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|
/**CFile****************************************************************
FileName [abcSop.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Network and node package.]
Synopsis [Implementation of a simple SOP representation of nodes.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: abcSop.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "abc.h"
/*
The SOPs in this package are represented using char * strings.
For example, the SOP of the node:
.names c d0 d1 MUX
01- 1
1-1 1
is the string: "01- 1/n1-1 1/n" where '/n' is a single char.
*/
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Registers the cube string with the network.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopRegister( Extra_MmFlex_t * pMan, char * pName )
{
char * pRegName;
if ( pName == NULL ) return NULL;
pRegName = Extra_MmFlexEntryFetch( pMan, strlen(pName) + 1 );
strcpy( pRegName, pName );
return pRegName;
}
/**Function*************************************************************
Synopsis [Creates the constant 1 cover with the given number of variables and cubes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopStart( Extra_MmFlex_t * pMan, int nCubes, int nVars )
{
char * pSopCover, * pCube;
int i, Length;
Length = nCubes * (nVars + 3);
pSopCover = Extra_MmFlexEntryFetch( pMan, Length + 1 );
memset( pSopCover, '-', Length );
pSopCover[Length] = 0;
for ( i = 0; i < nCubes; i++ )
{
pCube = pSopCover + i * (nVars + 3);
pCube[nVars + 0] = ' ';
pCube[nVars + 1] = '1';
pCube[nVars + 2] = '\n';
}
return pSopCover;
}
/**Function*************************************************************
Synopsis [Creates the constant 1 cover with 0 variables.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateConst1( Extra_MmFlex_t * pMan )
{
return Abc_SopRegister( pMan, " 1\n" );
}
/**Function*************************************************************
Synopsis [Creates the constant 1 cover with 0 variables.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateConst0( Extra_MmFlex_t * pMan )
{
return Abc_SopRegister( pMan, " 0\n" );
}
/**Function*************************************************************
Synopsis [Creates the AND2 cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateAnd2( Extra_MmFlex_t * pMan, int fCompl0, int fCompl1 )
{
char Buffer[6];
Buffer[0] = '1' - fCompl0;
Buffer[1] = '1' - fCompl1;
Buffer[2] = ' ';
Buffer[3] = '1';
Buffer[4] = '\n';
Buffer[5] = 0;
return Abc_SopRegister( pMan, Buffer );
}
/**Function*************************************************************
Synopsis [Creates the multi-input AND cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateAnd( Extra_MmFlex_t * pMan, int nVars, int * pfCompl )
{
char * pSop;
int i;
pSop = Abc_SopStart( pMan, 1, nVars );
for ( i = 0; i < nVars; i++ )
pSop[i] = '1' - (pfCompl? pfCompl[i] : 0);
pSop[nVars + 1] = '1';
return pSop;
}
/**Function*************************************************************
Synopsis [Creates the multi-input NAND cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateNand( Extra_MmFlex_t * pMan, int nVars )
{
char * pSop;
int i;
pSop = Abc_SopStart( pMan, 1, nVars );
for ( i = 0; i < nVars; i++ )
pSop[i] = '1';
pSop[nVars + 1] = '0';
return pSop;
}
/**Function*************************************************************
Synopsis [Creates the multi-input OR cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateOr( Extra_MmFlex_t * pMan, int nVars, int * pfCompl )
{
char * pSop;
int i;
pSop = Abc_SopStart( pMan, 1, nVars );
for ( i = 0; i < nVars; i++ )
pSop[i] = '0' + (pfCompl? pfCompl[i] : 0);
pSop[nVars + 1] = '0';
return pSop;
}
/**Function*************************************************************
Synopsis [Creates the multi-input OR cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateOrMultiCube( Extra_MmFlex_t * pMan, int nVars, int * pfCompl )
{
char * pSop, * pCube;
int i;
pSop = Abc_SopStart( pMan, nVars, nVars );
i = 0;
Abc_SopForEachCube( pSop, nVars, pCube )
{
pCube[i] = '1' - (pfCompl? pfCompl[i] : 0);
i++;
}
return pSop;
}
/**Function*************************************************************
Synopsis [Creates the multi-input NOR cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateNor( Extra_MmFlex_t * pMan, int nVars )
{
char * pSop;
int i;
pSop = Abc_SopStart( pMan, 1, nVars );
for ( i = 0; i < nVars; i++ )
pSop[i] = '0';
return pSop;
}
/**Function*************************************************************
Synopsis [Creates the multi-input XOR cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateXor( Extra_MmFlex_t * pMan, int nVars )
{
assert( nVars == 2 );
return Abc_SopRegister(pMan, "01 1\n10 1\n");
}
/**Function*************************************************************
Synopsis [Creates the multi-input XOR cover (special case).]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateXorSpecial( Extra_MmFlex_t * pMan, int nVars )
{
char * pSop;
pSop = Abc_SopCreateAnd( pMan, nVars, NULL );
pSop[nVars+1] = 'x';
assert( pSop[nVars+2] == '\n' );
return pSop;
}
/**Function*************************************************************
Synopsis [Creates the multi-input XNOR cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateNxor( Extra_MmFlex_t * pMan, int nVars )
{
assert( nVars == 2 );
return Abc_SopRegister(pMan, "11 1\n00 1\n");
}
/**Function*************************************************************
Synopsis [Creates the MUX cover.]
