Move bundled copy of sqlite one level deeper to better separate it...

third_party/sqlite/src/vdbe.c

-/*
-** 2001 September 15
-**
-** 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.
-**
-*************************************************************************
-** The code in this file implements execution method of the 
-** Virtual Database Engine (VDBE).  A separate file ("vdbeaux.c")
-** handles housekeeping details such as creating and deleting
-** VDBE instances.  This file is solely interested in executing
-** the VDBE program.
-**
-** In the external interface, an "sqlite3_stmt*" is an opaque pointer
-** to a VDBE.
-**
-** The SQL parser generates a program which is then executed by
-** the VDBE to do the work of the SQL statement.  VDBE programs are 
-** similar in form to assembly language.  The program consists of
-** a linear sequence of operations.  Each operation has an opcode 
-** and 5 operands.  Operands P1, P2, and P3 are integers.  Operand P4 
-** is a null-terminated string.  Operand P5 is an unsigned character.
-** Few opcodes use all 5 operands.
-**
-** Computation results are stored on a set of registers numbered beginning
-** with 1 and going up to Vdbe.nMem.  Each register can store
-** either an integer, a null-terminated string, a floating point
-** number, or the SQL "NULL" value.  An implicit conversion from one
-** type to the other occurs as necessary.
-** 
-** Most of the code in this file is taken up by the sqlite3VdbeExec()
-** function which does the work of interpreting a VDBE program.
-** But other routines are also provided to help in building up
-** a program instruction by instruction.
-**
-** Various scripts scan this source file in order to generate HTML
-** documentation, headers files, or other derived files.  The formatting
-** of the code in this file is, therefore, important.  See other comments
-** in this file for details.  If in doubt, do not deviate from existing
-** commenting and indentation practices when changing or adding code.
-**
-** $Id: vdbe.c,v 1.874 2009/07/24 17:58:53 danielk1977 Exp $
-*/
-#include "sqliteInt.h"
-#include "vdbeInt.h"
-
-/*
-** The following global variable is incremented every time a cursor
-** moves, either by the OP_SeekXX, OP_Next, or OP_Prev opcodes.  The test
-** procedures use this information to make sure that indices are
-** working correctly.  This variable has no function other than to
-** help verify the correct operation of the library.
-*/
-#ifdef SQLITE_TEST
-int sqlite3_search_count = 0;
-#endif
-
-/*
-** When this global variable is positive, it gets decremented once before
-** each instruction in the VDBE.  When reaches zero, the u1.isInterrupted
-** field of the sqlite3 structure is set in order to simulate and interrupt.
-**
-** This facility is used for testing purposes only.  It does not function
-** in an ordinary build.
-*/
-#ifdef SQLITE_TEST
-int sqlite3_interrupt_count = 0;
-#endif
-
-/*
-** The next global variable is incremented each type the OP_Sort opcode
-** is executed.  The test procedures use this information to make sure that
-** sorting is occurring or not occurring at appropriate times.   This variable
-** has no function other than to help verify the correct operation of the
-** library.
-*/
-#ifdef SQLITE_TEST
-int sqlite3_sort_count = 0;
-#endif
-
-/*
-** The next global variable records the size of the largest MEM_Blob
-** or MEM_Str that has been used by a VDBE opcode.  The test procedures
-** use this information to make sure that the zero-blob functionality
-** is working correctly.   This variable has no function other than to
-** help verify the correct operation of the library.
-*/
-#ifdef SQLITE_TEST
-int sqlite3_max_blobsize = 0;
-static void updateMaxBlobsize(Mem *p){
-  if( (p->flags & (MEM_Str|MEM_Blob))!=0 && p->n>sqlite3_max_blobsize ){
-    sqlite3_max_blobsize = p->n;
-  }
-}
-#endif
-
-/*
-** Test a register to see if it exceeds the current maximum blob size.
-** If it does, record the new maximum blob size.
-*/
-#if defined(SQLITE_TEST) && !defined(SQLITE_OMIT_BUILTIN_TEST)
-# define UPDATE_MAX_BLOBSIZE(P)  updateMaxBlobsize(P)
-#else
-# define UPDATE_MAX_BLOBSIZE(P)
-#endif
-
-/*
-** Convert the given register into a string if it isn't one
-** already. Return non-zero if a malloc() fails.
-*/
-#define Stringify(P, enc) \
-   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc)) \
-     { goto no_mem; }
-
-/*
-** An ephemeral string value (signified by the MEM_Ephem flag) contains
-** a pointer to a dynamically allocated string where some other entity
-** is responsible for deallocating that string.  Because the register
-** does not control the string, it might be deleted without the register
-** knowing it.
-**
-** This routine converts an ephemeral string into a dynamically allocated
-** string that the register itself controls.  In other words, it
-** converts an MEM_Ephem string into an MEM_Dyn string.
-*/
-#define Deephemeralize(P) \
-   if( ((P)->flags&MEM_Ephem)!=0 \
-       && sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}
-
-/*
-** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
-** P if required.
-*/
-#define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
-
-/*
-** Argument pMem points at a register that will be passed to a
-** user-defined function or returned to the user as the result of a query.
-** The second argument, 'db_enc' is the text encoding used by the vdbe for
-** register variables.  This routine sets the pMem->enc and pMem->type
-** variables used by the sqlite3_value_*() routines.
-*/
-#define storeTypeInfo(A,B) _storeTypeInfo(A)
-static void _storeTypeInfo(Mem *pMem){
-  int flags = pMem->flags;
-  if( flags & MEM_Null ){
-    pMem->type = SQLITE_NULL;
-  }
-  else if( flags & MEM_Int ){
-    pMem->type = SQLITE_INTEGER;
-  }
-  else if( flags & MEM_Real ){
-    pMem->type = SQLITE_FLOAT;
-  }
-  else if( flags & MEM_Str ){
-    pMem->type = SQLITE_TEXT;
-  }else{
-    pMem->type = SQLITE_BLOB;
-  }
-}
-
-/*
-** Properties of opcodes.  The OPFLG_INITIALIZER macro is
-** created by mkopcodeh.awk during compilation.  Data is obtained
-** from the comments following the "case OP_xxxx:" statements in
-** this file.  
-*/
-static const unsigned char opcodeProperty[] = OPFLG_INITIALIZER;
-
-/*
-** Return true if an opcode has any of the OPFLG_xxx properties
-** specified by mask.
-*/
-int sqlite3VdbeOpcodeHasProperty(int opcode, int mask){
-  assert( opcode>0 && opcode<(int)sizeof(opcodeProperty) );
-  return (opcodeProperty[opcode]&mask)!=0;
-}
-
-/*
-** Allocate VdbeCursor number iCur.  Return a pointer to it.  Return NULL
-** if we run out of memory.
-*/
-static VdbeCursor *allocateCursor(
-  Vdbe *p,              /* The virtual machine */
-  int iCur,             /* Index of the new VdbeCursor */
-  int nField,           /* Number of fields in the table or index */
-  int iDb,              /* When database the cursor belongs to, or -1 */
-  int isBtreeCursor     /* True for B-Tree.  False for pseudo-table or vtab */
-){
-  /* Find the memory cell that will be used to store the blob of memory
-  ** required for this VdbeCursor structure. It is convenient to use a 
-  ** vdbe memory cell to manage the memory allocation required for a
-  ** VdbeCursor structure for the following reasons:
-  **
-  **   * Sometimes cursor numbers are used for a couple of different
-  **     purposes in a vdbe program. The different uses might require
-  **     different sized allocations. Memory cells provide growable
-  **     allocations.
-  **
-  **   * When using ENABLE_MEMORY_MANAGEMENT, memory cell buffers can
-  **     be freed lazily via the sqlite3_release_memory() API. This
-  **     minimizes the number of malloc calls made by the system.
-  **
-  ** Memory cells for cursors are allocated at the top of the address
-  ** space. Memory cell (p->nMem) corresponds to cursor 0. Space for
-  ** cursor 1 is managed by memory cell (p->nMem-1), etc.
-  */
-  Mem *pMem = &p->aMem[p->nMem-iCur];
-
-  int nByte;
-  VdbeCursor *pCx = 0;
-  nByte = 
-      sizeof(VdbeCursor) + 
-      (isBtreeCursor?sqlite3BtreeCursorSize():0) + 
-      2*nField*sizeof(u32);
-
-  assert( iCur<p->nCursor );
-  if( p->apCsr[iCur] ){
-    sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
-    p->apCsr[iCur] = 0;
-  }
-  if( SQLITE_OK==sqlite3VdbeMemGrow(pMem, nByte, 0) ){
-    p->apCsr[iCur] = pCx = (VdbeCursor*)pMem->z;
-    memset(pMem->z, 0, nByte);
-    pCx->iDb = iDb;
-    pCx->nField = nField;
-    if( nField ){
-      pCx->aType = (u32 *)&pMem->z[sizeof(VdbeCursor)];
-    }
-    if( isBtreeCursor ){
-      pCx->pCursor = (BtCursor*)
-          &pMem->z[sizeof(VdbeCursor)+2*nField*sizeof(u32)];
-    }
-  }
-  return pCx;
-}
-
-/*
-** Try to convert a value into a numeric representation if we can
-** do so without loss of information.  In other words, if the string
-** looks like a number, convert it into a number.  If it does not
-** look like a number, leave it alone.
-*/
-static void applyNumericAffinity(Mem *pRec){
-  if( (pRec->flags & (MEM_Real|MEM_Int))==0 ){
-    int realnum;
-    sqlite3VdbeMemNulTerminate(pRec);
-    if( (pRec->flags&MEM_Str)
-         && sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
-      i64 value;
-      sqlite3VdbeChangeEncoding(pRec, SQLITE_UTF8);
-      if( !realnum && sqlite3Atoi64(pRec->z, &value) ){
-        pRec->u.i = value;
-        MemSetTypeFlag(pRec, MEM_Int);
-      }else{
-        sqlite3VdbeMemRealify(pRec);
-      }
-    }
-  }
-}
-
-/*
-** Processing is determine by the affinity parameter:
-**
-** SQLITE_AFF_INTEGER:
-** SQLITE_AFF_REAL:
-** SQLITE_AFF_NUMERIC:
-**    Try to convert pRec to an integer representation or a 
-**    floating-point representation if an integer representation
-**    is not possible.  Note that the integer representation is
-**    always preferred, even if the affinity is REAL, because
-**    an integer representation is more space efficient on disk.
-**
-** SQLITE_AFF_TEXT:
-**    Convert pRec to a text representation.
-**
-** SQLITE_AFF_NONE:
-**    No-op.  pRec is unchanged.
-*/
-static void applyAffinity(
-  Mem *pRec,          /* The value to apply affinity to */
-  char affinity,      /* The affinity to be applied */
-  u8 enc              /* Use this text encoding */
-){
-  if( affinity==SQLITE_AFF_TEXT ){
-    /* 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.
-    */
-    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
-      sqlite3VdbeMemStringify(pRec, enc);
-    }
-    pRec->flags &= ~(MEM_Real|MEM_Int);
-  }else if( affinity!=SQLITE_AFF_NONE ){
-    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
-             || affinity==SQLITE_AFF_NUMERIC );
-    applyNumericAffinity(pRec);
-    if( pRec->flags & MEM_Real ){
-      sqlite3VdbeIntegerAffinity(pRec);
-    }
-  }
-}
-
-/*
-** Try to convert the type of a function argument or a result column
-** into a numeric representation.  Use either INTEGER or REAL whichever
-** is appropriate.  But only do the conversion if it is possible without
-** loss of information and return the revised type of the argument.
-**
-** This is an EXPERIMENTAL api and is subject to change or removal.
-*/
-int sqlite3_value_numeric_type(sqlite3_value *pVal){
-  Mem *pMem = (Mem*)pVal;
-  applyNumericAffinity(pMem);
-  storeTypeInfo(pMem, 0);
-  return pMem->type;
-}
-
-/*
-** Exported version of applyAffinity(). This one works on sqlite3_value*, 
-** not the internal Mem* type.
-*/
-void sqlite3ValueApplyAffinity(
-  sqlite3_value *pVal, 
-  u8 affinity, 
-  u8 enc
-){
-  applyAffinity((Mem *)pVal, affinity, enc);
-}
-
-#ifdef SQLITE_DEBUG
-/*
-** Write a nice string representation of the contents of cell pMem
-** into buffer zBuf, length nBuf.
-*/
-void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf){
-  char *zCsr = zBuf;
-  int f = pMem->flags;
-
-  static const char *const encnames[] = {"(X)", "(8)", "(16LE)", "(16BE)"};
-
-  if( f&MEM_Blob ){
-    int i;
-    char c;
-    if( f & MEM_Dyn ){
-      c = 'z';
-      assert( (f & (MEM_Static|MEM_Ephem))==0 );
-    }else if( f & MEM_Static ){
-      c = 't';
-      assert( (f & (MEM_Dyn|MEM_Ephem))==0 );
-    }else if( f & MEM_Ephem ){
-      c = 'e';
-      assert( (f & (MEM_Static|MEM_Dyn))==0 );
-    }else{
-      c = 's';
-    }
-
-    sqlite3_snprintf(100, zCsr, "%c", c);
-    zCsr += sqlite3Strlen30(zCsr);
-    sqlite3_snprintf(100, zCsr, "%d[", pMem->n);
-    zCsr += sqlite3Strlen30(zCsr);
-    for(i=0; i<16 && i<pMem->n; i++){
-      sqlite3_snprintf(100, zCsr, "%02X", ((int)pMem->z[i] & 0xFF));
-      zCsr += sqlite3Strlen30(zCsr);
-    }
-    for(i=0; i<16 && i<pMem->n; i++){
-      char z = pMem->z[i];
-      if( z<32 || z>126 ) *zCsr++ = '.';
-      else *zCsr++ = z;
-    }
-
-    sqlite3_snprintf(100, zCsr, "]%s", encnames[pMem->enc]);
-    zCsr += sqlite3Strlen30(zCsr);
-    if( f & MEM_Zero ){
-      sqlite3_snprintf(100, zCsr,"+%dz",pMem->u.nZero);
-      zCsr += sqlite3Strlen30(zCsr);
-    }
-    *zCsr = '\0';
-  }else if( f & MEM_Str ){
-    int j, k;
-    zBuf[0] = ' ';
-    if( f & MEM_Dyn ){
-      zBuf[1] = 'z';
-      assert( (f & (MEM_Static|MEM_Ephem))==0 );
-    }else if( f & MEM_Static ){
-      zBuf[1] = 't';
-      assert( (f & (MEM_Dyn|MEM_Ephem))==0 );
-    }else if( f & MEM_Ephem ){
-      zBuf[1] = 'e';
-      assert( (f & (MEM_Static|MEM_Dyn))==0 );
-    }else{
-      zBuf[1] = 's';
-    }
-    k = 2;
-    sqlite3_snprintf(100, &zBuf[k], "%d", pMem->n);
-    k += sqlite3Strlen30(&zBuf[k]);
-    zBuf[k++] = '[';
-    for(j=0; j<15 && j<pMem->n; j++){
-      u8 c = pMem->z[j];
-      if( c>=0x20 && c<0x7f ){
-        zBuf[k++] = c;
-      }else{
-        zBuf[k++] = '.';
-      }
-    }
-    zBuf[k++] = ']';
-    sqlite3_snprintf(100,&zBuf[k], encnames[pMem->enc]);
-    k += sqlite3Strlen30(&zBuf[k]);
-    zBuf[k++] = 0;
-  }
-}
-#endif
-
-#ifdef SQLITE_DEBUG
-/*
-** Print the value of a register for tracing purposes:
-*/
-static void memTracePrint(FILE *out, Mem *p){
-  if( p->flags & MEM_Null ){
-    fprintf(out, " NULL");
-  }else if( (p->flags & (MEM_Int|MEM_Str))==(MEM_Int|MEM_Str) ){
-    fprintf(out, " si:%lld", p->u.i);
-  }else if( p->flags & MEM_Int ){
-    fprintf(out, " i:%lld", p->u.i);
-#ifndef SQLITE_OMIT_FLOATING_POINT
-  }else if( p->flags & MEM_Real ){
-    fprintf(out, " r:%g", p->r);
-#endif
-  }else if( p->flags & MEM_RowSet ){
-    fprintf(out, " (rowset)");
-  }else{
-    char zBuf[200];
-    sqlite3VdbeMemPrettyPrint(p, zBuf);
-    fprintf(out, " ");
-    fprintf(out, "%s", zBuf);
-  }
-}
-static void registerTrace(FILE *out, int iReg, Mem *p){
-  fprintf(out, "REG[%d] = ", iReg);
-  memTracePrint(out, p);
-  fprintf(out, "\n");
-}
-#endif
-
-#ifdef SQLITE_DEBUG
-#  define REGISTER_TRACE(R,M) if(p->trace)registerTrace(p->trace,R,M)
-#else
-#  define REGISTER_TRACE(R,M)
-#endif
-
-
-#ifdef VDBE_PROFILE
-
-/* 
-** hwtime.h contains inline assembler code for implementing 
-** high-performance timing routines.
-*/
-#include "hwtime.h"
-
-#endif
-
-/*
-** The CHECK_FOR_INTERRUPT macro defined here looks to see if the
-** sqlite3_interrupt() routine has been called.  If it has been, then
-** processing of the VDBE program is interrupted.
-**
-** This macro added to every instruction that does a jump in order to
-** implement a loop.  This test used to be on every single instruction,
-** but that meant we more testing that we needed.  By only testing the
-** flag on jump instructions, we get a (small) speed improvement.
-*/
-#define CHECK_FOR_INTERRUPT \
-   if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
-
-#ifdef SQLITE_DEBUG
-static int fileExists(sqlite3 *db, const char *zFile){
-  int res = 0;
-  int rc = SQLITE_OK;
-#ifdef SQLITE_TEST
-  /* If we are currently testing IO errors, then do not call OsAccess() to
-  ** test for the presence of zFile. This is because any IO error that
-  ** occurs here will not be reported, causing the test to fail.
-  */
-  extern int sqlite3_io_error_pending;
-  if( sqlite3_io_error_pending<=0 )
-#endif
-    rc = sqlite3OsAccess(db->pVfs, zFile, SQLITE_ACCESS_EXISTS, &res);
-  return (res && rc==SQLITE_OK);
-}
-#endif
-
-#ifndef NDEBUG
-/*
-** This function is only called from within an assert() expression. It
-** checks that the sqlite3.nTransaction variable is correctly set to
-** the number of non-transaction savepoints currently in the 
-** linked list starting at sqlite3.pSavepoint.
-** 
-** Usage:
-**
-**     assert( checkSavepointCount(db) );
-*/
-static int checkSavepointCount(sqlite3 *db){
-  int n = 0;
-  Savepoint *p;
-  for(p=db->pSavepoint; p; p=p->pNext) n++;
-  assert( n==(db->nSavepoint + db->isTransactionSavepoint) );
-  return 1;
-}
-#endif
-
-/*
-** Execute as much of a VDBE program as we can then return.
-**
-** sqlite3VdbeMakeReady() must be called before this routine in order to
-** close the program with a final OP_Halt and to set up the callbacks
-** and the error message pointer.
-**
-** Whenever a row or result data is available, this routine will either
-** invoke the result callback (if there is one) or return with
-** SQLITE_ROW.
-**
-** If an attempt is made to open a locked database, then this routine
-** will either invoke the busy callback (if there is one) or it will
-** return SQLITE_BUSY.
-**
-** If an error occurs, an error message is written to memory obtained
-** from sqlite3_malloc() and p->zErrMsg is made to point to that memory.
-** The error code is stored in p->rc and this routine returns SQLITE_ERROR.
-**
-** If the callback ever returns non-zero, then the program exits
-** immediately.  There will be no error message but the p->rc field is
-** set to SQLITE_ABORT and this routine will return SQLITE_ERROR.
-**
-** A memory allocation error causes p->rc to be set to SQLITE_NOMEM and this
-** routine to return SQLITE_ERROR.
-**
-** Other fatal errors return SQLITE_ERROR.
-**
-** After this routine has finished, sqlite3VdbeFinalize() should be
-** used to clean up the mess that was left behind.
-*/
-int sqlite3VdbeExec(
-  Vdbe *p                    /* The VDBE */
-){
-  int pc;                    /* The program counter */
-  Op *pOp;                   /* Current operation */
-  int rc = SQLITE_OK;        /* Value to return */
-  sqlite3 *db = p->db;       /* The database */
-  u8 encoding = ENC(db);     /* The database encoding */
-  Mem *pIn1 = 0;             /* 1st input operand */
-  Mem *pIn2 = 0;             /* 2nd input operand */
-  Mem *pIn3 = 0;             /* 3rd input operand */
-  Mem *pOut = 0;             /* Output operand */
-  u8 opProperty;
-  int iCompare = 0;          /* Result of last OP_Compare operation */
-  int *aPermute = 0;         /* Permutation of columns for OP_Compare */
-#ifdef VDBE_PROFILE
-  u64 start;                 /* CPU clock count at start of opcode */
-  int origPc;                /* Program counter at start of opcode */
-#endif
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-  int nProgressOps = 0;      /* Opcodes executed since progress callback. */
-#endif
-  /*** INSERT STACK UNION HERE ***/
-
-  assert( p->magic==VDBE_MAGIC_RUN );  /* sqlite3_step() verifies this */
-  assert( db->magic==SQLITE_MAGIC_BUSY );
-  sqlite3VdbeMutexArrayEnter(p);
-  if( p->rc==SQLITE_NOMEM ){
-    /* This happens if a malloc() inside a call to sqlite3_column_text() or
-    ** sqlite3_column_text16() failed.  */
-    goto no_mem;
-  }
-  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
-  p->rc = SQLITE_OK;
-  assert( p->explain==0 );
-  p->pResultSet = 0;
-  db->busyHandler.nBusy = 0;
-  CHECK_FOR_INTERRUPT;
-  sqlite3VdbeIOTraceSql(p);
-#ifdef SQLITE_DEBUG
-  sqlite3BeginBenignMalloc();
-  if( p->pc==0 
-   && ((p->db->flags & SQLITE_VdbeListing) || fileExists(db, "vdbe_explain"))
-  ){
-    int i;
-    printf("VDBE Program Listing:\n");
-    sqlite3VdbePrintSql(p);
-    for(i=0; i<p->nOp; i++){
-      sqlite3VdbePrintOp(stdout, i, &p->aOp[i]);
-    }
-  }
-  if( fileExists(db, "vdbe_trace") ){
-    p->trace = stdout;
-  }
-  sqlite3EndBenignMalloc();
-#endif
-  for(pc=p->pc; rc==SQLITE_OK; pc++){
-    assert( pc>=0 && pc<p->nOp );
-    if( db->mallocFailed ) goto no_mem;
-#ifdef VDBE_PROFILE
-    origPc = pc;
-    start = sqlite3Hwtime();
-#endif
-    pOp = &p->aOp[pc];
-
-    /* Only allow tracing if SQLITE_DEBUG is defined.
-    */
-#ifdef SQLITE_DEBUG
-    if( p->trace ){
-      if( pc==0 ){
-        printf("VDBE Execution Trace:\n");
-        sqlite3VdbePrintSql(p);
-      }
-      sqlite3VdbePrintOp(p->trace, pc, pOp);
-    }
-    if( p->trace==0 && pc==0 ){
-      sqlite3BeginBenignMalloc();
-      if( fileExists(db, "vdbe_sqltrace") ){
-        sqlite3VdbePrintSql(p);
-      }
-      sqlite3EndBenignMalloc();
-    }
-#endif
-      
-
-    /* Check to see if we need to simulate an interrupt.  This only happens
-    ** if we have a special test build.
-    */
-#ifdef SQLITE_TEST
-    if( sqlite3_interrupt_count>0 ){
-      sqlite3_interrupt_count--;
-      if( sqlite3_interrupt_count==0 ){
-        sqlite3_interrupt(db);
-      }
-    }
-#endif
-
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-    /* Call the progress callback if it is configured and the required number
-    ** of VDBE ops have been executed (either since this invocation of
-    ** sqlite3VdbeExec() or since last time the progress callback was called).
-    ** If the progress callback returns non-zero, exit the virtual machine with
-    ** a return code SQLITE_ABORT.
-    */
-    if( db->xProgress ){
-      if( db->nProgressOps==nProgressOps ){
-        int prc;
-        if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-        prc =db->xProgress(db->pProgressArg);
-        if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-        if( prc!=0 ){
-          rc = SQLITE_INTERRUPT;
-          goto vdbe_error_halt;
-        }
-        nProgressOps = 0;
-      }
-      nProgressOps++;
-    }
-#endif
-
-    /* Do common setup processing for any opcode that is marked
-    ** with the "out2-prerelease" tag.  Such opcodes have a single
-    ** output which is specified by the P2 parameter.  The P2 register
-    ** is initialized to a NULL.
-    */
-    opProperty = opcodeProperty[pOp->opcode];
-    if( (opProperty & OPFLG_OUT2_PRERELEASE)!=0 ){
-      assert( pOp->p2>0 );
-      assert( pOp->p2<=p->nMem );
-      pOut = &p->aMem[pOp->p2];
-      sqlite3VdbeMemReleaseExternal(pOut);
-      pOut->flags = MEM_Null;
-      pOut->n = 0;
-    }else
- 
-    /* Do common setup for opcodes marked with one of the following
-    ** combinations of properties.
-    **
-    **           in1
-    **           in1 in2
-    **           in1 in2 out3
-    **           in1 in3
-    **
-    ** Variables pIn1, pIn2, and pIn3 are made to point to appropriate
-    ** registers for inputs.  Variable pOut points to the output register.
