path: root/src/aig/miniaig/ndr.h

/**CFile****************************************************************

  FileName    [ndr.h]

  SystemName  [ABC: Logic synthesis and verification system.]

  PackageName [Format for word-level design representation.]

  Synopsis    [External declarations.]

  Author      [Alan Mishchenko]
  
  Affiliation [UC Berkeley]

  Date        [Ver. 1.0. Started - August 22, 2014.]

  Revision    [$Id: ndr.h,v 1.00 2014/09/12 00:00:00 alanmi Exp $]

***********************************************************************/

#ifndef ABC__base__ndr__ndr_h
#define ABC__base__ndr__ndr_h


////////////////////////////////////////////////////////////////////////
///                          INCLUDES                                ///
////////////////////////////////////////////////////////////////////////

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

#include "abcOper.h"

ABC_NAMESPACE_HEADER_START 

#ifdef _WIN32
#define inline __inline
#endif

/*
    For the lack of a better name, this format is called New Data Representation (NDR).

    NDR is designed as an interchange format to pass hierarchical word-level designs between the tools.
    It is relatively simple, uses little memory, and can be easily converted into other ABC data-structures.

    This tutorial discusses how to construct the NDR representation of a hierarchical word-level design.

    First, all names used in the design (including the design name, module names, port names, net names, 
    instance names, etc) are hashed into 1-based integers called "name IDs". Nets are not explicitly represented. 
    The connectivity of a design object is established by specifying name IDs of the nets connected to the object. 
    Object inputs are name IDs of the driving nets; object outputs are name IDs of the driven nets.

    The design is initialized using procedure Ndr_Create(), which takes the design name as an argument.
    A module in the design is initialized using procedure Ndr_AddModule(), which takes the design and 
    the module name as arguments. Objects are added to a module in any order using procedure Ndr_AddObject().

    Primary input and primary output objects should be explicitly created, as shown in the examples below.

    Instances of known operators listed in file "abcOper.h" are assumed to have one output. The only known 
    issue due to this restriction concerns the adder, which produces the sum and the carry-out. To make sure the 
    adder instance has only one output, the carry-out has to be concatenated with the sum before the adder 
    instance is created in the NDR format.

    Instances of hierarchical modules defined by the user can have multiple outputs. 

    Bit-slice and concatenation operators should be represented as separate objects.

    If the ordering of inputs/outputs/flops of a module is not provided as a separate record in NDR format, 
    their ordering is determined by the order of their appearance in the NDR description of the module.

    If left limit and right limit of a bit-range are equal, it is assumed that the range contains one bit
    
    Word-level constants are represented as char-strings given in the same way as they would appear in a Verilog 
    file. For example, the 16-bit constant 10 is represented as a string "4'b1010" and is given as an argument 
    (char * pFunction) to the procedure Ndr_AddObject().

    Currently two types of flops are supported: a simple flop with implicit clock and two fanins (data and init) 
    and a complex flop with 8 fanins (clock, data, reset, set, enable, async, sre, init), as shown in the examples below.

    The initial value of a flop is represented by input "init", which can be driven by a constant or by a primary 
    input of the module. If it is a primary input, is it assumed that the flop is not initialized. If the input 
    "init" is not driven, it is assumed that the flop is initialized to 0.

    Memory read and write ports are supported, as shown in the example below.

    (to be continued)
*/

////////////////////////////////////////////////////////////////////////
///                         PARAMETERS                               ///
////////////////////////////////////////////////////////////////////////

// record types
typedef enum {
    NDR_NONE = 0,          // 0:  unused
    NDR_DESIGN,            // 1:  design (or library of modules)
    NDR_MODULE,            // 2:  one module
    NDR_OBJECT,            // 3:  object
    NDR_INPUT,             // 4:  input
    NDR_OUTPUT,            // 5:  output
    NDR_OPERTYPE,          // 6:  operator type (buffer, shifter, adder, etc)
    NDR_NAME,              // 7:  name
    NDR_RANGE,             // 8:  bit range
    NDR_FUNCTION,          // 9:  specified for some operators (PLAs, etc)
    NDR_TARGET,            // 10: target
    NDR_UNKNOWN            // 11: unknown
} Ndr_RecordType_t; 


////////////////////////////////////////////////////////////////////////
///                         BASIC TYPES                              ///
////////////////////////////////////////////////////////////////////////

// this is an internal procedure, which is not seen by the user
typedef struct Ndr_Data_t_  Ndr_Data_t;
struct Ndr_Data_t_ 
{
    int                     nSize;
    int                     nCap;
    unsigned char *         pHead;
    unsigned int *          pBody;
};

static inline int           Ndr_DataType( Ndr_Data_t * p, int i )                { assert( p->pHead[i] ); return (int)p->pHead[i];                }
static inline int           Ndr_DataSize( Ndr_Data_t * p, int i )                { return Ndr_DataType(p, i) > NDR_OBJECT ? 1 : p->pBody[i];      }
static inline int           Ndr_DataEntry( Ndr_Data_t * p, int i )               { return (int)p->pBody[i];                                       }
static inline int *         Ndr_DataEntryP( Ndr_Data_t * p, int i )              { return (int *)p->pBody + i;                                    }
static inline int           Ndr_DataEnd( Ndr_Data_t * p, int i )                 { return i + p->pBody[i];                                        }
static inline void          Ndr_DataAddTo( Ndr_Data_t * p, int i, int Add )      { assert(Ndr_DataType(p, i) <= NDR_OBJECT); p->pBody[i] += Add;  } 
static inline void          Ndr_DataPush( Ndr_Data_t * p, int Type, int Entry )  { p->pHead[p->nSize] = Type; p->pBody[p->nSize++] = Entry;       }

#define NDR_ALLOC(type, num)     ((type *) malloc(sizeof(type) * (size_t)(num)))

////////////////////////////////////////////////////////////////////////
///                          ITERATORS                               ///
////////////////////////////////////////////////////////////////////////

// iterates over modules in the design
#define Ndr_DesForEachMod( p, Mod )                                   \
    for ( Mod = 1; Mod < Ndr_DataEntry(p, 0); Mod += Ndr_DataSize(p, Mod) ) if (Ndr_DataType(p, Mod) != NDR_MODULE) {} else

// iterates over objects in a module
#define Ndr_ModForEachObj( p, Mod, Obj )                              \
    for ( Obj = Mod + 1; Obj < Ndr_DataEnd(p, Mod); Obj += Ndr_DataSize(p, Obj) ) if (Ndr_DataType(p, Obj) != NDR_OBJECT) {} else

// iterates over records in an object
#define Ndr_ObjForEachEntry( p, Obj, Ent )                            \
    for ( Ent = Obj + 1; Ent < Ndr_DataEnd(p, Obj); Ent += Ndr_DataSize(p, Ent) )

// iterates over primary inputs of a module
#define Ndr_ModForEachPi( p, Mod, Obj )                               \
    Ndr_ModForEachObj( p, Mod, Obj ) if ( !Ndr_ObjIsType(p, Obj, ABC_OPER_CI) ) {} else

