sysc/datatypes/misc/sc_concatref.h

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  source code Copyright (c) 1996-2014 by all Contributors.
  All Rights reserved.

  The contents of this file are subject to the restrictions and limitations
  set forth in the SystemC Open Source License (the "License");
  You may not use this file except in compliance with such restrictions and
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/*****************************************************************************

  sc_concatref.h -- Concatenation support.
 
  Original Author: Andy Goodrich, Forte Design, Inc.
  
 *****************************************************************************/

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

  MODIFICATION LOG - modifiers, enter your name, affiliation, date and
  changes you are making here.

      Name, Affiliation, Date:
  Description of Modification:

  Andy Goodrich, Forte Design Systems, 17 Nov 2002
  Creation of sc_concatref class by merging the capabilities of 
  sc_int_concref, sc_int_concref, sc_uint_concref, sc_uint_concref, 
  and implementing the capabilities of sc_signed_concref, sc_signed_concref, 
  sc_unsigned_concref, and sc_unsigned_concref. The resultant class allows 
  mixed mode concatenations on the left and right sides of an assignment.

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

// $Log: sc_concatref.h,v $
// Revision 1.6  2011/08/24 22:05:48  acg
//  Torsten Maehne: initialization changes to remove warnings.
//
// Revision 1.5  2009/11/17 19:58:15  acg
//  Andy Goodrich: fix of shift rhs possibilities to include "int".
//
// Revision 1.4  2009/02/28 00:26:29  acg
//  Andy Goodrich: bug fixes.
//
// Revision 1.3  2008/04/29 20:23:55  acg
//  Andy Goodrich: fixed the code that assigns the value of a string to
//  an sc_concatref instance.
//
// Revision 1.2  2008/02/14 20:57:26  acg
//  Andy Goodrich: added casts to ~0 instances to keep MSVC compiler happy.
//
// Revision 1.1.1.1  2006/12/15 20:20:05  acg
// SystemC 2.3
//
// Revision 1.4  2006/10/23 19:36:59  acg
//  Andy Goodrich: changed casts for operations on concatenation values to
//  mirror those of sc_unsigned. For instance, an sc_unsigned minus a value
//  returns an sc_signed result, whereas an sc_concatref minus a value was
//  returning an sc_unsigned result. Now both sc_unsigned and sc_concatref
//  minus a value return an sc_signed result.
//
// Revision 1.3  2006/01/13 18:54:01  acg
// Andy Goodrich: added $Log command so that CVS comments are reproduced in
// the source.
//

#ifndef SC_CONCATREF_H
#define SC_CONCATREF_H

#include "sysc/kernel/sc_object.h"
#include "sysc/datatypes/misc/sc_value_base.h"
#include "sysc/utils/sc_temporary.h"
#include "sysc/datatypes/bit/sc_bv.h"
#include "sysc/datatypes/bit/sc_lv.h"
#include "sysc/datatypes/int/sc_int_base.h"
#include "sysc/datatypes/int/sc_uint_base.h"
#include "sysc/datatypes/int/sc_signed.h"
#include "sysc/datatypes/int/sc_unsigned.h"

namespace sc_core {
    extern sc_byte_heap sc_temp_heap; // Temporary storage.
} // namespace sc_core

namespace sc_dt
{

// ----------------------------------------------------------------------------
//  CLASS TEMPLATE : sc_concatref
//
//  Proxy class for sized bit concatenation.
// ----------------------------------------------------------------------------

class sc_concatref : public sc_generic_base<sc_concatref>, public sc_value_base
{
public:
    friend class sc_core::sc_vpool<sc_concatref>;

    inline void initialize( 
        sc_value_base& left, sc_value_base& right )
        {    
            bool left_xz;   // True if x's and/or z's found in left.
            bool right_xz;  // True if x's and/or z's found in right.
            
            m_left_p = (sc_value_base*)&left;
            m_right_p = (sc_value_base*)&right;
            m_len_r = right.concat_length(&right_xz);
            m_len = left.concat_length(&left_xz) + m_len_r;
            m_flags = ( left_xz || right_xz ) ? cf_xz_present : cf_none;
        }


    inline void initialize( 
        const sc_value_base& left, const sc_value_base& right )
        {    
            bool left_xz;   // True if x's and/or z's found in left.
            bool right_xz;  // True if x's and/or z's found in right.

