diff options
Diffstat (limited to 'src/base/seq/seqFpgaIter.c')
| -rw-r--r-- | src/base/seq/seqFpgaIter.c | 217 |
1 files changed, 214 insertions, 3 deletions
diff --git a/src/base/seq/seqFpgaIter.c b/src/base/seq/seqFpgaIter.c index cb0c739b..c2777606 100644 --- a/src/base/seq/seqFpgaIter.c +++ b/src/base/seq/seqFpgaIter.c @@ -6,7 +6,7 @@ PackageName [Construction and manipulation of sequential AIGs.] - Synopsis [] + Synopsis [Iterative delay computation in FPGA mapping/retiming package.] Author [Alan Mishchenko] @@ -19,18 +19,25 @@ ***********************************************************************/ #include "seqInt.h" +#include "main.h" +#include "fpga.h" //////////////////////////////////////////////////////////////////////// /// DECLARATIONS /// //////////////////////////////////////////////////////////////////////// +static void Seq_FpgaMappingCollectNode_rec( Abc_Obj_t * pAnd, Vec_Ptr_t * vMapping, Vec_Vec_t * vMapCuts ); +static Cut_Cut_t * Seq_FpgaMappingSelectCut( Abc_Obj_t * pAnd ); + +extern Cut_Man_t * Abc_NtkSeqCuts( Abc_Ntk_t * pNtk, Cut_Params_t * pParams ); + //////////////////////////////////////////////////////////////////////// /// FUNCTION DEFINITIONS /// //////////////////////////////////////////////////////////////////////// /**Function************************************************************* - Synopsis [] + Synopsis [Computes the retiming lags for FPGA mapping.] Description [] @@ -39,10 +46,214 @@ SeeAlso [] ***********************************************************************/ -void Seq_NtkSeqFpgaMapping( Abc_Ntk_t * pNtk, int fVerbose ) +void Seq_FpgaMappingDelays( Abc_Ntk_t * pNtk, int fVerbose ) { + Abc_Seq_t * p = pNtk->pManFunc; + Cut_Params_t Params, * pParams = &Params; + Abc_Obj_t * pObj; + int i, clk; + + // get the LUT library + p->nVarsMax = Fpga_LutLibReadVarMax( Abc_FrameReadLibLut() ); + + // set defaults for cut computation + memset( pParams, 0, sizeof(Cut_Params_t) ); + pParams->nVarsMax = p->nVarsMax; // the max cut size ("k" of the k-feasible cuts) + pParams->nKeepMax = 1000; // the max number of cuts kept at a node + pParams->fTruth = 0; // compute truth tables + pParams->fFilter = 1; // filter dominated cuts + pParams->fSeq = 1; // compute sequential cuts + pParams->fVerbose = 0; // the verbosiness flag + + // compute the cuts +clk = clock(); + p->pCutMan = Abc_NtkSeqCuts( pNtk, pParams ); +p->timeCuts = clock() - clk; + if ( fVerbose ) + Cut_ManPrintStats( p->pCutMan ); + + // compute the delays +clk = clock(); + Seq_NtkRetimeDelayLags( pNtk, fVerbose ); +p->timeDelay = clock() - clk; + + // collect the nodes and cuts used in the mapping + p->vMapAnds = Vec_PtrAlloc( 1000 ); + p->vMapCuts = Vec_VecAlloc( 1000 ); + Abc_NtkIncrementTravId( pNtk ); + Abc_NtkForEachPo( pNtk, pObj, i ) + Seq_FpgaMappingCollectNode_rec( Abc_ObjFanin0(pObj), p->vMapAnds, p->vMapCuts ); + +printf( "The number of LUTs = %d.\n", Vec_PtrSize(p->vMapAnds) ); + + // remove the cuts + Cut_ManStop( p->pCutMan ); + p->pCutMan = NULL; } +/**Function************************************************************* + + Synopsis [Derives the parameters of the best mapping/retiming for one node.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Seq_FpgaMappingCollectNode_rec( Abc_Obj_t * pAnd, Vec_Ptr_t * vMapping, Vec_Vec_t * vMapCuts ) +{ + Abc_Obj_t * pFanin; + Cut_Cut_t * pCutBest; + int k; + + // skip if this is a non-PI node + if ( !Abc_NodeIsAigAnd(pAnd) ) + return; + // skip a visited node + if ( Abc_NodeIsTravIdCurrent(pAnd) ) + return; + Abc_NodeSetTravIdCurrent(pAnd); + + // visit the fanins of the node + pCutBest = Seq_FpgaMappingSelectCut( pAnd ); + for ( k = 0; k < (int)pCutBest->nLeaves; k++ ) + { + pFanin = Abc_NtkObj( pAnd->pNtk, pCutBest->pLeaves[k] >> 8 ); + Seq_FpgaMappingCollectNode_rec( pFanin, vMapping, vMapCuts ); + } + + // add this node + Vec_PtrPush( vMapping, pAnd ); + for ( k = 0; k < (int)pCutBest->nLeaves; k++ ) + Vec_VecPush( vMapCuts, Vec_PtrSize(vMapping)-1, (void *)pCutBest->pLeaves[k] ); + +//printf( "Adding %d.