// iteraots over primary outputs of a module
#define Ndr_ModForEachPo( p, Mod, Obj )                               \
    Ndr_ModForEachObj( p, Mod, Obj ) if ( !Ndr_ObjIsType(p, Obj, ABC_OPER_CO) ) {} else

// iterates over internal nodes of a module
#define Ndr_ModForEachNode( p, Mod, Obj )                             \
    Ndr_ModForEachObj( p, Mod, Obj ) if ( Ndr_ObjIsType(p, Obj, ABC_OPER_CI) || Ndr_ObjIsType(p, Obj, ABC_OPER_CO) ) {} else

// iterates over target signals of a module
#define Ndr_ModForEachTarget( p, Mod, Obj )                           \
    for ( Obj = Mod + 1; Obj < Ndr_DataEnd(p, Mod); Obj += Ndr_DataSize(p, Obj) ) if (Ndr_DataType(p, Obj) != NDR_TARGET) {} else

////////////////////////////////////////////////////////////////////////
///                    INTERNAL PROCEDURES                           ///
////////////////////////////////////////////////////////////////////////


static inline void Ndr_DataResize( Ndr_Data_t * p, int Add )
{
    if ( p->nSize + Add <= p->nCap )
        return;
    p->nCap  = 2 * p->nCap > p->nSize + Add ? 2 * p->nCap : p->nSize + Add;
    p->pHead = (unsigned char*)realloc( p->pHead,   p->nCap );
    p->pBody = (unsigned int *)realloc( p->pBody, 4*p->nCap );
}
static inline void Ndr_DataPushRange( Ndr_Data_t * p, int RangeLeft, int RangeRight, int fSignedness )
{ 
    if ( fSignedness )
    {
        Ndr_DataPush( p, NDR_RANGE, RangeLeft );
        Ndr_DataPush( p, NDR_RANGE, RangeRight );
        Ndr_DataPush( p, NDR_RANGE, fSignedness );
        return;
    }
    if ( !RangeLeft && !RangeRight )
        return;
    if ( RangeLeft == RangeRight )
        Ndr_DataPush( p, NDR_RANGE, RangeLeft );
    else
    {
        Ndr_DataPush( p, NDR_RANGE, RangeLeft );
        Ndr_DataPush( p, NDR_RANGE, RangeRight );
    }
}
static inline void Ndr_DataPushArray( Ndr_Data_t * p, int Type, int nArray, int * pArray )
{ 
    if ( !nArray )
        return;
    assert( nArray > 0 );
    Ndr_DataResize( p, nArray );
    memset( p->pHead + p->nSize, Type, (size_t)nArray );
    memcpy( p->pBody + p->nSize, pArray, (size_t)4*nArray );
    p->nSize += nArray;
}
static inline void Ndr_DataPushString( Ndr_Data_t * p, int ObjType, int Type, char * pFunc )
{ 
    int nBuffInts;
    int * pBuff;
    if ( !pFunc )
        return;
    if ( ObjType == ABC_OPER_LUT )
    {
        word Truth = (word)pFunc;
        Ndr_DataPushArray( p, Type, 2, (int *)&Truth );
    }
    else
    {
        nBuffInts = ((int)strlen(pFunc) + 4) / 4;
        pBuff = (int *)calloc( 1, 4*nBuffInts );
        memcpy( pBuff, pFunc, strlen(pFunc) );
        Ndr_DataPushArray( p, Type, nBuffInts, pBuff );
        free( pBuff );
    }
}

////////////////////////////////////////////////////////////////////////
///                     VERILOG WRITING                              ///
////////////////////////////////////////////////////////////////////////

static inline int Ndr_ObjReadEntry( Ndr_Data_t * p, int Obj, int Type )
{
    int Ent;
    Ndr_ObjForEachEntry( p, Obj, Ent )
        if ( Ndr_DataType(p, Ent) == Type )
            return Ndr_DataEntry(p, Ent);
    return -1;
}
static inline int Ndr_ObjReadArray( Ndr_Data_t * p, int Obj, int Type, int ** ppStart )
{
    int Ent, Counter = 0; *ppStart = NULL;
    Ndr_ObjForEachEntry( p, Obj, Ent )
        if ( Ndr_DataType(p, Ent) == Type )
        {
            Counter++;
            if ( *ppStart == NULL )
                *ppStart = (int *)p->pBody + Ent;
        }
        else if ( *ppStart )
            return Counter;
    return Counter;
} 
static inline int Ndr_ObjIsType( Ndr_Data_t * p, int Obj, int Type )
{
    int Ent;
    Ndr_ObjForEachEntry( p, Obj, Ent )
        if ( Ndr_DataType(p, Ent) == NDR_OPERTYPE )
            return (int)(Ndr_DataEntry(p, Ent) == Type);
    return -1;
}
static inline int Ndr_ObjReadBody( Ndr_Data_t * p, int Obj, int Type )
{
    int Ent;
    Ndr_ObjForEachEntry( p, Obj, Ent )
        if ( Ndr_DataType(p, Ent) == Type )
            return Ndr_DataEntry(p, Ent);
    return -1;
}
static inline int * Ndr_ObjReadBodyP( Ndr_Data_t * p, int Obj, int Type )
{
    int Ent;
    Ndr_ObjForEachEntry( p, Obj, Ent )
        if ( Ndr_DataType(p, Ent) == Type )
            return Ndr_DataEntryP(p, Ent);
    return NULL;
}
static inline void Ndr_ObjWriteRange( Ndr_Data_t * p, int Obj, FILE * pFile, int fSkipBin )
{
    int * pArray, nArray = Ndr_ObjReadArray( p, Obj, NDR_RANGE, &pArray );
    if ( (nArray == 0 || nArray == 1) && fSkipBin )
        return;
    if ( nArray == 3 && fSkipBin )
        fprintf( pFile, "signed " ); 
    else if ( nArray == 1 )
    {
        if ( fSkipBin )
            fprintf( pFile, "[%d:%d]", pArray[0], pArray[0] );
        else
            fprintf( pFile, "[%d]", pArray[0] );
    }
    else if ( nArray == 0 )
    {
        if ( fSkipBin )
            fprintf( pFile, "[%d:%d]", 0, 0 );
        else
            fprintf( pFile, "[%d]", 0 );
    }
    else
        fprintf( pFile, "[%d:%d]", pArray[0], pArray[1] );
}
static inline char * Ndr_ObjReadOutName( Ndr_Data_t * p, int Obj, char ** pNames )
{
    return pNames[Ndr_ObjReadBody(p, Obj, NDR_OUTPUT)];
}
static inline char * Ndr_ObjReadInName( Ndr_Data_t * p, int Obj, char ** pNames )
{
    return pNames[Ndr_ObjReadBody(p, Obj, NDR_INPUT)];
}

static inline int Ndr_DataCiNum( Ndr_Data_t * p, int Mod )
{ 
    int Obj, Count = 0;
    Ndr_ModForEachPi( p, Mod, Obj )
        Count++;
    return Count;
}
static inline int Ndr_DataCoNum( Ndr_Data_t * p, int Mod )
{ 
    int Obj, Count = 0;
    Ndr_ModForEachPo( p, Mod, Obj )
        Count++;
    return Count;
}
static inline int Ndr_DataObjNum( Ndr_Data_t * p, int Mod )
{ 
    int Obj, Count = 0;
    Ndr_ModForEachObj( p, Mod, Obj )
        Count++;
    return Count;
}

