| /**CFile**************************************************************** |
| |
| FileName [darCut.c] |
| |
| SystemName [ABC: Logic synthesis and verification system.] |
| |
| PackageName [DAG-aware AIG rewriting.] |
| |
| Synopsis [Computation of 4-input cuts.] |
| |
| Author [Alan Mishchenko] |
| |
| Affiliation [UC Berkeley] |
| |
| Date [Ver. 1.0. Started - April 28, 2007.] |
| |
| Revision [$Id: darCut.c,v 1.00 2007/04/28 00:00:00 alanmi Exp $] |
| |
| ***********************************************************************/ |
| |
| #include "darInt.h" |
| |
| ABC_NAMESPACE_IMPL_START |
| |
| |
| //////////////////////////////////////////////////////////////////////// |
| /// DECLARATIONS /// |
| //////////////////////////////////////////////////////////////////////// |
| |
| //////////////////////////////////////////////////////////////////////// |
| /// FUNCTION DEFINITIONS /// |
| //////////////////////////////////////////////////////////////////////// |
| |
| /**Function************************************************************* |
| |
| Synopsis [Prints one cut.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| void Dar_CutPrint( Dar_Cut_t * pCut ) |
| { |
| unsigned i; |
| printf( "{" ); |
| for ( i = 0; i < pCut->nLeaves; i++ ) |
| printf( " %d", pCut->pLeaves[i] ); |
| printf( " }\n" ); |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Prints one cut.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| void Dar_ObjCutPrint( Aig_Man_t * p, Aig_Obj_t * pObj ) |
| { |
| Dar_Cut_t * pCut; |
| int i; |
| printf( "Cuts for node %d:\n", pObj->Id ); |
| Dar_ObjForEachCut( pObj, pCut, i ) |
| Dar_CutPrint( pCut ); |
| // printf( "\n" ); |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Returns the number of 1s in the machine word.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline int Dar_WordCountOnes( unsigned uWord ) |
| { |
| uWord = (uWord & 0x55555555) + ((uWord>>1) & 0x55555555); |
| uWord = (uWord & 0x33333333) + ((uWord>>2) & 0x33333333); |
| uWord = (uWord & 0x0F0F0F0F) + ((uWord>>4) & 0x0F0F0F0F); |
| uWord = (uWord & 0x00FF00FF) + ((uWord>>8) & 0x00FF00FF); |
| return (uWord & 0x0000FFFF) + (uWord>>16); |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Compute the cost of the cut.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline int Dar_CutFindValue( Dar_Man_t * p, Dar_Cut_t * pCut ) |
| { |
| Aig_Obj_t * pLeaf; |
| int i, Value, nOnes; |
| assert( pCut->fUsed ); |
| Value = 0; |
| nOnes = 0; |
| Dar_CutForEachLeaf( p->pAig, pCut, pLeaf, i ) |
| { |
| if ( pLeaf == NULL ) |
| return 0; |
| assert( pLeaf != NULL ); |
| Value += pLeaf->nRefs; |
| nOnes += (pLeaf->nRefs == 1); |
| } |
| if ( pCut->nLeaves < 2 ) |
| return 1001; |
| // Value = Value * 100 / pCut->nLeaves; |
| if ( Value > 1000 ) |
| Value = 1000; |
| if ( nOnes > 3 ) |
| Value = 5 - nOnes; |
| return Value; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Returns the next free cut to use.] |
| |
| Description [Uses the cut with the smallest value.] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline Dar_Cut_t * Dar_CutFindFree( Dar_Man_t * p, Aig_Obj_t * pObj ) |
| { |
