Subject: [PATCH v34 2/5] Subscripting for array

From: erthalion <[email-masked]>
Date: Fri, 1 Feb 2019 11:38:52 +0100

Subscripting implementation for array data types. It includes all array
specific parts, that were removed from the generalized code. Note, that
for some array-like data types it's not necessary to assign
array_subscript_handler explicitely, since it's done in Catalog.pm

Reviewed-by: Tom Lane, Arthur Zakirov
---
 src/backend/catalog/Catalog.pm        |   1 +
 src/backend/catalog/heap.c            |   2 +-
 src/backend/commands/typecmds.c       |   8 +-
 src/backend/executor/execExprInterp.c |  15 +-
 src/backend/nodes/nodeFuncs.c         |   2 +-
 src/backend/parser/parse_node.c       |  11 -
 src/backend/parser/parse_target.c     |   4 +-
 src/backend/utils/adt/arrayfuncs.c    | 289 ++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat       |   7 +
 src/include/catalog/pg_type.dat       |  30 ++-
 src/test/regress/expected/arrays.out  |  12 +-
 src/test/regress/sql/arrays.sql       |   4 +-
 12 files changed, 346 insertions(+), 39 deletions(-)

diff --git a/src/backend/catalog/Catalog.pm b/src/backend/catalog/Catalog.pm
index dd39a086ce..b4dfa26518 100644
--- a/src/backend/catalog/Catalog.pm
+++ b/src/backend/catalog/Catalog.pm
@@ -384,6 +384,7 @@ sub GenerateArrayTypes
 		# Arrays require INT alignment, unless the element type requires
 		# DOUBLE alignment.
 		$array_type{typalign} = $elem_type->{typalign} eq 'd' ? 'd' : 'i';
+		$array_type{typsubshandler} = 'array_subscript_handler';
 
 		# Fill in the rest of the array entry's fields.
 		foreach my $column (@$pgtype_schema)
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 4d552589ae..4703d8076b 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -1372,7 +1372,7 @@ heap_create_with_catalog(const char *relname,
 				   0,			/* array dimensions for typBaseType */
 				   false,		/* Type NOT NULL */
 				   InvalidOid,  /* rowtypes never have a collation */
-				   0);	/* array implementation */
+				   F_ARRAY_SUBSCRIPT_HANDLER);	/* array implementation */
 
 		pfree(relarrayname);
 	}
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 33d4fb401d..596c6cf3ca 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -618,7 +618,7 @@ DefineType(ParseState *pstate, List *names, List *parameters)
 			   0,				/* Array dimensions of typbasetype */
 			   false,			/* Type NOT NULL */
 			   collation,		/* type's collation */
-			   0);
+			   F_ARRAY_SUBSCRIPT_HANDLER);
 
 	pfree(array_type);
 
@@ -1065,7 +1065,7 @@ DefineDomain(CreateDomainStmt *stmt)
 			   0,				/* Array dimensions of typbasetype */
 			   false,			/* Type NOT NULL */
 			   domaincoll,		/* type's collation */
-			   0); /* array subscripting implementation */
+			   F_ARRAY_SUBSCRIPT_HANDLER); /* array subscripting implementation */
 
 	pfree(domainArrayName);
 
@@ -1222,7 +1222,7 @@ DefineEnum(CreateEnumStmt *stmt)
 			   0,				/* Array dimensions of typbasetype */
 			   false,			/* Type NOT NULL */
 			   InvalidOid,		/* type's collation */
-			   0);	/* array subscripting implementation */
+			   F_ARRAY_SUBSCRIPT_HANDLER);	/* array subscripting implementation */
 
 	pfree(enumArrayName);
 
@@ -1555,7 +1555,7 @@ DefineRange(CreateRangeStmt *stmt)
 			   0,				/* Array dimensions of typbasetype */
 			   false,			/* Type NOT NULL */
 			   InvalidOid,		/* typcollation */
-			   0);	/* array subscripting implementation */
+			   F_ARRAY_SUBSCRIPT_HANDLER);	/* array subscripting implementation */
 
 	pfree(rangeArrayName);
 
