/**CFile****************************************************************
FileName [acecXor.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [CEC for arithmetic circuits.]
Synopsis [Detection of XOR trees.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: acecXor.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "acecInt.h"
#include "misc/vec/vecWec.h"
#include "misc/extra/extra.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Acec_CheckXors( Gia_Man_t * p, Vec_Int_t * vXors )
{
Gia_Obj_t * pFan0, * pFan1;
Vec_Int_t * vCount2 = Vec_IntAlloc( Gia_ManObjNum(p) );
int i, Entry, Count = 0;
for ( i = 0; 4*i < Vec_IntSize(vXors); i++ )
if ( Vec_IntEntry(vXors, 4*i+3) == 0 )
Vec_IntAddToEntry( vCount2, Vec_IntEntry(vXors, 4*i), 1 );
Vec_IntForEachEntry( vCount2, Entry, i )
if ( Entry > 1 )
printf( "*** Obj %d has %d two-input XOR cuts.\n", i, Entry ), Count++;
else if ( Entry == 1 && Gia_ObjRecognizeExor(Gia_ManObj(p, i), &pFan0, &pFan1) )
printf( "*** Obj %d cannot be recognized as XOR.\n", i );
if ( Count == 0 )
printf( "*** There no multiple two-input XOR cuts.\n" );
Vec_IntFree( vCount2 );
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Vec_Int_t * Acec_OrderTreeRoots( Gia_Man_t * p, Vec_Int_t * vAdds, Vec_Int_t * vXorRoots, Vec_Int_t * vRanks )
{
Vec_Int_t * vOrder = Vec_IntAlloc( Vec_IntSize(vXorRoots) );
Vec_Int_t * vMove = Vec_IntStartFull( Vec_IntSize(vXorRoots) );
int i, k, Entry, This;
// iterate through adders and for each try mark the next one
for ( i = 0; 6*i < Vec_IntSize(vAdds); i++ )
{
int Node = Vec_IntEntry(vAdds, 6*i+4);
if ( Vec_IntEntry(vRanks, Node) == -1 )
continue;
for ( k = 0; k < 3; k++ )
{
int Fanin = Vec_IntEntry(vAdds, 6*i+k);
if ( Vec_IntEntry(vRanks, Fanin) == -1 )
continue;
//printf( "%4d: %2d -> %2d\n", Node, Vec_IntEntry(vRanks, Node), Vec_IntEntry(vRanks, Fanin) );
Vec_IntWriteEntry( vMove, Vec_IntEntry(vRanks, Node), Vec_IntEntry(vRanks, Fanin) );
}
}
//Vec_IntPrint( vMove );
// find reodering
Vec_IntForEachEntry( vMove, Entry, i )
if ( Entry == -1 && Vec_IntFind(vMove, i) >= 0 )
break;
assert( i < Vec_IntSize(vMove) );
while ( 1 )
{
Vec_IntPush( vOrder, Vec_IntEntry(vXorRoots, i) );
Entry = i;
Vec_IntForEachEntry( vMove, This, i )
if ( This == Entry )
break;
if ( i == Vec_IntSize(vMove) )
break;
}
Vec_IntFree( vMove );
//Vec_IntPrint( vOrder );
return vOrder;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
// marks XOR outputs
Vec_Bit_t * Acec_MapXorOuts( Gia_Man_t * p, Vec_Int_t * vXors )
{
Vec_Bit_t * vMap = Vec_BitStart( Gia_ManObjNum(p) ); int i;
for ( i = 0; 4*i < Vec_IntSize(vXors); i++ )
