop ^= 1;
+            break;
         case 'v':
             fVerbose ^= 1;
             break;
@@ -14721,14 +14794,15 @@ int Abc_CommandBmcInter( Abc_Frame_t * pAbc, int argc, char ** argv )
         fprintf( stdout, "Currently only works for single-output miters (run \"orpos\").\n" );
         return 0;
     }
-    Abc_NtkDarBmcInter( pNtk, nBTLimit, fVerbose );
+    Abc_NtkDarBmcInter( pNtk, nBTLimit, fRewrite, fTransLoop, fVerbose );
     return 0;
 
 usage:
-    fprintf( pErr, "usage: int [-C num] [-vh]\n" );
+    fprintf( pErr, "usage: int [-C num] [-rtvh]\n" );
     fprintf( pErr, "\t         uses interpolation to prove the property\n" );
     fprintf( pErr, "\t-C num : the limit on conflicts for one SAT run [default = %d]\n", nBTLimit );
-//    fprintf( pErr, "\t-r     : toggle the use of rewriting [default = %s]\n", fRewrite? "yes": "no" );
+    fprintf( pErr, "\t-r     : toggle the use of rewriting [default = %s]\n", fRewrite? "yes": "no" );
+    fprintf( pErr, "\t-t     : toggle adding transition into the init state [default = %s]\n", fTransLoop? "yes": "no" );
     fprintf( pErr, "\t-v     : toggle verbose output [default = %s]\n", fVerbose? "yes": "no" );
     fprintf( pErr, "\t-h     : print the command usage\n");
     return 1;

src/base/abci/abcBalance.c

@@ -346,7 +346,7 @@ int Abc_NodeBalanceCone_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst,
         return 0;
     }
     // if the new node is complemented or a PI, another gate begins
-    if ( !fFirst && (Abc_ObjIsComplement(pNode) || !Abc_ObjIsNode(pNode) || !fDuplicate && !fSelective && (Abc_ObjFanoutNum(pNode) > 1)) )
+    if ( !fFirst && (Abc_ObjIsComplement(pNode) || !Abc_ObjIsNode(pNode) || (!fDuplicate && !fSelective && (Abc_ObjFanoutNum(pNode) > 1)) || Vec_PtrSize(vSuper) > 10000) )
     {
         Vec_PtrPush( vSuper, pNode );
         Abc_ObjRegular(pNode)->fMarkB = 1;

src/base/abci/abcDar.c

@@ -1202,10 +1202,10 @@ Abc_Ntk_t * Abc_NtkDarLcorr( Abc_Ntk_t * pNtk, int nFramesP, int nConfMax, int f
   SeeAlso     []
 
 ***********************************************************************/
-int Abc_NtkDarBmc( Abc_Ntk_t * pNtk, int nFrames, int nBTLimit, int fRewrite, int fVerbose )
+int Abc_NtkDarBmc( Abc_Ntk_t * pNtk, int nFrames, int nBTLimit, int fRewrite, int fNewAlgo, int fVerbose )
 {
     Aig_Man_t * pMan;
-    int clk = clock();
+    int RetValue, clk = clock();
     // derive the AIG manager
     pMan = Abc_NtkToDar( pNtk, 0, 1 );
     if ( pMan == NULL )
@@ -1214,7 +1214,25 @@ int Abc_NtkDarBmc( Abc_Ntk_t * pNtk, int nFrames, int nBTLimit, int fRewrite, in
         return -1;
     }
     assert( pMan->nRegs > 0 );
+    pMan->nTruePis = Aig_ManPiNum(pMan) - Aig_ManRegNum(pMan);
+    pMan->nTruePos = Aig_ManPoNum(pMan) - Aig_ManRegNum(pMan);
     // perform verification
+    if ( fNewAlgo )
+    {
+        int iFrame;
+        RetValue = Saig_ManBmcSimple( pMan, nFrames, nBTLimit, fRewrite, fVerbose, &iFrame );
+        if ( RetValue == 1 )
+            printf( "No output was asserted in %d frames. ", nFrames );
+        else if ( RetValue == -1 )
+            printf( "No output was asserted in %d frames. Reached conflict limit (%d). ", iFrame, nBTLimit );
+        else // if ( RetValue == 0 )
+        {
+            Fra_Cex_t * pCex = pNtk->pSeqModel;
+            printf( "Output %d was asserted in frame %d (use \"write_counter\" to dump the trace). ", pCex->iPo, pCex->iFrame );
+        }
+    }
+    else
+    {
         Fra_BmcPerformSimple( pMan, nFrames, nBTLimit, fRewrite, fVerbose );
         pNtk->pSeqModel = pMan->pSeqModel; pMan->pSeqModel = NULL;
         if ( pNtk->pSeqModel )
@@ -1223,7 +1241,8 @@ int Abc_NtkDarBmc( Abc_Ntk_t * pNtk, int nFrames, int nBTLimit, int fRewrite, in
             printf( "Output %d was asserted in frame %d (use \"write_counter\" to dump the trace). ", pCex->iPo, pCex->iFrame );
         }
         else
-        printf( "No output was asserted after BMC with %d frames. ", nFrames );
+            printf( "No output was asserted in %d frames. ", nFrames );
+    }
 PRT( "Time", clock() - clk );
     Aig_ManStop( pMan );
     return 1;
@@ -1240,7 +1259,7 @@ PRT( "Time", clock() - clk );
   SeeAlso     []
 