// to write signal names, this procedure takes a mapping of name IDs into actual char-strings (pNames)
static inline void Ndr_WriteVerilogModule( FILE * pFile, void * pDesign, int Mod, char ** pNames, int fSimple )
{
    Ndr_Data_t * p = (Ndr_Data_t *)pDesign; 
    int * pOuts = NDR_ALLOC( int, Ndr_DataCoNum(p, Mod) );
    int i, k, Obj, nArray, * pArray, fFirst = 1;

    fprintf( pFile, "\nmodule %s (\n  ", pNames[Ndr_ObjReadEntry(p, Mod, NDR_NAME)] );

    Ndr_ModForEachPi( p, Mod, Obj )
        fprintf( pFile, "%s, ", Ndr_ObjReadOutName(p, Obj, pNames) );

    fprintf( pFile, "\n  " );

    Ndr_ModForEachPo( p, Mod, Obj )
        fprintf( pFile, "%s%s", fFirst ? "":", ", Ndr_ObjReadInName(p, Obj, pNames) ), fFirst = 0;

    fprintf( pFile, "\n);\n\n" );

    Ndr_ModForEachPi( p, Mod, Obj )
    {
        fprintf( pFile, "  input " );
        Ndr_ObjWriteRange( p, Obj, pFile, 1 );
        fprintf( pFile, " %s;\n", Ndr_ObjReadOutName(p, Obj, pNames) );
    }

    i = 0;
    Ndr_ModForEachPo( p, Mod, Obj )
    {
        fprintf( pFile, "  output " );
        Ndr_ObjWriteRange( p, Obj, pFile, 1 );
        fprintf( pFile, " %s;\n", Ndr_ObjReadInName(p, Obj, pNames) );
        pOuts[i++] = Ndr_ObjReadBody(p, Obj, NDR_INPUT);
    }

    fprintf( pFile, "\n" );

    Ndr_ModForEachNode( p, Mod, Obj )
    {
        for ( k = 0; k < i; k++ )
            if ( pOuts[k] == Ndr_ObjReadBody(p, Obj, NDR_OUTPUT) )
                break;
        if ( k < i )
            continue;
        if ( Ndr_ObjReadOutName(p, Obj, pNames)[0] == '1' )
            continue;
        fprintf( pFile, "  wire " );
        Ndr_ObjWriteRange( p, Obj, pFile, 1 );
        fprintf( pFile, " %s;\n", Ndr_ObjReadOutName(p, Obj, pNames) );
    }
    free( pOuts );

    fprintf( pFile, "\n" );

