Adding upstream version 14.5.upstream/14.5upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 6722 insertions, 0 deletions

diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
new file mode 100644
index 0000000..55ba9f7
--- /dev/null
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -0,0 +1,6722 @@
+/*-------------------------------------------------------------------------
+ *
+ * arrayfuncs.c
+ *	  Support functions for arrays.
+ *
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/utils/adt/arrayfuncs.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include <ctype.h>
+#include <math.h>
+
+#include "access/htup_details.h"
+#include "catalog/pg_type.h"
+#include "funcapi.h"
+#include "libpq/pqformat.h"
+#include "nodes/nodeFuncs.h"
+#include "nodes/supportnodes.h"
+#include "optimizer/optimizer.h"
+#include "port/pg_bitutils.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/typcache.h"
+
+
+/*
+ * GUC parameter
+ */
+bool		Array_nulls = true;
+
+/*
+ * Local definitions
+ */
+#define ASSGN	 "="
+
+#define AARR_FREE_IF_COPY(array,n) \
+	do { \
+		if (!VARATT_IS_EXPANDED_HEADER(array)) \
+			PG_FREE_IF_COPY(array, n); \
+	} while (0)
+
+typedef enum
+{
+	ARRAY_NO_LEVEL,
+	ARRAY_LEVEL_STARTED,
+	ARRAY_ELEM_STARTED,
+	ARRAY_ELEM_COMPLETED,
+	ARRAY_QUOTED_ELEM_STARTED,
+	ARRAY_QUOTED_ELEM_COMPLETED,
+	ARRAY_ELEM_DELIMITED,
+	ARRAY_LEVEL_COMPLETED,
+	ARRAY_LEVEL_DELIMITED
+} ArrayParseState;
+
+/* Working state for array_iterate() */
+typedef struct ArrayIteratorData
+{
+	/* basic info about the array, set up during array_create_iterator() */
+	ArrayType  *arr;			/* array we're iterating through */
+	bits8	   *nullbitmap;		/* its null bitmap, if any */
+	int			nitems;			/* total number of elements in array */
+	int16		typlen;			/* element type's length */
+	bool		typbyval;		/* element type's byval property */
+	char		typalign;		/* element type's align property */
+
+	/* information about the requested slice size */
+	int			slice_ndim;		/* slice dimension, or 0 if not slicing */
+	int			slice_len;		/* number of elements per slice */
+	int		   *slice_dims;		/* slice dims array */
+	int		   *slice_lbound;	/* slice lbound array */
+	Datum	   *slice_values;	/* workspace of length slice_len */
+	bool	   *slice_nulls;	/* workspace of length slice_len */
+
+	/* current position information, updated on each iteration */
+	char	   *data_ptr;		/* our current position in the array */
+	int			current_item;	/* the item # we're at in the array */
+}			ArrayIteratorData;
+
+static bool array_isspace(char ch);
+static int	ArrayCount(const char *str, int *dim, char typdelim);
+static void ReadArrayStr(char *arrayStr, const char *origStr,
+						 int nitems, int ndim, int *dim,
+						 FmgrInfo *inputproc, Oid typioparam, int32 typmod,
+						 char typdelim,
+						 int typlen, bool typbyval, char typalign,
+						 Datum *values, bool *nulls,
+						 bool *hasnulls, int32 *nbytes);
+static void ReadArrayBinary(StringInfo buf, int nitems,
+							FmgrInfo *receiveproc, Oid typioparam, int32 typmod,
+							int typlen, bool typbyval, char typalign,
+							Datum *values, bool *nulls,
+							bool *hasnulls, int32 *nbytes);
+static Datum array_get_element_expanded(Datum arraydatum,
+										int nSubscripts, int *indx,
+										int arraytyplen,
+										int elmlen, bool elmbyval, char elmalign,
+										bool *isNull);
+static Datum array_set_element_expanded(Datum arraydatum,
+										int nSubscripts, int *indx,
+										Datum dataValue, bool isNull,
+										int arraytyplen,
+										int elmlen, bool elmbyval, char elmalign);
+static bool array_get_isnull(const bits8 *nullbitmap, int offset);
+static void array_set_isnull(bits8 *nullbitmap, int offset, bool isNull);
+static Datum ArrayCast(char *value, bool byval, int len);
+static int	ArrayCastAndSet(Datum src,
+							int typlen, bool typbyval, char typalign,
+							char *dest);
+static char *array_seek(char *ptr, int offset, bits8 *nullbitmap, int nitems,
+						int typlen, bool typbyval, char typalign);
+static int	array_nelems_size(char *ptr, int offset, bits8 *nullbitmap,
+							  int nitems, int typlen, bool typbyval, char typalign);
+static int	array_copy(char *destptr, int nitems,
+					   char *srcptr, int offset, bits8 *nullbitmap,
+					   int typlen, bool typbyval, char typalign);
+static int	array_slice_size(char *arraydataptr, bits8 *arraynullsptr,
+							 int ndim, int *dim, int *lb,
+							 int *st, int *endp,
+							 int typlen, bool typbyval, char typalign);
+static void array_extract_slice(ArrayType *newarray,
+								int ndim, int *dim, int *lb,
+								char *arraydataptr, bits8 *arraynullsptr,
+								int *st, int *endp,
+								int typlen, bool typbyval, char typalign);
+static void array_insert_slice(ArrayType *destArray, ArrayType *origArray,
+							   ArrayType *srcArray,
+							   int ndim, int *dim, int *lb,
+							   int *st, int *endp,
+							   int typlen, bool typbyval, char typalign);
+static int	array_cmp(FunctionCallInfo fcinfo);
+static ArrayType *create_array_envelope(int ndims, int *dimv, int *lbsv, int nbytes,
+										Oid elmtype, int dataoffset);
+static ArrayType *array_fill_internal(ArrayType *dims, ArrayType *lbs,
+									  Datum value, bool isnull, Oid elmtype,
+									  FunctionCallInfo fcinfo);
+static ArrayType *array_replace_internal(ArrayType *array,
+										 Datum search, bool search_isnull,
+										 Datum replace, bool replace_isnull,
+										 bool remove, Oid collation,
+										 FunctionCallInfo fcinfo);
+static int	width_bucket_array_float8(Datum operand, ArrayType *thresholds);
+static int	width_bucket_array_fixed(Datum operand,
+									 ArrayType *thresholds,
+									 Oid collation,
+									 TypeCacheEntry *typentry);
+static int	width_bucket_array_variable(Datum operand,
+										ArrayType *thresholds,
+										Oid collation,
+										TypeCacheEntry *typentry);
+
+
+/*
+ * array_in :
+ *		  converts an array from the external format in "string" to
+ *		  its internal format.
+ *
+ * return value :
+ *		  the internal representation of the input array
+ */
+Datum
+array_in(PG_FUNCTION_ARGS)
+{
+	char	   *string = PG_GETARG_CSTRING(0);	/* external form */
+	Oid			element_type = PG_GETARG_OID(1);	/* type of an array
+													 * element */
+	int32		typmod = PG_GETARG_INT32(2);	/* typmod for array elements */
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	char		typdelim;
+	Oid			typioparam;
+	char	   *string_save,
+			   *p;
+	int			i,
+				nitems;
+	Datum	   *dataPtr;
+	bool	   *nullsPtr;
+	bool		hasnulls;
+	int32		nbytes;
+	int32		dataoffset;
+	ArrayType  *retval;
+	int			ndim,
+				dim[MAXDIM],
+				lBound[MAXDIM];
+	ArrayMetaState *my_extra;
+
+	/*
+	 * We arrange to look up info about element type, including its input
+	 * conversion proc, only once per series of calls, assuming the element
+	 * type doesn't change underneath us.
+	 */
+	my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL)
+	{
+		fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+													  sizeof(ArrayMetaState));
+		my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+		my_extra->element_type = ~element_type;
+	}
+
+	if (my_extra->element_type != element_type)
+	{
+		/*
+		 * Get info about element type, including its input conversion proc
+		 */
+		get_type_io_data(element_type, IOFunc_input,
+						 &my_extra->typlen, &my_extra->typbyval,
+						 &my_extra->typalign, &my_extra->typdelim,
+						 &my_extra->typioparam, &my_extra->typiofunc);
+		fmgr_info_cxt(my_extra->typiofunc, &my_extra->proc,
+					  fcinfo->flinfo->fn_mcxt);
+		my_extra->element_type = element_type;
+	}
+	typlen = my_extra->typlen;
+	typbyval = my_extra->typbyval;
+	typalign = my_extra->typalign;
+	typdelim = my_extra->typdelim;
+	typioparam = my_extra->typioparam;
+
+	/* Make a modifiable copy of the input */
+	string_save = pstrdup(string);
+
+	/*
+	 * If the input string starts with dimension info, read and use that.
+	 * Otherwise, we require the input to be in curly-brace style, and we
+	 * prescan the input to determine dimensions.
+	 *
+	 * Dimension info takes the form of one or more [n] or [m:n] items. The
+	 * outer loop iterates once per dimension item.
+	 */
+	p = string_save;
+	ndim = 0;
+	for (;;)
+	{
+		char	   *q;
+		int			ub;
+
+		/*
+		 * Note: we currently allow whitespace between, but not within,
+		 * dimension items.
+		 */
+		while (array_isspace(*p))
+			p++;
+		if (*p != '[')
+			break;				/* no more dimension items */
+		p++;
+		if (ndim >= MAXDIM)
+			ereport(ERROR,
+					(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+					 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
+							ndim + 1, MAXDIM)));
+
+		for (q = p; isdigit((unsigned char) *q) || (*q == '-') || (*q == '+'); q++)
+			 /* skip */ ;
+		if (q == p)				/* no digits? */
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("malformed array literal: \"%s\"", string),
+					 errdetail("\"[\" must introduce explicitly-specified array dimensions.")));
+
+		if (*q == ':')
+		{
+			/* [m:n] format */
+			*q = '\0';
+			lBound[ndim] = atoi(p);
+			p = q + 1;
+			for (q = p; isdigit((unsigned char) *q) || (*q == '-') || (*q == '+'); q++)
+				 /* skip */ ;
+			if (q == p)			/* no digits? */
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+						 errmsg("malformed array literal: \"%s\"", string),
+						 errdetail("Missing array dimension value.")));
+		}
+		else
+		{
+			/* [n] format */
+			lBound[ndim] = 1;
+		}
+		if (*q != ']')
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("malformed array literal: \"%s\"", string),
+					 errdetail("Missing \"%s\" after array dimensions.",
+							   "]")));
+
+		*q = '\0';
+		ub = atoi(p);
+		p = q + 1;
+		if (ub < lBound[ndim])
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("upper bound cannot be less than lower bound")));
+
+		dim[ndim] = ub - lBound[ndim] + 1;
+		ndim++;
+	}
+
+	if (ndim == 0)
+	{
+		/* No array dimensions, so intuit dimensions from brace structure */
+		if (*p != '{')
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("malformed array literal: \"%s\"", string),
+					 errdetail("Array value must start with \"{\" or dimension information.")));
+		ndim = ArrayCount(p, dim, typdelim);
+		for (i = 0; i < ndim; i++)
+			lBound[i] = 1;
+	}
+	else
+	{
+		int			ndim_braces,
+					dim_braces[MAXDIM];
+
+		/* If array dimensions are given, expect '=' operator */
+		if (strncmp(p, ASSGN, strlen(ASSGN)) != 0)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("malformed array literal: \"%s\"", string),
+					 errdetail("Missing \"%s\" after array dimensions.",
+							   ASSGN)));
+		p += strlen(ASSGN);
+		while (array_isspace(*p))
+			p++;
+
+		/*
+		 * intuit dimensions from brace structure -- it better match what we
+		 * were given
+		 */
+		if (*p != '{')
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("malformed array literal: \"%s\"", string),
+					 errdetail("Array contents must start with \"{\".")));
+		ndim_braces = ArrayCount(p, dim_braces, typdelim);
+		if (ndim_braces != ndim)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("malformed array literal: \"%s\"", string),
+					 errdetail("Specified array dimensions do not match array contents.")));
+		for (i = 0; i < ndim; ++i)
+		{
+			if (dim[i] != dim_braces[i])
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+						 errmsg("malformed array literal: \"%s\"", string),
+						 errdetail("Specified array dimensions do not match array contents.")));
+		}
+	}
+
+#ifdef ARRAYDEBUG
+	printf("array_in- ndim %d (", ndim);
+	for (i = 0; i < ndim; i++)
+	{
+		printf(" %d", dim[i]);
+	};
+	printf(") for %s\n", string);
+#endif
+
+	/* This checks for overflow of the array dimensions */
+	nitems = ArrayGetNItems(ndim, dim);
+	ArrayCheckBounds(ndim, dim, lBound);
+
+	/* Empty array? */
+	if (nitems == 0)
+		PG_RETURN_ARRAYTYPE_P(construct_empty_array(element_type));
+
+	dataPtr = (Datum *) palloc(nitems * sizeof(Datum));
+	nullsPtr = (bool *) palloc(nitems * sizeof(bool));
+	ReadArrayStr(p, string,
+				 nitems, ndim, dim,
+				 &my_extra->proc, typioparam, typmod,
+				 typdelim,
+				 typlen, typbyval, typalign,
+				 dataPtr, nullsPtr,
+				 &hasnulls, &nbytes);
+	if (hasnulls)
+	{
+		dataoffset = ARR_OVERHEAD_WITHNULLS(ndim, nitems);
+		nbytes += dataoffset;
+	}
+	else
+	{
+		dataoffset = 0;			/* marker for no null bitmap */
+		nbytes += ARR_OVERHEAD_NONULLS(ndim);
+	}
+	retval = (ArrayType *) palloc0(nbytes);
+	SET_VARSIZE(retval, nbytes);
+	retval->ndim = ndim;
+	retval->dataoffset = dataoffset;
+
+	/*
+	 * This comes from the array's pg_type.typelem (which points to the base
+	 * data type's pg_type.oid) and stores system oids in user tables. This
+	 * oid must be preserved by binary upgrades.
+	 */
+	retval->elemtype = element_type;
+	memcpy(ARR_DIMS(retval), dim, ndim * sizeof(int));
+	memcpy(ARR_LBOUND(retval), lBound, ndim * sizeof(int));
+
+	CopyArrayEls(retval,
+				 dataPtr, nullsPtr, nitems,
+				 typlen, typbyval, typalign,
+				 true);
+
+	pfree(dataPtr);
+	pfree(nullsPtr);
+	pfree(string_save);
+
+	PG_RETURN_ARRAYTYPE_P(retval);
+}
+
+/*
+ * array_isspace() --- a non-locale-dependent isspace()
+ *
+ * We used to use isspace() for parsing array values, but that has
+ * undesirable results: an array value might be silently interpreted
+ * differently depending on the locale setting.  Now we just hard-wire
+ * the traditional ASCII definition of isspace().
+ */
+static bool
+array_isspace(char ch)
+{
+	if (ch == ' ' ||
+		ch == '\t' ||
+		ch == '\n' ||
+		ch == '\r' ||
+		ch == '\v' ||
+		ch == '\f')
+		return true;
+	return false;
+}
+
+/*
+ * ArrayCount
+ *	 Determines the dimensions for an array string.
+ *
+ * Returns number of dimensions as function result.  The axis lengths are
+ * returned in dim[], which must be of size MAXDIM.
+ */
+static int
+ArrayCount(const char *str, int *dim, char typdelim)
+{
+	int			nest_level = 0,
+				i;
+	int			ndim = 1,
+				temp[MAXDIM],
+				nelems[MAXDIM],
+				nelems_last[MAXDIM];
+	bool		in_quotes = false;
+	bool		eoArray = false;
+	bool		empty_array = true;
+	const char *ptr;
+	ArrayParseState parse_state = ARRAY_NO_LEVEL;
+
+	for (i = 0; i < MAXDIM; ++i)
+	{
+		temp[i] = dim[i] = nelems_last[i] = 0;
+		nelems[i] = 1;
+	}
+
+	ptr = str;
+	while (!eoArray)
+	{
+		bool		itemdone = false;
+
+		while (!itemdone)
+		{
+			if (parse_state == ARRAY_ELEM_STARTED ||
+				parse_state == ARRAY_QUOTED_ELEM_STARTED)
+				empty_array = false;
+
+			switch (*ptr)
+			{
+				case '\0':
+					/* Signal a premature end of the string */
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+							 errmsg("malformed array literal: \"%s\"", str),
+							 errdetail("Unexpected end of input.")));
+					break;
+				case '\\':
+
+					/*
+					 * An escape must be after a level start, after an element
+					 * start, or after an element delimiter. In any case we
+					 * now must be past an element start.
