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abc
Commit 1d25ae3b by Alan Mishchenko
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Experiment with technology mapping.

parent d2cab859
Showing with 247 additions and 105 deletions
src/base/abci/abc.c
......@@ -13612,14 +13612,21 @@ usage:
***********************************************************************/
int Abc_CommandIfif( Abc_Frame_t * pAbc, int argc, char ** argv )
{
extern void Abc_NtkPerformIfif( Abc_Ntk_t * pNtk, int nDelayLut, int nDegree, int fVerbose );
extern void Abc_NtkPerformIfif( Abc_Ntk_t * pNtk, Ifif_Par_t * pPars );
Abc_Ntk_t * pNtk = Abc_FrameReadNtk(pAbc);
int c;
int nDelayLut = 5;
int nDegree = 3;
int fVerbose = 0;
Ifif_Par_t Pars, * pPars = &Pars;
int c, fError;
pPars->nLutSize = -1; // the LUT size
pPars->pLutLib = (If_Lib_t *)Abc_FrameReadLibLut(); // the LUT library
pPars->DelayWire = (float)0.5; // wire delay
pPars->nDegree = 0; // structure degree
pPars->fCascade = 0; // cascade
pPars->fVerbose = 0; // verbose
pPars->fVeryVerbose = 0; // verbose
Extra_UtilGetoptReset();
while ( ( c = Extra_UtilGetopt( argc, argv, "DNvh" ) ) != EOF )
while ( ( c = Extra_UtilGetopt( argc, argv, "DNcvwh" ) ) != EOF )
{
switch ( c )
{
......@@ -13629,9 +13636,9 @@ int Abc_CommandIfif( Abc_Frame_t * pAbc, int argc, char ** argv )
Abc_Print( -1, "Command line switch \"-D\" should be followed by a floating point number.\n" );
goto usage;
}
nDelayLut = atoi(argv[globalUtilOptind]);
pPars->DelayWire = atof(argv[globalUtilOptind]);
globalUtilOptind++;
if ( nDelayLut <= 0.0 )
if ( pPars->DelayWire < 0.0 )
goto usage;
break;
case 'N':
......@@ -13640,13 +13647,19 @@ int Abc_CommandIfif( Abc_Frame_t * pAbc, int argc, char ** argv )
Abc_Print( -1, "Command line switch \"-N\" should be followed by a floating point number.\n" );
goto usage;
}
nDegree = atoi(argv[globalUtilOptind]);
pPars->nDegree = atoi(argv[globalUtilOptind]);
globalUtilOptind++;
if ( nDegree < 0 )
if ( pPars->nDegree < 0 )
goto usage;
break;
case 'c':
pPars->fCascade ^= 1;
break;
case 'v':
fVerbose ^= 1;
pPars->fVerbose ^= 1;
break;
case 'w':
pPars->fVeryVerbose ^= 1;
break;
case 'h':
goto usage;
......@@ -13665,15 +13678,48 @@ int Abc_CommandIfif( Abc_Frame_t * pAbc, int argc, char ** argv )
Abc_Print( -1, "Need mapped network.\n" );
return 1;
}
Abc_NtkPerformIfif( pNtk, nDelayLut, nDegree, fVerbose );
if ( pPars->pLutLib == NULL )
{
Abc_Print( -1, "LUT library is not given.\n" );
return 1;
}
pPars->nLutSize = Abc_NtkGetFaninMax( pNtk );
if ( pPars->nLutSize > pPars->pLutLib->LutMax )
{
Abc_Print( -1, "The max node size (%d) exceeds the LUT size (%d).\n", pPars->nLutSize, pPars->pLutLib->LutMax );
return 1;
}
if ( pPars->nLutSize < pPars->pLutLib->LutMax )
Abc_Print( 0, "Node size (%d) is less than LUT size (%d).\n", pPars->nLutSize, pPars->pLutLib->LutMax );
// check delay information
fError = 0;
for ( c = 0; c < pPars->pLutLib->LutMax; c++ )
{
pPars->pLutDelays[c] = ( pPars->pLutLib->fVarPinDelays ? pPars->pLutLib->pLutDelays[pPars->pLutLib->LutMax][c] : pPars->pLutLib->pLutDelays[pPars->pLutLib->LutMax][0] );
if ( pPars->DelayWire >= pPars->pLutDelays[c] )
{
fError = 1;
printf(" Wire delay (%.2f) exceeds pin+wire delay (%.2f) for pin %d in the LUT library.\n", pPars->DelayWire, pPars->pLutDelays[c], c );
}
}
if ( fError )
return 1;
