/**CFile****************************************************************
FileName [sclTime.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [Standard-cell library representation.]
Synopsis [Static timing analysis using Liberty delay model.]
Author [Alan Mishchenko, Niklas Een]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - August 24, 2012.]
Revision [$Id: sclTime.c,v 1.0 2012/08/24 00:00:00 alanmi Exp $]
***********************************************************************/
#include "sclInt.h"
#include "sclMan.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Finding most critical nodes/fanins/path.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Abc_Obj_t * Abc_SclFindCriticalCo( SC_Man * p, int * pfRise )
{
Abc_Obj_t * pObj, * pPivot = NULL;
float fMaxArr = 0;
int i;
Abc_NtkForEachCo( p->pNtk, pObj, i )
{
SC_Pair * pArr = Abc_SclObjTime( p, pObj );
if ( fMaxArr < pArr->rise ) fMaxArr = pArr->rise, *pfRise = 1, pPivot = pObj;
if ( fMaxArr < pArr->fall ) fMaxArr = pArr->fall, *pfRise = 0, pPivot = pObj;
}
assert( pPivot != NULL );
return pPivot;
}
Abc_Obj_t * Abc_SclFindMostCriticalFanin( SC_Man * p, int * pfRise, Abc_Obj_t * pNode )
{
Abc_Obj_t * pObj, * pPivot = NULL;
float fMaxArr = 0;
int i;
Abc_ObjForEachFanin( pNode, pObj, i )
{
SC_Pair * pArr = Abc_SclObjTime( p, pObj );
if ( fMaxArr < pArr->rise ) fMaxArr = pArr->rise, *pfRise = 1, pPivot = pObj;
if ( fMaxArr < pArr->fall ) fMaxArr = pArr->fall, *pfRise = 0, pPivot = pObj;
}
return pPivot;
}
/**Function*************************************************************
Synopsis [Printing timing information for the node/network.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline void Abc_SclTimeGatePrint( SC_Man * p, Abc_Obj_t * pObj, int fRise )
{
printf( "%5d : ", Abc_ObjId(pObj) );
printf( "%-10s ", Abc_SclObjCell(p, pObj)->pName );
if ( fRise >= 0 )
printf( "(%s) ", fRise ? "rise" : "fall" );
printf( "delay = (" );
printf( "%7.1f ps ", Abc_SclObjTimePs(p, pObj, 1) );
printf( "%7.1f ps ) ", Abc_SclObjTimePs(p, pObj, 0) );
printf( "load =%6.2f ff ", Abc_SclObjLoadFf(p, pObj, fRise >= 0 ? fRise : 0 ) );
printf( "slew =%6.1f ps ", Abc_SclObjSlewPs(p, pObj, fRise >= 0 ? fRise : 0 ) );
printf( "\n" );
}
void Abc_SclTimeNtkPrint( SC_Man * p, int fShowAll )
{
int i, fRise = 0;
Abc_Obj_t * pObj = Abc_SclFindCriticalCo( p, &fRise );
printf( "WireLoad model = \"%s\". ", p->pWLoadUsed );
printf( "Total area = %10.2f. ", Abc_SclGetTotalArea( p ) );
printf( "Critical delay = %.1f ps\n", Abc_SclObjTimePs(p, pObj, fRise) );
if ( fShowAll )
{
// printf( "Timing information for all nodes: \n" );
Abc_NtkForEachNodeReverse( p->pNtk, pObj, i )
if ( Abc_ObjFaninNum(pObj) > 0 )
Abc_SclTimeGatePrint( p, pObj, -1 );
}
else
{
// printf( "Critical path: \n" );
pObj = Abc_ObjFanin0(pObj);
while ( pObj && Abc_ObjIsNode(pObj) )
{
printf( "Critical path -- " );
Abc_SclTimeGatePrint( p, pObj, fRise );
pObj = Abc_SclFindMostCriticalFanin( p, &fRise, pObj );
}
}
}
/**Function*************************************************************
Synopsis [Timing computation for pin/gate/cone/network.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline float Abc_SclLookup( SC_Surface * p, float slew, float load )
{
float * pIndex0, * pIndex1, * pDataS, * pDataS1;
float sfrac, lfrac, p0, p1;
int s, l;
// Find closest sample points in surface:
pIndex0 = Vec_FltArray(p->vIndex0);
for ( s = 1; s < Vec_FltSize(p->vIndex0)-1; s++ )
if ( pIndex0[s] > slew )
break;
s--;
pIndex1 = Vec_FltArray(p->vIndex1);
for ( l = 1; l < Vec_FltSize(p->vIndex1)-1; l++ )
if ( pIndex1[l] > load )
break;
l--;
// Interpolate (or extrapolate) function value from sample points:
sfrac = (slew - pIndex0[s]) / (pIndex0[s+1] - pIndex0[s]);
lfrac = (load - pIndex1[l]) / (pIndex1[l+1] - pIndex1[l]);
pDataS = Vec_FltArray( (Vec_Flt_t *)Vec_PtrEntry(p->vData, s) );
pDataS1 = Vec_FltArray( (Vec_Flt_t *)Vec_PtrEntry(p->vData, s+1) );
p0 = pDataS [l] + lfrac * (pDataS [l+1] - pDataS [l]);