-    */
-    if( (opProperty & OPFLG_IN1)!=0 ){
-      assert( pOp->p1>0 );
-      assert( pOp->p1<=p->nMem );
-      pIn1 = &p->aMem[pOp->p1];
-      REGISTER_TRACE(pOp->p1, pIn1);
-      if( (opProperty & OPFLG_IN2)!=0 ){
-        assert( pOp->p2>0 );
-        assert( pOp->p2<=p->nMem );
-        pIn2 = &p->aMem[pOp->p2];
-        REGISTER_TRACE(pOp->p2, pIn2);
-        /* As currently implemented, in2 implies out3.  There is no reason
-        ** why this has to be, it just worked out that way. */
-        assert( (opProperty & OPFLG_OUT3)!=0 );
-        assert( pOp->p3>0 );
-        assert( pOp->p3<=p->nMem );
-        pOut = &p->aMem[pOp->p3];
-      }else if( (opProperty & OPFLG_IN3)!=0 ){
-        assert( pOp->p3>0 );
-        assert( pOp->p3<=p->nMem );
-        pIn3 = &p->aMem[pOp->p3];
-        REGISTER_TRACE(pOp->p3, pIn3);
-      }
-    }else if( (opProperty & OPFLG_IN2)!=0 ){
-      assert( pOp->p2>0 );
-      assert( pOp->p2<=p->nMem );
-      pIn2 = &p->aMem[pOp->p2];
-      REGISTER_TRACE(pOp->p2, pIn2);
-    }else if( (opProperty & OPFLG_IN3)!=0 ){
-      assert( pOp->p3>0 );
-      assert( pOp->p3<=p->nMem );
-      pIn3 = &p->aMem[pOp->p3];
-      REGISTER_TRACE(pOp->p3, pIn3);
-    }
-
-    switch( pOp->opcode ){
-
-/*****************************************************************************
-** What follows is a massive switch statement where each case implements a
-** separate instruction in the virtual machine.  If we follow the usual
-** indentation conventions, each case should be indented by 6 spaces.  But
-** that is a lot of wasted space on the left margin.  So the code within
-** the switch statement will break with convention and be flush-left. Another
-** big comment (similar to this one) will mark the point in the code where
-** we transition back to normal indentation.
-**
-** The formatting of each case is important.  The makefile for SQLite
-** generates two C files "opcodes.h" and "opcodes.c" by scanning this
-** file looking for lines that begin with "case OP_".  The opcodes.h files
-** will be filled with #defines that give unique integer values to each
-** opcode and the opcodes.c file is filled with an array of strings where
-** each string is the symbolic name for the corresponding opcode.  If the
-** case statement is followed by a comment of the form "/# same as ... #/"
-** that comment is used to determine the particular value of the opcode.
-**
-** Other keywords in the comment that follows each case are used to
-** construct the OPFLG_INITIALIZER value that initializes opcodeProperty[].
-** Keywords include: in1, in2, in3, out2_prerelease, out2, out3.  See
-** the mkopcodeh.awk script for additional information.
-**
-** Documentation about VDBE opcodes is generated by scanning this file
-** for lines of that contain "Opcode:".  That line and all subsequent
-** comment lines are used in the generation of the opcode.html documentation
-** file.
-**
-** SUMMARY:
-**
-**     Formatting is important to scripts that scan this file.
-**     Do not deviate from the formatting style currently in use.
-**
-*****************************************************************************/
-
-/* Opcode:  Goto * P2 * * *
-**
-** An unconditional jump to address P2.
-** The next instruction executed will be 
-** the one at index P2 from the beginning of
-** the program.
-*/
-case OP_Goto: {             /* jump */
-  CHECK_FOR_INTERRUPT;
-  pc = pOp->p2 - 1;
-  break;
-}
-
-/* Opcode:  Gosub P1 P2 * * *
-**
-** Write the current address onto register P1
-** and then jump to address P2.
-*/
-case OP_Gosub: {            /* jump */
-  assert( pOp->p1>0 );
-  assert( pOp->p1<=p->nMem );
-  pIn1 = &p->aMem[pOp->p1];
-  assert( (pIn1->flags & MEM_Dyn)==0 );
-  pIn1->flags = MEM_Int;
-  pIn1->u.i = pc;
-  REGISTER_TRACE(pOp->p1, pIn1);
-  pc = pOp->p2 - 1;
-  break;
-}
-
-/* Opcode:  Return P1 * * * *
-**
-** Jump to the next instruction after the address in register P1.
-*/
-case OP_Return: {           /* in1 */
-  assert( pIn1->flags & MEM_Int );
-  pc = (int)pIn1->u.i;
-  break;
-}
-
-/* Opcode:  Yield P1 * * * *
-**
-** Swap the program counter with the value in register P1.
-*/
-case OP_Yield: {            /* in1 */
-  int pcDest;
-  assert( (pIn1->flags & MEM_Dyn)==0 );
-  pIn1->flags = MEM_Int;
-  pcDest = (int)pIn1->u.i;
-  pIn1->u.i = pc;
-  REGISTER_TRACE(pOp->p1, pIn1);
-  pc = pcDest;
-  break;
-}
-
-/* Opcode:  HaltIfNull  P1 P2 P3 P4 *
-**
-** Check the value in register P3.  If is 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.
-*/
-case OP_HaltIfNull: {      /* in3 */
-  if( (pIn3->flags & MEM_Null)==0 ) break;
-  /* Fall through into OP_Halt */
-}
-
-/* Opcode:  Halt P1 P2 * P4 *
-**
-** Exit immediately.  All open cursors, etc are closed
-** automatically.
-**
-** P1 is the result code returned by sqlite3_exec(), sqlite3_reset(),
-** or sqlite3_finalize().  For a normal halt, this should be SQLITE_OK (0).
-** For errors, it can be some other value.  If P1!=0 then P2 will determine
-** whether or not to rollback the current transaction.  Do not rollback
-** if P2==OE_Fail. Do the rollback if P2==OE_Rollback.  If P2==OE_Abort,
-** then back out all changes that have occurred during this execution of the
-** VDBE, but do not rollback the transaction. 
-**
-** If P4 is not null then it is an error message string.
-**
-** There is an implied "Halt 0 0 0" instruction inserted at the very end of
-** every program.  So a jump past the last instruction of the program
-** is the same as executing Halt.
-*/
-case OP_Halt: {
-  if( pOp->p1==SQLITE_OK && p->pFrame ){
-    /* Halt the sub-program. Return control to the parent frame. */
-    VdbeFrame *pFrame = p->pFrame;
-    p->pFrame = pFrame->pParent;
-    p->nFrame--;
-    sqlite3VdbeSetChanges(db, p->nChange);
-    pc = sqlite3VdbeFrameRestore(pFrame);
-    if( pOp->p2==OE_Ignore ){
-      /* Instruction pc is the OP_Program that invoked the sub-program 
-      ** currently being halted. If the p2 instruction of this OP_Halt
-      ** instruction is set to OE_Ignore, then the sub-program is throwing
-      ** an IGNORE exception. In this case jump to the address specified
-      ** as the p2 of the calling OP_Program.  */
-      pc = p->aOp[pc].p2-1;
-    }
-    break;
-  }
-
-  p->rc = pOp->p1;
-  p->errorAction = (u8)pOp->p2;
-  p->pc = pc;
-  if( pOp->p4.z ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", pOp->p4.z);
-  }
-  rc = sqlite3VdbeHalt(p);
-  assert( rc==SQLITE_BUSY || rc==SQLITE_OK );
-  if( rc==SQLITE_BUSY ){
-    p->rc = rc = SQLITE_BUSY;
-  }else{
-    rc = p->rc ? SQLITE_ERROR : SQLITE_DONE;
-  }
-  goto vdbe_return;
-}
-
-/* Opcode: Integer P1 P2 * * *
-**
-** The 32-bit integer value P1 is written into register P2.
-*/
-case OP_Integer: {         /* out2-prerelease */
-  pOut->flags = MEM_Int;
-  pOut->u.i = pOp->p1;
-  break;
-}
-
-/* Opcode: Int64 * P2 * P4 *
-**
-** P4 is a pointer to a 64-bit integer value.
-** Write that value into register P2.
-*/
-case OP_Int64: {           /* out2-prerelease */
-  assert( pOp->p4.pI64!=0 );
-  pOut->flags = MEM_Int;
-  pOut->u.i = *pOp->p4.pI64;
-  break;
-}
-
-/* Opcode: Real * P2 * P4 *
-**
-** 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->r = *pOp->p4.pReal;
-  break;
-}
-
-/* Opcode: String8 * P2 * P4 *
-**
-** P4 points to a nul terminated UTF-8 string. This opcode is transformed 
-** into an OP_String before it is executed for the first time.
-*/
-case OP_String8: {         /* same as TK_STRING, out2-prerelease */
-  assert( pOp->p4.z!=0 );
-  pOp->opcode = OP_String;
-  pOp->p1 = sqlite3Strlen30(pOp->p4.z);
-
-#ifndef SQLITE_OMIT_UTF16
-  if( encoding!=SQLITE_UTF8 ){
-    rc = sqlite3VdbeMemSetStr(pOut, pOp->p4.z, -1, SQLITE_UTF8, SQLITE_STATIC);
-    if( rc==SQLITE_TOOBIG ) goto too_big;
-    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pOut, encoding) ) goto no_mem;
-    assert( pOut->zMalloc==pOut->z );
-    assert( pOut->flags & MEM_Dyn );
-    pOut->zMalloc = 0;
-    pOut->flags |= MEM_Static;
-    pOut->flags &= ~MEM_Dyn;
-    if( pOp->p4type==P4_DYNAMIC ){
-      sqlite3DbFree(db, pOp->p4.z);
-    }
-    pOp->p4type = P4_DYNAMIC;
-    pOp->p4.z = pOut->z;
-    pOp->p1 = pOut->n;
-  }
-#endif
-  if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-    goto too_big;
-  }
-  /* Fall through to the next case, OP_String */
-}
-  
-/* Opcode: String P1 P2 * P4 *
-**
-** The string value P4 of length P1 (bytes) is stored in register P2.
-*/
-case OP_String: {          /* out2-prerelease */
-  assert( pOp->p4.z!=0 );
-  pOut->flags = MEM_Str|MEM_Static|MEM_Term;
-  pOut->z = pOp->p4.z;
-  pOut->n = pOp->p1;
-  pOut->enc = encoding;
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
-}
-
-/* Opcode: Null * P2 * * *
-**
-** Write a NULL into register P2.
-*/
-case OP_Null: {           /* out2-prerelease */
-  break;
-}
-
-
-/* Opcode: Blob P1 P2 * P4
-**
-** P4 points to a blob of data P1 bytes long.  Store this
-** blob in register P2. This instruction is not coded directly
-** by the compiler. Instead, the compiler layer specifies
-** an OP_HexBlob opcode, with the hex string representation of
-** the blob as P4. This opcode is transformed to an OP_Blob
-** the first time it is executed.
-*/
-case OP_Blob: {                /* out2-prerelease */
-  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 );
-
-  while( n-- > 0 ){
-    pVar = &p->aVar[p1++];
-    if( sqlite3VdbeMemTooBig(pVar) ){
-      goto too_big;
-    }
-    pOut = &p->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
-** left holding a NULL.  It is an error for register ranges
-** P1..P1+P3-1 and P2..P2+P3-1 to overlap.
-*/
-case OP_Move: {
-  char *zMalloc;   /* Holding variable for allocated memory */
-  int n;           /* Number of registers left to copy */
-  int p1;          /* Register to copy from */
-  int p2;          /* Register to copy to */
-
-  n = pOp->p3;
-  p1 = pOp->p1;
-  p2 = pOp->p2;
-  assert( n>0 && p1>0 && p2>0 );
-  assert( p1+n<=p2 || p2+n<=p1 );
-
-  pIn1 = &p->aMem[p1];
-  pOut = &p->aMem[p2];
-  while( n-- ){
-    assert( pOut<=&p->aMem[p->nMem] );
-    assert( pIn1<=&p->aMem[p->nMem] );
-    zMalloc = pOut->zMalloc;
-    pOut->zMalloc = 0;
-    sqlite3VdbeMemMove(pOut, pIn1);
-    pIn1->zMalloc = zMalloc;
-    REGISTER_TRACE(p2++, pOut);
-    pIn1++;
-    pOut++;
-  }
-  break;
-}
-
-/* Opcode: Copy P1 P2 * * *
-**
-** Make a copy of register P1 into register P2.
-**
-** This instruction makes a deep copy of the value.  A duplicate
-** is made of any string or blob constant.  See also OP_SCopy.
-*/
-case OP_Copy: {             /* in1 */
-  assert( pOp->p2>0 );
-  assert( pOp->p2<=p->nMem );
-  pOut = &p->aMem[pOp->p2];
-  assert( pOut!=pIn1 );
-  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
-  Deephemeralize(pOut);
-  REGISTER_TRACE(pOp->p2, pOut);
-  break;
-}
-
-/* Opcode: SCopy P1 P2 * * *
-**
-** Make a shallow copy of register P1 into register P2.
-**
-** This instruction makes a shallow copy of the value.  If the value
-** is a string or blob, then the copy is only a pointer to the
-** original and hence if the original changes so will the copy.
-** Worse, if the original is deallocated, the copy becomes invalid.
-** Thus the program must guarantee that the original will not change
-** during the lifetime of the copy.  Use OP_Copy to make a complete
-** copy.
-*/
-case OP_SCopy: {            /* in1 */
-  REGISTER_TRACE(pOp->p1, pIn1);
-  assert( pOp->p2>0 );
-  assert( pOp->p2<=p->nMem );
-  pOut = &p->aMem[pOp->p2];
-  assert( pOut!=pIn1 );
-  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
-  REGISTER_TRACE(pOp->p2, pOut);
-  break;
-}
-
-/* Opcode: ResultRow 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 top P1 values as the result
-** row.
-*/
-case OP_ResultRow: {
-  Mem *pMem;
-  int i;
-  assert( p->nResColumn==pOp->p2 );
-  assert( pOp->p1>0 );
-  assert( pOp->p1+pOp->p2<=p->nMem+1 );
-
-  /* If the SQLITE_CountRows flag is set in sqlite3.flags mask, then 
-  ** DML statements invoke this opcode to return the number of rows 
-  ** modified to the user. This is the only way that a VM that
-  ** opens a statement transaction may invoke this opcode.
-  **
-  ** In case this is such a statement, close any statement transaction
-  ** opened by this VM before returning control to the user. This is to
-  ** ensure that statement-transactions are always nested, not overlapping.
-  ** If the open statement-transaction is not closed here, then the user
-  ** may step another VM that opens its own statement transaction. This
-  ** may lead to overlapping statement transactions.
-  **
-  ** The statement transaction is never a top-level transaction.  Hence
-  ** the RELEASE call below can never fail.
-  */
-  assert( p->iStatement==0 || db->flags&SQLITE_CountRows );
-  rc = sqlite3VdbeCloseStatement(p, SAVEPOINT_RELEASE);
-  if( NEVER(rc!=SQLITE_OK) ){
-    break;
-  }
-
-  /* Invalidate all ephemeral cursor row caches */
-  p->cacheCtr = (p->cacheCtr + 2)|1;
-
-  /* Make sure the results of the current row are \000 terminated
-  ** and have an assigned type.  The results are de-ephemeralized as
-  ** as side effect.
-  */
-  pMem = p->pResultSet = &p->aMem[pOp->p1];
-  for(i=0; i<pOp->p2; i++){
-    sqlite3VdbeMemNulTerminate(&pMem[i]);
-    storeTypeInfo(&pMem[i], encoding);
-    REGISTER_TRACE(pOp->p1+i, &pMem[i]);
-  }
-  if( db->mallocFailed ) goto no_mem;
-
-  /* Return SQLITE_ROW
-  */
-  p->pc = pc + 1;
-  rc = SQLITE_ROW;
-  goto vdbe_return;
-}
-
-/* Opcode: Concat P1 P2 P3 * *
-**
-** Add the text in register P1 onto the end of the text in
-** register P2 and store the result in register P3.
-** If either the P1 or P2 text are NULL then store NULL in P3.
-**
-**   P3 = P2 || P1
-**
-** It is illegal for P1 and P3 to be the same register. Sometimes,
-** if P3 is the same register as P2, the implementation is able
-** to avoid a memcpy().
-*/
-case OP_Concat: {           /* same as TK_CONCAT, in1, in2, out3 */
-  i64 nByte;
-
-  assert( pIn1!=pOut );
-  if( (pIn1->flags | pIn2->flags) & MEM_Null ){
-    sqlite3VdbeMemSetNull(pOut);
-    break;
-  }
-  if( ExpandBlob(pIn1) || ExpandBlob(pIn2) ) goto no_mem;
-  Stringify(pIn1, encoding);
-  Stringify(pIn2, encoding);
-  nByte = pIn1->n + pIn2->n;
-  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-    goto too_big;
-  }
-  MemSetTypeFlag(pOut, MEM_Str);
-  if( sqlite3VdbeMemGrow(pOut, (int)nByte+2, pOut==pIn2) ){
-    goto no_mem;
-  }
-  if( pOut!=pIn2 ){
-    memcpy(pOut->z, pIn2->z, pIn2->n);
-  }
-  memcpy(&pOut->z[pIn2->n], pIn1->z, pIn1->n);
-  pOut->z[nByte] = 0;
-  pOut->z[nByte+1] = 0;
-  pOut->flags |= MEM_Term;
-  pOut->n = (int)nByte;
-  pOut->enc = encoding;
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
-}
-
-/* Opcode: Add P1 P2 P3 * *
-**
-** 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 * *
-**
-**
-** 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 * *
-**
-** 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 * *
-**
-** 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 * *
-**
-** Compute the remainder after integer division of the value in
-** register P1 by the value in register P2 and store the result in P3. 
-** If the value in register P2 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 */
-case OP_Subtract:              /* same as TK_MINUS, in1, in2, out3 */
-case OP_Multiply:              /* same as TK_STAR, in1, in2, out3 */
-case OP_Divide:                /* same as TK_SLASH, in1, in2, out3 */
-case OP_Remainder: {           /* same as TK_REM, in1, in2, out3 */
-  int flags;      /* Combined MEM_* flags from both inputs */
-  i64 iA;         /* Integer value of left operand */
-  i64 iB;         /* Integer value of right operand */
-  double rA;      /* Real value of left operand */
-  double rB;      /* Real value of right operand */
-
-  applyNumericAffinity(pIn1);
-  applyNumericAffinity(pIn2);
-  flags = pIn1->flags | pIn2->flags;
-  if( (flags & MEM_Null)!=0 ) goto arithmetic_result_is_null;
-  if( (pIn1->flags & pIn2->flags & MEM_Int)==MEM_Int ){
-    iA = pIn1->u.i;
-    iB = pIn2->u.i;
-    switch( pOp->opcode ){
-      case OP_Add:         iB += iA;       break;
-      case OP_Subtract:    iB -= iA;       break;
-      case OP_Multiply:    iB *= iA;       break;
-      case OP_Divide: {
-        if( iA==0 ) goto arithmetic_result_is_null;
-        /* Dividing the largest possible negative 64-bit integer (1<<63) by 
-        ** -1 returns an integer too large to store in a 64-bit data-type. On
-        ** some architectures, the value overflows to (1<<63). On others,
-        ** a SIGFPE is issued. The following statement normalizes this
-        ** behavior so that all architectures behave as if integer 
-        ** overflow occurred.
-        */
-        if( iA==-1 && iB==SMALLEST_INT64 ) iA = 1;
-        iB /= iA;
-        break;
-      }
-      default: {
-        if( iA==0 ) goto arithmetic_result_is_null;
-        if( iA==-1 ) iA = 1;
-        iB %= iA;
-        break;
-      }
-    }
-    pOut->u.i = iB;
-    MemSetTypeFlag(pOut, MEM_Int);
-  }else{
-    rA = sqlite3VdbeRealValue(pIn1);
-    rB = sqlite3VdbeRealValue(pIn2);
-    switch( pOp->opcode ){
-      case OP_Add:         rB += rA;       break;
-      case OP_Subtract:    rB -= rA;       break;
-      case OP_Multiply:    rB *= rA;       break;
-      case OP_Divide: {
-        /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
-        if( rA==(double)0 ) goto arithmetic_result_is_null;
-        rB /= rA;
-        break;
-      }
-      default: {
-        iA = (i64)rA;
-        iB = (i64)rB;
-        if( iA==0 ) goto arithmetic_result_is_null;
-        if( iA==-1 ) iA = 1;
-        rB = (double)(iB % iA);
-        break;
-      }
-    }
-    if( sqlite3IsNaN(rB) ){
-      goto arithmetic_result_is_null;
-    }
-    pOut->r = rB;
-    MemSetTypeFlag(pOut, MEM_Real);
-    if( (flags & MEM_Real)==0 ){
-      sqlite3VdbeIntegerAffinity(pOut);
-    }
-  }
-  break;
-
-arithmetic_result_is_null:
-  sqlite3VdbeMemSetNull(pOut);
-  break;
-}
-
-/* Opcode: CollSeq * * P4
-**
-** P4 is a pointer to a CollSeq struct. If the next call to a user function
-** or aggregate calls sqlite3GetFuncCollSeq(), this collation sequence will
-** be returned. This is used by the built-in min(), max() and nullif()
-** functions.
-**
-** The interface used by the implementation of the aforementioned functions
-** to retrieve the collation sequence set by this opcode is not available
-** publicly, only to user functions defined in func.c.
-*/
-case OP_CollSeq: {
-  assert( pOp->p4type==P4_COLLSEQ );
-  break;
-}
-
-/* Opcode: Function P1 P2 P3 P4 P5
-**
-** Invoke a user function (P4 is a pointer to a Function structure that
-** defines the function) with P5 arguments taken from register P2 and
-** successors.  The result of the function is stored in register P3.
-** Register P3 must not be one of the function inputs.
-**
-** P1 is a 32-bit bitmask indicating whether or not each argument to the 
-** function was determined to be constant at compile time. If the first
-** argument was constant then bit 0 of P1 is set. This is used to determine
-** whether meta data associated with a user function argument using the
-** sqlite3_set_auxdata() API may be safely retained until the next
-** invocation of this opcode.
-**
-** See also: AggStep and AggFinal
-*/
-case OP_Function: {
-  int i;
-  Mem *pArg;
-  sqlite3_context ctx;
-  sqlite3_value **apVal;
-  int n;
-
-  n = pOp->p5;
-  apVal = p->apArg;
-  assert( apVal || n==0 );
-
-  assert( n==0 || (pOp->p2>0 && pOp->p2+n<=p->nMem+1) );
-  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+n );
-  pArg = &p->aMem[pOp->p2];
-  for(i=0; i<n; i++, pArg++){
-    apVal[i] = pArg;
-    storeTypeInfo(pArg, encoding);
-    REGISTER_TRACE(pOp->p2, pArg);
-  }
-
-  assert( pOp->p4type==P4_FUNCDEF || pOp->p4type==P4_VDBEFUNC );
-  if( pOp->p4type==P4_FUNCDEF ){
-    ctx.pFunc = pOp->p4.pFunc;
-    ctx.pVdbeFunc = 0;
-  }else{
-    ctx.pVdbeFunc = (VdbeFunc*)pOp->p4.pVdbeFunc;
-    ctx.pFunc = ctx.pVdbeFunc->pFunc;
-  }
-
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pOut = &p->aMem[pOp->p3];
-  ctx.s.flags = MEM_Null;
-  ctx.s.db = db;
-  ctx.s.xDel = 0;
-  ctx.s.zMalloc = 0;
-
-  /* The output cell may already have a buffer allocated. Move
-  ** the pointer to ctx.s so in case the user-function can use
-  ** the already allocated buffer instead of allocating a new one.
-  */
-  sqlite3VdbeMemMove(&ctx.s, pOut);
-  MemSetTypeFlag(&ctx.s, MEM_Null);
-
-  ctx.isError = 0;
-  if( ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
-    assert( pOp>p->aOp );
-    assert( pOp[-1].p4type==P4_COLLSEQ );
-    assert( pOp[-1].opcode==OP_CollSeq );
-    ctx.pColl = pOp[-1].p4.pColl;
-  }
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  (*ctx.pFunc->xFunc)(&ctx, n, apVal);
-  if( sqlite3SafetyOn(db) ){
-    sqlite3VdbeMemRelease(&ctx.s);
-    goto abort_due_to_misuse;
-  }
-  if( db->mallocFailed ){
-    /* Even though a malloc() has failed, the implementation of the
-    ** user function may have called an sqlite3_result_XXX() function
-    ** to return a value. The following call releases any resources
-    ** associated with such a value.
-    **
-    ** Note: Maybe MemRelease() should be called if sqlite3SafetyOn()
-    ** fails also (the if(...) statement above). But if people are
-    ** misusing sqlite, they have bigger problems than a leaked value.
-    */
-    sqlite3VdbeMemRelease(&ctx.s);
-    goto no_mem;
-  }
-
-  /* If any auxiliary data functions have been called by this user function,
-  ** immediately call the destructor for any non-static values.
-  */
-  if( ctx.pVdbeFunc ){
-    sqlite3VdbeDeleteAuxData(ctx.pVdbeFunc, pOp->p1);
-    pOp->p4.pVdbeFunc = ctx.pVdbeFunc;
-    pOp->p4type = P4_VDBEFUNC;
-  }
-
-  /* If the function returned an error, throw an exception */
-  if( ctx.isError ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&ctx.s));
-    rc = ctx.isError;
-  }
-
-  /* Copy the result of the function into register P3 */
-  sqlite3VdbeChangeEncoding(&ctx.s, encoding);
-  sqlite3VdbeMemMove(pOut, &ctx.s);
-  if( sqlite3VdbeMemTooBig(pOut) ){
-    goto too_big;
-  }
-  REGISTER_TRACE(pOp->p3, pOut);
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
-}
-
-/* Opcode: BitAnd P1 P2 P3 * *
-**
-** 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 * *
-**
-** 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 * *
-**
-** Shift the integer value in register P2 to the left by the
-** number of bits specified by the integer in regiser P1.