            m_left_p = (sc_value_base*)&left;
            m_right_p = (sc_value_base*)&right;
            m_len_r = right.concat_length(&right_xz);
            m_len = left.concat_length(&left_xz) + m_len_r;
            m_flags = ( left_xz || right_xz ) ? cf_xz_present : cf_none;
        }

    // destructor

    virtual ~sc_concatref()
    {}


    // capacity

    unsigned int length() const
        { return m_len; }

#ifdef SC_DT_DEPRECATED
    int bitwidth() const
        { return length(); }
#endif

    // concatenation

    virtual int concat_length( bool* xz_present_p ) const
    { 
        if ( xz_present_p ) 
            *xz_present_p = m_flags & cf_xz_present ? true : false;
        return m_len; 
    }

    virtual void concat_clear_data( bool to_ones )
    { 
        m_left_p->concat_clear_data(to_ones); 
        m_right_p->concat_clear_data(to_ones); 
    }

    virtual bool concat_get_ctrl( sc_digit* dst_p, int low_i ) const
    {
        bool rnz = m_right_p->concat_get_ctrl( dst_p, low_i );
        bool lnz = m_left_p->concat_get_ctrl( dst_p, low_i+m_len_r );
        return rnz || lnz;
    }

    virtual bool concat_get_data( sc_digit* dst_p, int low_i ) const
    {
        bool rnz = m_right_p->concat_get_data( dst_p, low_i );
        bool lnz = m_left_p->concat_get_data( dst_p, low_i+m_len_r );
        return rnz || lnz;
    }

    virtual uint64 concat_get_uint64() const
    {
        if ( m_len_r >= 64 )
            return m_right_p->concat_get_uint64();
        else
        {
            return (m_left_p->concat_get_uint64() << m_len_r) | 
                m_right_p->concat_get_uint64();
        }
    }

    virtual void concat_set( int64 src, int low_i ) 
    { 
        m_right_p->concat_set( src, low_i );
        m_left_p->concat_set( src, low_i+m_len_r);
    }

    virtual void concat_set( const sc_signed& src, int low_i ) 
    {
        m_right_p->concat_set( src, low_i );
        m_left_p->concat_set( src, low_i+m_len_r);
    }

    virtual void concat_set( const sc_unsigned& src, int low_i ) 
    { 
        m_right_p->concat_set( src, low_i );
        m_left_p->concat_set( src, low_i+m_len_r);
    }

    virtual void concat_set( uint64 src, int low_i )
    { 
        m_right_p->concat_set( src, low_i );
        m_left_p->concat_set( src, low_i+m_len_r);
    }


    // explicit conversions

    uint64 to_uint64() const 
        {
            uint64 mask;
            uint64 result;

            result = m_right_p->concat_get_uint64();
            if ( m_len_r < 64 )
            {
                mask = (uint64)~0;
                result = (m_left_p->concat_get_uint64() << m_len_r) | 
                            (result & ~(mask << m_len_r));
            }
            if ( m_len < 64 )
            {
                mask = (uint64)~0;
                result = result & ~(mask << m_len);
            }
            return result;
        }

    const sc_unsigned& value() const
        {
            bool           left_non_zero;
            sc_unsigned*   result_p = sc_unsigned::m_pool.allocate();
            bool           right_non_zero;

            result_p->nbits = result_p->num_bits(m_len);
            result_p->ndigits = DIV_CEIL(result_p->nbits);
            result_p->digit = (sc_digit*)sc_core::sc_temp_heap.allocate( 
                sizeof(sc_digit)*result_p->ndigits );
#if defined(_MSC_VER)
            // workaround spurious initialisation issue on MS Visual C++
            memset( result_p->digit, 0, sizeof(sc_digit)*result_p->ndigits );
#else
            result_p->digit[result_p->ndigits-1] = 0;
#endif
            right_non_zero = m_right_p->concat_get_data( result_p->digit, 0 );
            left_non_zero = m_left_p->concat_get_data(result_p->digit, m_len_r); 
            if ( left_non_zero || right_non_zero ) 
                result_p->sgn = SC_POS;
            else
                result_p->sgn = SC_ZERO;
            return *result_p;
        }