p1 = pDataS1[l] + lfrac * (pDataS1[l+1] - pDataS1[l]);
return p0 + sfrac * (p1 - p0); // <<== multiply result with K factor here
}
void Abc_SclTimePin( SC_Man * p, SC_Timing * pTime, Abc_Obj_t * pObj, Abc_Obj_t * pFanin )
{
SC_Pair * pArrIn = Abc_SclObjTime( p, pFanin );
SC_Pair * pSlewIn = Abc_SclObjSlew( p, pFanin );
SC_Pair * pLoad = Abc_SclObjLoad( p, pObj );
SC_Pair * pArrOut = Abc_SclObjTime( p, pObj ); // modified
SC_Pair * pSlewOut = Abc_SclObjSlew( p, pObj ); // modified
if (pTime->tsense == sc_ts_Pos || pTime->tsense == sc_ts_Non)
{
pArrOut->rise = Abc_MaxFloat( pArrOut->rise, pArrIn->rise + Abc_SclLookup(pTime->pCellRise, pSlewIn->rise, pLoad->rise) );
pArrOut->fall = Abc_MaxFloat( pArrOut->fall, pArrIn->fall + Abc_SclLookup(pTime->pCellFall, pSlewIn->fall, pLoad->fall) );
pSlewOut->rise = Abc_MaxFloat( pSlewOut->rise, Abc_SclLookup(pTime->pRiseTrans, pSlewIn->rise, pLoad->rise) );
pSlewOut->fall = Abc_MaxFloat( pSlewOut->fall, Abc_SclLookup(pTime->pFallTrans, pSlewIn->fall, pLoad->fall) );
}
if (pTime->tsense == sc_ts_Neg || pTime->tsense == sc_ts_Non)
{
pArrOut->rise = Abc_MaxFloat( pArrOut->rise, pArrIn->fall + Abc_SclLookup(pTime->pCellRise, pSlewIn->fall, pLoad->rise) );
pArrOut->fall = Abc_MaxFloat( pArrOut->fall, pArrIn->rise + Abc_SclLookup(pTime->pCellFall, pSlewIn->rise, pLoad->fall) );
pSlewOut->rise = Abc_MaxFloat( pSlewOut->rise, Abc_SclLookup(pTime->pRiseTrans, pSlewIn->fall, pLoad->rise) );
pSlewOut->fall = Abc_MaxFloat( pSlewOut->fall, Abc_SclLookup(pTime->pFallTrans, pSlewIn->rise, pLoad->fall) );
}
}
void Abc_SclTimeGate( SC_Man * p, Abc_Obj_t * pObj )
{
SC_Timings * pRTime;
SC_Timing * pTime;
SC_Pin * pPin;
SC_Cell * pCell;
int k;
if ( Abc_ObjIsCo(pObj) )
{
Abc_SclObjDupFanin( p, pObj );
return;
}
assert( Abc_ObjIsNode(pObj) );
// get the library cell
pCell = Abc_SclObjCell( p, pObj );
// get the output pin
assert( pCell->n_outputs == 1 );
pPin = SC_CellPin( pCell, pCell->n_inputs );
// compute timing using each fanin
assert( Vec_PtrSize(pPin->vRTimings) == pCell->n_inputs );
Vec_PtrForEachEntry( SC_Timings *, pPin->vRTimings, pRTime, k )
{
assert( Vec_PtrSize(pRTime->vTimings) == 1 );
pTime = (SC_Timing *)Vec_PtrEntry( pRTime->vTimings, 0 );
Abc_SclTimePin( p, pTime, pObj, Abc_ObjFanin(pObj, k) );
}
}
void Abc_SclTimeCone( SC_Man * p, Vec_Int_t * vCone )
{
int fVerbose = 0;
Abc_Obj_t * pObj;
int i;
Abc_NtkForEachObjVec( vCone, p->pNtk, pObj, i )
{
if ( fVerbose && Abc_ObjIsNode(pObj) )
printf( " Updating node %d with gate %s\n", Abc_ObjId(pObj), Abc_SclObjCell(p, pObj)->pName );
if ( fVerbose && Abc_ObjIsNode(pObj) )
printf( " before (%6.1f ps %6.1f ps) ", Abc_SclObjTimePs(p, pObj, 1), Abc_SclObjTimePs(p, pObj, 0) );
Abc_SclTimeGate( p, pObj );
if ( fVerbose && Abc_ObjIsNode(pObj) )
printf( "after (%6.1f ps %6.1f ps)\n", Abc_SclObjTimePs(p, pObj, 1), Abc_SclObjTimePs(p, pObj, 0) );
}
}
void Abc_SclTimeNtk( SC_Man * p )
{
Abc_Obj_t * pObj;
int i;
Abc_NtkForEachNode1( p->pNtk, pObj, i )
Abc_SclTimeGate( p, pObj );
Abc_NtkForEachCo( p->pNtk, pObj, i )
Abc_SclObjDupFanin( p, pObj );
}
/**Function*************************************************************
Synopsis [Prepare timing manager.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
SC_Man * Abc_SclManStart( SC_Lib * pLib, Abc_Ntk_t * pNtk )
{
SC_Man * p = Abc_SclManAlloc( pLib, pNtk );
assert( p->vGates == NULL );
p->vGates = Abc_SclManFindGates( pLib, pNtk );
Abc_SclComputeLoad( p );
Abc_SclTimeNtk( p );
p->SumArea = p->SumArea0 = Abc_SclGetTotalArea( p );
p->MaxDelay0 = Abc_SclGetMaxDelay( p );
return p;
}
/**Function*************************************************************
Synopsis [Printing out timing information for the network.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Abc_SclTimePerform( SC_Lib * pLib, Abc_Ntk_t * pNtk, int fShowAll )
{
SC_Man * p;
p = Abc_SclManStart( pLib, pNtk );
Abc_SclTimeNtkPrint( p, fShowAll );
Abc_SclManFree( p );
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END