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

  FileName    [wlcNtk.c]

  SystemName  [ABC: Logic synthesis and verification system.]

  PackageName [Verilog parser.]

  Synopsis    [Network data-structure.]

  Author      [Alan Mishchenko]
  
  Affiliation [UC Berkeley]

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

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

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

#include "wlc.h"
#include "misc/vec/vecWec.h"

ABC_NAMESPACE_IMPL_START


////////////////////////////////////////////////////////////////////////
///                        DECLARATIONS                              ///
////////////////////////////////////////////////////////////////////////

// object types
static char * Wlc_Names[WLC_OBJ_NUMBER+1] = { 
    NULL,                  // 00: unknown
    "pi",                  // 01: primary input 
    "po",                  // 02: primary output 
    "ff",                  // 03: box output
    "bi",                  // 04: box input
    "ff",                  // 05: flop
    "const",               // 06: constant
    "buf",                 // 07: buffer
    "mux",                 // 08: multiplexer
    ">>",                  // 09: shift right
    ">>>",                 // 10: shift right (arithmetic)
    "<<",                  // 11: shift left
    "<<<",                 // 12: shift left (arithmetic)
    "rotateR",             // 13: shift left (arithmetic)
    "rotateL",             // 14: shift left (arithmetic)
    "~",                   // 15: bitwise NOT
    "&",                   // 16: bitwise AND
    "|",                   // 17: bitwise OR
    "^",                   // 18: bitwise XOR
    "[:]",                 // 19: bit selection
    "{,}",                 // 20: bit concatenation
    "zeroPad",             // 21: zero padding
    "signExt",             // 22: sign extension
    "!",                   // 23: logic NOT
    "&&",                  // 24: logic AND
    "||",                  // 25: logic OR
    "==",                  // 26: compare equal
    "!=",                  // 27: compare not equal
    "<",                   // 28: compare less
    ">",                   // 29: compare more
    "<=",                  // 30: compare less or equal
    ">=",                  // 31: compare more or equal
    "&",                   // 32: reduction AND
    "|",                   // 33: reduction OR
    "^",                   // 34: reduction XOR
    "+",                   // 35: arithmetic addition
    "-",                   // 36: arithmetic subtraction
    "*",                   // 37: arithmetic multiplier
    "//",                  // 38: arithmetic division
    "%",                   // 39: arithmetic modulus
    "**",                  // 40: arithmetic power
    "-",                   // 41: arithmetic minus
    "table",               // 42: bit table
    NULL                   // 43: unused
};

////////////////////////////////////////////////////////////////////////
///                     FUNCTION DEFINITIONS                         ///
////////////////////////////////////////////////////////////////////////