    int64 to_int64() const
        { 
            return (int64)to_uint64();
        }
    int to_int() const
        { return (int)to_int64(); }
    unsigned int  to_uint() const
        { return (unsigned int)to_uint64(); }
    long to_long() const
        { return (long)to_int64(); }
    unsigned long to_ulong() const
        { return (unsigned long)to_uint64(); }
    double to_double() const
        { return value().to_double(); }

    void to_sc_signed( sc_signed& target ) const
        { target = value(); }

    void to_sc_unsigned( sc_unsigned& target ) const
        { target = value(); }

    // implicit conversions:

    operator  uint64 () const 
        { return to_uint64(); }

    operator const sc_unsigned& () const
        { return value(); }

    // unary operators:

    sc_unsigned operator + () const
        { return value(); } 

    sc_signed operator - () const
        { return -value(); } 

    sc_unsigned operator ~ () const
        { return ~value(); } 

    // explicit conversion to character string

    const std::string to_string( sc_numrep numrep = SC_DEC ) const
        { return value().to_string(numrep); }

    const std::string to_string( sc_numrep numrep, bool w_prefix ) const
        { return value().to_string(numrep,w_prefix); }



    // assignments

    inline const sc_concatref& operator = ( int v )
    {
        m_right_p->concat_set((int64)v, 0);
        m_left_p->concat_set((int64)v, m_len_r);
        return *this;
    }

    inline const sc_concatref& operator = ( long v )
    {
        m_right_p->concat_set((int64)v, 0);
        m_left_p->concat_set((int64)v, m_len_r);
        return *this;
    }

    inline const sc_concatref& operator = ( int64 v )
    {
        m_right_p->concat_set(v, 0);
        m_left_p->concat_set(v, m_len_r);
        return *this;
    }

    inline const sc_concatref& operator = ( unsigned int v )
    {
        m_right_p->concat_set((uint64)v, 0);
        m_left_p->concat_set((uint64)v, m_len_r);
        return *this;
    }

    inline const sc_concatref& operator = ( unsigned long v )
    {
        m_right_p->concat_set((uint64)v, 0);
        m_left_p->concat_set((uint64)v, m_len_r);
        return *this;
    }

    inline const sc_concatref& operator = ( uint64 v )
    {
        m_right_p->concat_set(v, 0);
        m_left_p->concat_set(v, m_len_r);
        return *this;
    }

    const sc_concatref& operator = ( const sc_concatref& v )
    {
        sc_unsigned temp(v.length());
        temp = v.value();
        m_right_p->concat_set(temp, 0);
        m_left_p->concat_set(temp, m_len_r);
        return *this;
    }

    const sc_concatref& operator = ( const sc_signed& v )
    {
        m_right_p->concat_set(v, 0);
        m_left_p->concat_set(v, m_len_r);
        return *this;
    }

    const sc_concatref& operator = ( const sc_unsigned& v )
    {
        m_right_p->concat_set(v, 0);
        m_left_p->concat_set(v, m_len_r);
        return *this;
    }

    const sc_concatref& operator = ( const char* v_p )
    {
        sc_unsigned v(m_len);
        v = v_p;
        m_right_p->concat_set(v, 0);
        m_left_p->concat_set(v, m_len_r);
        return *this;
    }

    const sc_concatref& operator = ( const sc_bv_base& v )
    {
        sc_unsigned temp(v.length());
        temp = v;
        m_right_p->concat_set(temp, 0);
        m_left_p->concat_set(temp, m_len_r);
        return *this;
    }

    const sc_concatref& operator = ( const sc_lv_base& v )
    {
        sc_unsigned data(v.length());
        data = v;
        m_right_p->concat_set(data, 0);
        m_left_p->concat_set(data, m_len_r);
        return *this;
    }


    // reduce methods

    bool and_reduce() const
        { return value().and_reduce(); }

    bool nand_reduce() const
        { return value().nand_reduce(); }

    bool or_reduce() const
        { return value().or_reduce(); }

    bool nor_reduce() const
        { return value().nor_reduce(); }

    bool xor_reduce() const
        { return value().xor_reduce(); }

    bool xnor_reduce() const
        { return value().xnor_reduce(); }

    // other methods

    void print( ::std::ostream& os = ::std::cout ) const
        { os << this->value(); }

    void scan( ::std::istream& is ) 
    { 
        std::string s; 
        is >> s; 
        *this = s.c_str(); 
    } 

public:
    static sc_core::sc_vpool<sc_concatref> m_pool; // Pool of temporary objects.

