Pass ItemPointer not HeapTuple to IndexBuildCallback.

Not all AMs use HeapTuples internally, making it inconvenient to pass
a HeapTuple. As the index callbacks really only need the TID, not the
full tuple, modify callback to only take ItemPointer.

Author: Ashwin Agrawal
Reviewed-By: Andres Freund
Discussion: https://postgr.es/m/CALfoeis6=8ehuR=VNtHvj3z16cYfCwPdTcpaxU+sfSUJ5QgR3g@mail.gmail.com

contrib/amcheck/verify_nbtree.c

@@ -140,7 +140,7 @@ static BTScanInsert bt_right_page_check_scankey(BtreeCheckState *state);
 static void bt_downlink_check(BtreeCheckState *state, BTScanInsert targetkey,
 							  BlockNumber childblock);
 static void bt_downlink_missing_check(BtreeCheckState *state);
-static void bt_tuple_present_callback(Relation index, HeapTuple htup,
+static void bt_tuple_present_callback(Relation index, ItemPointer tid,
 									  Datum *values, bool *isnull,
 									  bool tupleIsAlive, void *checkstate);
 static IndexTuple bt_normalize_tuple(BtreeCheckState *state,
@@ -1890,7 +1890,7 @@ bt_downlink_missing_check(BtreeCheckState *state)
  * also allows us to detect the corruption in many cases.
  */
 static void
-bt_tuple_present_callback(Relation index, HeapTuple htup, Datum *values,
+bt_tuple_present_callback(Relation index, ItemPointer tid, Datum *values,
 						  bool *isnull, bool tupleIsAlive, void *checkstate)
 {
 	BtreeCheckState *state = (BtreeCheckState *) checkstate;
@@ -1901,7 +1901,7 @@ bt_tuple_present_callback(Relation index, HeapTuple htup, Datum *values,
 
 	/* Generate a normalized index tuple for fingerprinting */
 	itup = index_form_tuple(RelationGetDescr(index), values, isnull);
-	itup->t_tid = htup->t_self;
+	itup->t_tid = *tid;
 	norm = bt_normalize_tuple(state, itup);
 
 	/* Probe Bloom filter -- tuple should be present */

contrib/bloom/blinsert.c

@@ -72,7 +72,7 @@ initCachedPage(BloomBuildState *buildstate)
  * Per-tuple callback for table_index_build_scan.
  */
 static void
-bloomBuildCallback(Relation index, HeapTuple htup, Datum *values,
+bloomBuildCallback(Relation index, ItemPointer tid, Datum *values,
 				   bool *isnull, bool tupleIsAlive, void *state)
 {
 	BloomBuildState *buildstate = (BloomBuildState *) state;
@@ -81,7 +81,7 @@ bloomBuildCallback(Relation index, HeapTuple htup, Datum *values,
 
 	oldCtx = MemoryContextSwitchTo(buildstate->tmpCtx);
 
-	itup = BloomFormTuple(&buildstate->blstate, &htup->t_self, values, isnull);
+	itup = BloomFormTuple(&buildstate->blstate, tid, values, isnull);
 
 	/* Try to add next item to cached page */
 	if (BloomPageAddItem(&buildstate->blstate, buildstate->data.data, itup))

src/backend/access/brin/brin.c

@@ -597,7 +597,7 @@ brinendscan(IndexScanDesc scan)
  */
 static void
 brinbuildCallback(Relation index,
-				  HeapTuple htup,
+				  ItemPointer tid,
 				  Datum *values,
 				  bool *isnull,
 				  bool tupleIsAlive,
@@ -607,7 +607,7 @@ brinbuildCallback(Relation index,
 	BlockNumber thisblock;
 	int			i;
 
-	thisblock = ItemPointerGetBlockNumber(&htup->t_self);
+	thisblock = ItemPointerGetBlockNumber(tid);
 
