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Diffstat (limited to 'src/aig/llb/llbPivot.c')
| -rw-r--r-- | src/aig/llb/llbPivot.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/src/aig/llb/llbPivot.c b/src/aig/llb/llbPivot.c new file mode 100644 index 00000000..6a6fb321 --- /dev/null +++ b/src/aig/llb/llbPivot.c @@ -0,0 +1,254 @@ +/**CFile**************************************************************** + + FileName [llbPivot.c] + + SystemName [ABC: Logic synthesis and verification system.] + + PackageName [BDD based reachability.] + + Synopsis [Determining pivot variables.] + + Author [Alan Mishchenko] + + Affiliation [UC Berkeley] + + Date [Ver. 1.0. Started - June 20, 2005.] + + Revision [$Id: llbPivot.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $] + +***********************************************************************/ + +#include "llbInt.h" + +ABC_NAMESPACE_IMPL_START + + +//////////////////////////////////////////////////////////////////////// +/// DECLARATIONS /// +//////////////////////////////////////////////////////////////////////// + +//////////////////////////////////////////////////////////////////////// +/// FUNCTION DEFINITIONS /// +//////////////////////////////////////////////////////////////////////// + +/**Function************************************************************* + + Synopsis [] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +int Llb_ManTracePaths_rec( Aig_Man_t * p, Aig_Obj_t * pObj, Aig_Obj_t * pPivot ) +{ + Aig_Obj_t * pFanout; + int k, iFan; + if ( Aig_ObjIsTravIdPrevious(p, pObj) ) + return 0; + if ( Aig_ObjIsTravIdCurrent(p, pObj) ) + return 1; + if ( Saig_ObjIsLi(p, pObj) ) + return 0; + if ( Saig_ObjIsPo(p, pObj) ) + return 0; + if ( pObj == pPivot ) + return 1; + assert( Aig_ObjIsCand(pObj) ); + Aig_ObjForEachFanout( p, pObj, pFanout, iFan, k ) + if ( !Llb_ManTracePaths_rec( p, pFanout, pPivot ) ) + { + Aig_ObjSetTravIdPrevious(p, pObj); + return 0; + } + Aig_ObjSetTravIdCurrent(p, pObj); + return 1; +} + +/**Function************************************************************* + + Synopsis [] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +int Llb_ManTracePaths( Aig_Man_t * p, Aig_Obj_t * pPivot ) +{ + Aig_Obj_t * pObj; + int i, Counter = 0; + Aig_ManIncrementTravId( p ); // prev = visited with path to LI (value 0) + Aig_ManIncrementTravId( p ); // cur = visited w/o path to LI (value 1) + Saig_ManForEachLo( p, pObj, i ) + Counter += Llb_ManTracePaths_rec( p, pObj, pPivot ); + return Counter; +} + +/**Function************************************************************* + + Synopsis [] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Llb_ManTestCuts( Aig_Man_t * p ) +{ + Aig_Obj_t * pObj; + int i, Count; + Aig_ManFanoutStart( p ); + Aig_ManForEachNode( p, pObj, i ) + { + if ( Aig_ObjRefs(pObj) <= 1 ) + continue; + Count = Llb_ManTracePaths( p, pObj ); + printf( "Obj =%5d. Lev =%3d. Fanout =%5d. Count = %3d.\n", + i, Aig_ObjLevel(pObj), Aig_ObjRefs(pObj), Count ); + } + Aig_ManFanoutStop( p ); +} + +/**Function************************************************************* + + Synopsis [] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Llb_ManLabelLiCones_rec( Aig_Man_t * p, Aig_Obj_t * pObj ) +{ + if ( pObj->fMarkB ) + return; + pObj->fMarkB = 1; + assert( Aig_ObjIsNode(pObj) ); + Llb_ManLabelLiCones_rec( p, Aig_ObjFanin0(pObj) ); + Llb_ManLabelLiCones_rec( p, Aig_ObjFanin1(pObj) ); +} + +/**Function************************************************************* + + Synopsis [Determine starting cut-points.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Llb_ManLabelLiCones( Aig_Man_t * p ) +{ + Aig_Obj_t * pObj; + int i; + // mark const and PIs + Aig_ManConst1(p)->fMarkB = 1; + Aig_ManForEachPi( p, pObj, i ) + pObj->fMarkB = 1; + // mark cones + Saig_ManForEachLi( p, pObj, i ) + Llb_ManLabelLiCones_rec( p, Aig_ObjFanin0(pObj) ); +} + +/**Function************************************************************* + + Synopsis [Determine starting cut-points.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Llb_ManMarkInternalPivots( Aig_Man_t * p ) +{ + Vec_Ptr_t * vMuxes; + Aig_Obj_t * pObj; + int i, Counter = 0; + + // remove refs due to MUXes + vMuxes = Aig_ManMuxesCollect( p ); + Aig_ManMuxesDeref( p, vMuxes ); + + // mark nodes feeding into LIs + Aig_ManCleanMarkB( p ); + Llb_ManLabelLiCones( p ); + + // mark internal nodes + Aig_ManFanoutStart( p ); + Aig_ManForEachNode( p, pObj, i ) + if ( pObj->fMarkB && pObj->nRefs > 1 ) + { + if ( Llb_ManTracePaths(p, pObj) > 0 ) + pObj->fMarkA = 1; + Counter++; + } + Aig_ManFanoutStop( p ); +// printf( "TracePath tried = %d.\n", Counter ); + + // mark nodes feeding into LIs + Aig_ManCleanMarkB( p ); + + // add refs due to MUXes + Aig_ManMuxesRef( p, vMuxes ); + Vec_PtrFree( vMuxes ); +} + +/**Function************************************************************* + + Synopsis [Determine starting cut-points.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +Vec_Int_t * Llb_ManMarkPivotNodes( Aig_Man_t * p, int fUseInternal ) +{ + Vec_Int_t * vVar2Obj; + Aig_Obj_t * pObj; + int i; + // mark inputs/outputs + Aig_ManForEachPi( p, pObj, i ) + pObj->fMarkA = 1; + Saig_ManForEachLi( p, pObj, i ) + pObj->fMarkA = 1; + + // mark internal pivot nodes + if ( fUseInternal ) + Llb_ManMarkInternalPivots( p ); + + // assign variable numbers + Aig_ManConst1(p)->fMarkA = 0; + vVar2Obj = Vec_IntAlloc( 100 ); + Aig_ManForEachPi( p, pObj, i ) + Vec_IntPush( vVar2Obj, Aig_ObjId(pObj) ); + Aig_ManForEachNode( p, pObj, i ) + if ( pObj->fMarkA ) + Vec_IntPush( vVar2Obj, Aig_ObjId(pObj) ); + Saig_ManForEachLi( p, pObj, i ) + Vec_IntPush( vVar2Obj, Aig_ObjId(pObj) ); + return vVar2Obj; +} + +//////////////////////////////////////////////////////////////////////// +/// END OF FILE /// +//////////////////////////////////////////////////////////////////////// + + +ABC_NAMESPACE_IMPL_END + |