public:
    enum concat_flags {
        cf_none = 0,        // Normal value. 
        cf_xz_present = 1   // X and/or Z values present.
    };

protected:
    sc_value_base*  m_left_p;    // Left hand operand of concatenation.
    sc_value_base*  m_right_p;   // Right hand operand of concatenation.
    int             m_len;       // Length of concatenation.
    int             m_len_r;     // Length of m_rightt_p.
    concat_flags    m_flags;     // Value is read only.

private:
    sc_concatref(const sc_concatref&);
    sc_concatref() : m_left_p(0), m_right_p(0), m_len(0), m_len_r(0), m_flags()
      {}
};


// functional notation for the reduce methods

inline
bool
and_reduce( const sc_concatref& a )
{
    return a.and_reduce();
}

inline
bool
nand_reduce( const sc_concatref& a )
{
    return a.nand_reduce();
}

inline
bool
or_reduce( const sc_concatref& a )
{
    return a.or_reduce();
}

inline
bool
nor_reduce( const sc_concatref& a )
{
    return a.nor_reduce();
}

inline
bool
xor_reduce( const sc_concatref& a )
{
    return a.xor_reduce();
}

inline
bool
xnor_reduce( const sc_concatref& a )
{
    return a.xnor_reduce();
}


// SHIFT OPERATORS FOR sc_concatref OBJECT INSTANCES:
//
// Because sc_concatref has implicit casts to both uint64 and sc_unsigned
// it is necessary to disambiguate the use of the shift operators. We do
// this in favor of sc_unsigned so that precision is not lost. To get an
// integer-based result use a cast to uint64 before performing the shift.

inline const sc_unsigned operator << (const sc_concatref& target, uint64 shift)
{
    return target.value() << (int)shift;
}

inline const sc_unsigned operator << (const sc_concatref& target, int64 shift)
{
    return target.value() << (int)shift;
}

inline const sc_unsigned operator << ( 
    const sc_concatref& target, unsigned long shift )
{
    return target.value() << (int)shift;
}

inline const sc_unsigned operator << ( 
    const sc_concatref& target, int shift )
{
    return target.value() << shift;
}

inline const sc_unsigned operator << ( 
    const sc_concatref& target, unsigned int shift )
{
    return target.value() << (int)shift;
}

inline const sc_unsigned operator << ( const sc_concatref& target, long shift )
{
    return target.value() << (int)shift;
}

inline const sc_unsigned operator >> (const sc_concatref& target, uint64 shift)
{
    return target.value() >> (int)shift;
}

inline const sc_unsigned operator >> (const sc_concatref& target, int64 shift)
{
    return target.value() >> (int)shift;
}

inline const sc_unsigned operator >> ( 
    const sc_concatref& target, unsigned long shift )
{
    return target.value() >> (int)shift;
}

inline const sc_unsigned operator >> ( 
    const sc_concatref& target, int shift )
{
    return target.value() >> shift;
}

inline const sc_unsigned operator >> ( 
    const sc_concatref& target, unsigned int shift )
{
    return target.value() >> (int)shift;
}

inline const sc_unsigned operator >> ( const sc_concatref& target, long shift )
{
    return target.value() >> (int)shift;
}


// STREAM OPERATORS FOR sc_concatref OBJECT INSTANCES:

inline
::std::ostream&
operator << ( ::std::ostream& os, const sc_concatref& v )
{ 
    return os << v.value();
}

inline
::std::istream&
operator >> ( ::std::istream& is, sc_concatref& a )
{
    sc_unsigned temp(a.concat_length(0));   
    temp.scan( is );
    a = temp;
    return is;
}


// ----------------------------------------------------------------------------
//  CLASS TEMPLATE : sc_concat_bool
//
//  Proxy class for read-only boolean values in concatenations.
// ----------------------------------------------------------------------------

class sc_concat_bool : public sc_value_base
{
  protected:
    static sc_core::sc_vpool<sc_concat_bool> m_pool;  // Temporaries pool.
    bool                                     m_value; // Value for this obj.

  public:

    // constructor:
    
    sc_concat_bool()
    : sc_value_base(), m_value()
    {}

    // destructor:

    virtual ~sc_concat_bool() 
        { }

    // allocation of temporary object:

    static inline sc_concat_bool* allocate( bool v )
    {
        sc_concat_bool* result_p = m_pool.allocate();
        result_p->m_value = v;
        return result_p;
    }