-** Store the result in register P3.
-** If either input is NULL, the result is NULL.
-*/
-/* Opcode: ShiftRight P1 P2 P3 * *
-**
-** 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 */
-case OP_BitOr:                  /* same as TK_BITOR, in1, in2, out3 */
-case OP_ShiftLeft:              /* same as TK_LSHIFT, in1, in2, out3 */
-case OP_ShiftRight: {           /* same as TK_RSHIFT, in1, in2, out3 */
-  i64 a;
-  i64 b;
-
-  if( (pIn1->flags | pIn2->flags) & MEM_Null ){
-    sqlite3VdbeMemSetNull(pOut);
-    break;
-  }
-  a = sqlite3VdbeIntValue(pIn2);
-  b = sqlite3VdbeIntValue(pIn1);
-  switch( pOp->opcode ){
-    case OP_BitAnd:      a &= b;     break;
-    case OP_BitOr:       a |= b;     break;
-    case OP_ShiftLeft:   a <<= b;    break;
-    default:  assert( pOp->opcode==OP_ShiftRight );
-                         a >>= b;    break;
-  }
-  pOut->u.i = a;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
-}
-
-/* Opcode: AddImm  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 */
-  sqlite3VdbeMemIntegerify(pIn1);
-  pIn1->u.i += pOp->p2;
-  break;
-}
-
-/* Opcode: MustBeInt P1 P2 * * *
-** 
-** Force the value in register P1 to be an integer.  If the value
-** in P1 is not an integer and cannot be converted into an integer
-** without data loss, then jump immediately to P2, or if P2==0
-** raise an SQLITE_MISMATCH exception.
-*/
-case OP_MustBeInt: {            /* jump, in1 */
-  applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
-  if( (pIn1->flags & MEM_Int)==0 ){
-    if( pOp->p2==0 ){
-      rc = SQLITE_MISMATCH;
-      goto abort_due_to_error;
-    }else{
-      pc = pOp->p2 - 1;
-    }
-  }else{
-    MemSetTypeFlag(pIn1, MEM_Int);
-  }
-  break;
-}
-
-/* Opcode: RealAffinity P1 * * * *
-**
-** If register P1 holds an integer convert it to a real value.
-**
-** This opcode is used when extracting information from a column that
-** 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 */
-  if( pIn1->flags & MEM_Int ){
-    sqlite3VdbeMemRealify(pIn1);
-  }
-  break;
-}
-
-#ifndef SQLITE_OMIT_CAST
-/* Opcode: ToText P1 * * * *
-**
-** Force the value in register P1 to be text.
-** If the value is numeric, convert it to a string using the
-** equivalent of printf().  Blob values are unchanged and
-** are afterwards simply interpreted as text.
-**
-** A NULL value is not changed by this routine.  It remains NULL.
-*/
-case OP_ToText: {                  /* same as TK_TO_TEXT, in1 */
-  if( pIn1->flags & MEM_Null ) break;
-  assert( MEM_Str==(MEM_Blob>>3) );
-  pIn1->flags |= (pIn1->flags&MEM_Blob)>>3;
-  applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
-  rc = ExpandBlob(pIn1);
-  assert( pIn1->flags & MEM_Str || db->mallocFailed );
-  pIn1->flags &= ~(MEM_Int|MEM_Real|MEM_Blob|MEM_Zero);
-  UPDATE_MAX_BLOBSIZE(pIn1);
-  break;
-}
-
-/* Opcode: ToBlob P1 * * * *
-**
-** Force the value in register P1 to be a BLOB.
-** If the value is numeric, convert it to a string first.
-** Strings are simply reinterpreted as blobs with no change
-** to the underlying data.
-**
-** A NULL value is not changed by this routine.  It remains NULL.
-*/
-case OP_ToBlob: {                  /* same as TK_TO_BLOB, in1 */
-  if( pIn1->flags & MEM_Null ) break;
-  if( (pIn1->flags & MEM_Blob)==0 ){
-    applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
-    assert( pIn1->flags & MEM_Str || db->mallocFailed );
-    MemSetTypeFlag(pIn1, MEM_Blob);
-  }else{
-    pIn1->flags &= ~(MEM_TypeMask&~MEM_Blob);
-  }
-  UPDATE_MAX_BLOBSIZE(pIn1);
-  break;
-}
-
-/* Opcode: ToNumeric P1 * * * *
-**
-** Force the value in register P1 to be numeric (either an
-** integer or a floating-point number.)
-** If the value is text or blob, try to convert it to an using the
-** equivalent of atoi() or atof() and store 0 if no such conversion 
-** is possible.
-**
-** A NULL value is not changed by this routine.  It remains NULL.
-*/
-case OP_ToNumeric: {                  /* same as TK_TO_NUMERIC, in1 */
-  if( (pIn1->flags & (MEM_Null|MEM_Int|MEM_Real))==0 ){
-    sqlite3VdbeMemNumerify(pIn1);
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_CAST */
-
-/* Opcode: ToInt P1 * * * *
-**
-** Force the value in register P1 be an integer.  If
-** The value is currently a real number, drop its fractional part.
-** If the value is text or blob, try to convert it to an integer using the
-** equivalent of atoi() and store 0 if no such conversion is possible.
-**
-** A NULL value is not changed by this routine.  It remains NULL.
-*/
-case OP_ToInt: {                  /* same as TK_TO_INT, in1 */
-  if( (pIn1->flags & MEM_Null)==0 ){
-    sqlite3VdbeMemIntegerify(pIn1);
-  }
-  break;
-}
-
-#ifndef SQLITE_OMIT_CAST
-/* Opcode: ToReal P1 * * * *
-**
-** Force the value in register P1 to be a floating point number.
-** If The value is currently an integer, convert it.
-** If the value is text or blob, try to convert it to an integer using the
-** equivalent of atoi() and store 0.0 if no such conversion is possible.
-**
-** A NULL value is not changed by this routine.  It remains NULL.
-*/
-case OP_ToReal: {                  /* same as TK_TO_REAL, in1 */
-  if( (pIn1->flags & MEM_Null)==0 ){
-    sqlite3VdbeMemRealify(pIn1);
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_CAST */
-
-/* Opcode: Lt P1 P2 P3 P4 P5
-**
-** Compare the values in register P1 and P3.  If reg(P3)<reg(P1) then
-** jump to address P2.  
-**
-** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
-** reg(P3) is NULL then take the jump.  If the SQLITE_JUMPIFNULL 
-** bit is clear then fall thru if either operand is NULL.
-**
-** 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 
-** to coerce both inputs according to this affinity before the
-** comparison is made. If the SQLITE_AFF_MASK is 0x00, then numeric
-** affinity is used. Note that the affinity conversions are stored
-** back into the input registers P1 and P3.  So this opcode can cause
-** persistent changes to registers P1 and P3.
-**
-** Once any conversions have taken place, and neither value is NULL, 
-** the values are compared. If both values are blobs then memcmp() is
-** used to determine the results of the comparison.  If both values
-** are text, then the appropriate collating function specified in
-** 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.
-**
-** If the SQLITE_STOREP2 bit of P5 is set, then do not jump.  Instead,
-** store a boolean result (either 0, or 1, or NULL) in register P2.
-*/
-/* Opcode: Ne P1 P2 P3 P4 P5
-**
-** This works just like the Lt opcode except that the jump is taken if
-** the operands in registers P1 and P3 are not equal.  See the Lt opcode for
-** additional information.
-*/
-/* Opcode: Eq P1 P2 P3 P4 P5
-**
-** This works just like the Lt opcode except that the jump is taken if
-** the operands in registers P1 and P3 are equal.
-** See the Lt opcode for additional information.
-*/
-/* Opcode: Le P1 P2 P3 P4 P5
-**
-** 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
-**
-** 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
-**
-** 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 */
-case OP_Lt:               /* same as TK_LT, jump, in1, in3 */
-case OP_Le:               /* same as TK_LE, jump, in1, in3 */
-case OP_Gt:               /* same as TK_GT, jump, in1, in3 */
-case OP_Ge: {             /* same as TK_GE, jump, in1, in3 */
-  int flags;
-  int res;
-  char affinity;
-
-  flags = pIn1->flags|pIn3->flags;
-
-  if( flags&MEM_Null ){
-    /* If either operand is NULL then the result is always NULL.
-    ** The jump is taken if the SQLITE_JUMPIFNULL bit is set.
-    */
-    if( pOp->p5 & SQLITE_STOREP2 ){
-      pOut = &p->aMem[pOp->p2];
-      MemSetTypeFlag(pOut, MEM_Null);
-      REGISTER_TRACE(pOp->p2, pOut);
-    }else if( pOp->p5 & SQLITE_JUMPIFNULL ){
-      pc = pOp->p2-1;
-    }
-    break;
-  }
-
-  affinity = pOp->p5 & SQLITE_AFF_MASK;
-  if( affinity ){
-    applyAffinity(pIn1, affinity, encoding);
-    applyAffinity(pIn3, affinity, encoding);
-    if( db->mallocFailed ) goto no_mem;
-  }
-
-  assert( pOp->p4type==P4_COLLSEQ || pOp->p4.pColl==0 );
-  ExpandBlob(pIn1);
-  ExpandBlob(pIn3);
-  res = sqlite3MemCompare(pIn3, pIn1, pOp->p4.pColl);
-  switch( pOp->opcode ){
-    case OP_Eq:    res = res==0;     break;
-    case OP_Ne:    res = res!=0;     break;
-    case OP_Lt:    res = res<0;      break;
-    case OP_Le:    res = res<=0;     break;
-    case OP_Gt:    res = res>0;      break;
-    default:       res = res>=0;     break;
-  }
-
-  if( pOp->p5 & SQLITE_STOREP2 ){
-    pOut = &p->aMem[pOp->p2];
-    MemSetTypeFlag(pOut, MEM_Int);
-    pOut->u.i = res;
-    REGISTER_TRACE(pOp->p2, pOut);
-  }else if( res ){
-    pc = pOp->p2-1;
-  }
-  break;
-}
-
-/* Opcode: Permutation * * * P4 *
-**
-** Set the permutation used by the OP_Compare operator to be the array
-** of integers in P4.
-**
-** The permutation is only valid until the next OP_Permutation, OP_Compare,
-** OP_Halt, or OP_ResultRow.  Typically the OP_Permutation should occur
-** immediately prior to the OP_Compare.
-*/
-case OP_Permutation: {
-  assert( pOp->p4type==P4_INTARRAY );
-  assert( pOp->p4.ai );
-  aPermute = pOp->p4.ai;
-  break;
-}
-
-/* Opcode: Compare P1 P2 P3 P4 *
-**
-** Compare to vectors of registers in reg(P1)..reg(P1+P3-1) (all this
-** one "A") and in reg(P2)..reg(P2+P3-1) ("B").  Save the result of
-** the comparison for use by the next OP_Jump instruct.
-**
-** P4 is a KeyInfo structure that defines collating sequences and sort
-** orders for the comparison.  The permutation applies to registers
-** only.  The KeyInfo elements are used sequentially.
-**
-** The comparison is a sort comparison, so NULLs compare equal,
-** NULLs are less than numbers, numbers are less than strings,
-** and strings are less than blobs.
-*/
-case OP_Compare: {
-  int n;
-  int i;
-  int p1;
-  int p2;
-  const KeyInfo *pKeyInfo;
-  int idx;
-  CollSeq *pColl;    /* Collating sequence to use on this term */
-  int bRev;          /* True for DESCENDING sort order */
-
-  n = pOp->p3;
-  pKeyInfo = pOp->p4.pKeyInfo;
-  assert( n>0 );
-  assert( pKeyInfo!=0 );
-  p1 = pOp->p1;
-  assert( p1>0 && p1+n<=p->nMem+1 );
-  p2 = pOp->p2;
-  assert( p2>0 && p2+n<=p->nMem+1 );
-  for(i=0; i<n; i++){
-    idx = aPermute ? aPermute[i] : i;
-    REGISTER_TRACE(p1+idx, &p->aMem[p1+idx]);
-    REGISTER_TRACE(p2+idx, &p->aMem[p2+idx]);
-    assert( i<pKeyInfo->nField );
-    pColl = pKeyInfo->aColl[i];
-    bRev = pKeyInfo->aSortOrder[i];
-    iCompare = sqlite3MemCompare(&p->aMem[p1+idx], &p->aMem[p2+idx], pColl);
-    if( iCompare ){
-      if( bRev ) iCompare = -iCompare;
-      break;
-    }
-  }
-  aPermute = 0;
-  break;
-}
-
-/* Opcode: Jump P1 P2 P3 * *
-**
-** Jump to the instruction at address P1, P2, or P3 depending on whether
-** in the most recent OP_Compare instruction the P1 vector was less than
-** equal to, or greater than the P2 vector, respectively.
-*/
-case OP_Jump: {             /* jump */
-  if( iCompare<0 ){
-    pc = pOp->p1 - 1;
-  }else if( iCompare==0 ){
-    pc = pOp->p2 - 1;
-  }else{
-    pc = pOp->p3 - 1;
-  }
-  break;
-}
-
-/* Opcode: And P1 P2 P3 * *
-**
-** Take the logical AND of the values in registers P1 and P2 and
-** write the result into register P3.
-**
-** If either P1 or P2 is 0 (false) then the result is 0 even if
-** the other input is NULL.  A NULL and true or two NULLs give
-** a NULL output.
-*/
-/* Opcode: Or P1 P2 P3 * *
-**
-** Take the logical OR of the values in register P1 and P2 and
-** store the answer in register P3.
-**
-** If either P1 or P2 is nonzero (true) then the result is 1 (true)
-** even if the other input is NULL.  A NULL and false or two NULLs
-** give a NULL output.
-*/
-case OP_And:              /* same as TK_AND, in1, in2, out3 */
-case OP_Or: {             /* same as TK_OR, in1, in2, out3 */
-  int v1;    /* Left operand:  0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
-  int v2;    /* Right operand: 0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
-
-  if( pIn1->flags & MEM_Null ){
-    v1 = 2;
-  }else{
-    v1 = sqlite3VdbeIntValue(pIn1)!=0;
-  }
-  if( pIn2->flags & MEM_Null ){
-    v2 = 2;
-  }else{
-    v2 = sqlite3VdbeIntValue(pIn2)!=0;
-  }
-  if( pOp->opcode==OP_And ){
-    static const unsigned char and_logic[] = { 0, 0, 0, 0, 1, 2, 0, 2, 2 };
-    v1 = and_logic[v1*3+v2];
-  }else{
-    static const unsigned char or_logic[] = { 0, 1, 2, 1, 1, 1, 2, 1, 2 };
-    v1 = or_logic[v1*3+v2];
-  }
-  if( v1==2 ){
-    MemSetTypeFlag(pOut, MEM_Null);
-  }else{
-    pOut->u.i = v1;
-    MemSetTypeFlag(pOut, MEM_Int);
-  }
-  break;
-}
-
-/* Opcode: Not P1 P2 * * *
-**
-** Interpret the value in register P1 as a boolean value.  Store the
-** boolean complement in register P2.  If the value in register P1 is 
-** NULL, then a NULL is stored in P2.
-*/
-case OP_Not: {                /* same as TK_NOT, in1 */
-  pOut = &p->aMem[pOp->p2];
-  if( pIn1->flags & MEM_Null ){
-    sqlite3VdbeMemSetNull(pOut);
-  }else{
-    sqlite3VdbeMemSetInt64(pOut, !sqlite3VdbeIntValue(pIn1));
-  }
-  break;
-}
-
-/* Opcode: BitNot P1 P2 * * *
-**
-** Interpret the content of register P1 as an integer.  Store the
-** ones-complement of the P1 value into register P2.  If P1 holds
-** a NULL then store a NULL in P2.
-*/
-case OP_BitNot: {             /* same as TK_BITNOT, in1 */
-  pOut = &p->aMem[pOp->p2];
-  if( pIn1->flags & MEM_Null ){
-    sqlite3VdbeMemSetNull(pOut);
-  }else{
-    sqlite3VdbeMemSetInt64(pOut, ~sqlite3VdbeIntValue(pIn1));
-  }
-  break;
-}
-
-/* Opcode: If P1 P2 P3 * *
-**
-** Jump to P2 if the value in register P1 is true.  The value is
-** is considered true if it is numeric and non-zero.  If the value
-** in P1 is NULL then take the jump if P3 is true.
-*/
-/* Opcode: IfNot P1 P2 P3 * *
-**
-** Jump to P2 if the value in register P1 is False.  The value is
-** is considered true if it has a numeric value of zero.  If the value
-** in P1 is NULL then take the jump if P3 is true.
-*/
-case OP_If:                 /* jump, in1 */
-case OP_IfNot: {            /* jump, in1 */
-  int c;
-  if( pIn1->flags & MEM_Null ){
-    c = pOp->p3;
-  }else{
-#ifdef SQLITE_OMIT_FLOATING_POINT
-    c = sqlite3VdbeIntValue(pIn1)!=0;
-#else
-    c = sqlite3VdbeRealValue(pIn1)!=0.0;
-#endif
-    if( pOp->opcode==OP_IfNot ) c = !c;
-  }
-  if( c ){
-    pc = pOp->p2-1;
-  }
-  break;
-}
-
-/* Opcode: IsNull P1 P2 * * *
-**
-** Jump to P2 if the value in register P1 is NULL.
-*/
-case OP_IsNull: {            /* same as TK_ISNULL, jump, in1 */
-  if( (pIn1->flags & MEM_Null)!=0 ){
-    pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: NotNull P1 P2 * * *
-**
-** Jump to P2 if the value in register P1 is not NULL.  
-*/
-case OP_NotNull: {            /* same as TK_NOTNULL, jump, in1 */
-  if( (pIn1->flags & MEM_Null)==0 ){
-    pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: Column P1 P2 P3 P4 P5
-**
-** 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.
-**
-** The value extracted is stored in register P3.
-**
-** If the column contains fewer than P2 fields, then extract a NULL.  Or,
-** if the P4 argument is a P4_MEM use the value of the P4 argument as
-** the result.
-**
-** If the OPFLAG_CLEARCACHE bit is set on P5 and P1 is a pseudo-table cursor,
-** then the cache of the cursor is reset prior to extracting the column.
-** The first OP_Column against a pseudo-table after the value of the content
-** register has changed should have this bit set.
-*/
-case OP_Column: {
-  u32 payloadSize;   /* Number of bytes in the record */
-  i64 payloadSize64; /* Number of bytes in the record */
-  int p1;            /* P1 value of the opcode */
-  int p2;            /* column number to retrieve */
-  VdbeCursor *pC;    /* The VDBE cursor */
-  char *zRec;        /* Pointer to complete record-data */
-  BtCursor *pCrsr;   /* The BTree cursor */
-  u32 *aType;        /* aType[i] holds the numeric type of the i-th column */
-  u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
-  int nField;        /* number of fields in the record */
-  int len;           /* The length of the serialized data for the column */
-  int i;             /* Loop counter */
-  char *zData;       /* Part of the record being decoded */
-  Mem *pDest;        /* Where to write the extracted value */
-  Mem sMem;          /* For storing the record being decoded */
-  u8 *zIdx;          /* Index into header */
-  u8 *zEndHdr;       /* Pointer to first byte after the header */
-  u32 offset;        /* Offset into the data */
-  u64 offset64;      /* 64-bit offset.  64 bits needed to catch overflow */
-  int szHdr;         /* Size of the header size field at start of record */
-  int avail;         /* Number of bytes of available data */
-  Mem *pReg;         /* PseudoTable input register */
-
-
-  p1 = pOp->p1;
-  p2 = pOp->p2;
-  pC = 0;
-  memset(&sMem, 0, sizeof(sMem));
-  assert( p1<p->nCursor );
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pDest = &p->aMem[pOp->p3];
-  MemSetTypeFlag(pDest, MEM_Null);
-  zRec = 0;
-
-  /* This block sets the variable payloadSize to be the total number of
-  ** bytes in the record.
-  **
-  ** zRec is set to be the complete text of the record if it is available.
-  ** The complete record text is always available for pseudo-tables
-  ** If the record is stored in a cursor, the complete record text
-  ** might be available in the  pC->aRow cache.  Or it might not be.
-  ** If the data is unavailable,  zRec is set to NULL.
-  **
-  ** We also compute the number of columns in the record.  For cursors,
-  ** the number of columns is stored in the VdbeCursor.nField element.
-  */
-  pC = p->apCsr[p1];
-  assert( pC!=0 );
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  assert( pC->pVtabCursor==0 );
-#endif
-  pCrsr = pC->pCursor;
-  if( pCrsr!=0 ){
-    /* The record is stored in a B-Tree */
-    rc = sqlite3VdbeCursorMoveto(pC);
-    if( rc ) goto abort_due_to_error;
-    if( pC->nullRow ){
-      payloadSize = 0;
-    }else if( pC->cacheStatus==p->cacheCtr ){
-      payloadSize = pC->payloadSize;
-      zRec = (char*)pC->aRow;
-    }else if( pC->isIndex ){
-      assert( sqlite3BtreeCursorIsValid(pCrsr) );
-      rc = sqlite3BtreeKeySize(pCrsr, &payloadSize64);
-      assert( rc==SQLITE_OK );   /* True because of CursorMoveto() call above */
-      /* sqlite3BtreeParseCellPtr() uses getVarint32() to extract the
-      ** payload size, so it is impossible for payloadSize64 to be
-      ** larger than 32 bits. */
-      assert( (payloadSize64 & SQLITE_MAX_U32)==(u64)payloadSize64 );
-      payloadSize = (u32)payloadSize64;
-    }else{
-      assert( sqlite3BtreeCursorIsValid(pCrsr) );
-      rc = sqlite3BtreeDataSize(pCrsr, &payloadSize);
-      assert( rc==SQLITE_OK );   /* DataSize() cannot fail */
-    }
-  }else if( pC->pseudoTableReg>0 ){
-    pReg = &p->aMem[pC->pseudoTableReg];
-    assert( pReg->flags & MEM_Blob );
-    payloadSize = pReg->n;
-    zRec = pReg->z;
-    pC->cacheStatus = (pOp->p5&OPFLAG_CLEARCACHE) ? CACHE_STALE : p->cacheCtr;
-    assert( payloadSize==0 || zRec!=0 );
-  }else{
-    /* Consider the row to be NULL */
-    payloadSize = 0;
-  }
-
-  /* If payloadSize is 0, then just store a NULL */
-  if( payloadSize==0 ){
-    assert( pDest->flags&MEM_Null );
-    goto op_column_out;
-  }
-  assert( db->aLimit[SQLITE_LIMIT_LENGTH]>=0 );
-  if( payloadSize > (u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
-    goto too_big;
-  }
-
-  nField = pC->nField;
-  assert( p2<nField );
-
-  /* Read and parse the table header.  Store the results of the parse
-  ** into the record header cache fields of the cursor.
-  */
-  aType = pC->aType;
-  if( pC->cacheStatus==p->cacheCtr ){
-    aOffset = pC->aOffset;
-  }else{
-    assert(aType);
-    avail = 0;
-    pC->aOffset = aOffset = &aType[nField];
-    pC->payloadSize = payloadSize;
-    pC->cacheStatus = p->cacheCtr;
-
-    /* Figure out how many bytes are in the header */
-    if( zRec ){
-      zData = zRec;
-    }else{
-      if( pC->isIndex ){
-        zData = (char*)sqlite3BtreeKeyFetch(pCrsr, &avail);
-      }else{
-        zData = (char*)sqlite3BtreeDataFetch(pCrsr, &avail);
-      }
-      /* If KeyFetch()/DataFetch() managed to get the entire payload,
-      ** save the payload in the pC->aRow cache.  That will save us from
-      ** having to make additional calls to fetch the content portion of
-      ** the record.
-      */
-      assert( avail>=0 );
-      if( payloadSize <= (u32)avail ){
-        zRec = zData;
-        pC->aRow = (u8*)zData;
-      }else{
-        pC->aRow = 0;
-      }
-    }
-    /* The following assert is true in all cases accept when
-    ** the database file has been corrupted externally.
-    **    assert( zRec!=0 || avail>=payloadSize || avail>=9 ); */
-    szHdr = getVarint32((u8*)zData, offset);
-
-    /* Make sure a corrupt database has not given us an oversize header.
-    ** Do this now to avoid an oversize memory allocation.
-    **
-    ** Type entries can be between 1 and 5 bytes each.  But 4 and 5 byte
-    ** types use so much data space that there can only be 4096 and 32 of
-    ** them, respectively.  So the maximum header length results from a
-    ** 3-byte type for each of the maximum of 32768 columns plus three
-    ** extra bytes for the header length itself.  32768*3 + 3 = 98307.
-    */
-    if( offset > 98307 ){
-      rc = SQLITE_CORRUPT_BKPT;
-      goto op_column_out;
-    }
-
-    /* Compute in len the number of bytes of data we need to read in order
-    ** to get nField type values.  offset is an upper bound on this.  But
-    ** nField might be significantly less than the true number of columns
-    ** in the table, and in that case, 5*nField+3 might be smaller than offset.
-    ** We want to minimize len in order to limit the size of the memory
-    ** allocation, especially if a corrupt database file has caused offset
-    ** to be oversized. Offset is limited to 98307 above.  But 98307 might
-    ** still exceed Robson memory allocation limits on some configurations.