/**Function*************************************************************

  Synopsis    [Working with models.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Wlc_Ntk_t * Wlc_NtkAlloc( char * pName, int nObjsAlloc )
{
    Wlc_Ntk_t * p;
    p = ABC_CALLOC( Wlc_Ntk_t, 1 );
    p->pName = Extra_FileNameGeneric( pName );
    Vec_IntGrow( &p->vPis, 111 );
    Vec_IntGrow( &p->vPos, 111 );
    Vec_IntGrow( &p->vCis, 111 );
    Vec_IntGrow( &p->vCos, 111 );
    Vec_IntGrow( &p->vFfs, 111 );
    p->pMemFanin = Mem_FlexStart();
    p->nObjsAlloc = nObjsAlloc;  
    p->pObjs = ABC_CALLOC( Wlc_Obj_t, p->nObjsAlloc );
    p->iObj = 1;
    return p;
}
void Wlc_ObjSetCi( Wlc_Ntk_t * p, Wlc_Obj_t * pObj )
{
    assert( Wlc_ObjIsCi(pObj) );
    assert( Wlc_ObjFaninNum(pObj) == 0 );
    if ( Wlc_NtkPiNum(p) == Wlc_NtkCiNum(p) || pObj->Type != WLC_OBJ_PI )
    {
        pObj->Fanins[1] = Vec_IntSize(&p->vCis);
        Vec_IntPush( &p->vCis, Wlc_ObjId(p, pObj) );
    }
    else // insert in the array of CI at the end of PIs
    {
        Wlc_Obj_t * pTemp; int i;
        Vec_IntInsert( &p->vCis, Wlc_NtkPiNum(p), Wlc_ObjId(p, pObj) );
        // other CI IDs are invalidated... naive fix!
        Wlc_NtkForEachCi( p, pTemp, i )
            pTemp->Fanins[1] = i;
    }
    if ( pObj->Type == WLC_OBJ_PI )
        Vec_IntPush( &p->vPis, Wlc_ObjId(p, pObj) );
}
void Wlc_ObjSetCo( Wlc_Ntk_t * p, Wlc_Obj_t * pObj, int fFlopInput )
{
//    pObj->Fanins[1] = Vec_IntSize(&p->vCos);
    Vec_IntPush( &p->vCos, Wlc_ObjId(p, pObj) );
    if ( !fFlopInput )
        Vec_IntPush( &p->vPos, Wlc_ObjId(p, pObj) );
    if ( fFlopInput )
        pObj->fIsFi = 1;
    else
        pObj->fIsPo = 1;
}
int Wlc_ObjAlloc( Wlc_Ntk_t * p, int Type, int Signed, int End, int Beg )
{
    Wlc_Obj_t * pObj;
    assert( Type != WLC_OBJ_PO && Type != WLC_OBJ_FI );
    if ( p->iObj == p->nObjsAlloc )
    {
        p->pObjs = ABC_REALLOC( Wlc_Obj_t, p->pObjs, 2 * p->nObjsAlloc );
        memset( p->pObjs + p->nObjsAlloc, 0, sizeof(Wlc_Obj_t) * p->nObjsAlloc );
        p->nObjsAlloc *= 2;
    }
    pObj = Wlc_NtkObj( p, p->iObj );
    pObj->Type   = Type;
    pObj->Signed = Signed;
    pObj->End    = End;
    pObj->Beg    = Beg;
    if ( Wlc_ObjIsCi(pObj) )
        Wlc_ObjSetCi( p, pObj );
    p->nObjs[Type]++;
    return p->iObj++;
}
