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/**CFile****************************************************************
FileName [retCore.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Retiming package.]
Synopsis [The core retiming procedures.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - Oct 31, 2006.]
Revision [$Id: retCore.c,v 1.00 2006/10/31 00:00:00 alanmi Exp $]
***********************************************************************/
#include "retInt.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
clock_t timeRetime = 0;
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Implementation of retiming.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_NtkRetime( Abc_Ntk_t * pNtk, int Mode, int nDelayLim, int fForwardOnly, int fBackwardOnly, int fOneStep, int fVerbose )
{
int nLatches = Abc_NtkLatchNum(pNtk);
int nLevels = Abc_NtkLevel(pNtk);
int RetValue = 0;
clock_t clkTotal = clock();
int nNodesOld, nLatchesOld;
assert( Mode > 0 && Mode < 7 );
assert( !fForwardOnly || !fBackwardOnly );
// cleanup the network
nNodesOld = Abc_NtkNodeNum(pNtk);
nLatchesOld = Abc_NtkLatchNum(pNtk);
Abc_NtkCleanupSeq(pNtk, 0, 0, 0);
if ( nNodesOld > Abc_NtkNodeNum(pNtk) || nLatchesOld > Abc_NtkLatchNum(pNtk) )
printf( "Cleanup before retiming removed %d dangling nodes and %d dangling latches.\n",
nNodesOld - Abc_NtkNodeNum(pNtk), nLatchesOld - Abc_NtkLatchNum(pNtk) );
// perform retiming
switch ( Mode )
{
case 1: // forward
RetValue = Abc_NtkRetimeIncremental( pNtk, nDelayLim, 1, 0, 0, fVerbose );
break;
case 2: // backward
RetValue = Abc_NtkRetimeIncremental( pNtk, nDelayLim, 0, 0, 0, fVerbose );
break;
case 3: // min-area
RetValue = Abc_NtkRetimeMinArea( pNtk, fForwardOnly, fBackwardOnly, fVerbose );
break;
case 4: // min-delay
if ( !fBackwardOnly )
RetValue += Abc_NtkRetimeIncremental( pNtk, nDelayLim, 1, 1, fOneStep, fVerbose );
if ( !fForwardOnly )
RetValue += Abc_NtkRetimeIncremental( pNtk, nDelayLim, 0, 1, fOneStep, fVerbose );
break;
case 5: // min-area + min-delay
RetValue = Abc_NtkRetimeMinArea( pNtk, fForwardOnly, fBackwardOnly, fVerbose );
if ( !fBackwardOnly )
RetValue += Abc_NtkRetimeIncremental( pNtk, nDelayLim, 1, 1, 0, fVerbose );
if ( !fForwardOnly )
RetValue += Abc_NtkRetimeIncremental( pNtk, nDelayLim, 0, 1, 0, fVerbose );
break;
case 6: // Pan's algorithm
RetValue = Abc_NtkRetimeLValue( pNtk, 500, fVerbose );
break;
default:
printf( "Unknown retiming option.\n" );
break;
}
if ( fVerbose )
{
printf( "Reduction in area = %3d. Reduction in delay = %3d. ",
nLatches - Abc_NtkLatchNum(pNtk), nLevels - Abc_NtkLevel(pNtk) );
ABC_PRT( "Total runtime", clock() - clkTotal );
}
timeRetime = clock() - clkTotal;
return RetValue;
}
/**Function*************************************************************
Synopsis [Used for automated debugging.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_NtkRetimeDebug( Abc_Ntk_t * pNtk )
{
extern int Abc_NtkSecFraig( Abc_Ntk_t * pNtk1, Abc_Ntk_t * pNtk2, int nSeconds, int nFrames, int fVerbose );
Abc_Ntk_t * pNtkRet;
assert( Abc_NtkIsLogic(pNtk) );
Abc_NtkToSop( pNtk, 0 );
// if ( !Abc_NtkCheck( pNtk ) )
// fprintf( stdout, "Abc_NtkRetimeDebug(): Network check has failed.\n" );
// Io_WriteBlifLogic( pNtk, "debug_temp.blif", 1 );
pNtkRet = Abc_NtkDup( pNtk );
Abc_NtkRetime( pNtkRet, 3, 0, 0, 1, 0, 0 ); // debugging backward flow
return !Abc_NtkSecFraig( pNtk, pNtkRet, 10000, 3, 0 );
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END
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