-    ** On systems that cannot tolerate large memory allocations, nField*5+3
-    ** will likely be much smaller since nField will likely be less than
-    ** 20 or so.  This insures that Robson memory allocation limits are
-    ** not exceeded even for corrupt database files.
-    */
-    len = nField*5 + 3;
-    if( len > (int)offset ) len = (int)offset;
-
-    /* The KeyFetch() or DataFetch() above are fast and will get the entire
-    ** record header in most cases.  But they will fail to get the complete
-    ** record header if the record header does not fit on a single page
-    ** in the B-Tree.  When that happens, use sqlite3VdbeMemFromBtree() to
-    ** acquire the complete header text.
-    */
-    if( !zRec && avail<len ){
-      sMem.flags = 0;
-      sMem.db = 0;
-      rc = sqlite3VdbeMemFromBtree(pCrsr, 0, len, pC->isIndex, &sMem);
-      if( rc!=SQLITE_OK ){
-        goto op_column_out;
-      }
-      zData = sMem.z;
-    }
-    zEndHdr = (u8 *)&zData[len];
-    zIdx = (u8 *)&zData[szHdr];
-
-    /* Scan the header and use it to fill in the aType[] and aOffset[]
-    ** arrays.  aType[i] will contain the type integer for the i-th
-    ** column and aOffset[i] will contain the offset from the beginning
-    ** of the record to the start of the data for the i-th column
-    */
-    offset64 = offset;
-    for(i=0; i<nField; i++){
-      if( zIdx<zEndHdr ){
-        aOffset[i] = (u32)offset64;
-        zIdx += getVarint32(zIdx, aType[i]);
-        offset64 += sqlite3VdbeSerialTypeLen(aType[i]);
-      }else{
-        /* If i is less that nField, then there are less fields in this
-        ** record than SetNumColumns indicated there are columns in the
-        ** table. Set the offset for any extra columns not present in
-        ** the record to 0. This tells code below to store a NULL
-        ** instead of deserializing a value from the record.
-        */
-        aOffset[i] = 0;
-      }
-    }
-    sqlite3VdbeMemRelease(&sMem);
-    sMem.flags = MEM_Null;
-
-    /* If we have read more header data than was contained in the header,
-    ** or if the end of the last field appears to be past the end of the
-    ** record, or if the end of the last field appears to be before the end
-    ** of the record (when all fields present), then we must be dealing 
-    ** with a corrupt database.
-    */
-    if( (zIdx > zEndHdr)|| (offset64 > payloadSize)
-     || (zIdx==zEndHdr && offset64!=(u64)payloadSize) ){
-      rc = SQLITE_CORRUPT_BKPT;
-      goto op_column_out;
-    }
-  }
-
-  /* Get the column information. If aOffset[p2] is non-zero, then 
-  ** deserialize the value from the record. If aOffset[p2] is zero,
-  ** then there are not enough fields in the record to satisfy the
-  ** request.  In this case, set the value NULL or to P4 if P4 is
-  ** a pointer to a Mem object.
-  */
-  if( aOffset[p2] ){
-    assert( rc==SQLITE_OK );
-    if( zRec ){
-      sqlite3VdbeMemReleaseExternal(pDest);
-      sqlite3VdbeSerialGet((u8 *)&zRec[aOffset[p2]], aType[p2], pDest);
-    }else{
-      len = sqlite3VdbeSerialTypeLen(aType[p2]);
-      sqlite3VdbeMemMove(&sMem, pDest);
-      rc = sqlite3VdbeMemFromBtree(pCrsr, aOffset[p2], len, pC->isIndex, &sMem);
-      if( rc!=SQLITE_OK ){
-        goto op_column_out;
-      }
-      zData = sMem.z;
-      sqlite3VdbeSerialGet((u8*)zData, aType[p2], pDest);
-    }
-    pDest->enc = encoding;
-  }else{
-    if( pOp->p4type==P4_MEM ){
-      sqlite3VdbeMemShallowCopy(pDest, pOp->p4.pMem, MEM_Static);
-    }else{
-      assert( pDest->flags&MEM_Null );
-    }
-  }
-
-  /* If we dynamically allocated space to hold the data (in the
-  ** sqlite3VdbeMemFromBtree() call above) then transfer control of that
-  ** dynamically allocated space over to the pDest structure.
-  ** This prevents a memory copy.
-  */
-  if( sMem.zMalloc ){
-    assert( sMem.z==sMem.zMalloc );
-    assert( !(pDest->flags & MEM_Dyn) );
-    assert( !(pDest->flags & (MEM_Blob|MEM_Str)) || pDest->z==sMem.z );
-    pDest->flags &= ~(MEM_Ephem|MEM_Static);
-    pDest->flags |= MEM_Term;
-    pDest->z = sMem.z;
-    pDest->zMalloc = sMem.zMalloc;
-  }
-
-  rc = sqlite3VdbeMemMakeWriteable(pDest);
-
-op_column_out:
-  UPDATE_MAX_BLOBSIZE(pDest);
-  REGISTER_TRACE(pOp->p3, pDest);
-  break;
-}
-
-/* Opcode: Affinity P1 P2 * P4 *
-**
-** Apply affinities to a range of P2 registers starting with P1.
-**
-** P4 is a string that is P2 characters long. The nth character of the
-** string indicates the column affinity that should be used for the nth
-** memory cell in the range.
-*/
-case OP_Affinity: {
-  char *zAffinity;   /* The affinity to be applied */
-  Mem *pData0;       /* First register to which to apply affinity */
-  Mem *pLast;        /* Last register to which to apply affinity */
-  Mem *pRec;         /* Current register */
-
-  zAffinity = pOp->p4.z;
-  pData0 = &p->aMem[pOp->p1];
-  pLast = &pData0[pOp->p2-1];
-  for(pRec=pData0; pRec<=pLast; pRec++){
-    ExpandBlob(pRec);
-    applyAffinity(pRec, zAffinity[pRec-pData0], encoding);
-  }
-  break;
-}
-
-/* Opcode: MakeRecord P1 P2 P3 P4 *
-**
-** Convert P2 registers beginning with P1 into a single entry
-** suitable for use as a data record in a database table or as a key
-** in an index.  The details of the format are irrelevant as long as
-** the OP_Column opcode can decode the record later.
-** Refer to source code comments for the details of the record
-** format.
-**
-** P4 may be a string that is P2 characters long.  The nth character of the
-** string indicates the column affinity that should be used for the nth
-** field of the index key.
-**
-** The mapping from character to affinity is given by the SQLITE_AFF_
-** macros defined in sqliteInt.h.
-**
-** If P4 is NULL then all index fields have the affinity NONE.
-*/
-case OP_MakeRecord: {
-  u8 *zNewRecord;        /* A buffer to hold the data for the new record */
-  Mem *pRec;             /* The new record */
-  u64 nData;             /* Number of bytes of data space */
-  int nHdr;              /* Number of bytes of header space */
-  i64 nByte;             /* Data space required for this record */
-  int nZero;             /* Number of zero bytes at the end of the record */
-  int nVarint;           /* Number of bytes in a varint */
-  u32 serial_type;       /* Type field */
-  Mem *pData0;           /* First field to be combined into the record */
-  Mem *pLast;            /* Last field of the record */
-  int nField;            /* Number of fields in the record */
-  char *zAffinity;       /* The affinity string for the record */
-  int file_format;       /* File format to use for encoding */
-  int i;                 /* Space used in zNewRecord[] */
-  int len;               /* Length of a field */
-
-  /* Assuming the record contains N fields, the record format looks
-  ** like this:
-  **
-  ** ------------------------------------------------------------------------
-  ** | hdr-size | type 0 | type 1 | ... | type N-1 | data0 | ... | data N-1 | 
-  ** ------------------------------------------------------------------------
-  **
-  ** Data(0) is taken from register P1.  Data(1) comes from register P1+1
-  ** and so froth.
-  **
-  ** Each type field is a varint representing the serial type of the 
-  ** corresponding data element (see sqlite3VdbeSerialType()). The
-  ** hdr-size field is also a varint which is the offset from the beginning
-  ** of the record to data0.
-  */
-  nData = 0;         /* Number of bytes of data space */
-  nHdr = 0;          /* Number of bytes of header space */
-  nByte = 0;         /* Data space required for this record */
-  nZero = 0;         /* Number of zero bytes at the end of the record */
-  nField = pOp->p1;
-  zAffinity = pOp->p4.z;
-  assert( nField>0 && pOp->p2>0 && pOp->p2+nField<=p->nMem+1 );
-  pData0 = &p->aMem[nField];
-  nField = pOp->p2;
-  pLast = &pData0[nField-1];
-  file_format = p->minWriteFileFormat;
-
-  /* Loop through the elements that will make up the record to figure
-  ** out how much space is required for the new record.
-  */
-  for(pRec=pData0; pRec<=pLast; pRec++){
-    if( zAffinity ){
-      applyAffinity(pRec, zAffinity[pRec-pData0], encoding);
-    }
-    if( pRec->flags&MEM_Zero && pRec->n>0 ){
-      sqlite3VdbeMemExpandBlob(pRec);
-    }
-    serial_type = sqlite3VdbeSerialType(pRec, file_format);
-    len = sqlite3VdbeSerialTypeLen(serial_type);
-    nData += len;
-    nHdr += sqlite3VarintLen(serial_type);
-    if( pRec->flags & MEM_Zero ){
-      /* Only pure zero-filled BLOBs can be input to this Opcode.
-      ** We do not allow blobs with a prefix and a zero-filled tail. */
-      nZero += pRec->u.nZero;
-    }else if( len ){
-      nZero = 0;
-    }
-  }
-
-  /* Add the initial header varint and total the size */
-  nHdr += nVarint = sqlite3VarintLen(nHdr);
-  if( nVarint<sqlite3VarintLen(nHdr) ){
-    nHdr++;
-  }
-  nByte = nHdr+nData-nZero;
-  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-    goto too_big;
-  }
-
-  /* Make sure the output register has a buffer large enough to store 
-  ** the new record. The output register (pOp->p3) is not allowed to
-  ** be one of the input registers (because the following call to
-  ** sqlite3VdbeMemGrow() could clobber the value before it is used).
-  */
-  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
-  pOut = &p->aMem[pOp->p3];
-  if( sqlite3VdbeMemGrow(pOut, (int)nByte, 0) ){
-    goto no_mem;
-  }
-  zNewRecord = (u8 *)pOut->z;
-
-  /* Write the record */
-  i = putVarint32(zNewRecord, nHdr);
-  for(pRec=pData0; pRec<=pLast; pRec++){
-    serial_type = sqlite3VdbeSerialType(pRec, file_format);
-    i += putVarint32(&zNewRecord[i], serial_type);      /* serial type */
-  }
-  for(pRec=pData0; pRec<=pLast; pRec++){  /* serial data */
-    i += sqlite3VdbeSerialPut(&zNewRecord[i], (int)(nByte-i), pRec,file_format);
-  }
-  assert( i==nByte );
-
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pOut->n = (int)nByte;
-  pOut->flags = MEM_Blob | MEM_Dyn;
-  pOut->xDel = 0;
-  if( nZero ){
-    pOut->u.nZero = nZero;
-    pOut->flags |= MEM_Zero;
-  }
-  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever converted to text */
-  REGISTER_TRACE(pOp->p3, pOut);
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
-}
-
-/* Opcode: Count P1 P2 * * *
-**
-** Store the number of entries (an integer value) in the table or index 
-** opened by cursor P1 in register P2
-*/
-#ifndef SQLITE_OMIT_BTREECOUNT
-case OP_Count: {         /* out2-prerelease */
-  i64 nEntry;
-  BtCursor *pCrsr;
-
-  pCrsr = p->apCsr[pOp->p1]->pCursor;
-  if( pCrsr ){
-    rc = sqlite3BtreeCount(pCrsr, &nEntry);
-  }else{
-    nEntry = 0;
-  }
-  pOut->flags = MEM_Int;
-  pOut->u.i = nEntry;
-  break;
-}
-#endif
-
-/* Opcode: Savepoint P1 * * P4 *
-**
-** Open, release or rollback the savepoint named by parameter P4, depending
-** on the value of P1. To open a new savepoint, P1==0. To release (commit) an
-** existing savepoint, P1==1, or to rollback an existing savepoint P1==2.
-*/
-case OP_Savepoint: {
-  int p1;                         /* Value of P1 operand */
-  char *zName;                    /* Name of savepoint */
-  int nName;
-  Savepoint *pNew;
-  Savepoint *pSavepoint;
-  Savepoint *pTmp;
-  int iSavepoint;
-  int ii;
-
-  p1 = pOp->p1;
-  zName = pOp->p4.z;
-
-  /* Assert that the p1 parameter is valid. Also that if there is no open
-  ** transaction, then there cannot be any savepoints. 
-  */
-  assert( db->pSavepoint==0 || db->autoCommit==0 );
-  assert( p1==SAVEPOINT_BEGIN||p1==SAVEPOINT_RELEASE||p1==SAVEPOINT_ROLLBACK );
-  assert( db->pSavepoint || db->isTransactionSavepoint==0 );
-  assert( checkSavepointCount(db) );
-
-  if( p1==SAVEPOINT_BEGIN ){
-    if( db->writeVdbeCnt>0 ){
-      /* A new savepoint cannot be created if there are active write 
-      ** statements (i.e. open read/write incremental blob handles).
-      */
-      sqlite3SetString(&p->zErrMsg, db, "cannot open savepoint - "
-        "SQL statements in progress");
-      rc = SQLITE_BUSY;
-    }else{
-      nName = sqlite3Strlen30(zName);
-
-      /* Create a new savepoint structure. */
-      pNew = sqlite3DbMallocRaw(db, sizeof(Savepoint)+nName+1);
-      if( pNew ){
-        pNew->zName = (char *)&pNew[1];
-        memcpy(pNew->zName, zName, nName+1);
-    
-        /* If there is no open transaction, then mark this as a special
-        ** "transaction savepoint". */
-        if( db->autoCommit ){
-          db->autoCommit = 0;
-          db->isTransactionSavepoint = 1;
-        }else{
-          db->nSavepoint++;
-        }
-    
-        /* Link the new savepoint into the database handle's list. */
-        pNew->pNext = db->pSavepoint;
-        db->pSavepoint = pNew;
-      }
-    }
-  }else{
-    iSavepoint = 0;
-
-    /* Find the named savepoint. If there is no such savepoint, then an
-    ** an error is returned to the user.  */
-    for(
-      pSavepoint = db->pSavepoint; 
-      pSavepoint && sqlite3StrICmp(pSavepoint->zName, zName);
-      pSavepoint = pSavepoint->pNext
-    ){
-      iSavepoint++;
-    }
-    if( !pSavepoint ){
-      sqlite3SetString(&p->zErrMsg, db, "no such savepoint: %s", zName);
-      rc = SQLITE_ERROR;
-    }else if( 
-        db->writeVdbeCnt>0 || (p1==SAVEPOINT_ROLLBACK && db->activeVdbeCnt>1) 
-    ){
-      /* It is not possible to release (commit) a savepoint if there are 
-      ** active write statements. It is not possible to rollback a savepoint
-      ** if there are any active statements at all.
-      */
-      sqlite3SetString(&p->zErrMsg, db, 
-        "cannot %s savepoint - SQL statements in progress",
-        (p1==SAVEPOINT_ROLLBACK ? "rollback": "release")
-      );
-      rc = SQLITE_BUSY;
-    }else{
-
-      /* Determine whether or not this is a transaction savepoint. If so,
-      ** and this is a RELEASE command, then the current transaction 
-      ** is committed. 
-      */
-      int isTransaction = pSavepoint->pNext==0 && db->isTransactionSavepoint;
-      if( isTransaction && p1==SAVEPOINT_RELEASE ){
-        db->autoCommit = 1;
-        if( sqlite3VdbeHalt(p)==SQLITE_BUSY ){
-          p->pc = pc;
-          db->autoCommit = 0;
-          p->rc = rc = SQLITE_BUSY;
-          goto vdbe_return;
-        }
-        db->isTransactionSavepoint = 0;
-        rc = p->rc;
-      }else{
-        iSavepoint = db->nSavepoint - iSavepoint - 1;
-        for(ii=0; ii<db->nDb; ii++){
-          rc = sqlite3BtreeSavepoint(db->aDb[ii].pBt, p1, iSavepoint);
-          if( rc!=SQLITE_OK ){
-            goto abort_due_to_error;
-          }
-        }
-        if( p1==SAVEPOINT_ROLLBACK && (db->flags&SQLITE_InternChanges)!=0 ){
-          sqlite3ExpirePreparedStatements(db);
-          sqlite3ResetInternalSchema(db, 0);
-        }
-      }
-  
-      /* Regardless of whether this is a RELEASE or ROLLBACK, destroy all 
-      ** savepoints nested inside of the savepoint being operated on. */
-      while( db->pSavepoint!=pSavepoint ){
-        pTmp = db->pSavepoint;
-        db->pSavepoint = pTmp->pNext;
-        sqlite3DbFree(db, pTmp);
-        db->nSavepoint--;
-      }
-
-      /* If it is a RELEASE, then destroy the savepoint being operated on too */
-      if( p1==SAVEPOINT_RELEASE ){
-        assert( pSavepoint==db->pSavepoint );
-        db->pSavepoint = pSavepoint->pNext;
-        sqlite3DbFree(db, pSavepoint);
-        if( !isTransaction ){
-          db->nSavepoint--;
-        }
-      }
-    }
-  }
-
-  break;
-}
-
-/* Opcode: AutoCommit P1 P2 * * *
-**
-** Set the database auto-commit flag to P1 (1 or 0). If P2 is true, roll
-** back any currently active btree transactions. If there are any active
-** VMs (apart from this one), then a ROLLBACK fails.  A COMMIT fails if
-** there are active writing VMs or active VMs that use shared cache.
-**
-** This instruction causes the VM to halt.
-*/
-case OP_AutoCommit: {
-  int desiredAutoCommit;
-  int iRollback;
-  int turnOnAC;
-
-  desiredAutoCommit = pOp->p1;
-  iRollback = pOp->p2;
-  turnOnAC = desiredAutoCommit && !db->autoCommit;
-  assert( desiredAutoCommit==1 || desiredAutoCommit==0 );
-  assert( desiredAutoCommit==1 || iRollback==0 );
-  assert( db->activeVdbeCnt>0 );  /* At least this one VM is active */
-
-  if( turnOnAC && iRollback && db->activeVdbeCnt>1 ){
-    /* If this instruction implements a ROLLBACK and other VMs are
-    ** still running, and a transaction is active, return an error indicating
-    ** that the other VMs must complete first. 
-    */
-    sqlite3SetString(&p->zErrMsg, db, "cannot rollback transaction - "
-        "SQL statements in progress");
-    rc = SQLITE_BUSY;
-  }else if( turnOnAC && !iRollback && db->writeVdbeCnt>0 ){
-    /* If this instruction implements a COMMIT and other VMs are writing
-    ** return an error indicating that the other VMs must complete first. 
-    */
-    sqlite3SetString(&p->zErrMsg, db, "cannot commit transaction - "
-        "SQL statements in progress");
-    rc = SQLITE_BUSY;
-  }else if( desiredAutoCommit!=db->autoCommit ){
-    if( iRollback ){
-      assert( desiredAutoCommit==1 );
-      sqlite3RollbackAll(db);
-      db->autoCommit = 1;
-    }else{
-      db->autoCommit = (u8)desiredAutoCommit;
-      if( sqlite3VdbeHalt(p)==SQLITE_BUSY ){
-        p->pc = pc;
-        db->autoCommit = (u8)(1-desiredAutoCommit);
-        p->rc = rc = SQLITE_BUSY;
-        goto vdbe_return;
-      }
-    }
-    assert( db->nStatement==0 );
-    sqlite3CloseSavepoints(db);
-    if( p->rc==SQLITE_OK ){
-      rc = SQLITE_DONE;
-    }else{
-      rc = SQLITE_ERROR;
-    }
-    goto vdbe_return;
-  }else{
-    sqlite3SetString(&p->zErrMsg, db,
-        (!desiredAutoCommit)?"cannot start a transaction within a transaction":(
-        (iRollback)?"cannot rollback - no transaction is active":
-                   "cannot commit - no transaction is active"));
-         
-    rc = SQLITE_ERROR;
-  }
-  break;
-}
-
-/* Opcode: Transaction P1 P2 * * *
-**
-** Begin a transaction.  The transaction ends when a Commit or Rollback
-** opcode is encountered.  Depending on the ON CONFLICT setting, the
-** transaction might also be rolled back if an error is encountered.
-**
-** P1 is the index of the database file on which the transaction is
-** started.  Index 0 is the main database file and index 1 is the
-** file used for temporary tables.  Indices of 2 or more are used for
-** attached databases.
-**
-** If P2 is non-zero, then a write-transaction is started.  A RESERVED lock is
-** obtained on the database file when a write-transaction is started.  No
-** other process can start another write transaction while this transaction is
-** underway.  Starting a write transaction also creates a rollback journal. A
-** write transaction must be started before any changes can be made to the
-** database.  If P2 is 2 or greater then an EXCLUSIVE lock is also obtained
-** on the file.
-**
-** If a write-transaction is started and the Vdbe.usesStmtJournal flag is
-** true (this flag is set if the Vdbe may modify more than one row and may
-** throw an ABORT exception), a statement transaction may also be opened.
-** More specifically, a statement transaction is opened iff the database
-** connection is currently not in autocommit mode, or if there are other
-** active statements. A statement transaction allows the affects of this
-** VDBE to be rolled back after an error without having to roll back the
-** entire transaction. If no error is encountered, the statement transaction
-** will automatically commit when the VDBE halts.
-**
-** If P2 is zero, then a read-lock is obtained on the database file.
-*/
-case OP_Transaction: {
-  Btree *pBt;
-
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pBt = db->aDb[pOp->p1].pBt;
-
-  if( pBt ){
-    rc = sqlite3BtreeBeginTrans(pBt, pOp->p2);
-    if( rc==SQLITE_BUSY ){
-      p->pc = pc;
-      p->rc = rc = SQLITE_BUSY;
-      goto vdbe_return;
-    }
-    if( rc!=SQLITE_OK && rc!=SQLITE_READONLY /* && rc!=SQLITE_BUSY */ ){
-      goto abort_due_to_error;
-    }
-
-    if( pOp->p2 && p->usesStmtJournal 
-     && (db->autoCommit==0 || db->activeVdbeCnt>1) 
-    ){
-      assert( sqlite3BtreeIsInTrans(pBt) );
-      if( p->iStatement==0 ){
-        assert( db->nStatement>=0 && db->nSavepoint>=0 );
-        db->nStatement++; 
-        p->iStatement = db->nSavepoint + db->nStatement;
-      }
-      rc = sqlite3BtreeBeginStmt(pBt, p->iStatement);
-    }
-  }
-  break;
-}
-
-/* Opcode: ReadCookie P1 P2 P3 * *
-**
-** Read cookie number P3 from database P1 and write it into register P2.
-** P3==1 is the schema version.  P3==2 is the database format.
-** P3==3 is the recommended pager cache size, and so forth.  P1==0 is
-** the main database file and P1==1 is the database file used to store
-** temporary tables.
-**
-** There must be a read-lock on the database (either a transaction
-** must be started or there must be an open cursor) before
-** executing this instruction.
-*/
-case OP_ReadCookie: {               /* out2-prerelease */
-  int iMeta;
-  int iDb;
-  int iCookie;
-
-  iDb = pOp->p1;
-  iCookie = pOp->p3;
-  assert( pOp->p3<SQLITE_N_BTREE_META );
-  assert( iDb>=0 && iDb<db->nDb );
-  assert( db->aDb[iDb].pBt!=0 );
-  assert( (p->btreeMask & (1<<iDb))!=0 );
-
-  sqlite3BtreeGetMeta(db->aDb[iDb].pBt, iCookie, (u32 *)&iMeta);
-  pOut->u.i = iMeta;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
-}
-
-/* Opcode: SetCookie P1 P2 P3 * *
-**
-** Write the content of register P3 (interpreted as an integer)
-** into cookie number P2 of database P1.  P2==1 is the schema version.  
-** P2==2 is the database format. P2==3 is the recommended pager cache 
-** size, and so forth.  P1==0 is the main database file and P1==1 is the 
-** database file used to store temporary tables.
-**
-** A transaction must be started before executing this opcode.
-*/
-case OP_SetCookie: {       /* in3 */
-  Db *pDb;
-  assert( pOp->p2<SQLITE_N_BTREE_META );
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pDb = &db->aDb[pOp->p1];
-  assert( pDb->pBt!=0 );
-  sqlite3VdbeMemIntegerify(pIn3);
-  /* See note about index shifting on OP_ReadCookie */
-  rc = sqlite3BtreeUpdateMeta(pDb->pBt, pOp->p2, (int)pIn3->u.i);
-  if( pOp->p2==BTREE_SCHEMA_VERSION ){
-    /* When the schema cookie changes, record the new cookie internally */
-    pDb->pSchema->schema_cookie = (int)pIn3->u.i;
-    db->flags |= SQLITE_InternChanges;
-  }else if( pOp->p2==BTREE_FILE_FORMAT ){
-    /* Record changes in the file format */
-    pDb->pSchema->file_format = (u8)pIn3->u.i;
-  }
-  if( pOp->p1==1 ){
-    /* Invalidate all prepared statements whenever the TEMP database
-    ** schema is changed.  Ticket #1644 */
-    sqlite3ExpirePreparedStatements(db);
-  }
-  break;
-}
-
-/* Opcode: VerifyCookie P1 P2 *
-**
-** Check the value of global database parameter number 0 (the
-** schema version) and make sure it is equal to P2.  
