/**CFile****************************************************************
FileName [abcFx.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Network and node package.]
Synopsis [Implementation of traditional "fast_extract" algorithm.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - April 26, 2013.]
Revision [$Id: abcFx.c,v 1.00 2013/04/26 00:00:00 alanmi Exp $]
***********************************************************************/
#include "base/abc/abc.h"
#include "misc/vec/vecWec.h"
#include "misc/vec/vecQue.h"
#include "misc/vec/vecHsh.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
/*
The code in this file implements the traditional "fast_extract" algorithm,
which extracts two-cube divisors concurrently with single-cube two-literal divisors,
as proposed in the TCAD'92 paper by J. Rajski and J. Vasudevamurthi.
Integration notes:
It is assumed that each object (primary input or internal node) in the original network
is associated with a unique integer number, called object identifier (ObjId, for short).
The user's input data given to 'fast_extract" is an array of cubes (pMan->vCubes).
Each cube is an array of integers, in which the first entry contains ObjId of the node,
to which this cube belongs in the original network. The following entries of a cube are
SOP literals of this cube. Each literal is represtned as 2*FaninId + ComplAttr, where FaninId
is ObjId of the fanin node and ComplAttr is 1 if literal is complemented, and 0 otherwise.
The user's output data produced by 'fast_extract' is also an array of cubes (pMan->vCubes).
If no divisors have been extracted, the output array is the same as the input array.
If some divisors have been extracted, the output array contains updated old cubes and new cubes
representing the extracted divisors. The new divisors have their ObjId starting from the
largest ObjId used in the cubes. To give the user more flexibility, which may be needed when some
ObjIds are already used for primary output nodes, which do not participate in fast_extract,
the parameter ObjIdMax is passed to procedure Fx_FastExtract(). The new divisors will receive
their ObjId starting from ObjIdMax onward, as divisor extaction proceeds.
The following two requirements are imposed on the input and output array of cubes:
(1) The array of cubes should be sorted by the first entry in each cube (that is, cubes belonging
to the same node should form a contiguous range).
(2) Literals in a cube should be sorted in the increasing order of the integer numbers.
To integrate this code into a calling application, such as ABC, the input cube array should
be generated (below this is done by the procedure Abc_NtkFxRetrieve) and the output cube array
should be incorporated into the current network (below this is done by the procedure Abc_NtkFxInsert).
In essence, the latter procedure performs the following:
- removes the current fanins and SOPs of each node in the network
- adds new nodes for each new divisor introduced by "fast_extract"
- populates fanins and SOPs of each node, both old and new, as indicaded by the resulting cube array.
Implementation notes:
The implementation is optimized for simplicity and speed of computation.
(1) Main input/output data-structure (pMan->vCubes) is the array of cubes which is dynamically updated by the algorithm.
(2) Auxiliary data-structure (pMan->vLits) is the array of arrays. The i-th array contains IDs of cubes which have literal i.
It may be convenient to think about the first (second) array as rows (columns) of a sparse matrix,
although the sparse matrix data-structure is not used in the proposed implementation.
(3) Hash table (pMan->pHash) hashes the normalized divisors (represented as integer arrays) into integer numbers.
(4) Array of divisor weights (pMan->vWeights), that is, the number of SOP literals to be saved by extacting each divisor.
(5) Priority queue (pMan->vPrio), which sorts divisor (integer numbers) by their weight
(6) Integer array (pMan->vVarCube), which maps each ObjId into the first cube of this object,
or -1, if there is no cubes as in the case of a primary input.
*/
typedef struct Fx_Man_t_ Fx_Man_t;
struct Fx_Man_t_
{
// user's data
Vec_Wec_t * vCubes; // cube -> lit
int LitCountMax;// max size of divisor to extract
// internal data
Vec_Wec_t * vLits; // lit -> cube
Vec_Int_t * vCounts; // literal counts (currently not used)
Hsh_VecMan_t * pHash; // hash table for normalized divisors
Vec_Flt_t * vWeights; // divisor weights
Vec_Que_t * vPrio; // priority queue for divisors by weight
Vec_Int_t * vVarCube; // mapping ObjId into its first cube
Vec_Int_t * vLevels; // variable levels
// temporary data to update the data-structure when a divisor is extracted
Vec_Int_t * vCubesS; // single cubes for the given divisor
Vec_Int_t * vCubesD; // cube pairs for the given divisor
Vec_Int_t * vCompls; // complemented attribute of each cube pair
Vec_Int_t * vCubeFree; // cube-free divisor
Vec_Int_t * vDiv; // selected divisor
// statistics
abctime timeStart; // starting time
int nVars; // original problem variables
int nLits; // the number of SOP literals
int nDivs; // the number of extracted divisors
int nCompls; // the number of complements
int nPairsS; // number of lit pairs
int nPairsD; // number of cube pairs
int nDivsS; // single cube divisors
int nDivMux[3]; // 0 = mux, 1 = compl mux, 2 = no mux
};
static inline int Fx_ManGetFirstVarCube( Fx_Man_t * p, Vec_Int_t * vCube ) { return Vec_IntEntry( p->vVarCube, Vec_IntEntry(vCube, 0) ); }
