/**CFile**************************************************************** FileName [abcDsdRes.c] SystemName [ABC: Logic synthesis and verification system.] PackageName [Network and node package.] Synopsis [] Author [Alan Mishchenko] Affiliation [UC Berkeley] Date [Ver. 1.0. Started - June 20, 2005.] Revision [$Id: abcDsdRes.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $] ***********************************************************************/ #include "abc.h" //////////////////////////////////////////////////////////////////////// /// DECLARATIONS /// //////////////////////////////////////////////////////////////////////// #define LUT_SIZE_MAX 16 // the largest size of the function #define LUT_CUTS_MAX 128 // the largest number of cuts considered typedef struct Lut_Man_t_ Lut_Man_t; typedef struct Lut_Cut_t_ Lut_Cut_t; struct Lut_Cut_t_ { unsigned nLeaves : 6; // (L) the number of leaves unsigned nNodes : 6; // (M) the number of nodes unsigned nNodesMarked : 6; // (Q) nodes outside of MFFC unsigned nNodesMax : 6; // the max number of nodes unsigned nLeavesMax : 6; // the max number of leaves unsigned fHasDsd : 1; // set to 1 if the cut has structural DSD (and so cannot be used) unsigned fMark : 1; // multipurpose mark // unsigned uSign[2]; // the signature float Weight; // the weight of the cut: (M - Q)/N(V) (the larger the better) int Gain; // the gain achieved using this cut int pLeaves[LUT_SIZE_MAX]; // the leaves of the cut int pNodes[LUT_SIZE_MAX]; // the nodes of the cut }; struct Lut_Man_t_ { // parameters Lut_Par_t * pPars; // the set of parameters // current representation Abc_Ntk_t * pNtk; // the network Abc_Obj_t * pObj; // the node to resynthesize // cut representation int nMffc; // the size of MFFC of the node int nCuts; // the total number of cuts int nCutsMax; // the largest possible number of cuts int nEvals; // the number of good cuts Lut_Cut_t pCuts[LUT_CUTS_MAX]; // the storage for cuts int pEvals[LUT_CUTS_MAX]; // the good cuts // temporary variables int pRefs[LUT_SIZE_MAX]; // fanin reference counters int pCands[LUT_SIZE_MAX]; // internal nodes pointing only to the leaves // truth table representation Vec_Ptr_t * vTtElems; // elementary truth tables Vec_Ptr_t * vTtNodes; // storage for temporary truth tables of the nodes // statistics int nCutsTotal; int nGainTotal; // rutime int timeCuts; int timeTruth; int timeEval; int timeOther; int timeTotal; }; #define Abc_LutCutForEachLeaf( pNtk, pCut, pObj, i ) \ for ( i = 0; (i < (int)(pCut)->nLeaves) && (((pObj) = Abc_NtkObj(pNtk, (pCut)->pLeaves[i])), 1); i++ ) #define Abc_LutCutForEachNode( pNtk, pCut, pObj, i ) \ for ( i = 0; (i < (int)(pCut)->nNodes) && (((pObj) = Abc_NtkObj(pNtk, (pCut)->pNodes[i])), 1); i++ ) #define Abc_LutCutForEachNodeReverse( pNtk, pCut, pObj, i ) \ for ( i = (int)(pCut)->nNodes - 1; (i >= 0) && (((pObj) = Abc_NtkObj(pNtk, (pCut)->pNodes[i])), 1); i-- ) //////////////////////////////////////////////////////////////////////// /// FUNCTION DEFINITIONS /// //////////////////////////////////////////////////////////////////////// /**Function************************************************************* Synopsis [] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ Lut_Man_t * Abc_LutManStart( Lut_Par_t * pPars ) { Lut_Man_t * p; int i; assert( pPars->nLutsMax <= 16 ); assert( pPars->nVarsMax > 0 ); p = ALLOC( Lut_Man_t, 1 ); memset( p, 0, sizeof(Lut_Man_t) ); p->pPars = pPars; p->nCutsMax = LUT_CUTS_MAX; for ( i = 0; i < p->nCuts; i++ ) p->pCuts[i].nLeavesMax = p->pCuts[i].nNodesMax = LUT_SIZE_MAX; p->vTtElems = Vec_PtrAllocTruthTables( pPars->nVarsMax ); p->vTtNodes = Vec_PtrAllocSimInfo( 256, Abc_TruthWordNum(pPars->nVarsMax) ); return p; } /**Function************************************************************* Synopsis [] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ void Abc_LutManStop( Lut_Man_t * p ) { Vec_PtrFree( p->vTtElems ); Vec_PtrFree( p->vTtNodes ); free( p ); } /**Function************************************************************* Synopsis [Returns 1 if the cut has structural DSD.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ int Abc_LutNodeCutsCheckDsd( Lut_Man_t * p, Lut_Cut_t * pCut ) { Abc_Obj_t * pObj, * pFanin; int i, k, nCands, fLeavesOnly, RetValue; assert( pCut->nLeaves > 0 ); // clear ref counters memset( p->pRefs, 0, sizeof(int) * pCut->nLeaves ); // mark cut leaves Abc_LutCutForEachLeaf( p->pNtk, pCut, pObj, i ) { assert( pObj->fMarkA == 0 ); pObj->fMarkA = 1; pObj->pCopy = (void *)i; } // ref leaves pointed from the internal nodes nCands = 0; Abc_LutCutForEachNode( p->pNtk, pCut, pObj, i ) { fLeavesOnly = 1; Abc_ObjForEachFanin( pObj, pFanin, k ) if ( pFanin->fMarkA ) p->pRefs[(int)pFanin->pCopy]++; else fLeavesOnly = 0; if ( fLeavesOnly ) p->pCands[nCands++] = pObj->Id; } // look at the nodes that only point to the leaves RetValue = 0; for ( i = 0; i < nCands; i++ ) { pObj = Abc_NtkObj( p->pNtk, p->pCands[i] ); Abc_ObjForEachFanin( pObj, pFanin, k ) { assert( pFanin->fMarkA == 1 ); if ( p->pRefs[(int)pFanin->pCopy] > 1 ) break; } if ( k == Abc_ObjFaninNum(pObj) ) { RetValue = 1; break; } } // unmark cut leaves Abc_LutCutForEachLeaf( p->pNtk, pCut, pObj, i ) pObj->fMarkA = 0; return RetValue; } /**Function************************************************************* Synopsis [Returns 1 if pDom is contained in pCut.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ static inline int Abc_LutNodeCutsOneDominance( Lut_Cut_t * pDom, Lut_Cut_t * pCut ) { int i, k; for ( i = 0; i < (int)pDom->nLeaves; i++ ) { for ( k = 0; k < (int)pCut->nLeaves; k++ ) if ( pDom->pLeaves[i] == pCut->pLeaves[k] ) break; if ( k == (int)pCut->nLeaves ) // node i in pDom is not contained in pCut return 0; } // every node in pDom is contained in pCut return 1; } /**Function************************************************************* Synopsis [Check if the cut exists.] Description [Returns 1 if the cut exists.] SideEffects [] SeeAlso [] ***********************************************************************/ int Abc_LutNodeCutsOneFilter( Lut_Cut_t * pCuts, int nCuts, Lut_Cut_t * pCutNew ) { Lut_Cut_t * pCut; int i, k; // assert( pCutNew->uHash ); // try to find the cut for ( i = 0; i < nCuts; i++ ) { pCut = pCuts + i; if ( pCut->nLeaves == 0 ) continue; if ( pCut->nLeaves == pCutNew->nLeaves ) { // if ( pCut->uHash[0] == pCutNew->uHash[0] && pCut->uHash[1] == pCutNew->uHash[1] ) { for ( k = 0; k < (int)pCutNew->nLeaves; k++ ) if ( pCut->pLeaves[k] != pCutNew->pLeaves[k] ) break; if ( k == (int)pCutNew->nLeaves ) return 1; } continue; } if ( pCut->nLeaves < pCutNew->nLeaves ) { // skip the non-contained cuts // if ( (pCut->uHash[0] & pCutNew->uHash[0]) != pCut->uHash[0] ) // continue; // if ( (pCut->uHash[1] & pCutNew->uHash[1]) != pCut->uHash[1] ) // continue; // check containment seriously if ( Abc_LutNodeCutsOneDominance( pCut, pCutNew ) ) return 1; continue; } // check potential containment of other cut // skip the non-contained cuts // if ( (pCut->uHash[0] & pCutNew->uHash[0]) != pCutNew->uHash[0] ) // continue; // if ( (pCut->uHash[1] & pCutNew->uHash[1]) != pCutNew->uHash[1] ) // continue; // check containment seriously if ( Abc_LutNodeCutsOneDominance( pCutNew, pCut ) ) pCut->nLeaves = 0; // removed } return 0; } /**Function************************************************************* Synopsis [Prints the given cut.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ void Abc_LutNodePrintCut( Lut_Man_t * p, Lut_Cut_t * pCut ) { Abc_Obj_t * pObj; int i; printf( "LEAVES:\n" ); Abc_LutCutForEachLeaf( p->pNtk, pCut, pObj, i ) { Abc_ObjPrint( stdout, pObj ); } printf( "NODES:\n" ); Abc_LutCutForEachNode( p->pNtk, pCut, pObj, i ) { Abc_ObjPrint( stdout, pObj ); assert( Abc_ObjIsNode(pObj) ); } printf( "\n" ); } /**Function************************************************************* Synopsis [Computes the set of all cuts.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ void Abc_LutNodeCutsOne( Lut_Man_t * p, Lut_Cut_t * pCut, int Node ) { Lut_Cut_t * pCutNew; Abc_Obj_t * pObj, * pFanin; int i, k, j; // check if the cut can stand adding one more internal node if ( pCut->nNodes == LUT_SIZE_MAX ) return; // if the node is a PI, quit pObj = Abc_NtkObj( p->pNtk, Node ); if ( Abc_ObjIsCi(pObj) ) return; assert( Abc_ObjIsNode(pObj) ); assert( Abc_ObjFaninNum(pObj) <= p->pPars->nLutSize ); // if the node is not in the MFFC, check the limit if ( !Abc_NodeIsTravIdCurrent(pObj) ) { if ( (int)pCut->nNodesMarked == p->pPars->nLutsOver ) return; assert( (int)pCut->nNodesMarked < p->pPars->nLutsOver ); } // initialize the set of leaves to the nodes in the cut assert( p->nCuts < LUT_CUTS_MAX ); pCutNew = p->pCuts + p->nCuts; /* if ( p->pObj->Id == 31 && Node == 38 && pCut->pNodes[0] == 31 && pCut->pNodes[1] == 34 && pCut->pNodes[2] == 35 )//p->nCuts == 48 ) { int x = 0; printf( "Start:\n" ); Abc_LutNodePrintCut( p, pCut ); } */ pCutNew->nLeaves = 0; for ( i = 0; i < (int)pCut->nLeaves; i++ ) if ( pCut->pLeaves[i] != Node ) pCutNew->pLeaves[pCutNew->nLeaves++] = pCut->pLeaves[i]; // add new nodes Abc_ObjForEachFanin( pObj, pFanin, i ) { // find the place where this node belongs for ( k = 0; k < (int)pCutNew->nLeaves; k++ ) if ( pCutNew->pLeaves[k] >= pFanin->Id ) break; if ( k < (int)pCutNew->nLeaves && pCutNew->pLeaves[k] == pFanin->Id ) continue; // check if there is room if ( (int)pCutNew->nLeaves == p->pPars->nVarsMax ) return; // move all the nodes for ( j = pCutNew->nLeaves; j > k; j-- ) pCutNew->pLeaves[j] = pCutNew->pLeaves[j-1]; pCutNew->pLeaves[k] = pFanin->Id; pCutNew->nLeaves++; assert( pCutNew->nLeaves <= LUT_SIZE_MAX ); } for ( k = 0; k < (int)pCutNew->nLeaves - 1; k++ ) assert( pCutNew->pLeaves[k] < pCutNew->pLeaves[k+1] ); // skip the contained cuts if ( Abc_LutNodeCutsOneFilter( p->pCuts, p->nCuts, pCutNew ) ) return; // update the set of internal nodes assert( pCut->nNodes < LUT_SIZE_MAX ); memcpy( pCutNew->pNodes, pCut->pNodes, pCut->nNodes * sizeof(int) ); pCutNew->nNodes = pCut->nNodes; pCutNew->pNodes[ pCutNew->nNodes++ ] = Node; // add the marked node pCutNew->nNodesMarked = pCut->nNodesMarked + !Abc_NodeIsTravIdCurrent(pObj); /* if ( p->pObj->Id == 31 && Node == 38 )//p->nCuts == 48 ) { int x = 0; printf( "Finish:\n" ); Abc_LutNodePrintCut( p, pCutNew ); } */ // add the cut to storage assert( p->nCuts < LUT_CUTS_MAX ); p->nCuts++; assert( pCut->nNodes <= p->nMffc + pCutNew->nNodesMarked ); } /**Function************************************************************* Synopsis [Computes the set of all cuts.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ int Abc_LutNodeCuts( Lut_Man_t * p ) { Abc_Obj_t * pFanin; Lut_Cut_t * pCut, * pCut2; int i, k, Temp, nMffc, fChanges; // mark the MFFC of the node with the current trav ID nMffc = p->nMffc = Abc_NodeMffcLabel( p->pObj ); assert( nMffc > 0 ); if ( nMffc == 1 ) return 0; // initialize the first cut pCut = p->pCuts; p->nCuts = 1; // assign internal nodes pCut->nNodes = 1; pCut->pNodes[0] = p->pObj->Id; pCut->nNodesMarked = 0; // assign the leaves pCut->nLeaves = Abc_ObjFaninNum( p->pObj ); Abc_ObjForEachFanin( p->pObj, pFanin, i ) pCut->pLeaves[i] = pFanin->Id; // sort the leaves do { fChanges = 0; for ( i = 0; i < (int)pCut->nLeaves - 1; i++ ) { if ( pCut->pLeaves[i] <= pCut->pLeaves[i+1] ) continue; Temp = pCut->pLeaves[i]; pCut->pLeaves[i] = pCut->pLeaves[i+1]; pCut->pLeaves[i+1] = Temp; fChanges = 1; } } while ( fChanges ); // perform the cut computation for ( i = 0; i < p->nCuts; i++ ) { pCut = p->pCuts + i; if ( pCut->nLeaves == 0 ) continue; // try to expand the fanins of this cut for ( k = 0; k < (int)pCut->nLeaves; k++ ) { Abc_LutNodeCutsOne( p, pCut, pCut->pLeaves[k] ); if ( p->nCuts == LUT_CUTS_MAX ) break; } if ( p->nCuts == LUT_CUTS_MAX ) break; } // compress the cuts by removing empty ones, decomposable ones, and those with negative Weight p->nEvals = 0; for ( i = 0; i < p->nCuts; i++ ) { pCut = p->pCuts + i; if ( pCut->nLeaves == 0 ) continue; pCut->Weight = (float)1.0 * (pCut->nNodes - pCut->nNodesMarked) / p->pPars->nLutsMax; if ( pCut->Weight <= 1.0 ) continue; pCut->fHasDsd = Abc_LutNodeCutsCheckDsd( p, pCut ); if ( pCut->fHasDsd ) continue; p->pEvals[p->nEvals++] = i; } if ( p->nEvals == 0 ) return 0; // sort the cuts by Weight do { fChanges = 0; for ( i = 0; i < p->nEvals - 1; i++ ) { pCut = p->pCuts + p->pEvals[i]; pCut2 = p->pCuts + p->pEvals[i+1]; if ( pCut->Weight >= pCut2->Weight ) continue; Temp = p->pEvals[i]; p->pEvals[i] = p->pEvals[i+1]; p->pEvals[i+1] = Temp; fChanges = 1; } } while ( fChanges ); return 1; } /**Function************************************************************* Synopsis [Computes the truth able of one cut.