SQLite

  pIn1->u.i = (int)(pOp - aOp);
  REGISTER_TRACE(pOp->p1, pIn1);
  pOp = &aOp[pcDest];
  break;
}

/* Opcode:  HaltIfNull  P1 P2 P3 P4 P5
** Synopsis: if r[P3]=null halt
**
** Check the value in register P3.  If it is NULL then Halt using
** parameter P1, P2, and P4 as if this were a Halt instruction.  If the
** value in register P3 is not NULL, then this routine is a no-op.
** The P5 parameter should be 1.
*/
case OP_HaltIfNull: {      /* in3 */

    if( pIn3->u.i==pOp->p5 ) pOut->flags = MEM_Blob|MEM_Static|MEM_Term;
  }
#endif
  break;
}

/* Opcode: Null P1 P2 P3 * *
** Synopsis: r[P2..P3]=NULL
**
** Write a NULL into registers P2.  If P3 greater than P2, then also write
** NULL into register P3 and every register in between P2 and P3.  If P3
** is less than P2 (typically P3 is zero) then only register P2 is
** set to NULL.
**
** If the P1 value is non-zero, then also set the MEM_Cleared flag so that

    pOut->flags = nullFlag;
    cnt--;
  }
  break;
}

/* Opcode: SoftNull P1 * * * *
** Synopsis: r[P1]=NULL
**
** Set register P1 to have the value NULL as seen by the OP_MakeRecord
** instruction, but do not free any string or blob memory associated with
** the register, so that if the value was a string or blob that was
** previously copied using OP_SCopy, the copies will continue to be valid.
*/
case OP_SoftNull: {

  pOut = out2Prerelease(p, pOp);
  sqlite3VdbeMemShallowCopy(pOut, pVar, MEM_Static);
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Move P1 P2 P3 * *
** Synopsis: r[P2@P3]=r[P1@P3]
**
** Move the P3 values in register P1..P1+P3-1 over into
** registers P2..P2+P3-1.  Registers P1..P1+P3-1 are
** left holding a NULL.  It is an error for register ranges
** P1..P1+P3-1 and P2..P2+P3-1 to overlap.  It is an error
** for P3 to be less than 1.
*/

  assert( (pIn1->flags & MEM_Int)!=0 );
  pOut = &aMem[pOp->p2];
  sqlite3VdbeMemSetInt64(pOut, pIn1->u.i);
  break;
}

/* Opcode: ResultRow P1 P2 * * *
** Synopsis: output=r[P1@P2]
**
** The registers P1 through P1+P2-1 contain a single row of
** results. This opcode causes the sqlite3_step() call to terminate
** with an SQLITE_ROW return code and it sets up the sqlite3_stmt
** structure to provide access to the r(P1)..r(P1+P2-1) values as
** the result row.
*/

  pOut->n = (int)nByte;
  pOut->enc = encoding;
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Add P1 P2 P3 * *
** Synopsis: r[P3]=r[P1]+r[P2]
**
** Add the value in register P1 to the value in register P2
** and store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: Multiply P1 P2 P3 * *
** Synopsis: r[P3]=r[P1]*r[P2]
**
**
** Multiply the value in register P1 by the value in register P2
** and store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: Subtract P1 P2 P3 * *
** Synopsis: r[P3]=r[P2]-r[P1]
**
** Subtract the value in register P1 from the value in register P2
** and store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: Divide P1 P2 P3 * *
** Synopsis: r[P3]=r[P2]/r[P1]
**
** Divide the value in register P1 by the value in register P2
** and store the result in register P3 (P3=P2/P1). If the value in 
** register P1 is zero, then the result is NULL. If either input is 
** NULL, the result is NULL.
*/
/* Opcode: Remainder P1 P2 P3 * *
** Synopsis: r[P3]=r[P2]%r[P1]
**
** Compute the remainder after integer register P2 is divided by 
** register P1 and store the result in register P3. 
** If the value in register P1 is zero the result is NULL.
** If either operand is NULL, the result is NULL.
*/
case OP_Add:                   /* same as TK_PLUS, in1, in2, out3 */

  REGISTER_TRACE(pOp->p3, pCtx->pOut);
  UPDATE_MAX_BLOBSIZE(pCtx->pOut);
  break;
}

/* Opcode: BitAnd P1 P2 P3 * *
** Synopsis: r[P3]=r[P1]&r[P2]
**
** Take the bit-wise AND of the values in register P1 and P2 and
** store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: BitOr P1 P2 P3 * *
** Synopsis: r[P3]=r[P1]|r[P2]
**
** Take the bit-wise OR of the values in register P1 and P2 and
** store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: ShiftLeft P1 P2 P3 * *
** Synopsis: r[P3]=r[P2]<<r[P1]
**
** Shift the integer value in register P2 to the left by the
** number of bits specified by the integer in register P1.
** Store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: ShiftRight P1 P2 P3 * *
** Synopsis: r[P3]=r[P2]>>r[P1]
**
** Shift the integer value in register P2 to the right by the
** number of bits specified by the integer in register P1.
** Store the result in register P3.
** If either input is NULL, the result is NULL.
*/
case OP_BitAnd:                 /* same as TK_BITAND, in1, in2, out3 */