-** P1 is the database number which is 0 for the main database file
-** and 1 for the file holding temporary tables and some higher number
-** for auxiliary databases.
-**
-** The cookie changes its value whenever the database schema changes.
-** This operation is used to detect when that the cookie has changed
-** and that the current process needs to reread the schema.
-**
-** Either a transaction needs to have been started or an OP_Open needs
-** to be executed (to establish a read lock) before this opcode is
-** invoked.
-*/
-case OP_VerifyCookie: {
-  int iMeta;
-  Btree *pBt;
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pBt = db->aDb[pOp->p1].pBt;
-  if( pBt ){
-    sqlite3BtreeGetMeta(pBt, BTREE_SCHEMA_VERSION, (u32 *)&iMeta);
-  }else{
-    iMeta = 0;
-  }
-  if( iMeta!=pOp->p2 ){
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
-    /* If the schema-cookie from the database file matches the cookie 
-    ** stored with the in-memory representation of the schema, do
-    ** not reload the schema from the database file.
-    **
-    ** If virtual-tables are in use, this is not just an optimization.
-    ** Often, v-tables store their data in other SQLite tables, which
-    ** are queried from within xNext() and other v-table methods using
-    ** prepared queries. If such a query is out-of-date, we do not want to
-    ** discard the database schema, as the user code implementing the
-    ** v-table would have to be ready for the sqlite3_vtab structure itself
-    ** to be invalidated whenever sqlite3_step() is called from within 
-    ** a v-table method.
-    */
-    if( db->aDb[pOp->p1].pSchema->schema_cookie!=iMeta ){
-      sqlite3ResetInternalSchema(db, pOp->p1);
-    }
-
-    sqlite3ExpirePreparedStatements(db);
-    rc = SQLITE_SCHEMA;
-  }
-  break;
-}
-
-/* Opcode: OpenRead P1 P2 P3 P4 P5
-**
-** Open a read-only cursor for the database table whose root page is
-** P2 in a database file.  The database file is determined by P3. 
-** P3==0 means the main database, P3==1 means the database used for 
-** temporary tables, and P3>1 means used the corresponding attached
-** database.  Give the new cursor an identifier of P1.  The P1
-** values need not be contiguous but all P1 values should be small integers.
-** It is an error for P1 to be negative.
-**
-** If P5!=0 then use the content of register P2 as the root page, not
-** the value of P2 itself.
-**
-** There will be a read lock on the database whenever there is an
-** open cursor.  If the database was unlocked prior to this instruction
-** then a read lock is acquired as part of this instruction.  A read
-** lock allows other processes to read the database but prohibits
-** any other process from modifying the database.  The read lock is
-** released when all cursors are closed.  If this instruction attempts
-** to get a read lock but fails, the script terminates with an
-** SQLITE_BUSY error code.
-**
-** The P4 value may be either an integer (P4_INT32) or a pointer to
-** a KeyInfo structure (P4_KEYINFO). If it is a pointer to a KeyInfo 
-** structure, then said structure defines the content and collating 
-** sequence of the index being opened. Otherwise, if P4 is an integer 
-** value, it is set to the number of columns in the table.
-**
-** See also OpenWrite.
-*/
-/* Opcode: OpenWrite P1 P2 P3 P4 P5
-**
-** Open a read/write cursor named P1 on the table or index whose root
-** page is P2.  Or if P5!=0 use the content of register P2 to find the
-** root page.
-**
-** The P4 value may be either an integer (P4_INT32) or a pointer to
-** a KeyInfo structure (P4_KEYINFO). If it is a pointer to a KeyInfo 
-** structure, then said structure defines the content and collating 
-** sequence of the index being opened. Otherwise, if P4 is an integer 
-** value, it is set to the number of columns in the table, or to the
-** largest index of any column of the table that is actually used.
-**
-** This instruction works just like OpenRead except that it opens the cursor
-** in read/write mode.  For a given table, there can be one or more read-only
-** cursors or a single read/write cursor but not both.
-**
-** See also OpenRead.
-*/
-case OP_OpenRead:
-case OP_OpenWrite: {
-  int nField;
-  KeyInfo *pKeyInfo;
-  int p2;
-  int iDb;
-  int wrFlag;
-  Btree *pX;
-  VdbeCursor *pCur;
-  Db *pDb;
-
-  nField = 0;
-  pKeyInfo = 0;
-  p2 = pOp->p2;
-  iDb = pOp->p3;
-  assert( iDb>=0 && iDb<db->nDb );
-  assert( (p->btreeMask & (1<<iDb))!=0 );
-  pDb = &db->aDb[iDb];
-  pX = pDb->pBt;
-  assert( pX!=0 );
-  if( pOp->opcode==OP_OpenWrite ){
-    wrFlag = 1;
-    if( pDb->pSchema->file_format < p->minWriteFileFormat ){
-      p->minWriteFileFormat = pDb->pSchema->file_format;
-    }
-  }else{
-    wrFlag = 0;
-  }
-  if( pOp->p5 ){
-    assert( p2>0 );
-    assert( p2<=p->nMem );
-    pIn2 = &p->aMem[p2];
-    sqlite3VdbeMemIntegerify(pIn2);
-    p2 = (int)pIn2->u.i;
-    /* The p2 value always comes from a prior OP_CreateTable opcode and
-    ** that opcode will always set the p2 value to 2 or more or else fail.
-    ** If there were a failure, the prepared statement would have halted
-    ** before reaching this instruction. */
-    if( NEVER(p2<2) ) {
-      rc = SQLITE_CORRUPT_BKPT;
-      goto abort_due_to_error;
-    }
-  }
-  if( pOp->p4type==P4_KEYINFO ){
-    pKeyInfo = pOp->p4.pKeyInfo;
-    pKeyInfo->enc = ENC(p->db);
-    nField = pKeyInfo->nField+1;
-  }else if( pOp->p4type==P4_INT32 ){
-    nField = pOp->p4.i;
-  }
-  assert( pOp->p1>=0 );
-  pCur = allocateCursor(p, pOp->p1, nField, iDb, 1);
-  if( pCur==0 ) goto no_mem;
-  pCur->nullRow = 1;
-  rc = sqlite3BtreeCursor(pX, p2, wrFlag, pKeyInfo, pCur->pCursor);
-  pCur->pKeyInfo = pKeyInfo;
-
-  /* Since it performs no memory allocation or IO, the only values that
-  ** sqlite3BtreeCursor() may return are SQLITE_EMPTY and SQLITE_OK. 
-  ** SQLITE_EMPTY is only returned when attempting to open the table
-  ** rooted at page 1 of a zero-byte database.  */
-  assert( rc==SQLITE_EMPTY || rc==SQLITE_OK );
-  if( rc==SQLITE_EMPTY ){
-    pCur->pCursor = 0;
-    rc = SQLITE_OK;
-  }
-
-  /* Set the VdbeCursor.isTable and isIndex variables. Previous versions of
-  ** SQLite used to check if the root-page flags were sane at this point
-  ** and report database corruption if they were not, but this check has
-  ** since moved into the btree layer.  */  
-  pCur->isTable = pOp->p4type!=P4_KEYINFO;
-  pCur->isIndex = !pCur->isTable;
-  break;
-}
-
-/* Opcode: OpenEphemeral P1 P2 * P4 *
-**
-** Open a new cursor P1 to a transient table.
-** The cursor is always opened read/write even if 
-** the main database is read-only.  The transient or virtual
-** table is deleted automatically when the cursor is closed.
-**
-** P2 is the number of columns in the virtual table.
-** The cursor points to a BTree table if P4==0 and to a BTree index
-** if P4 is not 0.  If P4 is not NULL, it points to a KeyInfo structure
-** that defines the format of keys in the index.
-**
-** This opcode was once called OpenTemp.  But that created
-** confusion because the term "temp table", might refer either
-** to a TEMP table at the SQL level, or to a table opened by
-** this opcode.  Then this opcode was call OpenVirtual.  But
-** that created confusion with the whole virtual-table idea.
-*/
-case OP_OpenEphemeral: {
-  VdbeCursor *pCx;
-  static const int openFlags = 
-      SQLITE_OPEN_READWRITE |
-      SQLITE_OPEN_CREATE |
-      SQLITE_OPEN_EXCLUSIVE |
-      SQLITE_OPEN_DELETEONCLOSE |
-      SQLITE_OPEN_TRANSIENT_DB;
-
-  assert( pOp->p1>=0 );
-  pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
-  if( pCx==0 ) goto no_mem;
-  pCx->nullRow = 1;
-  rc = sqlite3BtreeFactory(db, 0, 1, SQLITE_DEFAULT_TEMP_CACHE_SIZE, openFlags,
-                           &pCx->pBt);
-  if( rc==SQLITE_OK ){
-    rc = sqlite3BtreeBeginTrans(pCx->pBt, 1);
-  }
-  if( rc==SQLITE_OK ){
-    /* If a transient index is required, create it by calling
-    ** sqlite3BtreeCreateTable() with the BTREE_ZERODATA flag before
-    ** opening it. If a transient table is required, just use the
-    ** automatically created table with root-page 1 (an INTKEY table).
-    */
-    if( pOp->p4.pKeyInfo ){
-      int pgno;
-      assert( pOp->p4type==P4_KEYINFO );
-      rc = sqlite3BtreeCreateTable(pCx->pBt, &pgno, BTREE_ZERODATA); 
-      if( rc==SQLITE_OK ){
-        assert( pgno==MASTER_ROOT+1 );
-        rc = sqlite3BtreeCursor(pCx->pBt, pgno, 1, 
-                                (KeyInfo*)pOp->p4.z, pCx->pCursor);
-        pCx->pKeyInfo = pOp->p4.pKeyInfo;
-        pCx->pKeyInfo->enc = ENC(p->db);
-      }
-      pCx->isTable = 0;
-    }else{
-      rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, 1, 0, pCx->pCursor);
-      pCx->isTable = 1;
-    }
-  }
-  pCx->isIndex = !pCx->isTable;
-  break;
-}
-
-/* Opcode: OpenPseudo P1 P2 P3 * *
-**
-** Open a new cursor that points to a fake table that contains a single
-** row of data.  The content of that one row in the content of memory
-** register P2.  In other words, cursor P1 becomes an alias for the 
-** MEM_Blob content contained in register P2.
-**
-** A pseudo-table created by this opcode is used to hold the a single
-** row output from the sorter so that the row can be decomposed into
-** individual columns using the OP_Column opcode.  The OP_Column opcode
-** is the only cursor opcode that works with a pseudo-table.
-**
-** P3 is the number of fields in the records that will be stored by
-** the pseudo-table.
-*/
-case OP_OpenPseudo: {
-  VdbeCursor *pCx;
-
-  assert( pOp->p1>=0 );
-  pCx = allocateCursor(p, pOp->p1, pOp->p3, -1, 0);
-  if( pCx==0 ) goto no_mem;
-  pCx->nullRow = 1;
-  pCx->pseudoTableReg = pOp->p2;
-  pCx->isTable = 1;
-  pCx->isIndex = 0;
-  break;
-}
-
-/* Opcode: Close P1 * * * *
-**
-** Close a cursor previously opened as P1.  If P1 is not
-** currently open, this instruction is a no-op.
-*/
-case OP_Close: {
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  sqlite3VdbeFreeCursor(p, p->apCsr[pOp->p1]);
-  p->apCsr[pOp->p1] = 0;
-  break;
-}
-
-/* Opcode: SeekGe P1 P2 P3 P4 *
-**
-** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
-** use the value in register P3 as the key.  If cursor P1 refers 
-** to an SQL index, then P3 is the first in an array of P4 registers 
-** that are used as an unpacked index key. 
-**
-** Reposition cursor P1 so that  it points to the smallest entry that 
-** is greater than or equal to the key value. If there are no records 
-** greater than or equal to the key and P2 is not zero, then jump to P2.
-**
-** See also: Found, NotFound, Distinct, SeekLt, SeekGt, SeekLe
-*/
-/* Opcode: SeekGt P1 P2 P3 P4 *
-**
-** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
-** use the value in register P3 as a key. If cursor P1 refers 
-** to an SQL index, then P3 is the first in an array of P4 registers 
-** that are used as an unpacked index key. 
-**
-** Reposition cursor P1 so that  it points to the smallest entry that 
-** is greater than the key value. If there are no records greater than 
-** the key and P2 is not zero, then jump to P2.
-**
-** See also: Found, NotFound, Distinct, SeekLt, SeekGe, SeekLe
-*/
-/* Opcode: SeekLt P1 P2 P3 P4 * 
-**
-** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
-** use the value in register P3 as a key. If cursor P1 refers 
-** to an SQL index, then P3 is the first in an array of P4 registers 
-** that are used as an unpacked index key. 
-**
-** Reposition cursor P1 so that  it points to the largest entry that 
-** is less than the key value. If there are no records less than 
-** the key and P2 is not zero, then jump to P2.
-**
-** See also: Found, NotFound, Distinct, SeekGt, SeekGe, SeekLe
-*/
-/* Opcode: SeekLe P1 P2 P3 P4 *
-**
-** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
-** use the value in register P3 as a key. If cursor P1 refers 
-** to an SQL index, then P3 is the first in an array of P4 registers 
-** that are used as an unpacked index key. 
-**
-** Reposition cursor P1 so that it points to the largest entry that 
-** is less than or equal to the key value. If there are no records 
-** less than or equal to the key and P2 is not zero, then jump to P2.
-**
-** See also: Found, NotFound, Distinct, SeekGt, SeekGe, SeekLt
-*/
-case OP_SeekLt:         /* jump, in3 */
-case OP_SeekLe:         /* jump, in3 */
-case OP_SeekGe:         /* jump, in3 */
-case OP_SeekGt: {       /* jump, in3 */
-  int res;
-  int oc;
-  VdbeCursor *pC;
-  UnpackedRecord r;
-  int nField;
-  i64 iKey;      /* The rowid we are to seek to */
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  assert( pOp->p2!=0 );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  assert( pC->pseudoTableReg==0 );
-  if( pC->pCursor!=0 ){
-    oc = pOp->opcode;
-    pC->nullRow = 0;
-    if( pC->isTable ){
-      /* The input value in P3 might be of any type: integer, real, string,
-      ** blob, or NULL.  But it needs to be an integer before we can do
-      ** the seek, so covert it. */
-      applyNumericAffinity(pIn3);
-      iKey = sqlite3VdbeIntValue(pIn3);
-      pC->rowidIsValid = 0;
-
-      /* If the P3 value could not be converted into an integer without
-      ** loss of information, then special processing is required... */
-      if( (pIn3->flags & MEM_Int)==0 ){
-        if( (pIn3->flags & MEM_Real)==0 ){
-          /* If the P3 value cannot be converted into any kind of a number,
-          ** then the seek is not possible, so jump to P2 */
-          pc = pOp->p2 - 1;
-          break;
-        }
-        /* If we reach this point, then the P3 value must be a floating
-        ** point number. */
-        assert( (pIn3->flags & MEM_Real)!=0 );
-
-        if( iKey==SMALLEST_INT64 && (pIn3->r<(double)iKey || pIn3->r>0) ){
-          /* The P3 value is too large in magnitude to be expressed as an
-          ** integer. */
-          res = 1;
-          if( pIn3->r<0 ){
-            if( oc==OP_SeekGt || oc==OP_SeekGe ){
-              rc = sqlite3BtreeFirst(pC->pCursor, &res);
-              if( rc!=SQLITE_OK ) goto abort_due_to_error;
-            }
-          }else{
-            if( oc==OP_SeekLt || oc==OP_SeekLe ){
-              rc = sqlite3BtreeLast(pC->pCursor, &res);
-              if( rc!=SQLITE_OK ) goto abort_due_to_error;
-            }
-          }
-          if( res ){
-            pc = pOp->p2 - 1;
-          }
-          break;
-        }else if( oc==OP_SeekLt || oc==OP_SeekGe ){
-          /* Use the ceiling() function to convert real->int */
-          if( pIn3->r > (double)iKey ) iKey++;
-        }else{
-          /* Use the floor() function to convert real->int */
-          assert( oc==OP_SeekLe || oc==OP_SeekGt );
-          if( pIn3->r < (double)iKey ) iKey--;
-        }
-      } 
-      rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)iKey, 0, &res);
-      if( rc!=SQLITE_OK ){
-        goto abort_due_to_error;
-      }
-      if( res==0 ){
-        pC->rowidIsValid = 1;
-        pC->lastRowid = iKey;
-      }
-    }else{
-      nField = pOp->p4.i;
-      assert( pOp->p4type==P4_INT32 );
-      assert( nField>0 );
-      r.pKeyInfo = pC->pKeyInfo;
-      r.nField = (u16)nField;
-      if( oc==OP_SeekGt || oc==OP_SeekLe ){
-        r.flags = UNPACKED_INCRKEY;
-      }else{
-        r.flags = 0;
-      }
-      r.aMem = &p->aMem[pOp->p3];
-      rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, &r, 0, 0, &res);
-      if( rc!=SQLITE_OK ){
-        goto abort_due_to_error;
-      }
-      pC->rowidIsValid = 0;
-    }
-    pC->deferredMoveto = 0;
-    pC->cacheStatus = CACHE_STALE;
-#ifdef SQLITE_TEST
-    sqlite3_search_count++;
-#endif
-    if( oc==OP_SeekGe || oc==OP_SeekGt ){
-      if( res<0 || (res==0 && oc==OP_SeekGt) ){
-        rc = sqlite3BtreeNext(pC->pCursor, &res);
-        if( rc!=SQLITE_OK ) goto abort_due_to_error;
-        pC->rowidIsValid = 0;
-      }else{
-        res = 0;
-      }
-    }else{
-      assert( oc==OP_SeekLt || oc==OP_SeekLe );
-      if( res>0 || (res==0 && oc==OP_SeekLt) ){
-        rc = sqlite3BtreePrevious(pC->pCursor, &res);
-        if( rc!=SQLITE_OK ) goto abort_due_to_error;
-        pC->rowidIsValid = 0;
-      }else{
-        /* res might be negative because the table is empty.  Check to
-        ** see if this is the case.
-        */
-        res = sqlite3BtreeEof(pC->pCursor);
-      }
-    }
-    assert( pOp->p2>0 );
-    if( res ){
-      pc = pOp->p2 - 1;
-    }
-  }else{
-    /* This happens when attempting to open the sqlite3_master table
-    ** for read access returns SQLITE_EMPTY. In this case always
-    ** take the jump (since there are no records in the table).
-    */
-    pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: Seek P1 P2 * * *
-**
-** P1 is an open table cursor and P2 is a rowid integer.  Arrange
-** for P1 to move so that it points to the rowid given by P2.
-**
-** This is actually a deferred seek.  Nothing actually happens until
-** the cursor is used to read a record.  That way, if no reads
-** occur, no unnecessary I/O happens.
-*/
-case OP_Seek: {    /* in2 */
-  VdbeCursor *pC;
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  if( ALWAYS(pC->pCursor!=0) ){
-    assert( pC->isTable );
-    pC->nullRow = 0;
-    pC->movetoTarget = sqlite3VdbeIntValue(pIn2);
-    pC->rowidIsValid = 0;
-    pC->deferredMoveto = 1;
-  }
-  break;
-}
-  
-
-/* Opcode: Found P1 P2 P3 * *
-**
-** Register P3 holds a blob constructed by MakeRecord.  P1 is an index.
-** If an entry that matches the value in register p3 exists in P1 then
-** jump to P2.  If the P3 value does not match any entry in P1
-** then fall thru.  The P1 cursor is left pointing at the matching entry
-** if it exists.
-**
-** This instruction is used to implement the IN operator where the
-** left-hand side is a SELECT statement.  P1 may be a true index, or it
-** may be a temporary index that holds the results of the SELECT
-** statement.   This instruction is also used to implement the
-** DISTINCT keyword in SELECT statements.
-**
-** This instruction checks if index P1 contains a record for which 
-** the first N serialized values exactly match the N serialized values
-** in the record in register P3, where N is the total number of values in
-** the P3 record (the P3 record is a prefix of the P1 record). 
-**
-** See also: NotFound, IsUnique, NotExists
-*/
-/* Opcode: NotFound P1 P2 P3 * *
-**
-** Register P3 holds a blob constructed by MakeRecord.  P1 is
-** an index.  If no entry exists in P1 that matches the blob then jump
-** to P2.  If an entry does existing, fall through.  The cursor is left
-** pointing to the entry that matches.
-**
-** See also: Found, NotExists, IsUnique
-*/
-case OP_NotFound:       /* jump, in3 */
-case OP_Found: {        /* jump, in3 */
-  int alreadyExists;
-  VdbeCursor *pC;
-  int res;
-  UnpackedRecord *pIdxKey;
-  char aTempRec[ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*3 + 7];
-
-  alreadyExists = 0;
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  if( ALWAYS(pC->pCursor!=0) ){
-
-    assert( pC->isTable==0 );
-    assert( pIn3->flags & MEM_Blob );
-    ExpandBlob(pIn3);
-    pIdxKey = sqlite3VdbeRecordUnpack(pC->pKeyInfo, pIn3->n, pIn3->z,
-                                      aTempRec, sizeof(aTempRec));
-    if( pIdxKey==0 ){
-      goto no_mem;
-    }
-    if( pOp->opcode==OP_Found ){
-      pIdxKey->flags |= UNPACKED_PREFIX_MATCH;
-    }
-    rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, pIdxKey, 0, 0, &res);
-    sqlite3VdbeDeleteUnpackedRecord(pIdxKey);
-    if( rc!=SQLITE_OK ){
-      break;
-    }
-    alreadyExists = (res==0);
-    pC->deferredMoveto = 0;
-    pC->cacheStatus = CACHE_STALE;
-  }
-  if( pOp->opcode==OP_Found ){
-    if( alreadyExists ) pc = pOp->p2 - 1;
-  }else{
-    if( !alreadyExists ) pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: IsUnique P1 P2 P3 P4 *
-**
-** Cursor P1 is open on an index.  So it has no data and its key consists 
-** of a record generated by OP_MakeRecord where the last field is the 
-** rowid of the entry that the index refers to.
-**
-** The P3 register contains an integer record number. Call this record 
-** number R. Register P4 is the first in a set of N contiguous registers
-** that make up an unpacked index key that can be used with cursor P1.
-** The value of N can be inferred from the cursor. N includes the rowid
-** value appended to the end of the index record. This rowid value may
-** or may not be the same as R.
-**
-** If any of the N registers beginning with register P4 contains a NULL
-** value, jump immediately to P2.
-**
-** Otherwise, this instruction checks if cursor P1 contains an entry
-** where the first (N-1) fields match but the rowid value at the end
-** of the index entry is not R. If there is no such entry, control jumps
-** to instruction P2. Otherwise, the rowid of the conflicting index
-** entry is copied to register P3 and control falls through to the next
-** instruction.
-**
-** See also: NotFound, NotExists, Found
-*/
-case OP_IsUnique: {        /* jump, in3 */
-  u16 ii;
-  VdbeCursor *pCx;
-  BtCursor *pCrsr;
-  u16 nField;
-  Mem *aMem;
-  UnpackedRecord r;                  /* B-Tree index search key */
-  i64 R;                             /* Rowid stored in register P3 */
-
-  aMem = &p->aMem[pOp->p4.i];
-  /* Assert that the values of parameters P1 and P4 are in range. */
-  assert( pOp->p4type==P4_INT32 );
-  assert( pOp->p4.i>0 && pOp->p4.i<=p->nMem );
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-
-  /* Find the index cursor. */
-  pCx = p->apCsr[pOp->p1];
-  assert( pCx->deferredMoveto==0 );
-  pCx->seekResult = 0;
-  pCx->cacheStatus = CACHE_STALE;
-  pCrsr = pCx->pCursor;
-
-  /* If any of the values are NULL, take the jump. */
-  nField = pCx->pKeyInfo->nField;
-  for(ii=0; ii<nField; ii++){
-    if( aMem[ii].flags & MEM_Null ){
-      pc = pOp->p2 - 1;
-      pCrsr = 0;
-      break;
-    }
-  }
-  assert( (aMem[nField].flags & MEM_Null)==0 );
-
-  if( pCrsr!=0 ){
-    /* Populate the index search key. */
-    r.pKeyInfo = pCx->pKeyInfo;
-    r.nField = nField + 1;
-    r.flags = UNPACKED_PREFIX_SEARCH;
-    r.aMem = aMem;
-
-    /* Extract the value of R from register P3. */
-    sqlite3VdbeMemIntegerify(pIn3);
-    R = pIn3->u.i;
-
-    /* Search the B-Tree index. If no conflicting record is found, jump
-    ** to P2. Otherwise, copy the rowid of the conflicting record to
-    ** register P3 and fall through to the next instruction.  */
-    rc = sqlite3BtreeMovetoUnpacked(pCrsr, &r, 0, 0, &pCx->seekResult);
-    if( (r.flags & UNPACKED_PREFIX_SEARCH) || r.rowid==R ){
-      pc = pOp->p2 - 1;
-    }else{
-      pIn3->u.i = r.rowid;
-    }
-  }
-  break;
-}
-
-/* Opcode: NotExists P1 P2 P3 * *
-**
-** Use the content of register P3 as a integer key.  If a record 
-** with that key does not exist in table of P1, then jump to P2. 
-** If the record does exist, then fall thru.  The cursor is left 
-** pointing to the record if it exists.
-**
-** The difference between this operation and NotFound is that this
-** operation assumes the key is an integer and that P1 is a table whereas
-** NotFound assumes key is a blob constructed from MakeRecord and
-** P1 is an index.
