/ Check-in [219b39e1]
Login

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

Overview
Comment:Rearrange the code in the VDBE to help out the C-compiler optimizer. And fix a harmless compiler warning.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | reuse-schema
Files: files | file ages | folders
SHA3-256: 219b39e149a0334b577e094e066e1ca2fe686b408468e9f196611490f3a82810
User & Date: drh 2019-02-13 14:06:56
Wiki:reuse-schema
References
2019-02-15
11:54
Revert the rearrangement of VDBE code in [219b39e14] so that vdbe.c matches trunk. Since the new call to sqlite3Init() in OP_ParseSchema was removed, the rearrangement no longer provides any performance advantage. check-in: 03c4f003 user: dan tags: reuse-schema
Context
2019-02-13
15:51
Fix a problem with the incrblob API and reusable schemas. check-in: 34f0f96f user: dan tags: reuse-schema
14:06
Rearrange the code in the VDBE to help out the C-compiler optimizer. And fix a harmless compiler warning. check-in: 219b39e1 user: drh tags: reuse-schema
13:48
Performance optimization in the VDBE, and a fix for a harmless compiler warning. Closed-Leaf check-in: e002666a user: drh tags: reuse-schema-vdbe-opt
08:40
Fix a problem with OPEN_REUSE_SCHEMA connections reloading the temp schema. check-in: 7c2ec2d4 user: dan tags: reuse-schema
Changes
Hide Diffs Unified Diffs Show Whitespace Changes Patch

Changes to src/status.c.

278
279
280
281
282
283
284
285
286
287
288
289
290
291
292

      sqlite3BtreeEnterAll(db);
      db->pnBytesFreed = &nByte;
      for(i=0; i<db->nDb; i++){
        Schema *pSchema = db->aDb[i].pSchema;
        if( ALWAYS(pSchema!=0) ){
          HashElem *p;
          int nStart = nByte;

          nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
              pSchema->tblHash.count 
            + pSchema->trigHash.count
            + pSchema->idxHash.count
            + pSchema->fkeyHash.count
          );







<







278
279
280
281
282
283
284

285
286
287
288
289
290
291

      sqlite3BtreeEnterAll(db);
      db->pnBytesFreed = &nByte;
      for(i=0; i<db->nDb; i++){
        Schema *pSchema = db->aDb[i].pSchema;
        if( ALWAYS(pSchema!=0) ){
          HashElem *p;


          nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
              pSchema->tblHash.count 
            + pSchema->trigHash.count
            + pSchema->idxHash.count
            + pSchema->fkeyHash.count
          );

Changes to src/vdbe.c.

407
408
409
410
411
412
413
















































































414
415
416
417
418
419
420
....
5753
5754
5755
5756
5757
5758
5759
5760
5761
5762
5763
5764
5765
5766
5767
5768
5769
5770
5771
5772
5773
5774
5775
5776
5777
5778
5779
5780
5781
5782
5783
5784
5785
5786
5787
5788
5789
5790
5791
5792
5793
5794
5795
5796
5797
5798
5799
5800
5801
5802
5803
5804
5805
5806
5807
5808
5809
5810
5811
5812
5813
5814
5815
5816
5817
5818
5819
5820
5821
5822
5823
5824
5825
5826
5827
5828
5829
5830
5831
5832
5833
5834
    return pMem->flags & (MEM_Int|MEM_Real);
  }
  if( pMem->flags & (MEM_Str|MEM_Blob) ){
    return computeNumericType(pMem);
  }
  return 0;
}

















































































#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){
................................................................................
** that match the WHERE clause P4.  If P4 is a NULL pointer, then the
** entire schema for P1 is reparsed.
**
** 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;
  int bRelease;

  /* Any prepared statement that invokes this opcode will hold mutexes
  ** on every btree.  This is a prerequisite for invoking 
  ** sqlite3InitCallback().
  */
#ifdef SQLITE_DEBUG
  for(iDb=0; iDb<db->nDb; iDb++){
    assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
  }
#endif

  iDb = pOp->p1;
  assert( iDb>=0 && iDb<db->nDb );
  assert( DbHasProperty(db, iDb, DB_SchemaLoaded) );

