/**CFile****************************************************************
FileName [dauDsd2.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [DAG-aware unmapping.]
Synopsis [Disjoint-support decomposition.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: dauDsd2.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "dauInt.h"
#include "misc/util/utilTruth.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
#include DSD_MAX_VAR 12
#include DSD_MAX_WRD ((DSD_MAX_VAR > 6) ? (1 << (DSD_MAX_VAR-6)) : 1)
typedef struct Dua_Obj_t_ Dua_Obj_t;
struct Dua_Obj_t_
{
int Type; // dec type (1=var; 2=and; 3=xor; 4=mux; 5=prime)
int nFans; // fanin count
char pFans[DSD_MAX_VAR]; // fanins
};
typedef struct Dua_Dsd_t_ Dua_Dsd_t;
struct Dua_Dsd_t_
{
int nSupp; // original variables
int nVars; // remaining variables
int nWords; // largest non-dec prime
int nObjs; // object count
int iRoot; // the root of the tree
Dua_Obj_t pObjs[DSD_MAX_VAR]; // objects
word pTruth[DSD_MAX_WRD]; // original/current truth table
};
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Makes the fCof1-th cofactor of iVar the 0-th cofactor.]
Description [Variable iVar becomes last varaible; others shift back.
Only the 0-th cofactor is computed.]
SideEffects []
SeeAlso []
***********************************************************************/
static inline word Abc_Tt6HalfUnShuffleVars( word t, int iVar, int fCof1 )
{
static word Masks[6] = {
ABC_CONST(0x5555555555555555),
ABC_CONST(0x3333333333333333),
ABC_CONST(0x0F0F0F0F0F0F0F0F),
ABC_CONST(0x00FF00FF00FF00FF),
ABC_CONST(0x0000FFFF0000FFFF),
ABC_CONST(0x00000000FFFFFFFF)
};
int v, s = (1 << iVar);
t = (t >> (fCof1 ? 0 : s)) & Masks[iVar];
for ( v = iVar, s = (1 << v); v < 5; v++, s <<= 1 )
t = ((t >> s) | t) & Masks[v+1];
return t;
}
static inline void Abc_TtHalfUnShuffleVars( word * pTruth, int nVars, int iVar, int jVar, int fCof1 )
{
int w, nWords = Abc_TtWordNum( nVars );
if ( iVar == jVar )
return;
assert( iVar < jVar );
if ( iVar < 5 )
{
for ( w = 0; w < nWords; w++ )
pTruth[w] = Abc_Tt6HalfUnShuffleVars( pTruth[w], iVar, fCof1 );
iVar = 5;
}
if ( jVar < 6 )
{
for ( w = 0; w < nWords; w++ )
pTruth[w] = (pTruth[w] << 32) | pTruth[w];
return;
}
if ( iVar == 5 )
{
unsigned * pTruthU = (unsigned *)pTruth;
for ( w = 0; w < nWords; w += 2 )
pTruthU[w] = pTruthU[w+1];
iVar = 6;
}
{
word * pLimit = pTruth + nWords;
int i, iStep = Abc_TtWordNum(iVar);
int j, jStep = Abc_TtWordNum(jVar);
for ( ; pTruth < pLimit; pTruth += jStep )
for ( i = 0; i < jStep; i += iStep )
for ( j = 0; j < iStep; j++ )
pTruth[w++] = pTruth[iStep + i + j];
assert( w == (nWords >> 1) );
return;
}
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Dua_DsdInit( Dua_Dsd_t * pRes, word * pTruth, int nVars )
{
int i;
pRes->nSupp = nVars;
pRes->nVars = nVars;
pRes->nWords = Abc_TtWordNum( nVars );
pRes->nObjs = 1;
pRes->iRoot = Abc_Var2Lit( 0, 0 );
pRes->pObjs[0].Type = 5;
pRes->pObjs[0].nFans = nVars;
for ( i = 0; i < nVars; i++ )
pRes->pObjs[0].pFans[i] = (char)Abc_Var2Lit( i, 0 );
memcpy( pRes->pTruth, pTruth, sizeof(word) * pRes->nWords );
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
