summaryrefslogtreecommitdiffstats
path: root/src/base/seq/seqAigIter.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/base/seq/seqAigIter.c')
-rw-r--r--src/base/seq/seqAigIter.c273
1 files changed, 0 insertions, 273 deletions
diff --git a/src/base/seq/seqAigIter.c b/src/base/seq/seqAigIter.c
deleted file mode 100644
index b71312f7..00000000
--- a/src/base/seq/seqAigIter.c
+++ /dev/null
@@ -1,273 +0,0 @@
-/**CFile****************************************************************
-
- FileName [seqRetIter.c]
-
- SystemName [ABC: Logic synthesis and verification system.]
-
- PackageName [Construction and manipulation of sequential AIGs.]
-
- Synopsis [The iterative L-Value computation for retiming procedures.]
-
- Author [Alan Mishchenko]
-
- Affiliation [UC Berkeley]
-
- Date [Ver. 1.0. Started - June 20, 2005.]
-
- Revision [$Id: seqRetIter.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
-
-***********************************************************************/
-
-#include "seqInt.h"
-
-ABC_NAMESPACE_IMPL_START
-
-
-////////////////////////////////////////////////////////////////////////
-/// DECLARATIONS ///
-////////////////////////////////////////////////////////////////////////
-
-// the internal procedures
-static int Seq_RetimeSearch_rec( Abc_Ntk_t * pNtk, int FiMin, int FiMax, int fVerbose );
-static int Seq_RetimeForPeriod( Abc_Ntk_t * pNtk, int Fi, int fVerbose );
-static int Seq_RetimeNodeUpdateLValue( Abc_Obj_t * pObj, int Fi );
-
-////////////////////////////////////////////////////////////////////////
-/// FUNCTION DEFINITIONS ///
-////////////////////////////////////////////////////////////////////////
-
-/**Function*************************************************************
-
- Synopsis [Retimes AIG for optimal delay using Pan's algorithm.]
-
- Description []
-
- SideEffects []
-
- SeeAlso []
-
-***********************************************************************/
-int Seq_AigRetimeDelayLags( Abc_Ntk_t * pNtk, int fVerbose )
-{
- Abc_Seq_t * p = pNtk->pManFunc;
- Abc_Obj_t * pNode;
- int i, FiMax, RetValue, clk, clkIter;
- char NodeLag;
-
- assert( Abc_NtkIsSeq( pNtk ) );
-
- // get the upper bound on the clock period
- FiMax = 2 + Seq_NtkLevelMax(pNtk);
-
- // make sure this clock period is feasible
- if ( !Seq_RetimeForPeriod( pNtk, FiMax, fVerbose ) )
- {
- Vec_StrFill( p->vLags, p->nSize, 0 );
- printf( "Error: The upper bound on the clock period cannot be computed.\n" );
- printf( "The reason for this error may be the presence in the circuit of logic\n" );
- printf( "that is not reachable from the PIs. Mapping/retiming is not performed.\n" );
- return 0;
- }
-
- // search for the optimal clock period between 0 and nLevelMax
-clk = clock();
- p->FiBestInt = Seq_RetimeSearch_rec( pNtk, 0, FiMax, fVerbose );
-clkIter = clock() - clk;
-
- // recompute the best l-values
- RetValue = Seq_RetimeForPeriod( pNtk, p->FiBestInt, fVerbose );
- assert( RetValue );
-
- // fix the problem with non-converged delays
- Abc_AigForEachAnd( pNtk, pNode, i )
- if ( Seq_NodeGetLValue(pNode) < -ABC_INFINITY/2 )
- Seq_NodeSetLValue( pNode, 0 );
-
- // write the retiming lags
- Vec_StrFill( p->vLags, p->nSize, 0 );
- Abc_AigForEachAnd( pNtk, pNode, i )
- {
- NodeLag = Seq_NodeComputeLag( Seq_NodeGetLValue(pNode), p->FiBestInt );
- Seq_NodeSetLag( pNode, NodeLag );
- }
-
- // print the result
- if ( fVerbose )
- printf( "The best clock period is %3d.\n", p->FiBestInt );
-
-/*
- printf( "lvalues and lags : " );
- Abc_AigForEachAnd( pNtk, pNode, i )
- printf( "%d=%d(%d) ", pNode->Id, Seq_NodeGetLValue(pNode), Seq_NodeGetLag(pNode) );
- printf( "\n" );
-*/
-/*
- {
- FILE * pTable;
- pTable = fopen( "stats.txt", "a+" );
- fprintf( pTable, "%s ", pNtk->pName );
- fprintf( pTable, "%d ", FiBest );
- fprintf( pTable, "\n" );
- fclose( pTable );
- }
-*/
-/*
- {
- FILE * pTable;
- pTable = fopen( "stats.txt", "a+" );
- fprintf( pTable, "%s ", pNtk->pName );
- fprintf( pTable, "%.2f ", (float)(p->timeCuts)/(float)(CLOCKS_PER_SEC) );
- fprintf( pTable, "%.2f ", (float)(clkIter)/(float)(CLOCKS_PER_SEC) );
- fprintf( pTable, "\n" );
- fclose( pTable );
- }
-*/
- return 1;
-
-}
-
-/**Function*************************************************************
-
- Synopsis [Performs binary search for the optimal clock period.]
-
- Description [Assumes that FiMin is infeasible while FiMax is feasible.]
