SQLite

** if there is an exact integer representation of the quantity.
*/
static void applyNumericAffinity(Mem *pRec, int bTryForInt){
  double rValue;
  i64 iValue;
  u8 enc = pRec->enc;
  if( (pRec->flags&MEM_Str)==0 ) return;
  if( (pRec->flags&(MEM_Int|MEM_Real))!=0 ) return;
  if( sqlite3AtoF(pRec->z, &rValue, pRec->n, enc)==0 ) return;
  if( 0==sqlite3Atoi64(pRec->z, &iValue, pRec->n, enc) ){
    pRec->u.i = iValue;
    pRec->flags |= MEM_Int;
  }else{
    pRec->u.r = rValue;
    pRec->flags |= MEM_Real;
    if( bTryForInt ) sqlite3VdbeIntegerAffinity(pRec);
  }
}

/*
** Processing is determine by the affinity parameter:

){
  applyAffinity((Mem *)pVal, affinity, enc);
}

/*
** pMem currently only holds a string type (or maybe a BLOB that we can
** interpret as a string if we want to).  Compute its corresponding
** numeric type, if has one.  Set the pMem->u.r and pMem->u.i fields
** accordingly.
*/
static u16 SQLITE_NOINLINE computeNumericType(Mem *pMem){
  assert( (pMem->flags & (MEM_Int|MEM_Real))==0 );
  assert( (pMem->flags & (MEM_Str|MEM_Blob))!=0 );
  if( sqlite3AtoF(pMem->z, &pMem->u.r, pMem->n, pMem->enc)==0 ){
    return 0;
  }
  if( sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc)==SQLITE_OK ){
    return MEM_Int;
  }
  return MEM_Real;
}

/*
** Return the numeric type for pMem, either MEM_Int or MEM_Real or both or
** 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) ){
    return pMem->flags & (MEM_Int|MEM_Real);
  }
  if( pMem->flags & (MEM_Str|MEM_Blob) ){
    return computeNumericType(pMem);

    printf(" NULL");
  }else if( (p->flags & (MEM_Int|MEM_Str))==(MEM_Int|MEM_Str) ){
    printf(" si:%lld", p->u.i);
  }else if( p->flags & MEM_Int ){
    printf(" i:%lld", p->u.i);
#ifndef SQLITE_OMIT_FLOATING_POINT
  }else if( p->flags & MEM_Real ){
    printf(" r:%g", p->u.r);
#endif
  }else if( p->flags & MEM_RowSet ){
    printf(" (rowset)");
  }else{
    char zBuf[200];
    sqlite3VdbeMemPrettyPrint(p, zBuf);
    printf(" %s", zBuf);

**
** P4 is a pointer to a 64-bit floating point value.
** Write that value into register P2.
*/
case OP_Real: {            /* same as TK_FLOAT, out2-prerelease */
  pOut->flags = MEM_Real;
  assert( !sqlite3IsNaN(*pOp->p4.pReal) );
  pOut->u.r = *pOp->p4.pReal;
  break;
}
#endif

/* Opcode: String8 * P2 * P4 *
** Synopsis: r[P2]='P4'
**

#ifdef SQLITE_OMIT_FLOATING_POINT
    pOut->u.i = rB;
    MemSetTypeFlag(pOut, MEM_Int);
#else
    if( sqlite3IsNaN(rB) ){
      goto arithmetic_result_is_null;
    }
    pOut->u.r = rB;
    MemSetTypeFlag(pOut, MEM_Real);
    if( ((type1|type2)&MEM_Real)==0 && !bIntint ){
      sqlite3VdbeIntegerAffinity(pOut);
    }
#endif
  }
  break;

      /* If the approximation iKey is larger than the actual real search
      ** term, substitute >= for > and < for <=. e.g. if the search term
      ** is 4.9 and the integer approximation 5:
      **
      **        (x >  4.9)    ->     (x >= 5)
      **        (x <= 4.9)    ->     (x <  5)
      */
      if( pIn3->u.r<(double)iKey ){
        assert( OP_SeekGE==(OP_SeekGT-1) );
        assert( OP_SeekLT==(OP_SeekLE-1) );
        assert( (OP_SeekLE & 0x0001)==(OP_SeekGT & 0x0001) );
        if( (oc & 0x0001)==(OP_SeekGT & 0x0001) ) oc--;
      }