// call the mapper
Abc_NtkPerformIfif( pNtk, pPars );
return 0;
usage:
Abc_Print( -2, "usage: ifif [-DNvh]\n" );
Abc_Print( -2, "\t experimental technology mapper\n" );
Abc_Print( -2, "\t-D num : the ratio of LUT delay to wire delay [default = %d]\n", nDelayLut );
Abc_Print( -2, "\t-N num : degree of the combination of LUTs [default = %d]\n", nDegree );
Abc_Print( -2, "\t-v : toggles verbose output [default = %s]\n", fVerbose? "yes": "no" );
Abc_Print( -2, "usage: ifif [-DNcvwh]\n" );
Abc_Print( -2, "\t technology mapper into N-node K-LUT structures\n" );
Abc_Print( -2, "\t (takes a LUT network and maps it into a delay-optimal network\n" );
Abc_Print( -2, "\t of N-node K-LUT structures using the current LUT library)\n" );
Abc_Print( -2, "\t-D float : wire delay (should be less than the LUT delay) [default = %.2f]\n", pPars->DelayWire );
Abc_Print( -2, "\t-N num : degree of the LUT structure [default = %d]\n", pPars->nDegree );
Abc_Print( -2, "\t-c : toggles using LUT cascade vs LUT cluster [default = %s]\n", pPars->fCascade? "cascade": "cluster" );
Abc_Print( -2, "\t-v : toggles verbose output [default = %s]\n", pPars->fVerbose? "yes": "no" );
Abc_Print( -2, "\t-w : toggles very verbose output [default = %s]\n", pPars->fVeryVerbose? "yes": "no" );
Abc_Print( -2, "\t-h : print the command usage\n");
return 1;
}
......
src/base/abci/abcIfif.c
......@@ -19,6 +19,7 @@
***********************************************************************/
#include "src/base/abc/abc.h"
#include "src/map/if/if.h"
ABC_NAMESPACE_IMPL_START
......@@ -26,28 +27,29 @@ ABC_NAMESPACE_IMPL_START
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
#define IFIF_MAX_LEAVES 6
typedef struct Abc_IffObj_t_ Abc_IffObj_t;
struct Abc_IffObj_t_
{
int Delay0; // separate delay
int Delay1; // combined delay
int nLeaves;
int pLeaves[6];
float Delay[IFIF_MAX_LEAVES+1]; // separate delay
// int nLeaves;
// int pLeaves[IFIF_MAX_LEAVES];
};
typedef struct Abc_IffMan_t_ Abc_IffMan_t;
struct Abc_IffMan_t_
{
Abc_Ntk_t * pNtk;
int nObjs;
int nDelayLut;
int nDegree;
int fVerbose;
Ifif_Par_t * pPars;
// internal data
int nObjs;
Abc_IffObj_t * pObjs;
};
static inline Abc_IffObj_t * Abc_IffObj( Abc_IffMan_t * p, int i ) { assert( i >= 0 && i < p->nObjs ); return p->pObjs + i; }
static inline float Abc_IffDelay( Abc_IffMan_t * p, Abc_Obj_t * pObj, int fDelay1 ) { return Abc_IffObj(p, Abc_ObjId(pObj))->Delay[fDelay1]; }
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
......@@ -64,16 +66,14 @@ static inline Abc_IffObj_t * Abc_IffObj( Abc_IffMan_t * p, int i ) { asser
SeeAlso []
***********************************************************************/
Abc_IffMan_t * Abc_NtkIfifStart( Abc_Ntk_t * pNtk, int nDelayLut, int nDegree, int fVerbose )
Abc_IffMan_t * Abc_NtkIfifStart( Abc_Ntk_t * pNtk, Ifif_Par_t * pPars )
{
Abc_IffMan_t * p;
p = ABC_CALLOC( Abc_IffMan_t, 1 );
p->pNtk = pNtk;
p->nObjs = Abc_NtkObjNumMax( pNtk );
p->nDelayLut = nDelayLut;
p->nDegree = nDegree;
p->fVerbose = fVerbose;
p->pPars = pPars;
// internal data
p->nObjs = Abc_NtkObjNumMax( pNtk );
p->pObjs = ABC_CALLOC( Abc_IffObj_t, p->nObjs );
return p;
}
......@@ -84,10 +84,9 @@ void Abc_NtkIfifStop( Abc_IffMan_t * p )
ABC_FREE( p );
}
/**Function*************************************************************
Synopsis [Compare nodes by Delay1 stored in pObj->iTemp.]