#define Fx_ManForEachCubeVec( vVec, vCubes, vCube, i ) \
for ( i = 0; (i < Vec_IntSize(vVec)) && ((vCube) = Vec_WecEntry(vCubes, Vec_IntEntry(vVec, i))); i++ )
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Retrieves SOP information for fast_extract.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Vec_Wec_t * Abc_NtkFxRetrieve( Abc_Ntk_t * pNtk )
{
Vec_Wec_t * vCubes;
Vec_Int_t * vCube;
Abc_Obj_t * pNode;
char * pCube, * pSop;
int nVars, i, v, Lit;
assert( Abc_NtkIsSopLogic(pNtk) );
vCubes = Vec_WecAlloc( 1000 );
Abc_NtkForEachNode( pNtk, pNode, i )
{
pSop = (char *)pNode->pData;
nVars = Abc_SopGetVarNum(pSop);
assert( nVars == Abc_ObjFaninNum(pNode) );
// if ( nVars < 2 ) continue;
Abc_SopForEachCube( pSop, nVars, pCube )
{
vCube = Vec_WecPushLevel( vCubes );
Vec_IntPush( vCube, Abc_ObjId(pNode) );
Abc_CubeForEachVar( pCube, Lit, v )
{
if ( Lit == '0' )
Vec_IntPush( vCube, Abc_Var2Lit(Abc_ObjFaninId(pNode, v), 1) );
else if ( Lit == '1' )
Vec_IntPush( vCube, Abc_Var2Lit(Abc_ObjFaninId(pNode, v), 0) );
}
Vec_IntSelectSort( Vec_IntArray(vCube) + 1, Vec_IntSize(vCube) - 1 );
}
}
return vCubes;
}
/**Function*************************************************************
Synopsis [Inserts SOP information after fast_extract.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Abc_NtkFxInsert( Abc_Ntk_t * pNtk, Vec_Wec_t * vCubes )
{
Vec_Int_t * vCube, * vPres, * vFirst, * vCount;
Abc_Obj_t * pNode, * pFanin;
char * pCube, * pSop;
int i, k, v, Lit, iFanin, iNodeMax = 0;
assert( Abc_NtkIsSopLogic(pNtk) );
// check that cubes have no gaps and are ordered by first node
Lit = -1;
Vec_WecForEachLevel( vCubes, vCube, i )
{
assert( Vec_IntSize(vCube) > 0 );
assert( Lit <= Vec_IntEntry(vCube, 0) );
Lit = Vec_IntEntry(vCube, 0);
}
// find the largest index
Vec_WecForEachLevel( vCubes, vCube, i )
iNodeMax = Abc_MaxInt( iNodeMax, Vec_IntEntry(vCube, 0) );
// quit if nothing changes
if ( iNodeMax < Abc_NtkObjNumMax(pNtk) )
{
printf( "The network is unchanged by fast extract.\n" );
return;
}
// create new nodes
for ( i = Abc_NtkObjNumMax(pNtk); i <= iNodeMax; i++ )
{
pNode = Abc_NtkCreateNode( pNtk );
assert( i == (int)Abc_ObjId(pNode) );
}
// create node fanins
vFirst = Vec_IntStart( Abc_NtkObjNumMax(pNtk) );
vCount = Vec_IntStart( Abc_NtkObjNumMax(pNtk) );
Vec_WecForEachLevel( vCubes, vCube, i )
{
iFanin = Vec_IntEntry( vCube, 0 );
if ( Vec_IntEntry(vCount, iFanin) == 0 )
Vec_IntWriteEntry( vFirst, iFanin, i );
Vec_IntAddToEntry( vCount, iFanin, 1 );
}
// create node SOPs
vPres = Vec_IntStartFull( Abc_NtkObjNumMax(pNtk) );
Abc_NtkForEachNode( pNtk, pNode, i )
{
// if ( Vec_IntEntry(vCount, i) == 0 ) continue;
Abc_ObjRemoveFanins( pNode );
// create fanins
assert( Vec_IntEntry(vCount, i) > 0 );
for ( k = 0; k < Vec_IntEntry(vCount, i); k++ )
{
vCube = Vec_WecEntry( vCubes, Vec_IntEntry(vFirst, i) + k );
assert( Vec_IntEntry( vCube, 0 ) == i );
Vec_IntForEachEntryStart( vCube, Lit, v, 1 )
{
pFanin = Abc_NtkObj(pNtk, Abc_Lit2Var(Lit));
if ( Vec_IntEntry(vPres, Abc_ObjId(pFanin)) >= 0 )
continue;
Vec_IntWriteEntry(vPres, Abc_ObjId(pFanin), Abc_ObjFaninNum(pNode));
Abc_ObjAddFanin( pNode, pFanin );
}
}
// create SOP
pSop = pCube = Abc_SopStart( (Mem_Flex_t *)pNtk->pManFunc, Vec_IntEntry(vCount, i), Abc_ObjFaninNum(pNode) );
for ( k = 0; k < Vec_IntEntry(vCount, i); k++ )
{
vCube = Vec_WecEntry( vCubes, Vec_IntEntry(vFirst, i) + k );
assert( Vec_IntEntry( vCube, 0 ) == i );
Vec_IntForEachEntryStart( vCube, Lit, v, 1 )
{
pFanin = Abc_NtkObj(pNtk, Abc_Lit2Var(Lit));
iFanin = Vec_IntEntry(vPres, Abc_ObjId(pFanin));
assert( iFanin >= 0 && iFanin < Abc_ObjFaninNum(pNode) );
pCube[iFanin] = Abc_LitIsCompl(Lit) ? '0' : '1';
}
pCube += Abc_ObjFaninNum(pNode) + 3;
}
// complement SOP if the original one was complemented
if ( pNode->pData && Abc_SopIsComplement((char *)pNode->pData) )
Abc_SopComplement( pSop );
pNode->pData = pSop;
// clean fanins
Abc_ObjForEachFanin( pNode, pFanin, v )
Vec_IntWriteEntry( vPres, Abc_ObjId(pFanin), -1 );
}
Vec_IntFree( vFirst );
Vec_IntFree( vCount );
Vec_IntFree( vPres );
}
/**Function*************************************************************
Synopsis [Makes sure the nodes do not have complemented and duplicated fanins.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_NtkFxCheck( Abc_Ntk_t * pNtk )
{
Abc_Obj_t * pNode;
int i;
// Abc_NtkForEachObj( pNtk, pNode, i )
// Abc_ObjPrint( stdout, pNode );
Abc_NtkForEachNode( pNtk, pNode, i )
if ( !Vec_IntCheckUniqueSmall( &pNode->vFanins ) )
return 0;
return 1;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_NtkFxPerform( Abc_Ntk_t * pNtk, int nNewNodesMax, int LitCountMax, int fVerbose, int fVeryVerbose )
{
extern int Fx_FastExtract( Vec_Wec_t * vCubes, int ObjIdMax, int nNewNodesMax, int LitCountMax, int fVerbose, int fVeryVerbose );
Vec_Wec_t * vCubes;
assert( Abc_NtkIsSopLogic(pNtk) );
// check unique fanins
if ( !Abc_NtkFxCheck(pNtk) )
{
printf( "Abc_NtkFastExtract: Nodes have duplicated fanins. FX is not performed.\n" );
return 0;
}
// sweep removes useless nodes
Abc_NtkCleanup( pNtk, 0 );
// Abc_NtkOrderFanins( pNtk );
// makes sure the SOPs are SCC-free and D1C-free
Abc_NtkMakeLegit( pNtk );
// collect information about the covers
vCubes = Abc_NtkFxRetrieve( pNtk );
// call the fast extract procedure
if ( Fx_FastExtract( vCubes, Abc_NtkObjNumMax(pNtk), nNewNodesMax, LitCountMax, fVerbose, fVeryVerbose ) > 0 )
{
// update the network
Abc_NtkFxInsert( pNtk, vCubes );
Vec_WecFree( vCubes );
if ( !Abc_NtkCheck( pNtk ) )
printf( "Abc_NtkFxPerform: The network check has failed.\n" );