Description [The first input of MUX is the control. The second input
is DATA1. The third input is DATA0.]
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateMux( Extra_MmFlex_t * pMan )
{
return Abc_SopRegister(pMan, "11- 1\n0-1 1\n");
}
/**Function*************************************************************
Synopsis [Creates the inv cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateInv( Extra_MmFlex_t * pMan )
{
return Abc_SopRegister(pMan, "0 1\n");
}
/**Function*************************************************************
Synopsis [Creates the buf cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateBuf( Extra_MmFlex_t * pMan )
{
return Abc_SopRegister(pMan, "1 1\n");
}
/**Function*************************************************************
Synopsis [Creates the arbitrary cover from the truth table.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopCreateFromTruth( Extra_MmFlex_t * pMan, int nVars, unsigned * pTruth )
{
char * pSop, * pCube;
int nMints, Counter, i, k;
// count the number of true minterms
Counter = 0;
nMints = (1 << nVars);
for ( i = 0; i < nMints; i++ )
Counter += ((pTruth[i>>5] & (1 << (i&31))) > 0);
// SOP is not well-defined if the truth table is constant 0
assert( Counter > 0 );
if ( Counter == 0 )
return NULL;
// start the cover
pSop = Abc_SopStart( pMan, Counter, nVars );
// create true minterms
Counter = 0;
for ( i = 0; i < nMints; i++ )
if ( (pTruth[i>>5] & (1 << (i&31))) > 0 )
{
pCube = pSop + Counter * (nVars + 3);
for ( k = 0; k < nVars; k++ )
pCube[k] = '0' + ((i & (1 << k)) > 0);
Counter++;
}
return pSop;
}
/**Function*************************************************************
Synopsis [Reads the number of cubes in the cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_SopGetCubeNum( char * pSop )
{
char * pCur;
int nCubes = 0;
if ( pSop == NULL )
return 0;
for ( pCur = pSop; *pCur; pCur++ )
nCubes += (*pCur == '\n');
return nCubes;
}
/**Function*************************************************************
Synopsis [Reads the number of SOP literals in the cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_SopGetLitNum( char * pSop )
{
char * pCur;
int nLits = 0;
if ( pSop == NULL )
return 0;
for ( pCur = pSop; *pCur; pCur++ )
{
nLits -= (*pCur == '\n');
nLits += (*pCur == '0' || *pCur == '1');
}
return nLits;
}
/**Function*************************************************************
Synopsis [Reads the number of variables in the cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_SopGetVarNum( char * pSop )
{
char * pCur;
for ( pCur = pSop; *pCur != '\n'; pCur++ );
return pCur - pSop - 2;
}
/**Function*************************************************************
Synopsis [Reads the phase of the cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_SopGetPhase( char * pSop )
{
int nVars = Abc_SopGetVarNum( pSop );
if ( pSop[nVars+1] == '0' || pSop[nVars+1] == 'n' )
return 0;
if ( pSop[nVars+1] == '1' || pSop[nVars+1] == 'x' )
return 1;
assert( 0 );
return -1;
}
/**Function*************************************************************
Synopsis [Returns the i-th literal of the cover.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_SopGetIthCareLit( char * pSop, int i )
{
char * pCube;
int nVars;
nVars = Abc_SopGetVarNum( pSop );
Abc_SopForEachCube( pSop, nVars, pCube )
if ( pCube[i] != '-' )
return pCube[i] - '0';
return -1;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Abc_SopComplement( char * pSop )
{
char * pCur;
for ( pCur = pSop; *pCur; pCur++ )
if ( *pCur == '\n' )
{
if ( *(pCur - 1) == '0' )
*(pCur - 1) = '1';
else if ( *(pCur - 1) == '1' )
*(pCur - 1) = '0';
else if ( *(pCur - 1) == 'x' )
*(pCur - 1) = 'n';
else if ( *(pCur - 1) == 'n' )
*(pCur - 1) = 'x';
else
assert( 0 );
}
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
bool Abc_SopIsComplement( char * pSop )
{
char * pCur;
for ( pCur = pSop; *pCur; pCur++ )
if ( *pCur == '\n' )
return (int)(*(pCur - 1) == '0' || *(pCur - 1) == 'n');
assert( 0 );
return 0;
}
/**Function*************************************************************
Synopsis [Checks if the cover is constant 0.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
bool Abc_SopIsConst0( char * pSop )
{
return pSop[0] == ' ' && pSop[1] == '0';
}
/**Function*************************************************************
Synopsis [Checks if the cover is constant 1.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
bool Abc_SopIsConst1( char * pSop )
{
return pSop[0] == ' ' && pSop[1] == '1';
}
/**Function*************************************************************
