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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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60
src/backend/executor/nodeSubplan.c
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@ -7,7 +7,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/nodeSubplan.c,v 1.61 2004/03/17 01:02:23 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/nodeSubplan.c,v 1.62 2004/05/26 04:41:16 neilc Exp $
*
*-------------------------------------------------------------------------
*/
@ -212,8 +212,8 @@ ExecScanSubPlan(SubPlanState *node,
TupleTableSlot *slot;
Datum result;
bool found = false; /* TRUE if got at least one subplan tuple */
List *pvar;
List *lst;
ListCell *pvar;
ListCell *l;
ArrayBuildState *astate = NULL;
/*
@ -228,21 +228,19 @@ ExecScanSubPlan(SubPlanState *node,
* calculation we have to do is done in the parent econtext, since the
* Param values don't need to have per-query lifetime.)
*/
pvar = node->args;
foreach(lst, subplan->parParam)
Assert(length(subplan->parParam) == length(node->args));
forboth(l, subplan->parParam, pvar, node->args)
{
int paramid = lfirsti(lst);
int paramid = lfirst_int(l);
ParamExecData *prm = &(econtext->ecxt_param_exec_vals[paramid]);
Assert(pvar != NIL);
prm->value = ExecEvalExprSwitchContext((ExprState *) lfirst(pvar),
econtext,
&(prm->isnull),
NULL);
pvar = lnext(pvar);
planstate->chgParam = bms_add_member(planstate->chgParam, paramid);
}
Assert(pvar == NIL);
ExecReScan(planstate, NULL);
@ -278,7 +276,7 @@ ExecScanSubPlan(SubPlanState *node,
Datum rowresult = BoolGetDatum(!useOr);
bool rownull = false;
int col = 1;
List *plst;
ListCell *plst;
if (subLinkType == EXISTS_SUBLINK)
{
@ -343,11 +341,12 @@ ExecScanSubPlan(SubPlanState *node,
* For ALL, ANY, and MULTIEXPR sublinks, iterate over combining
* operators for columns of tuple.
*/
plst = subplan->paramIds;
foreach(lst, node->exprs)
Assert(length(node->exprs) == length(subplan->paramIds));
forboth(l, node->exprs, plst, subplan->paramIds)
{
ExprState *exprstate = (ExprState *) lfirst(lst);
int paramid = lfirsti(plst);
ExprState *exprstate = (ExprState *) lfirst(l);
int paramid = lfirst_int(plst);
ParamExecData *prmdata;
Datum expresult;
bool expnull;
@ -400,7 +399,6 @@ ExecScanSubPlan(SubPlanState *node,
}
}
plst = lnext(plst);
col++;
}
@ -559,7 +557,7 @@ buildSubPlanHash(SubPlanState *node)
HeapTuple tup = slot->val;
TupleDesc tdesc = slot->ttc_tupleDescriptor;
int col = 1;
List *plst;
ListCell *plst;
bool isnew;
/*
@ -737,7 +735,7 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
*/
if (subplan->setParam != NIL)
{
List *lst;
ListCell *lst;
foreach(lst, subplan->setParam)
{
@ -762,8 +760,8 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
List *lefttlist,
*righttlist,
*leftptlist,
*rightptlist,
*lexpr;
*rightptlist;
ListCell *lexpr;
/* We need a memory context to hold the hash table(s) */
node->tablecxt =
@ -815,7 +813,7 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
Assert(length(fstate->args) == 2);
/* Process lefthand argument */
exstate = (ExprState *) lfirst(fstate->args);
exstate = (ExprState *) linitial(fstate->args);
expr = exstate->expr;
tle = makeTargetEntry(makeResdom(i,
exprType((Node *) expr),
@ -914,7 +912,7 @@ ExecSetParamPlan(SubPlanState *node, ExprContext *econtext)
SubLinkType subLinkType = subplan->subLinkType;
MemoryContext oldcontext;
TupleTableSlot *slot;
List *lst;
ListCell *l;
bool found = false;
ArrayBuildState *astate = NULL;
@ -941,7 +939,7 @@ ExecSetParamPlan(SubPlanState *node, ExprContext *econtext)
if (subLinkType == EXISTS_SUBLINK)
{
/* There can be only one param... */
int paramid = lfirsti(subplan->setParam);
int paramid = linitial_int(subplan->setParam);
ParamExecData *prm = &(econtext->ecxt_param_exec_vals[paramid]);
prm->execPlan = NULL;
@ -992,9 +990,9 @@ ExecSetParamPlan(SubPlanState *node, ExprContext *econtext)
/*
* Now set all the setParam params from the columns of the tuple
*/
foreach(lst, subplan->setParam)
foreach(l, subplan->setParam)
{
int paramid = lfirsti(lst);
int paramid = lfirsti(l);
ParamExecData *prm = &(econtext->ecxt_param_exec_vals[paramid]);
prm->execPlan = NULL;
@ -1008,7 +1006,7 @@ ExecSetParamPlan(SubPlanState *node, ExprContext *econtext)
if (subLinkType == EXISTS_SUBLINK)
{
/* There can be only one param... */
int paramid = lfirsti(subplan->setParam);
int paramid = linitial_int(subplan->setParam);
ParamExecData *prm = &(econtext->ecxt_param_exec_vals[paramid]);
prm->execPlan = NULL;
@ -1017,9 +1015,9 @@ ExecSetParamPlan(SubPlanState *node, ExprContext *econtext)
}
else
{
foreach(lst, subplan->setParam)
foreach(l, subplan->setParam)
{
int paramid = lfirsti(lst);
int paramid = lfirsti(l);
ParamExecData *prm = &(econtext->ecxt_param_exec_vals[paramid]);
prm->execPlan = NULL;
@ -1031,7 +1029,7 @@ ExecSetParamPlan(SubPlanState *node, ExprContext *econtext)
else if (subLinkType == ARRAY_SUBLINK)
{
/* There can be only one param... */
int paramid = lfirsti(subplan->setParam);
int paramid = linitial_int(subplan->setParam);
ParamExecData *prm = &(econtext->ecxt_param_exec_vals[paramid]);
Assert(astate != NULL);
@ -1074,7 +1072,7 @@ ExecReScanSetParamPlan(SubPlanState *node, PlanState *parent)
PlanState *planstate = node->planstate;
SubPlan *subplan = (SubPlan *) node->xprstate.expr;
EState *estate = parent->state;
List *lst;
ListCell *l;
/* sanity checks */
if (subplan->parParam != NIL)
@ -1091,9 +1089,9 @@ ExecReScanSetParamPlan(SubPlanState *node, PlanState *parent)
/*
* Mark this subplan's output parameters as needing recalculation
*/
foreach(lst, subplan->setParam)
foreach(l, subplan->setParam)
{
int paramid = lfirsti(lst);
int paramid = lfirsti(l);
ParamExecData *prm = &(estate->es_param_exec_vals[paramid]);
prm->execPlan = node;