return 1;
}
else
printf( "Warning: The network has not been changed by \"fx\".\n" );
Vec_WecFree( vCubes );
return 0;
}
/**Function*************************************************************
Synopsis [Starting the manager.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Fx_Man_t * Fx_ManStart( Vec_Wec_t * vCubes )
{
Fx_Man_t * p;
p = ABC_CALLOC( Fx_Man_t, 1 );
p->vCubes = vCubes;
// temporary data
p->vCubesS = Vec_IntAlloc( 100 );
p->vCubesD = Vec_IntAlloc( 100 );
p->vCompls = Vec_IntAlloc( 100 );
p->vCubeFree = Vec_IntAlloc( 100 );
p->vDiv = Vec_IntAlloc( 100 );
return p;
}
void Fx_ManStop( Fx_Man_t * p )
{
// Vec_WecFree( p->vCubes );
Vec_WecFree( p->vLits );
Vec_IntFree( p->vCounts );
Hsh_VecManStop( p->pHash );
Vec_FltFree( p->vWeights );
Vec_QueFree( p->vPrio );
Vec_IntFree( p->vVarCube );
Vec_IntFree( p->vLevels );
// temporary data
Vec_IntFree( p->vCubesS );
Vec_IntFree( p->vCubesD );
Vec_IntFree( p->vCompls );
Vec_IntFree( p->vCubeFree );
Vec_IntFree( p->vDiv );
ABC_FREE( p );
}
/**Function*************************************************************
Synopsis [Compute levels of the nodes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline int Fx_ManComputeLevelDiv( Fx_Man_t * p, Vec_Int_t * vCubeFree )
{
int i, Lit, Level = 0;
Vec_IntForEachEntry( vCubeFree, Lit, i )
Level = Abc_MaxInt( Level, Vec_IntEntry(p->vLevels, Abc_Lit2Var(Abc_Lit2Var(Lit))) );
return Abc_MinInt( Level, 800 );
}
static inline int Fx_ManComputeLevelCube( Fx_Man_t * p, Vec_Int_t * vCube )
{
int k, Lit, Level = 0;
Vec_IntForEachEntryStart( vCube, Lit, k, 1 )
Level = Abc_MaxInt( Level, Vec_IntEntry(p->vLevels, Abc_Lit2Var(Lit)) );
return Level;
}
void Fx_ManComputeLevel( Fx_Man_t * p )
{
Vec_Int_t * vCube;
int i, iVar, iFirst = 0;
iVar = Vec_IntEntry( Vec_WecEntry(p->vCubes,0), 0 );
p->vLevels = Vec_IntStart( p->nVars );
Vec_WecForEachLevel( p->vCubes, vCube, i )
{
if ( iVar != Vec_IntEntry(vCube, 0) )
{
// add the number of cubes
Vec_IntAddToEntry( p->vLevels, iVar, i - iFirst );
iVar = Vec_IntEntry(vCube, 0);
iFirst = i;
}
Vec_IntUpdateEntry( p->vLevels, iVar, Fx_ManComputeLevelCube(p, vCube) );
}
}
/**Function*************************************************************
Synopsis [Printing procedures.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline char Fx_PrintDivLit( int Lit ) { return (Abc_LitIsCompl(Lit) ? 'A' : 'a') + Abc_Lit2Var(Lit); }
static inline void Fx_PrintDivOneReal( Vec_Int_t * vDiv )
{
int i, Lit;
Vec_IntForEachEntry( vDiv, Lit, i )
if ( !Abc_LitIsCompl(Lit) )
printf( "%c", Fx_PrintDivLit(Abc_Lit2Var(Lit)) );
printf( " + " );
Vec_IntForEachEntry( vDiv, Lit, i )
if ( Abc_LitIsCompl(Lit) )
printf( "%c", Fx_PrintDivLit(Abc_Lit2Var(Lit)) );
}
static inline void Fx_PrintDivOne( Vec_Int_t * vDiv )
{
int i, Lit;
Vec_IntForEachEntry( vDiv, Lit, i )
if ( !Abc_LitIsCompl(Lit) )
printf( "%c", Fx_PrintDivLit( Abc_Var2Lit(i, Abc_LitIsCompl(Lit)) ) );
printf( " + " );
Vec_IntForEachEntry( vDiv, Lit, i )
if ( Abc_LitIsCompl(Lit) )
printf( "%c", Fx_PrintDivLit( Abc_Var2Lit(i, Abc_LitIsCompl(Lit)) ) );
}
static inline void Fx_PrintDivArray( Vec_Int_t * vDiv )
{
int i, Lit;
Vec_IntForEachEntry( vDiv, Lit, i )
if ( !Abc_LitIsCompl(Lit) )
printf( "%d(1) ", Abc_Lit2Var(Lit) );
printf( " + " );
Vec_IntForEachEntry( vDiv, Lit, i )
if ( Abc_LitIsCompl(Lit) )
printf( "%d(2) ", Abc_Lit2Var(Lit) );
}
static inline void Fx_PrintDiv( Fx_Man_t * p, int iDiv )
{
int i;
printf( "%4d : ", p->nDivs );
printf( "Div %7d : ", iDiv );
printf( "Weight %12.5f ", Vec_FltEntry(p->vWeights, iDiv) );
// printf( "Compl %4d ", p->nCompls );
Fx_PrintDivOne( Hsh_VecReadEntry(p->pHash, iDiv) );
for ( i = Vec_IntSize(Hsh_VecReadEntry(p->pHash, iDiv)) + 3; i < 16; i++ )
printf( " " );
printf( "Lits =%7d ", p->nLits );
printf( "Divs =%8d ", Hsh_VecSize(p->pHash) );
Abc_PrintTime( 1, "Time", Abc_Clock() - p->timeStart );
}
static void Fx_PrintDivisors( Fx_Man_t * p )
{
int iDiv;
for ( iDiv = 0; iDiv < Vec_FltSize(p->vWeights); iDiv++ )
Fx_PrintDiv( p, iDiv );
}
static void Fx_PrintLiterals( Fx_Man_t * p )
{
Vec_Int_t * vTemp;
int i;
Vec_WecForEachLevel( p->vLits, vTemp, i )
{
printf( "%c : ", Fx_PrintDivLit(i) );
Vec_IntPrint( vTemp );
}
}
static void Fx_PrintMatrix( Fx_Man_t * p )
{
Vec_Int_t * vCube;
int i, v, Lit, nObjs;
char * pLine;
if ( Vec_WecSize(p->vLits)/2 > 26 )
return;
printf( " " );
nObjs = Vec_WecSize(p->vLits)/2;
for ( i = 0; i < Abc_MinInt(nObjs, 26); i++ )
printf( "%c", 'a' + i );
printf( "\n" );
pLine = ABC_CALLOC( char, nObjs+1 );
Vec_WecForEachLevel( p->vCubes, vCube, i )
{
if ( Vec_IntSize(vCube) == 0 )
continue;
memset( pLine, '-', nObjs );
Vec_IntForEachEntryStart( vCube, Lit, v, 1 )
{
assert( Abc_Lit2Var(Lit) < nObjs );
pLine[Abc_Lit2Var(Lit)] = Abc_LitIsCompl(Lit) ? '0' : '1';
}
printf( "%6d : %s %4d\n", i, pLine, Vec_IntEntry(vCube, 0) );
}
ABC_FREE( pLine );
Fx_PrintLiterals( p );
Fx_PrintDivisors( p );
}
static void Fx_PrintStats( Fx_Man_t * p, abctime clk )
{
printf( "Cubes =%8d ", Vec_WecSizeUsed(p->vCubes) );
printf( "Lits =%8d ", Vec_WecSizeUsed(p->vLits) );
printf( "Divs =%8d ", Hsh_VecSize(p->pHash) );
printf( "Divs+ =%8d ", Vec_QueSize(p->vPrio) );
printf( "Compl =%8d ", p->nDivMux[1] );
printf( "Extr =%7d ", p->nDivs );
// printf( "DivsS =%6d ", p->nDivsS );
// printf( "PairS =%6d ", p->nPairsS );
// printf( "PairD =%6d ", p->nPairsD );
Abc_PrintTime( 1, "Time", clk );
// printf( "\n" );
}
/**Function*************************************************************
Synopsis [Returns 1 if the divisor should be complemented.]