      /* If the approximation iKey is smaller than the actual real search
      ** term, substitute <= for < and > for >=.  */
      else if( pIn3->u.r>(double)iKey ){
        assert( OP_SeekLE==(OP_SeekLT+1) );
        assert( OP_SeekGT==(OP_SeekGE+1) );
        assert( (OP_SeekLT & 0x0001)==(OP_SeekGE & 0x0001) );
        if( (oc & 0x0001)==(OP_SeekLT & 0x0001) ) oc++;
      }
    } 
    rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)iKey, 0, &res);

/*
** Internally, the vdbe manipulates nearly all SQL values as Mem
** structures. Each Mem struct may cache multiple representations (string,
** integer etc.) of the same value.
*/
struct Mem {
  union MemValue {
    double r;           /* Real value used when MEM_Realis set in flags */
    i64 i;              /* Integer value used when MEM_Int is set in flags */
    int nZero;          /* Used when bit MEM_Zero is set in flags */
    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
  } u;
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
  int n;              /* Number of characters in string value, excluding '\0' */

  char *z;            /* String or BLOB value */

  /* ShallowCopy only needs to copy the information above */
  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
  sqlite3 *db;        /* The associated database connection */
  void (*xDel)(void*);/* Destructor for Mem.z - only valid if MEM_Dyn */
#ifdef SQLITE_DEBUG
  Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
  void *pFiller;      /* So that sizeof(Mem) is a multiple of 8 */
#endif
};

    __attribute__((aligned(8))) 
#endif
    = {
        /* .u          = */ {0},
        /* .flags      = */ MEM_Null,
        /* .enc        = */ 0,
        /* .n          = */ 0,

        /* .z          = */ 0,
        /* .zMalloc    = */ 0,
        /* .db         = */ 0,
        /* .xDel       = */ 0,
#ifdef SQLITE_DEBUG
        /* .pScopyFrom = */ 0,
        /* .pFiller    = */ 0,

  int rc;
  switch( sqlite3_value_type((sqlite3_value*)pValue) ){
    case SQLITE_INTEGER: {
      rc = sqlite3_bind_int64(pStmt, i, pValue->u.i);
      break;
    }
    case SQLITE_FLOAT: {
      rc = sqlite3_bind_double(pStmt, i, pValue->u.r);
      break;
    }
    case SQLITE_BLOB: {
      if( pValue->flags & MEM_Zero ){
        rc = sqlite3_bind_zeroblob(pStmt, i, pValue->u.nZero);
      }else{
        rc = sqlite3_bind_blob(pStmt, i, pValue->z, pValue->n,SQLITE_TRANSIENT);

    case P4_MEM: {
      Mem *pMem = pOp->p4.pMem;
      if( pMem->flags & MEM_Str ){
        zP4 = pMem->z;
      }else if( pMem->flags & MEM_Int ){
        sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
      }else if( pMem->flags & MEM_Real ){
        sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->u.r);
      }else if( pMem->flags & MEM_Null ){
        sqlite3_snprintf(nTemp, zTemp, "NULL");
      }else{
        assert( pMem->flags & MEM_Blob );
        zP4 = "(blob)";
      }
      break;

  u32 len;

  /* Integer and Real */
  if( serial_type<=7 && serial_type>0 ){
    u64 v;
    u32 i;
    if( serial_type==7 ){
      assert( sizeof(v)==sizeof(pMem->u.r) );
      memcpy(&v, &pMem->u.r, sizeof(v));
      swapMixedEndianFloat(v);
    }else{
      v = pMem->u.i;
    }
    len = i = sqlite3VdbeSerialTypeLen(serial_type);
    assert( i>0 );
    do{