    Ndr_ModForEachNode( p, Mod, Obj )
    {
        int i, Type = Ndr_ObjReadBody(p, Obj, NDR_OPERTYPE);
        if ( Type >= 256 )
        {
            fprintf( pFile, "  %s ", pNames[Ndr_ObjReadEntry(p, Type-256, NDR_NAME)] );
            if ( Ndr_ObjReadBody(p, Obj, NDR_NAME) > 0 )
                fprintf( pFile, "%s ", pNames[Ndr_ObjReadBody(p, Obj, NDR_NAME)] );
            fprintf( pFile, "( " );
            nArray = Ndr_ObjReadArray( p, Obj, NDR_INPUT, &pArray );
            for ( i = 0; i < nArray; i++ )
                fprintf( pFile, "%s%s ", pNames[pArray[i]], i==nArray-1 ? "":"," );
            fprintf( pFile, ");\n" );
            continue;
        }
        if ( Type == ABC_OPER_DFF )
        {
            fprintf( pFile, "  %s ", "ABC_DFF" );
            if ( Ndr_ObjReadBody(p, Obj, NDR_NAME) > 0 )
                fprintf( pFile, "%s ", pNames[Ndr_ObjReadBody(p, Obj, NDR_NAME)] );
            fprintf( pFile, "( " );
            nArray = Ndr_ObjReadArray( p, Obj, NDR_INPUT, &pArray );
            fprintf( pFile, ".q(%s), ",    Ndr_ObjReadOutName(p, Obj, pNames) );
            fprintf( pFile, ".d(%s), ",    pNames[pArray[0]] );
            fprintf( pFile, ".init(%s) ",  pNames[pArray[1]] );
            fprintf( pFile, ");\n" );
            continue;
        }
        if ( Type == ABC_OPER_DFFRSE )
        {
            fprintf( pFile, "  %s ", "ABC_DFFRSE" );
            if ( Ndr_ObjReadBody(p, Obj, NDR_NAME) > 0 )
                fprintf( pFile, "%s ", pNames[Ndr_ObjReadBody(p, Obj, NDR_NAME)] );
            fprintf( pFile, "( " );
            nArray = Ndr_ObjReadArray( p, Obj, NDR_INPUT, &pArray );
            fprintf( pFile, ".q(%s), ",      Ndr_ObjReadOutName(p, Obj, pNames) );
            fprintf( pFile, ".d(%s), ",      pNames[pArray[0]] );
            fprintf( pFile, ".clk(%s), ",    pNames[pArray[1]] );
            fprintf( pFile, ".reset(%s), ",  pNames[pArray[2]] );
            fprintf( pFile, ".set(%s), ",    pNames[pArray[3]] );
            fprintf( pFile, ".enable(%s), ", pNames[pArray[4]] );
            fprintf( pFile, ".async(%s), ",  pNames[pArray[5]] );
            fprintf( pFile, ".sre(%s), ",    pNames[pArray[6]] );
            fprintf( pFile, ".init(%s) ",    pNames[pArray[7]] );
            fprintf( pFile, ");\n" );
            continue;
        }
        if ( Type == ABC_OPER_RAMR )
        {
            fprintf( pFile, "  %s ", "ABC_READ" );
            if ( Ndr_ObjReadBody(p, Obj, NDR_NAME) > 0 )
                fprintf( pFile, "%s ", pNames[Ndr_ObjReadBody(p, Obj, NDR_NAME)] );
            fprintf( pFile, "( " );
            nArray = Ndr_ObjReadArray( p, Obj, NDR_INPUT, &pArray );
            fprintf( pFile, ".data(%s), ",   Ndr_ObjReadOutName(p, Obj, pNames) );
            fprintf( pFile, ".mem_in(%s), ", pNames[pArray[0]] );
            fprintf( pFile, ".addr(%s) ",    pNames[pArray[1]] );
            fprintf( pFile, ");\n" );
            continue;
        }
        if ( Type == ABC_OPER_RAMW )
        {
            fprintf( pFile, "  %s ", "ABC_WRITE" );
            if ( Ndr_ObjReadBody(p, Obj, NDR_NAME) > 0 )
                fprintf( pFile, "%s ", pNames[Ndr_ObjReadBody(p, Obj, NDR_NAME)] );
            fprintf( pFile, "( " );
            nArray = Ndr_ObjReadArray( p, Obj, NDR_INPUT, &pArray );
            fprintf( pFile, ".mem_out(%s), ",  Ndr_ObjReadOutName(p, Obj, pNames) );
            fprintf( pFile, ".mem_in(%s), ",   pNames[pArray[0]] );
            fprintf( pFile, ".addr(%s), ",     pNames[pArray[1]] );
            fprintf( pFile, ".data(%s) ",      pNames[pArray[2]] );
            fprintf( pFile, ");\n" );
            continue;
        }
        if ( fSimple )
        {
            if ( Ndr_ObjReadOutName(p, Obj, pNames)[0] == '1' )
                continue;
            nArray = Ndr_ObjReadArray( p, Obj, NDR_INPUT, &pArray );
            fprintf( pFile, "  %s ( %s", Abc_OperNameSimple(Type), Ndr_ObjReadOutName(p, Obj, pNames) );
            if ( nArray == 0 )
                fprintf( pFile, ", %s );\n", (char *)Ndr_ObjReadBodyP(p, Obj, NDR_FUNCTION) );
            else if ( nArray == 1 && Ndr_ObjReadBody(p, Obj, NDR_OPERTYPE) == ABC_OPER_BIT_BUF )
                fprintf( pFile, ", %s );\n", pNames[pArray[0]] );
            else
            {
                for ( i = 0; i < nArray; i++ )
                    fprintf( pFile, ", %s", pNames[pArray[i]] );
                fprintf( pFile, " );\n" );
            }
            continue;
        }
        fprintf( pFile, "  assign %s = ", Ndr_ObjReadOutName(p, Obj, pNames) );
        nArray = Ndr_ObjReadArray( p, Obj, NDR_INPUT, &pArray );
        if ( nArray == 0 )
            fprintf( pFile, "%s;\n", (char *)Ndr_ObjReadBodyP(p, Obj, NDR_FUNCTION) );
        else if ( nArray == 1 && Ndr_ObjReadBody(p, Obj, NDR_OPERTYPE) == ABC_OPER_BIT_BUF )
            fprintf( pFile, "%s;\n", pNames[pArray[0]] );
        else if ( Type == ABC_OPER_SLICE )
            fprintf( pFile, "%s", pNames[pArray[0]] ),
            Ndr_ObjWriteRange( p, Obj, pFile, 0 ),
            fprintf( pFile, ";\n" );
        else if ( Type == ABC_OPER_CONCAT )
        {
            fprintf( pFile, "{" );
            for ( i = 0; i < nArray; i++ )
                fprintf( pFile, "%s%s", pNames[pArray[i]], i==nArray-1 ? "":", " );
            fprintf( pFile, "};\n" );
        }
        else if ( nArray == 1 )
            fprintf( pFile, "%s %s;\n", Abc_OperName(Ndr_ObjReadBody(p, Obj, NDR_OPERTYPE)), pNames[pArray[0]] );
        else if ( nArray == 2 )
            fprintf( pFile, "%s %s %s;\n", pNames[pArray[0]], Abc_OperName(Ndr_ObjReadBody(p, Obj, NDR_OPERTYPE)), pNames[pArray[1]] );
        else if ( nArray == 3 && Type == ABC_OPER_ARI_ADD )
            fprintf( pFile, "%s + %s + %s;\n", pNames[pArray[0]], pNames[pArray[1]], pNames[pArray[2]] );
        else if ( Type == ABC_OPER_BIT_MUX )
            fprintf( pFile, "%s ? %s : %s;\n", pNames[pArray[0]], pNames[pArray[1]], pNames[pArray[2]] );
        else
            fprintf( pFile, "<cannot write operation %s>;\n", Abc_OperName(Ndr_ObjReadBody(p, Obj, NDR_OPERTYPE)) );
    }

    fprintf( pFile, "\nendmodule\n\n" );
}

// to write signal names, this procedure takes a mapping of name IDs into actual char-strings (pNames)
static inline void Ndr_WriteVerilog( char * pFileName, void * pDesign, char ** pNames, int fSimple )
{
    Ndr_Data_t * p = (Ndr_Data_t *)pDesign; int Mod;

    FILE * pFile = pFileName ? fopen( pFileName, "wb" ) : stdout;
    if ( pFile == NULL ) { printf( "Cannot open file \"%s\" for writing.\n", pFileName ? pFileName : "stdout" ); return; }

    Ndr_DesForEachMod( p, Mod )
        Ndr_WriteVerilogModule( pFile, p, Mod, pNames, fSimple );
    
    if ( pFileName ) fclose( pFile );
}


////////////////////////////////////////////////////////////////////////
///                     EXTERNAL PROCEDURES                          ///
////////////////////////////////////////////////////////////////////////

// creating a new module (returns pointer to the memory buffer storing the module info)
static inline void * Ndr_Create( int Name )
{
    Ndr_Data_t * p = NDR_ALLOC( Ndr_Data_t, 1 );
    p->nSize = 0;
    p->nCap  = 16;
    p->pHead = NDR_ALLOC( unsigned char, p->nCap );
    p->pBody = NDR_ALLOC( unsigned int, p->nCap * 4 );
    Ndr_DataPush( p, NDR_DESIGN, 0 );
    Ndr_DataPush( p, NDR_NAME, Name );
    Ndr_DataAddTo( p, 0, p->nSize );
    assert( p->nSize == 2 );
    assert( Name );
    return p;
}

// creating a new module in an already started design 
// returns module ID to be used when adding objects to the module
static inline int Ndr_AddModule( void * pDesign, int Name )
{
    Ndr_Data_t * p = (Ndr_Data_t *)pDesign;
    int Mod = p->nSize;  
    Ndr_DataResize( p, 6 );
    Ndr_DataPush( p, NDR_MODULE, 0 );
    Ndr_DataPush( p, NDR_NAME, Name );
    Ndr_DataAddTo( p, Mod, p->nSize - Mod );
    Ndr_DataAddTo( p, 0, p->nSize - Mod );
    assert( (int)p->pBody[0] == p->nSize );
    return Mod + 256;
}