int Wlc_ObjCreate( Wlc_Ntk_t * p, int Type, int Signed, int End, int Beg, Vec_Int_t * vFanins )
{
    int iFaninNew = Wlc_ObjAlloc( p, Type, Signed, End, Beg );
    Wlc_ObjAddFanins( p, Wlc_NtkObj(p, iFaninNew), vFanins );
    return iFaninNew;
}
char * Wlc_ObjName( Wlc_Ntk_t * p, int iObj )
{
    static char Buffer[100];
    if ( Wlc_NtkHasNameId(p) && Wlc_ObjNameId(p, iObj) )
        return Abc_NamStr( p->pManName, Wlc_ObjNameId(p, iObj) );
    sprintf( Buffer, "n%d", iObj );
    return Buffer;
}                          
void Wlc_ObjUpdateType( Wlc_Ntk_t * p, Wlc_Obj_t * pObj, int Type )
{
    assert( pObj->Type == WLC_OBJ_NONE );
    p->nObjs[pObj->Type]--;
    pObj->Type = Type;
    p->nObjs[pObj->Type]++;
}
void Wlc_ObjAddFanins( Wlc_Ntk_t * p, Wlc_Obj_t * pObj, Vec_Int_t * vFanins )
{
    assert( pObj->nFanins == 0 );
    pObj->nFanins = Vec_IntSize(vFanins);
    if ( Wlc_ObjHasArray(pObj) )
        pObj->pFanins[0] = (int *)Mem_FlexEntryFetch( p->pMemFanin, Vec_IntSize(vFanins) * sizeof(int) );
    memcpy( Wlc_ObjFanins(pObj), Vec_IntArray(vFanins), sizeof(int) * Vec_IntSize(vFanins) );
    // special treatment of CONST, SELECT and TABLE
    if ( pObj->Type == WLC_OBJ_CONST )
        pObj->nFanins = 0;
    else if ( pObj->Type == WLC_OBJ_BIT_SELECT || pObj->Type == WLC_OBJ_TABLE )
        pObj->nFanins = 1;
}
void Wlc_NtkFree( Wlc_Ntk_t * p )
{
    if ( p->pManName )
        Abc_NamStop( p->pManName );
    if ( p->pMemFanin )
        Mem_FlexStop( p->pMemFanin, 0 );
    if ( p->pMemTable )
        Mem_FlexStop( p->pMemTable, 0 );
    Vec_PtrFreeP( &p->vTables );
    ABC_FREE( p->vPis.pArray );
    ABC_FREE( p->vPos.pArray );
    ABC_FREE( p->vCis.pArray );
    ABC_FREE( p->vCos.pArray );
    ABC_FREE( p->vFfs.pArray );
    Vec_IntFreeP( &p->vInits );
    ABC_FREE( p->vTravIds.pArray );
    ABC_FREE( p->vNameIds.pArray );
    ABC_FREE( p->vCopies.pArray );
    ABC_FREE( p->pInits );
    ABC_FREE( p->pObjs );
    ABC_FREE( p->pName );
    ABC_FREE( p );
}
int Wlc_NtkMemUsage( Wlc_Ntk_t * p )
{
    int Mem = sizeof(Wlc_Ntk_t);
    Mem += 4 * p->vPis.nCap;
    Mem += 4 * p->vPos.nCap;
    Mem += 4 * p->vCis.nCap;
    Mem += 4 * p->vCos.nCap;
    Mem += 4 * p->vFfs.nCap;
    Mem += sizeof(Wlc_Obj_t) * p->nObjsAlloc;
    Mem += Abc_NamMemUsed(p->pManName);
    Mem += Mem_FlexReadMemUsage(p->pMemFanin);
    return Mem;
}

