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Overview
Comment:Free up the MEM_Frame bit in Mem.flags object. Store VdbeFrame objects as MEM_Blob with a special Mem.xDel pointer instead.
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SHA3-256: 62db5fd47660bbc4fcf2c6d4a6c5a3077f12c6442a128d22b66b789a0409ef32
User & Date: drh 2018-08-29 18:47:22
Context
2018-08-29
20:24
Also free up the MEM_RowSet bit in the Mem.flags field and have RowSet objects be destroyed using Mem.xDel. This change results in faster code. check-in: f48e9feb3f user: drh tags: trunk
18:47
Free up the MEM_Frame bit in Mem.flags object. Store VdbeFrame objects as MEM_Blob with a special Mem.xDel pointer instead. check-in: 62db5fd476 user: drh tags: trunk
15:50
Add the geopoly_group_bbox() aggregate function to the Geopoly module. check-in: 2d4debccbc user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/vdbe.c.

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    goto abort_due_to_error;
  }

  /* 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;
    assert( nMem>0 );
................................................................................
              + pProgram->nCsr * sizeof(VdbeCursor*)
              + (pProgram->nOp + 7)/8;
    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 = (int)(pOp - aOp);
    pFrame->aMem = p->aMem;
    pFrame->nMem = p->nMem;
................................................................................
    pFrame->nCursor = p->nCursor;
    pFrame->aOp = p->aOp;
    pFrame->nOp = p->nOp;
    pFrame->token = pProgram->token;
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
    pFrame->anExec = p->anExec;
#endif




    pEnd = &VdbeFrameMem(pFrame)[pFrame->nChildMem];
    for(pMem=VdbeFrameMem(pFrame); pMem!=pEnd; pMem++){
      pMem->flags = MEM_Undefined;
      pMem->db = db;
    }
  }else{
    pFrame = pRt->u.pFrame;

    assert( pProgram->nMem+pProgram->nCsr==pFrame->nChildMem 
        || (pProgram->nCsr==0 && pProgram->nMem+1==pFrame->nChildMem) );
    assert( pProgram->nCsr==pFrame->nChildCsr );
    assert( (int)(pOp - aOp)==pFrame->pc );
  }

  p->nFrame++;







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    goto abort_due_to_error;
  }

  /* 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_Blob)==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;
    assert( nMem>0 );
................................................................................
              + pProgram->nCsr * sizeof(VdbeCursor*)
              + (pProgram->nOp + 7)/8;
    pFrame = sqlite3DbMallocZero(db, nByte);
    if( !pFrame ){
      goto no_mem;
    }
    sqlite3VdbeMemRelease(pRt);
    pRt->flags = MEM_Blob|MEM_Dyn;
    pRt->z = (char*)pFrame;
    pRt->n = nByte;
    pRt->xDel = sqlite3VdbeFrameMemDel;

    pFrame->v = p;
    pFrame->nChildMem = nMem;
    pFrame->nChildCsr = pProgram->nCsr;
    pFrame->pc = (int)(pOp - aOp);
    pFrame->aMem = p->aMem;
    pFrame->nMem = p->nMem;
................................................................................
    pFrame->nCursor = p->nCursor;
    pFrame->aOp = p->aOp;
    pFrame->nOp = p->nOp;
    pFrame->token = pProgram->token;
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
    pFrame->anExec = p->anExec;
#endif
#ifdef SQLITE_DEBUG
    pFrame->iFrameMagic = SQLITE_FRAME_MAGIC;
#endif

    pEnd = &VdbeFrameMem(pFrame)[pFrame->nChildMem];
    for(pMem=VdbeFrameMem(pFrame); pMem!=pEnd; pMem++){
      pMem->flags = MEM_Undefined;
      pMem->db = db;
    }
  }else{
    pFrame = (VdbeFrame*)pRt->z;
    assert( pRt->xDel==sqlite3VdbeFrameMemDel );
    assert( pProgram->nMem+pProgram->nCsr==pFrame->nChildMem 
        || (pProgram->nCsr==0 && pProgram->nMem+1==pFrame->nChildMem) );
    assert( pProgram->nCsr==pFrame->nChildCsr );
    assert( (int)(pOp - aOp)==pFrame->pc );
  }

  p->nFrame++;

Changes to src/vdbeInt.h.

