| /**CFile**************************************************************** |
| |
| FileName [dsdCheck.c] |
| |
| PackageName [DSD: Disjoint-support decomposition package.] |
| |
| Synopsis [Procedures to check the identity of root functions.] |
| |
| Author [Alan Mishchenko] |
| |
| Affiliation [UC Berkeley] |
| |
| Date [Ver. 8.0. Started - September 22, 2003.] |
| |
| Revision [$Id: dsdCheck.c,v 1.0 2002/22/09 00:00:00 alanmi Exp $] |
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| ***********************************************************************/ |
| |
| #include "dsdInt.h" |
| |
| ABC_NAMESPACE_IMPL_START |
| |
| |
| //////////////////////////////////////////////////////////////////////// |
| /// DECLARATIONS /// |
| //////////////////////////////////////////////////////////////////////// |
| |
| typedef struct Dsd_Cache_t_ Dds_Cache_t; |
| typedef struct Dsd_Entry_t_ Dsd_Entry_t; |
| |
| struct Dsd_Cache_t_ |
| { |
| Dsd_Entry_t * pTable; |
| int nTableSize; |
| int nSuccess; |
| int nFailure; |
| }; |
| |
| struct Dsd_Entry_t_ |
| { |
| DdNode * bX[5]; |
| }; |
| |
| static Dds_Cache_t * pCache; |
| |
| static int Dsd_CheckRootFunctionIdentity_rec( DdManager * dd, DdNode * bF1, DdNode * bF2, DdNode * bC1, DdNode * bC2 ); |
| |
| //////////////////////////////////////////////////////////////////////// |
| /// FUNCTION DEFINITIONS /// |
| //////////////////////////////////////////////////////////////////////// |
| |
| /**Function******************************************************************** |
| |
| Synopsis [(Re)allocates the local cache.] |
| |
| Description [] |
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| SideEffects [] |
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| SeeAlso [] |
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| ******************************************************************************/ |
| void Dsd_CheckCacheAllocate( int nEntries ) |
| { |
| int nRequested; |
| |
| pCache = ABC_ALLOC( Dds_Cache_t, 1 ); |
| memset( pCache, 0, sizeof(Dds_Cache_t) ); |
| |
| // check what is the size of the current cache |
| nRequested = Abc_PrimeCudd( nEntries ); |
| if ( pCache->nTableSize != nRequested ) |
| { // the current size is different |
| // deallocate the old, allocate the new |
| if ( pCache->nTableSize ) |
| Dsd_CheckCacheDeallocate(); |
| // allocate memory for the hash table |
| pCache->nTableSize = nRequested; |
| pCache->pTable = ABC_ALLOC( Dsd_Entry_t, nRequested ); |
| } |
| // otherwise, there is no need to allocate, just clean |
| Dsd_CheckCacheClear(); |
| // printf( "\nThe number of allocated cache entries = %d.\n\n", pCache->nTableSize ); |
| } |
| |
| /**Function******************************************************************** |
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| Synopsis [Deallocates the local cache.] |
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| Description [] |
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| SideEffects [] |
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| SeeAlso [] |
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| ******************************************************************************/ |
| void Dsd_CheckCacheDeallocate() |
| { |
| ABC_FREE( pCache->pTable ); |
| ABC_FREE( pCache ); |
| } |
| |
| /**Function******************************************************************** |