/**Function*************************************************************

  Synopsis    [Prints distribution of operator types.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
static inline void Vec_WrdSelectSortCost2( word * pArray, int nSize, word * pCosts )
{
    int i, j, best_i;
    for ( i = 0; i < nSize-1; i++ )
    {
        best_i = i;
        for ( j = i+1; j < nSize; j++ )
            if ( pCosts[j] < pCosts[best_i] )
                best_i = j;
        ABC_SWAP( word, pArray[i], pArray[best_i] );
        ABC_SWAP( word, pCosts[i], pCosts[best_i] );
    }
}
static inline word Wlc_NtkPrintDistribMakeSign( int s, int s0, int s1 )
{
    return ((word)s1 << 42) | ((word)s0 << 21) | (word)s;
}
static inline void Wlc_NtkPrintDistribFromSign( word sss, int * s, int * s0, int * s1 )
{
    *s1 =  (int)(sss >> 42);  *s0 = (int)(sss >> 21) & 0x1FFFFF;  *s  =  (int)sss & 0x1FFFFF;
}
static inline void Wlc_NtkPrintDistribAddOne( Vec_Ptr_t * vTypes, Vec_Ptr_t * vOccurs, int Type, word Sign )
{
    Vec_Wrd_t * vType  = (Vec_Wrd_t *)Vec_PtrEntry( vTypes, Type );
    Vec_Wrd_t * vOccur = (Vec_Wrd_t *)Vec_PtrEntry( vOccurs, Type );
    word Entry; int i;
    Vec_WrdForEachEntry( vType, Entry, i )
        if ( Entry == Sign )
        {
            Vec_WrdAddToEntry( vOccur, i, 1 );
            return;
        }
    Vec_WrdPush( vType, Sign );
    Vec_WrdPush( vOccur, 1 );
}
void Wlc_NtkPrintDistribSortOne( Vec_Ptr_t * vTypes, Vec_Ptr_t * vOccurs, int Type )
{
    Vec_Wrd_t * vType  = (Vec_Wrd_t *)Vec_PtrEntry( vTypes, Type );
    Vec_Wrd_t * vOccur = (Vec_Wrd_t *)Vec_PtrEntry( vOccurs, Type );
    Vec_WrdSelectSortCost2( Vec_WrdArray(vType), Vec_WrdSize(vType), Vec_WrdArray(vOccur) );
    Vec_WrdReverseOrder( vType );
    Vec_WrdReverseOrder( vOccur );
}
void Wlc_NtkPrintDistrib( Wlc_Ntk_t * p, int fVerbose )
{
    Wlc_Obj_t * pObj; 
    Vec_Ptr_t * vTypes, * vOccurs;
    word Sign;
    int i, k, s, s0, s1;
    // allocate statistics arrays
    vTypes  = Vec_PtrStart( WLC_OBJ_NUMBER );
    vOccurs = Vec_PtrStart( WLC_OBJ_NUMBER );
    for ( i = 0; i < WLC_OBJ_NUMBER; i++ )
        Vec_PtrWriteEntry( vTypes, i, Vec_WrdAlloc(16) );
    for ( i = 0; i < WLC_OBJ_NUMBER; i++ )
        Vec_PtrWriteEntry( vOccurs, i, Vec_WrdAlloc(16) );
    // add nodes
    Wlc_NtkForEachObj( p, pObj, i )
    {
//        char * pName = Wlc_ObjName(p, i);
        if ( Wlc_ObjSign(pObj) > 0x1FFFFF )
            printf( "Object %6d has range %d, which is reduced to %d in the statistics.\n", 
                i, Wlc_ObjRange(pObj), Wlc_ObjRange(pObj) & 0xFFFFF );
        if ( pObj->Beg )
            printf( "Object %6d has non-standard range %d=[%d:%d]\n", i, Wlc_ObjRange(pObj), pObj->End, pObj->Beg );
       // 0-input types
        if ( Wlc_ObjIsCi(pObj) || pObj->Type == WLC_OBJ_CONST || pObj->Type == WLC_OBJ_BIT_CONCAT )
            Sign = Wlc_NtkPrintDistribMakeSign( Wlc_ObjSign(pObj), 0, 0 );
        // 1-input types
        else if ( pObj->Type == WLC_OBJ_BUF    || pObj->Type == WLC_OBJ_BIT_SELECT  || pObj->Type == WLC_OBJ_TABLE ||
             pObj->Type == WLC_OBJ_BIT_ZEROPAD || pObj->Type == WLC_OBJ_BIT_SIGNEXT || 
             pObj->Type == WLC_OBJ_BIT_NOT     || pObj->Type == WLC_OBJ_LOGIC_NOT   || pObj->Type == WLC_OBJ_ARI_MINUS )
            Sign = Wlc_NtkPrintDistribMakeSign( Wlc_ObjSign(pObj), Wlc_ObjSign(Wlc_ObjFanin0(p, pObj)), 0 );
        // 2-input types (including MUX)
        else if ( Wlc_ObjFaninNum(pObj) == 1 )
            Sign = Wlc_NtkPrintDistribMakeSign( Wlc_ObjSign(pObj), Wlc_ObjSign(Wlc_ObjFanin0(p, pObj)), 0 );