| Dar_Cut_t * pCut, * pCutMax; |
| int i; |
| pCutMax = NULL; |
| Dar_ObjForEachCutAll( pObj, pCut, i ) |
| { |
| if ( pCut->fUsed == 0 ) |
| return pCut; |
| if ( pCut->nLeaves < 3 ) |
| continue; |
| if ( pCutMax == NULL || pCutMax->Value > pCut->Value ) |
| pCutMax = pCut; |
| } |
| if ( pCutMax == NULL ) |
| { |
| Dar_ObjForEachCutAll( pObj, pCut, i ) |
| { |
| if ( pCut->nLeaves < 2 ) |
| continue; |
| if ( pCutMax == NULL || pCutMax->Value > pCut->Value ) |
| pCutMax = pCut; |
| } |
| } |
| if ( pCutMax == NULL ) |
| { |
| Dar_ObjForEachCutAll( pObj, pCut, i ) |
| { |
| if ( pCutMax == NULL || pCutMax->Value > pCut->Value ) |
| pCutMax = pCut; |
| } |
| } |
| assert( pCutMax != NULL ); |
| pCutMax->fUsed = 0; |
| return pCutMax; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Returns 1 if pDom is contained in pCut.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline int Dar_CutCheckDominance( Dar_Cut_t * pDom, Dar_Cut_t * pCut ) |
| { |
| int i, k; |
| assert( pDom->fUsed && pCut->fUsed ); |
| 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 [Returns 1 if the cut is contained.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline int Dar_CutFilter( Aig_Obj_t * pObj, Dar_Cut_t * pCut ) |
| { |
| Dar_Cut_t * pTemp; |
| int i; |
| assert( pCut->fUsed ); |
| // go through the cuts of the node |
| Dar_ObjForEachCut( pObj, pTemp, i ) |
| { |
| if ( pTemp == pCut ) |
| continue; |
| if ( pTemp->nLeaves > pCut->nLeaves ) |
| { |
| // skip the non-contained cuts |
| if ( (pTemp->uSign & pCut->uSign) != pCut->uSign ) |
| continue; |
| // check containment seriously |
| if ( Dar_CutCheckDominance( pCut, pTemp ) ) |
| { |
| // remove contained cut |
| pTemp->fUsed = 0; |
| } |
| } |
| else |
| { |
| // skip the non-contained cuts |
| if ( (pTemp->uSign & pCut->uSign) != pTemp->uSign ) |
| continue; |
| // check containment seriously |
| if ( Dar_CutCheckDominance( pTemp, pCut ) ) |
| { |
| // remove the given cut |
| pCut->fUsed = 0; |
| return 1; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Merges two cuts.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline int Dar_CutMergeOrdered( Dar_Cut_t * pC, Dar_Cut_t * pC0, Dar_Cut_t * pC1 ) |
| { |
| int i, k, c; |
| assert( pC0->nLeaves >= pC1->nLeaves ); |
| |
| // the case of the largest cut sizes |
| if ( pC0->nLeaves == 4 && pC1->nLeaves == 4 ) |
| { |
| if ( pC0->uSign != pC1->uSign ) |
| return 0; |
| for ( i = 0; i < (int)pC0->nLeaves; i++ ) |
| if ( pC0->pLeaves[i] != pC1->pLeaves[i] ) |
| return 0; |
| for ( i = 0; i < (int)pC0->nLeaves; i++ ) |
| pC->pLeaves[i] = pC0->pLeaves[i]; |
| pC->nLeaves = pC0->nLeaves; |
| return 1; |
| } |
| |
| // the case when one of the cuts is the largest |
| if ( pC0->nLeaves == 4 ) |
| { |
| if ( (pC0->uSign & pC1->uSign) != pC1->uSign ) |
| return 0; |
| for ( i = 0; i < (int)pC1->nLeaves; i++ ) |
| { |
| for ( k = (int)pC0->nLeaves - 1; k >= 0; k-- ) |
| if ( pC0->pLeaves[k] == pC1->pLeaves[i] ) |
| break; |
| if ( k == -1 ) // did not find |
| return 0; |
| } |
| for ( i = 0; i < (int)pC0->nLeaves; i++ ) |
| pC->pLeaves[i] = pC0->pLeaves[i]; |
| pC->nLeaves = pC0->nLeaves; |
| return 1; |
| } |
| |