Synopsis [Collects fanins into ppNodes in decreasing order.]
Description []
......@@ -96,17 +95,34 @@ void Abc_NtkIfifStop( Abc_IffMan_t * p )
SeeAlso []
***********************************************************************/
int Abc_ObjIfifCompare( Abc_Obj_t ** pp1, Abc_Obj_t ** pp2 )
void Abc_ObjSortByDelay( Abc_IffMan_t * p, Abc_Obj_t * pObj, int fDelay1, Abc_Obj_t ** ppNodes )
{
Abc_Obj_t * pObj1 = *pp1;
Abc_Obj_t * pObj2 = *pp2;
assert( Abc_ObjIsNode(pObj1) && Abc_ObjIsNode(pObj2) );
return (int)pObj2->iTemp - (int)pObj1->iTemp;
Abc_Obj_t * pFanin;
int i, a, k = 0;
Abc_ObjForEachFanin( pObj, pFanin, i )
{
ppNodes[k++] = pFanin;
if ( Abc_ObjIsCi(pFanin) )
continue;
for ( a = k-1; a > 0; a-- )
if ( Abc_IffDelay(p, ppNodes[a-1], fDelay1) + p->pPars->pLutDelays[a-1] < Abc_IffDelay(p, ppNodes[a], fDelay1) + p->pPars->pLutDelays[a] )
ABC_SWAP( Abc_Obj_t *, ppNodes[a-1], ppNodes[a] );
}
/*
for ( a = 1; a < k; a++ )
{
float D1 = Abc_IffDelay(p, ppNodes[a-1], fDelay1);
float D2 = Abc_IffDelay(p, ppNodes[a], fDelay1);
if ( Abc_ObjIsCi(ppNodes[a-1]) || Abc_ObjIsCi(ppNodes[a]) )
continue;
assert( Abc_IffDelay(p, ppNodes[a-1], fDelay1) + p->pPars->pLutDelays[a-1] >= Abc_IffDelay(p, ppNodes[a], fDelay1) + p->pPars->pLutDelays[a] - 0.01 );
}
*/
}
/**Function*************************************************************
Synopsis [This is the delay which object may have all by itself.]
Synopsis [This is the delay which object has all by itself.]
Description [This delay is stored in Delay0.]
......@@ -115,86 +131,114 @@ int Abc_ObjIfifCompare( Abc_Obj_t ** pp1, Abc_Obj_t ** pp2 )
SeeAlso []
***********************************************************************/
int Abc_ObjDelay0( Abc_IffMan_t * p, Abc_Obj_t * pObj )
float Abc_ObjDelay0( Abc_IffMan_t * p, Abc_Obj_t * pObj )
{
Abc_Obj_t * pFanin;
int i, Delay0 = 0;
Abc_ObjForEachFanin( pObj, pFanin, i )
Delay0 = Abc_MaxInt( Delay0, Abc_IffObj(p, Abc_ObjId(pFanin))->Delay1 );
return p->nDelayLut + Delay0;
int i;
float Delay0 = 0;
Abc_Obj_t * ppNodes[6];
Abc_ObjSortByDelay( p, pObj, 1, ppNodes );
for ( i = 0; i < Abc_ObjFaninNum(pObj); i++ )
Delay0 = Abc_MaxFloat( Delay0, Abc_IffDelay(p, ppNodes[i], 1) + p->pPars->pLutDelays[i] );
return Delay0;
}
/**Function*************************************************************
Synopsis [This is the delay object may have in a group.]
Synopsis [This is the delay object has in the structure.]
Description [This delay is stored in Delay1 and pObj->iTemp.]
Description [This delay is stored in Delay1.]
