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/**CFile****************************************************************
FileName [abcFunc.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Network and node package.]
Synopsis [Transformations between different functionality representations.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: abcFunc.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "abc.h"
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
static DdNode * Abc_ConvertSopToBdd( DdManager * dd, char * pSop, int nFanins );
static int Abc_ConvertZddToSop( DdManager * dd, DdNode * zCover, char * pSop, int nFanins, Vec_Str_t * vCube, int fPhase );
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Converts the network from SOP to BDD representation.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_NtkSopToBdd( Abc_Ntk_t * pNtk )
{
Abc_Obj_t * pNode;
DdManager * dd;
int nFaninsMax, i;
assert( Abc_NtkIsSopLogic(pNtk) );
// start the functionality manager
nFaninsMax = Abc_NtkGetFaninMax( pNtk );
if ( nFaninsMax == 0 )
printf( "Warning: The network has only constant nodes.\n" );
dd = Cudd_Init( nFaninsMax, 0, CUDD_UNIQUE_SLOTS, CUDD_CACHE_SLOTS, 0 );
// convert each node from SOP to BDD
Abc_NtkForEachNode( pNtk, pNode, i )
{
assert( pNode->pData );
pNode->pData = Abc_ConvertSopToBdd( dd, pNode->pData, Abc_ObjFaninNum(pNode) );
if ( pNode->pData == NULL )
{
printf( "Abc_NtkSopToBdd: Error while converting SOP into BDD.\n" );
return 0;
}
Cudd_Ref( pNode->pData );
}
Extra_MmFlexStop( pNtk->pManFunc, 0 );
pNtk->pManFunc = dd;
// update the network type
pNtk->ntkFunc = ABC_FUNC_BDD;
return 1;
}
/**Function*************************************************************
Synopsis [Converts the node from SOP to BDD representation.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
DdNode * Abc_ConvertSopToBdd( DdManager * dd, char * pSop, int nFanins )
{
DdNode * bCube, * bTemp, * bVar, * bRes;
char * pCube;
int i, c;
bRes = Cudd_Not(dd->one); Cudd_Ref( bRes );
for ( c = 0; ; c++ )
{
// get the cube
pCube = pSop + c * (nFanins + 3);
if ( *pCube == 0 )
break;
// construct BDD for the cube
bCube = dd->one; Cudd_Ref( bCube );
for ( i = 0; i < nFanins; i++ )
{
if ( pCube[i] == '0' )
bVar = Cudd_Not( dd->vars[i] );
else if ( pCube[i] == '1' )
bVar = dd->vars[i];
else
continue;
bCube = Cudd_bddAnd( dd, bTemp = bCube, bVar ); Cudd_Ref( bCube );
Cudd_RecursiveDeref( dd, bTemp );
}
bRes = Cudd_bddOr( dd, bTemp = bRes, bCube ); Cudd_Ref( bRes );
Cudd_RecursiveDeref( dd, bTemp );
Cudd_RecursiveDeref( dd, bCube );
}
// decide if we need to complement the result
pCube = pSop + nFanins + 1;
assert( *pCube == '0' || *pCube == '1' );
if ( *pCube == '0' )
bRes = Cudd_Not(bRes);
Cudd_Deref( bRes );
return bRes;
}
/**Function*************************************************************
Synopsis [Converts the network from BDD to SOP representation.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_NtkBddToSop( Abc_Ntk_t * pNtk )
{
Abc_Obj_t * pNode;
DdManager * dd = pNtk->pManFunc;
DdNode * bFunc;
int RetValue, i;
Vec_Str_t * vCube;
assert( Abc_NtkIsBddLogic(pNtk) );
Cudd_zddVarsFromBddVars( dd, 2 );
// allocate the new manager
pNtk->pManFunc = Extra_MmFlexStart();
// update the network type