\n", pAnd->Id ); +} + +/**Function************************************************************* + + Synopsis [Selects the best cut to represent the node in the mapping.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +Cut_Cut_t * Seq_FpgaMappingSelectCut( Abc_Obj_t * pAnd ) +{ + Abc_Obj_t * pFanin; + Cut_Cut_t * pCut, * pCutBest, * pList; + float CostCur, CostMin = ABC_INFINITY; + int ArrivalCut, ArrivalMin, i; + // get the arrival time of the best non-trivial cut + ArrivalMin = Seq_NodeGetLValue( pAnd ); + // iterate through the cuts and with the one with the minimum cost + pList = Abc_NodeReadCuts( Seq_NodeCutMan(pAnd), pAnd ); + CostMin = ABC_INFINITY; + pCutBest = NULL; + for ( pCut = pList->pNext; pCut; pCut = pCut->pNext ) + { + ArrivalCut = *((int *)&pCut->uSign); + assert( ArrivalCut >= ArrivalMin ); + if ( ArrivalCut > ArrivalMin ) + continue; + CostCur = 0.0; + for ( i = 0; i < (int)pCut->nLeaves; i++ ) + { + pFanin = Abc_NtkObj( pAnd->pNtk, pCut->pLeaves[i] >> 8 ); + if ( Abc_ObjIsPi(pFanin) ) + continue; + if ( Abc_NodeIsTravIdCurrent(pFanin) ) + continue; + CostCur += (float)(1.0 / Abc_ObjFanoutNum(pFanin)); + } + if ( CostMin > CostCur ) + { + CostMin = CostCur; + pCutBest = pCut; + } + } + assert( pCutBest != NULL ); + return pCutBest; +} + + +/**Function************************************************************* + + Synopsis [Computes the l-value of the cut.] + + Description [The node should be internal.] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +static inline int Seq_FpgaCutUpdateLValue( Cut_Cut_t * pCut, Abc_Obj_t * pObj, int Fi ) +{ + Abc_Obj_t * pFanin; + int i, lValueMax, lValueCur; + assert( Abc_NodeIsAigAnd(pObj) ); + lValueMax = -ABC_INFINITY; + for ( i = 0; i < (int)pCut->nLeaves; i++ ) + { +// lValue0 = Seq_NodeGetLValue(Abc_ObjFanin0(pObj)) - Fi * Abc_ObjFaninL0(pObj); + pFanin = Abc_NtkObj(pObj->pNtk, pCut->pLeaves[i] >> 8); + lValueCur = Seq_NodeGetLValue(pFanin) - Fi * (pCut->pLeaves[i] & 255); + if ( lValueMax < lValueCur ) + lValueMax = lValueCur; + } + lValueMax += 1; + *((int *)&pCut->uSign) = lValueMax; + return lValueMax; +} + +/**Function************************************************************* + + Synopsis [Computes the l-value of the node.] + + Description [The node can be internal or a PO.] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +int Seq_FpgaNodeUpdateLValue( Abc_Obj_t * pObj, int Fi ) +{ + Cut_Cut_t * pCut, * pList; + int lValueNew, lValueOld, lValueCut; + assert( !Abc_ObjIsPi(pObj) ); + assert( Abc_ObjFaninNum(pObj) > 0 ); + if ( Abc_ObjIsPo(pObj) ) + { + lValueNew = Seq_NodeGetLValue(Abc_ObjFanin0(pObj)) - Fi * Abc_ObjFaninL0(pObj); + return (lValueNew > Fi)? SEQ_UPDATE_FAIL : SEQ_UPDATE_NO; + } + // get the arrival time of the best non-trivial cut + pList = Abc_NodeReadCuts( Seq_NodeCutMan(pObj), pObj ); + lValueNew = ABC_INFINITY; + for ( pCut = pList->pNext; pCut; pCut = pCut->pNext ) + { + lValueCut = Seq_FpgaCutUpdateLValue( pCut, pObj, Fi ); + if ( lValueNew > lValueCut ) + lValueNew = lValueCut; + } + // compare the arrival time with the previous arrival time + lValueOld = Seq_NodeGetLValue(pObj); +// if ( lValueNew == lValueOld ) + if ( lValueNew <= lValueOld ) + return SEQ_UPDATE_NO; +//printf( "%d ", lValueNew ); + Seq_NodeSetLValue( pObj, lValueNew ); + return SEQ_UPDATE_YES; +} + + //////////////////////////////////////////////////////////////////////// /// END OF FILE /// //////////////////////////////////////////////////////////////////////// |