| // compare two cuts with different numbers |
| i = k = 0; |
| for ( c = 0; c < 4; c++ ) |
| { |
| if ( k == (int)pC1->nLeaves ) |
| { |
| if ( i == (int)pC0->nLeaves ) |
| { |
| pC->nLeaves = c; |
| return 1; |
| } |
| pC->pLeaves[c] = pC0->pLeaves[i++]; |
| continue; |
| } |
| if ( i == (int)pC0->nLeaves ) |
| { |
| if ( k == (int)pC1->nLeaves ) |
| { |
| pC->nLeaves = c; |
| return 1; |
| } |
| pC->pLeaves[c] = pC1->pLeaves[k++]; |
| continue; |
| } |
| if ( pC0->pLeaves[i] < pC1->pLeaves[k] ) |
| { |
| pC->pLeaves[c] = pC0->pLeaves[i++]; |
| continue; |
| } |
| if ( pC0->pLeaves[i] > pC1->pLeaves[k] ) |
| { |
| pC->pLeaves[c] = pC1->pLeaves[k++]; |
| continue; |
| } |
| pC->pLeaves[c] = pC0->pLeaves[i++]; |
| k++; |
| } |
| if ( i < (int)pC0->nLeaves || k < (int)pC1->nLeaves ) |
| return 0; |
| pC->nLeaves = c; |
| return 1; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Prepares the object for FPGA mapping.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline int Dar_CutMerge( Dar_Cut_t * pCut, Dar_Cut_t * pCut0, Dar_Cut_t * pCut1 ) |
| { |
| assert( !pCut->fUsed ); |
| // merge the nodes |
| if ( pCut0->nLeaves <= pCut1->nLeaves ) |
| { |
| if ( !Dar_CutMergeOrdered( pCut, pCut1, pCut0 ) ) |
| return 0; |
| } |
| else |
| { |
| if ( !Dar_CutMergeOrdered( pCut, pCut0, pCut1 ) ) |
| return 0; |
| } |
| pCut->uSign = pCut0->uSign | pCut1->uSign; |
| pCut->fUsed = 1; |
| return 1; |
| } |
| |
| |
| /**Function************************************************************* |
| |
| Synopsis [Computes the stretching phase of the cut w.r.t. the merged cut.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline unsigned Dar_CutTruthPhase( Dar_Cut_t * pCut, Dar_Cut_t * pCut1 ) |
| { |
| unsigned uPhase = 0; |
| int i, k; |
| for ( i = k = 0; i < (int)pCut->nLeaves; i++ ) |
| { |
| if ( k == (int)pCut1->nLeaves ) |
| break; |
| if ( pCut->pLeaves[i] < pCut1->pLeaves[k] ) |
| continue; |
| assert( pCut->pLeaves[i] == pCut1->pLeaves[k] ); |
| uPhase |= (1 << i); |
| k++; |
| } |
| return uPhase; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Swaps two advancent variables of the truth table.] |
| |
| Description [Swaps variable iVar and iVar+1.] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline unsigned Dar_CutTruthSwapAdjacentVars( unsigned uTruth, int iVar ) |
| { |
| assert( iVar >= 0 && iVar <= 2 ); |
| if ( iVar == 0 ) |
| return (uTruth & 0x99999999) | ((uTruth & 0x22222222) << 1) | ((uTruth & 0x44444444) >> 1); |
| if ( iVar == 1 ) |
| return (uTruth & 0xC3C3C3C3) | ((uTruth & 0x0C0C0C0C) << 2) | ((uTruth & 0x30303030) >> 2); |
| if ( iVar == 2 ) |
| return (uTruth & 0xF00FF00F) | ((uTruth & 0x00F000F0) << 4) | ((uTruth & 0x0F000F00) >> 4); |
| assert( 0 ); |
| return 0; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Swaps polarity of the variable.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline unsigned Dar_CutTruthSwapPolarity( unsigned uTruth, int iVar ) |
| { |
| assert( iVar >= 0 && iVar <= 3 ); |
| if ( iVar == 0 ) |
| return ((uTruth & 0xAAAA) >> 1) | ((uTruth & 0x5555) << 1); |
| if ( iVar == 1 ) |
| return ((uTruth & 0xCCCC) >> 2) | ((uTruth & 0x3333) << 2); |