 ***********************************************************************/
-int Abc_NtkDarBmcInter( Abc_Ntk_t * pNtk, int nConfLimit, int fVerbose )
+int Abc_NtkDarBmcInter( Abc_Ntk_t * pNtk, int nConfLimit, int fRewrite, int fTransLoop, int fVerbose )
 {
     Aig_Man_t * pMan;
     int RetValue, Depth, clk = clock();
@@ -1254,7 +1273,7 @@ int Abc_NtkDarBmcInter( Abc_Ntk_t * pNtk, int nConfLimit, int fVerbose )
     assert( pMan->nRegs > 0 );
     pMan->nTruePis = Aig_ManPiNum(pMan) - Aig_ManRegNum(pMan);
     pMan->nTruePos = Aig_ManPoNum(pMan) - Aig_ManRegNum(pMan);
-    RetValue = Saig_Interpolate( pMan, nConfLimit, fVerbose, &Depth );
+    RetValue = Saig_Interpolate( pMan, nConfLimit, fRewrite, fTransLoop, fVerbose, &Depth );
     if ( RetValue == 1 )
         printf( "Property proved.  " );
     else if ( RetValue == 0 )
@@ -1892,7 +1911,7 @@ timeInt = 0;
 
 /**Function*************************************************************
 
-  Synopsis    [Interplates two networks.]
+  Synopsis    []
 
   Description []
                
@@ -1915,7 +1934,32 @@ void Abc_NtkPrintSccs( Abc_Ntk_t * pNtk, int fVerbose )
 
 /**Function*************************************************************
 
-  Synopsis    [Interplates two networks.]
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_NtkDarPrintCone( Abc_Ntk_t * pNtk )
+{
+    extern void Saig_ManPrintCones( Aig_Man_t * pAig );
+    Aig_Man_t * pMan;
+    pMan = Abc_NtkToDar( pNtk, 0, 1 );
+    if ( pMan == NULL )
+        return;
+    assert( Aig_ManRegNum(pMan) > 0 );
+    pMan->nTruePis = Aig_ManPiNum(pMan) - Aig_ManRegNum(pMan); 
+    pMan->nTruePos = Aig_ManPoNum(pMan) - Aig_ManRegNum(pMan); 
+    Saig_ManPrintCones( pMan );
+    Aig_ManStop( pMan );
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
 
   Description []
                
@@ -1947,7 +1991,6 @@ Abc_Ntk_t * Abc_NtkBalanceExor( Abc_Ntk_t * pNtk, int fUpdateLevel, int fVerbose
     return pNtkAig;
 }
 
-
 /**Function*************************************************************
 
   Synopsis    [Performs phase abstraction.]

src/sat/bsat/satUtil.c

@@ -170,7 +170,7 @@ int * Sat_SolverGetModel( sat_solver * p, int * pVars, int nVars )
 {
     int * pModel;
     int i;
-    pModel = ALLOC( int, nVars );
+    pModel = ALLOC( int, nVars+1 );
     for ( i = 0; i < nVars; i++ )
     {
         assert( pVars[i] >= 0 && pVars[i] < p->size );