Synopsis [Checks if the cover is constant 1.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
bool Abc_SopIsBuf( char * pSop )
{
if ( pSop[4] != 0 )
return 0;
if ( (pSop[0] == '1' && pSop[2] == '1') || (pSop[0] == '0' && pSop[2] == '0') )
return 1;
return 0;
}
/**Function*************************************************************
Synopsis [Checks if the cover is constant 1.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
bool Abc_SopIsInv( char * pSop )
{
if ( pSop[4] != 0 )
return 0;
if ( (pSop[0] == '0' && pSop[2] == '1') || (pSop[0] == '1' && pSop[2] == '0') )
return 1;
return 0;
}
/**Function*************************************************************
Synopsis [Checks if the cover is AND with possibly complemented inputs.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
bool Abc_SopIsAndType( char * pSop )
{
char * pCur;
if ( Abc_SopGetCubeNum(pSop) != 1 )
return 0;
for ( pCur = pSop; *pCur != ' '; pCur++ )
if ( *pCur == '-' )
return 0;
if ( pCur[1] != '1' )
return 0;
return 1;
}
/**Function*************************************************************
Synopsis [Checks if the cover is OR with possibly complemented inputs.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
bool Abc_SopIsOrType( char * pSop )
{
char * pCube, * pCur;
int nVars, nLits;
nVars = Abc_SopGetVarNum( pSop );
if ( nVars != Abc_SopGetCubeNum(pSop) )
return 0;
Abc_SopForEachCube( pSop, nVars, pCube )
{
// count the number of literals in the cube
nLits = 0;
for ( pCur = pCube; *pCur != ' '; pCur++ )
nLits += ( *pCur != '-' );
if ( nLits != 1 )
return 0;
}
return 1;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_SopIsExorType( char * pSop )
{
char * pCur;
for ( pCur = pSop; *pCur; pCur++ )
if ( *pCur == '\n' )
return (int)(*(pCur - 1) == 'x' || *(pCur - 1) == 'n');
assert( 0 );
return 0;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
bool Abc_SopCheck( char * pSop, int nFanins )
{
char * pCubes, * pCubesOld;
int fFound0 = 0, fFound1 = 0;
// check the logic function of the node
for ( pCubes = pSop; *pCubes; pCubes++ )
{
// get the end of the next cube
for ( pCubesOld = pCubes; *pCubes != ' '; pCubes++ );
// compare the distance
if ( pCubes - pCubesOld != nFanins )
{
fprintf( stdout, "Abc_SopCheck: SOP has a mismatch between its cover and its fanins.\n" );
return 0;
}
// check the output values for this cube
pCubes++;
if ( *pCubes == '0' )
fFound0 = 1;
else if ( *pCubes == '1' )
fFound1 = 1;
else if ( *pCubes != 'x' && *pCubes != 'n' )
{
fprintf( stdout, "Abc_SopCheck: SOP has a strange character in the output part of its cube.\n" );
return 0;
}
// check the last symbol (new line)
pCubes++;
if ( *pCubes != '\n' )
{
fprintf( stdout, "Abc_SopCheck: SOP has a cube without new line in the end.\n" );
return 0;
}
}
if ( fFound0 && fFound1 )
{
fprintf( stdout, "Abc_SopCheck: SOP has cubes in both phases.\n" );
return 0;
}
return 1;
}
/**Function*************************************************************
Synopsis [Writes the CNF of the SOP into file.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Abc_SopWriteCnf( FILE * pFile, char * pClauses, Vec_Int_t * vVars )
{
char * pChar;
int i;
// check the logic function of the node
for ( pChar = pClauses; *pChar; pChar++ )
{
// write the clause
for ( i = 0; i < vVars->nSize; i++, pChar++ )
if ( *pChar == '0' )
fprintf( pFile, "%d ", vVars->pArray[i] );
else if ( *pChar == '1' )
fprintf( pFile, "%d ", -vVars->pArray[i] );
fprintf( pFile, "0\n" );
// check that the remainig part is fine
assert( *pChar == ' ' );
pChar++;
assert( *pChar == '1' );
pChar++;
assert( *pChar == '\n' );
}
}
/**Function*************************************************************
Synopsis [Adds the clauses of for the CNF to the solver.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Abc_SopAddCnfToSolver( solver * pSat, char * pClauses, Vec_Int_t * vVars, Vec_Int_t * vTemp )
{
char * pChar;
int i, RetValue;
// check the logic function of the node
for ( pChar = pClauses; *pChar; pChar++ )
{
// add the clause
vTemp->nSize = 0;
for ( i = 0; i < vVars->nSize; i++, pChar++ )
if ( *pChar == '0' )
Vec_IntPush( vTemp, toLit(vVars->pArray[i]) );
else if ( *pChar == '1' )
Vec_IntPush( vTemp, neg(toLit(vVars->pArray[i])) );
// add the clause to the solver
RetValue = solver_addclause( pSat, vTemp->pArray, vTemp->pArray + vTemp->nSize );
assert( RetValue != 1 );
// check that the remainig part is fine
assert( *pChar == ' ' );
pChar++;
assert( *pChar == '1' );
pChar++;
assert( *pChar == '\n' );
}
}
/**Function*************************************************************
Synopsis [Derives SOP from the truth table representation.]