pNtk->ntkFunc = ABC_FUNC_SOP;
// go through the objects
vCube = Vec_StrAlloc( 100 );
Abc_NtkForEachNode( pNtk, pNode, i )
{
assert( pNode->pData );
bFunc = pNode->pData;
pNode->pData = Abc_ConvertBddToSop( pNtk->pManFunc, dd, bFunc, bFunc, Abc_ObjFaninNum(pNode), vCube, -1 );
if ( pNode->pData == NULL )
return 0;
Cudd_RecursiveDeref( dd, bFunc );
}
Vec_StrFree( vCube );
// check for remaining references in the package
RetValue = Cudd_CheckZeroRef( dd );
if ( RetValue > 0 )
printf( "\nThe number of referenced nodes = %d\n\n", RetValue );
// Cudd_PrintInfo( dd, stdout );
Cudd_Quit( dd );
return 1;
}
/**Function*************************************************************
Synopsis [Converts the node from BDD to SOP representation.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_ConvertBddToSop( Extra_MmFlex_t * pMan, DdManager * dd, DdNode * bFuncOn, DdNode * bFuncOnDc, int nFanins, Vec_Str_t * vCube, int fMode )
{
int fVerify = 0;
char * pSop;
DdNode * bFuncNew, * bCover, * zCover, * zCover0, * zCover1;
int nCubes, nCubes0, nCubes1, fPhase;
assert( bFuncOn == bFuncOnDc || Cudd_bddLeq( dd, bFuncOn, bFuncOnDc ) );
if ( Cudd_IsConstant(bFuncOn) || Cudd_IsConstant(bFuncOnDc) )
{
Vec_StrFill( vCube, nFanins, '-' );
Vec_StrPush( vCube, '\0' );
if ( pMan )
pSop = Extra_MmFlexEntryFetch( pMan, nFanins + 4 );
else
pSop = ALLOC( char, nFanins + 4 );
if ( bFuncOn == Cudd_ReadLogicZero(dd) )
sprintf( pSop, "%s 0\n", vCube->pArray );
else
sprintf( pSop, "%s 1\n", vCube->pArray );
return pSop;
}
if ( fMode == -1 )
{ // try both phases
// get the ZDD of the negative polarity
bCover = Cudd_zddIsop( dd, Cudd_Not(bFuncOnDc), Cudd_Not(bFuncOn), &zCover0 );
Cudd_Ref( zCover0 );
Cudd_Ref( bCover );
Cudd_RecursiveDeref( dd, bCover );
nCubes0 = Abc_CountZddCubes( dd, zCover0 );
// get the ZDD of the positive polarity
bCover = Cudd_zddIsop( dd, bFuncOn, bFuncOnDc, &zCover1 );
Cudd_Ref( zCover1 );
Cudd_Ref( bCover );
Cudd_RecursiveDeref( dd, bCover );
nCubes1 = Abc_CountZddCubes( dd, zCover1 );
// compare the number of cubes
if ( nCubes1 <= nCubes0 )
{ // use positive polarity
nCubes = nCubes1;
zCover = zCover1;
Cudd_RecursiveDerefZdd( dd, zCover0 );
fPhase = 1;
}
else
{ // use negative polarity
nCubes = nCubes0;
zCover = zCover0;
Cudd_RecursiveDerefZdd( dd, zCover1 );
fPhase = 0;
}
}
else if ( fMode == 0 )
{
// get the ZDD of the negative polarity
bCover = Cudd_zddIsop( dd, Cudd_Not(bFuncOnDc), Cudd_Not(bFuncOn), &zCover );
Cudd_Ref( zCover );
Cudd_Ref( bCover );
Cudd_RecursiveDeref( dd, bCover );
nCubes = Abc_CountZddCubes( dd, zCover );
fPhase = 0;
}
else if ( fMode == 1 )
{
// get the ZDD of the positive polarity
bCover = Cudd_zddIsop( dd, bFuncOn, bFuncOnDc, &zCover );
Cudd_Ref( zCover );
Cudd_Ref( bCover );
Cudd_RecursiveDeref( dd, bCover );
nCubes = Abc_CountZddCubes( dd, zCover );
fPhase = 1;
}
else
{
assert( 0 );
}
// allocate memory for the cover
if ( pMan )
pSop = Extra_MmFlexEntryFetch( pMan, (nFanins + 3) * nCubes + 1 );
else
pSop = ALLOC( char, (nFanins + 3) * nCubes + 1 );
pSop[(nFanins + 3) * nCubes] = 0;
// create the SOP
Vec_StrFill( vCube, nFanins, '-' );
Vec_StrPush( vCube, '\0' );
Abc_ConvertZddToSop( dd, zCover, pSop, nFanins, vCube, fPhase );
Cudd_RecursiveDerefZdd( dd, zCover );
// verify