| if ( iVar == 2 ) |
| return ((uTruth & 0xF0F0) >> 4) | ((uTruth & 0x0F0F) << 4); |
| if ( iVar == 3 ) |
| return ((uTruth & 0xFF00) >> 8) | ((uTruth & 0x00FF) << 8); |
| assert( 0 ); |
| return 0; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Expands the truth table according to the phase.] |
| |
| Description [The input and output truth tables are in pIn/pOut. The current number |
| of variables is nVars. The total number of variables in nVarsAll. The last argument |
| (Phase) contains shows where the variables should go.] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline unsigned Dar_CutTruthStretch( unsigned uTruth, int nVars, unsigned Phase ) |
| { |
| int i, k, Var = nVars - 1; |
| for ( i = 3; i >= 0; i-- ) |
| if ( Phase & (1 << i) ) |
| { |
| for ( k = Var; k < i; k++ ) |
| uTruth = Dar_CutTruthSwapAdjacentVars( uTruth, k ); |
| Var--; |
| } |
| assert( Var == -1 ); |
| return uTruth; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Shrinks the truth table according to the phase.] |
| |
| Description [The input and output truth tables are in pIn/pOut. The current number |
| of variables is nVars. The total number of variables in nVarsAll. The last argument |
| (Phase) contains shows what variables should remain.] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline unsigned Dar_CutTruthShrink( unsigned uTruth, int nVars, unsigned Phase ) |
| { |
| int i, k, Var = 0; |
| for ( i = 0; i < 4; i++ ) |
| if ( Phase & (1 << i) ) |
| { |
| for ( k = i-1; k >= Var; k-- ) |
| uTruth = Dar_CutTruthSwapAdjacentVars( uTruth, k ); |
| Var++; |
| } |
| return uTruth; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Sort variables by their ID.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| unsigned Dar_CutSortVars( unsigned uTruth, int * pVars ) |
| { |
| int i, Temp, fChange, Counter = 0; |
| // replace -1 by large number |
| for ( i = 0; i < 4; i++ ) |
| { |
| if ( pVars[i] == -1 ) |
| pVars[i] = 0x3FFFFFFF; |
| else |
| if ( Abc_LitIsCompl(pVars[i]) ) |
| { |
| pVars[i] = Abc_LitNot( pVars[i] ); |
| uTruth = Dar_CutTruthSwapPolarity( uTruth, i ); |
| } |
| } |
| |
| // permute variables |
| do { |
| fChange = 0; |
| for ( i = 0; i < 3; i++ ) |
| { |
| if ( pVars[i] <= pVars[i+1] ) |
| continue; |
| Counter++; |
| fChange = 1; |
| |
| Temp = pVars[i]; |
| pVars[i] = pVars[i+1]; |
| pVars[i+1] = Temp; |
| |
| uTruth = Dar_CutTruthSwapAdjacentVars( uTruth, i ); |
| } |
| } while ( fChange ); |
| |
| // replace large number by -1 |
| for ( i = 0; i < 4; i++ ) |
| { |
| if ( pVars[i] == 0x3FFFFFFF ) |
| pVars[i] = -1; |
| // printf( "%d ", pVars[i] ); |
| } |
| // printf( "\n" ); |
| |
| return uTruth; |
| } |
| |
| |
| |
| /**Function************************************************************* |
| |
| Synopsis [Performs truth table computation.] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline unsigned Dar_CutTruth( Dar_Cut_t * pCut, Dar_Cut_t * pCut0, Dar_Cut_t * pCut1, int fCompl0, int fCompl1 ) |
| { |
| unsigned uTruth0 = fCompl0 ? ~pCut0->uTruth : pCut0->uTruth; |
| unsigned uTruth1 = fCompl1 ? ~pCut1->uTruth : pCut1->uTruth; |