// adding a new object (input/output/flop/intenal node) to an already started module
// this procedure takes the design, the module ID, and the parameters of the boject
// (please note that all objects should be added to a given module before starting a new module)
static inline void Ndr_AddObject( void * pDesign, int ModuleId,
                                  int ObjType, int InstName, 
                                  int RangeLeft, int RangeRight, int fSignedness, 
                                  int nInputs, int * pInputs, 
                                  int nOutputs, int * pOutputs, 
                                  char * pFunction )
{
    Ndr_Data_t * p = (Ndr_Data_t *)pDesign;
    int Mod = ModuleId - 256;  
    int Obj = p->nSize;  assert( ObjType != 0 );
    Ndr_DataResize( p, 6 );
    Ndr_DataPush( p, NDR_OBJECT, 0 );
    Ndr_DataPush( p, NDR_OPERTYPE, ObjType );
    Ndr_DataPushRange( p, RangeLeft, RangeRight, fSignedness );
    if ( InstName )
        Ndr_DataPush( p, NDR_NAME, InstName );
    Ndr_DataPushArray( p, NDR_INPUT, nInputs, pInputs );
    Ndr_DataPushArray( p, NDR_OUTPUT, nOutputs, pOutputs );
    Ndr_DataPushString( p, ObjType, NDR_FUNCTION, pFunction );
    Ndr_DataAddTo( p, Obj, p->nSize - Obj );
    Ndr_DataAddTo( p, Mod, p->nSize - Obj );
    Ndr_DataAddTo( p, 0, p->nSize - Obj );
    assert( (int)p->pBody[0] == p->nSize );
}

// deallocate the memory buffer
static inline void Ndr_Delete( void * pDesign )
{
    Ndr_Data_t * p = (Ndr_Data_t *)pDesign;
    if ( !p ) return;
    free( p->pHead );
    free( p->pBody );
    free( p );
}


////////////////////////////////////////////////////////////////////////
///                  FILE READING AND WRITING                        ///
////////////////////////////////////////////////////////////////////////

// file reading/writing
static inline void * Ndr_Read( char * pFileName )
{
    Ndr_Data_t * p; int nFileSize, RetValue;
    FILE * pFile = fopen( pFileName, "rb" );
    if ( pFile == NULL ) { printf( "Cannot open file \"%s\" for reading.\n", pFileName ); return NULL; }
    // check file size
    fseek( pFile, 0, SEEK_END );
    nFileSize = ftell( pFile ); 
    if ( nFileSize % 5 != 0 )
        return NULL;
    assert( nFileSize % 5 == 0 );
    rewind( pFile );
    // create structure
    p = NDR_ALLOC( Ndr_Data_t, 1 );
    p->nSize = p->nCap = nFileSize / 5;
    p->pHead = NDR_ALLOC( unsigned char, p->nCap );
    p->pBody = NDR_ALLOC( unsigned int, p->nCap * 4 );
    RetValue = (int)fread( p->pBody, 4, p->nCap, pFile );
    RetValue = (int)fread( p->pHead, 1, p->nCap, pFile );
    assert( p->nSize == (int)p->pBody[0] );
    fclose( pFile );
    //printf( "Read the design from file \"%s\".\n", pFileName );
    return p;
}
static inline void Ndr_Write( char * pFileName, void * pDesign )
{
    Ndr_Data_t * p = (Ndr_Data_t *)pDesign; int RetValue;
    FILE * pFile = fopen( pFileName, "wb" );
    if ( pFile == NULL ) { printf( "Cannot open file \"%s\" for writing.\n", pFileName ? pFileName : "stdout" ); return; }
    RetValue = (int)fwrite( p->pBody, 4, p->pBody[0], pFile );
    RetValue = (int)fwrite( p->pHead, 1, p->pBody[0], pFile );
    fclose( pFile );
    //printf( "Dumped the design into file \"%s\".\n", pFileName );
}


////////////////////////////////////////////////////////////////////////
///                     TESTING PROCEDURE                            ///
////////////////////////////////////////////////////////////////////////

// This testing procedure creates and writes into a Verilog file 
// the following design composed of one module

// module add10 ( input [3:0] a, output [3:0] s );
//   wire [3:0] const10 = 4'b1010;
//   assign s = a + const10;
// endmodule

static inline void Ndr_ModuleTest()
{
    // name IDs
    int NameIdA = 2;
    int NameIdS = 3;
    int NameIdC = 4;
    // array of fanins of node s
    int Fanins[2] = { NameIdA, NameIdC };
    // map name IDs into char strings
    char * ppNames[5] = { NULL, "add10", "a", "s", "const10" };

    // create a new module
    void * pDesign = Ndr_Create( 1 );

    int ModuleID = Ndr_AddModule( pDesign, 1 );

    // add objects to the modele
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   3, 0, 0,   0, NULL,      1, &NameIdA,   NULL      ); // no fanins
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CONST,    0,   3, 0, 0,   0, NULL,      1, &NameIdC,   "4'b1010" ); // no fanins
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_ARI_ADD,  0,   3, 0, 0,   2, Fanins,    1, &NameIdS,   NULL      ); // fanins are a and const10 
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,       0,   3, 0, 0,   1, &NameIdS,  0, NULL,       NULL      ); // fanin is a

    // write Verilog for verification
    Ndr_WriteVerilog( NULL, pDesign, ppNames, 0 );
    Ndr_Write( "add4.ndr", pDesign );
    Ndr_Delete( pDesign );
}



// This testing procedure creates and writes into a Verilog file 
// the following design composed of one adder divided into two

// module add8 ( input [7:0] a, input [7:0] b, output [7:0] s, output co );
//   wire [3:0] a0 = a[3:0];
//   wire [3:0] b0 = b[3:0];

//   wire [7:4] a1 = a[7:4];
//   wire [7:4] b1 = b[7:4];

//   wire [4:0] r0 = a0 + b0;
//   wire [3:0] s0 = r0[3:0];
//   wire rco = r0[4];

//   wire [4:0] r1 = a1 + b1 + rco;
//   wire [3:0] s1 = r1[3:0];
//   assign co = r1[4];

//   assign s = {s1, s0};
// endmodule

static inline void Ndr_ModuleTestAdder()
{
    // map name IDs into char strings
    char * ppNames[20] = {  NULL, 
                           "a", "b", "s", "co",          // 1,  2,  3,  4
                           "a0",  "a1",  "b0",  "b1",    // 5,  6,  7,  8
                           "r0", "s0", "rco",            // 9,  10, 11
                           "r1", "s1", "add8"            // 12, 13, 14
                         };
    // fanins 
    int FaninA        =  1;
    int FaninB        =  2;
    int FaninS        =  3;
    int FaninCO       =  4;

    int FaninA0       =  5;
    int FaninA1       =  6;
    int FaninB0       =  7;
    int FaninB1       =  8;

    int FaninR0       =  9;
    int FaninS0       = 10;
    int FaninRCO      = 11;

    int FaninR1       = 12;
    int FaninS1       = 13;

    int Fanins1[2]    = { FaninA0, FaninB0 };
    int Fanins2[3]    = { FaninA1, FaninB1, FaninRCO };
    int Fanins3[4]    = { FaninS1, FaninS0 };

    // create a new module
    void * pDesign = Ndr_Create( 14 );

    int ModuleID = Ndr_AddModule( pDesign, 14 );