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ unsigned * Abc_LutCutTruth_rec( Hop_Man_t * pMan, Hop_Obj_t * pObj, int nVars, Vec_Ptr_t * vTtNodes, int * iCount ) { unsigned * pTruth, * pTruth0, * pTruth1; assert( !Hop_IsComplement(pObj) ); if ( pObj->pData ) { assert( ((unsigned)pObj->pData) & 0xffff0000 ); return pObj->pData; } // get the plan for a new truth table pTruth = Vec_PtrEntry( vTtNodes, (*iCount)++ ); if ( Hop_ObjIsConst1(pObj) ) Extra_TruthFill( pTruth, nVars ); else { assert( Hop_ObjIsAnd(pObj) ); // compute the truth tables of the fanins pTruth0 = Abc_LutCutTruth_rec( pMan, Hop_ObjFanin0(pObj), nVars, vTtNodes, iCount ); pTruth1 = Abc_LutCutTruth_rec( pMan, Hop_ObjFanin1(pObj), nVars, vTtNodes, iCount ); // creat the truth table of the node Extra_TruthAndPhase( pTruth, pTruth0, pTruth1, nVars, Hop_ObjFaninC0(pObj), Hop_ObjFaninC1(pObj) ); } pObj->pData = pTruth; return pTruth; } /**Function************************************************************* Synopsis [Computes the truth able of one cut.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ unsigned * Abc_LutCutTruth( Lut_Man_t * p, Lut_Cut_t * pCut ) { Hop_Man_t * pManHop = p->pNtk->pManFunc; Hop_Obj_t * pObjHop; Abc_Obj_t * pObj, * pFanin; unsigned * pTruth; int i, k, iCount = 0; // Abc_LutNodePrintCut( p, pCut ); // initialize the leaves Abc_LutCutForEachLeaf( p->pNtk, pCut, pObj, i ) pObj->pCopy = Vec_PtrEntry( p->vTtElems, i ); // construct truth table in the topological order Abc_LutCutForEachNodeReverse( p->pNtk, pCut, pObj, i ) { // get the local AIG pObjHop = Hop_Regular(pObj->pData); // clean the data field of the nodes in the AIG subgraph Hop_ObjCleanData_rec( pObjHop ); // set the initial truth tables at the fanins Abc_ObjForEachFanin( pObj, pFanin, k ) { assert( ((unsigned)pFanin->pCopy) & 0xffff0000 ); Hop_ManPi( pManHop, k )->pData = pFanin->pCopy; } // compute the truth table of internal nodes pTruth = Abc_LutCutTruth_rec( pManHop, pObjHop, pCut->nLeaves, p->vTtNodes, &iCount ); if ( Hop_IsComplement(pObj->pData) ) Extra_TruthNot( pTruth, pTruth, pCut->nLeaves ); // set the truth table at the node pObj->pCopy = (Abc_Obj_t *)pTruth; } return pTruth; } /**Function************************************************************* Synopsis [Implements the given DSD network.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ int Abc_LutCutUpdate( Lut_Man_t * p, Lut_Cut_t * pCut, void * pDsd ) { return 1; } /**Function************************************************************* Synopsis [Performs resynthesis for one node.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ int Abc_LutResynthesizeNode( Lut_Man_t * p ) { extern void Kit_DsdTest( unsigned * pTruth, int nVars ); extern int Kit_DsdEval( unsigned * pTruth, int nVars, int nLutSize ); Lut_Cut_t * pCut; unsigned * pTruth; void * pDsd = NULL; int i, Result, GainBest, Gain; int clk; // compute the cuts clk = clock(); if ( !Abc_LutNodeCuts( p ) ) { p->timeCuts += clock() - clk; return 0; } p->timeCuts += clock() - clk; if ( p->pPars->fVeryVerbose ) printf( "Node %5d : Mffc size = %5d. Cuts = %5d.