| uTruth0 = Dar_CutTruthStretch( uTruth0, pCut0->nLeaves, Dar_CutTruthPhase(pCut, pCut0) ); |
| uTruth1 = Dar_CutTruthStretch( uTruth1, pCut1->nLeaves, Dar_CutTruthPhase(pCut, pCut1) ); |
| return uTruth0 & uTruth1; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [Minimize support of the cut.] |
| |
| Description [Returns 1 if the node's support has changed] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| static inline int Dar_CutSuppMinimize( Dar_Cut_t * pCut ) |
| { |
| unsigned uMasks[4][2] = { |
| { 0x5555, 0xAAAA }, |
| { 0x3333, 0xCCCC }, |
| { 0x0F0F, 0xF0F0 }, |
| { 0x00FF, 0xFF00 } |
| }; |
| unsigned uPhase = 0, uTruth = 0xFFFF & pCut->uTruth; |
| int i, k, nLeaves; |
| assert( pCut->fUsed ); |
| // compute the support of the cut's function |
| nLeaves = pCut->nLeaves; |
| for ( i = 0; i < (int)pCut->nLeaves; i++ ) |
| if ( (uTruth & uMasks[i][0]) == ((uTruth & uMasks[i][1]) >> (1 << i)) ) |
| nLeaves--; |
| else |
| uPhase |= (1 << i); |
| if ( nLeaves == (int)pCut->nLeaves ) |
| return 0; |
| // shrink the truth table |
| uTruth = Dar_CutTruthShrink( uTruth, pCut->nLeaves, uPhase ); |
| pCut->uTruth = 0xFFFF & uTruth; |
| // update leaves and signature |
| pCut->uSign = 0; |
| for ( i = k = 0; i < (int)pCut->nLeaves; i++ ) |
| { |
| if ( !(uPhase & (1 << i)) ) |
| continue; |
| pCut->pLeaves[k++] = pCut->pLeaves[i]; |
| pCut->uSign |= Aig_ObjCutSign( pCut->pLeaves[i] ); |
| } |
| assert( k == nLeaves ); |
| pCut->nLeaves = nLeaves; |
| return 1; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| void Dar_ManCutsFree( Dar_Man_t * p ) |
| { |
| if ( p->pMemCuts == NULL ) |
| return; |
| Aig_MmFixedStop( p->pMemCuts, 0 ); |
| p->pMemCuts = NULL; |
| // Aig_ManCleanData( p ); |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| Dar_Cut_t * Dar_ObjPrepareCuts( Dar_Man_t * p, Aig_Obj_t * pObj ) |
| { |
| Dar_Cut_t * pCutSet, * pCut; |
| int i; |
| assert( Dar_ObjCuts(pObj) == NULL ); |
| pObj->nCuts = p->pPars->nCutsMax; |
| // create the cutset of the node |
| pCutSet = (Dar_Cut_t *)Aig_MmFixedEntryFetch( p->pMemCuts ); |
| memset( pCutSet, 0, p->pPars->nCutsMax * sizeof(Dar_Cut_t) ); |
| Dar_ObjSetCuts( pObj, pCutSet ); |
| Dar_ObjForEachCutAll( pObj, pCut, i ) |
| pCut->fUsed = 0; |
| Vec_PtrPush( p->vCutNodes, pObj ); |
| // add unit cut if needed |
| pCut = pCutSet; |
| pCut->fUsed = 1; |
| if ( Aig_ObjIsConst1(pObj) ) |
| { |
| pCut->nLeaves = 0; |
| pCut->uSign = 0; |
| pCut->uTruth = 0xFFFF; |
| } |
| else |
| { |
| pCut->nLeaves = 1; |
| pCut->pLeaves[0] = pObj->Id; |
| pCut->uSign = Aig_ObjCutSign( pObj->Id ); |
| pCut->uTruth = 0xAAAA; |
| } |
| pCut->Value = Dar_CutFindValue( p, pCut ); |
| if ( p->nCutMemUsed < Aig_MmFixedReadMemUsage(p->pMemCuts)/(1<<20) ) |
| p->nCutMemUsed = Aig_MmFixedReadMemUsage(p->pMemCuts)/(1<<20); |
| return pCutSet; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| void Dar_ManCutsRestart( Dar_Man_t * p, Aig_Obj_t * pRoot ) |
| { |
| Aig_Obj_t * pObj; |
| int i; |
| Dar_ObjSetCuts( Aig_ManConst1(p->pAig), NULL ); |
| Vec_PtrForEachEntry( Aig_Obj_t *, p->vCutNodes, pObj, i ) |
| if ( !Aig_ObjIsNone(pObj) ) |
| Dar_ObjSetCuts( pObj, NULL ); |
| Vec_PtrClear( p->vCutNodes ); |