    // add objects to the modele
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   7, 0, 0,   0, NULL,      1, &FaninA,   NULL  );  // no fanins
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   7, 0, 0,   0, NULL,      1, &FaninB,   NULL  );  // no fanins

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SLICE,    0,   3, 0, 0,   1, &FaninA,   1, &FaninA0,   NULL );  // wire [3:0] a0 = a[3:0];
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SLICE,    0,   3, 0, 0,   1, &FaninB,   1, &FaninB0,   NULL );  // wire [3:0] b0 = a[3:0];

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SLICE,    0,   7, 4, 0,   1, &FaninA,   1, &FaninA1,   NULL );  // wire [7:4] a1 = a[7:4];
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SLICE,    0,   7, 4, 0,   1, &FaninB,   1, &FaninB1,   NULL );  // wire [7:4] b1 = b[7:4];

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_ARI_ADD,  0,   4, 0, 0,   2, Fanins1,   1, &FaninR0,   NULL );  // wire [4:0] r0 = a0 + b0;
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SLICE,    0,   3, 0, 0,   1, &FaninR0,  1, &FaninS0,   NULL );  // wire [3:0] s0 = r0[3:0];
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SLICE,    0,   4, 4, 0,   1, &FaninR0,  1, &FaninRCO,  NULL );  // wire rco = r0[4];

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_ARI_ADD,  0,   4, 0, 0,   3, Fanins2,   1, &FaninR1,   NULL );  // wire [4:0] r1 = a1 + b1 + rco;
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SLICE,    0,   3, 0, 0,   1, &FaninR1,  1, &FaninS1,   NULL );  // wire [3:0] s1 = r1[3:0];
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SLICE,    0,   4, 4, 0,   1, &FaninR1,  1, &FaninCO,   NULL );  // assign co = r1[4];

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CONCAT,   0,   7, 0, 0,   2, Fanins3,   1, &FaninS,    NULL );  // s = {s1, s0};

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,       0,   7, 0, 0,   1, &FaninS,   0, NULL,       NULL ); 
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,       0,   0, 0, 0,   1, &FaninCO,  0, NULL,       NULL ); 

    // write Verilog for verification
    Ndr_WriteVerilog( NULL, pDesign, ppNames, 0 );
    Ndr_Write( "add8.ndr", pDesign );
    Ndr_Delete( pDesign );

}

// This testing procedure creates and writes into a Verilog file 
// the following hierarchical design composed of two modules

// module mux21w ( input sel, input [3:0] d1, input [3:0] d0, output [3:0] out );
//   assign out = sel ? d1 : d0;
// endmodule

// module mux41w ( input [1:0] sel, input [15:0] d, output [3:0] out );
//   wire [3:0] t0, t1;
//   wire [3:0] d0 = d[3:0];
//   wire [3:0] d1 = d[7:4];
//   wire [3:0] d2 = d[11:8];
//   wire [3:0] d3 = d[15:12];
//   wire sel0 = sel[0];
//   wire sel1 = sel[1];
//   mux21w i0 ( sel0, d1, d0, t0 );
//   mux21w i1 ( sel0, d3, d2, t1 );
//   mux21w i2 ( sel1, t1, t0, out );
// endmodule

static inline void Ndr_ModuleTestHierarchy()
{
    // map name IDs into char strings
    char * ppNames[20] = {  NULL, 
                           "mux21w", "mux41w",     // 1,  2
                           "sel",  "d",  "out",    // 3,  4,  5
                           "d0", "d1", "d2", "d3", // 6,  7,  8,  9
                           "sel0", "sel1",         // 10, 11,
                           "t0", "t1",             // 12, 13
                           "i0", "i1", "i2"        // 14, 15, 16
                         };
    // fanins 
    int FaninSel      =  3;
    int FaninSel0     = 10;
    int FaninSel1     = 11;
    int FaninD        =  4;
    int FaninD0       =  6;
    int FaninD1       =  7;
    int FaninD2       =  8;
    int FaninD3       =  9;
    int FaninT0       = 12;
    int FaninT1       = 13;
    int FaninOut      =  5;
    int Fanins1[3]    = {  FaninSel,  FaninD1, FaninD0 };
    int Fanins3[3][3] = { {FaninSel0, FaninD1, FaninD0 },  
                          {FaninSel0, FaninD3, FaninD2 },  
                          {FaninSel1, FaninT1, FaninT0 } };

    // create a new module
    void * pDesign = Ndr_Create( 2 );

    int Module21, Module41;

    Module21 = Ndr_AddModule( pDesign, 1 );
    
    Ndr_AddObject( pDesign, Module21, ABC_OPER_CI,        0,   0, 0, 0,   0, NULL,        1, &FaninSel,  NULL ); 
    Ndr_AddObject( pDesign, Module21, ABC_OPER_CI,        0,   3, 0, 0,   0, NULL,        1, &FaninD1,   NULL ); 
    Ndr_AddObject( pDesign, Module21, ABC_OPER_CI,        0,   3, 0, 0,   0, NULL,        1, &FaninD0,   NULL ); 
    Ndr_AddObject( pDesign, Module21, ABC_OPER_BIT_MUX,   0,   3, 0, 0,   3, Fanins1,     1, &FaninOut,  NULL ); 
    Ndr_AddObject( pDesign, Module21, ABC_OPER_CO,        0,   3, 0, 0,   1, &FaninOut,   0, NULL,       NULL ); 

    Module41 = Ndr_AddModule( pDesign, 2 );

    Ndr_AddObject( pDesign, Module41, ABC_OPER_CI,        0,   1, 0, 0,   0, NULL,        1, &FaninSel,  NULL ); 
    Ndr_AddObject( pDesign, Module41, ABC_OPER_CI,        0,   15,0, 0,   0, NULL,        1, &FaninD,    NULL ); 

    Ndr_AddObject( pDesign, Module41, ABC_OPER_SLICE,     0,   3, 0, 0,   1, &FaninD,     1, &FaninD0,   NULL ); 
    Ndr_AddObject( pDesign, Module41, ABC_OPER_SLICE,     0,   7, 4, 0,   1, &FaninD,     1, &FaninD1,   NULL ); 
    Ndr_AddObject( pDesign, Module41, ABC_OPER_SLICE,     0,   11,8, 0,   1, &FaninD,     1, &FaninD2,   NULL ); 
    Ndr_AddObject( pDesign, Module41, ABC_OPER_SLICE,     0,   15,12,0,   1, &FaninD,     1, &FaninD3,   NULL ); 

    Ndr_AddObject( pDesign, Module41, ABC_OPER_SLICE,     0,   0, 0, 0,   1, &FaninSel,   1, &FaninSel0, NULL ); 
    Ndr_AddObject( pDesign, Module41, ABC_OPER_SLICE,     0,   1, 1, 0,   1, &FaninSel,   1, &FaninSel1, NULL ); 