-**
-** See also: Found, NotFound, IsUnique
-*/
-case OP_NotExists: {        /* jump, in3 */
-  VdbeCursor *pC;
-  BtCursor *pCrsr;
-  int res;
-  u64 iKey;
-
-  assert( pIn3->flags & MEM_Int );
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  assert( pC->isTable );
-  assert( pC->pseudoTableReg==0 );
-  pCrsr = pC->pCursor;
-  if( pCrsr!=0 ){
-    res = 0;
-    iKey = pIn3->u.i;
-    rc = sqlite3BtreeMovetoUnpacked(pCrsr, 0, iKey, 0, &res);
-    pC->lastRowid = pIn3->u.i;
-    pC->rowidIsValid = res==0 ?1:0;
-    pC->nullRow = 0;
-    pC->cacheStatus = CACHE_STALE;
-    pC->deferredMoveto = 0;
-    if( res!=0 ){
-      pc = pOp->p2 - 1;
-      assert( pC->rowidIsValid==0 );
-    }
-    pC->seekResult = res;
-  }else{
-    /* This happens when an attempt to open a read cursor on the 
-    ** sqlite_master table returns SQLITE_EMPTY.
-    */
-    pc = pOp->p2 - 1;
-    assert( pC->rowidIsValid==0 );
-    pC->seekResult = 0;
-  }
-  break;
-}
-
-/* Opcode: Sequence P1 P2 * * *
-**
-** Find the next available sequence number for cursor P1.
-** Write the sequence number into register P2.
-** The sequence number on the cursor is incremented after this
-** instruction.  
-*/
-case OP_Sequence: {           /* out2-prerelease */
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  assert( p->apCsr[pOp->p1]!=0 );
-  pOut->u.i = p->apCsr[pOp->p1]->seqCount++;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
-}
-
-
-/* Opcode: NewRowid P1 P2 P3 * *
-**
-** Get a new integer record number (a.k.a "rowid") used as the key to a table.
-** The record number is not previously used as a key in the database
-** table that cursor P1 points to.  The new record number is written
-** written to register P2.
-**
-** If P3>0 then P3 is a register in the root frame of this VDBE that holds 
-** the largest previously generated record number. No new record numbers are
-** allowed to be less than this value. When this value reaches its maximum, 
-** a SQLITE_FULL error is generated. The P3 register is updated with the '
-** generated record number. This P3 mechanism is used to help implement the
-** AUTOINCREMENT feature.
-*/
-case OP_NewRowid: {           /* out2-prerelease */
-  i64 v;                 /* The new rowid */
-  VdbeCursor *pC;        /* Cursor of table to get the new rowid */
-  int res;               /* Result of an sqlite3BtreeLast() */
-  int cnt;               /* Counter to limit the number of searches */
-  Mem *pMem;             /* Register holding largest rowid for AUTOINCREMENT */
-  VdbeFrame *pFrame;     /* Root frame of VDBE */
-
-  v = 0;
-  res = 0;
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  if( NEVER(pC->pCursor==0) ){
-    /* The zero initialization above is all that is needed */
-  }else{
-    /* The next rowid or record number (different terms for the same
-    ** thing) is obtained in a two-step algorithm.
-    **
-    ** First we attempt to find the largest existing rowid and add one
-    ** to that.  But if the largest existing rowid is already the maximum
-    ** positive integer, we have to fall through to the second
-    ** probabilistic algorithm
-    **
-    ** The second algorithm is to select a rowid at random and see if
-    ** it already exists in the table.  If it does not exist, we have
-    ** succeeded.  If the random rowid does exist, we select a new one
-    ** and try again, up to 100 times.
-    */
-    assert( pC->isTable );
-    cnt = 0;
-
-#ifdef SQLITE_32BIT_ROWID
-#   define MAX_ROWID 0x7fffffff
-#else
-    /* Some compilers complain about constants of the form 0x7fffffffffffffff.
-    ** Others complain about 0x7ffffffffffffffffLL.  The following macro seems
-    ** to provide the constant while making all compilers happy.
-    */
-#   define MAX_ROWID  (i64)( (((u64)0x7fffffff)<<32) | (u64)0xffffffff )
-#endif
-
-    if( !pC->useRandomRowid ){
-      v = sqlite3BtreeGetCachedRowid(pC->pCursor);
-      if( v==0 ){
-        rc = sqlite3BtreeLast(pC->pCursor, &res);
-        if( rc!=SQLITE_OK ){
-          goto abort_due_to_error;
-        }
-        if( res ){
-          v = 1;
-        }else{
-          assert( sqlite3BtreeCursorIsValid(pC->pCursor) );
-          rc = sqlite3BtreeKeySize(pC->pCursor, &v);
-          assert( rc==SQLITE_OK );   /* Cannot fail following BtreeLast() */
-          if( v==MAX_ROWID ){
-            pC->useRandomRowid = 1;
-          }else{
-            v++;
-          }
-        }
-      }
-
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-      if( pOp->p3 ){
-        /* Assert that P3 is a valid memory cell. */
-        assert( pOp->p3>0 );
-        if( p->pFrame ){
-          for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
-          /* Assert that P3 is a valid memory cell. */
-          assert( pOp->p3<=pFrame->nMem );
-          pMem = &pFrame->aMem[pOp->p3];
-        }else{
-          /* Assert that P3 is a valid memory cell. */
-          assert( pOp->p3<=p->nMem );
-          pMem = &p->aMem[pOp->p3];
-        }
-
-        REGISTER_TRACE(pOp->p3, pMem);
-        sqlite3VdbeMemIntegerify(pMem);
-        assert( (pMem->flags & MEM_Int)!=0 );  /* mem(P3) holds an integer */
-        if( pMem->u.i==MAX_ROWID || pC->useRandomRowid ){
-          rc = SQLITE_FULL;
-          goto abort_due_to_error;
-        }
-        if( v<pMem->u.i+1 ){
-          v = pMem->u.i + 1;
-        }
-        pMem->u.i = v;
-      }
-#endif
-
-      sqlite3BtreeSetCachedRowid(pC->pCursor, v<MAX_ROWID ? v+1 : 0);
-    }
-    if( pC->useRandomRowid ){
-      assert( pOp->p3==0 );  /* We cannot be in random rowid mode if this is
-                             ** an AUTOINCREMENT table. */
-      v = db->lastRowid;
-      cnt = 0;
-      do{
-        if( cnt==0 && (v&0xffffff)==v ){
-          v++;
-        }else{
-          sqlite3_randomness(sizeof(v), &v);
-          if( cnt<5 ) v &= 0xffffff;
-        }
-        rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)v, 0, &res);
-        cnt++;
-      }while( cnt<100 && rc==SQLITE_OK && res==0 );
-      if( rc==SQLITE_OK && res==0 ){
-        rc = SQLITE_FULL;
-        goto abort_due_to_error;
-      }
-    }
-    pC->rowidIsValid = 0;
-    pC->deferredMoveto = 0;
-    pC->cacheStatus = CACHE_STALE;
-  }
-  MemSetTypeFlag(pOut, MEM_Int);
-  pOut->u.i = v;
-  break;
-}
-
-/* Opcode: Insert P1 P2 P3 P4 P5
-**
-** Write an entry into the table of cursor P1.  A new entry is
-** created if it doesn't already exist or the data for an existing
-** entry is overwritten.  The data is the value MEM_Blob stored in register
-** number P2. The key is stored in register P3. The key must
-** be a MEM_Int.
-**
-** If the OPFLAG_NCHANGE flag of P5 is set, then the row change count is
-** incremented (otherwise not).  If the OPFLAG_LASTROWID flag of P5 is set,
-** then rowid is stored for subsequent return by the
-** sqlite3_last_insert_rowid() function (otherwise it is unmodified).
-**
-** If the OPFLAG_USESEEKRESULT flag of P5 is set and if the result of
-** the last seek operation (OP_NotExists) was a success, then this
-** operation will not attempt to find the appropriate row before doing
-** the insert but will instead overwrite the row that the cursor is
-** currently pointing to.  Presumably, the prior OP_NotExists opcode
-** has already positioned the cursor correctly.  This is an optimization
-** that boosts performance by avoiding redundant seeks.
-**
-** If the OPFLAG_ISUPDATE flag is set, then this opcode is part of an
-** UPDATE operation.  Otherwise (if the flag is clear) then this opcode
-** is part of an INSERT operation.  The difference is only important to
-** the update hook.
-**
-** Parameter P4 may point to a string containing the table-name, or
-** may be NULL. If it is not NULL, then the update-hook 
-** (sqlite3.xUpdateCallback) is invoked following a successful insert.
-**
-** (WARNING/TODO: If P1 is a pseudo-cursor and P2 is dynamically
-** allocated, then ownership of P2 is transferred to the pseudo-cursor
-** and register P2 becomes ephemeral.  If the cursor is changed, the
-** 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.
-*/
-case OP_Insert: {
-  Mem *pData;       /* MEM cell holding data for the record to be inserted */
-  Mem *pKey;        /* MEM cell holding key  for the record */
-  i64 iKey;         /* The integer ROWID or key for the record to be inserted */
-  VdbeCursor *pC;   /* Cursor to table into which insert is written */
-  int nZero;        /* Number of zero-bytes to append */
-  int seekResult;   /* Result of prior seek or 0 if no USESEEKRESULT flag */
-  const char *zDb;  /* database name - used by the update hook */
-  const char *zTbl; /* Table name - used by the opdate hook */
-  int op;           /* Opcode for update hook: SQLITE_UPDATE or SQLITE_INSERT */
-
-  pData = &p->aMem[pOp->p2];
-  pKey = &p->aMem[pOp->p3];
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  assert( pC->pCursor!=0 );
-  assert( pC->pseudoTableReg==0 );
-  assert( pKey->flags & MEM_Int );
-  assert( pC->isTable );
-  REGISTER_TRACE(pOp->p2, pData);
-  REGISTER_TRACE(pOp->p3, pKey);
-
-  iKey = pKey->u.i;
-  if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++;
-  if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = pKey->u.i;
-  if( pData->flags & MEM_Null ){
-    pData->z = 0;
-    pData->n = 0;
-  }else{
-    assert( pData->flags & (MEM_Blob|MEM_Str) );
-  }
-  seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? pC->seekResult : 0);
-  if( pData->flags & MEM_Zero ){
-    nZero = pData->u.nZero;
-  }else{
-    nZero = 0;
-  }
-  sqlite3BtreeSetCachedRowid(pC->pCursor, 0);
-  rc = sqlite3BtreeInsert(pC->pCursor, 0, iKey,
-                          pData->z, pData->n, nZero,
-                          pOp->p5 & OPFLAG_APPEND, seekResult
-  );
-  pC->rowidIsValid = 0;
-  pC->deferredMoveto = 0;
-  pC->cacheStatus = CACHE_STALE;
-
-  /* Invoke the update-hook if required. */
-  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
-    zDb = db->aDb[pC->iDb].zName;
-    zTbl = pOp->p4.z;
-    op = ((pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT);
-    assert( pC->isTable );
-    db->xUpdateCallback(db->pUpdateArg, op, zDb, zTbl, iKey);
-    assert( pC->iDb>=0 );
-  }
-  break;
-}
-
-/* Opcode: Delete P1 P2 * P4 *
-**
-** Delete the record at which the P1 cursor is currently pointing.
-**
-** The cursor will be left pointing at either the next or the previous
-** record in the table. If it is left pointing at the next record, then
-** the next Next instruction will be a no-op.  Hence it is OK to delete
-** a record from within an Next loop.
-**
-** If the OPFLAG_NCHANGE flag of P2 is set, then the row change count is
-** incremented (otherwise not).
-**
-** P1 must not be pseudo-table.  It has to be a real table with
-** multiple rows.
-**
-** If P4 is not NULL, then it is the name of the table that P1 is
-** pointing to.  The update hook will be invoked, if it exists.
-** If P4 is not NULL then the P1 cursor must have been positioned
-** using OP_NotFound prior to invoking this opcode.
-*/
-case OP_Delete: {
-  i64 iKey;
-  VdbeCursor *pC;
-
-  iKey = 0;
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  assert( pC->pCursor!=0 );  /* Only valid for real tables, no pseudotables */
-
-  /* If the update-hook will be invoked, set iKey to the rowid of the
-  ** row being deleted.
-  */
-  if( db->xUpdateCallback && pOp->p4.z ){
-    assert( pC->isTable );
-    assert( pC->rowidIsValid );  /* lastRowid set by previous OP_NotFound */
-    iKey = pC->lastRowid;
-  }
-
-  /* The OP_Delete opcode always follows an OP_NotExists or OP_Last or
-  ** OP_Column on the same table without any intervening operations that
-  ** might move or invalidate the cursor.  Hence cursor pC is always pointing
-  ** to the row to be deleted and the sqlite3VdbeCursorMoveto() operation
-  ** below is always a no-op and cannot fail.  We will run it anyhow, though,
-  ** to guard against future changes to the code generator.
-  **/
-  assert( pC->deferredMoveto==0 );
-  rc = sqlite3VdbeCursorMoveto(pC);
-  if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;
-
-  sqlite3BtreeSetCachedRowid(pC->pCursor, 0);
-  rc = sqlite3BtreeDelete(pC->pCursor);
-  pC->cacheStatus = CACHE_STALE;
-
-  /* Invoke the update-hook if required. */
-  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
-    const char *zDb = db->aDb[pC->iDb].zName;
-    const char *zTbl = pOp->p4.z;
-    db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, zDb, zTbl, iKey);
-    assert( pC->iDb>=0 );
-  }
-  if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
-  break;
-}
-/* Opcode: ResetCount * * * * *
-**
-** The value of the change counter is copied to the database handle
-** change counter (returned by subsequent calls to sqlite3_changes()).
-** Then the VMs internal change counter resets to 0.
-** This is used by trigger programs.
-*/
-case OP_ResetCount: {
-  sqlite3VdbeSetChanges(db, p->nChange);
-  p->nChange = 0;
-  break;
-}
-
-/* Opcode: RowData P1 P2 * * *
-**
-** Write into register P2 the complete row data for cursor P1.
-** There is no interpretation of the data.  
-** It is just copied onto the P2 register exactly as 
-** it is found in the database file.
-**
-** If the P1 cursor must be pointing to a valid row (not a NULL row)
-** of a real table, not a pseudo-table.
-*/
-/* Opcode: RowKey P1 P2 * * *
-**
-** Write into register P2 the complete row key for cursor P1.
-** There is no interpretation of the data.  
-** The key is copied onto the P3 register exactly as 
-** it is found in the database file.
-**
-** If the P1 cursor must be pointing to a valid row (not a NULL row)
-** of a real table, not a pseudo-table.
-*/
-case OP_RowKey:
-case OP_RowData: {
-  VdbeCursor *pC;
-  BtCursor *pCrsr;
-  u32 n;
-  i64 n64;
-
-  pOut = &p->aMem[pOp->p2];
-
-  /* Note that RowKey and RowData are really exactly the same instruction */
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC->isTable || pOp->opcode==OP_RowKey );
-  assert( pC->isIndex || pOp->opcode==OP_RowData );
-  assert( pC!=0 );
-  assert( pC->nullRow==0 );
-  assert( pC->pseudoTableReg==0 );
-  assert( pC->pCursor!=0 );
-  pCrsr = pC->pCursor;
-  assert( sqlite3BtreeCursorIsValid(pCrsr) );
-
-  /* The OP_RowKey and OP_RowData opcodes always follow OP_NotExists or
-  ** OP_Rewind/Op_Next with no intervening instructions that might invalidate
-  ** the cursor.  Hence the following sqlite3VdbeCursorMoveto() call is always
-  ** a no-op and can never fail.  But we leave it in place as a safety.
-  */
-  assert( pC->deferredMoveto==0 );
-  rc = sqlite3VdbeCursorMoveto(pC);
-  if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;
-
-  if( pC->isIndex ){
-    assert( !pC->isTable );
-    rc = sqlite3BtreeKeySize(pCrsr, &n64);
-    assert( rc==SQLITE_OK );    /* True because of CursorMoveto() call above */
-    if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
-      goto too_big;
-    }
-    n = (u32)n64;
-  }else{
-    rc = sqlite3BtreeDataSize(pCrsr, &n);
-    assert( rc==SQLITE_OK );    /* DataSize() cannot fail */
-    if( n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
-      goto too_big;
-    }
-  }
-  if( sqlite3VdbeMemGrow(pOut, n, 0) ){
-    goto no_mem;
-  }
-  pOut->n = n;
-  MemSetTypeFlag(pOut, MEM_Blob);
-  if( pC->isIndex ){
-    rc = sqlite3BtreeKey(pCrsr, 0, n, pOut->z);
-  }else{
-    rc = sqlite3BtreeData(pCrsr, 0, n, pOut->z);
-  }
-  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
-  UPDATE_MAX_BLOBSIZE(pOut);
-  break;
-}
-
-/* Opcode: Rowid P1 P2 * * *
-**
-** Store in register P2 an integer which is the key of the table entry that
-** P1 is currently point to.
-**
-** P1 can be either an ordinary table or a virtual table.  There used to
-** be a separate OP_VRowid opcode for use with virtual tables, but this
-** one opcode now works for both table types.
-*/
-case OP_Rowid: {                 /* out2-prerelease */
-  VdbeCursor *pC;
-  i64 v;
-  sqlite3_vtab *pVtab;
-  const sqlite3_module *pModule;
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  assert( pC->pseudoTableReg==0 );
-  if( pC->nullRow ){
-    /* Do nothing so that reg[P2] remains NULL */
-    break;
-  }else if( pC->deferredMoveto ){
-    v = pC->movetoTarget;
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  }else if( pC->pVtabCursor ){
-    pVtab = pC->pVtabCursor->pVtab;
-    pModule = pVtab->pModule;
-    assert( pModule->xRowid );
-    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-    rc = pModule->xRowid(pC->pVtabCursor, &v);
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = pVtab->zErrMsg;
-    pVtab->zErrMsg = 0;
-    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-  }else{
-    assert( pC->pCursor!=0 );
-    rc = sqlite3VdbeCursorMoveto(pC);
-    if( rc ) goto abort_due_to_error;
-    if( pC->rowidIsValid ){
-      v = pC->lastRowid;
-    }else{
-      rc = sqlite3BtreeKeySize(pC->pCursor, &v);
-      assert( rc==SQLITE_OK );  /* Always so because of CursorMoveto() above */
-    }
-  }
-  pOut->u.i = v;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
-}
-
-/* Opcode: NullRow P1 * * * *
-**
-** Move the cursor P1 to a null row.  Any OP_Column operations
-** that occur while the cursor is on the null row will always
-** write a NULL.
-*/
-case OP_NullRow: {
-  VdbeCursor *pC;
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  pC->nullRow = 1;
-  pC->rowidIsValid = 0;
-  if( pC->pCursor ){
-    sqlite3BtreeClearCursor(pC->pCursor);
-  }
-  break;
-}
-
-/* Opcode: Last P1 P2 * * *
-**
-** The next use of the Rowid or Column or Next instruction for P1 
-** will refer to the last entry in the database table or index.
-** If the table or index is empty and P2>0, then jump immediately to P2.
-** If P2 is 0 or if the table or index is not empty, fall through
-** to the following instruction.
-*/
-case OP_Last: {        /* jump */
-  VdbeCursor *pC;
-  BtCursor *pCrsr;
-  int res;
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  pCrsr = pC->pCursor;
-  if( pCrsr==0 ){
-    res = 1;
-  }else{
-    rc = sqlite3BtreeLast(pCrsr, &res);
-  }
-  pC->nullRow = (u8)res;
-  pC->deferredMoveto = 0;
-  pC->rowidIsValid = 0;
-  pC->cacheStatus = CACHE_STALE;
-  if( pOp->p2>0 && res ){
-    pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-
-/* Opcode: Sort P1 P2 * * *
-**
-** This opcode does exactly the same thing as OP_Rewind except that
-** it increments an undocumented global variable used for testing.
-**
-** Sorting is accomplished by writing records into a sorting index,
-** then rewinding that index and playing it back from beginning to
-** end.  We use the OP_Sort opcode instead of OP_Rewind to do the
-** rewinding so that the global variable will be incremented and
-** regression tests can determine whether or not the optimizer is
-** correctly optimizing out sorts.
-*/
-case OP_Sort: {        /* jump */
-#ifdef SQLITE_TEST
-  sqlite3_sort_count++;
-  sqlite3_search_count--;
-#endif
-  p->aCounter[SQLITE_STMTSTATUS_SORT-1]++;
-  /* Fall through into OP_Rewind */
-}
-/* Opcode: Rewind P1 P2 * * *
-**
-** The next use of the Rowid or Column or Next instruction for P1 
-** will refer to the first entry in the database table or index.
-** If the table or index is empty and P2>0, then jump immediately to P2.
-** If P2 is 0 or if the table or index is not empty, fall through
-** to the following instruction.
-*/
-case OP_Rewind: {        /* jump */
-  VdbeCursor *pC;
-  BtCursor *pCrsr;
-  int res;
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  if( (pCrsr = pC->pCursor)!=0 ){
-    rc = sqlite3BtreeFirst(pCrsr, &res);
-    pC->atFirst = res==0 ?1:0;
-    pC->deferredMoveto = 0;
-    pC->cacheStatus = CACHE_STALE;
-    pC->rowidIsValid = 0;
-  }else{
-    res = 1;
-  }
-  pC->nullRow = (u8)res;
-  assert( pOp->p2>0 && pOp->p2<p->nOp );
-  if( res ){
-    pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: Next P1 P2 * * *
-**
-** Advance cursor P1 so that it points to the next key/data pair in its
-** table or index.  If there are no more key/value pairs then fall through
-** to the following instruction.  But if the cursor advance was successful,
-** jump immediately to P2.
-**
-** The P1 cursor must be for a real table, not a pseudo-table.
-**
-** See also: Prev
-*/
-/* Opcode: Prev P1 P2 * * *
-**
-** Back up cursor P1 so that it points to the previous key/data pair in its
-** table or index.  If there is no previous key/value pairs then fall through
-** to the following instruction.  But if the cursor backup was successful,
-** jump immediately to P2.
-**
-** The P1 cursor must be for a real table, not a pseudo-table.
-*/
-case OP_Prev:          /* jump */
-case OP_Next: {        /* jump */
-  VdbeCursor *pC;
-  BtCursor *pCrsr;
-  int res;
-
-  CHECK_FOR_INTERRUPT;
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  if( pC==0 ){
-    break;  /* See ticket #2273 */
-  }
-  pCrsr = pC->pCursor;
-  if( pCrsr==0 ){
-    pC->nullRow = 1;
-    break;
-  }
-  res = 1;
-  assert( pC->deferredMoveto==0 );
-  rc = pOp->opcode==OP_Next ? sqlite3BtreeNext(pCrsr, &res) :
-                              sqlite3BtreePrevious(pCrsr, &res);
-  pC->nullRow = (u8)res;
-  pC->cacheStatus = CACHE_STALE;
-  if( res==0 ){
-    pc = pOp->p2 - 1;
-    if( pOp->p5 ) p->aCounter[pOp->p5-1]++;
-#ifdef SQLITE_TEST
-    sqlite3_search_count++;
-#endif
-  }
-  pC->rowidIsValid = 0;
-  break;
-}
-
-/* Opcode: IdxInsert P1 P2 P3 * P5
-**
-** Register P2 holds a SQL index key made using the
-** MakeRecord instructions.  This opcode writes that key
-** into the index P1.  Data for the entry is nil.
-**
-** P3 is a flag that provides a hint to the b-tree layer that this
-** insert is likely to be an append.
-**
-** This instruction only works for indices.  The equivalent instruction
-** for tables is OP_Insert.
-*/
-case OP_IdxInsert: {        /* in2 */
-  VdbeCursor *pC;
-  BtCursor *pCrsr;
-  int nKey;
-  const char *zKey;
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  assert( pIn2->flags & MEM_Blob );
-  pCrsr = pC->pCursor;
-  if( ALWAYS(pCrsr!=0) ){
-    assert( pC->isTable==0 );
-    rc = ExpandBlob(pIn2);
-    if( rc==SQLITE_OK ){
-      nKey = pIn2->n;
-      zKey = pIn2->z;
-      rc = sqlite3BtreeInsert(pCrsr, zKey, nKey, "", 0, 0, pOp->p3, 
-          ((pOp->p5 & OPFLAG_USESEEKRESULT) ? pC->seekResult : 0)
-      );
-      assert( pC->deferredMoveto==0 );
-      pC->cacheStatus = CACHE_STALE;
-    }
-  }
-  break;
-}
-
-/* Opcode: IdxDelete P1 P2 P3 * *
-**
-** The content of P3 registers starting at register P2 form
-** an unpacked index key. This opcode removes that entry from the 
-** index opened by cursor P1.
-*/
-case OP_IdxDelete: {
-  VdbeCursor *pC;
-  BtCursor *pCrsr;
-  int res;
-  UnpackedRecord r;
-
-  assert( pOp->p3>0 );
-  assert( pOp->p2>0 && pOp->p2+pOp->p3<=p->nMem+1 );
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  pCrsr = pC->pCursor;
-  if( ALWAYS(pCrsr!=0) ){
-    r.pKeyInfo = pC->pKeyInfo;
-    r.nField = (u16)pOp->p3;
-    r.flags = 0;
-    r.aMem = &p->aMem[pOp->p2];
-    rc = sqlite3BtreeMovetoUnpacked(pCrsr, &r, 0, 0, &res);
-    if( rc==SQLITE_OK && res==0 ){
-      rc = sqlite3BtreeDelete(pCrsr);
-    }
-    assert( pC->deferredMoveto==0 );
-    pC->cacheStatus = CACHE_STALE;
-  }
-  break;
-}
-
-/* Opcode: IdxRowid P1 P2 * * *
-**
-** Write into register P2 an integer which is the last entry in the record at
-** the end of the index key pointed to by cursor P1.  This integer should be
-** the rowid of the table entry to which this index entry points.