+					 */
+					if (parse_state != ARRAY_LEVEL_STARTED &&
+						parse_state != ARRAY_ELEM_STARTED &&
+						parse_state != ARRAY_QUOTED_ELEM_STARTED &&
+						parse_state != ARRAY_ELEM_DELIMITED)
+						ereport(ERROR,
+								(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+								 errmsg("malformed array literal: \"%s\"", str),
+								 errdetail("Unexpected \"%c\" character.",
+										   '\\')));
+					if (parse_state != ARRAY_QUOTED_ELEM_STARTED)
+						parse_state = ARRAY_ELEM_STARTED;
+					/* skip the escaped character */
+					if (*(ptr + 1))
+						ptr++;
+					else
+						ereport(ERROR,
+								(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+								 errmsg("malformed array literal: \"%s\"", str),
+								 errdetail("Unexpected end of input.")));
+					break;
+				case '"':
+
+					/*
+					 * A quote must be after a level start, after a quoted
+					 * element start, or after an element delimiter. In any
+					 * case we now must be past an element start.
+					 */
+					if (parse_state != ARRAY_LEVEL_STARTED &&
+						parse_state != ARRAY_QUOTED_ELEM_STARTED &&
+						parse_state != ARRAY_ELEM_DELIMITED)
+						ereport(ERROR,
+								(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+								 errmsg("malformed array literal: \"%s\"", str),
+								 errdetail("Unexpected array element.")));
+					in_quotes = !in_quotes;
+					if (in_quotes)
+						parse_state = ARRAY_QUOTED_ELEM_STARTED;
+					else
+						parse_state = ARRAY_QUOTED_ELEM_COMPLETED;
+					break;
+				case '{':
+					if (!in_quotes)
+					{
+						/*
+						 * A left brace can occur if no nesting has occurred
+						 * yet, after a level start, or after a level
+						 * delimiter.
+						 */
+						if (parse_state != ARRAY_NO_LEVEL &&
+							parse_state != ARRAY_LEVEL_STARTED &&
+							parse_state != ARRAY_LEVEL_DELIMITED)
+							ereport(ERROR,
+									(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+									 errmsg("malformed array literal: \"%s\"", str),
+									 errdetail("Unexpected \"%c\" character.",
+											   '{')));
+						parse_state = ARRAY_LEVEL_STARTED;
+						if (nest_level >= MAXDIM)
+							ereport(ERROR,
+									(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+									 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
+											nest_level + 1, MAXDIM)));
+						temp[nest_level] = 0;
+						nest_level++;
+						if (ndim < nest_level)
+							ndim = nest_level;
+					}
+					break;
+				case '}':
+					if (!in_quotes)
+					{
+						/*
+						 * A right brace can occur after an element start, an
+						 * element completion, a quoted element completion, or
+						 * a level completion.
+						 */
+						if (parse_state != ARRAY_ELEM_STARTED &&
+							parse_state != ARRAY_ELEM_COMPLETED &&
+							parse_state != ARRAY_QUOTED_ELEM_COMPLETED &&
+							parse_state != ARRAY_LEVEL_COMPLETED &&
+							!(nest_level == 1 && parse_state == ARRAY_LEVEL_STARTED))
+							ereport(ERROR,
+									(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+									 errmsg("malformed array literal: \"%s\"", str),
+									 errdetail("Unexpected \"%c\" character.",
+											   '}')));
+						parse_state = ARRAY_LEVEL_COMPLETED;
+						if (nest_level == 0)
+							ereport(ERROR,
+									(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+									 errmsg("malformed array literal: \"%s\"", str),
+									 errdetail("Unmatched \"%c\" character.", '}')));
+						nest_level--;
+
+						if (nelems_last[nest_level] != 0 &&
+							nelems[nest_level] != nelems_last[nest_level])
+							ereport(ERROR,
+									(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+									 errmsg("malformed array literal: \"%s\"", str),
+									 errdetail("Multidimensional arrays must have "
+											   "sub-arrays with matching "
+											   "dimensions.")));
+						nelems_last[nest_level] = nelems[nest_level];
+						nelems[nest_level] = 1;
+						if (nest_level == 0)
+							eoArray = itemdone = true;
+						else
+						{
+							/*
+							 * We don't set itemdone here; see comments in
+							 * ReadArrayStr
+							 */
+							temp[nest_level - 1]++;
+						}
+					}
+					break;
+				default:
+					if (!in_quotes)
+					{
+						if (*ptr == typdelim)
+						{
+							/*
+							 * Delimiters can occur after an element start, an
+							 * element completion, a quoted element
+							 * completion, or a level completion.
+							 */
+							if (parse_state != ARRAY_ELEM_STARTED &&
+								parse_state != ARRAY_ELEM_COMPLETED &&
+								parse_state != ARRAY_QUOTED_ELEM_COMPLETED &&
+								parse_state != ARRAY_LEVEL_COMPLETED)
+								ereport(ERROR,
+										(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+										 errmsg("malformed array literal: \"%s\"", str),
+										 errdetail("Unexpected \"%c\" character.",
+												   typdelim)));
+							if (parse_state == ARRAY_LEVEL_COMPLETED)
+								parse_state = ARRAY_LEVEL_DELIMITED;
+							else
+								parse_state = ARRAY_ELEM_DELIMITED;
+							itemdone = true;
+							nelems[nest_level - 1]++;
+						}
+						else if (!array_isspace(*ptr))
+						{
+							/*
+							 * Other non-space characters must be after a
+							 * level start, after an element start, or after
+							 * an element delimiter. In any case we now must
+							 * be past an element start.
+							 */
+							if (parse_state != ARRAY_LEVEL_STARTED &&
+								parse_state != ARRAY_ELEM_STARTED &&
+								parse_state != ARRAY_ELEM_DELIMITED)
+								ereport(ERROR,
+										(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+										 errmsg("malformed array literal: \"%s\"", str),
+										 errdetail("Unexpected array element.")));
+							parse_state = ARRAY_ELEM_STARTED;
+						}
+					}
+					break;
+			}
+			if (!itemdone)
+				ptr++;
+		}
+		temp[ndim - 1]++;
+		ptr++;
+	}
+
+	/* only whitespace is allowed after the closing brace */
+	while (*ptr)
+	{
+		if (!array_isspace(*ptr++))
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("malformed array literal: \"%s\"", str),
+					 errdetail("Junk after closing right brace.")));
+	}
+
+	/* special case for an empty array */
+	if (empty_array)
+		return 0;
+
+	for (i = 0; i < ndim; ++i)
+		dim[i] = temp[i];
+
+	return ndim;
+}
+
+/*
+ * ReadArrayStr :
+ *	 parses the array string pointed to by "arrayStr" and converts the values
+ *	 to internal format.  Unspecified elements are initialized to nulls.
+ *	 The array dimensions must already have been determined.
+ *
+ * Inputs:
+ *	arrayStr: the string to parse.
+ *			  CAUTION: the contents of "arrayStr" will be modified!
+ *	origStr: the unmodified input string, used only in error messages.
+ *	nitems: total number of array elements, as already determined.
+ *	ndim: number of array dimensions
+ *	dim[]: array axis lengths
+ *	inputproc: type-specific input procedure for element datatype.
+ *	typioparam, typmod: auxiliary values to pass to inputproc.
+ *	typdelim: the value delimiter (type-specific).
+ *	typlen, typbyval, typalign: storage parameters of element datatype.
+ *
+ * Outputs:
+ *	values[]: filled with converted data values.
+ *	nulls[]: filled with is-null markers.
+ *	*hasnulls: set true iff there are any null elements.
+ *	*nbytes: set to total size of data area needed (including alignment
+ *		padding but not including array header overhead).
+ *
+ * Note that values[] and nulls[] are allocated by the caller, and must have
+ * nitems elements.
+ */
+static void
+ReadArrayStr(char *arrayStr,
+			 const char *origStr,
+			 int nitems,
+			 int ndim,
+			 int *dim,
+			 FmgrInfo *inputproc,
+			 Oid typioparam,
+			 int32 typmod,
+			 char typdelim,
+			 int typlen,
+			 bool typbyval,
+			 char typalign,
+			 Datum *values,
+			 bool *nulls,
+			 bool *hasnulls,
+			 int32 *nbytes)
+{
+	int			i,
+				nest_level = 0;
+	char	   *srcptr;
+	bool		in_quotes = false;
+	bool		eoArray = false;
+	bool		hasnull;
+	int32		totbytes;
+	int			indx[MAXDIM],
+				prod[MAXDIM];
+
+	mda_get_prod(ndim, dim, prod);
+	MemSet(indx, 0, sizeof(indx));
+
+	/* Initialize is-null markers to true */
+	memset(nulls, true, nitems * sizeof(bool));
+
+	/*
+	 * We have to remove " and \ characters to create a clean item value to
+	 * pass to the datatype input routine.  We overwrite each item value
+	 * in-place within arrayStr to do this.  srcptr is the current scan point,
+	 * and dstptr is where we are copying to.
+	 *
+	 * We also want to suppress leading and trailing unquoted whitespace. We
+	 * use the leadingspace flag to suppress leading space.  Trailing space is
+	 * tracked by using dstendptr to point to the last significant output
+	 * character.
+	 *
+	 * The error checking in this routine is mostly pro-forma, since we expect
+	 * that ArrayCount() already validated the string.  So we don't bother
+	 * with errdetail messages.
+	 */
+	srcptr = arrayStr;
+	while (!eoArray)
+	{
+		bool		itemdone = false;
+		bool		leadingspace = true;
+		bool		hasquoting = false;
+		char	   *itemstart;
+		char	   *dstptr;
+		char	   *dstendptr;
+
+		i = -1;
+		itemstart = dstptr = dstendptr = srcptr;
+
+		while (!itemdone)
+		{
+			switch (*srcptr)
+			{
+				case '\0':
+					/* Signal a premature end of the string */
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+							 errmsg("malformed array literal: \"%s\"",
+									origStr)));
+					break;
+				case '\\':
+					/* Skip backslash, copy next character as-is. */
+					srcptr++;
+					if (*srcptr == '\0')
+						ereport(ERROR,
+								(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+								 errmsg("malformed array literal: \"%s\"",
+										origStr)));
+					*dstptr++ = *srcptr++;
+					/* Treat the escaped character as non-whitespace */
+					leadingspace = false;
+					dstendptr = dstptr;
+					hasquoting = true;	/* can't be a NULL marker */
+					break;
+				case '"':
+					in_quotes = !in_quotes;
+					if (in_quotes)
+						leadingspace = false;
+					else
+					{
+						/*
+						 * Advance dstendptr when we exit in_quotes; this
+						 * saves having to do it in all the other in_quotes
+						 * cases.
+						 */
+						dstendptr = dstptr;
+					}
+					hasquoting = true;	/* can't be a NULL marker */
+					srcptr++;
+					break;
+				case '{':
+					if (!in_quotes)
+					{
+						if (nest_level >= ndim)
+							ereport(ERROR,
+									(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+									 errmsg("malformed array literal: \"%s\"",
+											origStr)));
+						nest_level++;
+						indx[nest_level - 1] = 0;
+						srcptr++;
+					}
+					else
+						*dstptr++ = *srcptr++;
+					break;
+				case '}':
+					if (!in_quotes)
+					{
+						if (nest_level == 0)
+							ereport(ERROR,
+									(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+									 errmsg("malformed array literal: \"%s\"",
+											origStr)));
+						if (i == -1)
+							i = ArrayGetOffset0(ndim, indx, prod);
+						indx[nest_level - 1] = 0;
+						nest_level--;
+						if (nest_level == 0)
+							eoArray = itemdone = true;
+						else
+							indx[nest_level - 1]++;
+						srcptr++;
+					}
+					else
+						*dstptr++ = *srcptr++;
+					break;
+				default:
+					if (in_quotes)
+						*dstptr++ = *srcptr++;
+					else if (*srcptr == typdelim)
+					{
+						if (i == -1)
+							i = ArrayGetOffset0(ndim, indx, prod);
+						itemdone = true;
+						indx[ndim - 1]++;
+						srcptr++;
+					}
+					else if (array_isspace(*srcptr))
+					{
+						/*
+						 * If leading space, drop it immediately.  Else, copy
+						 * but don't advance dstendptr.
+						 */
+						if (leadingspace)
+							srcptr++;
+						else
+							*dstptr++ = *srcptr++;
+					}
+					else
+					{
+						*dstptr++ = *srcptr++;
+						leadingspace = false;
+						dstendptr = dstptr;
+					}
+					break;
+			}
+		}
+
+		Assert(dstptr < srcptr);
+		*dstendptr = '\0';
+
+		if (i < 0 || i >= nitems)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("malformed array literal: \"%s\"",
+							origStr)));
+
+		if (Array_nulls && !hasquoting &&
+			pg_strcasecmp(itemstart, "NULL") == 0)
+		{
+			/* it's a NULL item */
+			values[i] = InputFunctionCall(inputproc, NULL,
+										  typioparam, typmod);
+			nulls[i] = true;
+		}
+		else
+		{
+			values[i] = InputFunctionCall(inputproc, itemstart,
+										  typioparam, typmod);
+			nulls[i] = false;
+		}
+	}
+
+	/*
+	 * Check for nulls, compute total data space needed
+	 */
+	hasnull = false;
+	totbytes = 0;
+	for (i = 0; i < nitems; i++)
+	{
+		if (nulls[i])
+			hasnull = true;
+		else
+		{
+			/* let's just make sure data is not toasted */
+			if (typlen == -1)
+				values[i] = PointerGetDatum(PG_DETOAST_DATUM(values[i]));
+			totbytes = att_addlength_datum(totbytes, typlen, values[i]);
+			totbytes = att_align_nominal(totbytes, typalign);
+			/* check for overflow of total request */
+			if (!AllocSizeIsValid(totbytes))
+				ereport(ERROR,
+						(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+						 errmsg("array size exceeds the maximum allowed (%d)",
+								(int) MaxAllocSize)));
+		}
+	}
+	*hasnulls = hasnull;
+	*nbytes = totbytes;
+}
+
+
+/*
+ * Copy data into an array object from a temporary array of Datums.
+ *
+ * array: array object (with header fields already filled in)
+ * values: array of Datums to be copied
+ * nulls: array of is-null flags (can be NULL if no nulls)
+ * nitems: number of Datums to be copied
+ * typbyval, typlen, typalign: info about element datatype
+ * freedata: if true and element type is pass-by-ref, pfree data values
+ * referenced by Datums after copying them.
+ *
+ * If the input data is of varlena type, the caller must have ensured that
+ * the values are not toasted.  (Doing it here doesn't work since the
+ * caller has already allocated space for the array...)
+ */
+void
+CopyArrayEls(ArrayType *array,
+			 Datum *values,
+			 bool *nulls,
+			 int nitems,
+			 int typlen,
+			 bool typbyval,
+			 char typalign,
+			 bool freedata)
+{
+	char	   *p = ARR_DATA_PTR(array);
+	bits8	   *bitmap = ARR_NULLBITMAP(array);
+	int			bitval = 0;
+	int			bitmask = 1;
+	int			i;
+
+	if (typbyval)
+		freedata = false;
+
+	for (i = 0; i < nitems; i++)
+	{
+		if (nulls && nulls[i])
+		{
+			if (!bitmap)		/* shouldn't happen */
+				elog(ERROR, "null array element where not supported");
+			/* bitmap bit stays 0 */
+		}
+		else
+		{
+			bitval |= bitmask;
+			p += ArrayCastAndSet(values[i], typlen, typbyval, typalign, p);
+			if (freedata)
+				pfree(DatumGetPointer(values[i]));
+		}
+		if (bitmap)
+		{
+			bitmask <<= 1;
+			if (bitmask == 0x100)
+			{
+				*bitmap++ = bitval;
+				bitval = 0;
+				bitmask = 1;
+			}
+		}
+	}
+
+	if (bitmap && bitmask != 1)
+		*bitmap = bitval;
+}
+
+/*
+ * array_out :
+ *		   takes the internal representation of an array and returns a string
+ *		  containing the array in its external format.
+ */
+Datum
+array_out(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+	Oid			element_type = AARR_ELEMTYPE(v);
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	char		typdelim;
+	char	   *p,
+			   *tmp,
+			   *retval,
+			  **values,
+				dims_str[(MAXDIM * 33) + 2];
+
+	/*
+	 * 33 per dim since we assume 15 digits per number + ':' +'[]'
+	 *
+	 * +2 allows for assignment operator + trailing null
+	 */
+	bool	   *needquotes,
+				needdims = false;
+	size_t		overall_length;
+	int			nitems,
+				i,
+				j,
+				k,
+				indx[MAXDIM];
+	int			ndim,
+			   *dims,
+			   *lb;
+	array_iter	iter;
+	ArrayMetaState *my_extra;
+
+	/*
+	 * We arrange to look up info about element type, including its output
+	 * conversion proc, only once per series of calls, assuming the element
+	 * type doesn't change underneath us.