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 838bb4d005..b87daf65e0 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -3155,7 +3155,7 @@ ExecEvalSubscriptingRef(ExprState *state, ExprEvalStep *op)
 		if (sbsrefstate->isassignment)
 			ereport(ERROR,
 					(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
-					 errmsg("array subscript in assignment must not be null")));
+					 errmsg("subscript in assignment must not be null")));
 		*op->resnull = true;
 		return false;
 	}
@@ -3227,9 +3227,20 @@ ExecEvalSubscriptingRefOld(ExprState *state, ExprEvalStep *op)
 void
 ExecEvalSubscriptingRefAssign(ExprState *state, ExprEvalStep *op)
 {
-	SubscriptingRefState *sbsrefstate = op->d.sbsref_subscript.state;
+	SubscriptingRefState *sbsrefstate = op->d.sbsref.state;
 	SubscriptRoutines	 *sbsroutines = sbsrefstate->sbsroutines;
 
+	/*
+	 * For an assignment to a fixed-length container type, both the original
+	 * container and the value to be assigned into it must be non-NULL, else we
+	 * punt and return the original container.
+	 */
+	if (sbsrefstate->refattrlength > 0)
+	{
+		if (*op->resnull || sbsrefstate->replacenull)
+			return;
+	}
+
 	sbsrefstate->resnull = *op->resnull;
 	*op->resvalue = sbsroutines->assign(*op->resvalue, sbsrefstate);
 	*op->resnull = sbsrefstate->resnull;
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 9ce8f43385..0fd9d8b110 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -70,7 +70,7 @@ exprType(const Node *expr)
 				const SubscriptingRef *sbsref = (const SubscriptingRef *) expr;
 
 				/* slice and/or store operations yield the container type */
-				if (sbsref->reflowerindexpr || sbsref->refassgnexpr)
+				if (IsAssignment(sbsref) || sbsref->reflowerindexpr)
 					type = sbsref->refcontainertype;
 				else
 					type = sbsref->refelemtype;
diff --git a/src/backend/parser/parse_node.c b/src/backend/parser/parse_node.c
index 4f46d6310a..d1c4ea8573 100644
--- a/src/backend/parser/parse_node.c
+++ b/src/backend/parser/parse_node.c
@@ -309,17 +309,6 @@ transformContainerSubscripts(ParseState *pstate,
 			lowerIndexpr = lappend(lowerIndexpr, subexpr);
 			indexprSlice = lappend(indexprSlice, ai);
 		}
-		else
-			Assert(ai->lidx == NULL && !ai->is_slice);
-
-		if (ai->uidx)
-			subexpr = transformExpr(pstate, ai->uidx, pstate->p_expr_kind);
-		else
-		{
-			/* Slice with omitted upper bound, put NULL into the list */
-			Assert(isSlice && ai->is_slice);
-			subexpr = NULL;
-		}
 		subexpr = transformExpr(pstate, ai->uidx, pstate->p_expr_kind);
 		upperIndexpr = lappend(upperIndexpr, subexpr);
 	}
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index d7483c6538..0161d0f540 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -685,7 +685,7 @@ transformAssignmentIndirection(ParseState *pstate,
 							   Node *rhs,
 							   int location)
 {
-	Node	   *result = NULL;
+	Node	   *result;
 	List	   *subscripts = NIL;
 	bool		isSlice = false;
 	ListCell   *i;
@@ -873,6 +873,8 @@ transformAssignmentIndirection(ParseState *pstate,
 					 errhint("You will need to rewrite or cast the expression."),
 					 parser_errposition(pstate, location)));
 	}
+	else
+		result = rhs;
 
 	return result;
 }
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index 392445ea03..21bd5882b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -25,14 +25,20 @@
 #include "nodes/supportnodes.h"
 #include "optimizer/optimizer.h"
 #include "port/pg_bitutils.h"
+#include "nodes/makefuncs.h"
+#include "executor/execExpr.h"
 #include "utils/array.h"
 #include "utils/arrayaccess.h"
 #include "utils/builtins.h"
 #include "utils/datum.h"
+#include "utils/fmgroids.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
 #include "utils/selfuncs.h"
+#include "utils/syscache.h"
 #include "utils/typcache.h"
+#include "parser/parse_node.h"
+#include "parser/parse_coerce.h"