Description [Normalizes the divisor by putting, first, positive control
literal first and, second, positive data1 literal. As the result,
a MUX divisor is (ab + !ac) and an XOR divisor is (ab + !a!b).]
SideEffects []
SeeAlso []
***********************************************************************/
static int Fx_ManDivNormalize( Vec_Int_t * vCubeFree ) // return 1 if complemented
{
int * L = Vec_IntArray(vCubeFree);
int RetValue = 0, LitA0 = -1, LitB0 = -1, LitA1 = -1, LitB1 = -1;
assert( Vec_IntSize(vCubeFree) == 4 );
if ( Abc_LitIsCompl(L[0]) != Abc_LitIsCompl(L[1]) && (L[0] >> 2) == (L[1] >> 2) ) // diff cubes, same vars
{
if ( Abc_LitIsCompl(L[2]) == Abc_LitIsCompl(L[3]) )
return -1;
LitA0 = Abc_Lit2Var(L[0]), LitB0 = Abc_Lit2Var(L[1]);
if ( Abc_LitIsCompl(L[0]) == Abc_LitIsCompl(L[2]) )
{
assert( Abc_LitIsCompl(L[1]) == Abc_LitIsCompl(L[3]) );
LitA1 = Abc_Lit2Var(L[2]), LitB1 = Abc_Lit2Var(L[3]);
}
else
{
assert( Abc_LitIsCompl(L[0]) == Abc_LitIsCompl(L[3]) );
assert( Abc_LitIsCompl(L[1]) == Abc_LitIsCompl(L[2]) );
LitA1 = Abc_Lit2Var(L[3]), LitB1 = Abc_Lit2Var(L[2]);
}
}
else if ( Abc_LitIsCompl(L[1]) != Abc_LitIsCompl(L[2]) && (L[1] >> 2) == (L[2] >> 2) )
{
if ( Abc_LitIsCompl(L[0]) == Abc_LitIsCompl(L[3]) )
return -1;
LitA0 = Abc_Lit2Var(L[1]), LitB0 = Abc_Lit2Var(L[2]);
if ( Abc_LitIsCompl(L[1]) == Abc_LitIsCompl(L[0]) )
LitA1 = Abc_Lit2Var(L[0]), LitB1 = Abc_Lit2Var(L[3]);
else
LitA1 = Abc_Lit2Var(L[3]), LitB1 = Abc_Lit2Var(L[0]);
}
else if ( Abc_LitIsCompl(L[2]) != Abc_LitIsCompl(L[3]) && (L[2] >> 2) == (L[3] >> 2) )
{
if ( Abc_LitIsCompl(L[0]) == Abc_LitIsCompl(L[1]) )
return -1;
LitA0 = Abc_Lit2Var(L[2]), LitB0 = Abc_Lit2Var(L[3]);
if ( Abc_LitIsCompl(L[2]) == Abc_LitIsCompl(L[0]) )
LitA1 = Abc_Lit2Var(L[0]), LitB1 = Abc_Lit2Var(L[1]);
else
LitA1 = Abc_Lit2Var(L[1]), LitB1 = Abc_Lit2Var(L[0]);
}
else
return -1;
assert( LitA0 == Abc_LitNot(LitB0) );
if ( Abc_LitIsCompl(LitA0) )
{
ABC_SWAP( int, LitA0, LitB0 );
ABC_SWAP( int, LitA1, LitB1 );
}
assert( !Abc_LitIsCompl(LitA0) );
if ( Abc_LitIsCompl(LitA1) )
{
LitA1 = Abc_LitNot(LitA1);
LitB1 = Abc_LitNot(LitB1);
RetValue = 1;
}
assert( !Abc_LitIsCompl(LitA1) );
// arrange literals in such as a way that
// - the first two literals are control literals from different cubes
// - the third literal is non-complented data input
// - the forth literal is possibly complemented data input
L[0] = Abc_Var2Lit( LitA0, 0 );
L[1] = Abc_Var2Lit( LitB0, 1 );
L[2] = Abc_Var2Lit( LitA1, 0 );
L[3] = Abc_Var2Lit( LitB1, 1 );
return RetValue;
}
/**Function*************************************************************
Synopsis [Find a cube-free divisor of the two cubes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Fx_ManDivFindCubeFree( Vec_Int_t * vArr1, Vec_Int_t * vArr2, Vec_Int_t * vCubeFree )
{
int * pBeg1 = vArr1->pArray + 1; // skip variable ID
int * pBeg2 = vArr2->pArray + 1; // skip variable ID
int * pEnd1 = vArr1->pArray + vArr1->nSize;
int * pEnd2 = vArr2->pArray + vArr2->nSize;
int Counter = 0, fAttr0 = 0, fAttr1 = 1;
Vec_IntClear( vCubeFree );
while ( pBeg1 < pEnd1 && pBeg2 < pEnd2 )
{
if ( *pBeg1 == *pBeg2 )
pBeg1++, pBeg2++, Counter++;
else if ( *pBeg1 < *pBeg2 )
Vec_IntPush( vCubeFree, Abc_Var2Lit(*pBeg1++, fAttr0) );
else
{
if ( Vec_IntSize(vCubeFree) == 0 )
fAttr0 = 1, fAttr1 = 0;
Vec_IntPush( vCubeFree, Abc_Var2Lit(*pBeg2++, fAttr1) );
}
}
while ( pBeg1 < pEnd1 )
Vec_IntPush( vCubeFree, Abc_Var2Lit(*pBeg1++, fAttr0) );
while ( pBeg2 < pEnd2 )
Vec_IntPush( vCubeFree, Abc_Var2Lit(*pBeg2++, fAttr1) );
if ( Vec_IntSize(vCubeFree) == 0 )
printf( "The SOP has duplicated cubes.\n" );
else if ( Vec_IntSize(vCubeFree) == 1 )
printf( "The SOP has contained cubes.\n" );
else if ( Vec_IntSize(vCubeFree) == 2 && Abc_Lit2Var(Abc_Lit2Var(Vec_IntEntry(vCubeFree, 0))) == Abc_Lit2Var(Abc_Lit2Var(Vec_IntEntry(vCubeFree, 1))) )
printf( "The SOP has distance-1 cubes or it is not a prime cover. Please make sure the result verifies.\n" );
assert( !Abc_LitIsCompl(Vec_IntEntry(vCubeFree, 0)) );
return Counter;
}
/**Function*************************************************************