        else
        {
            assert( Wlc_ObjFaninNum(pObj) >= 2 );
            Sign = Wlc_NtkPrintDistribMakeSign( Wlc_ObjSign(pObj), Wlc_ObjSign(Wlc_ObjFanin0(p, pObj)), Wlc_ObjSign(Wlc_ObjFanin1(p, pObj)) );
        }
        // add to storage
        Wlc_NtkPrintDistribAddOne( vTypes, vOccurs, pObj->Type, Sign );
    }
    // print by occurrence
    printf( "ID  :  name  occurrence (occurrence)<output_range>=<input_range>.<input_range> ...\n" );
    for ( i = 0; i < WLC_OBJ_NUMBER; i++ )
    {
        Vec_Wrd_t * vType  = (Vec_Wrd_t *)Vec_PtrEntry( vTypes, i );
        Vec_Wrd_t * vOccur = (Vec_Wrd_t *)Vec_PtrEntry( vOccurs, i );
        if ( p->nObjs[i] == 0 )
            continue;
        printf( "%2d  :  %-8s  %6d ", i, Wlc_Names[i], p->nObjs[i] );
        // sort by occurence
        Wlc_NtkPrintDistribSortOne( vTypes, vOccurs, i );
        Vec_WrdForEachEntry( vType, Sign, k )
        {
            Wlc_NtkPrintDistribFromSign( Sign, &s, &s0, &s1 );
            if ( ((k % 8) == 7 && s1) || ((k % 10) == 9 && !s1) )
                printf( "\n                        " );
            printf( "(%d)", (int)Vec_WrdEntry( vOccur, k ) );
            printf( "%s%d",      Abc_LitIsCompl(s)?"-":"",  Abc_Lit2Var(s) );
            if ( s0 )
                printf( "=%s%d", Abc_LitIsCompl(s0)?"-":"", Abc_Lit2Var(s0) );
            if ( s1 )
                printf( ".%s%d", Abc_LitIsCompl(s1)?"-":"", Abc_Lit2Var(s1) );
            printf( " " );
        }
        printf( "\n" );
    }
    Vec_VecFree( (Vec_Vec_t *)vTypes );
    Vec_VecFree( (Vec_Vec_t *)vOccurs );
}
void Wlc_NtkPrintNodes( Wlc_Ntk_t * p, int Type )
{
    Wlc_Obj_t * pObj; 
    int i, Counter = 0;
    printf( "Operation %s\n", Wlc_Names[Type] );
    Wlc_NtkForEachObj( p, pObj, i )
    {
        if ( (int)pObj->Type != Type )
            continue;
        printf( "%8d  :",      Counter++ );
        printf( "%8d  :  ",    i );
        printf( "%3d%s = ",    Wlc_ObjRange(pObj),                   Wlc_ObjIsSigned(pObj) ? "s" : " " );
        printf( "%3d%s  %s ",  Wlc_ObjRange(Wlc_ObjFanin0(p, pObj)), Wlc_ObjIsSigned(Wlc_ObjFanin0(p, pObj)) ? "s" : " ", Wlc_Names[Type] );
        printf( "%3d%s ",      Wlc_ObjRange(Wlc_ObjFanin1(p, pObj)), Wlc_ObjIsSigned(Wlc_ObjFanin1(p, pObj)) ? "s" : " " );
        printf( " :    " );
        printf( "%-12s =  ",   Wlc_ObjName(p, i) );
        printf( "%-12s  %s  ", Wlc_ObjName(p, Wlc_ObjFaninId0(pObj)), Wlc_Names[Type] );
        printf( "%-12s ",      Wlc_ObjName(p, Wlc_ObjFaninId1(pObj)) );
        printf( "\n" );
    }
}
void Wlc_NtkPrintStats( Wlc_Ntk_t * p, int fDistrib, int fVerbose )
{
    int i;
    printf( "%-20s : ",        p->pName );
    printf( "PI = %4d  ",      Wlc_NtkPiNum(p) );
    printf( "PO = %4d  ",      Wlc_NtkPoNum(p) );
    printf( "FF = %4d  ",      Wlc_NtkFfNum(p) );
    printf( "Obj = %6d  ",     Wlc_NtkObjNum(p) );
    printf( "Mem = %.3f MB",   1.0*Wlc_NtkMemUsage(p)/(1<<20) );
    printf( "\n" );
    if ( fDistrib )
    {
        Wlc_NtkPrintDistrib( p, fVerbose );
        return;
    }
    if ( !fVerbose )
        return;
    printf( "Node type statistics:\n" );
    for ( i = 1; i < WLC_OBJ_NUMBER; i++ )
    {
        if ( !p->nObjs[i] )
            continue;
        if ( p->nAnds[0] && p->nAnds[i] )
            printf( "%2d  :  %-8s  %6d  %7.2f %%\n", i, Wlc_Names[i], p->nObjs[i], 100.0*p->nAnds[i]/p->nAnds[0] );
        else
            printf( "%2d  :  %-8s  %6d\n", i, Wlc_Names[i], p->nObjs[i] );
    }
}

