SQLite

    /* Only attempt the conversion to TEXT if there is an integer or real
    ** representation (blob and NULL do not get converted) but no string
    ** representation.  It would be harmless to repeat the conversion if 
    ** there is already a string rep, but it is pointless to waste those
    ** CPU cycles. */
    if( 0==(pRec->flags&MEM_Str) ){ /*OPTIMIZATION-IF-FALSE*/
      if( (pRec->flags&(MEM_Real|MEM_Int|MEM_IntReal)) ){
        testcase( pRec->flags & MEM_Int );
        testcase( pRec->flags & MEM_Real );
        testcase( pRec->flags & MEM_IntReal );
        sqlite3VdbeMemStringify(pRec, enc, 1);
      }
    }
    pRec->flags &= ~(MEM_Real|MEM_Int|MEM_IntReal);
  }
}

** none.  
**
** Unlike applyNumericAffinity(), this routine does not modify pMem->flags.
** But it does set pMem->u.r and pMem->u.i appropriately.
*/
static u16 numericType(Mem *pMem){
  if( pMem->flags & (MEM_Int|MEM_Real|MEM_IntReal) ){
    testcase( pMem->flags & MEM_Int );
    testcase( pMem->flags & MEM_Real );
    testcase( pMem->flags & MEM_IntReal );
    return pMem->flags & (MEM_Int|MEM_Real|MEM_IntReal);
  }
  if( pMem->flags & (MEM_Str|MEM_Blob) ){
    testcase( pMem->flags & MEM_Str );
    testcase( pMem->flags & MEM_Blob );
    return computeNumericType(pMem);
  }
  return 0;
}

#ifdef SQLITE_DEBUG
/*

** has REAL affinity.  Such column values may still be stored as
** integers, for space efficiency, but after extraction we want them
** to have only a real value.
*/
case OP_RealAffinity: {                  /* in1 */
  pIn1 = &aMem[pOp->p1];
  if( pIn1->flags & (MEM_Int|MEM_IntReal) ){
    testcase( pIn1->flags & MEM_Int );
    testcase( pIn1->flags & MEM_IntReal );
    sqlite3VdbeMemRealify(pIn1);
  }
  break;
}
#endif

#ifndef SQLITE_OMIT_CAST

case OP_SeekRowid: {        /* jump, in3 */
  VdbeCursor *pC;
  BtCursor *pCrsr;
  int res;
  u64 iKey;

  pIn3 = &aMem[pOp->p3];
  testcase( pIn3->flags & MEM_Int );
  testcase( pIn3->flags & MEM_IntReal );
  if( (pIn3->flags & (MEM_Int|MEM_IntReal))==0 ){
    /* Make sure pIn3->u.i contains a valid integer representation of
    ** the key value, but do not change the datatype of the register, as
    ** other parts of the perpared statement might be depending on the
    ** current datatype. */
    u16 origFlags = pIn3->flags;
    int isNotInt;

  pMem = *ppValue = &p->pUnpacked->aMem[iIdx];
  if( iIdx==p->pTab->iPKey ){
    sqlite3VdbeMemSetInt64(pMem, p->iKey1);
  }else if( iIdx>=p->pUnpacked->nField ){
    *ppValue = (sqlite3_value *)columnNullValue();
  }else if( p->pTab->aCol[iIdx].affinity==SQLITE_AFF_REAL ){
    if( pMem->flags & (MEM_Int|MEM_IntReal) ){
      testcase( pMem->flags & MEM_Int );
      testcase( pMem->flags & MEM_IntReal );
      sqlite3VdbeMemRealify(pMem);
    }
  }

 preupdate_old_out:
  sqlite3Error(db, rc);
  return sqlite3ApiExit(db, rc);

    return 0;
  }
  if( flags&(MEM_Int|MEM_IntReal) ){
    /* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */
#   define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
    i64 i = pMem->u.i;
    u64 u;
    testcase( flags & MEM_Int );
    testcase( flags & MEM_IntReal );
    if( i<0 ){
      u = ~i;
    }else{
      u = i;
    }
    if( u<=127 ){
      if( (i&1)==i && file_format>=4 ){