// returns 1 if the truth table was complemented
int Dua_DsdTryConst( word * pTruth, int nVars )
{
if ( !(pTruth[0] & 1) )
return 0;
Abc_TtNot( pTruth, Abc_TtWordNum(nVars) );
return 1;
}
int Dua_DsdTryVar( word * pTruth, int nWords, int iVar )
{
int nWordsI = Abc_TtWordNum(iVar);
word c0 = (iVar < 6) ? Abc_Tt6Cofactor0( pTruth[0], iVar ) : pTruth[0];
word c1 = (iVar < 6) ? Abc_Tt6Cofactor1( pTruth[0], iVar ) : pTruth[nWords];
if ( c0 != c1 )
{
if ( c1 < c0 && c1 < ~c1 ) // flip
{
Abc_TtFlip( pTruth, nWords, iVar );
return 0;
}
if ( ~c1 < c0 && ~c1 < c1 ) // flip and compl
{
Abc_TtFlipNot( pTruth, nWords, iVar );
return 1;
}
}
if ( iVar < 6 )
{
word * pLimit = pTruth + nWords;
for ( pTruth++; pTruth < pLimit; pTruth++ )
{
c0 = Abc_Tt6Cofactor0( pTruth[0], iVar );
c1 = Abc_Tt6Cofactor1( pTruth[0], iVar );
if ( c0 == c1 )
continue;
if ( c0 < c1 )
return 0;
for ( ; pTruth < pLimit; pTruth++ )
pTruth[0] = Abc_Tt6Flip( pTruth[0], iVar );
return 0;
}
}
else
{
for ( ; pTruth < pLimit; pTruth += (nWordsI << 1) )
for ( w = 0; w < nWordsI; w++ )
{
c0 = pTruth[0];
c1 = pTruth[nWordsI];
if ( c0 == c1 )
continue;
if ( c0 < c1 )
return 0;
for ( ; pTruth < pLimit; pTruth += (nWordsI << 1) )
for ( ; w < nWordsI; w++ )
ABC_SWAP( word, pTruth[0], pTruth[nWordsI] );
return 0;
}
}
assert( 0 );
return -1;
}
int Dua_DsdCheckCof0Const0( word * pTruth, int nWords, int iVar )
{
if ( nWords == 1 )
return (pTruth[0] & s_Truths6Neg[iVar]) == 0;
if ( iVar <= 5 )
{
int w;
for ( w = 0; w < nWords; w++ )
if ( (pTruth[w] & s_Truths6Neg[iVar]) )
return 0;
return 1;
}
else // if ( iVar > 5 )
{
word * pLimit = pTruth + nWords;
int i, iStep = Abc_TtWordNum(iVar);
for ( ; pTruth < pLimit; pTruth += (iStep << 1) )
for ( i = 0; i < iStep; i++ )
if ( pTruth[i] )
return 0;
return 1;
}
}
int Dua_DsdCheckCofsEqualNot( word * pTruth, int nWords, int iVar )
{
if ( nWords == 1 )
return (pTruth[0] & s_Truths6Neg[iVar]) == ((~pTruth[0] & s_Truths6[iVar]) >> (1 << iVar));
if ( iVar <= 5 )
{
int w, shift = (1 << iVar);
for ( w = 0; w < nWords; w++ )
if ( (pTruth[w] & s_Truths6Neg[iVar]) != ((~pTruth[w] & s_Truths6[iVar]) >> shift) )
return 0;
return 1;
}
else // if ( iVar > 5 )
{
word * pLimit = pTruth + nWords;
int i, iStep = Abc_TtWordNum(iVar);
for ( ; pTruth < pLimit; pTruth += (iStep << 1) )
for ( i = 0; i < iStep; i++ )
if ( pTruth[i] != ~pTruth[i + iStep] )
return 0;
return 1;
}
}
int Dua_DsdOneVar( Dua_Dsd_t * pRes )
{
int v, fCompl, fChange = 1;
fCompl = Dua_DsdTryConst( pRes->pTruth, pRes->nWords );
while ( fChange && pRes->nVars > 2 )
{
fChange = 0;
for ( v = 0; v < pRes->nVars; v++ )
{
fCompl ^= Dua_DsdTryVar( pRes->pTruth, pRes->nWords, v );
if ( Dua_DsdCheckCof0Const0( pRes->pTruth, pRes->nWords, v ) )
{
fChange = 1;
// record AND(v, F)
}
else if ( Dua_DsdCheckCofsEqualNot( pRes->pTruth, pRes->nWords, v ) )
{
fChange = 1;
// record XOR(v, F)
}
}
}
return fCompl;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Dua_DsdTrySwap( word * pTruth, int nWords, int iVar )
{
static word s_PMasks[5][3] = {
{ ABC_CONST(0x9999999999999999), ABC_CONST(0x2222222222222222), ABC_CONST(0x4444444444444444) },
{ ABC_CONST(0xC3C3C3C3C3C3C3C3), ABC_CONST(0x0C0C0C0C0C0C0C0C), ABC_CONST(0x3030303030303030) },
