Refactor pull_var_clause's API to make it less tedious to extend.

In commit 1d97c19a0f748e94 and later c1d9579dd8bf3c92, we extended
pull_var_clause's API by adding enum-type arguments.  That's sort of a pain
to maintain, though, because it means every time we add a new behavior we
must touch every last one of the call sites, even if there's a reasonable
default behavior that most of them could use.  Let's switch over to using a
bitmask of flags, instead; that seems more maintainable and might save a
nanosecond or two as well.  This commit changes no behavior in itself,
though I'm going to follow it up with one that does add a new behavior.

In passing, remove flatten_tlist(), which has not been used since 9.1
and would otherwise need the same API changes.

Removing these enums means that optimizer/tlist.h no longer needs to
depend on optimizer/var.h.  Changing that caused a number of C files to
need addition of #include "optimizer/var.h" (probably we can thank old
runs of pgrminclude for that); but on balance it seems like a good change
anyway.

2 files changed, 9 insertions, 17 deletions

diff --git a/src/include/optimizer/tlist.h b/src/include/optimizer/tlist.h
index a60e10278c..2c79a80391 100644
--- a/src/include/optimizer/tlist.h
+++ b/src/include/optimizer/tlist.h
@@ -14,14 +14,12 @@
 #ifndef TLIST_H
 #define TLIST_H
 
-#include "optimizer/var.h"
+#include "nodes/relation.h"
 
 
 extern TargetEntry *tlist_member(Node *node, List *targetlist);
 extern TargetEntry *tlist_member_ignore_relabel(Node *node, List *targetlist);
 
-extern List *flatten_tlist(List *tlist, PVCAggregateBehavior aggbehavior,
-			  PVCPlaceHolderBehavior phbehavior);
 extern List *add_to_flat_tlist(List *tlist, List *exprs);
 
 extern List *get_tlist_exprs(List *tlist, bool includeJunk);
diff --git a/src/include/optimizer/var.h b/src/include/optimizer/var.h
index aded1fe4df..d1b0978b97 100644
--- a/src/include/optimizer/var.h
+++ b/src/include/optimizer/var.h
@@ -16,19 +16,14 @@
 
 #include "nodes/relation.h"
 
-typedef enum
-{
-	PVC_REJECT_AGGREGATES,		/* throw error if Aggref found */
-	PVC_INCLUDE_AGGREGATES,		/* include Aggrefs in output list */
-	PVC_RECURSE_AGGREGATES		/* recurse into Aggref arguments */
-} PVCAggregateBehavior;
+/* Bits that can be OR'd into the flags argument of pull_var_clause() */
+#define PVC_INCLUDE_AGGREGATES	0x0001	/* include Aggrefs in output list */
+#define PVC_RECURSE_AGGREGATES	0x0002	/* recurse into Aggref arguments */
+#define PVC_INCLUDE_PLACEHOLDERS	0x0004		/* include PlaceHolderVars in
+												 * output list */
+#define PVC_RECURSE_PLACEHOLDERS	0x0008		/* recurse into PlaceHolderVar
+												 * arguments */
 
-typedef enum
-{
-	PVC_REJECT_PLACEHOLDERS,	/* throw error if PlaceHolderVar found */
-	PVC_INCLUDE_PLACEHOLDERS,	/* include PlaceHolderVars in output list */
-	PVC_RECURSE_PLACEHOLDERS	/* recurse into PlaceHolderVar arguments */
-} PVCPlaceHolderBehavior;
 
 extern Relids pull_varnos(Node *node);
 extern Relids pull_varnos_of_level(Node *node, int levelsup);
@@ -37,8 +32,7 @@ extern List *pull_vars_of_level(Node *node, int levelsup);
 extern bool contain_var_clause(Node *node);
 extern bool contain_vars_of_level(Node *node, int levelsup);
 extern int	locate_var_of_level(Node *node, int levelsup);
-extern List *pull_var_clause(Node *node, PVCAggregateBehavior aggbehavior,
-				PVCPlaceHolderBehavior phbehavior);
+extern List *pull_var_clause(Node *node, int flags);
 extern Node *flatten_join_alias_vars(PlannerInfo *root, Node *node);
 
 #endif   /* VAR_H */