Vec_BitWriteEntry( vMap, Vec_IntEntry(vXors, 4*i), 1 );
return vMap;
}
// marks XOR outputs participating in trees
Vec_Bit_t * Acec_MapXorOuts2( Gia_Man_t * p, Vec_Int_t * vXors, Vec_Int_t * vRanks )
{
Vec_Bit_t * vMap = Vec_BitStart( Gia_ManObjNum(p) ); int i;
for ( i = 0; 4*i < Vec_IntSize(vXors); i++ )
if ( Vec_IntEntry(vRanks, Vec_IntEntry(vXors, 4*i)) != -1 )
Vec_BitWriteEntry( vMap, Vec_IntEntry(vXors, 4*i), 1 );
return vMap;
}
// marks MAJ outputs
Vec_Bit_t * Acec_MapMajOuts( Gia_Man_t * p, Vec_Int_t * vAdds )
{
Vec_Bit_t * vMap = Vec_BitStart( Gia_ManObjNum(p) ); int i;
for ( i = 0; 6*i < Vec_IntSize(vAdds); i++ )
Vec_BitWriteEntry( vMap, Vec_IntEntry(vAdds, 6*i+4), 1 );
return vMap;
}
// marks MAJ outputs participating in trees
Vec_Int_t * Acec_MapMajOuts2( Gia_Man_t * p, Vec_Int_t * vAdds, Vec_Int_t * vRanks )
{
Vec_Int_t * vMap = Vec_IntStartFull( Gia_ManObjNum(p) ); int i;
for ( i = 0; 6*i < Vec_IntSize(vAdds); i++ )
if ( Vec_IntEntry(vRanks, Vec_IntEntry(vAdds, 6*i+4)) != -1 )
Vec_IntWriteEntry( vMap, Vec_IntEntry(vAdds, 6*i+4), i );
return vMap;
}
// marks nodes appearing as fanins to XORs
Vec_Bit_t * Acec_MapXorIns( Gia_Man_t * p, Vec_Int_t * vXors )
{
Vec_Bit_t * vMap = Vec_BitStart( Gia_ManObjNum(p) ); int i;
for ( i = 0; 4*i < Vec_IntSize(vXors); i++ )
{
Vec_BitWriteEntry( vMap, Vec_IntEntry(vXors, 4*i+1), 1 );
Vec_BitWriteEntry( vMap, Vec_IntEntry(vXors, 4*i+2), 1 );
Vec_BitWriteEntry( vMap, Vec_IntEntry(vXors, 4*i+3), 1 );
}
return vMap;
}
// collects XOR roots (XOR nodes not appearing as fanins of other XORs)
Vec_Int_t * Acec_FindXorRoots( Gia_Man_t * p, Vec_Int_t * vXors )
{
Vec_Bit_t * vMapXorIns = Acec_MapXorIns( p, vXors );
Vec_Int_t * vXorRoots = Vec_IntAlloc( 100 ); int i;
for ( i = 0; 4*i < Vec_IntSize(vXors); i++ )
if ( !Vec_BitEntry(vMapXorIns, Vec_IntEntry(vXors, 4*i)) )
Vec_IntPushUniqueOrder( vXorRoots, Vec_IntEntry(vXors, 4*i) );
Vec_BitFree( vMapXorIns );
return vXorRoots;
}
// collects XOR trees belonging to each of XOR roots
Vec_Int_t * Acec_RankTrees( Gia_Man_t * p, Vec_Int_t * vXors, Vec_Int_t * vXorRoots )
{
Vec_Int_t * vDoubles = Vec_IntAlloc( 100 );
int i, k, Entry;
// map roots into their ranks
Vec_Int_t * vRanks = Vec_IntStartFull( Gia_ManObjNum(p) );
Vec_IntForEachEntry( vXorRoots, Entry, i )
Vec_IntWriteEntry( vRanks, Entry, i );
// map nodes into their ranks
for ( i = Vec_IntSize(vXors)/4 - 1; i >= 0; i-- )
{
int Root = Vec_IntEntry( vXors, 4*i );
int Rank = Vec_IntEntry( vRanks, Root );
// skip XORs that are not part of any tree
if ( Rank == -1 )
continue;