{ ABC_CONST(0xF00FF00FF00FF00F), ABC_CONST(0x00F000F000F000F0), ABC_CONST(0x0F000F000F000F00) },
{ ABC_CONST(0xFF0000FFFF0000FF), ABC_CONST(0x0000FF000000FF00), ABC_CONST(0x00FF000000FF0000) },
{ ABC_CONST(0xFFFF00000000FFFF), ABC_CONST(0x00000000FFFF0000), ABC_CONST(0x0000FFFF00000000) }
};
if ( iVar < 5 )
{
int Shift = (1 << iVar);
word c01, c10, * pLimit = pTruth + nWords;
for ( ; pTruth < pLimit; pTruth++ )
{
c01 = (pTruth[0] & s_PMasks[iVar][1]);
c10 = (pTruth[0] & s_PMasks[iVar][2]) >> Shift;
if ( c01 == c10 )
continue;
if ( c01 < c10 )
return 0;
pTruth[0] = (pTruth[0] & s_PMasks[iVar][0]) | ((pTruth[0] & s_PMasks[iVar][1]) << Shift) | ((pTruth[0] & s_PMasks[iVar][2]) >> Shift);
return 1;
}
}
else if ( iVar == 5 )
{
unsigned * pTruthU = (unsigned *)pTruth;
unsigned * pLimitU = (unsigned *)(pTruth + nWords);
for ( ; pTruthU < pLimitU; pTruthU += 4 )
{
c01 = pTruthU[1];
c10 = pTruthU[2];
if ( c01 == c10 )
continue;
if ( c01 < c10 )
return 0;
for ( ; pTruthU < pLimitU; pTruthU += 4 )
ABC_SWAP( unsigned, pTruthU[1], pTruthU[2] );
return 1;
}
}
else // if ( iVar > 5 )
{
word * pLimit = pTruth + nWords;
int i, iStep = Abc_TtWordNum(iVar);
for ( ; pTruth < pLimit; pTruth += 4*iStep )
for ( i = 0; i < iStep; i++ )
{
c01 = pTruth[i + iStep];
c10 = pTruth[i + 2*iStep];
if ( c01 == c10 )
continue;
if ( c01 < c10 )
return 0;
for ( ; pTruth < pLimit; pTruth += 4*iStep )
for ( ; i < iStep; i++ )
ABC_SWAP( word, pTruth[1], pTruth[2] );
return 1;
}
}
return 2;
}
int Dua_DsdCheckDecomp( word * pTruth, int nWords, int iVar )
{
static word s_PMasks[5][4] = {
{ ABC_CONST(0x1111111111111111), ABC_CONST(0x2222222222222222), ABC_CONST(0x4444444444444444), ABC_CONST(0x8888888888888888) },
{ ABC_CONST(0x0303030303030303), ABC_CONST(0x0C0C0C0C0C0C0C0C), ABC_CONST(0x3030303030303030), ABC_CONST(0xC0C0C0C0C0C0C0C0) },
{ ABC_CONST(0x000F000F000F000F), ABC_CONST(0x00F000F000F000F0), ABC_CONST(0x0F000F000F000F00), ABC_CONST(0xF000F000F000F000) },
{ ABC_CONST(0x000000FF000000FF), ABC_CONST(0x0000FF000000FF00), ABC_CONST(0x00FF000000FF0000), ABC_CONST(0xFF000000FF000000) },
{ ABC_CONST(0x000000000000FFFF), ABC_CONST(0x00000000FFFF0000), ABC_CONST(0x0000FFFF00000000), ABC_CONST(0xFFFF000000000000) }
};
int fC0eC1 = 1, fC0eC3 = 1;
if ( iVar < 5 )
{
int Shift = (1 << iVar);
word c01, c10, * pLimit = pTruth + nWords;
for ( ; pTruth < pLimit; pTruth++ )
{
if ( fC0eC1 && (pTruth[0] & s_PMasks[iVar][0]) != ((pTruth[0] & s_PMasks[iVar][1]) >> Shift) )
fC0eC1 = 0;
if ( fC0eC3 && (pTruth[0] & s_PMasks[iVar][0]) != ((pTruth[0] & s_PMasks[iVar][3]) >> (3*Shift)) )
fC0eC3 = 0;
if ( !fC0eC1 && !fC0eC3 )
return 0;
}
}
if ( iVar == 5 )
{
unsigned * pTruthU = (unsigned *)pTruth;
unsigned * pLimitU = (unsigned *)(pTruth + nWords);
for ( ; pTruthU < pLimitU; pTruthU += 4 )
{
if ( fC0eC1 && pTruthU[0] != pTruthU[1] )
fC0eC1 = 0;
if ( fC0eC3 && pTruthU[0] != pTruthU[3] )
fC0eC3 = 0;
if ( !fC0eC1 && !fC0eC3 )
return 0;
}
}
else // if ( iVar > 5 )
{
word * pLimit = pTruth + nWords;
int i, iStep = Abc_TtWordNum(iVar);
for ( ; pTruth < pLimit; pTruth += 4*iStep )
for ( i = 0; i < iStep; i++ )
{
