/ Check-in [80236e81ce]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Remove more column-cache residue: The OP_SetColTab and OP_VerifyColTab opcodes and the associated SQLITE_DEBUG_COLUMNCACHE logic.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | omit-column-cache
Files: files | file ages | folders
SHA3-256: 80236e81cefdf3d3cda3dbdb6de1575c38e4e248cc4b72ca9ee96d3aa0464bfd
User & Date: drh 2018-08-04 16:54:53
Context
2018-08-04
17:15
Fix comments that were made obsolete by the removal of the column cache. check-in: 2041231d56 user: drh tags: omit-column-cache
16:54
Remove more column-cache residue: The OP_SetColTab and OP_VerifyColTab opcodes and the associated SQLITE_DEBUG_COLUMNCACHE logic. check-in: 80236e81ce user: drh tags: omit-column-cache
15:53
Further logic simplifications that flow out of the omission of the column cache. check-in: 7d9072b027 user: drh tags: omit-column-cache
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/sqliteInt.h.

363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
#if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
# define NDEBUG 1
#endif
#if defined(NDEBUG) && defined(SQLITE_DEBUG)
# undef NDEBUG
#endif

/* SQLITE_DEBUG_COLUMNCACHE is synomous with SQLITE_DEBUG.  The 
** SQLITE_DEBUG_COLUMNCACHE symbol only exists to provide a convenient
** way to search for all code that deals with verifying correct behavior
** of the column cache.
*/
#ifdef SQLITE_DEBUG
# define SQLITE_DEBUG_COLUMNCACHE 1
#else
# undef SQLIT_DEBUG_COLUMNCACHE
#endif

/*
** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
*/
#if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
# define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
#endif








<
<
<
<
<
<
<
<
<
<
<







363
364
365
366
367
368
369











370
371
372
373
374
375
376
#if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
# define NDEBUG 1
#endif
#if defined(NDEBUG) && defined(SQLITE_DEBUG)
# undef NDEBUG
#endif












/*
** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
*/
#if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
# define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
#endif

Changes to src/vdbe.c.

32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
....
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
....
7440
7441
7442
7443
7444
7445
7446
7447
7448
7449
7450
7451
7452
7453
7454
7455
7456
7457
7458
7459
7460
7461
7462
7463
7464
7465
7466
7467
7468
7469
7470
7471
7472
7473
7474
7475
7476
7477
7478
7479
7480
7481
*/
#ifdef SQLITE_DEBUG
# define memAboutToChange(P,M) sqlite3VdbeMemAboutToChange(P,M)
#else
# define memAboutToChange(P,M)
#endif

/*
** Given a cursor number and a column for a table or index, compute a
** hash value for use in the Mem.iTabColHash value.  The iTabColHash
** column is only used for verification - it is omitted from production
** builds.  Collisions are harmless in the sense that the correct answer
** still results.  The only harm of collisions is that they can potential
** reduce column-cache error detection during SQLITE_DEBUG builds.
**
** No valid hash should be 0.
*/
#define TableColumnHash(T,C)  (((u32)(T)<<16)^(u32)(C+2))

/*
** 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.
*/
................................................................................
  assert( pOut!=pIn1 );
  while( 1 ){
    memAboutToChange(p, pOut);
    sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
    Deephemeralize(pOut);
#ifdef SQLITE_DEBUG
    pOut->pScopyFrom = 0;
    pOut->iTabColHash = 0;
#endif
    REGISTER_TRACE(pOp->p2+pOp->p3-n, pOut);
    if( (n--)==0 ) break;
    pOut++;
    pIn1++;
  }
  break;
................................................................................
** An Abort is safe if either there have been no writes, or if there is
** an active statement journal.
*/
case OP_Abortable: {
  sqlite3VdbeAssertAbortable(p);
  break;
}
#endif

#ifdef SQLITE_DEBUG_COLUMNCACHE
/* Opcode:  SetTabCol   P1 P2 P3 * *
**
** Set a flag in register REG[P3] indicating that it holds the value
** of column P2 from the table on cursor P1.  This flag is checked
** by a subsequent VerifyTabCol opcode.
**
** This opcode only appears SQLITE_DEBUG builds.  It is used to verify
** that the expression table column cache is working correctly.
*/
case OP_SetTabCol: {
  aMem[pOp->p3].iTabColHash = TableColumnHash(pOp->p1,pOp->p2);
  break;
}
/* Opcode:  VerifyTabCol   P1 P2 P3 * *
**
** Verify that register REG[P3] contains the value of column P2 from
** cursor P1.  Assert() if this is not the case.
**
** This opcode only appears SQLITE_DEBUG builds.  It is used to verify
** that the expression table column cache is working correctly.
*/
case OP_VerifyTabCol: {
  assert( aMem[pOp->p3].iTabColHash == TableColumnHash(pOp->p1,pOp->p2) );
  break;
}
#endif