  }
  pOut->u.i = iA;
  MemSetTypeFlag(pOut, MEM_Int);
  break;
}

/* Opcode: AddImm  P1 P2 * * *
** Synopsis: r[P1]=r[P1]+P2
** 
** Add the constant P2 to the value in register P1.
** The result is always an integer.
**
** To force any register to be an integer, just add 0.
*/
case OP_AddImm: {            /* in1 */

  UPDATE_MAX_BLOBSIZE(pIn1);
  if( rc ) goto abort_due_to_error;
  break;
}
#endif /* SQLITE_OMIT_CAST */

/* Opcode: Eq P1 P2 P3 P4 P5
** Synopsis: IF r[P1]==r[P3]
**
** Compare the values in register P1 and P3.  If reg(P3)==reg(P1) then
** jump to address P2.  Or if the SQLITE_STOREP2 flag is set in P5, then
** store the result of comparison in register P2.
**
** The SQLITE_AFF_MASK portion of P5 must be an affinity character -
** SQLITE_AFF_TEXT, SQLITE_AFF_INTEGER, and so forth. An attempt is made 

** If neither operand is NULL the result is the same as it would be if
** the SQLITE_NULLEQ flag were omitted from P5.
**
** If both SQLITE_STOREP2 and SQLITE_KEEPNULL flags are set then the
** content of r[P2] is only set to 1 (true) if it was not previously NULL.
*/
/* Opcode: Ne P1 P2 P3 P4 P5
** Synopsis: IF r[P1]!=r[P3]
**
** This works just like the Eq opcode except that the jump is taken if
** the operands in registers P1 and P3 are not equal.  See the Eq opcode for
** additional information.
**
** If both SQLITE_STOREP2 and SQLITE_KEEPNULL flags are set then the
** content of r[P2] is only set to 0 (false) if it was not previously NULL.
*/
/* Opcode: Lt P1 P2 P3 P4 P5
** Synopsis: IF r[P1]<r[P3]
**
** Compare the values in register P1 and P3.  If reg(P3)<reg(P1) then
** jump to address P2.  Or if the SQLITE_STOREP2 flag is set in P5 store
** the result of comparison (0 or 1 or NULL) into register P2.
**
** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
** reg(P3) is NULL then the take the jump.  If the SQLITE_JUMPIFNULL 

** P4 is  used to do the comparison.  If P4 is not specified then
** memcmp() is used to compare text string.  If both values are
** numeric, then a numeric comparison is used. If the two values
** are of different types, then numbers are considered less than
** strings and strings are considered less than blobs.
*/
/* Opcode: Le P1 P2 P3 P4 P5
** Synopsis: IF r[P1]<=r[P3]
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is less than or equal to the content of
** register P1.  See the Lt opcode for additional information.
*/
/* Opcode: Gt P1 P2 P3 P4 P5
** Synopsis: IF r[P1]>r[P3]
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is greater than the content of
** register P1.  See the Lt opcode for additional information.
*/
/* Opcode: Ge P1 P2 P3 P4 P5
** Synopsis: IF r[P1]>=r[P3]
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is greater than or equal to the content of
** register P1.  See the Lt opcode for additional information.
*/
case OP_Eq:               /* same as TK_EQ, jump, in1, in3 */
case OP_Ne:               /* same as TK_NE, jump, in1, in3 */

  if( c ){
    goto jump_to_p2;
  }
  break;
}

/* Opcode: IsNull P1 P2 * * *
** Synopsis: if r[P1]==NULL goto P2
**
** Jump to P2 if the value in register P1 is NULL.
*/
case OP_IsNull: {            /* same as TK_ISNULL, jump, in1 */
  pIn1 = &aMem[pOp->p1];
  VdbeBranchTaken( (pIn1->flags & MEM_Null)!=0, 2);
  if( (pIn1->flags & MEM_Null)!=0 ){

  if( (pIn1->flags & MEM_Null)==0 ){
    goto jump_to_p2;
  }
  break;
}

/* Opcode: Column P1 P2 P3 P4 P5
** Synopsis: r[P3]=PX
**
** Interpret the data that cursor P1 points to as a structure built using
** the MakeRecord instruction.  (See the MakeRecord opcode for additional
** information about the format of the data.)  Extract the P2-th column
** from this record.  If there are less that (P2+1) 
** values in the record, extract a NULL.
**