+	 */
+	my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL)
+	{
+		fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+													  sizeof(ArrayMetaState));
+		my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+		my_extra->element_type = ~element_type;
+	}
+
+	if (my_extra->element_type != element_type)
+	{
+		/*
+		 * Get info about element type, including its output conversion proc
+		 */
+		get_type_io_data(element_type, IOFunc_output,
+						 &my_extra->typlen, &my_extra->typbyval,
+						 &my_extra->typalign, &my_extra->typdelim,
+						 &my_extra->typioparam, &my_extra->typiofunc);
+		fmgr_info_cxt(my_extra->typiofunc, &my_extra->proc,
+					  fcinfo->flinfo->fn_mcxt);
+		my_extra->element_type = element_type;
+	}
+	typlen = my_extra->typlen;
+	typbyval = my_extra->typbyval;
+	typalign = my_extra->typalign;
+	typdelim = my_extra->typdelim;
+
+	ndim = AARR_NDIM(v);
+	dims = AARR_DIMS(v);
+	lb = AARR_LBOUND(v);
+	nitems = ArrayGetNItems(ndim, dims);
+
+	if (nitems == 0)
+	{
+		retval = pstrdup("{}");
+		PG_RETURN_CSTRING(retval);
+	}
+
+	/*
+	 * we will need to add explicit dimensions if any dimension has a lower
+	 * bound other than one
+	 */
+	for (i = 0; i < ndim; i++)
+	{
+		if (lb[i] != 1)
+		{
+			needdims = true;
+			break;
+		}
+	}
+
+	/*
+	 * Convert all values to string form, count total space needed (including
+	 * any overhead such as escaping backslashes), and detect whether each
+	 * item needs double quotes.
+	 */
+	values = (char **) palloc(nitems * sizeof(char *));
+	needquotes = (bool *) palloc(nitems * sizeof(bool));
+	overall_length = 0;
+
+	array_iter_setup(&iter, v);
+
+	for (i = 0; i < nitems; i++)
+	{
+		Datum		itemvalue;
+		bool		isnull;
+		bool		needquote;
+
+		/* Get source element, checking for NULL */
+		itemvalue = array_iter_next(&iter, &isnull, i,
+									typlen, typbyval, typalign);
+
+		if (isnull)
+		{
+			values[i] = pstrdup("NULL");
+			overall_length += 4;
+			needquote = false;
+		}
+		else
+		{
+			values[i] = OutputFunctionCall(&my_extra->proc, itemvalue);
+
+			/* count data plus backslashes; detect chars needing quotes */
+			if (values[i][0] == '\0')
+				needquote = true;	/* force quotes for empty string */
+			else if (pg_strcasecmp(values[i], "NULL") == 0)
+				needquote = true;	/* force quotes for literal NULL */
+			else
+				needquote = false;
+
+			for (tmp = values[i]; *tmp != '\0'; tmp++)
+			{
+				char		ch = *tmp;
+
+				overall_length += 1;
+				if (ch == '"' || ch == '\\')
+				{
+					needquote = true;
+					overall_length += 1;
+				}
+				else if (ch == '{' || ch == '}' || ch == typdelim ||
+						 array_isspace(ch))
+					needquote = true;
+			}
+		}
+
+		needquotes[i] = needquote;
+
+		/* Count the pair of double quotes, if needed */
+		if (needquote)
+			overall_length += 2;
+		/* and the comma (or other typdelim delimiter) */
+		overall_length += 1;
+	}
+
+	/*
+	 * The very last array element doesn't have a typdelim delimiter after it,
+	 * but that's OK; that space is needed for the trailing '\0'.
+	 *
+	 * Now count total number of curly brace pairs in output string.
+	 */
+	for (i = j = 0, k = 1; i < ndim; i++)
+	{
+		j += k, k *= dims[i];
+	}
+	overall_length += 2 * j;
+
+	/* Format explicit dimensions if required */
+	dims_str[0] = '\0';
+	if (needdims)
+	{
+		char	   *ptr = dims_str;
+
+		for (i = 0; i < ndim; i++)
+		{
+			sprintf(ptr, "[%d:%d]", lb[i], lb[i] + dims[i] - 1);
+			ptr += strlen(ptr);
+		}
+		*ptr++ = *ASSGN;
+		*ptr = '\0';
+		overall_length += ptr - dims_str;
+	}
+
+	/* Now construct the output string */
+	retval = (char *) palloc(overall_length);
+	p = retval;
+
+#define APPENDSTR(str)	(strcpy(p, (str)), p += strlen(p))
+#define APPENDCHAR(ch)	(*p++ = (ch), *p = '\0')
+
+	if (needdims)
+		APPENDSTR(dims_str);
+	APPENDCHAR('{');
+	for (i = 0; i < ndim; i++)
+		indx[i] = 0;
+	j = 0;
+	k = 0;
+	do
+	{
+		for (i = j; i < ndim - 1; i++)
+			APPENDCHAR('{');
+
+		if (needquotes[k])
+		{
+			APPENDCHAR('"');
+			for (tmp = values[k]; *tmp; tmp++)
+			{
+				char		ch = *tmp;
+
+				if (ch == '"' || ch == '\\')
+					*p++ = '\\';
+				*p++ = ch;
+			}
+			*p = '\0';
+			APPENDCHAR('"');
+		}
+		else
+			APPENDSTR(values[k]);
+		pfree(values[k++]);
+
+		for (i = ndim - 1; i >= 0; i--)
+		{
+			if (++(indx[i]) < dims[i])
+			{
+				APPENDCHAR(typdelim);
+				break;
+			}
+			else
+			{
+				indx[i] = 0;
+				APPENDCHAR('}');
+			}
+		}
+		j = i;
+	} while (j != -1);
+
+#undef APPENDSTR
+#undef APPENDCHAR
+
+	/* Assert that we calculated the string length accurately */
+	Assert(overall_length == (p - retval + 1));
+
+	pfree(values);
+	pfree(needquotes);
+
+	PG_RETURN_CSTRING(retval);
+}
+
+/*
+ * array_recv :
+ *		  converts an array from the external binary format to
+ *		  its internal format.
+ *
+ * return value :
+ *		  the internal representation of the input array
+ */
+Datum
+array_recv(PG_FUNCTION_ARGS)
+{
+	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);
+	Oid			spec_element_type = PG_GETARG_OID(1);	/* type of an array
+														 * element */
+	int32		typmod = PG_GETARG_INT32(2);	/* typmod for array elements */
+	Oid			element_type;
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	Oid			typioparam;
+	int			i,
+				nitems;
+	Datum	   *dataPtr;
+	bool	   *nullsPtr;
+	bool		hasnulls;
+	int32		nbytes;
+	int32		dataoffset;
+	ArrayType  *retval;
+	int			ndim,
+				flags,
+				dim[MAXDIM],
+				lBound[MAXDIM];
+	ArrayMetaState *my_extra;
+
+	/* Get the array header information */
+	ndim = pq_getmsgint(buf, 4);
+	if (ndim < 0)				/* we do allow zero-dimension arrays */
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
+				 errmsg("invalid number of dimensions: %d", ndim)));
+	if (ndim > MAXDIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+				 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
+						ndim, MAXDIM)));
+
+	flags = pq_getmsgint(buf, 4);
+	if (flags != 0 && flags != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
+				 errmsg("invalid array flags")));
+
+	/* Check element type recorded in the data */
+	element_type = pq_getmsgint(buf, sizeof(Oid));
+
+	/*
+	 * From a security standpoint, it doesn't matter whether the input's
+	 * element type matches what we expect: the element type's receive
+	 * function has to be robust enough to cope with invalid data.  However,
+	 * from a user-friendliness standpoint, it's nicer to complain about type
+	 * mismatches than to throw "improper binary format" errors.  But there's
+	 * a problem: only built-in types have OIDs that are stable enough to
+	 * believe that a mismatch is a real issue.  So complain only if both OIDs
+	 * are in the built-in range.  Otherwise, carry on with the element type
+	 * we "should" be getting.
+	 */
+	if (element_type != spec_element_type)
+	{
+		if (element_type < FirstGenbkiObjectId &&
+			spec_element_type < FirstGenbkiObjectId)
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("binary data has array element type %u (%s) instead of expected %u (%s)",
+							element_type,
+							format_type_extended(element_type, -1,
+												 FORMAT_TYPE_ALLOW_INVALID),
+							spec_element_type,
+							format_type_extended(spec_element_type, -1,
+												 FORMAT_TYPE_ALLOW_INVALID))));
+		element_type = spec_element_type;
+	}
+
+	for (i = 0; i < ndim; i++)
+	{
+		dim[i] = pq_getmsgint(buf, 4);
+		lBound[i] = pq_getmsgint(buf, 4);
+	}
+
+	/* This checks for overflow of array dimensions */
+	nitems = ArrayGetNItems(ndim, dim);
+	ArrayCheckBounds(ndim, dim, lBound);
+
+	/*
+	 * We arrange to look up info about element type, including its receive
+	 * conversion proc, only once per series of calls, assuming the element
+	 * type doesn't change underneath us.
+	 */
+	my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL)
+	{
+		fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+													  sizeof(ArrayMetaState));
+		my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+		my_extra->element_type = ~element_type;
+	}
+
+	if (my_extra->element_type != element_type)
+	{
+		/* Get info about element type, including its receive proc */
+		get_type_io_data(element_type, IOFunc_receive,
+						 &my_extra->typlen, &my_extra->typbyval,
+						 &my_extra->typalign, &my_extra->typdelim,
+						 &my_extra->typioparam, &my_extra->typiofunc);
+		if (!OidIsValid(my_extra->typiofunc))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("no binary input function available for type %s",
+							format_type_be(element_type))));
+		fmgr_info_cxt(my_extra->typiofunc, &my_extra->proc,
+					  fcinfo->flinfo->fn_mcxt);
+		my_extra->element_type = element_type;
+	}
+
+	if (nitems == 0)
+	{
+		/* Return empty array ... but not till we've validated element_type */
+		PG_RETURN_ARRAYTYPE_P(construct_empty_array(element_type));
+	}
+
+	typlen = my_extra->typlen;
+	typbyval = my_extra->typbyval;
+	typalign = my_extra->typalign;
+	typioparam = my_extra->typioparam;
+
+	dataPtr = (Datum *) palloc(nitems * sizeof(Datum));
+	nullsPtr = (bool *) palloc(nitems * sizeof(bool));
+	ReadArrayBinary(buf, nitems,
+					&my_extra->proc, typioparam, typmod,
+					typlen, typbyval, typalign,
+					dataPtr, nullsPtr,
+					&hasnulls, &nbytes);
+	if (hasnulls)
+	{
+		dataoffset = ARR_OVERHEAD_WITHNULLS(ndim, nitems);
+		nbytes += dataoffset;
+	}
+	else
+	{
+		dataoffset = 0;			/* marker for no null bitmap */
+		nbytes += ARR_OVERHEAD_NONULLS(ndim);
+	}
+	retval = (ArrayType *) palloc0(nbytes);
+	SET_VARSIZE(retval, nbytes);
+	retval->ndim = ndim;
+	retval->dataoffset = dataoffset;
+	retval->elemtype = element_type;
+	memcpy(ARR_DIMS(retval), dim, ndim * sizeof(int));
+	memcpy(ARR_LBOUND(retval), lBound, ndim * sizeof(int));
+
+	CopyArrayEls(retval,
+				 dataPtr, nullsPtr, nitems,
+				 typlen, typbyval, typalign,
+				 true);
+
+	pfree(dataPtr);
+	pfree(nullsPtr);
+
+	PG_RETURN_ARRAYTYPE_P(retval);
+}
+
+/*
+ * ReadArrayBinary:
+ *	 collect the data elements of an array being read in binary style.
+ *
+ * Inputs:
+ *	buf: the data buffer to read from.
+ *	nitems: total number of array elements (already read).
+ *	receiveproc: type-specific receive procedure for element datatype.
+ *	typioparam, typmod: auxiliary values to pass to receiveproc.
+ *	typlen, typbyval, typalign: storage parameters of element datatype.
+ *
+ * Outputs:
+ *	values[]: filled with converted data values.
+ *	nulls[]: filled with is-null markers.
+ *	*hasnulls: set true iff there are any null elements.
+ *	*nbytes: set to total size of data area needed (including alignment
+ *		padding but not including array header overhead).
+ *
+ * Note that values[] and nulls[] are allocated by the caller, and must have
+ * nitems elements.
+ */
+static void
+ReadArrayBinary(StringInfo buf,
+				int nitems,
+				FmgrInfo *receiveproc,
+				Oid typioparam,
+				int32 typmod,
+				int typlen,
+				bool typbyval,
+				char typalign,
+				Datum *values,
+				bool *nulls,
+				bool *hasnulls,
+				int32 *nbytes)
+{
+	int			i;
+	bool		hasnull;
+	int32		totbytes;
+
+	for (i = 0; i < nitems; i++)
+	{
+		int			itemlen;
+		StringInfoData elem_buf;
+		char		csave;
+
+		/* Get and check the item length */
+		itemlen = pq_getmsgint(buf, 4);
+		if (itemlen < -1 || itemlen > (buf->len - buf->cursor))
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
+					 errmsg("insufficient data left in message")));
+
+		if (itemlen == -1)
+		{
+			/* -1 length means NULL */
+			values[i] = ReceiveFunctionCall(receiveproc, NULL,
+											typioparam, typmod);
+			nulls[i] = true;
+			continue;
+		}
+
+		/*
+		 * Rather than copying data around, we just set up a phony StringInfo
+		 * pointing to the correct portion of the input buffer. We assume we
+		 * can scribble on the input buffer so as to maintain the convention
+		 * that StringInfos have a trailing null.
+		 */
+		elem_buf.data = &buf->data[buf->cursor];
+		elem_buf.maxlen = itemlen + 1;
+		elem_buf.len = itemlen;
+		elem_buf.cursor = 0;
+
+		buf->cursor += itemlen;
+
+		csave = buf->data[buf->cursor];
+		buf->data[buf->cursor] = '\0';
+
+		/* Now call the element's receiveproc */
+		values[i] = ReceiveFunctionCall(receiveproc, &elem_buf,
+										typioparam, typmod);
+		nulls[i] = false;
+
+		/* Trouble if it didn't eat the whole buffer */
+		if (elem_buf.cursor != itemlen)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
+					 errmsg("improper binary format in array element %d",
+							i + 1)));
+
+		buf->data[buf->cursor] = csave;
+	}
+
+	/*
+	 * Check for nulls, compute total data space needed
+	 */
+	hasnull = false;
+	totbytes = 0;
+	for (i = 0; i < nitems; i++)
+	{
+		if (nulls[i])
+			hasnull = true;
+		else
+		{
+			/* let's just make sure data is not toasted */
+			if (typlen == -1)
+				values[i] = PointerGetDatum(PG_DETOAST_DATUM(values[i]));
+			totbytes = att_addlength_datum(totbytes, typlen, values[i]);
+			totbytes = att_align_nominal(totbytes, typalign);
+			/* check for overflow of total request */
+			if (!AllocSizeIsValid(totbytes))
+				ereport(ERROR,
+						(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+						 errmsg("array size exceeds the maximum allowed (%d)",
+								(int) MaxAllocSize)));
+		}
+	}
+	*hasnulls = hasnull;
+	*nbytes = totbytes;
+}
+
+
+/*
+ * array_send :
+ *		  takes the internal representation of an array and returns a bytea
+ *		  containing the array in its external binary format.
+ */
+Datum
+array_send(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+	Oid			element_type = AARR_ELEMTYPE(v);
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	int			nitems,
+				i;
+	int			ndim,
+			   *dim,
+			   *lb;
+	StringInfoData buf;
+	array_iter	iter;
+	ArrayMetaState *my_extra;
+
+	/*
+	 * We arrange to look up info about element type, including its send
+	 * conversion proc, only once per series of calls, assuming the element
+	 * type doesn't change underneath us.