  if( combined_flags&MEM_Null ){
    return (f2&MEM_Null) - (f1&MEM_Null);
  }

  /* At least one of the two values is a number
  */
  if( combined_flags&(MEM_Int|MEM_Real|MEM_IntReal) ){
    testcase( combined_flags & MEM_Int );
    testcase( combined_flags & MEM_Real );
    testcase( combined_flags & MEM_IntReal );
    if( (f1 & f2 & (MEM_Int|MEM_IntReal))!=0 ){
      testcase( f1 & f2 & MEM_Int );
      testcase( f1 & f2 & MEM_IntReal );
      if( pMem1->u.i < pMem2->u.i ) return -1;
      if( pMem1->u.i > pMem2->u.i ) return +1;
      return 0;
    }
    if( (f1 & f2 & MEM_Real)!=0 ){
      if( pMem1->u.r < pMem2->u.r ) return -1;
      if( pMem1->u.r > pMem2->u.r ) return +1;
      return 0;
    }
    if( (f1&(MEM_Int|MEM_IntReal))!=0 ){
      testcase( f1 & MEM_Int );
      testcase( f1 & MEM_IntReal );
      if( (f2&MEM_Real)!=0 ){
        return sqlite3IntFloatCompare(pMem1->u.i, pMem2->u.r);
      }else if( (f2&(MEM_Int|MEM_IntReal))!=0 ){
        if( pMem1->u.i < pMem2->u.i ) return -1;
        if( pMem1->u.i > pMem2->u.i ) return +1;
        return 0;
      }else{
        return -1;
      }
    }
    if( (f1&MEM_Real)!=0 ){
      if( (f2&(MEM_Int|MEM_IntReal))!=0 ){
        testcase( f2 & MEM_Int );
        testcase( f2 & MEM_IntReal );
        return -sqlite3IntFloatCompare(pMem2->u.i, pMem1->u.r);
      }else{
        return -1;
      }
    }
    return +1;
  }

  assert( pPKey2->pKeyInfo->nKeyField>0 );
  assert( idx1<=szHdr1 || CORRUPT_DB );
  do{
    u32 serial_type;

    /* RHS is an integer */
    if( pRhs->flags & (MEM_Int|MEM_IntReal) ){
      testcase( pRhs->flags & MEM_Int );
      testcase( pRhs->flags & MEM_IntReal );
      serial_type = aKey1[idx1];
      testcase( serial_type==12 );
      if( serial_type>=10 ){
        rc = +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else if( serial_type==7 ){

}
i64 sqlite3VdbeIntValue(Mem *pMem){
  int flags;
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  flags = pMem->flags;
  if( flags & (MEM_Int|MEM_IntReal) ){
    testcase( flags & MEM_IntReal );
    return pMem->u.i;
  }else if( flags & MEM_Real ){
    return doubleToInt64(pMem->u.r);
  }else if( flags & (MEM_Str|MEM_Blob) ){
    assert( pMem->z || pMem->n==0 );
    return memIntValue(pMem);
  }else{

}
double sqlite3VdbeRealValue(Mem *pMem){
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  if( pMem->flags & MEM_Real ){
    return pMem->u.r;
  }else if( pMem->flags & (MEM_Int|MEM_IntReal) ){
    testcase( pMem->flags & MEM_IntReal );
    return (double)pMem->u.i;
  }else if( pMem->flags & (MEM_Str|MEM_Blob) ){
    return memRealValue(pMem);
  }else{
    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
    return (double)0;
  }
}

/*
** Return 1 if pMem represents true, and return 0 if pMem represents false.
** Return the value ifNull if pMem is NULL.  
*/
int sqlite3VdbeBooleanValue(Mem *pMem, int ifNull){
  testcase( pMem->flags & MEM_IntReal );
  if( pMem->flags & (MEM_Int|MEM_IntReal) ) return pMem->u.i!=0;
  if( pMem->flags & MEM_Null ) return ifNull;
  return sqlite3VdbeRealValue(pMem)!=0.0;
}

/*
** The MEM structure is already a MEM_Real.  Try to also make it a

** Invalidate any prior representations.
**
** Every effort is made to force the conversion, even if the input
** is a string that does not look completely like a number.  Convert
** as much of the string as we can and ignore the rest.
*/
int sqlite3VdbeMemNumerify(Mem *pMem){
  testcase( pMem->flags & MEM_Int );
  testcase( pMem->flags & MEM_Real );
  testcase( pMem->flags & MEM_IntReal );
  testcase( pMem->flags & MEM_Null );
  if( (pMem->flags & (MEM_Int|MEM_Real|MEM_IntReal|MEM_Null))==0 ){
    int rc;
    assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 );
    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
    rc = sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc);
    if( rc==0 ){
      MemSetTypeFlag(pMem, MEM_Int);

      sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC);
    }
    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_BLOB ){
      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, SQLITE_UTF8);
    }else{
      sqlite3ValueApplyAffinity(pVal, affinity, SQLITE_UTF8);
    }
    assert( (pVal->flags & MEM_IntReal)==0 );
    if( pVal->flags & (MEM_Int|MEM_IntReal|MEM_Real) ) pVal->flags &= ~MEM_Str;
    if( pVal->flags & (MEM_Int|MEM_IntReal|MEM_Real) ){
      testcase( pVal->flags & MEM_Int );
      testcase( pVal->flags & MEM_Real );
      pVal->flags &= ~MEM_Str;
    }
    if( enc!=SQLITE_UTF8 ){
      rc = sqlite3VdbeChangeEncoding(pVal, enc);
    }
  }else if( op==TK_UMINUS ) {
    /* This branch happens for multiple negative signs.  Ex: -(-5) */
    if( SQLITE_OK==valueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal,pCtx) 
     && pVal!=0