 /*
@@ -159,7 +165,14 @@ static int	width_bucket_array_variable(Datum operand,
 										ArrayType *thresholds,
 										Oid collation,
 										TypeCacheEntry *typentry);
+static SubscriptingRef *array_subscript_prepare(bool isAssignment, SubscriptingRef *sbsref);
+static SubscriptingRef *array_subscript_validate(bool isAssignment, SubscriptingRef *sbsref,
+												 ParseState *pstate);
 
+static Datum array_subscript_fetch(Datum containerSource,
+								   SubscriptingRefState *sbstate);
+static Datum array_subscript_assign(Datum containerSource,
+									SubscriptingRefState *sbstate);
 
 /*
  * array_in :
@@ -6626,3 +6639,279 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Perform an actual data extraction or modification for the array
+ * subscripting. As a result the extracted Datum or the modified containers
+ * value will be returned.
+ */
+Datum
+array_subscript_assign(Datum containerSource, SubscriptingRefState *sbstate)
+{
+	bool						is_slice = (sbstate->numlower != 0);
+	IntArray					u_index, l_index;
+	bool						eisnull = sbstate->resnull;
+	int							i = 0;
+
+	if (sbstate->refelemlength == 0)
+	{
+		/* do one-time catalog lookups for type info */
+		get_typlenbyvalalign(sbstate->refelemtype,
+							 &sbstate->refelemlength,
+							 &sbstate->refelembyval,
+							 &sbstate->refelemalign);
+	}
+
+	for(i = 0; i < sbstate->numupper; i++)
+		u_index.indx[i] = DatumGetInt32(sbstate->upperindex[i]);
+
+	if (is_slice)
+	{
+		for(i = 0; i < sbstate->numlower; i++)
+			l_index.indx[i] = DatumGetInt32(sbstate->lowerindex[i]);
+	}
+
+	/*
+	 * For assignment to varlena arrays, we handle a NULL original array
+	 * by substituting an empty (zero-dimensional) array; insertion of the
+	 * new element will result in a singleton array value.  It does not
+	 * matter whether the new element is NULL.
+	 */
+	if (eisnull)
+	{
+		containerSource = PointerGetDatum(construct_empty_array(sbstate->refelemtype));
+		sbstate->resnull = false;
+		eisnull = false;
+	}
+
+	if (!is_slice)
+		return array_set_element(containerSource, sbstate->numupper,
+								 u_index.indx,
+								 sbstate->replacevalue,
+								 sbstate->replacenull,
+								 sbstate->refattrlength,
+								 sbstate->refelemlength,
+								 sbstate->refelembyval,
+								 sbstate->refelemalign);
+	else
+		return array_set_slice(containerSource, sbstate->numupper,
+							   u_index.indx, l_index.indx,
+							   sbstate->upperprovided,
+							   sbstate->lowerprovided,
+							   sbstate->replacevalue,
+							   sbstate->replacenull,
+							   sbstate->refattrlength,
+							   sbstate->refelemlength,
+							   sbstate->refelembyval,
+							   sbstate->refelemalign);
+}
+
+Datum
+array_subscript_fetch(Datum containerSource, SubscriptingRefState *sbstate)
+{
+	bool							is_slice = (sbstate->numlower != 0);
+	IntArray						u_index, l_index;
+	int								i = 0;
+
+	if (sbstate->refelemlength == 0)
+	{
+		/* do one-time catalog lookups for type info */
+		get_typlenbyvalalign(sbstate->refelemtype,
+							 &sbstate->refelemlength,
+							 &sbstate->refelembyval,
+							 &sbstate->refelemalign);
+	}
+
+	for(i = 0; i < sbstate->numupper; i++)
+		u_index.indx[i] = DatumGetInt32(sbstate->upperindex[i]);
+
+	if (is_slice)
+	{
+		for(i = 0; i < sbstate->numlower; i++)
+			l_index.indx[i] = DatumGetInt32(sbstate->lowerindex[i]);
+	}
+
+	if (!is_slice)
+		return array_get_element(containerSource, sbstate->numupper,
+								 u_index.indx,
+								 sbstate->refattrlength,
+								 sbstate->refelemlength,
+								 sbstate->refelembyval,
+								 sbstate->refelemalign,
+								 &sbstate->resnull);
+	else
+		return array_get_slice(containerSource, sbstate->numupper,
+							   u_index.indx, l_index.indx,
+							   sbstate->upperprovided,
+							   sbstate->lowerprovided,
+							   sbstate->refattrlength,
+							   sbstate->refelemlength,
+							   sbstate->refelembyval,
+							   sbstate->refelemalign);
+}
+
+/*
+ * Handle array-type subscripting logic.
+ */
+Datum
+array_subscript_handler(PG_FUNCTION_ARGS)
+{
+	SubscriptRoutines *sbsroutines = (SubscriptRoutines *)
+									 palloc(sizeof(SubscriptRoutines));
+
+	sbsroutines->prepare = array_subscript_prepare;
+	sbsroutines->validate = array_subscript_validate;
+	sbsroutines->fetch = array_subscript_fetch;
+	sbsroutines->assign = array_subscript_assign;
+
+	PG_RETURN_POINTER(sbsroutines);
+}
+
+SubscriptingRef *
+array_subscript_prepare(bool isAssignment, SubscriptingRef *sbsref)
+{
+	Oid					array_type = sbsref->refcontainertype;
+	HeapTuple			type_tuple_container;
+	Form_pg_type		type_struct_container;