-
- SideEffects []
-
- SeeAlso []
-
-***********************************************************************/
-int Seq_RetimeSearch_rec( Abc_Ntk_t * pNtk, int FiMin, int FiMax, int fVerbose )
-{
- int Median;
- assert( FiMin < FiMax );
- if ( FiMin + 1 == FiMax )
- return FiMax;
- Median = FiMin + (FiMax - FiMin)/2;
- if ( Seq_RetimeForPeriod( pNtk, Median, fVerbose ) )
- return Seq_RetimeSearch_rec( pNtk, FiMin, Median, fVerbose ); // Median is feasible
- else
- return Seq_RetimeSearch_rec( pNtk, Median, FiMax, fVerbose ); // Median is infeasible
-}
-
-/**Function*************************************************************
-
- Synopsis [Returns 1 if retiming with this clock period is feasible.]
-
- Description []
-
- SideEffects []
-
- SeeAlso []
-
-***********************************************************************/
-int Seq_RetimeForPeriod( Abc_Ntk_t * pNtk, int Fi, int fVerbose )
-{
- Abc_Seq_t * p = pNtk->pManFunc;
- Abc_Obj_t * pObj;
- int i, c, RetValue, fChange, Counter;
- char * pReason = "";
-
- // set l-values of all nodes to be minus infinity
- Vec_IntFill( p->vLValues, p->nSize, -ABC_INFINITY );
-
- // set l-values of constants and PIs
- pObj = Abc_NtkObj( pNtk, 0 );
- Seq_NodeSetLValue( pObj, 0 );
- Abc_NtkForEachPi( pNtk, pObj, i )
- Seq_NodeSetLValue( pObj, 0 );
-
- // update all values iteratively
- Counter = 0;
- for ( c = 0; c < p->nMaxIters; c++ )
- {
- fChange = 0;
- Abc_AigForEachAnd( pNtk, pObj, i )
- {
- Counter++;
- if ( Seq_NodeCutMan(pObj) )
- RetValue = Seq_FpgaNodeUpdateLValue( pObj, Fi );
- else
- RetValue = Seq_RetimeNodeUpdateLValue( pObj, Fi );
- if ( RetValue == SEQ_UPDATE_YES )
- fChange = 1;
- }
- Abc_NtkForEachPo( pNtk, pObj, i )
- {
- if ( Seq_NodeCutMan(pObj) )
- RetValue = Seq_FpgaNodeUpdateLValue( pObj, Fi );
- else
- RetValue = Seq_RetimeNodeUpdateLValue( pObj, Fi );
- if ( RetValue == SEQ_UPDATE_FAIL )
- break;
- }
- if ( RetValue == SEQ_UPDATE_FAIL )
- break;
- if ( fChange == 0 )
- break;
- }
- if ( c == p->nMaxIters )
- {
- RetValue = SEQ_UPDATE_FAIL;
- pReason = "(timeout)";
- }
- else
- c++;
- // report the results
- if ( fVerbose )
- {
- if ( RetValue == SEQ_UPDATE_FAIL )
- printf( "Period = %3d. Iterations = %3d. Updates = %10d. Infeasible %s\n", Fi, c, Counter, pReason );
- else
- printf( "Period = %3d. Iterations = %3d. Updates = %10d. Feasible\n", Fi, c, Counter );
- }
-/*
- // check if any AND gates have infinite delay
- Counter = 0;
- Abc_AigForEachAnd( pNtk, pObj, i )
- Counter += (Seq_NodeGetLValue(pObj) < -ABC_INFINITY/2);
- if ( Counter > 0 )
- printf( "Warning: %d internal nodes have wrong l-values!\n", Counter );
-*/
- return RetValue != SEQ_UPDATE_FAIL;
-}
-
-/**Function*************************************************************
-
- Synopsis [Computes the l-value of the node.]
-
- Description [The node can be internal or a PO.]
-
- SideEffects []
-
- SeeAlso []
-
-***********************************************************************/
-int Seq_RetimeNodeUpdateLValue( Abc_Obj_t * pObj, int Fi )
-{
- int lValueNew, lValueOld, lValue0, lValue1;
- assert( !Abc_ObjIsPi(pObj) );
- assert( Abc_ObjFaninNum(pObj) > 0 );
- lValue0 = Seq_NodeGetLValue(Abc_ObjFanin0(pObj)) - Fi * Seq_ObjFaninL0(pObj);
- if ( Abc_ObjIsPo(pObj) )
- return (lValue0 > Fi)? SEQ_UPDATE_FAIL : SEQ_UPDATE_NO;
- if ( Abc_ObjFaninNum(pObj) == 2 )
- lValue1 = Seq_NodeGetLValue(Abc_ObjFanin1(pObj)) - Fi * Seq_ObjFaninL1(pObj);
- else
- lValue1 = -ABC_INFINITY;
- lValueNew = 1 + ABC_MAX( lValue0, lValue1 );
- lValueOld = Seq_NodeGetLValue(pObj);
-// if ( lValueNew == lValueOld )
- if ( lValueNew <= lValueOld )
- return SEQ_UPDATE_NO;
- Seq_NodeSetLValue( pObj, lValueNew );
- return SEQ_UPDATE_YES;
-}
-
-////////////////////////////////////////////////////////////////////////
-/// END OF FILE ///
-////////////////////////////////////////////////////////////////////////
-
-
-ABC_NAMESPACE_IMPL_END
-
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-30 18:26:54 +0000