assert( z[n]=='\'' );
      zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
      sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
      break;
    }
#endif
    case TK_VARIABLE: {
      VdbeOp *pOp;
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      assert( pExpr->u.zToken!=0 );
      assert( pExpr->u.zToken[0]!=0 );
      if( pExpr->u.zToken[1]==0
         && (pOp = sqlite3VdbeGetOp(v, -1))->opcode==OP_Variable
         && pOp->p1+pOp->p3==pExpr->iColumn
         && pOp->p2+pOp->p3==target
         && pOp->p4.z==0
      ){
        /* If the previous instruction was a copy of the previous unnamed
        ** parameter into the previous register, then simply increment the
        ** repeat count on the prior instruction rather than making a new
        ** instruction.
        */
        pOp->p3++;
      }else{
        sqlite3VdbeAddOp3(v, OP_Variable, pExpr->iColumn, target, 1);
        if( pExpr->u.zToken[1]!=0 ){
          sqlite3VdbeChangeP4(v, -1, pExpr->u.zToken, 0);
        }
      }
      break;
    }
    case TK_REGISTER: {
      inReg = pExpr->iTable;
      break;
    }

      assert( z[n]=='\'' );
      zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
      sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
      break;
    }
#endif
    case TK_VARIABLE: {

      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      assert( pExpr->u.zToken!=0 );
      assert( pExpr->u.zToken[0]!=0 );













      sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iColumn, target);
      if( pExpr->u.zToken[1]!=0 ){
        sqlite3VdbeChangeP4(v, -1, pExpr->u.zToken, 0);

      }
      break;
    }
    case TK_REGISTER: {
      inReg = pExpr->iTable;
      break;
    }

  assert( pOp->p1 <= SQLITE_MAX_LENGTH );
  sqlite3VdbeMemSetStr(pOut, pOp->p4.z, pOp->p1, 0, 0);
  pOut->enc = encoding;
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Variable P1 P2 P3 P4 *
**
** Transfer the values of bound parameters P1..P1+P3-1 into registers
** P2..P2+P3-1.
**
** If the parameter is named, then its name appears in P4 and P3==1.
** The P4 value is used by sqlite3_bind_parameter_name().
*/
case OP_Variable: {
  int p1;          /* Variable to copy from */
  int p2;          /* Register to copy to */
  int n;           /* Number of values left to copy */
  Mem *pVar;       /* Value being transferred */

  p1 = pOp->p1 - 1;
  p2 = pOp->p2;
  n = pOp->p3;
  assert( p1>=0 && p1+n<=p->nVar );
  assert( p2>=1 && p2+n-1<=p->nMem );
  assert( pOp->p4.z==0 || pOp->p3==1 || pOp->p3==0 );

  while( n-- > 0 ){

    pVar = &p->aVar[p1++];
    if( sqlite3VdbeMemTooBig(pVar) ){
      goto too_big;
    }
    pOut = &aMem[p2++];
    sqlite3VdbeMemReleaseExternal(pOut);
    pOut->flags = MEM_Null;
    sqlite3VdbeMemShallowCopy(pOut, pVar, MEM_Static);
    UPDATE_MAX_BLOBSIZE(pOut);
  }
  break;
}

/* Opcode: Move P1 P2 P3 * *
**
** Move the values in register P1..P1+P3-1 over into
** registers P2..P2+P3-1.  Registers P1..P1+P1-1 are

  assert( pOp->p1 <= SQLITE_MAX_LENGTH );
  sqlite3VdbeMemSetStr(pOut, pOp->p4.z, pOp->p1, 0, 0);
  pOut->enc = encoding;
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Variable P1 P2 * P4 *
**
** Transfer the values of bound parameter P1 into register P2

**
** If the parameter is named, then its name appears in P4 and P3==1.
** The P4 value is used by sqlite3_bind_parameter_name().
*/
case OP_Variable: {            /* out2-prerelease */



  Mem *pVar;       /* Value being transferred */









  assert( pOp->p1>0 && pOp->p1<=p->nVar );
  pVar = &p->aVar[pOp->p1 - 1];
  if( sqlite3VdbeMemTooBig(pVar) ){
    goto too_big;
  }



  sqlite3VdbeMemShallowCopy(pOut, pVar, MEM_Static);
  UPDATE_MAX_BLOBSIZE(pOut);

  break;
}

/* Opcode: Move P1 P2 P3 * *
**
** Move the values in register P1..P1+P3-1 over into
** registers P2..P2+P3-1.  Registers P1..P1+P1-1 are

# 2010 May 12
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script testing a bug found in the OP_Variable optimizer
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_test bug-20100512-1 {
  set DB [sqlite3_connection_pointer db]
  set SQL {SELECT case when 1 then 99 else ? end + ?}
  set STMT [sqlite3_prepare_v2 $DB $SQL -1 TAIL]
  set TAIL
} {}
do_test bug-20100512-2 {
  sqlite3_bind_parameter_count $STMT
} 2
do_test bug-20100512-3 {
  sqlite3_bind_int $STMT 1 123
  sqlite3_bind_int $STMT 2 456
  sqlite3_step $STMT
  sqlite3_column_int $STMT 0
} {555}
sqlite3_finalize $STMT