/**Function*************************************************************

  Synopsis    [Duplicates the network in a topological order.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Wlc_ObjCollectCopyFanins( Wlc_Ntk_t * p, int iObj, Vec_Int_t * vFanins )
{
    int i, iFanin;
    Wlc_Obj_t * pObj = Wlc_NtkObj( p, iObj );
    Vec_IntClear( vFanins );
    Wlc_ObjForEachFanin( pObj, iFanin, i )
        Vec_IntPush( vFanins, Wlc_ObjCopy(p, iFanin) );
    // special treatment of CONST and SELECT
    if ( pObj->Type == WLC_OBJ_CONST )
    {
        int * pInts = Wlc_ObjConstValue( pObj );
        int nInts = Abc_BitWordNum( Wlc_ObjRange(pObj) );
        for ( i = 0; i < nInts; i++ )
            Vec_IntPush( vFanins, pInts[i] );
    }
    else if ( pObj->Type == WLC_OBJ_BIT_SELECT || pObj->Type == WLC_OBJ_TABLE )
    {
        assert( Vec_IntSize(vFanins) == 1 );
        Vec_IntPush( vFanins, pObj->Fanins[1] );
    }
}
int Wlc_ObjDup( Wlc_Ntk_t * pNew, Wlc_Ntk_t * p, int iObj, Vec_Int_t * vFanins )
{
    Wlc_Obj_t * pObj = Wlc_NtkObj( p, iObj );
    int iFaninNew = Wlc_ObjAlloc( pNew, pObj->Type, Wlc_ObjIsSigned(pObj), pObj->End, pObj->Beg );
    Wlc_Obj_t * pObjNew = Wlc_NtkObj(pNew, iFaninNew);
    Wlc_ObjCollectCopyFanins( p, iObj, vFanins );
    Wlc_ObjAddFanins( pNew, pObjNew, vFanins );
    Wlc_ObjSetCopy( p, iObj, iFaninNew );
    return iFaninNew;
}
void Wlc_NtkDupDfs_rec( Wlc_Ntk_t * pNew, Wlc_Ntk_t * p, int iObj, Vec_Int_t * vFanins )
{
    Wlc_Obj_t * pObj;
    int i, iFanin;
    if ( Wlc_ObjCopy(p, iObj) )
        return;
    pObj = Wlc_NtkObj( p, iObj );
    Wlc_ObjForEachFanin( pObj, iFanin, i )
        Wlc_NtkDupDfs_rec( pNew, p, iFanin, vFanins );
    Wlc_ObjDup( pNew, p, iObj, vFanins );
}
Wlc_Ntk_t * Wlc_NtkDupDfs( Wlc_Ntk_t * p )
{
    Wlc_Ntk_t * pNew;
    Wlc_Obj_t * pObj;
    Vec_Int_t * vFanins;
    int i;
    Wlc_NtkCleanCopy( p );
    vFanins = Vec_IntAlloc( 100 );
    pNew = Wlc_NtkAlloc( p->pName, p->nObjsAlloc );
    Wlc_NtkForEachCi( p, pObj, i )
        Wlc_ObjDup( pNew, p, Wlc_ObjId(p, pObj), vFanins );
    Wlc_NtkForEachCo( p, pObj, i )
        Wlc_NtkDupDfs_rec( pNew, p, Wlc_ObjId(p, pObj), vFanins );
    Wlc_NtkForEachCo( p, pObj, i )
        Wlc_ObjSetCo( pNew, Wlc_ObjCopyObj(pNew, p, pObj), pObj->fIsFi );
    if ( p->vInits )
    pNew->vInits = Vec_IntDup( p->vInits );
    if ( p->pInits )
    pNew->pInits = Abc_UtilStrsav( p->pInits );
    Vec_IntFree( vFanins );
    return pNew;
}
void Wlc_NtkTransferNames( Wlc_Ntk_t * pNew, Wlc_Ntk_t * p )
{
    int i;
    assert( !Wlc_NtkHasCopy(pNew)   && Wlc_NtkHasCopy(p)   );
    assert( !Wlc_NtkHasNameId(pNew) && Wlc_NtkHasNameId(p) );
    assert( pNew->pManName  == NULL && p->pManName != NULL );
    Wlc_NtkCleanNameId( pNew );
    for ( i = 0; i < p->nObjsAlloc; i++ )
        if ( Wlc_ObjCopy(p, i) && i < Vec_IntSize(&p->vNameIds) && Wlc_ObjNameId(p, i) )
            Wlc_ObjSetNameId( pNew, Wlc_ObjCopy(p, i), Wlc_ObjNameId(p, i) );
    pNew->pManName = p->pManName; 
    p->pManName = NULL;
    Vec_IntErase( &p->vNameIds );
    // transfer table
    pNew->pMemTable = p->pMemTable;  p->pMemTable = NULL;
    pNew->vTables = p->vTables;      p->vTables = NULL;
}

////////////////////////////////////////////////////////////////////////
///                       END OF FILE                                ///
////////////////////////////////////////////////////////////////////////


ABC_NAMESPACE_IMPL_END