Description [Truth table is expected to be in the hexadecimal notation.]
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopFromTruthBin( char * pTruth )
{
char * pSopCover, * pCube;
int nTruthSize, nVars, Digit, Length, Mint, i, b;
Vec_Int_t * vMints;
// get the number of variables
nTruthSize = strlen(pTruth);
nVars = Extra_Base2Log( nTruthSize );
if ( nTruthSize != (1 << (nVars)) )
{
printf( "String %s does not look like a truth table of a %d-variable function.\n", pTruth, nVars );
return NULL;
}
// collect the on-set minterms
vMints = Vec_IntAlloc( 100 );
for ( i = 0; i < nTruthSize; i++ )
{
if ( pTruth[i] >= '0' && pTruth[i] <= '1' )
Digit = pTruth[i] - '0';
else
{
printf( "String %s does not look like a binary representation of the truth table.\n", pTruth );
return NULL;
}
if ( Digit == 1 )
Vec_IntPush( vMints, nTruthSize - 1 - i );
}
// create the SOP representation of the minterms
Length = Vec_IntSize(vMints) * (nVars + 3);
pSopCover = ALLOC( char, Length + 1 );
pSopCover[Length] = 0;
Vec_IntForEachEntry( vMints, Mint, i )
{
pCube = pSopCover + i * (nVars + 3);
for ( b = 0; b < nVars; b++ )
if ( Mint & (1 << b) )
pCube[b] = '1';
else
pCube[b] = '0';
pCube[nVars + 0] = ' ';
pCube[nVars + 1] = '1';
pCube[nVars + 2] = '\n';
}
Vec_IntFree( vMints );
return pSopCover;
}
/**Function*************************************************************
Synopsis [Derives SOP from the truth table representation.]
Description [Truth table is expected to be in the hexadecimal notation.]
SideEffects []
SeeAlso []
***********************************************************************/
char * Abc_SopFromTruthHex( char * pTruth )
{
char * pSopCover, * pCube;
int nTruthSize, nVars, Digit, Length, Mint, i, b;
Vec_Int_t * vMints;
// get the number of variables
nTruthSize = strlen(pTruth);
nVars = Extra_Base2Log( nTruthSize ) + 2;
if ( nTruthSize != (1 << (nVars-2)) )
{
printf( "String %s does not look like a truth table of a %d-variable function.\n", pTruth, nVars );
return NULL;
}
// collect the on-set minterms
vMints = Vec_IntAlloc( 100 );
for ( i = 0; i < nTruthSize; i++ )
{
if ( pTruth[i] >= '0' && pTruth[i] <= '9' )
Digit = pTruth[i] - '0';
else if ( pTruth[i] >= 'a' && pTruth[i] <= 'f' )
Digit = 10 + pTruth[i] - 'a';
else if ( pTruth[i] >= 'A' && pTruth[i] <= 'F' )
Digit = 10 + pTruth[i] - 'A';
else
{
printf( "String %s does not look like a hexadecimal representation of the truth table.\n", pTruth );
return NULL;
}
for ( b = 0; b < 4; b++ )
if ( Digit & (1 << b) )
Vec_IntPush( vMints, 4*(nTruthSize-1-i)+b );
}
// create the SOP representation of the minterms
Length = Vec_IntSize(vMints) * (nVars + 3);
pSopCover = ALLOC( char, Length + 1 );
pSopCover[Length] = 0;
Vec_IntForEachEntry( vMints, Mint, i )
{
pCube = pSopCover + i * (nVars + 3);
for ( b = 0; b < nVars; b++ )
if ( Mint & (1 << b) )
pCube[b] = '1';
else
pCube[b] = '0';
pCube[nVars + 0] = ' ';
pCube[nVars + 1] = '1';
pCube[nVars + 2] = '\n';
}
Vec_IntFree( vMints );
return pSopCover;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
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