+	bool				is_slice = sbsref->reflowerindexpr != NIL;
+
+	/* Get the type tuple for the container */
+	type_tuple_container = SearchSysCache1(TYPEOID, ObjectIdGetDatum(array_type));
+	if (!HeapTupleIsValid(type_tuple_container))
+		elog(ERROR, "cache lookup failed for type %u", array_type);
+	type_struct_container = (Form_pg_type) GETSTRUCT(type_tuple_container);
+
+	/* needn't check typisdefined since this will fail anyway */
+	sbsref->refelemtype = type_struct_container->typelem;
+
+	/* Identify type that RHS must provide */
+	if (isAssignment)
+		sbsref->refassgntype = is_slice ? sbsref->refcontainertype : sbsref->refelemtype;
+
+	ReleaseSysCache(type_tuple_container);
+
+	return sbsref;
+}
+
+SubscriptingRef *
+array_subscript_validate(bool isAssignment, SubscriptingRef *sbsref,
+					  ParseState *pstate)
+{
+	bool				is_slice = sbsref->reflowerindexpr != NIL;
+	Oid					typeneeded = InvalidOid,
+						typesource = InvalidOid;
+	Node				*new_from;
+	Node				*subexpr;
+	List				*upperIndexpr = NIL;
+	List				*lowerIndexpr = NIL;
+	ListCell			*u, *l, *s;
+
+	foreach(u, sbsref->refupperindexpr)
+	{
+		subexpr = (Node *) lfirst(u);
+
+		if (subexpr == NULL)
+		{
+			upperIndexpr = lappend(upperIndexpr, subexpr);
+			continue;
+		}
+
+		subexpr = coerce_to_target_type(pstate,
+										subexpr, exprType(subexpr),
+										INT4OID, -1,
+										COERCION_ASSIGNMENT,
+										COERCE_IMPLICIT_CAST,
+										-1);
+		if (subexpr == NULL)
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("array subscript must have type integer"),
+					 parser_errposition(pstate, exprLocation(subexpr))));
+
+		upperIndexpr = lappend(upperIndexpr, subexpr);
+	}
+
+	sbsref->refupperindexpr = upperIndexpr;
+
+	forboth(l, sbsref->reflowerindexpr, s, sbsref->refindexprslice)
+	{
+		A_Indices *ai = (A_Indices *) lfirst(s);
+		subexpr = (Node *) lfirst(l);
+
+		if (subexpr == NULL && !ai->is_slice)
+		{
+			/* Make a constant 1 */
+			subexpr = (Node *) makeConst(INT4OID,
+										 -1,
+										 InvalidOid,
+										 sizeof(int32),
+										 Int32GetDatum(1),
+										 false,
+										 true);		/* pass by value */
+		}
+
+		if (subexpr == NULL)
+		{
+			lowerIndexpr = lappend(lowerIndexpr, subexpr);
+			continue;
+		}
+
+		subexpr = coerce_to_target_type(pstate,
+										subexpr, exprType(subexpr),
+										INT4OID, -1,
+										COERCION_ASSIGNMENT,
+										COERCE_IMPLICIT_CAST,
+										-1);
+		if (subexpr == NULL)
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("array subscript must have type integer"),
+					 parser_errposition(pstate, exprLocation(subexpr))));
+
+		lowerIndexpr = lappend(lowerIndexpr, subexpr);
+	}
+
+	sbsref->reflowerindexpr = lowerIndexpr;
+
+	if (isAssignment)
+	{
+		SubscriptingRef *assignRef = (SubscriptingRef *) sbsref;
+		Node *assignExpr = (Node *) assignRef->refassgnexpr;
+
+		typesource = exprType(assignExpr);
+		typeneeded = is_slice ? sbsref->refcontainertype : sbsref->refelemtype;
+		new_from = coerce_to_target_type(pstate,
+										assignExpr, typesource,
+										typeneeded, sbsref->reftypmod,
+										COERCION_ASSIGNMENT,
+										COERCE_IMPLICIT_CAST,
+										-1);
+		if (new_from == NULL)
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("array assignment requires type %s"
+							" but expression is of type %s",
+							format_type_be(sbsref->refelemtype),
+							format_type_be(typesource)),
+				 errhint("You will need to rewrite or cast the expression."),
+					 parser_errposition(pstate, exprLocation(assignExpr))));
+		assignRef->refassgnexpr = (Expr *) new_from;
+	}
+
+	sbsref->refnestedfunc = F_ARRAY_SUBSCRIPT_HANDLER;
+
+	/* Verify subscript list lengths are within limit */
+	if (list_length(sbsref->refupperindexpr) > MAXDIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+				 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
+						list_length(sbsref->refupperindexpr), MAXDIM)));
+
+	if (list_length(sbsref->reflowerindexpr) > MAXDIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+				 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
+						list_length(sbsref->reflowerindexpr), MAXDIM)));
+
+	return sbsref;
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index f48f5fb4d9..2c6aa65bf8 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -10898,6 +10898,13 @@
   proargnames => '{max_data_alignment,database_block_size,blocks_per_segment,wal_block_size,bytes_per_wal_segment,max_identifier_length,max_index_columns,max_toast_chunk_size,large_object_chunk_size,float8_pass_by_value,data_page_checksum_version}',
   prosrc => 'pg_control_init' },
 