if ( fC0eC1 && pTruth[0] != pTruth[1] )
fC0eC1 = 0;
if ( fC0eC3 && pTruth[0] != pTruth[3] )
fC0eC3 = 0;
if ( !fC0eC1 && !fC0eC3 )
return 0;
}
}
assert( fC0eC1 != fC0eC3 );
return fC0eC1 ? 1 : 2;
}
// returns 1 if decomposition detected
int Dua_DsdTwoVars( Dua_Dsd_t * pRes )
{
int v, RetValue, fChange = 1;
while ( fChange && pRes->nVars > 2 )
{
fChange = 0;
for ( v = 0; v < pRes->nVars - 1; v++ )
{
RetValue = Dua_DsdTrySwap( pRes->pTruth, pRes->nWords, v );
if ( RetValue == 1 )
fChange = 1;
if ( RetValue != 2 )
continue;
// vars are symmetric, check decomp
RetValue = Dua_DsdCheckDecomp( pRes->pTruth, pRes->nWords, v );
if ( RetValue == 0 )
continue;
if ( RetValue == 1 )
{
fChange = 1;
// record AND(a, b)
}
else
{
fChange = 1;
// record XOR(a, b)
}
}
}
}
/**Function*************************************************************
Synopsis [Check DSD for bound-set [iVar; jVar).]
Description [Return D-func if decomposable.]
SideEffects []
SeeAlso []
***********************************************************************/
word Dua_DsdRangeVars( word * pTruth, int nVars, int iVar, int jVar, int fPerform )
{
int Part, nParts = 1 << (nVars - jVar);
int Mint, nMints = 1 << (jVar - iVar);
word MaskOne, MaskAll = 0;
assert( jVar - iVar > 2 );
assert( jVar - iVar < 7 );
if ( iVar < 6 )
{
int Shift = 6 - iVar, MaskF = (1 << Shift) - 1, iMint = 0;
word MaskFF = (((word)1) << (1 << iVar)) - 1;
word Cof0, Cof1, Value;
for ( Part = 0; Part < nParts; Part++ )
{
MaskOne = 0;
Cof0 = Cof1 = ~(word)0;
for ( Mint = 0; Mint < nMints; Mint++, iMint++ )
{
Value = (pTruth[iMint>>Shift] >> ((iMint & MaskF)<<iVar)) & MaskFF;
if ( !~Cof0 || Cof0 == Value )
Cof0 = Value;
else if ( !~Cof1 || Cof1 == Value )
{
Cof1 = Value;
MaskOne |= ((word)1) << Mint;
}
else
return 0;
}
if ( Part == 0 )
MaskAll = MaskOne;
else if ( MaskAll != MaskOne )
return 0;
if ( fPerform )
{
assert( ~Cof0 && ~Cof1 );
Mint = 2 * Part;
Value = (pTruth[Mint>>Shift] >> ((Mint & MaskF)<<nVarsF)) & MaskFF;
pTruth[Mint>>Shift] ^= (Value ^ Cof0) << ((Mint & MaskF)<<nVarsF)
Mint = 2 * Part + 1;
Value = (pTruth[Mint>>Shift] >> ((Mint & MaskF)<<nVarsF)) & MaskFF;
pTruth[Mint>>Shift] ^= (Value ^ Cof1) << ((Mint & MaskF)<<nVarsF)
}
}
// stretch
if ( nVars - (jVar - iVar) + 1 < 6 )
pTruth[0] = Abc_Tt6Stretch( pTruth[0], nVars - (jVar - iVar) + 1 );
}
else
{
int nWordsF = Abc_TtWordNum(iVar);
int iWord = 0, nBytes = sizeof(word) * nWordsF;
word * pCof0, * pCof1;
for ( Part = 0; Part < nParts; Part++ )
{
MaskOne = 0;
pCof0 = pCof1 = NULL;
for ( Mint = 0; Mint < nMints; Mint++, iWord += nWordsF )
{
if ( !pCof0 || !memcmp(pCof0, pTruth + iWord, nBytes) )
pCof0 = pTruth + iWord;
else if ( !pCof1 || !memcmp(pCof1, pTruth + iWord, nBytes) )
{
pCof1 = pTruth + iWord;
MaskOne |= ((word)1) << Mint;
}
else
return 0;
}
if ( Part == 0 )
MaskAll = MaskOne;
else if ( MaskAll != MaskOne )
return 0;
if ( fPerform )
{
assert( pCof0 && pCof1 );
memcpy( pTruth + (2 * Part + 0) * nWordsF, pCof0, nBytes );
memcpy( pTruth + (2 * Part + 1) * nWordsF, pCof1, nBytes );
}
}
}
return MaskAll;
}
/**Function*************************************************************
Synopsis [Check DSD for bound-set [0; iVar).]
