Initial pgindent and pgperltidy run for v13.

Includes some manual cleanup of places that pgindent messed up,
most of which weren't per project style anyway.

Notably, it seems some people didn't absorb the style rules of
commit c9d297751, because there were a bunch of new occurrences
of function calls with a newline just after the left paren, all
with faulty expectations about how the rest of the call would get
indented.

src/backend/access/nbtree/nbtpage.c

@@ -1566,7 +1566,8 @@ _bt_pagedel(Relation rel, Buffer leafbuf, TransactionId *oldestBtpoXact)
 				BTScanInsert itup_key;
 				ItemId		itemid;
 				IndexTuple	targetkey;
-				BlockNumber leftsib, leafblkno;
+				BlockNumber leftsib,
+							leafblkno;
 				Buffer		sleafbuf;
 
 				itemid = PageGetItemId(page, P_HIKEY);
@@ -1777,6 +1778,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
 
 #ifdef USE_ASSERT_CHECKING
+
 	/*
 	 * This is just an assertion because _bt_lock_subtree_parent should have
 	 * guaranteed tuple has the expected contents
@@ -2368,7 +2370,8 @@ _bt_lock_subtree_parent(Relation rel, BlockNumber child, BTStack stack,
 						Buffer *subtreeparent, OffsetNumber *poffset,
 						BlockNumber *topparent, BlockNumber *topparentrightsib)
 {
-	BlockNumber parent, leftsibparent;
+	BlockNumber parent,
+				leftsibparent;
 	OffsetNumber parentoffset,
 				maxoff;
 	Buffer		pbuf;
@@ -2439,9 +2442,9 @@ _bt_lock_subtree_parent(Relation rel, BlockNumber child, BTStack stack,
 	/*
 	 * Now make sure that the parent deletion is itself safe by examining the
 	 * child's grandparent page.  Recurse, passing the parent page as the
-	 * child page (child's grandparent is the parent on the next level up).
-	 * If parent deletion is unsafe, then child deletion must also be unsafe
-	 * (in which case caller cannot delete any pages at all).
+	 * child page (child's grandparent is the parent on the next level up). If
+	 * parent deletion is unsafe, then child deletion must also be unsafe (in
+	 * which case caller cannot delete any pages at all).
 	 */
 	*topparent = parent;
 	*topparentrightsib = opaque->btpo_next;

src/backend/access/nbtree/nbtree.c

@@ -1091,7 +1091,8 @@ btvacuumpage(BTVacState *vstate, BlockNumber scanblkno)
 	void	   *callback_state = vstate->callback_state;
 	Relation	rel = info->index;
 	bool		attempt_pagedel;
-	BlockNumber blkno, backtrack_to;
+	BlockNumber blkno,
+				backtrack_to;
 	Buffer		buf;
 	Page		page;
 	BTPageOpaque opaque;

src/backend/access/nbtree/nbtsearch.c

@@ -156,11 +156,10 @@ _bt_search(Relation rel, BTScanInsert key, Buffer *bufP, int access,
 
 		/*
 		 * We need to save the location of the pivot tuple we chose in the
-		 * parent page on a stack.  If we need to split a page, we'll use
-		 * the stack to work back up to its parent page.  If caller ends up
-		 * splitting a page one level down, it usually ends up inserting a
-		 * new pivot tuple/downlink immediately after the location recorded
-		 * here.
+		 * parent page on a stack.  If we need to split a page, we'll use the
+		 * stack to work back up to its parent page.  If caller ends up
+		 * splitting a page one level down, it usually ends up inserting a new
+		 * pivot tuple/downlink immediately after the location recorded here.
 		 */
 		new_stack = (BTStack) palloc(sizeof(BTStackData));
 		new_stack->bts_blkno = par_blkno;

src/backend/access/nbtree/nbtsplitloc.c

@@ -72,7 +72,7 @@ static bool _bt_afternewitemoff(FindSplitData *state, OffsetNumber maxoff,
 static bool _bt_adjacenthtid(ItemPointer lowhtid, ItemPointer highhtid);
 static OffsetNumber _bt_bestsplitloc(FindSplitData *state, int perfectpenalty,
 									 bool *newitemonleft, FindSplitStrat strategy);
-static int _bt_defaultinterval(FindSplitData *state);
+static int	_bt_defaultinterval(FindSplitData *state);
 static int	_bt_strategy(FindSplitData *state, SplitPoint *leftpage,
 						 SplitPoint *rightpage, FindSplitStrat *strategy);
 static void _bt_interval_edges(FindSplitData *state,