+{ oid => '6099',
+  descr => 'Array subscripting logic',
+  proname => 'array_subscript_handler',
+  prorettype => 'internal',
+  proargtypes => 'internal',
+  prosrc => 'array_subscript_handler' },
+
 # collation management functions
 { oid => '3445', descr => 'import collations from operating system',
   proname => 'pg_import_system_collations', procost => '100',
diff --git a/src/include/catalog/pg_type.dat b/src/include/catalog/pg_type.dat
index b2cec07416..21489a02ae 100644
--- a/src/include/catalog/pg_type.dat
+++ b/src/include/catalog/pg_type.dat
@@ -54,7 +54,8 @@
   typname => 'name', typlen => 'NAMEDATALEN', typbyval => 'f',
   typcategory => 'S', typelem => 'char', typinput => 'namein',
   typoutput => 'nameout', typreceive => 'namerecv', typsend => 'namesend',
-  typalign => 'c', typcollation => 'C' },
+  typalign => 'c', typcollation => 'C',
+  typsubshandler => 'array_subscript_handler' },
 { oid => '20', array_type_oid => '1016',
   descr => '~18 digit integer, 8-byte storage',
   typname => 'int8', typlen => '8', typbyval => 'FLOAT8PASSBYVAL',
@@ -70,7 +71,7 @@
   typname => 'int2vector', typlen => '-1', typbyval => 'f', typcategory => 'A',
   typelem => 'int2', typinput => 'int2vectorin', typoutput => 'int2vectorout',
   typreceive => 'int2vectorrecv', typsend => 'int2vectorsend',
-  typalign => 'i' },
+  typalign => 'i', typsubshandler => 'array_subscript_handler' },
 { oid => '23', array_type_oid => '1007',
   descr => '-2 billion to 2 billion integer, 4-byte storage',
   typname => 'int4', typlen => '4', typbyval => 't', typcategory => 'N',
@@ -109,7 +110,8 @@
   descr => 'array of oids, used in system tables',
   typname => 'oidvector', typlen => '-1', typbyval => 'f', typcategory => 'A',
   typelem => 'oid', typinput => 'oidvectorin', typoutput => 'oidvectorout',
-  typreceive => 'oidvectorrecv', typsend => 'oidvectorsend', typalign => 'i' },
+  typreceive => 'oidvectorrecv', typsend => 'oidvectorsend', typalign => 'i',
+  typsubshandler => 'array_subscript_handler' },
 