Description [Return D-func if decomposable.]
SideEffects []
SeeAlso []
***********************************************************************/
int Dua_DsdRangeVars0( word * pTruth, int nVars, int iVar, int fPerform )
{
int i, nParts = 1 << (nVars - iVar);
assert( iVar > 2 && iVar < nVars );
if ( iVar == 3 )
{
unsigned char * pTruthP = (unsigned char *)pTruth, Dfunc = pTruthP[0];
for ( i = 1; i < nParts; i++ )
if ( pTruthP[i] != Dfunc && pTruthP[i] != ~Dfunc )
return 0;
}
else if ( iVar == 4 )
{
unsigned short * pTruthP = (unsigned short *)pTruth, Dfunc = pTruthP[0];
for ( i = 1; i < nParts; i++ )
if ( pTruthP[i] != Dfunc && pTruthP[i] != ~Dfunc )
return 0;
}
else if ( iVar == 5 )
{
unsigned int * pTruthP = (unsigned int *)pTruth, Dfunc = pTruthP[0];
for ( i = 1; i < nParts; i++ )
if ( pTruthP[i] != Dfunc && pTruthP[i] != ~Dfunc )
return 0;
}
else
{
int nStep = 1 << (6 - iVar);
assert( iVar >= 6 );
for ( i = 1; i < nParts; i++ )
if ( !Abc_TtEqual(pTruth, pTruth + i * nStep, nStep) && !Abc_TtEqualNot(pTruth, pTruth + i * nStep, nStep) )
return 0;
}
return 1;
}
void Dua_DsdRangeVars0Derive( word * pTruth, int nVars, int iVar )
{
int i, nParts = 1 << (nVars - iVar);
assert( iVar > 2 && iVar < nVars );
if ( iVar == 3 )
{
unsigned char * pTruthP = (unsigned char *)pTruth, Dfunc = pTruthP[0];
for ( i = 0; i < nParts; i++ )
if ( Abc_TtGetBit(pTruth, i) ^ (pTruthP[i] != Dfunc) )
Abc_TtXorBit(pTruth, i);
}
else if ( iVar == 4 )
{
unsigned short * pTruthP = (unsigned short *)pTruth, Dfunc = pTruthP[0];
for ( i = 0; i < nParts; i++ )
if ( Abc_TtGetBit(pTruth, i) ^ (pTruthP[i] != Dfunc) )
Abc_TtXorBit(pTruth, i);
}
else if ( iVar == 5 )
{
unsigned int * pTruthP = (unsigned int *)pTruth, Dfunc = pTruthP[0];
for ( i = 0; i < nParts; i++ )
if ( Abc_TtGetBit(pTruth, i) ^ (pTruthP[i] != Dfunc) )
Abc_TtXorBit(pTruth, i);
}
else
{
word Dfunc = pTruth[0];
assert( iVar == 6 );
for ( i = 0; i < nParts; i++ )
if ( Abc_TtGetBit(pTruth, i) ^ (pTruth[i] != Dfunc) )
Abc_TtXorBit(pTruth, i);
}
// stretch
if ( nVars - iVar + 1 < 6 )
pTruth[0] = Abc_Tt6Stretch( pTruth[0], nVars - iVar + 1 < 6 );
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Dua_DsdTest( word * pTruth, int nVar )
{
Dua_Dsd_t Res, * pRes = &Res;
Dua_DsdInit( pRes, pTruth, nVars );
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END