/* Opcode: Noop * * * * *
**
** Do nothing.  This instruction is often useful as a jump
** destination.
*/







<
<
<
<
<
<
<
<
<
<
<
<







 







<







 







<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<







32
33
34
35
36
37
38












39
40
41
42
43
44
45
....
1292
1293
1294
1295
1296
1297
1298

1299
1300
1301
1302
1303
1304
1305
....
7427
7428
7429
7430
7431
7432
7433




























7434
7435
7436
7437
7438
7439
7440
*/
#ifdef SQLITE_DEBUG
# define memAboutToChange(P,M) sqlite3VdbeMemAboutToChange(P,M)
#else
# define memAboutToChange(P,M)
#endif













/*
** 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.
*/
................................................................................
  assert( pOut!=pIn1 );
  while( 1 ){
    memAboutToChange(p, pOut);
    sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
    Deephemeralize(pOut);
#ifdef SQLITE_DEBUG
    pOut->pScopyFrom = 0;

#endif
    REGISTER_TRACE(pOp->p2+pOp->p3-n, pOut);
    if( (n--)==0 ) break;
    pOut++;
    pIn1++;
  }
  break;
................................................................................
** An Abort is safe if either there have been no writes, or if there is
** an active statement journal.
*/
case OP_Abortable: {
  sqlite3VdbeAssertAbortable(p);
  break;
}




























#endif

/* Opcode: Noop * * * * *
**
** Do nothing.  This instruction is often useful as a jump
** destination.
*/

Changes to src/vdbeInt.h.

207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
  u32 uTemp;          /* Transient storage for serial_type in OP_MakeRecord */
  sqlite3 *db;        /* The associated database connection */
  void (*xDel)(void*);/* Destructor for Mem.z - only valid if MEM_Dyn */
#ifdef SQLITE_DEBUG
  Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
  u16 mScopyFlags;    /* flags value immediately after the shallow copy */
#endif
#ifdef SQLITE_DEBUG_COLUMNCACHE
  u32 iTabColHash;    /* Hash of table.column that is origin of this value */
  u32 iPadding;       /* sqlite3_value objects must be 8-byte aligned */
#endif
};

/*
** Size of struct Mem not including the Mem.zMalloc member or anything that
** follows.
*/
#define MEMCELLSIZE offsetof(Mem,zMalloc)







<
<
<
<







207
208
209
210
211
212
213




214
215
216
217
218
219
220
  u32 uTemp;          /* Transient storage for serial_type in OP_MakeRecord */
  sqlite3 *db;        /* The associated database connection */
  void (*xDel)(void*);/* Destructor for Mem.z - only valid if MEM_Dyn */
#ifdef SQLITE_DEBUG
  Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
  u16 mScopyFlags;    /* flags value immediately after the shallow copy */
#endif




};

/*
** Size of struct Mem not including the Mem.zMalloc member or anything that
** follows.
*/
#define MEMCELLSIZE offsetof(Mem,zMalloc)

Changes to src/vdbeapi.c.

968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
        /* .uTemp      = */ (u32)0,
        /* .db         = */ (sqlite3*)0,
        /* .xDel       = */ (void(*)(void*))0,
#ifdef SQLITE_DEBUG
        /* .pScopyFrom = */ (Mem*)0,
        /* .mScopyFlags= */ 0,
#endif
#ifdef SQLITE_DEBUG_COLUMNCACHE
        /* .iTabColHash= */ 0,
#endif
      };
  return &nullMem;
}

/*
** Check to see if column iCol of the given statement is valid.  If
** it is, return a pointer to the Mem for the value of that column.







<
<
<







968
969
970
971
972
973
974



975
976
977
978
979
980
981
        /* .uTemp      = */ (u32)0,
        /* .db         = */ (sqlite3*)0,
        /* .xDel       = */ (void(*)(void*))0,
#ifdef SQLITE_DEBUG
        /* .pScopyFrom = */ (Mem*)0,
        /* .mScopyFlags= */ 0,
#endif



      };
  return &nullMem;
}

/*
** Check to see if column iCol of the given statement is valid.  If
** it is, return a pointer to the Mem for the value of that column.

Changes to src/vdbeaux.c.