// iterate through XOR inputs
for ( k = 1; k < 4; k++ )
{
int Node = Vec_IntEntry( vXors, 4*i+k );
if ( Node == 0 ) // HA
continue;
Entry = Vec_IntEntry( vRanks, Node );
if ( Entry == Rank ) // the same tree
continue;
if ( Entry == -1 )
Vec_IntWriteEntry( vRanks, Node, Rank );
else
Vec_IntPush( vDoubles, Node );
if ( Entry != -1 && Gia_ObjIsAnd(Gia_ManObj(p, Node)))
printf( "Xor node %d belongs to Tree %d and Tree %d.\n", Node, Entry, Rank );
}
}
// remove duplicated entries
Vec_IntForEachEntry( vDoubles, Entry, i )
Vec_IntWriteEntry( vRanks, Entry, -1 );
Vec_IntFree( vDoubles );
return vRanks;
}
// collects leaves of each XOR tree
Vec_Wec_t * Acec_FindXorLeaves( Gia_Man_t * p, Vec_Int_t * vXors, Vec_Int_t * vAdds, Vec_Int_t * vXorRoots, Vec_Int_t * vRanks, Vec_Wec_t ** pvAddBoxes )
{
Vec_Bit_t * vMapXors = Acec_MapXorOuts2( p, vXors, vRanks );
Vec_Int_t * vMapMajs = Acec_MapMajOuts2( p, vAdds, vRanks );
Vec_Wec_t * vXorLeaves = Vec_WecStart( Vec_IntSize(vXorRoots) );
Vec_Wec_t * vAddBoxes = Vec_WecStart( Vec_IntSize(vXorRoots) );
int i, k;
for ( i = 0; 4*i < Vec_IntSize(vXors); i++ )
{
int Xor = Vec_IntEntry(vXors, 4*i);
int Rank = Vec_IntEntry(vRanks, Xor);
if ( Rank == -1 )
continue;
for ( k = 1; k < 4; k++ )
{
int Fanin = Vec_IntEntry(vXors, 4*i+k);
//int RankFanin = Vec_IntEntry(vRanks, Fanin);
if ( Fanin == 0 )
continue;
if ( Vec_BitEntry(vMapXors, Fanin) )
{
assert( Rank == Vec_IntEntry(vRanks, Fanin) );
continue;
}
// if ( Vec_BitEntry(vMapXors, Fanin) && Rank == RankFanin )
// continue;
if ( Vec_IntEntry(vMapMajs, Fanin) == -1 ) // no adder driving this input
Vec_WecPush( vXorLeaves, Rank, Fanin );
else if ( Vec_IntEntry(vRanks, Xor) > 0 ) // save adder box
Vec_WecPush( vAddBoxes, Rank-1, Vec_IntEntry(vMapMajs, Fanin) );
}
}
Vec_BitFree( vMapXors );
Vec_IntFree( vMapMajs );
if ( pvAddBoxes )
*pvAddBoxes = vAddBoxes;
return vXorLeaves;
}
void Acec_CheckBoothPPs( Gia_Man_t * p, Vec_Wec_t * vLitLeaves )
{
Vec_Bit_t * vMarked = Acec_MultMarkPPs( p );
Vec_Int_t * vLevel;
int i, k, iLit;
Vec_WecForEachLevel( vLitLeaves, vLevel, i )
{
int CountPI = 0, CountB = 0, CountNB = 0;
Vec_IntForEachEntry( vLevel, iLit, k )
if ( !Gia_ObjIsAnd(Gia_ManObj(p, Abc_Lit2Var(iLit))) )
CountPI++;
else if ( Vec_BitEntry( vMarked, Abc_Lit2Var(iLit) ) )
CountB++;
else
CountNB++;
printf( "Rank %2d : Lits = %5d PI = %d Booth = %5d Non-Booth = %5d\n", i, Vec_IntSize(vLevel), CountPI, CountB, CountNB );
}
Vec_BitFree( vMarked );
}
Acec_Box_t * Acec_FindBox( Gia_Man_t * p, Vec_Int_t * vAdds, Vec_Wec_t * vAddBoxes, Vec_Wec_t * vXorLeaves, Vec_Int_t * vXorRoots )
