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Reimplement the linked list data structure used throughout the backend.

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In the past, we used a 'Lispy' linked list implementation: a "list" was
merely a pointer to the head node of the list. The problem with that
design is that it makes lappend() and length() linear time. This patch
fixes that problem (and others) by maintaining a count of the list
length and a pointer to the tail node along with each head node pointer.
A "list" is now a pointer to a structure containing some meta-data
about the list; the head and tail pointers in that structure refer
to ListCell structures that maintain the actual linked list of nodes.

The function names of the list API have also been changed to, I hope,
be more logically consistent. By default, the old function names are
still available; they will be disabled-by-default once the rest of
the tree has been updated to use the new API names.
This commit is contained in:
Neil Conway
2004-05-26 04:41:50 +00:00
parent 18d0d10563
commit d0b4399d81
125 changed files with 3639 additions and 3038 deletions
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87
src/backend/optimizer/path/indxpath.c
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@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.158 2004/03/27 00:24:28 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.159 2004/05/26 04:41:21 neilc Exp $
*
*-------------------------------------------------------------------------
*/
@ -121,7 +121,7 @@ void
create_index_paths(Query *root, RelOptInfo *rel)
{
Relids all_join_outerrelids = NULL;
List *ilist;
ListCell *ilist;
foreach(ilist, rel->indexlist)
{
@ -250,12 +250,12 @@ group_clauses_by_indexkey(RelOptInfo *rel, IndexOptInfo *index)
{
Oid curClass = classes[0];
FastList clausegroup;
List *i;
ListCell *l;
FastListInit(&clausegroup);
foreach(i, restrictinfo_list)
foreach(l, restrictinfo_list)
{
RestrictInfo *rinfo = (RestrictInfo *) lfirst(i);
RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
if (match_clause_to_indexcol(rel,
index,
@ -312,7 +312,7 @@ group_clauses_by_indexkey_for_join(Query *root,
Oid curClass = classes[0];
FastList clausegroup;
int numsources;
List *i;
ListCell *l;
FastListInit(&clausegroup);
@ -324,9 +324,9 @@ group_clauses_by_indexkey_for_join(Query *root,
* of a non-join clause if it appears after a join clause it is
* redundant with.
*/
foreach(i, rel->baserestrictinfo)
foreach(l, rel->baserestrictinfo)
{
RestrictInfo *rinfo = (RestrictInfo *) lfirst(i);
RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
/* Can't use pushed-down clauses in outer join */
if (isouterjoin && rinfo->is_pushed_down)
@ -344,11 +344,11 @@ group_clauses_by_indexkey_for_join(Query *root,
numsources = (FastListValue(&clausegroup) != NIL) ? 1 : 0;
/* Look for joinclauses that are usable with given outer_relids */
foreach(i, rel->joininfo)
foreach(l, rel->joininfo)
{
JoinInfo *joininfo = (JoinInfo *) lfirst(i);
JoinInfo *joininfo = (JoinInfo *) lfirst(l);
bool jfoundhere = false;
List *j;
ListCell *j;
if (!bms_is_subset(joininfo->unjoined_relids, outer_relids))
continue;
@ -448,7 +448,7 @@ group_clauses_by_indexkey_for_or(RelOptInfo *rel,
{
Oid curClass = classes[0];
FastList clausegroup;
List *item;
ListCell *item;
FastListInit(&clausegroup);
@ -511,7 +511,6 @@ group_clauses_by_indexkey_for_or(RelOptInfo *rel,
indexcol++;
classes++;
} while (!DoneMatchingIndexKeys(classes));
/* if OR clause was not used then forget it, per comments above */
@ -738,7 +737,7 @@ void
check_partial_indexes(Query *root, RelOptInfo *rel)
{
List *restrictinfo_list = rel->baserestrictinfo;
List *ilist;
ListCell *ilist;
foreach(ilist, rel->indexlist)
{
@ -772,7 +771,7 @@ check_partial_indexes(Query *root, RelOptInfo *rel)
static bool
pred_test(List *predicate_list, List *restrictinfo_list)
{
List *pred;
ListCell *pred;
/*
* Note: if Postgres tried to optimize queries by forming equivalence