+	 */
+	my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL)
+	{
+		fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+													  sizeof(ArrayMetaState));
+		my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+		my_extra->element_type = ~element_type;
+	}
+
+	if (my_extra->element_type != element_type)
+	{
+		/* Get info about element type, including its send proc */
+		get_type_io_data(element_type, IOFunc_send,
+						 &my_extra->typlen, &my_extra->typbyval,
+						 &my_extra->typalign, &my_extra->typdelim,
+						 &my_extra->typioparam, &my_extra->typiofunc);
+		if (!OidIsValid(my_extra->typiofunc))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("no binary output function available for type %s",
+							format_type_be(element_type))));
+		fmgr_info_cxt(my_extra->typiofunc, &my_extra->proc,
+					  fcinfo->flinfo->fn_mcxt);
+		my_extra->element_type = element_type;
+	}
+	typlen = my_extra->typlen;
+	typbyval = my_extra->typbyval;
+	typalign = my_extra->typalign;
+
+	ndim = AARR_NDIM(v);
+	dim = AARR_DIMS(v);
+	lb = AARR_LBOUND(v);
+	nitems = ArrayGetNItems(ndim, dim);
+
+	pq_begintypsend(&buf);
+
+	/* Send the array header information */
+	pq_sendint32(&buf, ndim);
+	pq_sendint32(&buf, AARR_HASNULL(v) ? 1 : 0);
+	pq_sendint32(&buf, element_type);
+	for (i = 0; i < ndim; i++)
+	{
+		pq_sendint32(&buf, dim[i]);
+		pq_sendint32(&buf, lb[i]);
+	}
+
+	/* Send the array elements using the element's own sendproc */
+	array_iter_setup(&iter, v);
+
+	for (i = 0; i < nitems; i++)
+	{
+		Datum		itemvalue;
+		bool		isnull;
+
+		/* Get source element, checking for NULL */
+		itemvalue = array_iter_next(&iter, &isnull, i,
+									typlen, typbyval, typalign);
+
+		if (isnull)
+		{
+			/* -1 length means a NULL */
+			pq_sendint32(&buf, -1);
+		}
+		else
+		{
+			bytea	   *outputbytes;
+
+			outputbytes = SendFunctionCall(&my_extra->proc, itemvalue);
+			pq_sendint32(&buf, VARSIZE(outputbytes) - VARHDRSZ);
+			pq_sendbytes(&buf, VARDATA(outputbytes),
+						 VARSIZE(outputbytes) - VARHDRSZ);
+			pfree(outputbytes);
+		}
+	}
+
+	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
+}
+
+/*
+ * array_ndims :
+ *		  returns the number of dimensions of the array pointed to by "v"
+ */
+Datum
+array_ndims(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+
+	/* Sanity check: does it look like an array at all? */
+	if (AARR_NDIM(v) <= 0 || AARR_NDIM(v) > MAXDIM)
+		PG_RETURN_NULL();
+
+	PG_RETURN_INT32(AARR_NDIM(v));
+}
+
+/*
+ * array_dims :
+ *		  returns the dimensions of the array pointed to by "v", as a "text"
+ */
+Datum
+array_dims(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+	char	   *p;
+	int			i;
+	int		   *dimv,
+			   *lb;
+
+	/*
+	 * 33 since we assume 15 digits per number + ':' +'[]'
+	 *
+	 * +1 for trailing null
+	 */
+	char		buf[MAXDIM * 33 + 1];
+
+	/* Sanity check: does it look like an array at all? */
+	if (AARR_NDIM(v) <= 0 || AARR_NDIM(v) > MAXDIM)
+		PG_RETURN_NULL();
+
+	dimv = AARR_DIMS(v);
+	lb = AARR_LBOUND(v);
+
+	p = buf;
+	for (i = 0; i < AARR_NDIM(v); i++)
+	{
+		sprintf(p, "[%d:%d]", lb[i], dimv[i] + lb[i] - 1);
+		p += strlen(p);
+	}
+
+	PG_RETURN_TEXT_P(cstring_to_text(buf));
+}
+
+/*
+ * array_lower :
+ *		returns the lower dimension, of the DIM requested, for
+ *		the array pointed to by "v", as an int4
+ */
+Datum
+array_lower(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+	int			reqdim = PG_GETARG_INT32(1);
+	int		   *lb;
+	int			result;
+
+	/* Sanity check: does it look like an array at all? */
+	if (AARR_NDIM(v) <= 0 || AARR_NDIM(v) > MAXDIM)
+		PG_RETURN_NULL();
+
+	/* Sanity check: was the requested dim valid */
+	if (reqdim <= 0 || reqdim > AARR_NDIM(v))
+		PG_RETURN_NULL();
+
+	lb = AARR_LBOUND(v);
+	result = lb[reqdim - 1];
+
+	PG_RETURN_INT32(result);
+}
+
+/*
+ * array_upper :
+ *		returns the upper dimension, of the DIM requested, for
+ *		the array pointed to by "v", as an int4
+ */
+Datum
+array_upper(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+	int			reqdim = PG_GETARG_INT32(1);
+	int		   *dimv,
+			   *lb;
+	int			result;
+
+	/* Sanity check: does it look like an array at all? */
+	if (AARR_NDIM(v) <= 0 || AARR_NDIM(v) > MAXDIM)
+		PG_RETURN_NULL();
+
+	/* Sanity check: was the requested dim valid */
+	if (reqdim <= 0 || reqdim > AARR_NDIM(v))
+		PG_RETURN_NULL();
+
+	lb = AARR_LBOUND(v);
+	dimv = AARR_DIMS(v);
+
+	result = dimv[reqdim - 1] + lb[reqdim - 1] - 1;
+
+	PG_RETURN_INT32(result);
+}
+
+/*
+ * array_length :
+ *		returns the length, of the dimension requested, for
+ *		the array pointed to by "v", as an int4
+ */
+Datum
+array_length(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+	int			reqdim = PG_GETARG_INT32(1);
+	int		   *dimv;
+	int			result;
+
+	/* Sanity check: does it look like an array at all? */
+	if (AARR_NDIM(v) <= 0 || AARR_NDIM(v) > MAXDIM)
+		PG_RETURN_NULL();
+
+	/* Sanity check: was the requested dim valid */
+	if (reqdim <= 0 || reqdim > AARR_NDIM(v))
+		PG_RETURN_NULL();
+
+	dimv = AARR_DIMS(v);
+
+	result = dimv[reqdim - 1];
+
+	PG_RETURN_INT32(result);
+}
+
+/*
+ * array_cardinality:
+ *		returns the total number of elements in an array
+ */
+Datum
+array_cardinality(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+
+	PG_RETURN_INT32(ArrayGetNItems(AARR_NDIM(v), AARR_DIMS(v)));
+}
+
+
+/*
+ * array_get_element :
+ *	  This routine takes an array datum and a subscript array and returns
+ *	  the referenced item as a Datum.  Note that for a pass-by-reference
+ *	  datatype, the returned Datum is a pointer into the array object.
+ *
+ * This handles both ordinary varlena arrays and fixed-length arrays.
+ *
+ * Inputs:
+ *	arraydatum: the array object (mustn't be NULL)
+ *	nSubscripts: number of subscripts supplied
+ *	indx[]: the subscript values
+ *	arraytyplen: pg_type.typlen for the array type
+ *	elmlen: pg_type.typlen for the array's element type
+ *	elmbyval: pg_type.typbyval for the array's element type
+ *	elmalign: pg_type.typalign for the array's element type
+ *
+ * Outputs:
+ *	The return value is the element Datum.
+ *	*isNull is set to indicate whether the element is NULL.
+ */
+Datum
+array_get_element(Datum arraydatum,
+				  int nSubscripts,
+				  int *indx,
+				  int arraytyplen,
+				  int elmlen,
+				  bool elmbyval,
+				  char elmalign,
+				  bool *isNull)
+{
+	int			i,
+				ndim,
+			   *dim,
+			   *lb,
+				offset,
+				fixedDim[1],
+				fixedLb[1];
+	char	   *arraydataptr,
+			   *retptr;
+	bits8	   *arraynullsptr;
+
+	if (arraytyplen > 0)
+	{
+		/*
+		 * fixed-length arrays -- these are assumed to be 1-d, 0-based
+		 */
+		ndim = 1;
+		fixedDim[0] = arraytyplen / elmlen;
+		fixedLb[0] = 0;
+		dim = fixedDim;
+		lb = fixedLb;
+		arraydataptr = (char *) DatumGetPointer(arraydatum);
+		arraynullsptr = NULL;
+	}
+	else if (VARATT_IS_EXTERNAL_EXPANDED(DatumGetPointer(arraydatum)))
+	{
+		/* expanded array: let's do this in a separate function */
+		return array_get_element_expanded(arraydatum,
+										  nSubscripts,
+										  indx,
+										  arraytyplen,
+										  elmlen,
+										  elmbyval,
+										  elmalign,
+										  isNull);
+	}
+	else
+	{
+		/* detoast array if necessary, producing normal varlena input */
+		ArrayType  *array = DatumGetArrayTypeP(arraydatum);
+
+		ndim = ARR_NDIM(array);
+		dim = ARR_DIMS(array);
+		lb = ARR_LBOUND(array);
+		arraydataptr = ARR_DATA_PTR(array);
+		arraynullsptr = ARR_NULLBITMAP(array);
+	}
+
+	/*
+	 * Return NULL for invalid subscript
+	 */
+	if (ndim != nSubscripts || ndim <= 0 || ndim > MAXDIM)
+	{
+		*isNull = true;
+		return (Datum) 0;
+	}
+	for (i = 0; i < ndim; i++)
+	{
+		if (indx[i] < lb[i] || indx[i] >= (dim[i] + lb[i]))
+		{
+			*isNull = true;
+			return (Datum) 0;
+		}
+	}
+
+	/*
+	 * Calculate the element number
+	 */
+	offset = ArrayGetOffset(nSubscripts, dim, lb, indx);
+
+	/*
+	 * Check for NULL array element
+	 */
+	if (array_get_isnull(arraynullsptr, offset))
+	{
+		*isNull = true;
+		return (Datum) 0;
+	}
+
+	/*
+	 * OK, get the element
+	 */
+	*isNull = false;
+	retptr = array_seek(arraydataptr, 0, arraynullsptr, offset,
+						elmlen, elmbyval, elmalign);
+	return ArrayCast(retptr, elmbyval, elmlen);
+}
+
+/*
+ * Implementation of array_get_element() for an expanded array
+ */
+static Datum
+array_get_element_expanded(Datum arraydatum,
+						   int nSubscripts, int *indx,
+						   int arraytyplen,
+						   int elmlen, bool elmbyval, char elmalign,
+						   bool *isNull)
+{
+	ExpandedArrayHeader *eah;
+	int			i,
+				ndim,
+			   *dim,
+			   *lb,
+				offset;
+	Datum	   *dvalues;
+	bool	   *dnulls;
+
+	eah = (ExpandedArrayHeader *) DatumGetEOHP(arraydatum);
+	Assert(eah->ea_magic == EA_MAGIC);
+
+	/* sanity-check caller's info against object */
+	Assert(arraytyplen == -1);
+	Assert(elmlen == eah->typlen);
+	Assert(elmbyval == eah->typbyval);
+	Assert(elmalign == eah->typalign);
+
+	ndim = eah->ndims;
+	dim = eah->dims;
+	lb = eah->lbound;
+
+	/*
+	 * Return NULL for invalid subscript
+	 */
+	if (ndim != nSubscripts || ndim <= 0 || ndim > MAXDIM)
+	{
+		*isNull = true;
+		return (Datum) 0;
+	}
+	for (i = 0; i < ndim; i++)
+	{
+		if (indx[i] < lb[i] || indx[i] >= (dim[i] + lb[i]))
+		{
+			*isNull = true;
+			return (Datum) 0;
+		}
+	}
+
+	/*
+	 * Calculate the element number
+	 */
+	offset = ArrayGetOffset(nSubscripts, dim, lb, indx);
+
+	/*
+	 * Deconstruct array if we didn't already.  Note that we apply this even
+	 * if the input is nominally read-only: it should be safe enough.
+	 */
+	deconstruct_expanded_array(eah);
+
+	dvalues = eah->dvalues;
+	dnulls = eah->dnulls;
+
+	/*
+	 * Check for NULL array element
+	 */
+	if (dnulls && dnulls[offset])
+	{
+		*isNull = true;
+		return (Datum) 0;
+	}
+
+	/*
+	 * OK, get the element.  It's OK to return a pass-by-ref value as a
+	 * pointer into the expanded array, for the same reason that regular
+	 * array_get_element can return a pointer into flat arrays: the value is
+	 * assumed not to change for as long as the Datum reference can exist.
+	 */
+	*isNull = false;
+	return dvalues[offset];
+}
+
+/*
+ * array_get_slice :
+ *		   This routine takes an array and a range of indices (upperIndx and
+ *		   lowerIndx), creates a new array structure for the referred elements
+ *		   and returns a pointer to it.
+ *
+ * This handles both ordinary varlena arrays and fixed-length arrays.
+ *
+ * Inputs:
+ *	arraydatum: the array object (mustn't be NULL)
+ *	nSubscripts: number of subscripts supplied (must be same for upper/lower)
+ *	upperIndx[]: the upper subscript values
+ *	lowerIndx[]: the lower subscript values
+ *	upperProvided[]: true for provided upper subscript values
+ *	lowerProvided[]: true for provided lower subscript values
+ *	arraytyplen: pg_type.typlen for the array type
+ *	elmlen: pg_type.typlen for the array's element type
+ *	elmbyval: pg_type.typbyval for the array's element type
+ *	elmalign: pg_type.typalign for the array's element type
+ *
+ * Outputs:
+ *	The return value is the new array Datum (it's never NULL)
+ *
+ * Omitted upper and lower subscript values are replaced by the corresponding
+ * array bound.
+ *
+ * NOTE: we assume it is OK to scribble on the provided subscript arrays
+ * lowerIndx[] and upperIndx[]; also, these arrays must be of size MAXDIM
+ * even when nSubscripts is less.  These are generally just temporaries.
+ */
+Datum
+array_get_slice(Datum arraydatum,
+				int nSubscripts,
+				int *upperIndx,
+				int *lowerIndx,
+				bool *upperProvided,
+				bool *lowerProvided,
+				int arraytyplen,
+				int elmlen,
+				bool elmbyval,
+				char elmalign)
+{
+	ArrayType  *array;
+	ArrayType  *newarray;
+	int			i,
+				ndim,
+			   *dim,
+			   *lb,
+			   *newlb;
+	int			fixedDim[1],
+				fixedLb[1];
+	Oid			elemtype;
+	char	   *arraydataptr;
+	bits8	   *arraynullsptr;
+	int32		dataoffset;
+	int			bytes,
+				span[MAXDIM];
+
+	if (arraytyplen > 0)
+	{
+		/*
+		 * fixed-length arrays -- currently, cannot slice these because parser
+		 * labels output as being of the fixed-length array type! Code below
+		 * shows how we could support it if the parser were changed to label
+		 * output as a suitable varlena array type.
+		 */
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("slices of fixed-length arrays not implemented")));
+
+		/*
+		 * fixed-length arrays -- these are assumed to be 1-d, 0-based
+		 *
+		 * XXX where would we get the correct ELEMTYPE from?
+		 */
+		ndim = 1;
+		fixedDim[0] = arraytyplen / elmlen;
+		fixedLb[0] = 0;
+		dim = fixedDim;
+		lb = fixedLb;
+		elemtype = InvalidOid;	/* XXX */
+		arraydataptr = (char *) DatumGetPointer(arraydatum);
+		arraynullsptr = NULL;
+	}
+	else
+	{
+		/* detoast input array if necessary */
+		array = DatumGetArrayTypeP(arraydatum);
+
+		ndim = ARR_NDIM(array);
+		dim = ARR_DIMS(array);
+		lb = ARR_LBOUND(array);
+		elemtype = ARR_ELEMTYPE(array);
+		arraydataptr = ARR_DATA_PTR(array);
+		arraynullsptr = ARR_NULLBITMAP(array);
+	}
+
+	/*
+	 * Check provided subscripts.  A slice exceeding the current array limits
+	 * is silently truncated to the array limits.  If we end up with an empty
+	 * slice, return an empty array.
