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Overview
Comment:Simplify the OPFLG processing logic in the VDBE for a speed boost in the VDBE processing loop and a reduction in code size.
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Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 3352b3eba545c3128efb7665ec91d4df3b16011d
User & Date: drh 2009-11-13 19:43:44.000
Context
2009-11-13
20:52
Performance improvements and size reductions on the OP_Seek* family of VDBE opcodes. (check-in: ed820f45cf user: drh tags: trunk)
19:43
Simplify the OPFLG processing logic in the VDBE for a speed boost in the VDBE processing loop and a reduction in code size. (check-in: 3352b3eba5 user: drh tags: trunk)
17:05
Force 8-byte memory alignment on memory allocated for VDBE cursors. (check-in: bdc45ba77f user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to mkopcodeh.awk.
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  sub("\r","",name)
  op[name] = -1
  jump[name] = 0
  out2_prerelease[name] = 0
  in1[name] = 0
  in2[name] = 0
  in3[name] = 0

  out3[name] = 0
  for(i=3; i<NF; i++){
    if($i=="same" && $(i+1)=="as"){
      sym = $(i+2)
      sub(/,/,"",sym)
      op[name] = tk[sym]
      used[op[name]] = 1







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  sub("\r","",name)
  op[name] = -1
  jump[name] = 0
  out2_prerelease[name] = 0
  in1[name] = 0
  in2[name] = 0
  in3[name] = 0
  out2[name] = 0
  out3[name] = 0
  for(i=3; i<NF; i++){
    if($i=="same" && $(i+1)=="as"){
      sym = $(i+2)
      sub(/,/,"",sym)
      op[name] = tk[sym]
      used[op[name]] = 1
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      out2_prerelease[name] = 1
    }else if(x=="in1"){
      in1[name] = 1
    }else if(x=="in2"){
      in2[name] = 1
    }else if(x=="in3"){
      in3[name] = 1


    }else if(x=="out3"){
      out3[name] = 1
    }
  }
  order[n_op++] = name;
}








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      out2_prerelease[name] = 1
    }else if(x=="in1"){
      in1[name] = 1
    }else if(x=="in2"){
      in2[name] = 1
    }else if(x=="in3"){
      in3[name] = 1
    }else if(x=="out2"){
      out2[name] = 1
    }else if(x=="out3"){
      out3[name] = 1
    }
  }
  order[n_op++] = name;
}

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  #  bit 2:     output to p1.  release p1 before opcode runs
  #
  for(i=0; i<=max; i++) bv[i] = 0;
  for(i=0; i<n_op; i++){
    name = order[i];
    x = op[name]
    a0 = a1 = a2 = a3 = a4 = a5 = a6 = a7 = 0
    # a8 = a9 = a10 = a11 = a12 = a13 = a14 = a15 = 0
    if( jump[name] ) a0 = 1;
    if( out2_prerelease[name] ) a1 = 2;
    if( in1[name] ) a2 = 4;
    if( in2[name] ) a3 = 8;
    if( in3[name] ) a4 = 16;

    if( out3[name] ) a5 = 32;
    # bv[x] = a0+a1+a2+a3+a4+a5+a6+a7+a8+a9+a10+a11+a12+a13+a14+a15;
    bv[x] = a0+a1+a2+a3+a4+a5+a6+a7;
  }
  print "\n"
  print "/* Properties such as \"out2\" or \"jump\" that are specified in"
  print "** comments following the \"case\" for each opcode in the vdbe.c"
  print "** are encoded into bitvectors as follows:"
  print "*/"
  print "#define OPFLG_JUMP            0x0001  /* jump:  P2 holds jmp target */"
  print "#define OPFLG_OUT2_PRERELEASE 0x0002  /* out2-prerelease: */"
  print "#define OPFLG_IN1             0x0004  /* in1:   P1 is an input */"
  print "#define OPFLG_IN2             0x0008  /* in2:   P2 is an input */"
  print "#define OPFLG_IN3             0x0010  /* in3:   P3 is an input */"

  print "#define OPFLG_OUT3            0x0020  /* out3:  P3 is an output */"
  print "#define OPFLG_INITIALIZER {\\"
  for(i=0; i<=max; i++){
    if( i%8==0 ) printf("/* %3d */",i)
    printf " 0x%02x,", bv[i]
    if( i%8==7 ) printf("\\\n");
  }
  print "}"
}







