From 0c6505a26a537dc911b6566f82d759521e527c08 Mon Sep 17 00:00:00 2001 From: Alan Mishchenko Date: Wed, 30 Jan 2008 20:01:00 -0800 Subject: Version abc80130_2 --- src/aig/cnf/cnfCut.c | 371 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 371 insertions(+) create mode 100644 src/aig/cnf/cnfCut.c (limited to 'src/aig/cnf/cnfCut.c') diff --git a/src/aig/cnf/cnfCut.c b/src/aig/cnf/cnfCut.c new file mode 100644 index 00000000..17ab0c78 --- /dev/null +++ b/src/aig/cnf/cnfCut.c @@ -0,0 +1,371 @@ +/**CFile**************************************************************** + + FileName [cnfCut.c] + + SystemName [ABC: Logic synthesis and verification system.] + + PackageName [AIG-to-CNF conversion.] + + Synopsis [] + + Author [Alan Mishchenko] + + Affiliation [UC Berkeley] + + Date [Ver. 1.0. Started - April 28, 2007.] + + Revision [$Id: cnfCut.c,v 1.00 2007/04/28 00:00:00 alanmi Exp $] + +***********************************************************************/ + +#include "cnf.h" +#include "kit.h" + +//////////////////////////////////////////////////////////////////////// +/// DECLARATIONS /// +//////////////////////////////////////////////////////////////////////// + +//////////////////////////////////////////////////////////////////////// +/// FUNCTION DEFINITIONS /// +//////////////////////////////////////////////////////////////////////// + +/**Function************************************************************* + + Synopsis [Allocates cut of the given size.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +Cnf_Cut_t * Cnf_CutAlloc( Cnf_Man_t * p, int nLeaves ) +{ + Cnf_Cut_t * pCut; + int nSize = sizeof(Cnf_Cut_t) + sizeof(int) * nLeaves + sizeof(unsigned) * Aig_TruthWordNum(nLeaves); + pCut = (Cnf_Cut_t *)Aig_MmFlexEntryFetch( p->pMemCuts, nSize ); + pCut->nFanins = nLeaves; + pCut->nWords = Aig_TruthWordNum(nLeaves); + pCut->vIsop[0] = pCut->vIsop[1] = NULL; + return pCut; +} + +/**Function************************************************************* + + Synopsis [Deallocates cut.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Cnf_CutFree( Cnf_Cut_t * pCut ) +{ + if ( pCut->vIsop[0] ) + Vec_IntFree( pCut->vIsop[0] ); + if ( pCut->vIsop[1] ) + Vec_IntFree( pCut->vIsop[1] ); +} + +/**Function************************************************************* + + Synopsis [Creates cut for the given node.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +Cnf_Cut_t * Cnf_CutCreate( Cnf_Man_t * p, Aig_Obj_t * pObj ) +{ + Dar_Cut_t * pCutBest; + Cnf_Cut_t * pCut; + unsigned * pTruth; + assert( Aig_ObjIsNode(pObj) ); + pCutBest = Dar_ObjBestCut( pObj ); + assert( pCutBest != NULL ); + assert( pCutBest->nLeaves <= 4 ); + pCut = Cnf_CutAlloc( p, pCutBest->nLeaves ); + memcpy( pCut->pFanins, pCutBest->pLeaves, sizeof(int) * pCutBest->nLeaves ); + pTruth = Cnf_CutTruth(pCut); + *pTruth = (pCutBest->uTruth << 16) | pCutBest->uTruth; + pCut->Cost = Cnf_CutSopCost( p, pCutBest ); + return pCut; +} + +/**Function************************************************************* + + Synopsis [Deallocates cut.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Cnf_CutPrint( Cnf_Cut_t * pCut ) +{ + int i; + printf( "{" ); + for ( i = 0; i < pCut->nFanins; i++ ) + printf( "%d ", pCut->pFanins[i] ); + printf( " } " ); +} + +/**Function************************************************************* + + Synopsis [Allocates cut of the given size.