\n", p->pObj->Id, p->nMffc, p->nEvals ); // try the good cuts p->nCutsTotal += p->nEvals; GainBest = 0; for ( i = 0; i < p->nEvals; i++ ) { // get the cut pCut = p->pCuts + p->pEvals[i]; // compute the truth table clk = clock(); pTruth = Abc_LutCutTruth( p, pCut ); p->timeTruth += clock() - clk; // evaluate the result of decomposition clk = clock(); // Kit_DsdTest( pTruth, pCut->nLeaves ); Result = Kit_DsdEval( pTruth, pCut->nLeaves, 3 ); p->timeEval += clock() - clk; // calculate the gain Gain = Result < 0 ? 0 : pCut->nNodes - pCut->nNodesMarked - Result; if ( GainBest < Gain ) GainBest = Gain; if ( p->pPars->fVeryVerbose ) { printf( " Cut %2d : Lvs = %2d. Supp = %2d. Vol = %2d. Q = %d. Weight = %4.2f. New = %2d. Gain = %2d.\n", i, pCut->nLeaves, Extra_TruthSupportSize(pTruth, pCut->nLeaves), pCut->nNodes, pCut->nNodesMarked, pCut->Weight, Result, Gain ); // for ( k = 0; k < pCut->nNodes; k++ ) // printf( "%d(%d) ", pCut->pNodes[k], Abc_NodeIsTravIdCurrent( Abc_NtkObj(p->pNtk, pCut->pNodes[k]) ) ); // printf( "\n" ); } // pTruth = NULL; //Extra_PrintHexadecimal( stdout, pTruth, pCut->nLeaves ); printf( "\n" ); // if it is not DSD decomposable, return if ( pDsd == NULL ) continue; // update the network Abc_LutCutUpdate( p, pCut, pDsd ); } p->nGainTotal += GainBest; return 1; } /**Function************************************************************* Synopsis [Performs resynthesis for one network.] Description [] SideEffects [] SeeAlso [] ***********************************************************************/ int Abc_LutResynthesize( Abc_Ntk_t * pNtk, Lut_Par_t * pPars ) { Lut_Man_t * p; Abc_Obj_t * pObj; int i, clk = clock(); assert( Abc_NtkIsLogic(pNtk) ); // convert logic to AIGs Abc_NtkToAig( pNtk ); // compute the levels Abc_NtkLevel( pNtk ); // get the number of inputs pPars->nLutSize = Abc_NtkGetFaninMax( pNtk ); pPars->nVarsMax = pPars->nLutsMax * (pPars->nLutSize - 1) + 1; // V = N * (K-1) + 1 printf( "Resynthesis for %d %d-LUTs with %d non-MFFC LUTs, %d crossbars, and %d-input cuts.\n", pPars->nLutsMax, pPars->nLutSize, pPars->nLutsOver, pPars->nVarsShared, pPars->nVarsMax ); // start the manager p = Abc_LutManStart( pPars ); p->pNtk = pNtk; // consider all nodes Abc_NtkForEachNode( pNtk, pObj, i ) { p->pObj = pObj; Abc_LutResynthesizeNode( p ); } printf( "Total nodes = %5d. Total cuts = %5d. Total gain = %5d. (%5.2f %%)\n", Abc_NtkNodeNum(pNtk), p->nCutsTotal, p->nGainTotal, 100.0 * p->nGainTotal / Abc_NtkNodeNum(pNtk) ); p->timeTotal = clock() - clk; p->timeOther = p->timeTotal - p->timeCuts - p->timeTruth - p->timeEval; PRTP( "Cuts ", p->timeCuts, p->timeTotal ); PRTP( "Truth ", p->timeTruth, p->timeTotal ); PRTP( "Eval ", p->timeEval, p->timeTotal ); PRTP( "Other ", p->timeOther, p->timeTotal ); PRTP( "TOTAL ", p->timeTotal, p->timeTotal ); Abc_LutManStop( p ); // check the resulting network if ( !Abc_NtkCheck( pNtk ) ) { printf( "Abc_LutResynthesize: The network check has failed.\n" ); return 0; } return 1; } //////////////////////////////////////////////////////////////////////// /// END OF FILE /// ////////////////////////////////////////////////////////////////////////