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  #  bit 2:     output to p1.  release p1 before opcode runs
  #
  for(i=0; i<=max; i++) bv[i] = 0;
  for(i=0; i<n_op; i++){
    name = order[i];
    x = op[name]
    a0 = a1 = a2 = a3 = a4 = a5 = a6 = a7 = 0
    # a7 = a9 = a10 = a11 = a12 = a13 = a14 = a15 = 0
    if( jump[name] ) a0 = 1;
    if( out2_prerelease[name] ) a1 = 2;
    if( in1[name] ) a2 = 4;
    if( in2[name] ) a3 = 8;
    if( in3[name] ) a4 = 16;
    if( out2[name] ) a5 = 32;
    if( out3[name] ) a6 = 64;
    # bv[x] = a0+a1+a2+a3+a4+a5+a6+a7+a8+a9+a10+a11+a12+a13+a14+a15;
    bv[x] = a0+a1+a2+a3+a4+a5+a6+a7;
  }
  print "\n"
  print "/* Properties such as \"out2\" or \"jump\" that are specified in"
  print "** comments following the \"case\" for each opcode in the vdbe.c"
  print "** are encoded into bitvectors as follows:"
  print "*/"
  print "#define OPFLG_JUMP            0x0001  /* jump:  P2 holds jmp target */"
  print "#define OPFLG_OUT2_PRERELEASE 0x0002  /* out2-prerelease: */"
  print "#define OPFLG_IN1             0x0004  /* in1:   P1 is an input */"
  print "#define OPFLG_IN2             0x0008  /* in2:   P2 is an input */"
  print "#define OPFLG_IN3             0x0010  /* in3:   P3 is an input */"
  print "#define OPFLG_OUT2            0x0020  /* out2:  P2 is an output */"
  print "#define OPFLG_OUT3            0x0040  /* out3:  P3 is an output */"
  print "#define OPFLG_INITIALIZER {\\"
  for(i=0; i<=max; i++){
    if( i%8==0 ) printf("/* %3d */",i)
    printf " 0x%02x,", bv[i]
    if( i%8==7 ) printf("\\\n");
  }
  print "}"
}
Changes to src/vdbe.c.
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    /* 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







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    /* 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 | OPFLG_IN1 | OPFLG_IN2
                      | OPFLG_IN3 | OPFLG_OUT2 | OPFLG_OUT3)
    ){
      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{












        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|OPFLG_OUT2))!=0 ){
          assert( pOp->p2>0 );
          assert( pOp->p2<=p->nMem );




          assert( (opProperty & OPFLG_OUT2)==0 || (opProperty & OPFLG_IN3)==0 );


          pIn2 = pOut = &p->aMem[pOp->p2];
        }
        if( (opProperty & (OPFLG_IN3|OPFLG_OUT3))!=0 ){
          assert( pOp->p3>0 );
          assert( pOp->p3<=p->nMem );
          pIn3 = pOut = &p->aMem[pOp->p3];

        }




#ifdef SQLITE_DEBUG
        if( opProperty & OPFLG_IN2 ){ REGISTER_TRACE(pOp->p2, pIn2); }




        if( opProperty & OPFLG_IN3 ){ REGISTER_TRACE(pOp->p3, pIn3); }
#endif
      }
    }
  
    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
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}

/* 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;
}







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}

/* Opcode:  Gosub P1 P2 * * *
**
** Write the current address onto register P1
** and then jump to address P2.
*/
case OP_Gosub: {            /* jump, in1 */



  assert( (pIn1->flags & MEM_Dyn)==0 );
  pIn1->flags = MEM_Int;
  pIn1->u.i = pc;
  REGISTER_TRACE(pOp->p1, pIn1);
  pc = pOp->p2 - 1;
  break;
}
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/* 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 * * *







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/* 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, out2 */



  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, out2 */




  assert( pOut!=pIn1 );
  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
  REGISTER_TRACE(pOp->p2, pOut);
  break;
}

/* Opcode: ResultRow P1 P2 * * *
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/* 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;
}







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/* 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, out2 */

  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, out2 */

  if( pIn1->flags & MEM_Null ){
    sqlite3VdbeMemSetNull(pOut);
  }else{
    sqlite3VdbeMemSetInt64(pOut, ~sqlite3VdbeIntValue(pIn1));
  }
  break;
}
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**
** 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 );







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**
** 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 */
case OP_IdxGE: {        /* jump */
  VdbeCursor *pC;
  int res;
  UnpackedRecord r;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
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4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
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/* 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
**







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<







4661
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4664
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4669
4670
4671
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4685

4686


4687
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4692
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4694

4695
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/* 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: {       /* in1, in2 */






  assert( (pIn2->flags & MEM_Int)!=0 );
  if( (pIn1->flags & MEM_RowSet)==0 ){
    sqlite3VdbeMemSetRowSet(pIn1);
    if( (pIn1->flags & MEM_RowSet)==0 ) goto no_mem;
  }
  sqlite3RowSetInsert(pIn1->u.pRowSet, pIn2->u.i);
  break;
}

/* Opcode: RowSetRead P1 P2 P3 * *
**
** Extract the smallest value from boolean index P1 and put that value into
** register P3.  Or, if boolean index P1 is initially empty, leave P3
** unchanged and jump to instruction P2.
*/
case OP_RowSetRead: {       /* jump, in1, out3 */

  i64 val;

  CHECK_FOR_INTERRUPT;


  if( (pIn1->flags & MEM_RowSet)==0 
   || sqlite3RowSetNext(pIn1->u.pRowSet, &val)==0
  ){
    /* The boolean index is empty */
    sqlite3VdbeMemSetNull(pIn1);
    pc = pOp->p2 - 1;
  }else{
    /* A value was pulled from the index */

    sqlite3VdbeMemSetInt64(pOut, val);
  }
  break;
}

/* Opcode: RowSetTest P1 P2 P3 P4
**