+	 */
+	if (ndim < nSubscripts || ndim <= 0 || ndim > MAXDIM)
+		return PointerGetDatum(construct_empty_array(elemtype));
+
+	for (i = 0; i < nSubscripts; i++)
+	{
+		if (!lowerProvided[i] || lowerIndx[i] < lb[i])
+			lowerIndx[i] = lb[i];
+		if (!upperProvided[i] || upperIndx[i] >= (dim[i] + lb[i]))
+			upperIndx[i] = dim[i] + lb[i] - 1;
+		if (lowerIndx[i] > upperIndx[i])
+			return PointerGetDatum(construct_empty_array(elemtype));
+	}
+	/* fill any missing subscript positions with full array range */
+	for (; i < ndim; i++)
+	{
+		lowerIndx[i] = lb[i];
+		upperIndx[i] = dim[i] + lb[i] - 1;
+		if (lowerIndx[i] > upperIndx[i])
+			return PointerGetDatum(construct_empty_array(elemtype));
+	}
+
+	mda_get_range(ndim, span, lowerIndx, upperIndx);
+
+	bytes = array_slice_size(arraydataptr, arraynullsptr,
+							 ndim, dim, lb,
+							 lowerIndx, upperIndx,
+							 elmlen, elmbyval, elmalign);
+
+	/*
+	 * Currently, we put a null bitmap in the result if the source has one;
+	 * could be smarter ...
+	 */
+	if (arraynullsptr)
+	{
+		dataoffset = ARR_OVERHEAD_WITHNULLS(ndim, ArrayGetNItems(ndim, span));
+		bytes += dataoffset;
+	}
+	else
+	{
+		dataoffset = 0;			/* marker for no null bitmap */
+		bytes += ARR_OVERHEAD_NONULLS(ndim);
+	}
+
+	newarray = (ArrayType *) palloc0(bytes);
+	SET_VARSIZE(newarray, bytes);
+	newarray->ndim = ndim;
+	newarray->dataoffset = dataoffset;
+	newarray->elemtype = elemtype;
+	memcpy(ARR_DIMS(newarray), span, ndim * sizeof(int));
+
+	/*
+	 * Lower bounds of the new array are set to 1.  Formerly (before 7.3) we
+	 * copied the given lowerIndx values ... but that seems confusing.
+	 */
+	newlb = ARR_LBOUND(newarray);
+	for (i = 0; i < ndim; i++)
+		newlb[i] = 1;
+
+	array_extract_slice(newarray,
+						ndim, dim, lb,
+						arraydataptr, arraynullsptr,
+						lowerIndx, upperIndx,
+						elmlen, elmbyval, elmalign);
+
+	return PointerGetDatum(newarray);
+}
+
+/*
+ * array_set_element :
+ *		  This routine sets the value of one array element (specified by
+ *		  a subscript array) to a new value specified by "dataValue".
+ *
+ * This handles both ordinary varlena arrays and fixed-length arrays.
+ *
+ * Inputs:
+ *	arraydatum: the initial array object (mustn't be NULL)
+ *	nSubscripts: number of subscripts supplied
+ *	indx[]: the subscript values
+ *	dataValue: the datum to be inserted at the given position
+ *	isNull: whether dataValue is NULL
+ *	arraytyplen: pg_type.typlen for the array type
+ *	elmlen: pg_type.typlen for the array's element type
+ *	elmbyval: pg_type.typbyval for the array's element type
+ *	elmalign: pg_type.typalign for the array's element type
+ *
+ * Result:
+ *		  A new array is returned, just like the old except for the one
+ *		  modified entry.  The original array object is not changed,
+ *		  unless what is passed is a read-write reference to an expanded
+ *		  array object; in that case the expanded array is updated in-place.
+ *
+ * For one-dimensional arrays only, we allow the array to be extended
+ * by assigning to a position outside the existing subscript range; any
+ * positions between the existing elements and the new one are set to NULLs.
+ * (XXX TODO: allow a corresponding behavior for multidimensional arrays)
+ *
+ * NOTE: For assignments, we throw an error for invalid subscripts etc,
+ * rather than returning a NULL as the fetch operations do.
+ */
+Datum
+array_set_element(Datum arraydatum,
+				  int nSubscripts,
+				  int *indx,
+				  Datum dataValue,
+				  bool isNull,
+				  int arraytyplen,
+				  int elmlen,
+				  bool elmbyval,
+				  char elmalign)
+{
+	ArrayType  *array;
+	ArrayType  *newarray;
+	int			i,
+				ndim,
+				dim[MAXDIM],
+				lb[MAXDIM],
+				offset;
+	char	   *elt_ptr;
+	bool		newhasnulls;
+	bits8	   *oldnullbitmap;
+	int			oldnitems,
+				newnitems,
+				olddatasize,
+				newsize,
+				olditemlen,
+				newitemlen,
+				overheadlen,
+				oldoverheadlen,
+				addedbefore,
+				addedafter,
+				lenbefore,
+				lenafter;
+
+	if (arraytyplen > 0)
+	{
+		/*
+		 * fixed-length arrays -- these are assumed to be 1-d, 0-based. We
+		 * cannot extend them, either.
+		 */
+		char	   *resultarray;
+
+		if (nSubscripts != 1)
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("wrong number of array subscripts")));
+
+		if (indx[0] < 0 || indx[0] >= arraytyplen / elmlen)
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("array subscript out of range")));
+
+		if (isNull)
+			ereport(ERROR,
+					(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+					 errmsg("cannot assign null value to an element of a fixed-length array")));
+
+		resultarray = (char *) palloc(arraytyplen);
+		memcpy(resultarray, DatumGetPointer(arraydatum), arraytyplen);
+		elt_ptr = (char *) resultarray + indx[0] * elmlen;
+		ArrayCastAndSet(dataValue, elmlen, elmbyval, elmalign, elt_ptr);
+		return PointerGetDatum(resultarray);
+	}
+
+	if (nSubscripts <= 0 || nSubscripts > MAXDIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("wrong number of array subscripts")));
+
+	/* make sure item to be inserted is not toasted */
+	if (elmlen == -1 && !isNull)
+		dataValue = PointerGetDatum(PG_DETOAST_DATUM(dataValue));
+
+	if (VARATT_IS_EXTERNAL_EXPANDED(DatumGetPointer(arraydatum)))
+	{
+		/* expanded array: let's do this in a separate function */
+		return array_set_element_expanded(arraydatum,
+										  nSubscripts,
+										  indx,
+										  dataValue,
+										  isNull,
+										  arraytyplen,
+										  elmlen,
+										  elmbyval,
+										  elmalign);
+	}
+
+	/* detoast input array if necessary */
+	array = DatumGetArrayTypeP(arraydatum);
+
+	ndim = ARR_NDIM(array);
+
+	/*
+	 * if number of dims is zero, i.e. an empty array, create an array with
+	 * nSubscripts dimensions, and set the lower bounds to the supplied
+	 * subscripts
+	 */
+	if (ndim == 0)
+	{
+		Oid			elmtype = ARR_ELEMTYPE(array);
+
+		for (i = 0; i < nSubscripts; i++)
+		{
+			dim[i] = 1;
+			lb[i] = indx[i];
+		}
+
+		return PointerGetDatum(construct_md_array(&dataValue, &isNull,
+												  nSubscripts, dim, lb,
+												  elmtype,
+												  elmlen, elmbyval, elmalign));
+	}
+
+	if (ndim != nSubscripts)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("wrong number of array subscripts")));
+
+	/* copy dim/lb since we may modify them */
+	memcpy(dim, ARR_DIMS(array), ndim * sizeof(int));
+	memcpy(lb, ARR_LBOUND(array), ndim * sizeof(int));
+
+	newhasnulls = (ARR_HASNULL(array) || isNull);
+	addedbefore = addedafter = 0;
+
+	/*
+	 * Check subscripts
+	 */
+	if (ndim == 1)
+	{
+		if (indx[0] < lb[0])
+		{
+			addedbefore = lb[0] - indx[0];
+			dim[0] += addedbefore;
+			lb[0] = indx[0];
+			if (addedbefore > 1)
+				newhasnulls = true; /* will insert nulls */
+		}
+		if (indx[0] >= (dim[0] + lb[0]))
+		{
+			addedafter = indx[0] - (dim[0] + lb[0]) + 1;
+			dim[0] += addedafter;
+			if (addedafter > 1)
+				newhasnulls = true; /* will insert nulls */
+		}
+	}
+	else
+	{
+		/*
+		 * XXX currently we do not support extending multi-dimensional arrays
+		 * during assignment
+		 */
+		for (i = 0; i < ndim; i++)
+		{
+			if (indx[i] < lb[i] ||
+				indx[i] >= (dim[i] + lb[i]))
+				ereport(ERROR,
+						(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+						 errmsg("array subscript out of range")));
+		}
+	}
+
+	/* This checks for overflow of the array dimensions */
+	newnitems = ArrayGetNItems(ndim, dim);
+	ArrayCheckBounds(ndim, dim, lb);
+
+	/*
+	 * Compute sizes of items and areas to copy
+	 */
+	if (newhasnulls)
+		overheadlen = ARR_OVERHEAD_WITHNULLS(ndim, newnitems);
+	else
+		overheadlen = ARR_OVERHEAD_NONULLS(ndim);
+	oldnitems = ArrayGetNItems(ndim, ARR_DIMS(array));
+	oldnullbitmap = ARR_NULLBITMAP(array);
+	oldoverheadlen = ARR_DATA_OFFSET(array);
+	olddatasize = ARR_SIZE(array) - oldoverheadlen;
+	if (addedbefore)
+	{
+		offset = 0;
+		lenbefore = 0;
+		olditemlen = 0;
+		lenafter = olddatasize;
+	}
+	else if (addedafter)
+	{
+		offset = oldnitems;
+		lenbefore = olddatasize;
+		olditemlen = 0;
+		lenafter = 0;
+	}
+	else
+	{
+		offset = ArrayGetOffset(nSubscripts, dim, lb, indx);
+		elt_ptr = array_seek(ARR_DATA_PTR(array), 0, oldnullbitmap, offset,
+							 elmlen, elmbyval, elmalign);
+		lenbefore = (int) (elt_ptr - ARR_DATA_PTR(array));
+		if (array_get_isnull(oldnullbitmap, offset))
+			olditemlen = 0;
+		else
+		{
+			olditemlen = att_addlength_pointer(0, elmlen, elt_ptr);
+			olditemlen = att_align_nominal(olditemlen, elmalign);
+		}
+		lenafter = (int) (olddatasize - lenbefore - olditemlen);
+	}
+
+	if (isNull)
+		newitemlen = 0;
+	else
+	{
+		newitemlen = att_addlength_datum(0, elmlen, dataValue);
+		newitemlen = att_align_nominal(newitemlen, elmalign);
+	}
+
+	newsize = overheadlen + lenbefore + newitemlen + lenafter;
+
+	/*
+	 * OK, create the new array and fill in header/dimensions
+	 */
+	newarray = (ArrayType *) palloc0(newsize);
+	SET_VARSIZE(newarray, newsize);
+	newarray->ndim = ndim;
+	newarray->dataoffset = newhasnulls ? overheadlen : 0;
+	newarray->elemtype = ARR_ELEMTYPE(array);
+	memcpy(ARR_DIMS(newarray), dim, ndim * sizeof(int));
+	memcpy(ARR_LBOUND(newarray), lb, ndim * sizeof(int));
+
+	/*
+	 * Fill in data
+	 */
+	memcpy((char *) newarray + overheadlen,
+		   (char *) array + oldoverheadlen,
+		   lenbefore);
+	if (!isNull)
+		ArrayCastAndSet(dataValue, elmlen, elmbyval, elmalign,
+						(char *) newarray + overheadlen + lenbefore);
+	memcpy((char *) newarray + overheadlen + lenbefore + newitemlen,
+		   (char *) array + oldoverheadlen + lenbefore + olditemlen,
+		   lenafter);
+
+	/*
+	 * Fill in nulls bitmap if needed
+	 *
+	 * Note: it's possible we just replaced the last NULL with a non-NULL, and
+	 * could get rid of the bitmap.  Seems not worth testing for though.
+	 */
+	if (newhasnulls)
+	{
+		bits8	   *newnullbitmap = ARR_NULLBITMAP(newarray);
+
+		/* Zero the bitmap to take care of marking inserted positions null */
+		MemSet(newnullbitmap, 0, (newnitems + 7) / 8);
+		/* Fix the inserted value */
+		if (addedafter)
+			array_set_isnull(newnullbitmap, newnitems - 1, isNull);
+		else
+			array_set_isnull(newnullbitmap, offset, isNull);
+		/* Fix the copied range(s) */
+		if (addedbefore)
+			array_bitmap_copy(newnullbitmap, addedbefore,
+							  oldnullbitmap, 0,
+							  oldnitems);
+		else
+		{
+			array_bitmap_copy(newnullbitmap, 0,
+							  oldnullbitmap, 0,
+							  offset);
+			if (addedafter == 0)
+				array_bitmap_copy(newnullbitmap, offset + 1,
+								  oldnullbitmap, offset + 1,
+								  oldnitems - offset - 1);
+		}
+	}
+
+	return PointerGetDatum(newarray);
+}
+
+/*
+ * Implementation of array_set_element() for an expanded array
+ *
+ * Note: as with any operation on a read/write expanded object, we must
+ * take pains not to leave the object in a corrupt state if we fail partway
+ * through.
+ */
+static Datum
+array_set_element_expanded(Datum arraydatum,
+						   int nSubscripts, int *indx,
+						   Datum dataValue, bool isNull,
+						   int arraytyplen,
+						   int elmlen, bool elmbyval, char elmalign)
+{
+	ExpandedArrayHeader *eah;
+	Datum	   *dvalues;
+	bool	   *dnulls;
+	int			i,
+				ndim,
+				dim[MAXDIM],
+				lb[MAXDIM],
+				offset;
+	bool		dimschanged,
+				newhasnulls;
+	int			addedbefore,
+				addedafter;
+	char	   *oldValue;
+
+	/* Convert to R/W object if not so already */
+	eah = DatumGetExpandedArray(arraydatum);
+
+	/* Sanity-check caller's info against object; we don't use it otherwise */
+	Assert(arraytyplen == -1);
+	Assert(elmlen == eah->typlen);
+	Assert(elmbyval == eah->typbyval);
+	Assert(elmalign == eah->typalign);
+
+	/*
+	 * Copy dimension info into local storage.  This allows us to modify the
+	 * dimensions if needed, while not messing up the expanded value if we
+	 * fail partway through.
+	 */
+	ndim = eah->ndims;
+	Assert(ndim >= 0 && ndim <= MAXDIM);
+	memcpy(dim, eah->dims, ndim * sizeof(int));
+	memcpy(lb, eah->lbound, ndim * sizeof(int));
+	dimschanged = false;
+
+	/*
+	 * if number of dims is zero, i.e. an empty array, create an array with
+	 * nSubscripts dimensions, and set the lower bounds to the supplied
+	 * subscripts.
+	 */
+	if (ndim == 0)
+	{
+		/*
+		 * Allocate adequate space for new dimension info.  This is harmless
+		 * if we fail later.
+		 */
+		Assert(nSubscripts > 0 && nSubscripts <= MAXDIM);
+		eah->dims = (int *) MemoryContextAllocZero(eah->hdr.eoh_context,
+												   nSubscripts * sizeof(int));
+		eah->lbound = (int *) MemoryContextAllocZero(eah->hdr.eoh_context,
+													 nSubscripts * sizeof(int));
+
+		/* Update local copies of dimension info */
+		ndim = nSubscripts;
+		for (i = 0; i < nSubscripts; i++)
+		{
+			dim[i] = 0;
+			lb[i] = indx[i];
+		}
+		dimschanged = true;
+	}
+	else if (ndim != nSubscripts)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("wrong number of array subscripts")));
+
+	/*
+	 * Deconstruct array if we didn't already.  (Someday maybe add a special
+	 * case path for fixed-length, no-nulls cases, where we can overwrite an
+	 * element in place without ever deconstructing.  But today is not that
+	 * day.)
+	 */
+	deconstruct_expanded_array(eah);
+
+	/*
+	 * Copy new element into array's context, if needed (we assume it's
+	 * already detoasted, so no junk should be created).  Doing this before
+	 * we've made any significant changes ensures that our behavior is sane
+	 * even when the source is a reference to some element of this same array.
+	 * If we fail further down, this memory is leaked, but that's reasonably
+	 * harmless.