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_ObjDelay1( Abc_IffMan_t * p, Abc_Obj_t * pObj )
float Abc_ObjDelay1( Abc_IffMan_t * p, Abc_Obj_t * pObj )
{
Abc_IffObj_t * pIfif;
Abc_Obj_t * pNodes[6], * pFanin;
int i, nNodes, Delay1, DelayWorst;
int i, fVeryVerbose = 0;
// Abc_IffObj_t * pIfif = Abc_IffObj( p, Abc_ObjId(pObj) );
Abc_Obj_t * ppNodes[6];
float Delay1, DelayNew;
// find the object structure
pIfif = Abc_IffObj( p, Abc_ObjId(pObj) );
if ( Abc_ObjFaninNum(pObj) == 0 )
return 0;
// collect relevant nodes
nNodes = 0;
Abc_ObjForEachFanin( pObj, pFanin, i )
if ( Abc_ObjIsNode(pFanin) )
{
assert( pFanin->iTemp >= p->nDelayLut );
pNodes[nNodes++] = pFanin;
}
// process the result
Delay1 = 0;
pIfif->nLeaves = 0;
if ( nNodes > 0 )
{
int fVerbose = 0;
// sort fanins by delay
qsort( (void *)pNodes, nNodes, sizeof(Abc_Obj_t *), (int (*)(const void *, const void *)) Abc_ObjIfifCompare );
assert( pNodes[0]->iTemp >= pNodes[nNodes-1]->iTemp );
// sort fanins by delay1+LutDelay
Abc_ObjSortByDelay( p, pObj, 1, ppNodes );
if ( fVerbose )
// print verbose results
if ( fVeryVerbose )
{
for ( i = 0; i < nNodes; i++ )
printf( "Object %d Level %d\n", Abc_ObjId(pObj), Abc_ObjLevel(pObj) );
for ( i = 0; i < Abc_ObjFaninNum(pObj); i++ )
{
printf( "Fanin %d : ", i );
printf( "D0 %4d ", Abc_IffObj(p, Abc_ObjId(pNodes[i]))->Delay0 );
printf( "D0* %4d ", Abc_IffObj(p, Abc_ObjId(pNodes[0]))->Delay0 - (p->nDelayLut-1) );
printf( "D1 %4d ", Abc_IffObj(p, Abc_ObjId(pNodes[i]))->Delay1 );
printf( "D0 %3.2f ", Abc_IffDelay(p, ppNodes[i], 0) );
printf( "D0* %3.2f ", Abc_IffDelay(p, ppNodes[i], 0) + p->pPars->pLutDelays[i] - p->pPars->DelayWire );
printf( "D1 %3.2f", Abc_IffDelay(p, ppNodes[i], 1) + p->pPars->pLutDelays[i] );
printf( "\n" );
}
printf( "\n" );
}
// get the worst-case fanin delay
// DelayWorst = Abc_IffObj(p, Abc_ObjId(pNodes[0]))->Delay0 - (p->nDelayLut-1);
DelayWorst = -1;
// find the delay and remember fanins
for ( i = 0; i < nNodes; i++ )
/*
// for the first nDegree delays, sort them by the minimum Delay1+LutDelay and Delay0-Wire+LutDelay
Delay1 = 0;
pIfif->nLeaves = 0;
for ( i = 0; i < Abc_ObjFaninNum(pObj); i++ )
{
if ( pIfif->nLeaves < p->nDegree && Abc_IffObj(p, Abc_ObjId(pNodes[i]))->Delay1 > DelayWorst )
if ( Abc_ObjIsNode(ppNodes[i]) && pIfif->nLeaves < p->pPars->nDegree )
{
Delay1 = Abc_MaxInt( Delay1, Abc_IffObj(p, Abc_ObjId(pNodes[i]))->Delay0 - (p->nDelayLut-1) );
pIfif->pLeaves[pIfif->nLeaves++] = Abc_ObjId(pNodes[i]);
DelayNew = Abc_MinFloat( Abc_IffDelay(p, ppNodes[i], 1) + p->pPars->pLutDelays[i],
Abc_IffDelay(p, ppNodes[i], 0) + p->pPars->pLutDelays[i] - p->pPars->DelayWire );
pIfif->pLeaves[pIfif->nLeaves++] = Abc_ObjId(ppNodes[i]);
}
else
DelayNew = Abc_IffDelay(p, ppNodes[i], 1) + p->pPars->pLutDelays[i];
Delay1 = Abc_MaxFloat( Delay1, DelayNew );
}
*/