1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
  while( (N--)>0 ){
    p->db = db;
    p->flags = flags;
    p->szMalloc = 0;
#ifdef SQLITE_DEBUG
    p->pScopyFrom = 0;
#endif
#ifdef SQLITE_DEBUG_COLUMNCACHE
    p->iTabColHash = 0;
#endif
    p++;
  }
}

/*
** Release an array of N Mem elements
*/







<
<
<







1635
1636
1637
1638
1639
1640
1641



1642
1643
1644
1645
1646
1647
1648
  while( (N--)>0 ){
    p->db = db;
    p->flags = flags;
    p->szMalloc = 0;
#ifdef SQLITE_DEBUG
    p->pScopyFrom = 0;
#endif



    p++;
  }
}

/*
** Release an array of N Mem elements
*/

Changes to src/vdbemem.c.

930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
...
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
...
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
      /* pMem is the register that is changing.  But also mark pX as
      ** undefined so that we can quickly detect the shallow-copy error */
      pX->flags = MEM_Undefined;
      pX->pScopyFrom = 0;
    }
  }
  pMem->pScopyFrom = 0;
#ifdef SQLITE_DEBUG_COLUMN_CACHE
  pMem->iTabColHash = 0;
#endif
}
#endif /* SQLITE_DEBUG */


/*
** Make an shallow copy of pFrom into pTo.  Prior contents of
** pTo are freed.  The pFrom->z field is not duplicated.  If
................................................................................
  sqlite3VdbeMemShallowCopy(pTo, pFrom, eType);
}
void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){
  assert( (pFrom->flags & MEM_RowSet)==0 );
  assert( pTo->db==pFrom->db );
  if( VdbeMemDynamic(pTo) ){ vdbeClrCopy(pTo,pFrom,srcType); return; }
  memcpy(pTo, pFrom, MEMCELLSIZE);
#ifdef SQLITE_DEBUG_COLUMNCACHE
  pTo->iTabColHash = pFrom->iTabColHash;
#endif
  if( (pFrom->flags&MEM_Static)==0 ){
    pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem);
    assert( srcType==MEM_Ephem || srcType==MEM_Static );
    pTo->flags |= srcType;
  }
}

................................................................................
*/
int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
  int rc = SQLITE_OK;

  assert( (pFrom->flags & MEM_RowSet)==0 );
  if( VdbeMemDynamic(pTo) ) vdbeMemClearExternAndSetNull(pTo);
  memcpy(pTo, pFrom, MEMCELLSIZE);
#ifdef SQLITE_DEBUG_COLUMNCACHE
  pTo->iTabColHash = pFrom->iTabColHash;
#endif
  pTo->flags &= ~MEM_Dyn;
  if( pTo->flags&(MEM_Str|MEM_Blob) ){
    if( 0==(pFrom->flags&MEM_Static) ){
      pTo->flags |= MEM_Ephem;
      rc = sqlite3VdbeMemMakeWriteable(pTo);
    }
  }







<
<
<







 







<
<
<







 







<
<
<







930
931
932
933
934
935
936



937
938
939
940
941
942
943
...
950
951
952
953
954
955
956



957
958
959
960
961
962
963
...
967
968
969
970
971
972
973



974
975
976
977
978
979
980
      /* pMem is the register that is changing.  But also mark pX as
      ** undefined so that we can quickly detect the shallow-copy error */
      pX->flags = MEM_Undefined;
      pX->pScopyFrom = 0;
    }
  }
  pMem->pScopyFrom = 0;



}
#endif /* SQLITE_DEBUG */


/*
** Make an shallow copy of pFrom into pTo.  Prior contents of
** pTo are freed.  The pFrom->z field is not duplicated.  If
................................................................................
  sqlite3VdbeMemShallowCopy(pTo, pFrom, eType);
}
void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){
  assert( (pFrom->flags & MEM_RowSet)==0 );
  assert( pTo->db==pFrom->db );
  if( VdbeMemDynamic(pTo) ){ vdbeClrCopy(pTo,pFrom,srcType); return; }
  memcpy(pTo, pFrom, MEMCELLSIZE);



  if( (pFrom->flags&MEM_Static)==0 ){
    pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem);
    assert( srcType==MEM_Ephem || srcType==MEM_Static );
    pTo->flags |= srcType;
  }
}

................................................................................
*/
int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
  int rc = SQLITE_OK;

  assert( (pFrom->flags & MEM_RowSet)==0 );
  if( VdbeMemDynamic(pTo) ) vdbeMemClearExternAndSetNull(pTo);
  memcpy(pTo, pFrom, MEMCELLSIZE);



  pTo->flags &= ~MEM_Dyn;
  if( pTo->flags&(MEM_Str|MEM_Blob) ){
    if( 0==(pFrom->flags&MEM_Static) ){
      pTo->flags |= MEM_Ephem;
      rc = sqlite3VdbeMemMakeWriteable(pTo);
    }
  }