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| Synopsis [Clears the local cache.] |
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| Description [] |
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| SideEffects [] |
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| SeeAlso [] |
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| ******************************************************************************/ |
| void Dsd_CheckCacheClear() |
| { |
| int i; |
| for ( i = 0; i < pCache->nTableSize; i++ ) |
| pCache->pTable[0].bX[0] = NULL; |
| } |
| |
| |
| /**Function******************************************************************** |
| |
| Synopsis [Checks whether it is true that bF1(bC1=0) == bF2(bC2=0).] |
| |
| Description [] |
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| SideEffects [] |
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| SeeAlso [] |
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| ******************************************************************************/ |
| int Dsd_CheckRootFunctionIdentity( DdManager * dd, DdNode * bF1, DdNode * bF2, DdNode * bC1, DdNode * bC2 ) |
| { |
| int RetValue; |
| // pCache->nSuccess = 0; |
| // pCache->nFailure = 0; |
| RetValue = Dsd_CheckRootFunctionIdentity_rec(dd, bF1, bF2, bC1, bC2); |
| // printf( "Cache success = %d. Cache failure = %d.\n", pCache->nSuccess, pCache->nFailure ); |
| return RetValue; |
| } |
| |
| /**Function******************************************************************** |
| |
| Synopsis [Performs the recursive step of Dsd_CheckRootFunctionIdentity().] |
| |
| Description [] |
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| SideEffects [] |
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| SeeAlso [] |
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| ******************************************************************************/ |
| int Dsd_CheckRootFunctionIdentity_rec( DdManager * dd, DdNode * bF1, DdNode * bF2, DdNode * bC1, DdNode * bC2 ) |
| { |
| unsigned HKey; |
| |
| // if either bC1 or bC2 is zero, the test is true |
| // if ( bC1 == b0 || bC2 == b0 ) return 1; |
| assert( bC1 != b0 ); |
| assert( bC2 != b0 ); |
| |
| // if both bC1 and bC2 are one - perform comparison |
| if ( bC1 == b1 && bC2 == b1 ) return (int)( bF1 == bF2 ); |
| |
| if ( bF1 == b0 ) |
| return Cudd_bddLeq( dd, bC2, Cudd_Not(bF2) ); |
| |
| if ( bF1 == b1 ) |
| return Cudd_bddLeq( dd, bC2, bF2 ); |
| |
| if ( bF2 == b0 ) |
| return Cudd_bddLeq( dd, bC1, Cudd_Not(bF1) ); |
| |
| if ( bF2 == b1 ) |
| return Cudd_bddLeq( dd, bC1, bF1 ); |
| |
| // otherwise, keep expanding |
| |
| // check cache |
| // HKey = _Hash( ((unsigned)bF1), ((unsigned)bF2), ((unsigned)bC1), ((unsigned)bC2) ); |
| HKey = hashKey4( bF1, bF2, bC1, bC2, pCache->nTableSize ); |
| if ( pCache->pTable[HKey].bX[0] == bF1 && |
| pCache->pTable[HKey].bX[1] == bF2 && |
| pCache->pTable[HKey].bX[2] == bC1 && |
| pCache->pTable[HKey].bX[3] == bC2 ) |
| { |
| pCache->nSuccess++; |
| return (int)(ABC_PTRUINT_T)pCache->pTable[HKey].bX[4]; // the last bit records the result (yes/no) |
| } |
| else |
| { |
| |
| // determine the top variables |
| int RetValue; |
| DdNode * bA[4] = { bF1, bF2, bC1, bC2 }; // arguments |
| DdNode * bAR[4] = { Cudd_Regular(bF1), Cudd_Regular(bF2), Cudd_Regular(bC1), Cudd_Regular(bC2) }; // regular arguments |
| int CurLevel[4] = { cuddI(dd,bAR[0]->index), cuddI(dd,bAR[1]->index), cuddI(dd,bAR[2]->index), cuddI(dd,bAR[3]->index) }; |