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  i64 *anExec;            /* Event counters from parent frame */
  Mem *aMem;              /* Array of memory cells for parent frame */
  VdbeCursor **apCsr;     /* Array of Vdbe cursors for parent frame */
  u8 *aOnce;              /* Bitmask used by OP_Once */
  void *token;            /* Copy of SubProgram.token */
  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
  AuxData *pAuxData;      /* Linked list of auxdata allocations */



  int nCursor;            /* Number of entries in apCsr */
  int pc;                 /* Program Counter in parent (calling) frame */
  int nOp;                /* Size of aOp array */
  int nMem;               /* Number of entries in aMem */
  int nChildMem;          /* Number of memory cells for child frame */
  int nChildCsr;          /* Number of cursors for child frame */
  int nChange;            /* Statement changes (Vdbe.nChange)     */
  int nDbChange;          /* Value of db->nChange */
};








#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])

/*
** Internally, the vdbe manipulates nearly all SQL values as Mem
** structures. Each Mem struct may cache multiple representations (string,
** integer etc.) of the same value.
*/
................................................................................
  union MemValue {
    double r;           /* Real value used when MEM_Real is set in flags */
    i64 i;              /* Integer value used when MEM_Int is set in flags */
    int nZero;          /* Extra zero bytes when MEM_Zero and MEM_Blob set */
    const char *zPType; /* Pointer type when MEM_Term|MEM_Subtype|MEM_Null */
    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
  } u;
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
  u8  eSubtype;       /* Subtype for this value */
  int n;              /* Number of characters in string value, excluding '\0' */
  char *z;            /* String or BLOB value */
  /* ShallowCopy only needs to copy the information above */
................................................................................
#define MEM_Null      0x0001   /* Value is NULL (or a pointer) */
#define MEM_Str       0x0002   /* Value is a string */
#define MEM_Int       0x0004   /* Value is an integer */
#define MEM_Real      0x0008   /* Value is a real number */
#define MEM_Blob      0x0010   /* Value is a BLOB */
#define MEM_AffMask   0x001f   /* Mask of affinity bits */
#define MEM_RowSet    0x0020   /* Value is a RowSet object */
#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
#define MEM_Undefined 0x0080   /* Value is undefined */
#define MEM_Cleared   0x0100   /* NULL set by OP_Null, not from data */
#define MEM_TypeMask  0xc1ff   /* Mask of type bits */


/* Whenever Mem contains a valid string or blob representation, one of
** the following flags must be set to determine the memory management
................................................................................
  #define MEM_Zero 0x0000
#endif

/* Return TRUE if Mem X contains dynamically allocated content - anything
** that needs to be deallocated to avoid a leak.
*/
#define VdbeMemDynamic(X)  \
  (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)

/*
** Clear any existing type flags from a Mem and replace them with f
*/
#define MemSetTypeFlag(p, f) \
   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)

................................................................................
#ifndef SQLITE_OMIT_WINDOWFUNC
int sqlite3VdbeMemAggValue(Mem*, Mem*, FuncDef*);
#endif
const char *sqlite3OpcodeName(int);
int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
int sqlite3VdbeMemClearAndResize(Mem *pMem, int n);
int sqlite3VdbeCloseStatement(Vdbe *, int);




void sqlite3VdbeFrameDelete(VdbeFrame*);
int sqlite3VdbeFrameRestore(VdbeFrame *);
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
void sqlite3VdbePreUpdateHook(Vdbe*,VdbeCursor*,int,const char*,Table*,i64,int);
#endif
int sqlite3VdbeTransferError(Vdbe *p);

int sqlite3VdbeSorterInit(sqlite3 *, int, VdbeCursor *);







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  i64 *anExec;            /* Event counters from parent frame */
  Mem *aMem;              /* Array of memory cells for parent frame */
  VdbeCursor **apCsr;     /* Array of Vdbe cursors for parent frame */
  u8 *aOnce;              /* Bitmask used by OP_Once */
  void *token;            /* Copy of SubProgram.token */
  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
  AuxData *pAuxData;      /* Linked list of auxdata allocations */
#if SQLITE_DEBUG
  u32 iFrameMagic;        /* magic number for sanity checking */
#endif
  int nCursor;            /* Number of entries in apCsr */
  int pc;                 /* Program Counter in parent (calling) frame */
  int nOp;                /* Size of aOp array */
  int nMem;               /* Number of entries in aMem */
  int nChildMem;          /* Number of memory cells for child frame */
  int nChildCsr;          /* Number of cursors for child frame */
  int nChange;            /* Statement changes (Vdbe.nChange)     */
  int nDbChange;          /* Value of db->nChange */
};

/* Magic number for sanity checking on VdbeFrame objects */
#define SQLITE_FRAME_MAGIC 0x879fb71e

/*
** Return a pointer to the array of registers allocated for use
** by a VdbeFrame.
*/
#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])

/*
** Internally, the vdbe manipulates nearly all SQL values as Mem
** structures. Each Mem struct may cache multiple representations (string,
** integer etc.) of the same value.
*/
................................................................................
  union MemValue {
    double r;           /* Real value used when MEM_Real is set in flags */
    i64 i;              /* Integer value used when MEM_Int is set in flags */
    int nZero;          /* Extra zero bytes when MEM_Zero and MEM_Blob set */
    const char *zPType; /* Pointer type when MEM_Term|MEM_Subtype|MEM_Null */
    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */

  } u;
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
  u8  eSubtype;       /* Subtype for this value */
  int n;              /* Number of characters in string value, excluding '\0' */
  char *z;            /* String or BLOB value */
  /* ShallowCopy only needs to copy the information above */
................................................................................
#define MEM_Null      0x0001   /* Value is NULL (or a pointer) */
#define MEM_Str       0x0002   /* Value is a string */
#define MEM_Int       0x0004   /* Value is an integer */
#define MEM_Real      0x0008   /* Value is a real number */
#define MEM_Blob      0x0010   /* Value is a BLOB */
#define MEM_AffMask   0x001f   /* Mask of affinity bits */
#define MEM_RowSet    0x0020   /* Value is a RowSet object */
/* Available          0x0040   */
#define MEM_Undefined 0x0080   /* Value is undefined */
#define MEM_Cleared   0x0100   /* NULL set by OP_Null, not from data */
#define MEM_TypeMask  0xc1ff   /* Mask of type bits */


/* Whenever Mem contains a valid string or blob representation, one of
** the following flags must be set to determine the memory management
................................................................................
  #define MEM_Zero 0x0000
#endif

/* Return TRUE if Mem X contains dynamically allocated content - anything
** that needs to be deallocated to avoid a leak.
*/
#define VdbeMemDynamic(X)  \
  (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet))!=0)

/*
** Clear any existing type flags from a Mem and replace them with f
*/
#define MemSetTypeFlag(p, f) \
   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)

................................................................................
#ifndef SQLITE_OMIT_WINDOWFUNC
int sqlite3VdbeMemAggValue(Mem*, Mem*, FuncDef*);
#endif
const char *sqlite3OpcodeName(int);
int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
int sqlite3VdbeMemClearAndResize(Mem *pMem, int n);
int sqlite3VdbeCloseStatement(Vdbe *, int);
#ifdef SQLITE_DEBUG
int sqlite3VdbeFrameIsValid(VdbeFrame*);
#endif
void sqlite3VdbeFrameMemDel(void*);      /* Destructor on Mem */
void sqlite3VdbeFrameDelete(VdbeFrame*); /* Actually deletes the Frame */
int sqlite3VdbeFrameRestore(VdbeFrame *);
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
void sqlite3VdbePreUpdateHook(Vdbe*,VdbeCursor*,int,const char*,Table*,i64,int);
#endif
int sqlite3VdbeTransferError(Vdbe *p);

int sqlite3VdbeSorterInit(sqlite3 *, int, VdbeCursor *);

Changes to src/vdbeaux.c.

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      ** sqlite3MemRelease() were called from here. With -O2, this jumps
      ** to 6.6 percent. The test case is inserting 1000 rows into a table 
      ** with no indexes using a single prepared INSERT statement, bind() 
      ** and reset(). Inserts are grouped into a transaction.
      */
      testcase( p->flags & MEM_Agg );
      testcase( p->flags & MEM_Dyn );
      testcase( p->flags & MEM_Frame );
      testcase( p->flags & MEM_RowSet );
      if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_RowSet) ){
        sqlite3VdbeMemRelease(p);
      }else if( p->szMalloc ){
        sqlite3DbFreeNN(db, p->zMalloc);
        p->szMalloc = 0;
      }

      p->flags = MEM_Undefined;
    }while( (++p)<pEnd );
  }
}






























/*
** Delete a VdbeFrame object and its contents. VdbeFrame objects are
** allocated by the OP_Program opcode in sqlite3VdbeExec().
*/
void sqlite3VdbeFrameDelete(VdbeFrame *p){
  int i;
  Mem *aMem = VdbeFrameMem(p);
  VdbeCursor **apCsr = (VdbeCursor **)&aMem[p->nChildMem];

  for(i=0; i<p->nChildCsr; i++){
    sqlite3VdbeFreeCursor(p->v, apCsr[i]);
  }
  releaseMemArray(aMem, p->nChildMem);
  sqlite3VdbeDeleteAuxData(p->v->db, &p->pAuxData, -1, 0);
  sqlite3DbFree(p->v->db, p);
}







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      ** sqlite3MemRelease() were called from here. With -O2, this jumps
      ** to 6.6 percent. The test case is inserting 1000 rows into a table 
      ** with no indexes using a single prepared INSERT statement, bind() 
      ** and reset(). Inserts are grouped into a transaction.
      */
      testcase( p->flags & MEM_Agg );
      testcase( p->flags & MEM_Dyn );
      testcase( p->xDel==sqlite3VdbeFrameMemDel );
      testcase( p->flags & MEM_RowSet );
      if( p->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet) ){
        sqlite3VdbeMemRelease(p);
      }else if( p->szMalloc ){
        sqlite3DbFreeNN(db, p->zMalloc);
        p->szMalloc = 0;
      }

      p->flags = MEM_Undefined;
    }while( (++p)<pEnd );
  }
}

#ifdef SQLITE_DEBUG
/*
** Verify that pFrame is a valid VdbeFrame pointer.  Return true if it is
** and false if something is wrong.
**
** This routine is intended for use inside of assert() statements only.
*/
int sqlite3VdbeFrameIsValid(VdbeFrame *pFrame){
  if( pFrame->iFrameMagic!=SQLITE_FRAME_MAGIC ) return 0;
  return 1;
}
#endif