** value of register P2 will then change.  Make sure this does not
** cause any problems.)
**
** This instruction only works on tables.  The equivalent instruction
** for indices is OP_IdxInsert.
*/
/* Opcode: InsertInt P1 P2 P3 P4 P5
** Synopsis: intkey=P3 data=r[P2]
**
** This works exactly like OP_Insert except that the key is the
** integer value P3, not the value of the integer stored in register P3.
*/
case OP_Insert: 
case OP_InsertInt: {
  Mem *pData;       /* MEM cell holding data for the record to be inserted */

case OP_ResetCount: {
  sqlite3VdbeSetChanges(db, p->nChange);
  p->nChange = 0;
  break;
}

/* Opcode: SorterCompare P1 P2 P3 P4
** Synopsis: if key(P1)!=trim(r[P3],P4) goto P2
**
** P1 is a sorter cursor. This instruction compares a prefix of the
** record blob in register P3 against a prefix of the entry that 
** the sorter cursor currently points to.  Only the first P4 fields
** of r[P3] and the sorter record are compared.
**
** If either P3 or the sorter contains a NULL in one of their significant

  }
  assert( pC->deferredMoveto==0 );
  pC->cacheStatus = CACHE_STALE;
  break;
}

/* Opcode: Seek P1 * P3 P4 *
** Synopsis: Move P3 to P1.rowid
**
** P1 is an open index cursor and P3 is a cursor on the corresponding
** table.  This opcode does a deferred seek of the P3 table cursor
** to the row that corresponds to the current row of P1.
**
** This is a deferred seek.  Nothing actually happens until
** the cursor is used to read a record.  That way, if no reads

  UPDATE_MAX_BLOBSIZE(pIn1);
  sqlite3VdbeChangeEncoding(pIn1, encoding);
  break;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

/* Opcode: RowSetAdd P1 P2 * * *
** Synopsis: rowset(P1)=r[P2]
**
** Insert the integer value held by register P2 into a boolean index
** held in register P1.
**
** An assertion fails if P2 is not an integer.
*/
case OP_RowSetAdd: {       /* in1, in2 */
  pIn1 = &aMem[pOp->p1];
  pIn2 = &aMem[pOp->p2];
  assert( (pIn2->flags & MEM_Int)!=0 );
  if( (pIn1->flags & MEM_RowSet)==0 ){
    sqlite3VdbeMemSetRowSet(pIn1);
    if( (pIn1->flags & MEM_RowSet)==0 ) goto no_mem;
  }
  sqlite3RowSetInsert(pIn1->u.pRowSet, pIn2->u.i);
  break;
}

/* Opcode: RowSetRead P1 P2 P3 * *
** Synopsis: r[P3]=rowset(P1)
**
** Extract the smallest value from boolean index P1 and put that value into
** register P3.  Or, if boolean index P1 is initially empty, leave P3
** unchanged and jump to instruction P2.
*/
case OP_RowSetRead: {       /* jump, in1, out3 */
  i64 val;

  pOut->u.i = sqlite3BtreeMaxPageCount(pBt, newMax);
  break;
}
#endif


/* Opcode: Init * P2 * P4 *
** Synopsis: Start at P2
**
** Programs contain a single instance of this opcode as the very first
** opcode.
**
** If tracing is enabled (by the sqlite3_trace()) interface, then
** the UTF-8 string contained in P4 is emitted on the trace callback.
** Or if P4 is blank, use the string returned by sqlite3_sql().

  char *zTemp,       /* Write result here */
  int nTemp          /* Space available in zTemp[] */
){
  const char *zOpName;
  const char *zSynopsis;
  int nOpName;
  int ii, jj;
  char zAlt[50];
  zOpName = sqlite3OpcodeName(pOp->opcode);
  nOpName = sqlite3Strlen30(zOpName);
  if( zOpName[nOpName+1] ){
    int seenCom = 0;
    char c;
    zSynopsis = zOpName += nOpName + 1;
    if( strncmp(zSynopsis,"IF ",3)==0 ){
      if( pOp->p5 & SQLITE_STOREP2 ){
        sqlite3_snprintf(sizeof(zAlt), zAlt, "r[P2] = (%s)", zSynopsis+3);
      }else{
        sqlite3_snprintf(sizeof(zAlt), zAlt, "if %s goto P2", zSynopsis+3);
      }
      zSynopsis = zAlt;
    }
    for(ii=jj=0; jj<nTemp-1 && (c = zSynopsis[ii])!=0; ii++){
      if( c=='P' ){
        c = zSynopsis[++ii];
        if( c=='4' ){
          sqlite3_snprintf(nTemp-jj, zTemp+jj, "%s", zP4);
        }else if( c=='X' ){
          sqlite3_snprintf(nTemp-jj, zTemp+jj, "%s", pOp->zComment);