| Aig_MmFixedRestart( p->pMemCuts ); |
| Dar_ObjPrepareCuts( p, Aig_ManConst1(p->pAig) ); |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| Dar_Cut_t * Dar_ObjComputeCuts( Dar_Man_t * p, Aig_Obj_t * pObj, int fSkipTtMin ) |
| { |
| Aig_Obj_t * pFanin0 = Aig_ObjReal_rec( Aig_ObjChild0(pObj) ); |
| Aig_Obj_t * pFanin1 = Aig_ObjReal_rec( Aig_ObjChild1(pObj) ); |
| Aig_Obj_t * pFaninR0 = Aig_Regular(pFanin0); |
| Aig_Obj_t * pFaninR1 = Aig_Regular(pFanin1); |
| Dar_Cut_t * pCutSet, * pCut0, * pCut1, * pCut; |
| int i, k; |
| |
| assert( !Aig_IsComplement(pObj) ); |
| assert( Aig_ObjIsNode(pObj) ); |
| assert( Dar_ObjCuts(pObj) == NULL ); |
| assert( Dar_ObjCuts(pFaninR0) != NULL ); |
| assert( Dar_ObjCuts(pFaninR1) != NULL ); |
| |
| // set up the first cut |
| pCutSet = Dar_ObjPrepareCuts( p, pObj ); |
| // make sure fanins cuts are computed |
| Dar_ObjForEachCut( pFaninR0, pCut0, i ) |
| Dar_ObjForEachCut( pFaninR1, pCut1, k ) |
| { |
| p->nCutsAll++; |
| // make sure K-feasible cut exists |
| if ( Dar_WordCountOnes(pCut0->uSign | pCut1->uSign) > 4 ) |
| continue; |
| // get the next cut of this node |
| pCut = Dar_CutFindFree( p, pObj ); |
| // create the new cut |
| if ( !Dar_CutMerge( pCut, pCut0, pCut1 ) ) |
| { |
| assert( !pCut->fUsed ); |
| continue; |
| } |
| p->nCutsTried++; |
| // check dominance |
| if ( Dar_CutFilter( pObj, pCut ) ) |
| { |
| assert( !pCut->fUsed ); |
| continue; |
| } |
| // compute truth table |
| pCut->uTruth = 0xFFFF & Dar_CutTruth( pCut, pCut0, pCut1, Aig_IsComplement(pFanin0), Aig_IsComplement(pFanin1) ); |
| |
| // minimize support of the cut |
| if ( !fSkipTtMin && Dar_CutSuppMinimize( pCut ) ) |
| { |
| int RetValue = Dar_CutFilter( pObj, pCut ); |
| assert( !RetValue ); |
| } |
| |
| // assign the value of the cut |
| pCut->Value = Dar_CutFindValue( p, pCut ); |
| // if the cut contains removed node, do not use it |
| if ( pCut->Value == 0 ) |
| { |
| p->nCutsSkipped++; |
| pCut->fUsed = 0; |
| } |
| else if ( pCut->nLeaves < 2 ) |
| return pCutSet; |
| } |
| // count the number of nontrivial cuts cuts |
| Dar_ObjForEachCut( pObj, pCut, i ) |
| p->nCutsUsed += pCut->fUsed; |
| // discount trivial cut |
| p->nCutsUsed--; |
| return pCutSet; |
| } |
| |
| /**Function************************************************************* |
| |
| Synopsis [] |
| |
| Description [] |
| |
| SideEffects [] |
| |
| SeeAlso [] |
| |
| ***********************************************************************/ |
| Dar_Cut_t * Dar_ObjComputeCuts_rec( Dar_Man_t * p, Aig_Obj_t * pObj ) |
| { |
| if ( Dar_ObjCuts(pObj) ) |
| return Dar_ObjCuts(pObj); |
| if ( Aig_ObjIsCi(pObj) ) |
| return Dar_ObjPrepareCuts( p, pObj ); |
| if ( Aig_ObjIsBuf(pObj) ) |
| return Dar_ObjComputeCuts_rec( p, Aig_ObjFanin0(pObj) ); |
| Dar_ObjComputeCuts_rec( p, Aig_ObjFanin0(pObj) ); |
| Dar_ObjComputeCuts_rec( p, Aig_ObjFanin1(pObj) ); |
| return Dar_ObjComputeCuts( p, pObj, 0 ); |
| } |
| |
| //////////////////////////////////////////////////////////////////////// |
| /// END OF FILE /// |
| //////////////////////////////////////////////////////////////////////// |
| |
| |
| ABC_NAMESPACE_IMPL_END |
| |