+	 */
+	if (!eah->typbyval && !isNull)
+	{
+		MemoryContext oldcxt = MemoryContextSwitchTo(eah->hdr.eoh_context);
+
+		dataValue = datumCopy(dataValue, false, eah->typlen);
+		MemoryContextSwitchTo(oldcxt);
+	}
+
+	dvalues = eah->dvalues;
+	dnulls = eah->dnulls;
+
+	newhasnulls = ((dnulls != NULL) || isNull);
+	addedbefore = addedafter = 0;
+
+	/*
+	 * Check subscripts (this logic matches original array_set_element)
+	 */
+	if (ndim == 1)
+	{
+		if (indx[0] < lb[0])
+		{
+			addedbefore = lb[0] - indx[0];
+			dim[0] += addedbefore;
+			lb[0] = indx[0];
+			dimschanged = true;
+			if (addedbefore > 1)
+				newhasnulls = true; /* will insert nulls */
+		}
+		if (indx[0] >= (dim[0] + lb[0]))
+		{
+			addedafter = indx[0] - (dim[0] + lb[0]) + 1;
+			dim[0] += addedafter;
+			dimschanged = true;
+			if (addedafter > 1)
+				newhasnulls = true; /* will insert nulls */
+		}
+	}
+	else
+	{
+		/*
+		 * XXX currently we do not support extending multi-dimensional arrays
+		 * during assignment
+		 */
+		for (i = 0; i < ndim; i++)
+		{
+			if (indx[i] < lb[i] ||
+				indx[i] >= (dim[i] + lb[i]))
+				ereport(ERROR,
+						(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+						 errmsg("array subscript out of range")));
+		}
+	}
+
+	/* Check for overflow of the array dimensions */
+	if (dimschanged)
+	{
+		(void) ArrayGetNItems(ndim, dim);
+		ArrayCheckBounds(ndim, dim, lb);
+	}
+
+	/* Now we can calculate linear offset of target item in array */
+	offset = ArrayGetOffset(nSubscripts, dim, lb, indx);
+
+	/* Physically enlarge existing dvalues/dnulls arrays if needed */
+	if (dim[0] > eah->dvalueslen)
+	{
+		/* We want some extra space if we're enlarging */
+		int			newlen = dim[0] + dim[0] / 8;
+
+		newlen = Max(newlen, dim[0]);	/* integer overflow guard */
+		eah->dvalues = dvalues = (Datum *)
+			repalloc(dvalues, newlen * sizeof(Datum));
+		if (dnulls)
+			eah->dnulls = dnulls = (bool *)
+				repalloc(dnulls, newlen * sizeof(bool));
+		eah->dvalueslen = newlen;
+	}
+
+	/*
+	 * If we need a nulls bitmap and don't already have one, create it, being
+	 * sure to mark all existing entries as not null.
+	 */
+	if (newhasnulls && dnulls == NULL)
+		eah->dnulls = dnulls = (bool *)
+			MemoryContextAllocZero(eah->hdr.eoh_context,
+								   eah->dvalueslen * sizeof(bool));
+
+	/*
+	 * We now have all the needed space allocated, so we're ready to make
+	 * irreversible changes.  Be very wary of allowing failure below here.
+	 */
+
+	/* Flattened value will no longer represent array accurately */
+	eah->fvalue = NULL;
+	/* And we don't know the flattened size either */
+	eah->flat_size = 0;
+
+	/* Update dimensionality info if needed */
+	if (dimschanged)
+	{
+		eah->ndims = ndim;
+		memcpy(eah->dims, dim, ndim * sizeof(int));
+		memcpy(eah->lbound, lb, ndim * sizeof(int));
+	}
+
+	/* Reposition items if needed, and fill addedbefore items with nulls */
+	if (addedbefore > 0)
+	{
+		memmove(dvalues + addedbefore, dvalues, eah->nelems * sizeof(Datum));
+		for (i = 0; i < addedbefore; i++)
+			dvalues[i] = (Datum) 0;
+		if (dnulls)
+		{
+			memmove(dnulls + addedbefore, dnulls, eah->nelems * sizeof(bool));
+			for (i = 0; i < addedbefore; i++)
+				dnulls[i] = true;
+		}
+		eah->nelems += addedbefore;
+	}
+
+	/* fill addedafter items with nulls */
+	if (addedafter > 0)
+	{
+		for (i = 0; i < addedafter; i++)
+			dvalues[eah->nelems + i] = (Datum) 0;
+		if (dnulls)
+		{
+			for (i = 0; i < addedafter; i++)
+				dnulls[eah->nelems + i] = true;
+		}
+		eah->nelems += addedafter;
+	}
+
+	/* Grab old element value for pfree'ing, if needed. */
+	if (!eah->typbyval && (dnulls == NULL || !dnulls[offset]))
+		oldValue = (char *) DatumGetPointer(dvalues[offset]);
+	else
+		oldValue = NULL;
+
+	/* And finally we can insert the new element. */
+	dvalues[offset] = dataValue;
+	if (dnulls)
+		dnulls[offset] = isNull;
+
+	/*
+	 * Free old element if needed; this keeps repeated element replacements
+	 * from bloating the array's storage.  If the pfree somehow fails, it
+	 * won't corrupt the array.
+	 */
+	if (oldValue)
+	{
+		/* Don't try to pfree a part of the original flat array */
+		if (oldValue < eah->fstartptr || oldValue >= eah->fendptr)
+			pfree(oldValue);
+	}
+
+	/* Done, return standard TOAST pointer for object */
+	return EOHPGetRWDatum(&eah->hdr);
+}
+
+/*
+ * array_set_slice :
+ *		  This routine sets the value of a range of array locations (specified
+ *		  by upper and lower subscript values) to new values passed as
+ *		  another array.
+ *
+ * This handles both ordinary varlena arrays and fixed-length arrays.
+ *
+ * Inputs:
+ *	arraydatum: the initial array object (mustn't be NULL)
+ *	nSubscripts: number of subscripts supplied (must be same for upper/lower)
+ *	upperIndx[]: the upper subscript values
+ *	lowerIndx[]: the lower subscript values
+ *	upperProvided[]: true for provided upper subscript values
+ *	lowerProvided[]: true for provided lower subscript values
+ *	srcArrayDatum: the source for the inserted values
+ *	isNull: indicates whether srcArrayDatum is NULL
+ *	arraytyplen: pg_type.typlen for the array type
+ *	elmlen: pg_type.typlen for the array's element type
+ *	elmbyval: pg_type.typbyval for the array's element type
+ *	elmalign: pg_type.typalign for the array's element type
+ *
+ * Result:
+ *		  A new array is returned, just like the old except for the
+ *		  modified range.  The original array object is not changed.
+ *
+ * Omitted upper and lower subscript values are replaced by the corresponding
+ * array bound.
+ *
+ * For one-dimensional arrays only, we allow the array to be extended
+ * by assigning to positions outside the existing subscript range; any
+ * positions between the existing elements and the new ones are set to NULLs.
+ * (XXX TODO: allow a corresponding behavior for multidimensional arrays)
+ *
+ * NOTE: we assume it is OK to scribble on the provided index arrays
+ * lowerIndx[] and upperIndx[]; also, these arrays must be of size MAXDIM
+ * even when nSubscripts is less.  These are generally just temporaries.
+ *
+ * NOTE: For assignments, we throw an error for silly subscripts etc,
+ * rather than returning a NULL or empty array as the fetch operations do.
+ */
+Datum
+array_set_slice(Datum arraydatum,
+				int nSubscripts,
+				int *upperIndx,
+				int *lowerIndx,
+				bool *upperProvided,
+				bool *lowerProvided,
+				Datum srcArrayDatum,
+				bool isNull,
+				int arraytyplen,
+				int elmlen,
+				bool elmbyval,
+				char elmalign)
+{
+	ArrayType  *array;
+	ArrayType  *srcArray;
+	ArrayType  *newarray;
+	int			i,
+				ndim,
+				dim[MAXDIM],
+				lb[MAXDIM],
+				span[MAXDIM];
+	bool		newhasnulls;
+	int			nitems,
+				nsrcitems,
+				olddatasize,
+				newsize,
+				olditemsize,
+				newitemsize,
+				overheadlen,
+				oldoverheadlen,
+				addedbefore,
+				addedafter,
+				lenbefore,
+				lenafter,
+				itemsbefore,
+				itemsafter,
+				nolditems;
+
+	/* Currently, assignment from a NULL source array is a no-op */
+	if (isNull)
+		return arraydatum;
+
+	if (arraytyplen > 0)
+	{
+		/*
+		 * fixed-length arrays -- not got round to doing this...
+		 */
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("updates on slices of fixed-length arrays not implemented")));
+	}
+
+	/* detoast arrays if necessary */
+	array = DatumGetArrayTypeP(arraydatum);
+	srcArray = DatumGetArrayTypeP(srcArrayDatum);
+
+	/* note: we assume srcArray contains no toasted elements */
+
+	ndim = ARR_NDIM(array);
+
+	/*
+	 * if number of dims is zero, i.e. an empty array, create an array with
+	 * nSubscripts dimensions, and set the upper and lower bounds to the
+	 * supplied subscripts
+	 */
+	if (ndim == 0)
+	{
+		Datum	   *dvalues;
+		bool	   *dnulls;
+		int			nelems;
+		Oid			elmtype = ARR_ELEMTYPE(array);
+
+		deconstruct_array(srcArray, elmtype, elmlen, elmbyval, elmalign,
+						  &dvalues, &dnulls, &nelems);
+
+		for (i = 0; i < nSubscripts; i++)
+		{
+			if (!upperProvided[i] || !lowerProvided[i])
+				ereport(ERROR,
+						(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+						 errmsg("array slice subscript must provide both boundaries"),
+						 errdetail("When assigning to a slice of an empty array value,"
+								   " slice boundaries must be fully specified.")));
+
+			dim[i] = 1 + upperIndx[i] - lowerIndx[i];
+			lb[i] = lowerIndx[i];
+		}
+
+		/* complain if too few source items; we ignore extras, however */
+		if (nelems < ArrayGetNItems(nSubscripts, dim))
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("source array too small")));
+
+		return PointerGetDatum(construct_md_array(dvalues, dnulls, nSubscripts,
+												  dim, lb, elmtype,
+												  elmlen, elmbyval, elmalign));
+	}
+
+	if (ndim < nSubscripts || ndim <= 0 || ndim > MAXDIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("wrong number of array subscripts")));
+
+	/* copy dim/lb since we may modify them */
+	memcpy(dim, ARR_DIMS(array), ndim * sizeof(int));
+	memcpy(lb, ARR_LBOUND(array), ndim * sizeof(int));
+
+	newhasnulls = (ARR_HASNULL(array) || ARR_HASNULL(srcArray));
+	addedbefore = addedafter = 0;
+
+	/*
+	 * Check subscripts
+	 */
+	if (ndim == 1)
+	{
+		Assert(nSubscripts == 1);
+		if (!lowerProvided[0])
+			lowerIndx[0] = lb[0];
+		if (!upperProvided[0])
+			upperIndx[0] = dim[0] + lb[0] - 1;
+		if (lowerIndx[0] > upperIndx[0])
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("upper bound cannot be less than lower bound")));
+		if (lowerIndx[0] < lb[0])
+		{
+			if (upperIndx[0] < lb[0] - 1)
+				newhasnulls = true; /* will insert nulls */
+			addedbefore = lb[0] - lowerIndx[0];
+			dim[0] += addedbefore;
+			lb[0] = lowerIndx[0];
+		}
+		if (upperIndx[0] >= (dim[0] + lb[0]))
+		{
+			if (lowerIndx[0] > (dim[0] + lb[0]))
+				newhasnulls = true; /* will insert nulls */
+			addedafter = upperIndx[0] - (dim[0] + lb[0]) + 1;
+			dim[0] += addedafter;
+		}
+	}
+	else
+	{
+		/*
+		 * XXX currently we do not support extending multi-dimensional arrays
+		 * during assignment
+		 */
+		for (i = 0; i < nSubscripts; i++)
+		{
+			if (!lowerProvided[i])
+				lowerIndx[i] = lb[i];
+			if (!upperProvided[i])
+				upperIndx[i] = dim[i] + lb[i] - 1;
+			if (lowerIndx[i] > upperIndx[i])
+				ereport(ERROR,
+						(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+						 errmsg("upper bound cannot be less than lower bound")));
+			if (lowerIndx[i] < lb[i] ||
+				upperIndx[i] >= (dim[i] + lb[i]))
+				ereport(ERROR,
+						(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+						 errmsg("array subscript out of range")));
+		}
+		/* fill any missing subscript positions with full array range */
+		for (; i < ndim; i++)
+		{
+			lowerIndx[i] = lb[i];
+			upperIndx[i] = dim[i] + lb[i] - 1;
+			if (lowerIndx[i] > upperIndx[i])
+				ereport(ERROR,
+						(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+						 errmsg("upper bound cannot be less than lower bound")));
+		}
+	}
+
+	/* Do this mainly to check for overflow */
+	nitems = ArrayGetNItems(ndim, dim);
+	ArrayCheckBounds(ndim, dim, lb);
+
+	/*
+	 * Make sure source array has enough entries.  Note we ignore the shape of
+	 * the source array and just read entries serially.
+	 */
+	mda_get_range(ndim, span, lowerIndx, upperIndx);
+	nsrcitems = ArrayGetNItems(ndim, span);
+	if (nsrcitems > ArrayGetNItems(ARR_NDIM(srcArray), ARR_DIMS(srcArray)))
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("source array too small")));
+
+	/*
+	 * Compute space occupied by new entries, space occupied by replaced
+	 * entries, and required space for new array.
+	 */
+	if (newhasnulls)
+		overheadlen = ARR_OVERHEAD_WITHNULLS(ndim, nitems);
+	else
+		overheadlen = ARR_OVERHEAD_NONULLS(ndim);
+	newitemsize = array_nelems_size(ARR_DATA_PTR(srcArray), 0,
+									ARR_NULLBITMAP(srcArray), nsrcitems,
+									elmlen, elmbyval, elmalign);
+	oldoverheadlen = ARR_DATA_OFFSET(array);
+	olddatasize = ARR_SIZE(array) - oldoverheadlen;
+	if (ndim > 1)
+	{
+		/*
+		 * here we do not need to cope with extension of the array; it would
+		 * be a lot more complicated if we had to do so...
+		 */
+		olditemsize = array_slice_size(ARR_DATA_PTR(array),
+									   ARR_NULLBITMAP(array),
+									   ndim, dim, lb,
+									   lowerIndx, upperIndx,
+									   elmlen, elmbyval, elmalign);
+		lenbefore = lenafter = 0;	/* keep compiler quiet */
+		itemsbefore = itemsafter = nolditems = 0;
+	}
+	else
+	{
+		/*
+		 * here we must allow for possibility of slice larger than orig array
+		 * and/or not adjacent to orig array subscripts
+		 */
+		int			oldlb = ARR_LBOUND(array)[0];
+		int			oldub = oldlb + ARR_DIMS(array)[0] - 1;
+		int			slicelb = Max(oldlb, lowerIndx[0]);
+		int			sliceub = Min(oldub, upperIndx[0]);
+		char	   *oldarraydata = ARR_DATA_PTR(array);
+		bits8	   *oldarraybitmap = ARR_NULLBITMAP(array);
+
+		/* count/size of old array entries that will go before the slice */
+		itemsbefore = Min(slicelb, oldub + 1) - oldlb;
+		lenbefore = array_nelems_size(oldarraydata, 0, oldarraybitmap,
+									  itemsbefore,
+									  elmlen, elmbyval, elmalign);
+		/* count/size of old array entries that will be replaced by slice */
+		if (slicelb > sliceub)
+		{
+			nolditems = 0;
+			olditemsize = 0;
+		}
+		else
+		{
+			nolditems = sliceub - slicelb + 1;
+			olditemsize = array_nelems_size(oldarraydata + lenbefore,
+											itemsbefore, oldarraybitmap,
+											nolditems,
+											elmlen, elmbyval, elmalign);
+		}
+		/* count/size of old array entries that will go after the slice */
+		itemsafter = oldub + 1 - Max(sliceub + 1, oldlb);
+		lenafter = olddatasize - lenbefore - olditemsize;
+	}
+
+	newsize = overheadlen + olddatasize - olditemsize + newitemsize;
+
+	newarray = (ArrayType *) palloc0(newsize);
+	SET_VARSIZE(newarray, newsize);
+	newarray->ndim = ndim;
+	newarray->dataoffset = newhasnulls ? overheadlen : 0;
+	newarray->elemtype = ARR_ELEMTYPE(array);
+	memcpy(ARR_DIMS(newarray), dim, ndim * sizeof(int));
+	memcpy(ARR_LBOUND(newarray), lb, ndim * sizeof(int));
+
+	if (ndim > 1)
+	{
+		/*
+		 * here we do not need to cope with extension of the array; it would
+		 * be a lot more complicated if we had to do so...