// for the first nDegree delays, sort them by the minimum Delay1+LutDelay and Delay0-Wire+LutDelay
Delay1 = 0;
for ( i = 0; i < Abc_ObjFaninNum(pObj); i++ )
{
if ( i < p->pPars->nDegree )
DelayNew = Abc_MinFloat( Abc_IffDelay(p, ppNodes[i], 1) + p->pPars->pLutDelays[i],
Abc_IffDelay(p, ppNodes[i], 0) + p->pPars->pLutDelays[i] - p->pPars->DelayWire );
else
Delay1 = Abc_MaxInt( Delay1, Abc_IffObj(p, Abc_ObjId(pNodes[i]))->Delay1 );
DelayNew = Abc_IffDelay(p, ppNodes[i], 1) + p->pPars->pLutDelays[i];
Delay1 = Abc_MaxFloat( Delay1, DelayNew );
}
// assert( pIfif->nLeaves > 0 );
assert( Delay1 > 0 );
return Delay1;
}
/**Function*************************************************************
Synopsis [This is the delay which object has all by itself.]
Description [This delay is stored in Delay0.]
SideEffects []
SeeAlso []
***********************************************************************/
float Abc_ObjDelayDegree( Abc_IffMan_t * p, Abc_Obj_t * pObj, int d )
{
int i;
float Delay0 = 0, DelayNew;
Abc_Obj_t * ppNodes[6];
assert( d >= 0 && d <= p->pPars->nDegree );
Abc_ObjSortByDelay( p, pObj, p->pPars->nDegree, ppNodes );
for ( i = 0; i < Abc_ObjFaninNum(pObj); i++ )
{
DelayNew = Abc_IffDelay(p, ppNodes[i], p->pPars->nDegree) + p->pPars->pLutDelays[i];
if ( i == 0 && d > 0 )
DelayNew = Abc_MinFloat(DelayNew, Abc_IffDelay(p, ppNodes[i], d-1) + p->pPars->pLutDelays[i] - p->pPars->DelayWire );
Delay0 = Abc_MaxFloat( Delay0, DelayNew );
}
return p->nDelayLut + Delay1;
return Delay0;
}
/**Function*************************************************************
......@@ -208,26 +252,36 @@ int Abc_ObjDelay1( Abc_IffMan_t * p, Abc_Obj_t * pObj )
SeeAlso []
***********************************************************************/
void Abc_NtkPerformIfif( Abc_Ntk_t * pNtk, int nDelayLut, int nDegree, int fVerbose )
void Abc_NtkPerformIfif( Abc_Ntk_t * pNtk, Ifif_Par_t * pPars )
{
Abc_IffMan_t * p;
Abc_IffObj_t * pIffObj;
Vec_Ptr_t * vNodes;
Abc_Obj_t * pObj;
int i, Delay, nLutSize = Abc_NtkGetFaninMax( pNtk );
if ( nLutSize > 6 )
{
printf( "LUT size (%d) is more than 6.\n", nLutSize );
return;
}
float Delay, Delay10, DegreeFinal;
int i, d, Count10;
assert( pPars->pLutLib->LutMax >= 0 && pPars->pLutLib->LutMax <= IFIF_MAX_LEAVES );
assert( pPars->nLutSize >= 0 && pPars->nLutSize <= IFIF_MAX_LEAVES );
assert( pPars->nDegree >= 0 && pPars->nDegree <= IFIF_MAX_LEAVES );
// convert to AIGs
Abc_NtkToAig( pNtk );
Abc_NtkLevel( pNtk );
assert( nDegree >= 0 && nDegree <= 6 );
// print parameters
if ( pPars->fVerbose )
{
printf( "Running mapper into LUT structures with the following parameters:\n" );
printf( "Pin+Wire: {" );
for ( i = 0; i < pPars->pLutLib->LutMax; i++ )
printf( " %3.2f", pPars->pLutDelays[i] );
printf( " } " );
printf( "Wire %3.2f Degree %d Type: %s\n",
pPars->DelayWire, pPars->nDegree, pPars->fCascade? "Cascade" : "Cluster" );