-**
-** See also: Rowid, MakeRecord.
-*/
-case OP_IdxRowid: {              /* out2-prerelease */
-  BtCursor *pCrsr;
-  VdbeCursor *pC;
-  i64 rowid;
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  pCrsr = pC->pCursor;
-  if( ALWAYS(pCrsr!=0) ){
-    rc = sqlite3VdbeCursorMoveto(pC);
-    if( NEVER(rc) ) goto abort_due_to_error;
-    assert( pC->deferredMoveto==0 );
-    assert( pC->isTable==0 );
-    if( !pC->nullRow ){
-      rc = sqlite3VdbeIdxRowid(db, pCrsr, &rowid);
-      if( rc!=SQLITE_OK ){
-        goto abort_due_to_error;
-      }
-      MemSetTypeFlag(pOut, MEM_Int);
-      pOut->u.i = rowid;
-    }
-  }
-  break;
-}
-
-/* Opcode: IdxGE P1 P2 P3 P4 P5
-**
-** The P4 register values beginning with P3 form an unpacked index 
-** key that omits the ROWID.  Compare this key value against the index 
-** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
-**
-** If the P1 index entry is greater than or equal to the key value
-** then jump to P2.  Otherwise fall through to the next instruction.
-**
-** If P5 is non-zero then the key value is increased by an epsilon 
-** prior to the comparison.  This make the opcode work like IdxGT except
-** that if the key from register P3 is a prefix of the key in the cursor,
-** the result is false whereas it would be true with IdxGT.
-*/
-/* Opcode: IdxLT P1 P2 P3 * P5
-**
-** The P4 register values beginning with P3 form an unpacked index 
-** key that omits the ROWID.  Compare this key value against the index 
-** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
-**
-** If the P1 index entry is less than the key value then jump to P2.
-** Otherwise fall through to the next instruction.
-**
-** If P5 is non-zero then the key value is increased by an epsilon prior 
-** to the comparison.  This makes the opcode work like IdxLE.
-*/
-case OP_IdxLT:          /* jump, in3 */
-case OP_IdxGE: {        /* jump, in3 */
-  VdbeCursor *pC;
-  int res;
-  UnpackedRecord r;
-
-  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  pC = p->apCsr[pOp->p1];
-  assert( pC!=0 );
-  if( ALWAYS(pC->pCursor!=0) ){
-    assert( pC->deferredMoveto==0 );
-    assert( pOp->p5==0 || pOp->p5==1 );
-    assert( pOp->p4type==P4_INT32 );
-    r.pKeyInfo = pC->pKeyInfo;
-    r.nField = (u16)pOp->p4.i;
-    if( pOp->p5 ){
-      r.flags = UNPACKED_INCRKEY | UNPACKED_IGNORE_ROWID;
-    }else{
-      r.flags = UNPACKED_IGNORE_ROWID;
-    }
-    r.aMem = &p->aMem[pOp->p3];
-    rc = sqlite3VdbeIdxKeyCompare(pC, &r, &res);
-    if( pOp->opcode==OP_IdxLT ){
-      res = -res;
-    }else{
-      assert( pOp->opcode==OP_IdxGE );
-      res++;
-    }
-    if( res>0 ){
-      pc = pOp->p2 - 1 ;
-    }
-  }
-  break;
-}
-
-/* Opcode: Destroy P1 P2 P3 * *
-**
-** Delete an entire database table or index whose root page in the database
-** file is given by P1.
-**
-** The table being destroyed is in the main database file if P3==0.  If
-** P3==1 then the table to be clear is in the auxiliary database file
-** that is used to store tables create using CREATE TEMPORARY TABLE.
-**
-** If AUTOVACUUM is enabled then it is possible that another root page
-** might be moved into the newly deleted root page in order to keep all
-** root pages contiguous at the beginning of the database.  The former
-** value of the root page that moved - its value before the move occurred -
-** is stored in register P2.  If no page 
-** movement was required (because the table being dropped was already 
-** the last one in the database) then a zero is stored in register P2.
-** If AUTOVACUUM is disabled then a zero is stored in register P2.
-**
-** See also: Clear
-*/
-case OP_Destroy: {     /* out2-prerelease */
-  int iMoved;
-  int iCnt;
-  Vdbe *pVdbe;
-  int iDb;
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  iCnt = 0;
-  for(pVdbe=db->pVdbe; pVdbe; pVdbe = pVdbe->pNext){
-    if( pVdbe->magic==VDBE_MAGIC_RUN && pVdbe->inVtabMethod<2 && pVdbe->pc>=0 ){
-      iCnt++;
-    }
-  }
-#else
-  iCnt = db->activeVdbeCnt;
-#endif
-  if( iCnt>1 ){
-    rc = SQLITE_LOCKED;
-    p->errorAction = OE_Abort;
-  }else{
-    iDb = pOp->p3;
-    assert( iCnt==1 );
-    assert( (p->btreeMask & (1<<iDb))!=0 );
-    rc = sqlite3BtreeDropTable(db->aDb[iDb].pBt, pOp->p1, &iMoved);
-    MemSetTypeFlag(pOut, MEM_Int);
-    pOut->u.i = iMoved;
-#ifndef SQLITE_OMIT_AUTOVACUUM
-    if( rc==SQLITE_OK && iMoved!=0 ){
-      sqlite3RootPageMoved(&db->aDb[iDb], iMoved, pOp->p1);
-    }
-#endif
-  }
-  break;
-}
-
-/* Opcode: Clear P1 P2 P3
-**
-** Delete all contents of the database table or index whose root page
-** in the database file is given by P1.  But, unlike Destroy, do not
-** remove the table or index from the database file.
-**
-** The table being clear is in the main database file if P2==0.  If
-** P2==1 then the table to be clear is in the auxiliary database file
-** that is used to store tables create using CREATE TEMPORARY TABLE.
-**
-** If the P3 value is non-zero, then the table referred to must be an
-** intkey table (an SQL table, not an index). In this case the row change 
-** count is incremented by the number of rows in the table being cleared. 
-** If P3 is greater than zero, then the value stored in register P3 is
-** also incremented by the number of rows in the table being cleared.
-**
-** See also: Destroy
-*/
-case OP_Clear: {
-  int nChange;
- 
-  nChange = 0;
-  assert( (p->btreeMask & (1<<pOp->p2))!=0 );
-  rc = sqlite3BtreeClearTable(
-      db->aDb[pOp->p2].pBt, pOp->p1, (pOp->p3 ? &nChange : 0)
-  );
-  if( pOp->p3 ){
-    p->nChange += nChange;
-    if( pOp->p3>0 ){
-      p->aMem[pOp->p3].u.i += nChange;
-    }
-  }
-  break;
-}
-
-/* Opcode: CreateTable P1 P2 * * *
-**
-** Allocate a new table in the main database file if P1==0 or in the
-** auxiliary database file if P1==1 or in an attached database if
-** P1>1.  Write the root page number of the new table into
-** register P2
-**
-** The difference between a table and an index is this:  A table must
-** have a 4-byte integer key and can have arbitrary data.  An index
-** has an arbitrary key but no data.
-**
-** See also: CreateIndex
-*/
-/* Opcode: CreateIndex P1 P2 * * *
-**
-** Allocate a new index in the main database file if P1==0 or in the
-** auxiliary database file if P1==1 or in an attached database if
-** P1>1.  Write the root page number of the new table into
-** register P2.
-**
-** See documentation on OP_CreateTable for additional information.
-*/
-case OP_CreateIndex:            /* out2-prerelease */
-case OP_CreateTable: {          /* out2-prerelease */
-  int pgno;
-  int flags;
-  Db *pDb;
-
-  pgno = 0;
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pDb = &db->aDb[pOp->p1];
-  assert( pDb->pBt!=0 );
-  if( pOp->opcode==OP_CreateTable ){
-    /* flags = BTREE_INTKEY; */
-    flags = BTREE_LEAFDATA|BTREE_INTKEY;
-  }else{
-    flags = BTREE_ZERODATA;
-  }
-  rc = sqlite3BtreeCreateTable(pDb->pBt, &pgno, flags);
-  pOut->u.i = pgno;
-  MemSetTypeFlag(pOut, MEM_Int);
-  break;
-}
-
-/* Opcode: ParseSchema P1 P2 * P4 *
-**
-** Read and parse all entries from the SQLITE_MASTER table of database P1
-** that match the WHERE clause P4.  P2 is the "force" flag.   Always do
-** the parsing if P2 is true.  If P2 is false, then this routine is a
-** no-op if the schema is not currently loaded.  In other words, if P2
-** is false, the SQLITE_MASTER table is only parsed if the rest of the
-** schema is already loaded into the symbol table.
-**
-** This opcode invokes the parser to create a new virtual machine,
-** then runs the new virtual machine.  It is thus a re-entrant opcode.
-*/
-case OP_ParseSchema: {
-  int iDb;
-  const char *zMaster;
-  char *zSql;
-  InitData initData;
-
-  iDb = pOp->p1;
-  assert( iDb>=0 && iDb<db->nDb );
-
-  /* If pOp->p2 is 0, then this opcode is being executed to read a
-  ** single row, for example the row corresponding to a new index
-  ** created by this VDBE, from the sqlite_master table. It only
-  ** does this if the corresponding in-memory schema is currently
-  ** loaded. Otherwise, the new index definition can be loaded along
-  ** with the rest of the schema when it is required.
-  **
-  ** Although the mutex on the BtShared object that corresponds to
-  ** database iDb (the database containing the sqlite_master table
-  ** read by this instruction) is currently held, it is necessary to
-  ** obtain the mutexes on all attached databases before checking if
-  ** the schema of iDb is loaded. This is because, at the start of
-  ** the sqlite3_exec() call below, SQLite will invoke 
-  ** sqlite3BtreeEnterAll(). If all mutexes are not already held, the
-  ** iDb mutex may be temporarily released to avoid deadlock. If 
-  ** this happens, then some other thread may delete the in-memory 
-  ** schema of database iDb before the SQL statement runs. The schema
-  ** will not be reloaded becuase the db->init.busy flag is set. This
-  ** can result in a "no such table: sqlite_master" or "malformed
-  ** database schema" error being returned to the user.
-  */
-  assert( sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
-  sqlite3BtreeEnterAll(db);
-  if( pOp->p2 || DbHasProperty(db, iDb, DB_SchemaLoaded) ){
-    zMaster = SCHEMA_TABLE(iDb);
-    initData.db = db;
-    initData.iDb = pOp->p1;
-    initData.pzErrMsg = &p->zErrMsg;
-    zSql = sqlite3MPrintf(db,
-       "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s",
-       db->aDb[iDb].zName, zMaster, pOp->p4.z);
-    if( zSql==0 ){
-      rc = SQLITE_NOMEM;
-    }else{
-      (void)sqlite3SafetyOff(db);
-      assert( db->init.busy==0 );
-      db->init.busy = 1;
-      initData.rc = SQLITE_OK;
-      assert( !db->mallocFailed );
-      rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
-      if( rc==SQLITE_OK ) rc = initData.rc;
-      sqlite3DbFree(db, zSql);
-      db->init.busy = 0;
-      (void)sqlite3SafetyOn(db);
-    }
-  }
-  sqlite3BtreeLeaveAll(db);
-  if( rc==SQLITE_NOMEM ){
-    goto no_mem;
-  }
-  break;  
-}
-
-#if !defined(SQLITE_OMIT_ANALYZE)
-/* Opcode: LoadAnalysis P1 * * * *
-**
-** Read the sqlite_stat1 table for database P1 and load the content
-** of that table into the internal index hash table.  This will cause
-** the analysis to be used when preparing all subsequent queries.
-*/
-case OP_LoadAnalysis: {
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  rc = sqlite3AnalysisLoad(db, pOp->p1);
-  break;  
-}
-#endif /* !defined(SQLITE_OMIT_ANALYZE) */
-
-/* Opcode: DropTable P1 * * P4 *
-**
-** Remove the internal (in-memory) data structures that describe
-** the table named P4 in database P1.  This is called after a table
-** is dropped in order to keep the internal representation of the
-** schema consistent with what is on disk.
-*/
-case OP_DropTable: {
-  sqlite3UnlinkAndDeleteTable(db, pOp->p1, pOp->p4.z);
-  break;
-}
-
-/* Opcode: DropIndex P1 * * P4 *
-**
-** Remove the internal (in-memory) data structures that describe
-** the index named P4 in database P1.  This is called after an index
-** is dropped in order to keep the internal representation of the
-** schema consistent with what is on disk.
-*/
-case OP_DropIndex: {
-  sqlite3UnlinkAndDeleteIndex(db, pOp->p1, pOp->p4.z);
-  break;
-}
-
-/* Opcode: DropTrigger P1 * * P4 *
-**
-** Remove the internal (in-memory) data structures that describe
-** the trigger named P4 in database P1.  This is called after a trigger
-** is dropped in order to keep the internal representation of the
-** schema consistent with what is on disk.
-*/
-case OP_DropTrigger: {
-  sqlite3UnlinkAndDeleteTrigger(db, pOp->p1, pOp->p4.z);
-  break;
-}
-
-
-#ifndef SQLITE_OMIT_INTEGRITY_CHECK
-/* Opcode: IntegrityCk P1 P2 P3 * P5
-**
-** Do an analysis of the currently open database.  Store in
-** register P1 the text of an error message describing any problems.
-** If no problems are found, store a NULL in register P1.
-**
-** The register P3 contains the maximum number of allowed errors.
-** At most reg(P3) errors will be reported.
-** In other words, the analysis stops as soon as reg(P1) errors are 
-** seen.  Reg(P1) is updated with the number of errors remaining.
-**
-** The root page numbers of all tables in the database are integer
-** stored in reg(P1), reg(P1+1), reg(P1+2), ....  There are P2 tables
-** total.
-**
-** If P5 is not zero, the check is done on the auxiliary database
-** file, not the main database file.
-**
-** This opcode is used to implement the integrity_check pragma.
-*/
-case OP_IntegrityCk: {
-  int nRoot;      /* Number of tables to check.  (Number of root pages.) */
-  int *aRoot;     /* Array of rootpage numbers for tables to be checked */
-  int j;          /* Loop counter */
-  int nErr;       /* Number of errors reported */
-  char *z;        /* Text of the error report */
-  Mem *pnErr;     /* Register keeping track of errors remaining */
-  
-  nRoot = pOp->p2;
-  assert( nRoot>0 );
-  aRoot = sqlite3DbMallocRaw(db, sizeof(int)*(nRoot+1) );
-  if( aRoot==0 ) goto no_mem;
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pnErr = &p->aMem[pOp->p3];
-  assert( (pnErr->flags & MEM_Int)!=0 );
-  assert( (pnErr->flags & (MEM_Str|MEM_Blob))==0 );
-  pIn1 = &p->aMem[pOp->p1];
-  for(j=0; j<nRoot; j++){
-    aRoot[j] = (int)sqlite3VdbeIntValue(&pIn1[j]);
-  }
-  aRoot[j] = 0;
-  assert( pOp->p5<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p5))!=0 );
-  z = sqlite3BtreeIntegrityCheck(db->aDb[pOp->p5].pBt, aRoot, nRoot,
-                                 (int)pnErr->u.i, &nErr);
-  sqlite3DbFree(db, aRoot);
-  pnErr->u.i -= nErr;
-  sqlite3VdbeMemSetNull(pIn1);
-  if( nErr==0 ){
-    assert( z==0 );
-  }else if( z==0 ){
-    goto no_mem;
-  }else{
-    sqlite3VdbeMemSetStr(pIn1, z, -1, SQLITE_UTF8, sqlite3_free);
-  }
-  UPDATE_MAX_BLOBSIZE(pIn1);
-  sqlite3VdbeChangeEncoding(pIn1, encoding);
-  break;
-}
-#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
-
-/* Opcode: RowSetAdd P1 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: {       /* in2 */
-  Mem *pIdx;
-  Mem *pVal;
-  assert( pOp->p1>0 && pOp->p1<=p->nMem );
-  pIdx = &p->aMem[pOp->p1];
-  assert( pOp->p2>0 && pOp->p2<=p->nMem );
-  pVal = &p->aMem[pOp->p2];
-  assert( (pVal->flags & MEM_Int)!=0 );
-  if( (pIdx->flags & MEM_RowSet)==0 ){
-    sqlite3VdbeMemSetRowSet(pIdx);
-    if( (pIdx->flags & MEM_RowSet)==0 ) goto no_mem;
-  }
-  sqlite3RowSetInsert(pIdx->u.pRowSet, pVal->u.i);
-  break;
-}
-
-/* Opcode: RowSetRead P1 P2 P3 * *
-**
-** 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, out3 */
-  Mem *pIdx;
-  i64 val;
-  assert( pOp->p1>0 && pOp->p1<=p->nMem );
-  CHECK_FOR_INTERRUPT;
-  pIdx = &p->aMem[pOp->p1];
-  pOut = &p->aMem[pOp->p3];
-  if( (pIdx->flags & MEM_RowSet)==0 
-   || sqlite3RowSetNext(pIdx->u.pRowSet, &val)==0
-  ){
-    /* The boolean index is empty */
-    sqlite3VdbeMemSetNull(pIdx);
-    pc = pOp->p2 - 1;
-  }else{
-    /* A value was pulled from the index */
-    assert( pOp->p3>0 && pOp->p3<=p->nMem );
-    sqlite3VdbeMemSetInt64(pOut, val);
-  }
-  break;
-}
-
-/* Opcode: RowSetTest P1 P2 P3 P4
-**
-** Register P3 is assumed to hold a 64-bit integer value. If register P1
-** contains a RowSet object and that RowSet object contains
-** the value held in P3, jump to register P2. Otherwise, insert the
-** integer in P3 into the RowSet and continue on to the
-** next opcode.
-**
-** The RowSet object is optimized for the case where successive sets
-** of integers, where each set contains no duplicates. Each set
-** of values is identified by a unique P4 value. The first set
-** must have P4==0, the final set P4=-1.  P4 must be either -1 or
-** non-negative.  For non-negative values of P4 only the lower 4
-** bits are significant.
-**
-** This allows optimizations: (a) when P4==0 there is no need to test
-** the rowset object for P3, as it is guaranteed not to contain it,
-** (b) when P4==-1 there is no need to insert the value, as it will
-** never be tested for, and (c) when a value that is part of set X is
-** inserted, there is no need to search to see if the same value was
-** previously inserted as part of set X (only if it was previously
-** inserted as part of some other set).
-*/
-case OP_RowSetTest: {                     /* jump, in1, in3 */
-  int iSet;
-  int exists;
-
-  iSet = pOp->p4.i;
-  assert( pIn3->flags&MEM_Int );
-
-  /* If there is anything other than a rowset object in memory cell P1,
-  ** delete it now and initialize P1 with an empty rowset
-  */
-  if( (pIn1->flags & MEM_RowSet)==0 ){
-    sqlite3VdbeMemSetRowSet(pIn1);
-    if( (pIn1->flags & MEM_RowSet)==0 ) goto no_mem;
-  }
-
-  assert( pOp->p4type==P4_INT32 );
-  assert( iSet==-1 || iSet>=0 );
-  if( iSet ){
-    exists = sqlite3RowSetTest(pIn1->u.pRowSet, 
-                               (u8)(iSet>=0 ? iSet & 0xf : 0xff),
-                               pIn3->u.i);
-    if( exists ){
-      pc = pOp->p2 - 1;
-      break;
-    }
-  }
-  if( iSet>=0 ){
-    sqlite3RowSetInsert(pIn1->u.pRowSet, pIn3->u.i);
-  }
-  break;
-}
-
-
-#ifndef SQLITE_OMIT_TRIGGER
-
-/* Opcode: Program P1 P2 P3 P4 *
-**
-** Execute the trigger program passed as P4 (type P4_SUBPROGRAM). 
-**
-** P1 contains the address of the memory cell that contains the first memory 
-** cell in an array of values used as arguments to the sub-program. P2 
-** contains the address to jump to if the sub-program throws an IGNORE 
-** exception using the RAISE() function. Register P3 contains the address 
-** of a memory cell in this (the parent) VM that is used to allocate the 
-** memory required by the sub-vdbe at runtime.
-**
-** P4 is a pointer to the VM containing the trigger program.
-*/
-case OP_Program: {        /* jump */
-  int nMem;               /* Number of memory registers for sub-program */
-  int nByte;              /* Bytes of runtime space required for sub-program */
-  Mem *pRt;               /* Register to allocate runtime space */
-  Mem *pMem;              /* Used to iterate through memory cells */
-  Mem *pEnd;              /* Last memory cell in new array */
-  VdbeFrame *pFrame;      /* New vdbe frame to execute in */
-  SubProgram *pProgram;   /* Sub-program to execute */
-  void *t;                /* Token identifying trigger */
-
-  pProgram = pOp->p4.pProgram;
-  pRt = &p->aMem[pOp->p3];
-  assert( pProgram->nOp>0 );
-  
-  /* If the SQLITE_RecTriggers flag is clear, then recursive invocation of
-  ** triggers is disabled for backwards compatibility (flag set/cleared by
-  ** the "PRAGMA recursive_triggers" command). 
-  ** 
-  ** It is recursive invocation of triggers, at the SQL level, that is 
-  ** disabled. In some cases a single trigger may generate more than one 
-  ** SubProgram (if the trigger may be executed with more than one different 
-  ** ON CONFLICT algorithm). SubProgram structures associated with a
-  ** single trigger all have the same value for the SubProgram.token 
-  ** variable.
-  */
-  if( 0==(db->flags&SQLITE_RecTriggers) ){
-    t = pProgram->token;
-    for(pFrame=p->pFrame; pFrame && pFrame->token!=t; pFrame=pFrame->pParent);
-    if( pFrame ) break;
-  }
-
-  if( p->nFrame>db->aLimit[SQLITE_LIMIT_TRIGGER_DEPTH] ){
-    rc = SQLITE_ERROR;
-    sqlite3SetString(&p->zErrMsg, db, "too many levels of trigger recursion");
-    break;
-  }
-
-  /* Register pRt is used to store the memory required to save the state
-  ** of the current program, and the memory required at runtime to execute
-  ** the trigger program. If this trigger has been fired before, then pRt 
-  ** is already allocated. Otherwise, it must be initialized.  */
-  if( (pRt->flags&MEM_Frame)==0 ){
-    /* SubProgram.nMem is set to the number of memory cells used by the 
-    ** program stored in SubProgram.aOp. As well as these, one memory
-    ** cell is required for each cursor used by the program. Set local
-    ** variable nMem (and later, VdbeFrame.nChildMem) to this value.
-    */
-    nMem = pProgram->nMem + pProgram->nCsr;
-    nByte = ROUND8(sizeof(VdbeFrame))
-              + nMem * sizeof(Mem)
-              + pProgram->nCsr * sizeof(VdbeCursor *);
-    pFrame = sqlite3DbMallocZero(db, nByte);
-    if( !pFrame ){
-      goto no_mem;
-    }
-    sqlite3VdbeMemRelease(pRt);
-    pRt->flags = MEM_Frame;
-    pRt->u.pFrame = pFrame;
-
-    pFrame->v = p;
-    pFrame->nChildMem = nMem;
-    pFrame->nChildCsr = pProgram->nCsr;
-    pFrame->pc = pc;
-    pFrame->aMem = p->aMem;
-    pFrame->nMem = p->nMem;
-    pFrame->apCsr = p->apCsr;
-    pFrame->nCursor = p->nCursor;
-    pFrame->aOp = p->aOp;
-    pFrame->nOp = p->nOp;
-    pFrame->token = pProgram->token;
-
-    pEnd = &VdbeFrameMem(pFrame)[pFrame->nChildMem];
-    for(pMem=VdbeFrameMem(pFrame); pMem!=pEnd; pMem++){
-      pMem->flags = MEM_Null;
-      pMem->db = db;
-    }
-  }else{
-    pFrame = pRt->u.pFrame;
-    assert( pProgram->nMem+pProgram->nCsr==pFrame->nChildMem );
-    assert( pProgram->nCsr==pFrame->nChildCsr );
-    assert( pc==pFrame->pc );
-  }
-
-  p->nFrame++;
-  pFrame->pParent = p->pFrame;
-  pFrame->lastRowid = db->lastRowid;
-  pFrame->nChange = p->nChange;
-  p->nChange = 0;
-  p->pFrame = pFrame;
-  p->aMem = &VdbeFrameMem(pFrame)[-1];
-  p->nMem = pFrame->nChildMem;
-  p->nCursor = (u16)pFrame->nChildCsr;
-  p->apCsr = (VdbeCursor **)&p->aMem[p->nMem+1];
-  p->aOp = pProgram->aOp;
-  p->nOp = pProgram->nOp;
-  pc = -1;
-
-  break;
-}
-
-/* Opcode: Param P1 P2 * * *
-**
-** This opcode is only ever present in sub-programs called via the 
-** OP_Program instruction. Copy a value currently stored in a memory 
-** cell of the calling (parent) frame to cell P2 in the current frames 
-** address space. This is used by trigger programs to access the new.* 
-** and old.* values.
-**
-** The address of the cell in the parent frame is determined by adding
-** the value of the P1 argument to the value of the P1 argument to the
-** calling OP_Program instruction.