if ( fVerify )
{
bFuncNew = Abc_ConvertSopToBdd( dd, pSop, nFanins ); Cudd_Ref( bFuncNew );
if ( bFuncOn == bFuncOnDc )
{
if ( bFuncNew != bFuncOn )
printf( "Verification failed.\n" );
}
else
{
if ( !Cudd_bddLeq(dd, bFuncOn, bFuncNew) || !Cudd_bddLeq(dd, bFuncNew, bFuncOnDc) )
printf( "Verification failed.\n" );
}
Cudd_RecursiveDeref( dd, bFuncNew );
}
return pSop;
}
/**Function*************************************************************
Synopsis [Derive the SOP from the ZDD representation of the cubes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Abc_ConvertZddToSop_rec( DdManager * dd, DdNode * zCover, char * pSop, int nFanins, Vec_Str_t * vCube, int fPhase, int * pnCubes )
{
DdNode * zC0, * zC1, * zC2;
int Index;
if ( zCover == dd->zero )
return;
if ( zCover == dd->one )
{
char * pCube;
pCube = pSop + (*pnCubes) * (nFanins + 3);
sprintf( pCube, "%s %d\n", vCube->pArray, fPhase );
(*pnCubes)++;
return;
}
Index = zCover->index/2;
assert( Index < nFanins );
extraDecomposeCover( dd, zCover, &zC0, &zC1, &zC2 );
vCube->pArray[Index] = '0';
Abc_ConvertZddToSop_rec( dd, zC0, pSop, nFanins, vCube, fPhase, pnCubes );
vCube->pArray[Index] = '1';
Abc_ConvertZddToSop_rec( dd, zC1, pSop, nFanins, vCube, fPhase, pnCubes );
vCube->pArray[Index] = '-';
Abc_ConvertZddToSop_rec( dd, zC2, pSop, nFanins, vCube, fPhase, pnCubes );
}
/**Function*************************************************************
Synopsis [Derive the BDD for the function in the cut.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_ConvertZddToSop( DdManager * dd, DdNode * zCover, char * pSop, int nFanins, Vec_Str_t * vCube, int fPhase )
{
int nCubes = 0;
Abc_ConvertZddToSop_rec( dd, zCover, pSop, nFanins, vCube, fPhase, &nCubes );
return nCubes;
}
/**Function*************************************************************
Synopsis [Computes the SOPs of the negative and positive phase of the node.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Abc_NodeBddToCnf( Abc_Obj_t * pNode, Extra_MmFlex_t * pMmMan, Vec_Str_t * vCube, char ** ppSop0, char ** ppSop1 )
{
assert( Abc_NtkIsBddLogic(pNode->pNtk) );
*ppSop0 = Abc_ConvertBddToSop( pMmMan, pNode->pNtk->pManFunc, pNode->pData, pNode->pData, Abc_ObjFaninNum(pNode), vCube, 0 );
*ppSop1 = Abc_ConvertBddToSop( pMmMan, pNode->pNtk->pManFunc, pNode->pData, pNode->pData, Abc_ObjFaninNum(pNode), vCube, 1 );
}
/**Function*************************************************************
Synopsis [Count the number of paths in the ZDD.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Abc_CountZddCubes_rec( DdManager * dd, DdNode * zCover, int * pnCubes )
{
DdNode * zC0, * zC1, * zC2;
if ( zCover == dd->zero )
return;
if ( zCover == dd->one )
{
(*pnCubes)++;
return;
}
extraDecomposeCover( dd, zCover, &zC0, &zC1, &zC2 );
Abc_CountZddCubes_rec( dd, zC0, pnCubes );
Abc_CountZddCubes_rec( dd, zC1, pnCubes );
Abc_CountZddCubes_rec( dd, zC2, pnCubes );
}
/**Function*************************************************************
Synopsis [Count the number of paths in the ZDD.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_CountZddCubes( DdManager * dd, DdNode * zCover )
{
int nCubes = 0;
Abc_CountZddCubes_rec( dd, zCover, &nCubes );
return nCubes;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
|