    Ndr_AddObject( pDesign, Module41, Module21,          14,   3, 0, 0,   3, Fanins3[0],  1, &FaninT0,   NULL ); 
    Ndr_AddObject( pDesign, Module41, Module21,          15,   3, 0, 0,   3, Fanins3[1],  1, &FaninT1,   NULL ); 
    Ndr_AddObject( pDesign, Module41, Module21,          16,   3, 0, 0,   3, Fanins3[2],  1, &FaninOut,  NULL ); 
    Ndr_AddObject( pDesign, Module41, ABC_OPER_CO,        0,   3, 0, 0,   1, &FaninOut,   0, NULL,       NULL ); 

    // write Verilog for verification
    Ndr_WriteVerilog( NULL, pDesign, ppNames, 0 );
    Ndr_Write( "mux41w.ndr", pDesign );
    Ndr_Delete( pDesign );
}


// This testing procedure creates and writes into a Verilog file 
// the following design with read/write memory ports

// module test ( input clk, input [8:0] raddr, input [8:0] waddr, input [31:0] data, input [16383:0] mem_init, output out );
// 
//    wire [31:0] read1, read2;
// 
//    wire [16383:0] mem_fo1, mem_fo2,  mem_fi1, mem_fi2;
// 
//    ABC_FF    i_reg1   ( .q(mem_fo1), .d(mem_fi1), .init(mem_init) );
//    ABC_FF    i_reg2   ( .q(mem_fo2), .d(mem_fi2), .init(mem_init) );
// 
//    ABC_WRITE i_write1 ( .mem_out(mem_fi1), .mem_in(mem_fo1), .addr(waddr), .data(data) );
//    ABC_WRITE i_write2 ( .mem_out(mem_fi2), .mem_in(mem_fo2), .addr(waddr), .data(data) );
// 
//    ABC_READ  i_read1  ( .data(read1), .mem_in(mem_fi1), .addr(raddr) );
//    ABC_READ  i_read2  ( .data(read2), .mem_in(mem_fi2), .addr(raddr) );
//
//    assign out = read1 != read2;
//endmodule

static inline void Ndr_ModuleTestMemory()
{
    // map name IDs into char strings
    char * ppNames[20] = {  NULL, 
                           "clk", "raddr", "waddr", "data", "mem_init", "out",  // 1, 2, 3, 4, 5, 6
                           "read1",  "read2",                                   // 7. 8
                           "mem_fo1", "mem_fo2", "mem_fi1", "mem_fi2",          // 9, 10, 11, 12
                           "i_reg1", "i_reg2",                                  // 13, 14
                           "i_read1", "i_read2",                                // 15, 16
                           "i_write1", "i_write2", "memtest"                    // 17, 18, 19
                         };
    // inputs
    int NameIdClk     = 1;
    int NameIdRaddr   = 2;
    int NameIdWaddr   = 3;
    int NameIdData    = 4;
    int NameIdMemInit = 5;
    // flops
    int NameIdFF1     =  9;
    int NameIdFF2     = 10;
    int FaninsFF1[2]  = { 11, 5 };
    int FaninsFF2[2]  = { 12, 5 };
    // writes
    int NameIdWrite1    = 11;
    int NameIdWrite2    = 12;
    int FaninsWrite1[3] = {  9, 3, 4 };
    int FaninsWrite2[3] = { 10, 3, 4 };
    // reads
    int NameIdRead1    =  7;
    int NameIdRead2    =  8;
    int FaninsRead1[2] = { 11, 2 };
    int FaninsRead2[2] = { 12, 2 };
    // compare
    int NameIdComp      = 6;
    int FaninsComp[2]   = { 7, 8 };

    // create a new module 
    void * pDesign = Ndr_Create( 19 );           // create design named "memtest"

    int ModuleID = Ndr_AddModule( pDesign, 19 ); // create module named "memtest"

    // add objects to the module
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,           0,     0, 0, 0,   0, NULL,         1, &NameIdClk,     NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,           0,     8, 0, 0,   0, NULL,         1, &NameIdRaddr,   NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,           0,     8, 0, 0,   0, NULL,         1, &NameIdWaddr,   NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,           0,    31, 0, 0,   0, NULL,         1, &NameIdData,    NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,           0, 16383, 0, 0,   0, NULL,         1, &NameIdMemInit, NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,           0,     0, 0, 0,   1, &NameIdComp,  0, NULL,           NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_DFF,         13, 16383, 0, 0,   2, FaninsFF1,    1, &NameIdFF1,     NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_DFF,         14, 16383, 0, 0,   2, FaninsFF2,    1, &NameIdFF2,     NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_RAMW,        17, 16383, 0, 0,   3, FaninsWrite1, 1, &NameIdWrite1,  NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_RAMW,        18, 16383, 0, 0,   3, FaninsWrite2, 1, &NameIdWrite2,  NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_RAMR,        15,    31, 0, 0,   2, FaninsRead1,  1, &NameIdRead1,   NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_RAMR,        16,    31, 0, 0,   2, FaninsRead2,  1, &NameIdRead2,   NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_COMP_NOTEQU,  0,     0, 0, 0,   2, FaninsComp,   1, &NameIdComp,    NULL );

    // write Verilog for verification
    Ndr_WriteVerilog( NULL, pDesign, ppNames, 0 );
    Ndr_Write( "memtest.ndr", pDesign );
    Ndr_Delete( pDesign );
}

// This testing procedure creates and writes into a Verilog file 
// the following design composed of one word-level flop

// module flop ( input [3:0] data, input clk, input reset, input set, input enable, input async, input sre, input [3:0] init, output [3:0] q );
//   ABC_DFFRSE reg1 ( .d(data), .clk(clk), .reset(reset), .set(set), .enable(enable), .async(async), .sre(sre), .init(init), .q(q) ) ;
// endmodule

static inline void Ndr_ModuleTestFlop()
{
    // map name IDs into char strings
    char * ppNames[12] = { NULL, "flop", "data", "clk", "reset", "set", "enable", "async", "sre", "init", "q" };
    // name IDs
    int NameIdData   =  2;
    int NameIdClk    =  3;
    int NameIdReset  =  4;
    int NameIdSet    =  5;
    int NameIdEnable =  6;
    int NameIdAsync  =  7;
    int NameIdSre    =  8;
    int NameIdInit   =  9;
    int NameIdQ      = 10;
    // array of fanins of node s
    int Fanins[8] = { NameIdData, NameIdClk, NameIdReset, NameIdSet, NameIdEnable, NameIdAsync, NameIdSre, NameIdInit };

    // create a new module
    void * pDesign = Ndr_Create( 1 );

    int ModuleID = Ndr_AddModule( pDesign, 1 );