-*/
-case OP_Param: {           /* out2-prerelease */
-  VdbeFrame *pFrame;
-  Mem *pIn;
-  pFrame = p->pFrame;
-  pIn = &pFrame->aMem[pOp->p1 + pFrame->aOp[pFrame->pc].p1];   
-  sqlite3VdbeMemShallowCopy(pOut, pIn, MEM_Ephem);
-  break;
-}
-
-#endif /* #ifndef SQLITE_OMIT_TRIGGER */
-
-#ifndef SQLITE_OMIT_AUTOINCREMENT
-/* Opcode: MemMax P1 P2 * * *
-**
-** P1 is a register in the root frame of this VM (the root frame is
-** different from the current frame if this instruction is being executed
-** within a sub-program). Set the value of register P1 to the maximum of 
-** its current value and the value in register P2.
-**
-** This instruction throws an error if the memory cell is not initially
-** an integer.
-*/
-case OP_MemMax: {        /* in2 */
-  Mem *pIn1;
-  VdbeFrame *pFrame;
-  if( p->pFrame ){
-    for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
-    pIn1 = &pFrame->aMem[pOp->p1];
-  }else{
-    pIn1 = &p->aMem[pOp->p1];
-  }
-  sqlite3VdbeMemIntegerify(pIn1);
-  sqlite3VdbeMemIntegerify(pIn2);
-  if( pIn1->u.i<pIn2->u.i){
-    pIn1->u.i = pIn2->u.i;
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_AUTOINCREMENT */
-
-/* Opcode: IfPos P1 P2 * * *
-**
-** If the value of register P1 is 1 or greater, jump to P2.
-**
-** It is illegal to use this instruction on a register that does
-** not contain an integer.  An assertion fault will result if you try.
-*/
-case OP_IfPos: {        /* jump, in1 */
-  assert( pIn1->flags&MEM_Int );
-  if( pIn1->u.i>0 ){
-     pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: IfNeg P1 P2 * * *
-**
-** If the value of register P1 is less than zero, jump to P2. 
-**
-** It is illegal to use this instruction on a register that does
-** not contain an integer.  An assertion fault will result if you try.
-*/
-case OP_IfNeg: {        /* jump, in1 */
-  assert( pIn1->flags&MEM_Int );
-  if( pIn1->u.i<0 ){
-     pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: IfZero P1 P2 * * *
-**
-** If the value of register P1 is exactly 0, jump to P2. 
-**
-** It is illegal to use this instruction on a register that does
-** not contain an integer.  An assertion fault will result if you try.
-*/
-case OP_IfZero: {        /* jump, in1 */
-  assert( pIn1->flags&MEM_Int );
-  if( pIn1->u.i==0 ){
-     pc = pOp->p2 - 1;
-  }
-  break;
-}
-
-/* Opcode: AggStep * P2 P3 P4 P5
-**
-** Execute the step function for an aggregate.  The
-** function has P5 arguments.   P4 is a pointer to the FuncDef
-** structure that specifies the function.  Use register
-** P3 as the accumulator.
-**
-** The P5 arguments are taken from register P2 and its
-** successors.
-*/
-case OP_AggStep: {
-  int n;
-  int i;
-  Mem *pMem;
-  Mem *pRec;
-  sqlite3_context ctx;
-  sqlite3_value **apVal;
-
-  n = pOp->p5;
-  assert( n>=0 );
-  pRec = &p->aMem[pOp->p2];
-  apVal = p->apArg;
-  assert( apVal || n==0 );
-  for(i=0; i<n; i++, pRec++){
-    apVal[i] = pRec;
-    storeTypeInfo(pRec, encoding);
-  }
-  ctx.pFunc = pOp->p4.pFunc;
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  ctx.pMem = pMem = &p->aMem[pOp->p3];
-  pMem->n++;
-  ctx.s.flags = MEM_Null;
-  ctx.s.z = 0;
-  ctx.s.zMalloc = 0;
-  ctx.s.xDel = 0;
-  ctx.s.db = db;
-  ctx.isError = 0;
-  ctx.pColl = 0;
-  if( ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
-    assert( pOp>p->aOp );
-    assert( pOp[-1].p4type==P4_COLLSEQ );
-    assert( pOp[-1].opcode==OP_CollSeq );
-    ctx.pColl = pOp[-1].p4.pColl;
-  }
-  (ctx.pFunc->xStep)(&ctx, n, apVal);
-  if( ctx.isError ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&ctx.s));
-    rc = ctx.isError;
-  }
-  sqlite3VdbeMemRelease(&ctx.s);
-  break;
-}
-
-/* Opcode: AggFinal P1 P2 * P4 *
-**
-** Execute the finalizer function for an aggregate.  P1 is
-** the memory location that is the accumulator for the aggregate.
-**
-** P2 is the number of arguments that the step function takes and
-** P4 is a pointer to the FuncDef for this function.  The P2
-** argument is not used by this opcode.  It is only there to disambiguate
-** functions that can take varying numbers of arguments.  The
-** P4 argument is only needed for the degenerate case where
-** the step function was not previously called.
-*/
-case OP_AggFinal: {
-  Mem *pMem;
-  assert( pOp->p1>0 && pOp->p1<=p->nMem );
-  pMem = &p->aMem[pOp->p1];
-  assert( (pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
-  rc = sqlite3VdbeMemFinalize(pMem, pOp->p4.pFunc);
-  if( rc ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(pMem));
-  }
-  sqlite3VdbeChangeEncoding(pMem, encoding);
-  UPDATE_MAX_BLOBSIZE(pMem);
-  if( sqlite3VdbeMemTooBig(pMem) ){
-    goto too_big;
-  }
-  break;
-}
-
-
-#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
-/* Opcode: Vacuum * * * * *
-**
-** Vacuum the entire database.  This opcode will cause other virtual
-** machines to be created and run.  It may not be called from within
-** a transaction.
-*/
-case OP_Vacuum: {
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse; 
-  rc = sqlite3RunVacuum(&p->zErrMsg, db);
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-  break;
-}
-#endif
-
-#if !defined(SQLITE_OMIT_AUTOVACUUM)
-/* Opcode: IncrVacuum P1 P2 * * *
-**
-** Perform a single step of the incremental vacuum procedure on
-** the P1 database. If the vacuum has finished, jump to instruction
-** P2. Otherwise, fall through to the next instruction.
-*/
-case OP_IncrVacuum: {        /* jump */
-  Btree *pBt;
-
-  assert( pOp->p1>=0 && pOp->p1<db->nDb );
-  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
-  pBt = db->aDb[pOp->p1].pBt;
-  rc = sqlite3BtreeIncrVacuum(pBt);
-  if( rc==SQLITE_DONE ){
-    pc = pOp->p2 - 1;
-    rc = SQLITE_OK;
-  }
-  break;
-}
-#endif
-
-/* Opcode: Expire P1 * * * *
-**
-** Cause precompiled statements to become expired. An expired statement
-** fails with an error code of SQLITE_SCHEMA if it is ever executed 
-** (via sqlite3_step()).
-** 
-** If P1 is 0, then all SQL statements become expired. If P1 is non-zero,
-** then only the currently executing statement is affected. 
-*/
-case OP_Expire: {
-  if( !pOp->p1 ){
-    sqlite3ExpirePreparedStatements(db);
-  }else{
-    p->expired = 1;
-  }
-  break;
-}
-
-#ifndef SQLITE_OMIT_SHARED_CACHE
-/* Opcode: TableLock P1 P2 P3 P4 *
-**
-** Obtain a lock on a particular table. This instruction is only used when
-** the shared-cache feature is enabled. 
-**
-** P1 is the index of the database in sqlite3.aDb[] of the database
-** on which the lock is acquired.  A readlock is obtained if P3==0 or
-** a write lock if P3==1.
-**
-** P2 contains the root-page of the table to lock.
-**
-** P4 contains a pointer to the name of the table being locked. This is only
-** used to generate an error message if the lock cannot be obtained.
-*/
-case OP_TableLock: {
-  u8 isWriteLock = (u8)pOp->p3;
-  if( isWriteLock || 0==(db->flags&SQLITE_ReadUncommitted) ){
-    int p1 = pOp->p1; 
-    assert( p1>=0 && p1<db->nDb );
-    assert( (p->btreeMask & (1<<p1))!=0 );
-    assert( isWriteLock==0 || isWriteLock==1 );
-    rc = sqlite3BtreeLockTable(db->aDb[p1].pBt, pOp->p2, isWriteLock);
-    if( (rc&0xFF)==SQLITE_LOCKED ){
-      const char *z = pOp->p4.z;
-      sqlite3SetString(&p->zErrMsg, db, "database table is locked: %s", z);
-    }
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_SHARED_CACHE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VBegin * * * P4 *
-**
-** P4 may be a pointer to an sqlite3_vtab structure. If so, call the 
-** xBegin method for that table.
-**
-** Also, whether or not P4 is set, check that this is not being called from
-** within a callback to a virtual table xSync() method. If it is, the error
-** code will be set to SQLITE_LOCKED.
-*/
-case OP_VBegin: {
-  VTable *pVTab;
-  pVTab = pOp->p4.pVtab;
-  rc = sqlite3VtabBegin(db, pVTab);
-  if( pVTab ){
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = pVTab->pVtab->zErrMsg;
-    pVTab->pVtab->zErrMsg = 0;
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VCreate P1 * * P4 *
-**
-** P4 is the name of a virtual table in database P1. Call the xCreate method
-** for that table.
-*/
-case OP_VCreate: {
-  rc = sqlite3VtabCallCreate(db, pOp->p1, pOp->p4.z, &p->zErrMsg);
-  break;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VDestroy P1 * * P4 *
-**
-** P4 is the name of a virtual table in database P1.  Call the xDestroy method
-** of that table.
-*/
-case OP_VDestroy: {
-  p->inVtabMethod = 2;
-  rc = sqlite3VtabCallDestroy(db, pOp->p1, pOp->p4.z);
-  p->inVtabMethod = 0;
-  break;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VOpen P1 * * P4 *
-**
-** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
-** P1 is a cursor number.  This opcode opens a cursor to the virtual
-** table and stores that cursor in P1.
-*/
-case OP_VOpen: {
-  VdbeCursor *pCur;
-  sqlite3_vtab_cursor *pVtabCursor;
-  sqlite3_vtab *pVtab;
-  sqlite3_module *pModule;
-
-  pCur = 0;
-  pVtabCursor = 0;
-  pVtab = pOp->p4.pVtab->pVtab;
-  pModule = (sqlite3_module *)pVtab->pModule;
-  assert(pVtab && pModule);
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  rc = pModule->xOpen(pVtab, &pVtabCursor);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = pVtab->zErrMsg;
-  pVtab->zErrMsg = 0;
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-  if( SQLITE_OK==rc ){
-    /* Initialize sqlite3_vtab_cursor base class */
-    pVtabCursor->pVtab = pVtab;
-
-    /* Initialise vdbe cursor object */
-    pCur = allocateCursor(p, pOp->p1, 0, -1, 0);
-    if( pCur ){
-      pCur->pVtabCursor = pVtabCursor;
-      pCur->pModule = pVtabCursor->pVtab->pModule;
-    }else{
-      db->mallocFailed = 1;
-      pModule->xClose(pVtabCursor);
-    }
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VFilter P1 P2 P3 P4 *
-**
-** P1 is a cursor opened using VOpen.  P2 is an address to jump to if
-** the filtered result set is empty.
-**
-** P4 is either NULL or a string that was generated by the xBestIndex
-** method of the module.  The interpretation of the P4 string is left
-** to the module implementation.
-**
-** This opcode invokes the xFilter method on the virtual table specified
-** by P1.  The integer query plan parameter to xFilter is stored in register
-** P3. Register P3+1 stores the argc parameter to be passed to the
-** xFilter method. Registers P3+2..P3+1+argc are the argc
-** additional parameters which are passed to
-** xFilter as argv. Register P3+2 becomes argv[0] when passed to xFilter.
-**
-** A jump is made to P2 if the result set after filtering would be empty.
-*/
-case OP_VFilter: {   /* jump */
-  int nArg;
-  int iQuery;
-  const sqlite3_module *pModule;
-  Mem *pQuery;
-  Mem *pArgc;
-  sqlite3_vtab_cursor *pVtabCursor;
-  sqlite3_vtab *pVtab;
-  VdbeCursor *pCur;
-  int res;
-  int i;
-  Mem **apArg;
-
-  pQuery = &p->aMem[pOp->p3];
-  pArgc = &pQuery[1];
-  pCur = p->apCsr[pOp->p1];
-  REGISTER_TRACE(pOp->p3, pQuery);
-  assert( pCur->pVtabCursor );
-  pVtabCursor = pCur->pVtabCursor;
-  pVtab = pVtabCursor->pVtab;
-  pModule = pVtab->pModule;
-
-  /* Grab the index number and argc parameters */
-  assert( (pQuery->flags&MEM_Int)!=0 && pArgc->flags==MEM_Int );
-  nArg = (int)pArgc->u.i;
-  iQuery = (int)pQuery->u.i;
-
-  /* Invoke the xFilter method */
-  {
-    res = 0;
-    apArg = p->apArg;
-    for(i = 0; i<nArg; i++){
-      apArg[i] = &pArgc[i+1];
-      storeTypeInfo(apArg[i], 0);
-    }
-
-    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-    p->inVtabMethod = 1;
-    rc = pModule->xFilter(pVtabCursor, iQuery, pOp->p4.z, nArg, apArg);
-    p->inVtabMethod = 0;
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = pVtab->zErrMsg;
-    pVtab->zErrMsg = 0;
-    if( rc==SQLITE_OK ){
-      res = pModule->xEof(pVtabCursor);
-    }
-    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-
-    if( res ){
-      pc = pOp->p2 - 1;
-    }
-  }
-  pCur->nullRow = 0;
-
-  break;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VColumn P1 P2 P3 * *
-**
-** Store the value of the P2-th column of
-** the row of the virtual-table that the 
-** P1 cursor is pointing to into register P3.
-*/
-case OP_VColumn: {
-  sqlite3_vtab *pVtab;
-  const sqlite3_module *pModule;
-  Mem *pDest;
-  sqlite3_context sContext;
-
-  VdbeCursor *pCur = p->apCsr[pOp->p1];
-  assert( pCur->pVtabCursor );
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pDest = &p->aMem[pOp->p3];
-  if( pCur->nullRow ){
-    sqlite3VdbeMemSetNull(pDest);
-    break;
-  }
-  pVtab = pCur->pVtabCursor->pVtab;
-  pModule = pVtab->pModule;
-  assert( pModule->xColumn );
-  memset(&sContext, 0, sizeof(sContext));
-
-  /* The output cell may already have a buffer allocated. Move
-  ** the current contents to sContext.s so in case the user-function 
-  ** can use the already allocated buffer instead of allocating a 
-  ** new one.
-  */
-  sqlite3VdbeMemMove(&sContext.s, pDest);
-  MemSetTypeFlag(&sContext.s, MEM_Null);
-
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  rc = pModule->xColumn(pCur->pVtabCursor, &sContext, pOp->p2);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = pVtab->zErrMsg;
-  pVtab->zErrMsg = 0;
-  if( sContext.isError ){
-    rc = sContext.isError;
-  }
-
-  /* Copy the result of the function to the P3 register. We
-  ** do this regardless of whether or not an error occurred to ensure any
-  ** dynamic allocation in sContext.s (a Mem struct) is  released.
-  */
-  sqlite3VdbeChangeEncoding(&sContext.s, encoding);
-  REGISTER_TRACE(pOp->p3, pDest);
-  sqlite3VdbeMemMove(pDest, &sContext.s);
-  UPDATE_MAX_BLOBSIZE(pDest);
-
-  if( sqlite3SafetyOn(db) ){
-    goto abort_due_to_misuse;
-  }
-  if( sqlite3VdbeMemTooBig(pDest) ){
-    goto too_big;
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VNext P1 P2 * * *
-**
-** Advance virtual table P1 to the next row in its result set and
-** jump to instruction P2.  Or, if the virtual table has reached
-** the end of its result set, then fall through to the next instruction.
-*/
-case OP_VNext: {   /* jump */
-  sqlite3_vtab *pVtab;
-  const sqlite3_module *pModule;
-  int res;
-  VdbeCursor *pCur;
-
-  res = 0;
-  pCur = p->apCsr[pOp->p1];
-  assert( pCur->pVtabCursor );
-  if( pCur->nullRow ){
-    break;
-  }
-  pVtab = pCur->pVtabCursor->pVtab;
-  pModule = pVtab->pModule;
-  assert( pModule->xNext );
-
-  /* Invoke the xNext() method of the module. There is no way for the
-  ** underlying implementation to return an error if one occurs during
-  ** xNext(). Instead, if an error occurs, true is returned (indicating that 
-  ** data is available) and the error code returned when xColumn or
-  ** some other method is next invoked on the save virtual table cursor.
-  */
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  p->inVtabMethod = 1;
-  rc = pModule->xNext(pCur->pVtabCursor);
-  p->inVtabMethod = 0;
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = pVtab->zErrMsg;
-  pVtab->zErrMsg = 0;
-  if( rc==SQLITE_OK ){
-    res = pModule->xEof(pCur->pVtabCursor);
-  }
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-
-  if( !res ){
-    /* If there is data, jump to P2 */
-    pc = pOp->p2 - 1;
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VRename P1 * * P4 *
-**
-** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
-** This opcode invokes the corresponding xRename method. The value
-** in register P1 is passed as the zName argument to the xRename method.
-*/
-case OP_VRename: {
-  sqlite3_vtab *pVtab;
-  Mem *pName;
-
-  pVtab = pOp->p4.pVtab->pVtab;
-  pName = &p->aMem[pOp->p1];
-  assert( pVtab->pModule->xRename );
-  REGISTER_TRACE(pOp->p1, pName);
-  assert( pName->flags & MEM_Str );
-  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-  rc = pVtab->pModule->xRename(pVtab, pName->z);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = pVtab->zErrMsg;
-  pVtab->zErrMsg = 0;
-  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-
-  break;
-}
-#endif
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-/* Opcode: VUpdate P1 P2 P3 P4 *
-**
-** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
-** This opcode invokes the corresponding xUpdate method. P2 values
-** are contiguous memory cells starting at P3 to pass to the xUpdate 
-** invocation. The value in register (P3+P2-1) corresponds to the 
-** p2th element of the argv array passed to xUpdate.
-**
-** The xUpdate method will do a DELETE or an INSERT or both.
-** The argv[0] element (which corresponds to memory cell P3)
-** is the rowid of a row to delete.  If argv[0] is NULL then no 
-** deletion occurs.  The argv[1] element is the rowid of the new 
-** row.  This can be NULL to have the virtual table select the new 
-** rowid for itself.  The subsequent elements in the array are 
-** the values of columns in the new row.
-**
-** If P2==1 then no insert is performed.  argv[0] is the rowid of
-** a row to delete.
-**
-** P1 is a boolean flag. If it is set to true and the xUpdate call
-** is successful, then the value returned by sqlite3_last_insert_rowid() 
-** is set to the value of the rowid for the row just inserted.
-*/
-case OP_VUpdate: {
-  sqlite3_vtab *pVtab;
-  sqlite3_module *pModule;
-  int nArg;
-  int i;
-  sqlite_int64 rowid;
-  Mem **apArg;
-  Mem *pX;
-
-  pVtab = pOp->p4.pVtab->pVtab;
-  pModule = (sqlite3_module *)pVtab->pModule;
-  nArg = pOp->p2;
-  assert( pOp->p4type==P4_VTAB );
-  if( ALWAYS(pModule->xUpdate) ){
-    apArg = p->apArg;
-    pX = &p->aMem[pOp->p3];
-    for(i=0; i<nArg; i++){
-      storeTypeInfo(pX, 0);
-      apArg[i] = pX;
-      pX++;
-    }
-    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
-    rc = pModule->xUpdate(pVtab, nArg, apArg, &rowid);
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = pVtab->zErrMsg;
-    pVtab->zErrMsg = 0;
-    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
-    if( rc==SQLITE_OK && pOp->p1 ){
-      assert( nArg>1 && apArg[0] && (apArg[0]->flags&MEM_Null) );
-      db->lastRowid = rowid;
-    }
-    p->nChange++;
-  }
-  break;
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
-#ifndef  SQLITE_OMIT_PAGER_PRAGMAS
-/* Opcode: Pagecount P1 P2 * * *
-**
-** Write the current number of pages in database P1 to memory cell P2.
-*/
-case OP_Pagecount: {            /* out2-prerelease */
-  int p1;
-  int nPage;
-  Pager *pPager;
-
-  p1 = pOp->p1; 
-  pPager = sqlite3BtreePager(db->aDb[p1].pBt);
-  rc = sqlite3PagerPagecount(pPager, &nPage);
-  /* OP_Pagecount is always called from within a read transaction.  The
-  ** page count has already been successfully read and cached.  So the
-  ** sqlite3PagerPagecount() call above cannot fail. */
-  if( ALWAYS(rc==SQLITE_OK) ){
-    pOut->flags = MEM_Int;
-    pOut->u.i = nPage;
-  }
-  break;
-}
-#endif
-
-#ifndef SQLITE_OMIT_TRACE
-/* Opcode: Trace * * * P4 *
-**
-** If tracing is enabled (by the sqlite3_trace()) interface, then
-** the UTF-8 string contained in P4 is emitted on the trace callback.
-*/
-case OP_Trace: {
-  char *zTrace;
-
-  zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql);
-  if( zTrace ){
-    if( db->xTrace ){
-      db->xTrace(db->pTraceArg, zTrace);
-    }
-#ifdef SQLITE_DEBUG
-    if( (db->flags & SQLITE_SqlTrace)!=0 ){
-      sqlite3DebugPrintf("SQL-trace: %s\n", zTrace);
-    }
-#endif /* SQLITE_DEBUG */
-  }
-  break;
-}
-#endif
-
-
-/* Opcode: Noop * * * * *
-**
-** Do nothing.  This instruction is often useful as a jump
-** destination.
-*/
-/*
-** The magic Explain opcode are only inserted when explain==2 (which
-** is to say when the EXPLAIN QUERY PLAN syntax is used.)
-** This opcode records information from the optimizer.  It is the
-** the same as a no-op.  This opcodesnever appears in a real VM program.
-*/
-default: {          /* This is really OP_Noop and OP_Explain */
-  break;
-}
-
-/*****************************************************************************
-** The cases of the switch statement above this line should all be indented
-** by 6 spaces.  But the left-most 6 spaces have been removed to improve the
-** readability.  From this point on down, the normal indentation rules are
-** restored.
-*****************************************************************************/
-    }
-
-#ifdef VDBE_PROFILE
-    {
-      u64 elapsed = sqlite3Hwtime() - start;
-      pOp->cycles += elapsed;
-      pOp->cnt++;
-#if 0
-        fprintf(stdout, "%10llu ", elapsed);
-        sqlite3VdbePrintOp(stdout, origPc, &p->aOp[origPc]);
-#endif
-    }
-#endif
-
-    /* The following code adds nothing to the actual functionality
-    ** of the program.  It is only here for testing and debugging.
-    ** On the other hand, it does burn CPU cycles every time through
-    ** the evaluator loop.  So we can leave it out when NDEBUG is defined.
-    */
-#ifndef NDEBUG
-    assert( pc>=-1 && pc<p->nOp );
-
-#ifdef SQLITE_DEBUG
-    if( p->trace ){
-      if( rc!=0 ) fprintf(p->trace,"rc=%d\n",rc);
-      if( opProperty & OPFLG_OUT2_PRERELEASE ){
-        registerTrace(p->trace, pOp->p2, pOut);
-      }
-      if( opProperty & OPFLG_OUT3 ){
-        registerTrace(p->trace, pOp->p3, pOut);
-      }
-    }
-#endif  /* SQLITE_DEBUG */
-#endif  /* NDEBUG */
-  }  /* The end of the for(;;) loop the loops through opcodes */
-
-  /* If we reach this point, it means that execution is finished with
-  ** an error of some kind.
-  */
-vdbe_error_halt:
-  assert( rc );
-  p->rc = rc;
-  sqlite3VdbeHalt(p);
-  if( rc==SQLITE_IOERR_NOMEM ) db->mallocFailed = 1;
-  rc = SQLITE_ERROR;
-
-  /* This is the only way out of this procedure.  We have to
-  ** release the mutexes on btrees that were acquired at the
-  ** top. */
-vdbe_return:
-  sqlite3BtreeMutexArrayLeave(&p->aMutex);
-  return rc;
-
-  /* Jump to here if a string or blob larger than SQLITE_MAX_LENGTH
-  ** is encountered.
-  */
-too_big:
-  sqlite3SetString(&p->zErrMsg, db, "string or blob too big");
-  rc = SQLITE_TOOBIG;
-  goto vdbe_error_halt;
-
-  /* Jump to here if a malloc() fails.
-  */
-no_mem:
-  db->mallocFailed = 1;
-  sqlite3SetString(&p->zErrMsg, db, "out of memory");
-  rc = SQLITE_NOMEM;
-  goto vdbe_error_halt;
-
-  /* Jump to here for an SQLITE_MISUSE error.
-  */
-abort_due_to_misuse:
-  rc = SQLITE_MISUSE;
-  /* Fall thru into abort_due_to_error */
-
-  /* Jump to here for any other kind of fatal error.  The "rc" variable
-  ** should hold the error number.
-  */
-abort_due_to_error:
-  assert( p->zErrMsg==0 );
-  if( db->mallocFailed ) rc = SQLITE_NOMEM;
-  if( rc!=SQLITE_IOERR_NOMEM ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(rc));
-  }
-  goto vdbe_error_halt;
-
-  /* Jump to here if the sqlite3_interrupt() API sets the interrupt
-  ** flag.
-  */
-abort_due_to_interrupt:
-  assert( db->u1.isInterrupted );
-  rc = SQLITE_INTERRUPT;
-  p->rc = rc;
-  sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(rc));
-  goto vdbe_error_halt;
-}