 	/*
 	 * If we're in a block that belongs to a future range, summarize what

src/backend/access/gin/gininsert.c

@@ -276,7 +276,7 @@ ginHeapTupleBulkInsert(GinBuildState *buildstate, OffsetNumber attnum,
 }
 
 static void
-ginBuildCallback(Relation index, HeapTuple htup, Datum *values,
+ginBuildCallback(Relation index, ItemPointer tid, Datum *values,
 				 bool *isnull, bool tupleIsAlive, void *state)
 {
 	GinBuildState *buildstate = (GinBuildState *) state;
@@ -287,8 +287,7 @@ ginBuildCallback(Relation index, HeapTuple htup, Datum *values,
 
 	for (i = 0; i < buildstate->ginstate.origTupdesc->natts; i++)
 		ginHeapTupleBulkInsert(buildstate, (OffsetNumber) (i + 1),
-							   values[i], isnull[i],
-							   &htup->t_self);
+							   values[i], isnull[i], tid);
 
 	/* If we've maxed out our available memory, dump everything to the index */
 	if (buildstate->accum.allocatedMemory >= (Size) maintenance_work_mem * 1024L)

src/backend/access/gist/gistbuild.c

@@ -80,7 +80,7 @@ typedef struct
 static void gistInitBuffering(GISTBuildState *buildstate);
 static int	calculatePagesPerBuffer(GISTBuildState *buildstate, int levelStep);
 static void gistBuildCallback(Relation index,
-							  HeapTuple htup,
+							  ItemPointer tid,
 							  Datum *values,
 							  bool *isnull,
 							  bool tupleIsAlive,
@@ -440,7 +440,7 @@ calculatePagesPerBuffer(GISTBuildState *buildstate, int levelStep)
  */
 static void
 gistBuildCallback(Relation index,
-				  HeapTuple htup,
+				  ItemPointer tid,
 				  Datum *values,
 				  bool *isnull,
 				  bool tupleIsAlive,
@@ -454,7 +454,7 @@ gistBuildCallback(Relation index,
 
 	/* form an index tuple and point it at the heap tuple */
 	itup = gistFormTuple(buildstate->giststate, index, values, isnull, true);
-	itup->t_tid = htup->t_self;
+	itup->t_tid = *tid;
 
 	if (buildstate->bufferingMode == GIST_BUFFERING_ACTIVE)
 	{

src/backend/access/hash/hash.c

@@ -43,7 +43,7 @@ typedef struct
 } HashBuildState;
 
 static void hashbuildCallback(Relation index,
-							  HeapTuple htup,
+							  ItemPointer tid,
 							  Datum *values,
 							  bool *isnull,
 							  bool tupleIsAlive,
@@ -201,7 +201,7 @@ hashbuildempty(Relation index)
  */
 static void
 hashbuildCallback(Relation index,
-				  HeapTuple htup,
+				  ItemPointer tid,
 				  Datum *values,
 				  bool *isnull,
 				  bool tupleIsAlive,
@@ -220,14 +220,13 @@ hashbuildCallback(Relation index,
 
 	/* Either spool the tuple for sorting, or just put it into the index */
 	if (buildstate->spool)
-		_h_spool(buildstate->spool, &htup->t_self,
-				 index_values, index_isnull);
+		_h_spool(buildstate->spool, tid, index_values, index_isnull);
 	else
 	{
 		/* form an index tuple and point it at the heap tuple */
 		itup = index_form_tuple(RelationGetDescr(index),
 								index_values, index_isnull);
-		itup->t_tid = htup->t_self;
+		itup->t_tid = *tid;
 		_hash_doinsert(index, itup, buildstate->heapRel);
 		pfree(itup);
 	}

src/backend/access/heap/heapam_handler.c

@@ -1636,10 +1636,9 @@ heapam_index_build_range_scan(Relation heapRelation,
 			 * For a heap-only tuple, pretend its TID is that of the root. See
 			 * src/backend/access/heap/README.HOT for discussion.
 			 */
-			HeapTupleData rootTuple;
+			ItemPointerData tid;
 			OffsetNumber offnum;
 
-			rootTuple = *heapTuple;
 			offnum = ItemPointerGetOffsetNumber(&heapTuple->t_self);
 
 			if (!OffsetNumberIsValid(root_offsets[offnum - 1]))
@@ -1650,18 +1649,18 @@ heapam_index_build_range_scan(Relation heapRelation,
 										 offnum,
 										 RelationGetRelationName(heapRelation))));
 