    */
    static const u64 t1 = ((u64)0x3ff00000)<<32;
    static const double r1 = 1.0;
    u64 t2 = t1;
    swapMixedEndianFloat(t2);
    assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
#endif
    assert( sizeof(x)==8 && sizeof(pMem->u.r)==8 );
    swapMixedEndianFloat(x);
    memcpy(&pMem->u.r, &x, sizeof(x));
    pMem->flags = sqlite3IsNaN(pMem->u.r) ? MEM_Null : MEM_Real;
  }
  return 8;
}
u32 sqlite3VdbeSerialGet(
  const unsigned char *buf,     /* Buffer to deserialize from */
  u32 serial_type,              /* Serial type to deserialize */
  Mem *pMem                     /* Memory cell to write value into */

    double r1, r2;
    if( (f1 & f2 & MEM_Int)!=0 ){
      if( pMem1->u.i < pMem2->u.i ) return -1;
      if( pMem1->u.i > pMem2->u.i ) return 1;
      return 0;
    }
    if( (f1&MEM_Real)!=0 ){
      r1 = pMem1->u.r;
    }else if( (f1&MEM_Int)!=0 ){
      r1 = (double)pMem1->u.i;
    }else{
      return 1;
    }
    if( (f2&MEM_Real)!=0 ){
      r2 = pMem2->u.r;
    }else if( (f2&MEM_Int)!=0 ){
      r2 = (double)pMem2->u.i;
    }else{
      return -1;
    }
    if( r1<r2 ) return -1;
    if( r1>r2 ) return 1;

      if( serial_type>=12 ){
        rc = +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else if( serial_type==7 ){
        double rhs = (double)pRhs->u.i;
        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
        if( mem1.u.r<rhs ){
          rc = -1;
        }else if( mem1.u.r>rhs ){
          rc = +1;
        }
      }else{
        i64 lhs = vdbeRecordDecodeInt(serial_type, &aKey1[d1]);
        i64 rhs = pRhs->u.i;
        if( lhs<rhs ){
          rc = -1;

    else if( pRhs->flags & MEM_Real ){
      serial_type = aKey1[idx1];
      if( serial_type>=12 ){
        rc = +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else{
        double rhs = pRhs->u.r;
        double lhs;
        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
        if( serial_type==7 ){
          lhs = mem1.u.r;
        }else{
          lhs = (double)mem1.u.i;
        }
        if( lhs<rhs ){
          rc = -1;
        }else if( lhs>rhs ){
          rc = +1;

*/
int sqlite3VdbeCheckMemInvariants(Mem *p){
  /* If MEM_Dyn is set then Mem.xDel!=0.  
  ** Mem.xDel is might not be initialized if MEM_Dyn is clear.
  */
  assert( (p->flags & MEM_Dyn)==0 || p->xDel!=0 );

  /* Cannot be both MEM_Int and MEM_Real at the same time */
  assert( (p->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) );

  /* If p holds a string or blob, the Mem.z must point to exactly
  ** one of the following:
  **
  **   (1) Memory in Mem.zMalloc and managed by the Mem object
  **   (2) Memory to be freed using Mem.xDel
  **   (3) An ephemeral string or blob
  **   (4) A static string or blob

  ** 
  ** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16.
  */
  if( fg & MEM_Int ){
    sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
  }else{
    assert( fg & MEM_Real );
    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->u.r);
  }
  pMem->n = sqlite3Strlen30(pMem->z);
  pMem->enc = SQLITE_UTF8;
  pMem->flags |= MEM_Str|MEM_Term;
  if( bForce ) pMem->flags &= ~(MEM_Int|MEM_Real);
  sqlite3VdbeChangeEncoding(pMem, enc);
  return SQLITE_OK;

  int flags;
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  flags = pMem->flags;
  if( flags & MEM_Int ){
    return pMem->u.i;
  }else if( flags & MEM_Real ){
    return doubleToInt64(pMem->u.r);
  }else if( flags & (MEM_Str|MEM_Blob) ){
    i64 value = 0;
    assert( pMem->z || pMem->n==0 );
    sqlite3Atoi64(pMem->z, &value, pMem->n, pMem->enc);
    return value;
  }else{
    return 0;
  }
}

/*
** Return the best representation of pMem that we can get into a
** double.  If pMem is already a double or an integer, return its
** value.  If it is a string or blob, try to convert it to a double.
** If it is a NULL, return 0.0.
*/
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 ){
    return (double)pMem->u.i;
  }else if( pMem->flags & (MEM_Str|MEM_Blob) ){
    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
    double val = (double)0;
    sqlite3AtoF(pMem->z, &val, pMem->n, pMem->enc);
    return val;
  }else{
    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
    return (double)0;
  }
}

