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Overview
Comment:Avoid unnecessary calls to memset() for a small performance improvement.
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SHA1: 9e8c23acf74944a165c733682a956948b15bd401
User & Date: drh 2016-01-18 13:18:54
Context
2016-01-18
17:48
Add tests for fts5. Fix a crash that can occur in fts5 if the database content is corrupted. check-in: acaf4264 user: dan tags: trunk
13:18
Avoid unnecessary calls to memset() for a small performance improvement. check-in: 9e8c23ac user: drh tags: trunk
09:08
Add a debugging function to print human-readable versions of fts5 detail=none leaf pages. check-in: 8358af36 user: dan tags: trunk
Changes
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Changes to src/build.c.

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  SrcList *pList,     /* Append to this SrcList. NULL creates a new SrcList */
  Token *pTable,      /* Table to append */
  Token *pDatabase    /* Database of the table */
){
  struct SrcList_item *pItem;
  assert( pDatabase==0 || pTable!=0 );  /* Cannot have C without B */
  if( pList==0 ){
    pList = sqlite3DbMallocZero(db, sizeof(SrcList) );
    if( pList==0 ) return 0;
    pList->nAlloc = 1;

  }
  pList = sqlite3SrcListEnlarge(db, pList, 1, pList->nSrc);
  if( db->mallocFailed ){
    sqlite3SrcListDelete(db, pList);
    return 0;
  }
  pItem = &pList->a[pList->nSrc-1];







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  SrcList *pList,     /* Append to this SrcList. NULL creates a new SrcList */
  Token *pTable,      /* Table to append */
  Token *pDatabase    /* Database of the table */
){
  struct SrcList_item *pItem;
  assert( pDatabase==0 || pTable!=0 );  /* Cannot have C without B */
  if( pList==0 ){
    pList = sqlite3DbMallocRaw(db, sizeof(SrcList) );
    if( pList==0 ) return 0;
    pList->nAlloc = 1;
    pList->nSrc = 0;
  }
  pList = sqlite3SrcListEnlarge(db, pList, 1, pList->nSrc);
  if( db->mallocFailed ){
    sqlite3SrcListDelete(db, pList);
    return 0;
  }
  pItem = &pList->a[pList->nSrc-1];

Changes to src/expr.c.

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ExprList *sqlite3ExprListAppend(
  Parse *pParse,          /* Parsing context */
  ExprList *pList,        /* List to which to append. Might be NULL */
  Expr *pExpr             /* Expression to be appended. Might be NULL */
){
  sqlite3 *db = pParse->db;
  if( pList==0 ){
    pList = sqlite3DbMallocZero(db, sizeof(ExprList) );
    if( pList==0 ){
      goto no_mem;
    }

    pList->a = sqlite3DbMallocRaw(db, sizeof(pList->a[0]));
    if( pList->a==0 ) goto no_mem;
  }else if( (pList->nExpr & (pList->nExpr-1))==0 ){
    struct ExprList_item *a;
    assert( pList->nExpr>0 );
    a = sqlite3DbRealloc(db, pList->a, pList->nExpr*2*sizeof(pList->a[0]));
    if( a==0 ){







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ExprList *sqlite3ExprListAppend(
  Parse *pParse,          /* Parsing context */
  ExprList *pList,        /* List to which to append. Might be NULL */
  Expr *pExpr             /* Expression to be appended. Might be NULL */
){
  sqlite3 *db = pParse->db;
  if( pList==0 ){
    pList = sqlite3DbMallocRaw(db, sizeof(ExprList) );
    if( pList==0 ){
      goto no_mem;
    }
    pList->nExpr = 0;
    pList->a = sqlite3DbMallocRaw(db, sizeof(pList->a[0]));
    if( pList->a==0 ) goto no_mem;
  }else if( (pList->nExpr & (pList->nExpr-1))==0 ){
    struct ExprList_item *a;
    assert( pList->nExpr>0 );
    a = sqlite3DbRealloc(db, pList->a, pList->nExpr*2*sizeof(pList->a[0]));
    if( a==0 ){

Changes to src/select.c.

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}

/*
** Allocate a KeyInfo object sufficient for an index of N key columns and
** X extra columns.
*/
KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){
  KeyInfo *p = sqlite3DbMallocZero(0, 
                   sizeof(KeyInfo) + (N+X)*(sizeof(CollSeq*)+1));
  if( p ){
    p->aSortOrder = (u8*)&p->aColl[N+X];
    p->nField = (u16)N;
    p->nXField = (u16)X;
    p->enc = ENC(db);
    p->db = db;
    p->nRef = 1;

  }else{
    db->mallocFailed = 1;
  }
  return p;
}

/*







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}

/*
** Allocate a KeyInfo object sufficient for an index of N key columns and
** X extra columns.
*/
KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){
  int nExtra = (N+X)*(sizeof(CollSeq*)+1);
  KeyInfo *p = sqlite3Malloc(sizeof(KeyInfo) + nExtra);
  if( p ){
    p->aSortOrder = (u8*)&p->aColl[N+X];
    p->nField = (u16)N;
    p->nXField = (u16)X;
    p->enc = ENC(db);
    p->db = db;
    p->nRef = 1;
    memset(&p[1], 0, nExtra);
  }else{
    db->mallocFailed = 1;
  }
  return p;
}

/*