    // concatenation:

    virtual int concat_length( bool* xz_present_p ) const
    { 
        if ( xz_present_p ) *xz_present_p = false;
        return 1; 
    }

    virtual bool concat_get_ctrl( sc_digit* dst_p, int low_i ) const
    {
        int bit = 1 << (low_i % BITS_PER_DIGIT); 
        int word_i = low_i / BITS_PER_DIGIT;
        dst_p[word_i] &= ~bit;
        return false;
    }

    virtual bool concat_get_data( sc_digit* dst_p, int low_i ) const
    {
        int bit = 1 << (low_i % BITS_PER_DIGIT); 
        int word_i = low_i / BITS_PER_DIGIT;
        if ( m_value )
            dst_p[word_i] |= bit;
        else 
            dst_p[word_i] &= ~bit;
        return m_value;
    }

    virtual uint64 concat_get_uint64() const
    {
        return m_value ? 1 : 0;
    }
};


// ----------------------------------------------------------------------------
// ARITHMETIC AND LOGIC OPERATORS FOR sc_concatref
// ----------------------------------------------------------------------------

#define SC_CONCAT_OP_TYPE(RESULT,OP,OTHER_TYPE) \
    inline RESULT operator OP ( const sc_concatref& a, OTHER_TYPE b ) \
    { \
        return a.value() OP b; \
    } \
    inline RESULT operator OP ( OTHER_TYPE a, const sc_concatref& b ) \
    { \
        return a OP b.value(); \
    } 


#define SC_CONCAT_OP(RESULT,OP) \
    inline RESULT operator OP ( const sc_concatref& a, const sc_concatref& b ) \
    { \
        return a.value() OP b.value(); \
    }  \
    SC_CONCAT_OP_TYPE(const sc_signed,OP,int) \
    SC_CONCAT_OP_TYPE(const sc_signed,OP,long) \
    SC_CONCAT_OP_TYPE(const sc_signed,OP,int64) \
    SC_CONCAT_OP_TYPE(RESULT,OP,unsigned int) \
    SC_CONCAT_OP_TYPE(RESULT,OP,unsigned long) \
    SC_CONCAT_OP_TYPE(RESULT,OP,uint64) \
    SC_CONCAT_OP_TYPE(const sc_signed,OP,const sc_int_base&) \
    SC_CONCAT_OP_TYPE(RESULT,OP,const sc_uint_base&) \
    SC_CONCAT_OP_TYPE(const sc_signed,OP,const sc_signed&) \
    SC_CONCAT_OP_TYPE(RESULT,OP,const sc_unsigned&) \
    inline RESULT operator OP ( const sc_concatref& a, bool b ) \
    { \
        return a.value() OP (int)b; \
    } \
    inline RESULT operator OP ( bool a, const sc_concatref& b ) \
    { \
        return (int)a OP b.value(); \
    } 

#define SC_CONCAT_BOOL_OP(OP) \
    inline bool operator OP ( const sc_concatref& a, const sc_concatref& b ) \
    { \
        return a.value() OP b.value(); \
    }  \
    SC_CONCAT_OP_TYPE(bool,OP,int) \
    SC_CONCAT_OP_TYPE(bool,OP,long) \
    SC_CONCAT_OP_TYPE(bool,OP,int64) \
    SC_CONCAT_OP_TYPE(bool,OP,unsigned int) \
    SC_CONCAT_OP_TYPE(bool,OP,unsigned long) \
    SC_CONCAT_OP_TYPE(bool,OP,uint64) \
    SC_CONCAT_OP_TYPE(bool,OP,const sc_int_base&) \
    SC_CONCAT_OP_TYPE(bool,OP,const sc_uint_base&) \
    SC_CONCAT_OP_TYPE(bool,OP,const sc_signed&) \
    SC_CONCAT_OP_TYPE(bool,OP,const sc_unsigned&) \
    inline bool operator OP ( const sc_concatref& a, bool b ) \
    { \
        return a.value() OP (int)b; \
    } \
    inline bool operator OP ( bool a, const sc_concatref& b ) \
    { \
        return (int)a OP b.value(); \
    } 