 # hand-built rowtype entries for bootstrapped catalogs
 # NB: OIDs assigned here must match the BKI_ROWTYPE_OID declarations
@@ -188,32 +190,37 @@
   descr => 'geometric point \'(x, y)\'',
   typname => 'point', typlen => '16', typbyval => 'f', typcategory => 'G',
   typelem => 'float8', typinput => 'point_in', typoutput => 'point_out',
-  typreceive => 'point_recv', typsend => 'point_send', typalign => 'd' },
+  typreceive => 'point_recv', typsend => 'point_send', typalign => 'd',
+  typsubshandler => 'array_subscript_handler' },
 { oid => '601', array_type_oid => '1018',
   descr => 'geometric line segment \'(pt1,pt2)\'',
   typname => 'lseg', typlen => '32', typbyval => 'f', typcategory => 'G',
   typelem => 'point', typinput => 'lseg_in', typoutput => 'lseg_out',
-  typreceive => 'lseg_recv', typsend => 'lseg_send', typalign => 'd' },
+  typreceive => 'lseg_recv', typsend => 'lseg_send', typalign => 'd',
+  typsubshandler => 'array_subscript_handler' },
 { oid => '602', array_type_oid => '1019',
   descr => 'geometric path \'(pt1,...)\'',
   typname => 'path', typlen => '-1', typbyval => 'f', typcategory => 'G',
   typinput => 'path_in', typoutput => 'path_out', typreceive => 'path_recv',
-  typsend => 'path_send', typalign => 'd', typstorage => 'x' },
+  typsend => 'path_send', typalign => 'd', typstorage => 'x',
+  typsubshandler => 'array_subscript_handler' },
 { oid => '603', array_type_oid => '1020',
   descr => 'geometric box \'(lower left,upper right)\'',
   typname => 'box', typlen => '32', typbyval => 'f', typcategory => 'G',
   typdelim => ';', typelem => 'point', typinput => 'box_in',
   typoutput => 'box_out', typreceive => 'box_recv', typsend => 'box_send',
-  typalign => 'd' },
+  typalign => 'd', typsubshandler => 'array_subscript_handler' },
 { oid => '604', array_type_oid => '1027',
   descr => 'geometric polygon \'(pt1,...)\'',
   typname => 'polygon', typlen => '-1', typbyval => 'f', typcategory => 'G',
   typinput => 'poly_in', typoutput => 'poly_out', typreceive => 'poly_recv',
-  typsend => 'poly_send', typalign => 'd', typstorage => 'x' },
+  typsend => 'poly_send', typalign => 'd', typstorage => 'x',
+  typsubshandler => 'array_subscript_handler' },
 { oid => '628', array_type_oid => '629', descr => 'geometric line',
   typname => 'line', typlen => '24', typbyval => 'f', typcategory => 'G',
   typelem => 'float8', typinput => 'line_in', typoutput => 'line_out',
-  typreceive => 'line_recv', typsend => 'line_send', typalign => 'd' },
+  typreceive => 'line_recv', typsend => 'line_send', typalign => 'd',
+  typsubshandler => 'array_subscript_handler' },
 