#ifndef SQLITE_OMIT_ALTERTABLE
  if( pOp->p4.z==0 ){
    assert( !IsReuseSchema(db) || iDb==1 );
    sqlite3SchemaClear(db->aDb[iDb].pSchema);
    db->mDbFlags &= ~DBFLAG_SchemaKnownOk;
    rc = sqlite3InitOne(db, iDb, &p->zErrMsg, INITFLAG_AlterTable);
    db->mDbFlags |= DBFLAG_SchemaChange;
    p->expired = 0;
  }else
#endif
  {
    zMaster = MASTER_NAME;
    initData.db = db;
    initData.iDb = iDb;
    initData.pzErrMsg = &p->zErrMsg;
    initData.mInitFlags = 0;
    zSql = sqlite3MPrintf(db,
       "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s ORDER BY rowid",
       db->aDb[iDb].zDbSName, zMaster, pOp->p4.z);
    if( zSql==0 ){
      rc = SQLITE_NOMEM_BKPT;
    }else{
      bRelease = sqlite3LockReusableSchema(db);
      if( IsReuseSchema(db) ){
        rc = sqlite3Init(db, &p->zErrMsg);
        if( rc ){
          sqlite3UnlockReusableSchema(db, bRelease);
          goto abort_due_to_error;
        }
      }
      assert( db->init.busy==0 );
      db->init.busy = 1;
      initData.rc = SQLITE_OK;
      initData.nInitRow = 0;
      assert( !db->mallocFailed );
      rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
      sqlite3UnlockReusableSchema(db, bRelease);
      if( rc==SQLITE_OK ) rc = initData.rc;
      if( rc==SQLITE_OK && initData.nInitRow==0 ){
        /* The OP_ParseSchema opcode with a non-NULL P4 argument should parse
        ** at least one SQL statement. Any less than that indicates that
        ** the sqlite_master table is corrupt. */
        rc = SQLITE_CORRUPT_BKPT;
      }
      sqlite3DbFreeNN(db, zSql);
      db->init.busy = 0;
    }
  }
  if( rc ){
    sqlite3ResetAllSchemasOfConnection(db);
    if( rc==SQLITE_NOMEM ){
      goto no_mem;
    }
    goto abort_due_to_error;
  }







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







 







|
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<







407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
....
5833
5834
5835
5836
5837
5838
5839
5840



































































5841
5842
5843
5844
5845
5846
5847
    return pMem->flags & (MEM_Int|MEM_Real);
  }
  if( pMem->flags & (MEM_Str|MEM_Blob) ){
    return computeNumericType(pMem);
  }
  return 0;
}

/*
** This is the implementation of the OP_ParseSchema opcode.  It is factored
** out of the main sqlite3VdbeExec() routine because it is not a performance-
** critical opcode and by factoring it out, it frees up registers in order
** to help the compiler optimizer do a better job with the other opcodes
** that are performance critical.
*/
static SQLITE_NOINLINE int parseSchemaOp(Vdbe *p, VdbeOp *pOp, sqlite3 *db){
  int iDb;
  const char *zMaster;
  char *zSql;
  InitData initData;
  int bRelease;
  int rc = SQLITE_OK;

  /* Any prepared statement that invokes this opcode will hold mutexes
  ** on every btree.  This is a prerequisite for invoking 
  ** sqlite3InitCallback().
  */
#ifdef SQLITE_DEBUG
  for(iDb=0; iDb<db->nDb; iDb++){
    assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
  }
#endif

  iDb = pOp->p1;
  assert( iDb>=0 && iDb<db->nDb );
  assert( DbHasProperty(db, iDb, DB_SchemaLoaded) );

#ifndef SQLITE_OMIT_ALTERTABLE
  if( pOp->p4.z==0 ){
    assert( !IsReuseSchema(db) || iDb==1 );
    sqlite3SchemaClear(db->aDb[iDb].pSchema);
    db->mDbFlags &= ~DBFLAG_SchemaKnownOk;
    rc = sqlite3InitOne(db, iDb, &p->zErrMsg, INITFLAG_AlterTable);
    db->mDbFlags |= DBFLAG_SchemaChange;
    p->expired = 0;
  }else
#endif
  {
    zMaster = MASTER_NAME;
    initData.db = db;
    initData.iDb = iDb;
    initData.pzErrMsg = &p->zErrMsg;
    initData.mInitFlags = 0;
    zSql = sqlite3MPrintf(db,
       "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s ORDER BY rowid",
       db->aDb[iDb].zDbSName, zMaster, pOp->p4.z);
    if( zSql==0 ){
      rc = SQLITE_NOMEM_BKPT;
    }else{
      bRelease = sqlite3LockReusableSchema(db);
      if( IsReuseSchema(db) ){
        rc = sqlite3Init(db, &p->zErrMsg);
        if( rc ){
          sqlite3UnlockReusableSchema(db, bRelease);
          return rc;
        }
      }
      assert( db->init.busy==0 );
      db->init.busy = 1;
      initData.rc = SQLITE_OK;
      initData.nInitRow = 0;
      assert( !db->mallocFailed );
      rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
      sqlite3UnlockReusableSchema(db, bRelease);
      if( rc==SQLITE_OK ) rc = initData.rc;
      if( rc==SQLITE_OK && initData.nInitRow==0 ){
        /* The OP_ParseSchema opcode with a non-NULL P4 argument should parse
        ** at least one SQL statement. Any less than that indicates that
        ** the sqlite_master table is corrupt. */
        rc = SQLITE_CORRUPT_BKPT;
      }
      sqlite3DbFreeNN(db, zSql);
      db->init.busy = 0;
    }
  }
  return rc;
}

#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){
................................................................................
** that match the WHERE clause P4.  If P4 is a NULL pointer, then the
** entire schema for P1 is reparsed.
**
** 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: {
  rc = parseSchemaOp(p, pOp, db);



































































  if( rc ){
    sqlite3ResetAllSchemasOfConnection(db);
    if( rc==SQLITE_NOMEM ){
      goto no_mem;
    }
    goto abort_due_to_error;
  }