Synopsis [Procedures operating on a two-cube divisor.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline void Fx_ManDivFindPivots( Vec_Int_t * vDiv, int * pLit0, int * pLit1 )
{
int i, Lit;
*pLit0 = -1;
*pLit1 = -1;
Vec_IntForEachEntry( vDiv, Lit, i )
{
if ( Abc_LitIsCompl(Lit) )
{
if ( *pLit1 == -1 )
*pLit1 = Abc_Lit2Var(Lit);
}
else
{
if ( *pLit0 == -1 )
*pLit0 = Abc_Lit2Var(Lit);
}
if ( *pLit0 >= 0 && *pLit1 >= 0 )
return;
}
}
static inline int Fx_ManDivRemoveLits( Vec_Int_t * vCube, Vec_Int_t * vDiv, int fCompl )
{
int i, Lit, Count = 0;
assert( !fCompl || Vec_IntSize(vDiv) == 4 );
Vec_IntForEachEntry( vDiv, Lit, i )
Count += Vec_IntRemove1( vCube, Abc_Lit2Var(Lit) ^ (fCompl && i > 1) ); // the last two lits can be complemented
return Count;
}
static inline void Fx_ManDivAddLits( Vec_Int_t * vCube, Vec_Int_t * vCube2, Vec_Int_t * vDiv )
{
int i, Lit, * pArray;
// Vec_IntClear( vCube );
// Vec_IntClear( vCube2 );
Vec_IntForEachEntry( vDiv, Lit, i )
if ( Abc_LitIsCompl(Lit) )
Vec_IntPush( vCube2, Abc_Lit2Var(Lit) );
else
Vec_IntPush( vCube, Abc_Lit2Var(Lit) );
if ( Vec_IntSize(vDiv) == 4 && Vec_IntSize(vCube) == 3 )
{
assert( Vec_IntSize(vCube2) == 3 );
pArray = Vec_IntArray(vCube);
if ( pArray[1] > pArray[2] )
ABC_SWAP( int, pArray[1], pArray[2] );
pArray = Vec_IntArray(vCube2);
if ( pArray[1] > pArray[2] )
ABC_SWAP( int, pArray[1], pArray[2] );
}
}
/**Function*************************************************************
Synopsis [Setting up the data-structure.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Fx_ManCreateLiterals( Fx_Man_t * p, int nVars )
{
Vec_Int_t * vCube;
int i, k, Lit, Count;
// find the number of variables
p->nVars = p->nLits = 0;
Vec_WecForEachLevel( p->vCubes, vCube, i )
{
assert( Vec_IntSize(vCube) > 0 );
p->nVars = Abc_MaxInt( p->nVars, Vec_IntEntry(vCube, 0) );
p->nLits += Vec_IntSize(vCube) - 1;
Vec_IntForEachEntryStart( vCube, Lit, k, 1 )
p->nVars = Abc_MaxInt( p->nVars, Abc_Lit2Var(Lit) );
}
// p->nVars++;
assert( p->nVars < nVars );
p->nVars = nVars;
// count literals
p->vCounts = Vec_IntStart( 2*p->nVars );
Vec_WecForEachLevel( p->vCubes, vCube, i )
Vec_IntForEachEntryStart( vCube, Lit, k, 1 )
Vec_IntAddToEntry( p->vCounts, Lit, 1 );
// start literals
p->vLits = Vec_WecStart( 2*p->nVars );
Vec_IntForEachEntry( p->vCounts, Count, Lit )
Vec_IntGrow( Vec_WecEntry(p->vLits, Lit), Count );
// fill out literals
Vec_WecForEachLevel( p->vCubes, vCube, i )
Vec_IntForEachEntryStart( vCube, Lit, k, 1 )
Vec_WecPush( p->vLits, Lit, i );
// create mapping of variable into the first cube
p->vVarCube = Vec_IntStartFull( p->nVars );
Vec_WecForEachLevel( p->vCubes, vCube, i )
if ( Vec_IntEntry(p->vVarCube, Vec_IntEntry(vCube, 0)) == -1 )
Vec_IntWriteEntry( p->vVarCube, Vec_IntEntry(vCube, 0), i );
}
int Fx_ManCubeSingleCubeDivisors( Fx_Man_t * p, Vec_Int_t * vPivot, int fRemove, int fUpdate )
{
int k, n, Lit, Lit2, iDiv;
if ( Vec_IntSize(vPivot) < 2 )
return 0;
Vec_IntForEachEntryStart( vPivot, Lit, k, 1 )
Vec_IntForEachEntryStart( vPivot, Lit2, n, k+1 )
{
assert( Lit < Lit2 );
Vec_IntClear( p->vCubeFree );
Vec_IntPush( p->vCubeFree, Abc_Var2Lit(Abc_LitNot(Lit), 0) );
Vec_IntPush( p->vCubeFree, Abc_Var2Lit(Abc_LitNot(Lit2), 1) );
iDiv = Hsh_VecManAdd( p->pHash, p->vCubeFree );
if ( !fRemove )
{
if ( Vec_FltSize(p->vWeights) == iDiv )
{
Vec_FltPush(p->vWeights, -2 + 0.9 - 0.001 * Fx_ManComputeLevelDiv(p, p->vCubeFree));
p->nDivsS++;
}
assert( iDiv < Vec_FltSize(p->vWeights) );
Vec_FltAddToEntry( p->vWeights, iDiv, 1 );
p->nPairsS++;
}
else
{
assert( iDiv < Vec_FltSize(p->vWeights) );
Vec_FltAddToEntry( p->vWeights, iDiv, -1 );
p->nPairsS--;
}
if ( fUpdate )
{
if ( Vec_QueIsMember(p->vPrio, iDiv) )
Vec_QueUpdate( p->vPrio, iDiv );
else if ( !fRemove )
Vec_QuePush( p->vPrio, iDiv );
}
}
return Vec_IntSize(vPivot) * (Vec_IntSize(vPivot) - 1) / 2;
}
void Fx_ManCubeDoubleCubeDivisors( Fx_Man_t * p, int iFirst, Vec_Int_t * vPivot, int fRemove, int fUpdate )
{
Vec_Int_t * vCube;
int i, iDiv, Base;
Vec_WecForEachLevelStart( p->vCubes, vCube, i, iFirst )
{
if ( Vec_IntSize(vCube) == 0 || vCube == vPivot )