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Cnf_CutDeref( Cnf_Man_t * p, Cnf_Cut_t * pCut ) +{ + Aig_Obj_t * pObj; + int i; + Cnf_CutForEachLeaf( p->pManAig, pCut, pObj, i ) + { + assert( pObj->nRefs > 0 ); + pObj->nRefs--; + } +} + +/**Function************************************************************* + + Synopsis [Allocates cut of the given size.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Cnf_CutRef( Cnf_Man_t * p, Cnf_Cut_t * pCut ) +{ + Aig_Obj_t * pObj; + int i; + Cnf_CutForEachLeaf( p->pManAig, pCut, pObj, i ) + { + pObj->nRefs++; + } +} + +/**Function************************************************************* + + Synopsis [Allocates cut of the given size.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Cnf_CutUpdateRefs( Cnf_Man_t * p, Cnf_Cut_t * pCut, Cnf_Cut_t * pCutFan, Cnf_Cut_t * pCutRes ) +{ + Cnf_CutDeref( p, pCut ); + Cnf_CutDeref( p, pCutFan ); + Cnf_CutRef( p, pCutRes ); +} + +/**Function************************************************************* + + Synopsis [Merges two arrays of integers.] + + Description [Returns the number of items.] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +static inline int Cnf_CutMergeLeaves( Cnf_Cut_t * pCut, Cnf_Cut_t * pCutFan, int * pFanins ) +{ + int i, k, nFanins = 0; + for ( i = k = 0; i < pCut->nFanins && k < pCutFan->nFanins; ) + { + if ( pCut->pFanins[i] == pCutFan->pFanins[k] ) + pFanins[nFanins++] = pCut->pFanins[i], i++, k++; + else if ( pCut->pFanins[i] < pCutFan->pFanins[k] ) + pFanins[nFanins++] = pCut->pFanins[i], i++; + else + pFanins[nFanins++] = pCutFan->pFanins[k], k++; + } + for ( ; i < pCut->nFanins; i++ ) + pFanins[nFanins++] = pCut->pFanins[i]; + for ( ; k < pCutFan->nFanins; k++ ) + pFanins[nFanins++] = pCutFan->pFanins[k]; + return nFanins; +} + +/**Function************************************************************* + + Synopsis [Computes the stretching phase of the cut w.r.t. the merged cut.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +static inline unsigned Cnf_TruthPhase( Cnf_Cut_t * pCut, Cnf_Cut_t * pCut1 ) +{ + unsigned uPhase = 0; + int i, k; + for ( i = k = 0; i < pCut->nFanins; i++ ) + { + if ( k == pCut1->nFanins ) + break; + if ( pCut->pFanins[i] < pCut1->pFanins[k] ) + continue; + assert( pCut->pFanins[i] == pCut1->pFanins[k] ); + uPhase |= (1 << i); + k++; + } + return uPhase; +} + +/**Function************************************************************* + + Synopsis [Removes the fanin variable.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Cnf_CutRemoveIthVar( Cnf_Cut_t * pCut, int iVar, int iFan ) +{ + int i; + assert( pCut->pFanins[iVar] == iFan ); + pCut->nFanins--; + for ( i = iVar; i < pCut->nFanins; i++ ) + pCut->pFanins[i] = pCut->pFanins[i+1]; +} + +/**Function************************************************************* + + Synopsis [Inserts the fanin variable.] + + Description [] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +void Cnf_CutInsertIthVar( Cnf_Cut_t * pCut, int iVar, int iFan ) +{ + int i; + for ( i = pCut->nFanins; i > iVar; i-- ) + pCut->pFanins[i] = pCut->pFanins[i-1]; + pCut->pFanins[iVar] = iFan; + pCut->nFanins++; +} + +/**Function************************************************************* + + Synopsis [Merges two cuts.] + + Description [Returns NULL of the cuts cannot be merged.] + + SideEffects [] + + SeeAlso [] + +***********************************************************************/ +Cnf_Cut_t * Cnf_CutCompose( Cnf_Man_t * p, Cnf_Cut_t * pCut, Cnf_Cut_t * pCutFan, int iFan ) +{ + Cnf_Cut_t * pCutRes; + static int pFanins[32]; + unsigned * pTruth, * pTruthFan, * pTruthRes; + unsigned * pTop = p->pTruths[0], * pFan = p->pTruths[2], * pTemp = p->pTruths[3]; + unsigned uPhase, uPhaseFan; + int i, iVar, nFanins, RetValue; + + // make sure the second cut is the fanin of the first + for ( iVar = 0; iVar < pCut->nFanins; iVar++ ) + if ( pCut->pFanins[iVar] == iFan ) + break; + assert( iVar < pCut->nFanins ); + // remove this variable + Cnf_CutRemoveIthVar( pCut, iVar, iFan ); + // merge leaves of the cuts + nFanins = Cnf_CutMergeLeaves( pCut, pCutFan, pFanins ); + if ( nFanins+1 > p->nMergeLimit ) + { + Cnf_CutInsertIthVar( pCut, iVar, iFan ); + return NULL; + } + // create new cut + pCutRes = Cnf_CutAlloc( p, nFanins ); + memcpy( pCutRes->pFanins, pFanins, sizeof(int) * nFanins ); + assert( pCutRes->nFanins <= pCut->nFanins + pCutFan->nFanins ); + + // derive its truth table + // get the truth tables in the composition space + pTruth = Cnf_CutTruth(pCut); + pTruthFan = Cnf_CutTruth(pCutFan); + pTruthRes = Cnf_CutTruth(pCutRes); + for ( i = 0; i < 2*pCutRes->nWords; i++ ) + pTop[i] = pTruth[i % pCut->nWords]; + for ( i = 0; i < pCutRes->nWords; i++ ) + pFan[i] = pTruthFan[i % pCutFan->nWords]; + // move the variable to the end + uPhase = Kit_BitMask( pCutRes->nFanins+1 ) & ~(1 << iVar); + Kit_TruthShrink( pTemp, pTop, pCutRes->nFanins, pCutRes->nFanins+1, uPhase, 1 ); + // compute the phases + uPhase = Cnf_TruthPhase( pCutRes, pCut ) | (1 << pCutRes->nFanins); + uPhaseFan = Cnf_TruthPhase( pCutRes, pCutFan ); + // permute truth-tables to the common support + Kit_TruthStretch( pTemp, pTop, pCut->nFanins+1, pCutRes->nFanins+1, uPhase, 1 ); + Kit_TruthStretch( pTemp, pFan, pCutFan->nFanins, pCutRes->nFanins, uPhaseFan, 1 ); + // perform Boolean operation + Kit_TruthMux( pTruthRes, pTop, pTop+pCutRes->nWords, pFan, pCutRes->nFanins ); + // return the cut to its original condition + Cnf_CutInsertIthVar( pCut, iVar, iFan ); + // consider the simple case + if ( pCutRes->nFanins < 5 ) + { + pCutRes->Cost = p->pSopSizes[0xFFFF & *pTruthRes] + p->pSopSizes[0xFFFF & ~*pTruthRes]; + return pCutRes; + } + + // derive ISOP for positive phase + RetValue = Kit_TruthIsop( pTruthRes, pCutRes->nFanins, p->vMemory, 0 ); + pCutRes->vIsop[1] = (RetValue == -1)? NULL : Vec_IntDup( p->vMemory ); + // derive ISOP for negative phase + Kit_TruthNot( pTruthRes, pTruthRes, pCutRes->nFanins ); + RetValue = Kit_TruthIsop( pTruthRes, pCutRes->nFanins, p->vMemory, 0 ); + pCutRes->vIsop[0] = (RetValue == -1)? NULL : Vec_IntDup( p->vMemory ); + Kit_TruthNot( pTruthRes, pTruthRes, pCutRes->nFanins ); + + // compute the cut cost + if ( pCutRes->vIsop[0] == NULL || pCutRes->vIsop[1] == NULL ) + pCutRes->Cost = 127; + else if ( Vec_IntSize(pCutRes->vIsop[0]) + Vec_IntSize(pCutRes->vIsop[1]) > 127 ) + pCutRes->Cost = 127; + else + pCutRes->Cost = Vec_IntSize(pCutRes->vIsop[0]) + Vec_IntSize(pCutRes->vIsop[1]); + return pCutRes; +} + +//////////////////////////////////////////////////////////////////////// +/// END OF FILE /// +//////////////////////////////////////////////////////////////////////// + + -- cgit v1.2.3