/*
** The MEM structure is already a MEM_Real.  Try to also make it a
** MEM_Int if we can.
*/
void sqlite3VdbeIntegerAffinity(Mem *pMem){
  i64 ix;
  assert( pMem->flags & MEM_Real );
  assert( (pMem->flags & MEM_RowSet)==0 );
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );

  ix = doubleToInt64(pMem->u.r);

  /* Only mark the value as an integer if
  **
  **    (1) the round-trip conversion real->int->real is a no-op, and
  **    (2) The integer is neither the largest nor the smallest
  **        possible integer (ticket #3922)
  **
  ** The second and third terms in the following conditional enforces
  ** the second condition under the assumption that addition overflow causes
  ** values to wrap around.
  */

  if( pMem->u.r==ix && ix>SMALLEST_INT64 && ix<LARGEST_INT64 ){
    pMem->u.i = ix;

    MemSetTypeFlag(pMem, MEM_Int);
  }
}

/*
** Convert pMem to type integer.  Invalidate any prior representations.
*/
int sqlite3VdbeMemIntegerify(Mem *pMem){

** Convert pMem so that it is of type MEM_Real.
** Invalidate any prior representations.
*/
int sqlite3VdbeMemRealify(Mem *pMem){
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );

  pMem->u.r = sqlite3VdbeRealValue(pMem);
  MemSetTypeFlag(pMem, MEM_Real);
  return SQLITE_OK;
}

/*
** Convert pMem so that it has types MEM_Real or MEM_Int or both.
** 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){
  if( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))==0 ){
    assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 );
    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
    if( 0==sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc) ){
      MemSetTypeFlag(pMem, MEM_Int);
    }else{
      pMem->u.r = sqlite3VdbeRealValue(pMem);
      MemSetTypeFlag(pMem, MEM_Real);
      sqlite3VdbeIntegerAffinity(pMem);
    }
  }
  assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))!=0 );
  pMem->flags &= ~(MEM_Str|MEM_Blob);
  return SQLITE_OK;

/*
** Delete any previous value and set the value stored in *pMem to val,
** manifest type REAL.
*/
void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
  sqlite3VdbeMemSetNull(pMem);
  if( !sqlite3IsNaN(val) ){
    pMem->u.r = val;
    pMem->flags = MEM_Real;
  }
}
#endif

/*
** Delete any previous value and set the value of pMem to be an

    }
  }else if( op==TK_UMINUS ) {
    /* This branch happens for multiple negative signs.  Ex: -(-5) */
    if( SQLITE_OK==sqlite3ValueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal) 
     && pVal!=0
    ){
      sqlite3VdbeMemNumerify(pVal);
      if( pVal->flags & MEM_Real ){
        pVal->u.r = -pVal->u.r;
      }else if( pVal->u.i==SMALLEST_INT64 ){


        pVal->u.r = -(double)SMALLEST_INT64;
        MemSetTypeFlag(pVal, MEM_Real);
      }else{
        pVal->u.i = -pVal->u.i;
      }

      sqlite3ValueApplyAffinity(pVal, affinity, enc);
    }
  }else if( op==TK_NULL ){
    pVal = valueNew(db, pCtx);
    if( pVal==0 ) goto no_mem;
  }
#ifndef SQLITE_OMIT_BLOB_LITERAL

      assert( idx>0 && idx<=p->nVar );
      pVar = &p->aVar[idx-1];
      if( pVar->flags & MEM_Null ){
        sqlite3StrAccumAppend(&out, "NULL", 4);
      }else if( pVar->flags & MEM_Int ){
        sqlite3XPrintf(&out, 0, "%lld", pVar->u.i);
      }else if( pVar->flags & MEM_Real ){
        sqlite3XPrintf(&out, 0, "%!.15g", pVar->u.r);
      }else if( pVar->flags & MEM_Str ){
        int nOut;  /* Number of bytes of the string text to include in output */
#ifndef SQLITE_OMIT_UTF16
        u8 enc = ENC(db);
        Mem utf8;
        if( enc!=SQLITE_UTF8 ){
          memset(&utf8, 0, sizeof(utf8));