Convert planner's AggInfo and AggTransInfo structs to proper Nodes.

This is mostly just to get outfuncs.c support for them, so that
the agginfos and aggtransinfos lists can be dumped when dumping
the contents of PlannerInfo.

While here, improve some related comments; notably, clean up
obsolete comments left over from when preprocess_minmax_aggregates
had to make its own scan of the query tree.

Discussion: https://postgr.es/m/742479.1658160504@sss.pgh.pa.us

1 files changed, 26 insertions, 16 deletions

diff --git a/src/include/nodes/pathnodes.h b/src/include/nodes/pathnodes.h
index 69ba254372d..e650af5ff29 100644
--- a/src/include/nodes/pathnodes.h
+++ b/src/include/nodes/pathnodes.h
@@ -442,15 +442,15 @@ struct PlannerInfo
 	 * Information about aggregates. Filled by preprocess_aggrefs().
 	 */
 	/* AggInfo structs */
-	List	   *agginfos pg_node_attr(read_write_ignore);
+	List	   *agginfos;
 	/* AggTransInfo structs */
-	List	   *aggtransinfos pg_node_attr(read_write_ignore);
-	/* number w/ DISTINCT/ORDER BY/WITHIN GROUP */
-	int			numOrderedAggs pg_node_attr(read_write_ignore);
+	List	   *aggtransinfos;
+	/* number of aggs with DISTINCT/ORDER BY/WITHIN GROUP */
+	int			numOrderedAggs;
 	/* does any agg not support partial mode? */
-	bool		hasNonPartialAggs pg_node_attr(read_write_ignore);
+	bool		hasNonPartialAggs;
 	/* is any partial agg non-serializable? */
-	bool		hasNonSerialAggs pg_node_attr(read_write_ignore);
+	bool		hasNonSerialAggs;
 
 	/*
 	 * These fields are used only when hasRecursion is true:
@@ -3121,6 +3121,10 @@ typedef struct JoinCostWorkspace
  */
 typedef struct AggInfo
 {
+	pg_node_attr(no_copy_equal, no_read)
+
+	NodeTag		type;
+
 	/*
 	 * Link to an Aggref expr this state value is for.
 	 *
@@ -3129,6 +3133,7 @@ typedef struct AggInfo
 	 */
 	Aggref	   *representative_aggref;
 
+	/* Transition state number for this aggregate */
 	int			transno;
 
 	/*
@@ -3137,9 +3142,8 @@ typedef struct AggInfo
 	 */
 	bool		shareable;
 
-	/* Oid of the final function or InvalidOid */
+	/* Oid of the final function, or InvalidOid if none */
 	Oid			finalfn_oid;
-
 } AggInfo;
 
 /*
@@ -3151,34 +3155,40 @@ typedef struct AggInfo
  */
 typedef struct AggTransInfo
 {
+	pg_node_attr(no_copy_equal, no_read)
+
+	NodeTag		type;
+
+	/* Inputs for this transition state */
 	List	   *args;
 	Expr	   *aggfilter;
 
 	/* Oid of the state transition function */
 	Oid			transfn_oid;
 
-	/* Oid of the serialization function or InvalidOid */
+	/* Oid of the serialization function, or InvalidOid if none */
 	Oid			serialfn_oid;
 
-	/* Oid of the deserialization function or InvalidOid */
+	/* Oid of the deserialization function, or InvalidOid if none */
 	Oid			deserialfn_oid;
 
-	/* Oid of the combine function or InvalidOid */
+	/* Oid of the combine function, or InvalidOid if none */
 	Oid			combinefn_oid;
 
 	/* Oid of state value's datatype */
 	Oid			aggtranstype;
+
+	/* Additional data about transtype */
 	int32		aggtranstypmod;
 	int			transtypeLen;
 	bool		transtypeByVal;
+
+	/* Space-consumption estimate */
 	int32		aggtransspace;
 
-	/*
-	 * initial value from pg_aggregate entry
-	 */
-	Datum		initValue;
+	/* Initial value from pg_aggregate entry */
+	Datum		initValue pg_node_attr(read_write_ignore);
 	bool		initValueIsNull;
-
 } AggTransInfo;
 
 #endif							/* PATHNODES_H */