 # OIDS 700 - 799
 
@@ -272,7 +279,7 @@
 { oid => '1033', array_type_oid => '1034', descr => 'access control list',
   typname => 'aclitem', typlen => '12', typbyval => 'f', typcategory => 'U',
   typinput => 'aclitemin', typoutput => 'aclitemout', typreceive => '-',
-  typsend => '-', typalign => 'i' },
+  typsend => '-', typalign => 'i', typsubshandler => 'array_subscript_handler' },
 { oid => '1042', array_type_oid => '1014',
   descr => 'char(length), blank-padded string, fixed storage length',
   typname => 'bpchar', typlen => '-1', typbyval => 'f', typcategory => 'S',
@@ -311,7 +318,8 @@
   typcategory => 'D', typispreferred => 't', typinput => 'timestamptz_in',
   typoutput => 'timestamptz_out', typreceive => 'timestamptz_recv',
   typsend => 'timestamptz_send', typmodin => 'timestamptztypmodin',
-  typmodout => 'timestamptztypmodout', typalign => 'd' },
+  typmodout => 'timestamptztypmodout', typalign => 'd',
+  typsubshandler => 'array_subscript_handler' },
 { oid => '1186', array_type_oid => '1187',
   descr => '@ <number> <units>, time interval',
   typname => 'interval', typlen => '16', typbyval => 'f', typcategory => 'T',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index f9d9ad6aef..46b8cd4b98 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -190,9 +190,9 @@ select ('[0:2][0:2]={{1,2,3},{4,5,6},{7,8,9}}'::int[])[1:2][2];
 --
 -- check subscription corner cases
 --
--- More subscripts than MAXDIMS(6)
-SELECT ('{}'::int[])[1][2][3][4][5][6][7];
-ERROR:  number of array dimensions (7) exceeds the maximum allowed (6)
+-- More subscripts than MAXDIMS(12)
+SELECT ('{}'::int[])[1][2][3][4][5][6][7][8][9][10][11][12][13];
+ERROR:  number of array dimensions (13) exceeds the maximum allowed (6)
 -- NULL index yields NULL when selecting
 SELECT ('{{{1},{2},{3}},{{4},{5},{6}}}'::int[])[1][NULL][1];
  int4 
@@ -216,15 +216,15 @@ SELECT ('{{{1},{2},{3}},{{4},{5},{6}}}'::int[])[1][1:NULL][1];
 UPDATE arrtest
   SET c[NULL] = '{"can''t assign"}'
   WHERE array_dims(c) is not null;
-ERROR:  array subscript in assignment must not be null
+ERROR:  subscript in assignment must not be null
 UPDATE arrtest
   SET c[NULL:1] = '{"can''t assign"}'
   WHERE array_dims(c) is not null;
-ERROR:  array subscript in assignment must not be null
+ERROR:  subscript in assignment must not be null
 UPDATE arrtest
   SET c[1:NULL] = '{"can''t assign"}'
   WHERE array_dims(c) is not null;
-ERROR:  array subscript in assignment must not be null
+ERROR:  subscript in assignment must not be null
 -- test slices with empty lower and/or upper index
 CREATE TEMP TABLE arrtest_s (
   a       int2[],
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index 2b689ae88f..afccaf25e1 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -106,8 +106,8 @@ select ('[0:2][0:2]={{1,2,3},{4,5,6},{7,8,9}}'::int[])[1:2][2];
 --
 -- check subscription corner cases
 --
--- More subscripts than MAXDIMS(6)
-SELECT ('{}'::int[])[1][2][3][4][5][6][7];
+-- More subscripts than MAXDIMS(12)
+SELECT ('{}'::int[])[1][2][3][4][5][6][7][8][9][10][11][12][13];
 -- NULL index yields NULL when selecting
 SELECT ('{{{1},{2},{3}},{{4},{5},{6}}}'::int[])[1][NULL][1];
 SELECT ('{{{1},{2},{3}},{{4},{5},{6}}}'::int[])[1][NULL:1][1];
-- 
2.21.0

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