-			ItemPointerSetOffsetNumber(&rootTuple.t_self,
-									   root_offsets[offnum - 1]);
+			ItemPointerSet(&tid, ItemPointerGetBlockNumber(&heapTuple->t_self),
+						   root_offsets[offnum - 1]);
 
 			/* Call the AM's callback routine to process the tuple */
-			callback(indexRelation, &rootTuple, values, isnull, tupleIsAlive,
+			callback(indexRelation, &tid, values, isnull, tupleIsAlive,
 					 callback_state);
 		}
 		else
 		{
 			/* Call the AM's callback routine to process the tuple */
-			callback(indexRelation, heapTuple, values, isnull, tupleIsAlive,
-					 callback_state);
+			callback(indexRelation, &heapTuple->t_self, values, isnull,
+					 tupleIsAlive, callback_state);
 		}
 	}
 

src/backend/access/nbtree/nbtsort.c

@@ -269,7 +269,7 @@ static void _bt_spooldestroy(BTSpool *btspool);
 static void _bt_spool(BTSpool *btspool, ItemPointer self,
 					  Datum *values, bool *isnull);
 static void _bt_leafbuild(BTSpool *btspool, BTSpool *btspool2);
-static void _bt_build_callback(Relation index, HeapTuple htup, Datum *values,
+static void _bt_build_callback(Relation index, ItemPointer tid, Datum *values,
 							   bool *isnull, bool tupleIsAlive, void *state);
 static Page _bt_blnewpage(uint32 level);
 static BTPageState *_bt_pagestate(BTWriteState *wstate, uint32 level);
@@ -585,7 +585,7 @@ _bt_leafbuild(BTSpool *btspool, BTSpool *btspool2)
  */
 static void
 _bt_build_callback(Relation index,
-				   HeapTuple htup,
+				   ItemPointer tid,
 				   Datum *values,
 				   bool *isnull,
 				   bool tupleIsAlive,
@@ -598,12 +598,12 @@ _bt_build_callback(Relation index,
 	 * processing
 	 */
 	if (tupleIsAlive || buildstate->spool2 == NULL)
-		_bt_spool(buildstate->spool, &htup->t_self, values, isnull);
+		_bt_spool(buildstate->spool, tid, values, isnull);
 	else
 	{
 		/* dead tuples are put into spool2 */
 		buildstate->havedead = true;
-		_bt_spool(buildstate->spool2, &htup->t_self, values, isnull);
+		_bt_spool(buildstate->spool2, tid, values, isnull);
 	}
 
 	buildstate->indtuples += 1;

src/backend/access/spgist/spginsert.c

@@ -40,7 +40,7 @@ typedef struct
 
 /* Callback to process one heap tuple during table_index_build_scan */
 static void
-spgistBuildCallback(Relation index, HeapTuple htup, Datum *values,
+spgistBuildCallback(Relation index, ItemPointer tid, Datum *values,
 					bool *isnull, bool tupleIsAlive, void *state)
 {
 	SpGistBuildState *buildstate = (SpGistBuildState *) state;
@@ -55,7 +55,7 @@ spgistBuildCallback(Relation index, HeapTuple htup, Datum *values,
 	 * lock on some buffer.  So we need to be willing to retry.  We can flush
 	 * any temp data when retrying.
 	 */
-	while (!spgdoinsert(index, &buildstate->spgstate, &htup->t_self,
+	while (!spgdoinsert(index, &buildstate->spgstate, tid,
 						*values, *isnull))
 	{
 		MemoryContextReset(buildstate->tmpCtx);

src/include/access/tableam.h

@@ -141,7 +141,7 @@ typedef struct TM_FailureData
 
 /* Typedef for callback function for table_index_build_scan */
 typedef void (*IndexBuildCallback) (Relation index,
-									HeapTuple htup,
+									ItemPointer tid,
 									Datum *values,
 									bool *isnull,
 									bool tupleIsAlive,