| int TopLevel = CUDD_CONST_INDEX; |
| int i; |
| DdNode * bE[4], * bT[4]; |
| DdNode * bF1next, * bF2next, * bC1next, * bC2next; |
| |
| pCache->nFailure++; |
| |
| // determine the top level |
| for ( i = 0; i < 4; i++ ) |
| if ( TopLevel > CurLevel[i] ) |
| TopLevel = CurLevel[i]; |
| |
| // compute the cofactors |
| for ( i = 0; i < 4; i++ ) |
| if ( TopLevel == CurLevel[i] ) |
| { |
| if ( bA[i] != bAR[i] ) // complemented |
| { |
| bE[i] = Cudd_Not(cuddE(bAR[i])); |
| bT[i] = Cudd_Not(cuddT(bAR[i])); |
| } |
| else |
| { |
| bE[i] = cuddE(bAR[i]); |
| bT[i] = cuddT(bAR[i]); |
| } |
| } |
| else |
| bE[i] = bT[i] = bA[i]; |
| |
| // solve subproblems |
| // three cases are possible |
| |
| // (1) the top var belongs to both C1 and C2 |
| // in this case, any cofactor of F1 and F2 will do, |
| // as long as the corresponding cofactor of C1 and C2 is not equal to 0 |
| if ( TopLevel == CurLevel[2] && TopLevel == CurLevel[3] ) |
| { |
| if ( bE[2] != b0 ) // C1 |
| { |
| bF1next = bE[0]; |
| bC1next = bE[2]; |
| } |
| else |
| { |
| bF1next = bT[0]; |
| bC1next = bT[2]; |
| } |
| if ( bE[3] != b0 ) // C2 |
| { |
| bF2next = bE[1]; |
| bC2next = bE[3]; |
| } |
| else |
| { |
| bF2next = bT[1]; |
| bC2next = bT[3]; |
| } |
| RetValue = Dsd_CheckRootFunctionIdentity_rec( dd, bF1next, bF2next, bC1next, bC2next ); |
| } |
| // (2) the top var belongs to either C1 or C2 |
| // in this case normal splitting of cofactors |
| else if ( TopLevel == CurLevel[2] && TopLevel != CurLevel[3] ) |
| { |
| if ( bE[2] != b0 ) // C1 |
| { |
| bF1next = bE[0]; |
| bC1next = bE[2]; |
| } |
| else |
| { |
| bF1next = bT[0]; |
| bC1next = bT[2]; |
| } |
| // split around this variable |
| RetValue = Dsd_CheckRootFunctionIdentity_rec( dd, bF1next, bE[1], bC1next, bE[3] ); |
| if ( RetValue == 1 ) // test another branch; otherwise, there is no need to test |
| RetValue = Dsd_CheckRootFunctionIdentity_rec( dd, bF1next, bT[1], bC1next, bT[3] ); |
| } |
| else if ( TopLevel != CurLevel[2] && TopLevel == CurLevel[3] ) |
| { |
| if ( bE[3] != b0 ) // C2 |
| { |
| bF2next = bE[1]; |
| bC2next = bE[3]; |
| } |
| else |
| { |
| bF2next = bT[1]; |
| bC2next = bT[3]; |
| } |
| // split around this variable |
| RetValue = Dsd_CheckRootFunctionIdentity_rec( dd, bE[0], bF2next, bE[2], bC2next ); |
| if ( RetValue == 1 ) // test another branch; otherwise, there is no need to test |
| RetValue = Dsd_CheckRootFunctionIdentity_rec( dd, bT[0], bF2next, bT[2], bC2next ); |
| } |
| // (3) the top var does not belong to C1 and C2 |
| // in this case normal splitting of cofactors |
| else // if ( TopLevel != CurLevel[2] && TopLevel != CurLevel[3] ) |
| { |
| // split around this variable |
| RetValue = Dsd_CheckRootFunctionIdentity_rec( dd, bE[0], bE[1], bE[2], bE[3] ); |
| if ( RetValue == 1 ) // test another branch; otherwise, there is no need to test |
| RetValue = Dsd_CheckRootFunctionIdentity_rec( dd, bT[0], bT[1], bT[2], bT[3] ); |
| } |
| |
| // set cache |
| for ( i = 0; i < 4; i++ ) |
| pCache->pTable[HKey].bX[i] = bA[i]; |
| pCache->pTable[HKey].bX[4] = (DdNode*)(ABC_PTRUINT_T)RetValue; |
| |
| return RetValue; |
| } |
| } |
| |
| //////////////////////////////////////////////////////////////////////// |
| /// END OF FILE /// |
| //////////////////////////////////////////////////////////////////////// |
| |
| ABC_NAMESPACE_IMPL_END |
| |