{
extern Vec_Int_t * Acec_TreeCarryMap( Gia_Man_t * p, Vec_Int_t * vAdds, Vec_Wec_t * vBoxes );
extern void Acec_TreePhases_rec( Gia_Man_t * p, Vec_Int_t * vAdds, Vec_Int_t * vMap, int Node, int fPhase, Vec_Bit_t * vVisit );
extern void Acec_TreeVerifyPhases( Gia_Man_t * p, Vec_Int_t * vAdds, Vec_Wec_t * vBoxes );
extern void Acec_TreeVerifyPhases2( Gia_Man_t * p, Vec_Int_t * vAdds, Vec_Wec_t * vBoxes );
int MaxRank = Vec_WecSize( vAddBoxes );
Vec_Bit_t * vVisit = Vec_BitStart( Vec_IntSize(vAdds)/6 );
Vec_Bit_t * vIsLeaf = Vec_BitStart( Gia_ManObjNum(p) );
Vec_Bit_t * vIsRoot = Vec_BitStart( Gia_ManObjNum(p) );
Vec_Int_t * vLevel, * vLevel2, * vMap;
int i, j, k, Box, Node;
Acec_Box_t * pBox = ABC_CALLOC( Acec_Box_t, 1 );
pBox->pGia = p;
pBox->vAdds = vAddBoxes; // Vec_WecDup( vAddBoxes );
pBox->vLeafLits = Vec_WecStart( MaxRank + 0 );
pBox->vRootLits = Vec_WecStart( MaxRank + 0 );
assert( Vec_WecSize(vAddBoxes) == Vec_WecSize(vXorLeaves) );
assert( Vec_WecSize(vAddBoxes) == Vec_IntSize(vXorRoots) );
// collect boxes; mark inputs/outputs
Vec_WecForEachLevel( pBox->vAdds, vLevel, i )
Vec_IntForEachEntry( vLevel, Box, k )
{
Vec_BitWriteEntry( vIsLeaf, Vec_IntEntry(vAdds, 6*Box+0), 1 );
Vec_BitWriteEntry( vIsLeaf, Vec_IntEntry(vAdds, 6*Box+1), 1 );
Vec_BitWriteEntry( vIsLeaf, Vec_IntEntry(vAdds, 6*Box+2), 1 );
Vec_BitWriteEntry( vIsRoot, Vec_IntEntry(vAdds, 6*Box+3), 1 );
Vec_BitWriteEntry( vIsRoot, Vec_IntEntry(vAdds, 6*Box+4), 1 );
}
// sort each level
Vec_WecForEachLevel( pBox->vAdds, vLevel, i )
Vec_IntSort( vLevel, 0 );
// set phases starting from roots
vMap = Acec_TreeCarryMap( p, vAdds, pBox->vAdds );
Vec_WecForEachLevelReverse( pBox->vAdds, vLevel, i )
Vec_IntForEachEntry( vLevel, Box, k )
if ( !Vec_BitEntry( vIsLeaf, Vec_IntEntry(vAdds, 6*Box+4) ) )
{
//printf( "Pushing phase of output %d of box %d\n", Vec_IntEntry(vAdds, 6*Box+4), Box );
Acec_TreePhases_rec( p, vAdds, vMap, Vec_IntEntry(vAdds, 6*Box+4), Vec_IntEntry(vAdds, 6*Box+2) != 0, vVisit );
}
Acec_TreeVerifyPhases( p, vAdds, pBox->vAdds );
Acec_TreeVerifyPhases2( p, vAdds, pBox->vAdds );
Vec_BitFree( vVisit );
Vec_IntFree( vMap );
// collect inputs/outputs
Vec_BitWriteEntry( vIsRoot, 0, 1 );
Vec_WecForEachLevel( pBox->vAdds, vLevel, i )
Vec_IntForEachEntry( vLevel, Box, j )
{
for ( k = 0; k < 3; k++ )
if ( !Vec_BitEntry( vIsRoot, Vec_IntEntry(vAdds, 6*Box+k) ) )
Vec_WecPush( pBox->vLeafLits, i, Abc_Var2Lit(Vec_IntEntry(vAdds, 6*Box+k), Acec_SignBit2(vAdds, Box, k)) );
for ( k = 3; k < 5; k++ )
if ( !Vec_BitEntry( vIsLeaf, Vec_IntEntry(vAdds, 6*Box+k) ) )
