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Overview
Comment:Optimization to the out2Prerelease() helper routine in the VDBE engine.
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SHA1: 79298fe8c42f64b6a6110a70b84033873ac0630d
User & Date: drh 2015-10-15 17:31:41.009
Context
2015-10-15
18:04
Add the OP_IntCopy opcode - an optimized version of OP_SCopy that only works for integer values. (check-in: 3a2f73a492 user: drh tags: trunk)
17:31
Optimization to the out2Prerelease() helper routine in the VDBE engine. (check-in: 79298fe8c4 user: drh tags: trunk)
17:21
Remove a superfluous conditional from the memory allocation initialization. (check-in: 9ccf8f8d35 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/vdbe.c.
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  return 1;
}
#endif

/*
** Return the register of pOp->p2 after first preparing it to be
** overwritten with an integer value.
*/ 





static Mem *out2Prerelease(Vdbe *p, VdbeOp *pOp){
  Mem *pOut;
  assert( pOp->p2>0 );
  assert( pOp->p2<=(p->nMem-p->nCursor) );
  pOut = &p->aMem[pOp->p2];
  memAboutToChange(p, pOut);
  if( VdbeMemDynamic(pOut) ) sqlite3VdbeMemSetNull(pOut);


  pOut->flags = MEM_Int;
  return pOut;

}


/*
** Execute as much of a VDBE program as we can.
** This is the core of sqlite3_step().  
*/








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  return 1;
}
#endif

/*
** Return the register of pOp->p2 after first preparing it to be
** overwritten with an integer value.
*/
static SQLITE_NOINLINE Mem *out2PrereleaseWithClear(Mem *pOut){
  sqlite3VdbeMemSetNull(pOut);
  pOut->flags = MEM_Int;
  return pOut;
}
static Mem *out2Prerelease(Vdbe *p, VdbeOp *pOp){
  Mem *pOut;
  assert( pOp->p2>0 );
  assert( pOp->p2<=(p->nMem-p->nCursor) );
  pOut = &p->aMem[pOp->p2];
  memAboutToChange(p, pOut);
  if( VdbeMemDynamic(pOut) ){
    return out2PrereleaseWithClear(pOut);
  }else{
    pOut->flags = MEM_Int;
    return pOut;
  }
}


/*
** Execute as much of a VDBE program as we can.
** This is the core of sqlite3_step().  
*/
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