continue;
if ( Vec_WecIntHasMark(vCube) && Vec_WecIntHasMark(vPivot) && vCube > vPivot )
continue;
if ( Vec_IntEntry(vCube, 0) != Vec_IntEntry(vPivot, 0) )
break;
Base = Fx_ManDivFindCubeFree( vCube, vPivot, p->vCubeFree );
if ( Vec_IntSize(p->vCubeFree) == 4 )
{
int Value = Fx_ManDivNormalize( p->vCubeFree );
if ( Value == 0 )
p->nDivMux[0]++;
else if ( Value == 1 )
p->nDivMux[1]++;
else
p->nDivMux[2]++;
}
if ( p->LitCountMax && p->LitCountMax < Vec_IntSize(p->vCubeFree) )
continue;
iDiv = Hsh_VecManAdd( p->pHash, p->vCubeFree );
if ( !fRemove )
{
if ( iDiv == Vec_FltSize(p->vWeights) )
Vec_FltPush(p->vWeights, -Vec_IntSize(p->vCubeFree) + 0.9 - 0.0009 * Fx_ManComputeLevelDiv(p, p->vCubeFree));
assert( iDiv < Vec_FltSize(p->vWeights) );
Vec_FltAddToEntry( p->vWeights, iDiv, Base + Vec_IntSize(p->vCubeFree) - 1 );
p->nPairsD++;
}
else
{
assert( iDiv < Vec_FltSize(p->vWeights) );
Vec_FltAddToEntry( p->vWeights, iDiv, -(Base + Vec_IntSize(p->vCubeFree) - 1) );
p->nPairsD--;
}
if ( fUpdate )
{
if ( Vec_QueIsMember(p->vPrio, iDiv) )
Vec_QueUpdate( p->vPrio, iDiv );
else if ( !fRemove )
Vec_QuePush( p->vPrio, iDiv );
}
}
}
void Fx_ManCreateDivisors( Fx_Man_t * p )
{
Vec_Int_t * vCube;
float Weight;
int i;
// alloc hash table
assert( p->pHash == NULL );
p->pHash = Hsh_VecManStart( 1000 );
p->vWeights = Vec_FltAlloc( 1000 );
// create single-cube two-literal divisors
Vec_WecForEachLevel( p->vCubes, vCube, i )
Fx_ManCubeSingleCubeDivisors( p, vCube, 0, 0 ); // add - no update
assert( p->nDivsS == Vec_FltSize(p->vWeights) );
// create two-cube divisors
Vec_WecForEachLevel( p->vCubes, vCube, i )
Fx_ManCubeDoubleCubeDivisors( p, i+1, vCube, 0, 0 ); // add - no update
// create queue with all divisors
p->vPrio = Vec_QueAlloc( Vec_FltSize(p->vWeights) );
Vec_QueSetPriority( p->vPrio, Vec_FltArrayP(p->vWeights) );
Vec_FltForEachEntry( p->vWeights, Weight, i )
if ( Weight > 0.0 )
Vec_QuePush( p->vPrio, i );
}
/**Function*************************************************************
Synopsis [Compress the cubes by removing unused ones.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline void Fx_ManCompressCubes( Vec_Wec_t * vCubes, Vec_Int_t * vLit2Cube )
{
int i, CubeId, k = 0;
Vec_IntForEachEntry( vLit2Cube, CubeId, i )
if ( Vec_IntSize(Vec_WecEntry(vCubes, CubeId)) > 0 )
Vec_IntWriteEntry( vLit2Cube, k++, CubeId );
Vec_IntShrink( vLit2Cube, k );
}
/**Function*************************************************************
Synopsis [Find command cube pairs.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline int Fx_ManGetCubeVar( Vec_Wec_t * vCubes, int iCube ) { return Vec_IntEntry( Vec_WecEntry(vCubes, iCube), 0 ); }
void Fx_ManFindCommonPairs( Vec_Wec_t * vCubes, Vec_Int_t * vPart0, Vec_Int_t * vPart1, Vec_Int_t * vPairs, Vec_Int_t * vCompls, Vec_Int_t * vDiv, Vec_Int_t * vCubeFree )
{
int * pBeg1 = vPart0->pArray;
int * pBeg2 = vPart1->pArray;
int * pEnd1 = vPart0->pArray + vPart0->nSize;
int * pEnd2 = vPart1->pArray + vPart1->nSize;
int i, k, i_, k_, fCompl, CubeId1, CubeId2;
Vec_IntClear( vPairs );
Vec_IntClear( vCompls );
while ( pBeg1 < pEnd1 && pBeg2 < pEnd2 )
{
CubeId1 = Fx_ManGetCubeVar(vCubes, *pBeg1);
CubeId2 = Fx_ManGetCubeVar(vCubes, *pBeg2);
if ( CubeId1 == CubeId2 )
{
for ( i = 1; pBeg1+i < pEnd1; i++ )
if ( CubeId1 != Fx_ManGetCubeVar(vCubes, pBeg1[i]) )
break;
for ( k = 1; pBeg2+k < pEnd2; k++ )
if ( CubeId1 != Fx_ManGetCubeVar(vCubes, pBeg2[k]) )
break;
for ( i_ = 0; i_ < i; i_++ )
for ( k_ = 0; k_ < k; k_++ )
{
if ( pBeg1[i_] == pBeg2[k_] )
continue;
Fx_ManDivFindCubeFree( Vec_WecEntry(vCubes, pBeg1[i_]), Vec_WecEntry(vCubes, pBeg2[k_]), vCubeFree );
fCompl = (Vec_IntSize(vCubeFree) == 4 && Fx_ManDivNormalize(vCubeFree) == 1);
if ( !Vec_IntEqual( vDiv, vCubeFree ) )
continue;
Vec_IntPush( vPairs, pBeg1[i_] );
Vec_IntPush( vPairs, pBeg2[k_] );
Vec_IntPush( vCompls, fCompl );
}
pBeg1 += i;
pBeg2 += k;
}
else if ( CubeId1 < CubeId2 )
pBeg1++;
else
pBeg2++;
}
}
/**Function*************************************************************