+		 */
+		array_insert_slice(newarray, array, srcArray,
+						   ndim, dim, lb,
+						   lowerIndx, upperIndx,
+						   elmlen, elmbyval, elmalign);
+	}
+	else
+	{
+		/* fill in data */
+		memcpy((char *) newarray + overheadlen,
+			   (char *) array + oldoverheadlen,
+			   lenbefore);
+		memcpy((char *) newarray + overheadlen + lenbefore,
+			   ARR_DATA_PTR(srcArray),
+			   newitemsize);
+		memcpy((char *) newarray + overheadlen + lenbefore + newitemsize,
+			   (char *) array + oldoverheadlen + lenbefore + olditemsize,
+			   lenafter);
+		/* fill in nulls bitmap if needed */
+		if (newhasnulls)
+		{
+			bits8	   *newnullbitmap = ARR_NULLBITMAP(newarray);
+			bits8	   *oldnullbitmap = ARR_NULLBITMAP(array);
+
+			/* Zero the bitmap to handle marking inserted positions null */
+			MemSet(newnullbitmap, 0, (nitems + 7) / 8);
+			array_bitmap_copy(newnullbitmap, addedbefore,
+							  oldnullbitmap, 0,
+							  itemsbefore);
+			array_bitmap_copy(newnullbitmap, lowerIndx[0] - lb[0],
+							  ARR_NULLBITMAP(srcArray), 0,
+							  nsrcitems);
+			array_bitmap_copy(newnullbitmap, addedbefore + itemsbefore + nolditems,
+							  oldnullbitmap, itemsbefore + nolditems,
+							  itemsafter);
+		}
+	}
+
+	return PointerGetDatum(newarray);
+}
+
+/*
+ * array_ref : backwards compatibility wrapper for array_get_element
+ *
+ * This only works for detoasted/flattened varlena arrays, since the array
+ * argument is declared as "ArrayType *".  However there's enough code like
+ * that to justify preserving this API.
+ */
+Datum
+array_ref(ArrayType *array, int nSubscripts, int *indx,
+		  int arraytyplen, int elmlen, bool elmbyval, char elmalign,
+		  bool *isNull)
+{
+	return array_get_element(PointerGetDatum(array), nSubscripts, indx,
+							 arraytyplen, elmlen, elmbyval, elmalign,
+							 isNull);
+}
+
+/*
+ * array_set : backwards compatibility wrapper for array_set_element
+ *
+ * This only works for detoasted/flattened varlena arrays, since the array
+ * argument and result are declared as "ArrayType *".  However there's enough
+ * code like that to justify preserving this API.
+ */
+ArrayType *
+array_set(ArrayType *array, int nSubscripts, int *indx,
+		  Datum dataValue, bool isNull,
+		  int arraytyplen, int elmlen, bool elmbyval, char elmalign)
+{
+	return DatumGetArrayTypeP(array_set_element(PointerGetDatum(array),
+												nSubscripts, indx,
+												dataValue, isNull,
+												arraytyplen,
+												elmlen, elmbyval, elmalign));
+}
+
+/*
+ * array_map()
+ *
+ * Map an array through an arbitrary expression.  Return a new array with
+ * the same dimensions and each source element transformed by the given,
+ * already-compiled expression.  Each source element is placed in the
+ * innermost_caseval/innermost_casenull fields of the ExprState.
+ *
+ * Parameters are:
+ * * arrayd: Datum representing array argument.
+ * * exprstate: ExprState representing the per-element transformation.
+ * * econtext: context for expression evaluation.
+ * * retType: OID of element type of output array.  This must be the same as,
+ *	 or binary-compatible with, the result type of the expression.  It might
+ *	 be different from the input array's element type.
+ * * amstate: workspace for array_map.  Must be zeroed by caller before
+ *	 first call, and not touched after that.
+ *
+ * It is legitimate to pass a freshly-zeroed ArrayMapState on each call,
+ * but better performance can be had if the state can be preserved across
+ * a series of calls.
+ *
+ * NB: caller must assure that input array is not NULL.  NULL elements in
+ * the array are OK however.
+ * NB: caller should be running in econtext's per-tuple memory context.
+ */
+Datum
+array_map(Datum arrayd,
+		  ExprState *exprstate, ExprContext *econtext,
+		  Oid retType, ArrayMapState *amstate)
+{
+	AnyArrayType *v = DatumGetAnyArrayP(arrayd);
+	ArrayType  *result;
+	Datum	   *values;
+	bool	   *nulls;
+	int		   *dim;
+	int			ndim;
+	int			nitems;
+	int			i;
+	int32		nbytes = 0;
+	int32		dataoffset;
+	bool		hasnulls;
+	Oid			inpType;
+	int			inp_typlen;
+	bool		inp_typbyval;
+	char		inp_typalign;
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	array_iter	iter;
+	ArrayMetaState *inp_extra;
+	ArrayMetaState *ret_extra;
+	Datum	   *transform_source = exprstate->innermost_caseval;
+	bool	   *transform_source_isnull = exprstate->innermost_casenull;
+
+	inpType = AARR_ELEMTYPE(v);
+	ndim = AARR_NDIM(v);
+	dim = AARR_DIMS(v);
+	nitems = ArrayGetNItems(ndim, dim);
+
+	/* Check for empty array */
+	if (nitems <= 0)
+	{
+		/* Return empty array */
+		return PointerGetDatum(construct_empty_array(retType));
+	}
+
+	/*
+	 * We arrange to look up info about input and return element types only
+	 * once per series of calls, assuming the element type doesn't change
+	 * underneath us.
+	 */
+	inp_extra = &amstate->inp_extra;
+	ret_extra = &amstate->ret_extra;
+
+	if (inp_extra->element_type != inpType)
+	{
+		get_typlenbyvalalign(inpType,
+							 &inp_extra->typlen,
+							 &inp_extra->typbyval,
+							 &inp_extra->typalign);
+		inp_extra->element_type = inpType;
+	}
+	inp_typlen = inp_extra->typlen;
+	inp_typbyval = inp_extra->typbyval;
+	inp_typalign = inp_extra->typalign;
+
+	if (ret_extra->element_type != retType)
+	{
+		get_typlenbyvalalign(retType,
+							 &ret_extra->typlen,
+							 &ret_extra->typbyval,
+							 &ret_extra->typalign);
+		ret_extra->element_type = retType;
+	}
+	typlen = ret_extra->typlen;
+	typbyval = ret_extra->typbyval;
+	typalign = ret_extra->typalign;
+
+	/* Allocate temporary arrays for new values */
+	values = (Datum *) palloc(nitems * sizeof(Datum));
+	nulls = (bool *) palloc(nitems * sizeof(bool));
+
+	/* Loop over source data */
+	array_iter_setup(&iter, v);
+	hasnulls = false;
+
+	for (i = 0; i < nitems; i++)
+	{
+		/* Get source element, checking for NULL */
+		*transform_source =
+			array_iter_next(&iter, transform_source_isnull, i,
+							inp_typlen, inp_typbyval, inp_typalign);
+
+		/* Apply the given expression to source element */
+		values[i] = ExecEvalExpr(exprstate, econtext, &nulls[i]);
+
+		if (nulls[i])
+			hasnulls = true;
+		else
+		{
+			/* Ensure data is not toasted */
+			if (typlen == -1)
+				values[i] = PointerGetDatum(PG_DETOAST_DATUM(values[i]));
+			/* Update total result size */
+			nbytes = att_addlength_datum(nbytes, typlen, values[i]);
+			nbytes = att_align_nominal(nbytes, typalign);
+			/* check for overflow of total request */
+			if (!AllocSizeIsValid(nbytes))
+				ereport(ERROR,
+						(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+						 errmsg("array size exceeds the maximum allowed (%d)",
+								(int) MaxAllocSize)));
+		}
+	}
+
+	/* Allocate and fill the result array */
+	if (hasnulls)
+	{
+		dataoffset = ARR_OVERHEAD_WITHNULLS(ndim, nitems);
+		nbytes += dataoffset;
+	}
+	else
+	{
+		dataoffset = 0;			/* marker for no null bitmap */
+		nbytes += ARR_OVERHEAD_NONULLS(ndim);
+	}
+	result = (ArrayType *) palloc0(nbytes);
+	SET_VARSIZE(result, nbytes);
+	result->ndim = ndim;
+	result->dataoffset = dataoffset;
+	result->elemtype = retType;
+	memcpy(ARR_DIMS(result), AARR_DIMS(v), ndim * sizeof(int));
+	memcpy(ARR_LBOUND(result), AARR_LBOUND(v), ndim * sizeof(int));
+
+	CopyArrayEls(result,
+				 values, nulls, nitems,
+				 typlen, typbyval, typalign,
+				 false);
+
+	/*
+	 * Note: do not risk trying to pfree the results of the called expression
+	 */
+	pfree(values);
+	pfree(nulls);
+
+	return PointerGetDatum(result);
+}
+
+/*
+ * construct_array	--- simple method for constructing an array object
+ *
+ * elems: array of Datum items to become the array contents
+ *		  (NULL element values are not supported).
+ * nelems: number of items
+ * elmtype, elmlen, elmbyval, elmalign: info for the datatype of the items
+ *
+ * A palloc'd 1-D array object is constructed and returned.  Note that
+ * elem values will be copied into the object even if pass-by-ref type.
+ * Also note the result will be 0-D not 1-D if nelems = 0.
+ *
+ * NOTE: it would be cleaner to look up the elmlen/elmbval/elmalign info
+ * from the system catalogs, given the elmtype.  However, the caller is
+ * in a better position to cache this info across multiple uses, or even
+ * to hard-wire values if the element type is hard-wired.
+ */
+ArrayType *
+construct_array(Datum *elems, int nelems,
+				Oid elmtype,
+				int elmlen, bool elmbyval, char elmalign)
+{
+	int			dims[1];
+	int			lbs[1];
+
+	dims[0] = nelems;
+	lbs[0] = 1;
+
+	return construct_md_array(elems, NULL, 1, dims, lbs,
+							  elmtype, elmlen, elmbyval, elmalign);
+}
+
+/*
+ * construct_md_array	--- simple method for constructing an array object
+ *							with arbitrary dimensions and possible NULLs
+ *
+ * elems: array of Datum items to become the array contents
+ * nulls: array of is-null flags (can be NULL if no nulls)
+ * ndims: number of dimensions
+ * dims: integer array with size of each dimension
+ * lbs: integer array with lower bound of each dimension
+ * elmtype, elmlen, elmbyval, elmalign: info for the datatype of the items
+ *
+ * A palloc'd ndims-D array object is constructed and returned.  Note that
+ * elem values will be copied into the object even if pass-by-ref type.
+ * Also note the result will be 0-D not ndims-D if any dims[i] = 0.
+ *
+ * NOTE: it would be cleaner to look up the elmlen/elmbval/elmalign info
+ * from the system catalogs, given the elmtype.  However, the caller is
+ * in a better position to cache this info across multiple uses, or even
+ * to hard-wire values if the element type is hard-wired.
+ */
+ArrayType *
+construct_md_array(Datum *elems,
+				   bool *nulls,
+				   int ndims,
+				   int *dims,
+				   int *lbs,
+				   Oid elmtype, int elmlen, bool elmbyval, char elmalign)
+{
+	ArrayType  *result;
+	bool		hasnulls;
+	int32		nbytes;
+	int32		dataoffset;
+	int			i;
+	int			nelems;
+
+	if (ndims < 0)				/* we do allow zero-dimension arrays */
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid number of dimensions: %d", ndims)));
+	if (ndims > MAXDIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+				 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
+						ndims, MAXDIM)));
+
+	/* This checks for overflow of the array dimensions */
+	nelems = ArrayGetNItems(ndims, dims);
+	ArrayCheckBounds(ndims, dims, lbs);
+
+	/* if ndims <= 0 or any dims[i] == 0, return empty array */
+	if (nelems <= 0)
+		return construct_empty_array(elmtype);
+
+	/* compute required space */
+	nbytes = 0;
+	hasnulls = false;
+	for (i = 0; i < nelems; i++)
+	{
+		if (nulls && nulls[i])
+		{
+			hasnulls = true;
+			continue;
+		}
+		/* make sure data is not toasted */
+		if (elmlen == -1)
+			elems[i] = PointerGetDatum(PG_DETOAST_DATUM(elems[i]));
+		nbytes = att_addlength_datum(nbytes, elmlen, elems[i]);
+		nbytes = att_align_nominal(nbytes, elmalign);
+		/* check for overflow of total request */
+		if (!AllocSizeIsValid(nbytes))
+			ereport(ERROR,
+					(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+					 errmsg("array size exceeds the maximum allowed (%d)",
+							(int) MaxAllocSize)));
+	}
+
+	/* Allocate and initialize result array */
+	if (hasnulls)
+	{
+		dataoffset = ARR_OVERHEAD_WITHNULLS(ndims, nelems);
+		nbytes += dataoffset;
+	}
+	else
+	{
+		dataoffset = 0;			/* marker for no null bitmap */
+		nbytes += ARR_OVERHEAD_NONULLS(ndims);
+	}
+	result = (ArrayType *) palloc0(nbytes);
+	SET_VARSIZE(result, nbytes);
+	result->ndim = ndims;
+	result->dataoffset = dataoffset;
+	result->elemtype = elmtype;
+	memcpy(ARR_DIMS(result), dims, ndims * sizeof(int));
+	memcpy(ARR_LBOUND(result), lbs, ndims * sizeof(int));
+
+	CopyArrayEls(result,
+				 elems, nulls, nelems,
+				 elmlen, elmbyval, elmalign,
+				 false);
+
+	return result;
+}
+
+/*
+ * construct_empty_array	--- make a zero-dimensional array of given type
+ */
+ArrayType *
+construct_empty_array(Oid elmtype)
+{
+	ArrayType  *result;
+
+	result = (ArrayType *) palloc0(sizeof(ArrayType));
+	SET_VARSIZE(result, sizeof(ArrayType));
+	result->ndim = 0;
+	result->dataoffset = 0;
+	result->elemtype = elmtype;
+	return result;
+}
+
+/*
+ * construct_empty_expanded_array: make an empty expanded array
+ * given only type information.  (metacache can be NULL if not needed.)
+ */
+ExpandedArrayHeader *
+construct_empty_expanded_array(Oid element_type,
+							   MemoryContext parentcontext,
+							   ArrayMetaState *metacache)
+{
+	ArrayType  *array = construct_empty_array(element_type);
+	Datum		d;
+
+	d = expand_array(PointerGetDatum(array), parentcontext, metacache);
+	pfree(array);
+	return (ExpandedArrayHeader *) DatumGetEOHP(d);
+}
+
+/*
+ * deconstruct_array  --- simple method for extracting data from an array
+ *
+ * array: array object to examine (must not be NULL)
+ * elmtype, elmlen, elmbyval, elmalign: info for the datatype of the items
+ * elemsp: return value, set to point to palloc'd array of Datum values
+ * nullsp: return value, set to point to palloc'd array of isnull markers
+ * nelemsp: return value, set to number of extracted values
+ *
+ * The caller may pass nullsp == NULL if it does not support NULLs in the
+ * array.  Note that this produces a very uninformative error message,
+ * so do it only in cases where a NULL is really not expected.
+ *
+ * If array elements are pass-by-ref data type, the returned Datums will
+ * be pointers into the array object.
+ *
+ * NOTE: it would be cleaner to look up the elmlen/elmbval/elmalign info
+ * from the system catalogs, given the elmtype.  However, in most current
+ * uses the type is hard-wired into the caller and so we can save a lookup
+ * cycle by hard-wiring the type info as well.
+ */
+void
+deconstruct_array(ArrayType *array,
+				  Oid elmtype,
+				  int elmlen, bool elmbyval, char elmalign,
+				  Datum **elemsp, bool **nullsp, int *nelemsp)
+{
+	Datum	   *elems;
+	bool	   *nulls;
+	int			nelems;
+	char	   *p;
+	bits8	   *bitmap;
+	int			bitmask;
+	int			i;
+
+	Assert(ARR_ELEMTYPE(array) == elmtype);
+
+	nelems = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
+	*elemsp = elems = (Datum *) palloc(nelems * sizeof(Datum));
+	if (nullsp)
+		*nullsp = nulls = (bool *) palloc0(nelems * sizeof(bool));
+	else
+		nulls = NULL;
+	*nelemsp = nelems;
+
+	p = ARR_DATA_PTR(array);
+	bitmap = ARR_NULLBITMAP(array);
+	bitmask = 1;
+
+	for (i = 0; i < nelems; i++)
+	{
+		/* Get source element, checking for NULL */
+		if (bitmap && (*bitmap & bitmask) == 0)
+		{
+			elems[i] = (Datum) 0;
+			if (nulls)
+				nulls[i] = true;
+			else
+				ereport(ERROR,
+						(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+						 errmsg("null array element not allowed in this context")));
+		}
+		else
+		{
+			elems[i] = fetch_att(p, elmbyval, elmlen);
+			p = att_addlength_pointer(p, elmlen, p);
+			p = (char *) att_align_nominal(p, elmalign);
+		}
+
+		/* advance bitmap pointer if any */
+		if (bitmap)
+		{
+			bitmask <<= 1;
+			if (bitmask == 0x100)
+			{
+				bitmap++;
+				bitmask = 1;
+			}
+		}
+	}
+}
+
+/*
+ * array_contains_nulls --- detect whether an array has any null elements
+ *
+ * This gives an accurate answer, whereas testing ARR_HASNULL only tells
+ * if the array *might* contain a null.