SC_CONCAT_OP(const sc_unsigned,+)
SC_CONCAT_OP(const sc_signed,-)
SC_CONCAT_OP(const sc_unsigned,*)
SC_CONCAT_OP(const sc_unsigned,/)
SC_CONCAT_OP(const sc_unsigned,%)
SC_CONCAT_OP(const sc_unsigned,&)
SC_CONCAT_OP(const sc_unsigned,|)
SC_CONCAT_OP(const sc_unsigned,^)
SC_CONCAT_BOOL_OP(==)
SC_CONCAT_BOOL_OP(<=)
SC_CONCAT_BOOL_OP(>=)
SC_CONCAT_BOOL_OP(!=)
SC_CONCAT_BOOL_OP(>)
SC_CONCAT_BOOL_OP(<)

#undef SC_CONCAT_OP
#undef SC_CONCAT_OP_TYPE


// ----------------------------------------------------------------------------
// CONCATENATION FUNCTION AND OPERATOR FOR STANDARD SYSTEM C DATA TYPES:
// ----------------------------------------------------------------------------

inline sc_dt::sc_concatref& concat(
    sc_dt::sc_value_base& a, sc_dt::sc_value_base& b)
{
    sc_dt::sc_concatref* result_p;     // Proxy for the concatenation.

    result_p = sc_dt::sc_concatref::m_pool.allocate();
    result_p->initialize( a, b );
    return *result_p;
}

inline 
const
sc_dt::sc_concatref& concat(
    const sc_dt::sc_value_base& a, const sc_dt::sc_value_base& b)
{
    sc_dt::sc_concatref* result_p;     // Proxy for the concatenation.

    result_p = sc_dt::sc_concatref::m_pool.allocate();
    result_p->initialize( a, b );
    return *result_p;
}

inline 
const
sc_dt::sc_concatref& concat(const sc_dt::sc_value_base& a, bool b)
{
    const sc_dt::sc_concat_bool* b_p;        // Proxy for boolean value.
    sc_dt::sc_concatref*         result_p;   // Proxy for the concatenation.

    b_p = sc_dt::sc_concat_bool::allocate(b);
    result_p = sc_dt::sc_concatref::m_pool.allocate();
    result_p->initialize( a, *b_p );
    return *result_p;
}

inline 
const
sc_dt::sc_concatref& concat(bool a, const sc_dt::sc_value_base& b)
{
    const sc_dt::sc_concat_bool* a_p;        // Proxy for boolean value.
    sc_dt::sc_concatref*         result_p;   // Proxy for the concatenation.

    a_p = sc_dt::sc_concat_bool::allocate(a);
    result_p = sc_dt::sc_concatref::m_pool.allocate();
    result_p->initialize( *a_p, b );
    return *result_p;
}

inline sc_dt::sc_concatref& operator , (
    sc_dt::sc_value_base& a, sc_dt::sc_value_base& b)
{
    sc_dt::sc_concatref* result_p;     // Proxy for the concatenation.

    result_p = sc_dt::sc_concatref::m_pool.allocate();
    result_p->initialize( a, b );
    return *result_p;
}

inline 
const
sc_dt::sc_concatref& operator , (
    const sc_dt::sc_value_base& a, const sc_dt::sc_value_base& b)
{
    sc_dt::sc_concatref* result_p;     // Proxy for the concatenation.

    result_p = sc_dt::sc_concatref::m_pool.allocate();
    result_p->initialize( a, b );
    return *result_p;
}

inline 
const
sc_dt::sc_concatref& operator , (const sc_dt::sc_value_base& a, bool b)
{
    const sc_dt::sc_concat_bool* b_p;      // Proxy for boolean value.
    sc_dt::sc_concatref*         result_p; // Proxy for the concatenation.

    b_p = sc_dt::sc_concat_bool::allocate(b);
    result_p = sc_dt::sc_concatref::m_pool.allocate();
    result_p->initialize( a, *b_p );
    return *result_p;
}

inline 
const
sc_dt::sc_concatref& operator , (bool a, const sc_dt::sc_value_base& b)
{
    const sc_dt::sc_concat_bool* a_p;      // Proxy for boolean value.
    sc_dt::sc_concatref*         result_p; // Proxy for the concatenation.

    a_p = sc_dt::sc_concat_bool::allocate(a);
    result_p = sc_dt::sc_concatref::m_pool.allocate();
    result_p->initialize( *a_p, b );
    return *result_p;
}

} // namespace sc_dt

#endif //  SC_CONCATREF_H

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