Vec_WecPush( pBox->vRootLits, k == 4 ? i + 1 : i, Abc_Var2Lit(Vec_IntEntry(vAdds, 6*Box+k), Acec_SignBit2(vAdds, Box, k)) );
if ( Vec_IntEntry(vAdds, 6*Box+2) == 0 && Acec_SignBit2(vAdds, Box, 2) )
Vec_WecPush( pBox->vLeafLits, i, 1 );
}
Vec_BitFree( vIsLeaf );
Vec_BitFree( vIsRoot );
// collect last bit
vLevel = Vec_WecEntry( pBox->vLeafLits, Vec_WecSize(pBox->vLeafLits)-1 );
vLevel2 = Vec_WecEntry( vXorLeaves, Vec_WecSize(vXorLeaves)-1 );
if ( Vec_IntSize(vLevel) == 0 && Vec_IntSize(vLevel2) > 0 )
{
Vec_IntForEachEntry( vLevel2, Node, k )
Vec_IntPush( vLevel, Abc_Var2Lit(Node, 0) );
}
vLevel = Vec_WecEntry( pBox->vRootLits, Vec_WecSize(pBox->vRootLits)-1 );
Vec_IntFill( vLevel, 1, Abc_Var2Lit(Vec_IntEntryLast(vXorRoots), 0) );
// sort each level
Vec_WecForEachLevel( pBox->vLeafLits, vLevel, i )
Vec_IntSort( vLevel, 0 );
Vec_WecForEachLevel( pBox->vRootLits, vLevel, i )
Vec_IntSort( vLevel, 1 );
//Acec_CheckBoothPPs( p, pBox->vLeafLits );
return pBox;
}
Acec_Box_t * Acec_ProduceBox( Gia_Man_t * p, int fVerbose )
{
extern void Acec_TreeVerifyConnections( Gia_Man_t * p, Vec_Int_t * vAdds, Vec_Wec_t * vBoxes );
abctime clk = Abc_Clock();
Acec_Box_t * pBox = NULL;
Vec_Int_t * vXors, * vAdds = Ree_ManComputeCuts( p, &vXors, 0 );
Vec_Int_t * vTemp, * vXorRoots = Acec_FindXorRoots( p, vXors );
Vec_Int_t * vRanks = Acec_RankTrees( p, vXors, vXorRoots );
Vec_Wec_t * vXorLeaves, * vAddBoxes = NULL;
Gia_ManLevelNum(p);
//Acec_CheckXors( p, vXors );
//Ree_ManPrintAdders( vAdds, 1 );
if ( fVerbose )
printf( "Detected %d full-adders and %d half-adders. Found %d XOR-cuts. ", Ree_ManCountFadds(vAdds), Vec_IntSize(vAdds)/6-Ree_ManCountFadds(vAdds), Vec_IntSize(vXors)/4 );
if ( fVerbose )
Abc_PrintTime( 1, "Time", Abc_Clock() - clk );
vXorRoots = Acec_OrderTreeRoots( p, vAdds, vTemp = vXorRoots, vRanks );
Vec_IntFree( vTemp );
Vec_IntFree( vRanks );
vRanks = Acec_RankTrees( p, vXors, vXorRoots );
vXorLeaves = Acec_FindXorLeaves( p, vXors, vAdds, vXorRoots, vRanks, &vAddBoxes );
Vec_IntFree( vRanks );
//printf( "XOR roots after reordering: \n" );
//Vec_IntPrint( vXorRoots );
//printf( "XOR leaves: \n" );
//Vec_WecPrint( vXorLeaves, 0 );
//printf( "Adder boxes: \n" );
//Vec_WecPrint( vAddBoxes, 0 );
Acec_TreeVerifyConnections( p, vAdds, vAddBoxes );
pBox = Acec_FindBox( p, vAdds, vAddBoxes, vXorLeaves, vXorRoots );
//Vec_WecFree( vAddBoxes );
if ( fVerbose )
Acec_TreePrintBox( pBox, vAdds );
Vec_IntFree( vXorRoots );
Vec_WecFree( vXorLeaves );
Vec_IntFree( vXors );
Vec_IntFree( vAdds );
return pBox;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END