Synopsis [Updates the data-structure when one divisor is selected.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Fx_ManUpdate( Fx_Man_t * p, int iDiv )
{
Vec_Int_t * vCube, * vCube2, * vLitP, * vLitN;
Vec_Int_t * vDiv = p->vDiv;
int nLitsNew = p->nLits - (int)Vec_FltEntry(p->vWeights, iDiv);
int i, k, Lit0, Lit1, iVarNew, RetValue, Level;
float Diff = Vec_FltEntry(p->vWeights, iDiv) - (float)((int)Vec_FltEntry(p->vWeights, iDiv));
assert( Diff > 0.0 && Diff < 1.0 );
// get the divisor and select pivot variables
p->nDivs++;
Vec_IntClear( vDiv );
Vec_IntAppend( vDiv, Hsh_VecReadEntry(p->pHash, iDiv) );
Fx_ManDivFindPivots( vDiv, &Lit0, &Lit1 );
assert( Lit0 >= 0 && Lit1 >= 0 );
// if the input cover is not prime, it may happen that we are extracting divisor (x + !x)
// although it is not strictly correct, it seems to be fine to just skip such divisors
if ( Abc_Lit2Var(Lit0) == Abc_Lit2Var(Lit1) && Vec_IntSize(Hsh_VecReadEntry(p->pHash, iDiv)) == 2 )
return;
// collect single-cube-divisor cubes
Vec_IntClear( p->vCubesS );
if ( Vec_IntSize(vDiv) == 2 )
{
Fx_ManCompressCubes( p->vCubes, Vec_WecEntry(p->vLits, Abc_LitNot(Lit0)) );
Fx_ManCompressCubes( p->vCubes, Vec_WecEntry(p->vLits, Abc_LitNot(Lit1)) );
Vec_IntTwoRemoveCommon( Vec_WecEntry(p->vLits, Abc_LitNot(Lit0)), Vec_WecEntry(p->vLits, Abc_LitNot(Lit1)), p->vCubesS );
}
// collect double-cube-divisor cube pairs
Fx_ManCompressCubes( p->vCubes, Vec_WecEntry(p->vLits, Lit0) );
Fx_ManCompressCubes( p->vCubes, Vec_WecEntry(p->vLits, Lit1) );
Fx_ManFindCommonPairs( p->vCubes, Vec_WecEntry(p->vLits, Lit0), Vec_WecEntry(p->vLits, Lit1), p->vCubesD, p->vCompls, vDiv, p->vCubeFree );
// subtract cost of single-cube divisors
Fx_ManForEachCubeVec( p->vCubesS, p->vCubes, vCube, i )
Fx_ManCubeSingleCubeDivisors( p, vCube, 1, 1 ); // remove - update
Fx_ManForEachCubeVec( p->vCubesD, p->vCubes, vCube, i )
Fx_ManCubeSingleCubeDivisors( p, vCube, 1, 1 ); // remove - update
// mark the cubes to be removed
Vec_WecMarkLevels( p->vCubes, p->vCubesS );
Vec_WecMarkLevels( p->vCubes, p->vCubesD );
// subtract cost of double-cube divisors
Fx_ManForEachCubeVec( p->vCubesS, p->vCubes, vCube, i )
Fx_ManCubeDoubleCubeDivisors( p, Fx_ManGetFirstVarCube(p, vCube), vCube, 1, 1 ); // remove - update
Fx_ManForEachCubeVec( p->vCubesD, p->vCubes, vCube, i )
Fx_ManCubeDoubleCubeDivisors( p, Fx_ManGetFirstVarCube(p, vCube), vCube, 1, 1 ); // remove - update
// unmark the cubes to be removed
Vec_WecUnmarkLevels( p->vCubes, p->vCubesS );
Vec_WecUnmarkLevels( p->vCubes, p->vCubesD );
// create new divisor
iVarNew = Vec_WecSize( p->vLits ) / 2;
assert( Vec_IntSize(p->vVarCube) == iVarNew );
Vec_IntPush( p->vVarCube, Vec_WecSize(p->vCubes) );
vCube = Vec_WecPushLevel( p->vCubes );
Vec_IntPush( vCube, iVarNew );
if ( Vec_IntSize(vDiv) == 2 )
{
Vec_IntPush( vCube, Abc_LitNot(Lit0) );
Vec_IntPush( vCube, Abc_LitNot(Lit1) );
Level = 1 + Fx_ManComputeLevelCube( p, vCube );
}
else
{
vCube2 = Vec_WecPushLevel( p->vCubes );
vCube = Vec_WecEntry( p->vCubes, Vec_WecSize(p->vCubes) - 2 );
Vec_IntPush( vCube2, iVarNew );
Fx_ManDivAddLits( vCube, vCube2, vDiv );
Level = 2 + Abc_MaxInt( Fx_ManComputeLevelCube(p, vCube), Fx_ManComputeLevelCube(p, vCube2) );
}
assert( Vec_IntSize(p->vLevels) == iVarNew );
Vec_IntPush( p->vLevels, Level );
// do not add new cubes to the matrix
p->nLits += Vec_IntSize( vDiv );
// create new literals
vLitP = Vec_WecPushLevel( p->vLits );
vLitN = Vec_WecPushLevel( p->vLits );
vLitP = Vec_WecEntry( p->vLits, Vec_WecSize(p->vLits) - 2 );
// create updated single-cube divisor cubes
Fx_ManForEachCubeVec( p->vCubesS, p->vCubes, vCube, i )
{
RetValue = Vec_IntRemove1( vCube, Abc_LitNot(Lit0) );
RetValue += Vec_IntRemove1( vCube, Abc_LitNot(Lit1) );
assert( RetValue == 2 );
Vec_IntPush( vCube, Abc_Var2Lit(iVarNew, 0) );
Vec_IntPush( vLitP, Vec_WecLevelId(p->vCubes, vCube) );
p->nLits--;
}
// create updated double-cube divisor cube pairs
k = 0;
p->nCompls = 0;
assert( Vec_IntSize(p->vCubesD) % 2 == 0 );
assert( Vec_IntSize(p->vCubesD) == 2 * Vec_IntSize(p->vCompls) );
for ( i = 0; i < Vec_IntSize(p->vCubesD); i += 2 )
{
int fCompl = Vec_IntEntry(p->vCompls, i/2);