}
// start manager
p = Abc_NtkIfifStart( pNtk, nDelayLut, nDegree, fVerbose );
// printf( "Running experiment with LUT delay %d and degree %d (LUT size is %d).\n", nDelayLut, nDegree, nLutSize );
p = Abc_NtkIfifStart( pNtk, pPars );
// printf( "Running experiment with LUT delay %d and degree %d (LUT size is %d).\n", DelayWire, nDegree, nLutSize );
// compute the delay
vNodes = Abc_NtkDfs( pNtk, 0 );
......@@ -235,21 +289,50 @@ void Abc_NtkPerformIfif( Abc_Ntk_t * pNtk, int nDelayLut, int nDegree, int fVerb
{
assert( Abc_ObjIsNode(pObj) );
pIffObj = Abc_IffObj( p, Abc_ObjId(pObj) );
pIffObj->Delay0 = Abc_ObjDelay0( p, pObj );
pIffObj->Delay1 = Abc_ObjDelay1( p, pObj );
pObj->iTemp = pIffObj->Delay1;
// printf( "Node %3d : Lev =%3d Delay0 =%4d Delay1 =%4d Leaves =%3d.\n",
// Abc_ObjId(pObj), Abc_ObjLevel(pObj), pIffObj->Delay0, pIffObj->Delay1, pIffObj->nLeaves );
if ( pPars->fCascade )
{
for ( d = 0; d <= pPars->nDegree; d++ )
pIffObj->Delay[d] = Abc_ObjDelayDegree( p, pObj, d );
}
else
{
pIffObj->Delay[0] = Abc_ObjDelay0( p, pObj );
pIffObj->Delay[1] = Abc_ObjDelay1( p, pObj );
}
}
// get final degree number
if ( pPars->fCascade )
DegreeFinal = pPars->nDegree;
else
DegreeFinal = 1;
if ( p->pPars->fVeryVerbose )
Vec_PtrForEachEntry( Abc_Obj_t *, vNodes, pObj, i )
{
printf( "Node %3d : Lev =%3d ", Abc_ObjId(pObj), Abc_ObjLevel(pObj) );
for ( d = 0; d <= DegreeFinal; d++ )
printf( "Del%d =%4.2f ", d, Abc_IffDelay(p, pObj, d) );
printf( "\n" );
}
Vec_PtrFree( vNodes );
// consider delay at the outputs
Delay = 0;
Abc_NtkForEachCo( pNtk, pObj, i )
Delay = Abc_MaxInt( Delay, Abc_IffObj(p, Abc_ObjId(Abc_ObjFanin0(pObj)))->Delay1 );
Delay = Abc_MaxFloat( Delay, Abc_IffDelay(p, Abc_ObjFanin0(pObj), DegreeFinal) );
Delay10 = 0.9 * Delay;
// consider delay at the outputs
Count10 = 0;
Abc_NtkForEachCo( pNtk, pObj, i )
if ( Abc_IffDelay(p, Abc_ObjFanin0(pObj), DegreeFinal) >= Delay10 )
Count10++;
printf( "Critical delay is %5d (%7.2f).\n", Delay, 1.0 * Delay / nDelayLut );
printf( "Critical delay %5.2f. Critical outputs %5.2f %%\n", Delay, 100.0 * Count10 / Abc_NtkCoNum(pNtk) );
// printf( "%.2f %.2f\n", Delay, 100.0 * Count10 / Abc_NtkCoNum(pNtk) );
// derive a new network
......
src/map/if/if.h
......@@ -74,6 +74,19 @@ typedef struct If_Obj_t_ If_Obj_t;
typedef struct If_Cut_t_ If_Cut_t;
typedef struct If_Set_t_ If_Set_t;
typedef struct Ifif_Par_t_ Ifif_Par_t;
struct Ifif_Par_t_
{
int nLutSize; // the LUT size
If_Lib_t * pLutLib; // the LUT library
float pLutDelays[IF_MAX_LUTSIZE]; // pin-to-pin delays of the max LUT
float DelayWire; // wire delay
int nDegree; // structure degree
int fCascade; // cascade
int fVerbose; // verbose
int fVeryVerbose; // verbose
};
// parameters
struct If_Par_t_
{
......
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