@ -815,7 +814,7 @@ pred_test(List *predicate_list, List *restrictinfo_list)
static bool
pred_test_restrict_list(Expr *predicate, List *restrictinfo_list)
{
List *item;
ListCell *item;
foreach(item, restrictinfo_list)
{
@ -839,8 +838,8 @@ pred_test_restrict_list(Expr *predicate, List *restrictinfo_list)
static bool
pred_test_recurse_clause(Expr *predicate, Node *clause)
{
List *items,
*item;
List *items;
ListCell *item;
Assert(clause != NULL);
if (or_clause(clause))
@ -883,8 +882,8 @@ pred_test_recurse_clause(Expr *predicate, Node *clause)
static bool
pred_test_recurse_pred(Expr *predicate, Node *clause)
{
List *items,
*item;
List *items;
ListCell *item;
Assert(predicate != NULL);
if (or_clause((Node *) predicate))
@ -1360,13 +1359,13 @@ static Relids
indexable_outerrelids(RelOptInfo *rel, IndexOptInfo *index)
{
Relids outer_relids = NULL;
List *i;
ListCell *l;
foreach(i, rel->joininfo)
foreach(l, rel->joininfo)
{
JoinInfo *joininfo = (JoinInfo *) lfirst(i);
JoinInfo *joininfo = (JoinInfo *) lfirst(l);
bool match_found = false;
List *j;
ListCell *j;
/*
* Examine each joinclause in the JoinInfo node's list to see if
@ -1433,8 +1432,8 @@ best_inner_indexscan(Query *root, RelOptInfo *rel,
{
Path *cheapest = NULL;
bool isouterjoin;
List *ilist;
List *jlist;
ListCell *ilist;
ListCell *jlist;
InnerIndexscanInfo *info;
MemoryContext oldcontext;
@ -1538,7 +1537,7 @@ best_inner_indexscan(Query *root, RelOptInfo *rel,
}
}
if (jlist == NIL) /* failed to find a match? */
if (jlist == NULL) /* failed to find a match? */
{
List *clausegroups;
@ -1676,7 +1675,7 @@ List *
flatten_clausegroups_list(List *clausegroups)
{
List *allclauses = NIL;
List *l;
ListCell *l;
foreach(l, clausegroups)
{
@ -1697,7 +1696,7 @@ Expr *
make_expr_from_indexclauses(List *indexclauses)
{
List *orclauses = NIL;
List *orlist;
ListCell *orlist;
/* There's no such thing as an indexpath with zero scans */
Assert(indexclauses != NIL);
@ -1715,7 +1714,7 @@ make_expr_from_indexclauses(List *indexclauses)
if (length(orclauses) > 1)
return make_orclause(orclauses);
else
return (Expr *) lfirst(orclauses);
return (Expr *) linitial(orclauses);
}
@ -1768,23 +1767,23 @@ match_index_to_operand(Node *operand,
* could be avoided, at the cost of complicating all the callers
* of this routine; doesn't seem worth it.)
*/
List *indexprs;
ListCell *indexpr_item;
int i;
Node *indexkey;
indexprs = index->indexprs;
indexpr_item = list_head(index->indexprs);
for (i = 0; i < indexcol; i++)
{
if (index->indexkeys[i] == 0)
{
if (indexprs == NIL)
if (indexpr_item == NULL)
elog(ERROR, "wrong number of index expressions");
indexprs = lnext(indexprs);
indexpr_item = lnext(indexpr_item);
}
}
if (indexprs == NIL)
if (indexpr_item == NULL)
elog(ERROR, "wrong number of index expressions");
indexkey = (Node *) lfirst(indexprs);
indexkey = (Node *) lfirst(indexpr_item);
/*
* Does it match the operand? Again, strip any relabeling.
@ -2013,32 +2012,32 @@ List *
expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups)
{
FastList resultquals;
ListCell *clausegroup_item;
Oid *classes = index->classlist;
if (clausegroups == NIL)
return NIL;
FastListInit(&resultquals);
clausegroup_item = list_head(clausegroups);
do
{
Oid curClass = classes[0];
List *i;
ListCell *l;
foreach(i, (List *) lfirst(clausegroups))
foreach(l, (List *) lfirst(clausegroup_item))
{
RestrictInfo *rinfo = (RestrictInfo *) lfirst(i);
RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
FastConc(&resultquals,
expand_indexqual_condition(rinfo, curClass));
}
clausegroups = lnext(clausegroups);
clausegroup_item = lnext(clausegroup_item);
classes++;
} while (clausegroup_item != NULL && !DoneMatchingIndexKeys(classes));
} while (clausegroups != NIL && !DoneMatchingIndexKeys(classes));
Assert(clausegroups == NIL); /* else more groups than indexkeys... */
Assert(clausegroup_item == NULL); /* else more groups than indexkeys... */
return FastListValue(&resultquals);
}