/*
** This is a destructor on a Mem object (which is really an sqlite3_value)
** that deletes the Frame object that is attached to it as a blob.
**
** This routine does not delete the Frame right away.  It merely adds the
** frame to a list of frames to be deleted when the Vdbe halts.
*/
void sqlite3VdbeFrameMemDel(void *pArg){
  VdbeFrame *pFrame = (VdbeFrame*)pArg;
  assert( sqlite3VdbeFrameIsValid(pFrame) );
  pFrame->pParent = pFrame->v->pDelFrame;
  pFrame->v->pDelFrame = pFrame;
}


/*
** Delete a VdbeFrame object and its contents. VdbeFrame objects are
** allocated by the OP_Program opcode in sqlite3VdbeExec().
*/
void sqlite3VdbeFrameDelete(VdbeFrame *p){
  int i;
  Mem *aMem = VdbeFrameMem(p);
  VdbeCursor **apCsr = (VdbeCursor **)&aMem[p->nChildMem];
  assert( sqlite3VdbeFrameIsValid(p) );
  for(i=0; i<p->nChildCsr; i++){
    sqlite3VdbeFreeCursor(p->v, apCsr[i]);
  }
  releaseMemArray(aMem, p->nChildMem);
  sqlite3VdbeDeleteAuxData(p->v->db, &p->pAuxData, -1, 0);
  sqlite3DbFree(p->v->db, p);
}

Changes to src/vdbemem.c.

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  /* Cannot be both MEM_Int and MEM_Real at the same time */
  assert( (p->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) );

  if( p->flags & MEM_Null ){
    /* Cannot be both MEM_Null and some other type */
    assert( (p->flags & (MEM_Int|MEM_Real|MEM_Str|MEM_Blob
                         |MEM_RowSet|MEM_Frame|MEM_Agg))==0 );

    /* If MEM_Null is set, then either the value is a pure NULL (the usual
    ** case) or it is a pointer set using sqlite3_bind_pointer() or
    ** sqlite3_result_pointer().  If a pointer, then MEM_Term must also be
    ** set.
    */
    if( (p->flags & (MEM_Term|MEM_Subtype))==(MEM_Term|MEM_Subtype) ){
................................................................................
  }
  if( p->flags&MEM_Dyn ){
    assert( (p->flags&MEM_RowSet)==0 );
    assert( p->xDel!=SQLITE_DYNAMIC && p->xDel!=0 );
    p->xDel((void *)p->z);
  }else if( p->flags&MEM_RowSet ){
    sqlite3RowSetClear(p->u.pRowSet);
  }else if( p->flags&MEM_Frame ){
    VdbeFrame *pFrame = p->u.pFrame;
    pFrame->pParent = pFrame->v->pDelFrame;
    pFrame->v->pDelFrame = pFrame;
  }
  p->flags = MEM_Null;
}

/*
** Release memory held by the Mem p, both external memory cleared
** by p->xDel and memory in p->zMalloc.







|







 







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  /* Cannot be both MEM_Int and MEM_Real at the same time */
  assert( (p->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) );

  if( p->flags & MEM_Null ){
    /* Cannot be both MEM_Null and some other type */
    assert( (p->flags & (MEM_Int|MEM_Real|MEM_Str|MEM_Blob
                         |MEM_RowSet|MEM_Agg))==0 );

    /* If MEM_Null is set, then either the value is a pure NULL (the usual
    ** case) or it is a pointer set using sqlite3_bind_pointer() or
    ** sqlite3_result_pointer().  If a pointer, then MEM_Term must also be
    ** set.
    */
    if( (p->flags & (MEM_Term|MEM_Subtype))==(MEM_Term|MEM_Subtype) ){
................................................................................
  }
  if( p->flags&MEM_Dyn ){
    assert( (p->flags&MEM_RowSet)==0 );
    assert( p->xDel!=SQLITE_DYNAMIC && p->xDel!=0 );
    p->xDel((void *)p->z);
  }else if( p->flags&MEM_RowSet ){
    sqlite3RowSetClear(p->u.pRowSet);




  }
  p->flags = MEM_Null;
}

/*
** Release memory held by the Mem p, both external memory cleared
** by p->xDel and memory in p->zMalloc.