    // add objects to the modele
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   3, 0, 0,   0, NULL,      1, &NameIdData,   NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   0, 0, 0,   0, NULL,      1, &NameIdClk,    NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   0, 0, 0,   0, NULL,      1, &NameIdReset,  NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   0, 0, 0,   0, NULL,      1, &NameIdSet,    NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   0, 0, 0,   0, NULL,      1, &NameIdEnable, NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   0, 0, 0,   0, NULL,      1, &NameIdAsync,  NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   0, 0, 0,   0, NULL,      1, &NameIdSre,    NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   3, 0, 0,   0, NULL,      1, &NameIdInit,   NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_DFFRSE,   0,   3, 0, 0,   8, Fanins,    1, &NameIdQ,      NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,       0,   3, 0, 0,   1, &NameIdQ,  0, NULL,          NULL );

    // write Verilog for verification
    Ndr_WriteVerilog( NULL, pDesign, ppNames, 0 );
    Ndr_Write( "flop.ndr", pDesign );
    Ndr_Delete( pDesign );
}


// This testing procedure creates and writes into a Verilog file 
// the following design composed of one selector

// module sel ( input [3:0] c, input [2:0] d0, input [2:0] d1, input [2:0] d2, input [2:0] d3, input [2:0] out );
//     wire [2:0] s7 ;
//     always @( c or d0 or d1 or d2 or d3 )
//       begin
//         case ( c )
//           4'b0001 : s7 = d0 ;
//           4'b0010 : s7 = d1 ;
//           4'b0100 : s7 = d2 ;
//           4'b1000 : s7 = d3 ;
//         endcase
//       end
//     assign  out = s7 ;
// endmodule

static inline void Ndr_ModuleTestSelSel()
{
    // map name IDs into char strings
    //char * ppNames[12] = { NULL, "sel", "c", "d0", "d1", "d2", "d3", "out" };
    // name IDs
    int NameIdC      =  2;
    int NameIdD0     =  3;
    int NameIdD1     =  4;
    int NameIdD2     =  5;
    int NameIdD3     =  6;
    int NameIdOut    =  7;
    // array of fanins of node s
    int Fanins[8] = { NameIdC, NameIdD0, NameIdD1, NameIdD2, NameIdD3 };

    // create a new module
    void * pDesign = Ndr_Create( 1 );

    int ModuleID = Ndr_AddModule( pDesign, 1 );

    // add objects to the modele
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   3, 0, 0,   0, NULL,      1, &NameIdC,      NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   2, 0, 0,   0, NULL,      1, &NameIdD0,     NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   2, 0, 0,   0, NULL,      1, &NameIdD1,     NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   2, 0, 0,   0, NULL,      1, &NameIdD2,     NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   2, 0, 0,   0, NULL,      1, &NameIdD3,     NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SEL_SEL,  0,   2, 0, 0,   5, Fanins,    1, &NameIdOut,    NULL );

    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,       0,   2, 0, 0,   1, &NameIdOut,0, NULL,          NULL );

    // write Verilog for verification
    //Ndr_WriteVerilog( NULL, pDesign, ppNames, 0 );
    Ndr_Write( "sel.ndr", pDesign );
    Ndr_Delete( pDesign );
}

// This testing procedure creates and writes into a Verilog file 
// the following design composed of one decoder

// module dec ( input [1:0] in, output [3:0] out );
//     wire out0 = ~in[1] & ~in[0] ;
//     wire out1 = ~in[1] &  in[0] ;
//     wire out2 =  in[1] & ~in[0] ;
//     wire out3 =  in[1] &  in[0] ;
//     assign out = { out3, out2, out1, out0 } ;
// endmodule

static inline void Ndr_ModuleTestDec()
{
    // map name IDs into char strings
    //char * ppNames[12] = { NULL, "dec", "in", "out" };
    // name IDs
    int NameIdIn     =  2;
    int NameIdOut    =  3;

    // create a new module
    void * pDesign = Ndr_Create( 1 );

    int ModuleID = Ndr_AddModule( pDesign, 1 );

    // add objects to the modele
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   1, 0, 0,   0, NULL,       1, &NameIdIn,     NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_SEL_DEC,  0,   3, 0, 0,   1, &NameIdIn,  1, &NameIdOut,    NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,       0,   3, 0, 0,   1, &NameIdOut, 0, NULL,          NULL );

    Ndr_Write( "dec.ndr", pDesign );
    Ndr_Delete( pDesign );
}

// This testing procedure creates and writes into a Verilog file 
// the following design composed of one adder/subtractor

// module addsub ( input mode, input cin, input [2:0] a, input [2:0] b, output [3:0] out );
//     assign out = mode ? a+b+cin : a-b-cin ;
// endmodule

static inline void Ndr_ModuleTestAddSub()
{
    // map name IDs into char strings
    //char * ppNames[12] = { NULL, "addsub", "mode", "cin", "a", "b", "out" };
    // name IDs
    int NameIdInMode =  2;
    int NameIdInCin  =  3;
    int NameIdInA    =  4;
    int NameIdInB    =  5;
    int NameIdOut    =  6;
    int Fanins[8] = { 2, 3, 4, 5 };

    // create a new module
    void * pDesign = Ndr_Create( 1 );

    int ModuleID = Ndr_AddModule( pDesign, 1 );

    // add objects to the modele
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,          0,   0, 0, 0,   0, NULL,       1, &NameIdInMode, NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,          0,   0, 0, 0,   0, NULL,       1, &NameIdInCin,  NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,          0,   2, 0, 0,   0, NULL,       1, &NameIdInA,    NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,          0,   2, 0, 0,   0, NULL,       1, &NameIdInB,    NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_ARI_ADDSUB,  0,   3, 0, 0,   4, Fanins,     1, &NameIdOut,    NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,          0,   3, 0, 0,   1, &NameIdOut, 0, NULL,          NULL );

    Ndr_Write( "addsub.ndr", pDesign );
    Ndr_Delete( pDesign );
}

// This testing procedure creates and writes into a Verilog file 
// the following design composed of one lookup table with function of AND2

// module lut_test ( input [1:0] in, output out );
//     assign out = LUT #(TT=4'h8) lut_inst { in[0], in[1], out } ;
// endmodule

static inline void Ndr_ModuleTestLut()
{
    // map name IDs into char strings
    //char * ppNames[12] = { NULL, "lut_test", "in", "out" };
    // name IDs
    int NameIdIn     =  2;
    int NameIdOut    =  3;

    // create a new module
    void * pDesign = Ndr_Create( 1 );

    int ModuleID = Ndr_AddModule( pDesign, 1 );

    // add objects to the modele
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CI,       0,   1, 0, 0,   0, NULL,       1, &NameIdIn,     NULL );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_LUT,      0,   0, 0, 0,   1, &NameIdIn,  1, &NameIdOut,    (char *)(ABC_CONST(0x8)) );
    Ndr_AddObject( pDesign, ModuleID, ABC_OPER_CO,       0,   0, 0, 0,   1, &NameIdOut, 0, NULL,          NULL );

    Ndr_Write( "lut_test.ndr", pDesign );
    Ndr_Delete( pDesign );
}

ABC_NAMESPACE_HEADER_END

#endif

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