p->nCompls += fCompl;
vCube = Vec_WecEntry( p->vCubes, Vec_IntEntry(p->vCubesD, i) );
vCube2 = Vec_WecEntry( p->vCubes, Vec_IntEntry(p->vCubesD, i+1) );
RetValue = Fx_ManDivRemoveLits( vCube, vDiv, fCompl ); // cube 2*i
RetValue += Fx_ManDivRemoveLits( vCube2, vDiv, fCompl ); // cube 2*i+1
assert( RetValue == Vec_IntSize(vDiv) );
if ( Vec_IntSize(vDiv) == 2 || fCompl )
{
Vec_IntPush( vCube, Abc_Var2Lit(iVarNew, 1) );
Vec_IntPush( vLitN, Vec_WecLevelId(p->vCubes, vCube) );
}
else
{
Vec_IntPush( vCube, Abc_Var2Lit(iVarNew, 0) );
Vec_IntPush( vLitP, Vec_WecLevelId(p->vCubes, vCube) );
}
p->nLits -= Vec_IntSize(vDiv) + Vec_IntSize(vCube2) - 2;
// remove second cube
Vec_IntWriteEntry( p->vCubesD, k++, Vec_WecLevelId(p->vCubes, vCube) );
Vec_IntClear( vCube2 );
}
assert( k == Vec_IntSize(p->vCubesD) / 2 );
Vec_IntShrink( p->vCubesD, k );
Vec_IntSort( p->vCubesD, 0 );
// add cost of single-cube divisors
Fx_ManForEachCubeVec( p->vCubesS, p->vCubes, vCube, i )
Fx_ManCubeSingleCubeDivisors( p, vCube, 0, 1 ); // add - update
Fx_ManForEachCubeVec( p->vCubesD, p->vCubes, vCube, i )
Fx_ManCubeSingleCubeDivisors( p, vCube, 0, 1 ); // add - update
// mark the cubes to be removed
Vec_WecMarkLevels( p->vCubes, p->vCubesS );
Vec_WecMarkLevels( p->vCubes, p->vCubesD );
// add cost of double-cube divisors
Fx_ManForEachCubeVec( p->vCubesS, p->vCubes, vCube, i )
Fx_ManCubeDoubleCubeDivisors( p, Fx_ManGetFirstVarCube(p, vCube), vCube, 0, 1 ); // add - update
Fx_ManForEachCubeVec( p->vCubesD, p->vCubes, vCube, i )
Fx_ManCubeDoubleCubeDivisors( p, Fx_ManGetFirstVarCube(p, vCube), vCube, 0, 1 ); // add - update
// unmark the cubes to be removed
Vec_WecUnmarkLevels( p->vCubes, p->vCubesS );
Vec_WecUnmarkLevels( p->vCubes, p->vCubesD );
// add cost of the new divisor
if ( Vec_IntSize(vDiv) > 2 )
{
vCube = Vec_WecEntry( p->vCubes, Vec_WecSize(p->vCubes) - 2 );
vCube2 = Vec_WecEntry( p->vCubes, Vec_WecSize(p->vCubes) - 1 );
Fx_ManCubeSingleCubeDivisors( p, vCube, 0, 1 ); // add - update
Fx_ManCubeSingleCubeDivisors( p, vCube2, 0, 1 ); // add - update
Vec_IntForEachEntryStart( vCube, Lit0, i, 1 )
Vec_WecPush( p->vLits, Lit0, Vec_WecLevelId(p->vCubes, vCube) );
Vec_IntForEachEntryStart( vCube2, Lit0, i, 1 )
Vec_WecPush( p->vLits, Lit0, Vec_WecLevelId(p->vCubes, vCube2) );
}
// remove these cubes from the lit array of the divisor
Vec_IntForEachEntry( vDiv, Lit0, i )
{
Vec_IntTwoRemove( Vec_WecEntry(p->vLits, Abc_Lit2Var(Lit0)), p->vCubesD );
if ( p->nCompls && i > 1 ) // the last two lits are possibly complemented
Vec_IntTwoRemove( Vec_WecEntry(p->vLits, Abc_LitNot(Abc_Lit2Var(Lit0))), p->vCubesD );
}
// check predicted improvement: (new SOP lits == old SOP lits - divisor weight)
assert( p->nLits == nLitsNew );
}
/**Function*************************************************************
Synopsis [Implements the traditional fast_extract algorithm.]
Description [J. Rajski and J. Vasudevamurthi, "The testability-
preserving concurrent decomposition and factorization of Boolean
expressions", IEEE TCAD, Vol. 11, No. 6, June 1992, pp. 778-793.]
SideEffects []
SeeAlso []
***********************************************************************/
int Fx_FastExtract( Vec_Wec_t * vCubes, int ObjIdMax, int nNewNodesMax, int LitCountMax, int fVerbose, int fVeryVerbose )
{
int fVeryVeryVerbose = 0;
int i, iDiv;
Fx_Man_t * p;
abctime clk = Abc_Clock();
// initialize the data-structure
p = Fx_ManStart( vCubes );
p->LitCountMax = LitCountMax;
Fx_ManCreateLiterals( p, ObjIdMax );
Fx_ManComputeLevel( p );
Fx_ManCreateDivisors( p );
if ( fVeryVerbose )
Fx_PrintMatrix( p );
if ( fVerbose )
Fx_PrintStats( p, Abc_Clock() - clk );
// perform extraction
p->timeStart = Abc_Clock();
for ( i = 0; i < nNewNodesMax && Vec_QueTopPriority(p->vPrio) > 0.0; i++ )
{
iDiv = Vec_QuePop(p->vPrio);
if ( fVeryVerbose )
Fx_PrintDiv( p, iDiv );
Fx_ManUpdate( p, iDiv );
if ( fVeryVeryVerbose )
Fx_PrintMatrix( p );
}
if ( fVerbose )
Fx_PrintStats( p, Abc_Clock() - clk );
Fx_ManStop( p );
// return the result
Vec_WecRemoveEmpty( vCubes );
return 1;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END