+ */
+bool
+array_contains_nulls(ArrayType *array)
+{
+	int			nelems;
+	bits8	   *bitmap;
+	int			bitmask;
+
+	/* Easy answer if there's no null bitmap */
+	if (!ARR_HASNULL(array))
+		return false;
+
+	nelems = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
+
+	bitmap = ARR_NULLBITMAP(array);
+
+	/* check whole bytes of the bitmap byte-at-a-time */
+	while (nelems >= 8)
+	{
+		if (*bitmap != 0xFF)
+			return true;
+		bitmap++;
+		nelems -= 8;
+	}
+
+	/* check last partial byte */
+	bitmask = 1;
+	while (nelems > 0)
+	{
+		if ((*bitmap & bitmask) == 0)
+			return true;
+		bitmask <<= 1;
+		nelems--;
+	}
+
+	return false;
+}
+
+
+/*
+ * array_eq :
+ *		  compares two arrays for equality
+ * result :
+ *		  returns true if the arrays are equal, false otherwise.
+ *
+ * Note: we do not use array_cmp here, since equality may be meaningful in
+ * datatypes that don't have a total ordering (and hence no btree support).
+ */
+Datum
+array_eq(PG_FUNCTION_ARGS)
+{
+	LOCAL_FCINFO(locfcinfo, 2);
+	AnyArrayType *array1 = PG_GETARG_ANY_ARRAY_P(0);
+	AnyArrayType *array2 = PG_GETARG_ANY_ARRAY_P(1);
+	Oid			collation = PG_GET_COLLATION();
+	int			ndims1 = AARR_NDIM(array1);
+	int			ndims2 = AARR_NDIM(array2);
+	int		   *dims1 = AARR_DIMS(array1);
+	int		   *dims2 = AARR_DIMS(array2);
+	int		   *lbs1 = AARR_LBOUND(array1);
+	int		   *lbs2 = AARR_LBOUND(array2);
+	Oid			element_type = AARR_ELEMTYPE(array1);
+	bool		result = true;
+	int			nitems;
+	TypeCacheEntry *typentry;
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	array_iter	it1;
+	array_iter	it2;
+	int			i;
+
+	if (element_type != AARR_ELEMTYPE(array2))
+		ereport(ERROR,
+				(errcode(ERRCODE_DATATYPE_MISMATCH),
+				 errmsg("cannot compare arrays of different element types")));
+
+	/* fast path if the arrays do not have the same dimensionality */
+	if (ndims1 != ndims2 ||
+		memcmp(dims1, dims2, ndims1 * sizeof(int)) != 0 ||
+		memcmp(lbs1, lbs2, ndims1 * sizeof(int)) != 0)
+		result = false;
+	else
+	{
+		/*
+		 * We arrange to look up the equality function only once per series of
+		 * calls, assuming the element type doesn't change underneath us.  The
+		 * typcache is used so that we have no memory leakage when being used
+		 * as an index support function.
+		 */
+		typentry = (TypeCacheEntry *) fcinfo->flinfo->fn_extra;
+		if (typentry == NULL ||
+			typentry->type_id != element_type)
+		{
+			typentry = lookup_type_cache(element_type,
+										 TYPECACHE_EQ_OPR_FINFO);
+			if (!OidIsValid(typentry->eq_opr_finfo.fn_oid))
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+						 errmsg("could not identify an equality operator for type %s",
+								format_type_be(element_type))));
+			fcinfo->flinfo->fn_extra = (void *) typentry;
+		}
+		typlen = typentry->typlen;
+		typbyval = typentry->typbyval;
+		typalign = typentry->typalign;
+
+		/*
+		 * apply the operator to each pair of array elements.
+		 */
+		InitFunctionCallInfoData(*locfcinfo, &typentry->eq_opr_finfo, 2,
+								 collation, NULL, NULL);
+
+		/* Loop over source data */
+		nitems = ArrayGetNItems(ndims1, dims1);
+		array_iter_setup(&it1, array1);
+		array_iter_setup(&it2, array2);
+
+		for (i = 0; i < nitems; i++)
+		{
+			Datum		elt1;
+			Datum		elt2;
+			bool		isnull1;
+			bool		isnull2;
+			bool		oprresult;
+
+			/* Get elements, checking for NULL */
+			elt1 = array_iter_next(&it1, &isnull1, i,
+								   typlen, typbyval, typalign);
+			elt2 = array_iter_next(&it2, &isnull2, i,
+								   typlen, typbyval, typalign);
+
+			/*
+			 * We consider two NULLs equal; NULL and not-NULL are unequal.
+			 */
+			if (isnull1 && isnull2)
+				continue;
+			if (isnull1 || isnull2)
+			{
+				result = false;
+				break;
+			}
+
+			/*
+			 * Apply the operator to the element pair; treat NULL as false
+			 */
+			locfcinfo->args[0].value = elt1;
+			locfcinfo->args[0].isnull = false;
+			locfcinfo->args[1].value = elt2;
+			locfcinfo->args[1].isnull = false;
+			locfcinfo->isnull = false;
+			oprresult = DatumGetBool(FunctionCallInvoke(locfcinfo));
+			if (locfcinfo->isnull || !oprresult)
+			{
+				result = false;
+				break;
+			}
+		}
+	}
+
+	/* Avoid leaking memory when handed toasted input. */
+	AARR_FREE_IF_COPY(array1, 0);
+	AARR_FREE_IF_COPY(array2, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+
+/*-----------------------------------------------------------------------------
+ * array-array bool operators:
+ *		Given two arrays, iterate comparison operators
+ *		over the array. Uses logic similar to text comparison
+ *		functions, except element-by-element instead of
+ *		character-by-character.
+ *----------------------------------------------------------------------------
+ */
+
+Datum
+array_ne(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_BOOL(!DatumGetBool(array_eq(fcinfo)));
+}
+
+Datum
+array_lt(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_BOOL(array_cmp(fcinfo) < 0);
+}
+
+Datum
+array_gt(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_BOOL(array_cmp(fcinfo) > 0);
+}
+
+Datum
+array_le(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_BOOL(array_cmp(fcinfo) <= 0);
+}
+
+Datum
+array_ge(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_BOOL(array_cmp(fcinfo) >= 0);
+}
+
+Datum
+btarraycmp(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_INT32(array_cmp(fcinfo));
+}
+
+/*
+ * array_cmp()
+ * Internal comparison function for arrays.
+ *
+ * Returns -1, 0 or 1
+ */
+static int
+array_cmp(FunctionCallInfo fcinfo)
+{
+	LOCAL_FCINFO(locfcinfo, 2);
+	AnyArrayType *array1 = PG_GETARG_ANY_ARRAY_P(0);
+	AnyArrayType *array2 = PG_GETARG_ANY_ARRAY_P(1);
+	Oid			collation = PG_GET_COLLATION();
+	int			ndims1 = AARR_NDIM(array1);
+	int			ndims2 = AARR_NDIM(array2);
+	int		   *dims1 = AARR_DIMS(array1);
+	int		   *dims2 = AARR_DIMS(array2);
+	int			nitems1 = ArrayGetNItems(ndims1, dims1);
+	int			nitems2 = ArrayGetNItems(ndims2, dims2);
+	Oid			element_type = AARR_ELEMTYPE(array1);
+	int			result = 0;
+	TypeCacheEntry *typentry;
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	int			min_nitems;
+	array_iter	it1;
+	array_iter	it2;
+	int			i;
+
+	if (element_type != AARR_ELEMTYPE(array2))
+		ereport(ERROR,
+				(errcode(ERRCODE_DATATYPE_MISMATCH),
+				 errmsg("cannot compare arrays of different element types")));
+
+	/*
+	 * We arrange to look up the comparison function only once per series of
+	 * calls, assuming the element type doesn't change underneath us. The
+	 * typcache is used so that we have no memory leakage when being used as
+	 * an index support function.
+	 */
+	typentry = (TypeCacheEntry *) fcinfo->flinfo->fn_extra;
+	if (typentry == NULL ||
+		typentry->type_id != element_type)
+	{
+		typentry = lookup_type_cache(element_type,
+									 TYPECACHE_CMP_PROC_FINFO);
+		if (!OidIsValid(typentry->cmp_proc_finfo.fn_oid))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("could not identify a comparison function for type %s",
+							format_type_be(element_type))));
+		fcinfo->flinfo->fn_extra = (void *) typentry;
+	}
+	typlen = typentry->typlen;
+	typbyval = typentry->typbyval;
+	typalign = typentry->typalign;
+
+	/*
+	 * apply the operator to each pair of array elements.
+	 */
+	InitFunctionCallInfoData(*locfcinfo, &typentry->cmp_proc_finfo, 2,
+							 collation, NULL, NULL);
+
+	/* Loop over source data */
+	min_nitems = Min(nitems1, nitems2);
+	array_iter_setup(&it1, array1);
+	array_iter_setup(&it2, array2);
+
+	for (i = 0; i < min_nitems; i++)
+	{
+		Datum		elt1;
+		Datum		elt2;
+		bool		isnull1;
+		bool		isnull2;
+		int32		cmpresult;
+
+		/* Get elements, checking for NULL */
+		elt1 = array_iter_next(&it1, &isnull1, i, typlen, typbyval, typalign);
+		elt2 = array_iter_next(&it2, &isnull2, i, typlen, typbyval, typalign);
+
+		/*
+		 * We consider two NULLs equal; NULL > not-NULL.
+		 */
+		if (isnull1 && isnull2)
+			continue;
+		if (isnull1)
+		{
+			/* arg1 is greater than arg2 */
+			result = 1;
+			break;
+		}
+		if (isnull2)
+		{
+			/* arg1 is less than arg2 */
+			result = -1;
+			break;
+		}
+
+		/* Compare the pair of elements */
+		locfcinfo->args[0].value = elt1;
+		locfcinfo->args[0].isnull = false;
+		locfcinfo->args[1].value = elt2;
+		locfcinfo->args[1].isnull = false;
+		cmpresult = DatumGetInt32(FunctionCallInvoke(locfcinfo));
+
+		/* We don't expect comparison support functions to return null */
+		Assert(!locfcinfo->isnull);
+
+		if (cmpresult == 0)
+			continue;			/* equal */
+
+		if (cmpresult < 0)
+		{
+			/* arg1 is less than arg2 */
+			result = -1;
+			break;
+		}
+		else
+		{
+			/* arg1 is greater than arg2 */
+			result = 1;
+			break;
+		}
+	}
+
+	/*
+	 * If arrays contain same data (up to end of shorter one), apply
+	 * additional rules to sort by dimensionality.  The relative significance
+	 * of the different bits of information is historical; mainly we just care
+	 * that we don't say "equal" for arrays of different dimensionality.
+	 */
+	if (result == 0)
+	{
+		if (nitems1 != nitems2)
+			result = (nitems1 < nitems2) ? -1 : 1;
+		else if (ndims1 != ndims2)
+			result = (ndims1 < ndims2) ? -1 : 1;
+		else
+		{
+			for (i = 0; i < ndims1; i++)
+			{
+				if (dims1[i] != dims2[i])
+				{
+					result = (dims1[i] < dims2[i]) ? -1 : 1;
+					break;
+				}
+			}
+			if (result == 0)
+			{
+				int		   *lbound1 = AARR_LBOUND(array1);
+				int		   *lbound2 = AARR_LBOUND(array2);
+
+				for (i = 0; i < ndims1; i++)
+				{
+					if (lbound1[i] != lbound2[i])
+					{
+						result = (lbound1[i] < lbound2[i]) ? -1 : 1;
+						break;
+					}
+				}
+			}
+		}
+	}
+
+	/* Avoid leaking memory when handed toasted input. */
+	AARR_FREE_IF_COPY(array1, 0);
+	AARR_FREE_IF_COPY(array2, 1);
+
+	return result;
+}
+
+
+/*-----------------------------------------------------------------------------
+ * array hashing
+ *		Hash the elements and combine the results.
+ *----------------------------------------------------------------------------
+ */
+
+Datum
+hash_array(PG_FUNCTION_ARGS)
+{
+	LOCAL_FCINFO(locfcinfo, 1);
+	AnyArrayType *array = PG_GETARG_ANY_ARRAY_P(0);
+	int			ndims = AARR_NDIM(array);
+	int		   *dims = AARR_DIMS(array);
+	Oid			element_type = AARR_ELEMTYPE(array);
+	uint32		result = 1;
+	int			nitems;
+	TypeCacheEntry *typentry;
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	int			i;
+	array_iter	iter;
+
+	/*
+	 * We arrange to look up the hash function only once per series of calls,
+	 * assuming the element type doesn't change underneath us.  The typcache
+	 * is used so that we have no memory leakage when being used as an index
+	 * support function.
+	 */
+	typentry = (TypeCacheEntry *) fcinfo->flinfo->fn_extra;
+	if (typentry == NULL ||
+		typentry->type_id != element_type)
+	{
+		typentry = lookup_type_cache(element_type,
+									 TYPECACHE_HASH_PROC_FINFO);
+		if (!OidIsValid(typentry->hash_proc_finfo.fn_oid) && element_type != RECORDOID)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("could not identify a hash function for type %s",
+							format_type_be(element_type))));
+
+		/*
+		 * The type cache doesn't believe that record is hashable (see
+		 * cache_record_field_properties()), but since we're here, we're
+		 * committed to hashing, so we can assume it does.  Worst case, if any
+		 * components of the record don't support hashing, we will fail at
+		 * execution.
+		 */
+		if (element_type == RECORDOID)
+		{
+			MemoryContext oldcontext;
+			TypeCacheEntry *record_typentry;
+
+			oldcontext = MemoryContextSwitchTo(fcinfo->flinfo->fn_mcxt);
+
+			/*
+			 * Make fake type cache entry structure.  Note that we can't just
+			 * modify typentry, since that points directly into the type cache.
+			 */
+			record_typentry = palloc0(sizeof(*record_typentry));
+			record_typentry->type_id = element_type;
+
+			/* fill in what we need below */
+			record_typentry->typlen = typentry->typlen;
+			record_typentry->typbyval = typentry->typbyval;
+			record_typentry->typalign = typentry->typalign;
+			fmgr_info(F_HASH_RECORD, &record_typentry->hash_proc_finfo);
+
+			MemoryContextSwitchTo(oldcontext);
+
+			typentry = record_typentry;
+		}
+
+		fcinfo->flinfo->fn_extra = (void *) typentry;
+	}
+
+	typlen = typentry->typlen;
+	typbyval = typentry->typbyval;
+	typalign = typentry->typalign;
+
+	/*
+	 * apply the hash function to each array element.
+	 */
+	InitFunctionCallInfoData(*locfcinfo, &typentry->hash_proc_finfo, 1,
+							 PG_GET_COLLATION(), NULL, NULL);
+
+	/* Loop over source data */
+	nitems = ArrayGetNItems(ndims, dims);
+	array_iter_setup(&iter, array);
+
+	for (i = 0; i < nitems; i++)
+	{
+		Datum		elt;
+		bool		isnull;
+		uint32		elthash;
+
+		/* Get element, checking for NULL */
+		elt = array_iter_next(&iter, &isnull, i, typlen, typbyval, typalign);
+
+		if (isnull)
+		{
+			/* Treat nulls as having hashvalue 0 */
+			elthash = 0;
+		}
+		else
+		{
+			/* Apply the hash function */
+			locfcinfo->args[0].value = elt;
+			locfcinfo->args[0].isnull = false;
+			elthash = DatumGetUInt32(FunctionCallInvoke(locfcinfo));
+			/* We don't expect hash functions to return null */
+			Assert(!locfcinfo->isnull);
+		}
+
+		/*
+		 * Combine hash values of successive elements by multiplying the
+		 * current value by 31 and adding on the new element's hash value.
+		 *
+		 * The result is a sum in which each element's hash value is
+		 * multiplied by a different power of 31. This is modulo 2^32
+		 * arithmetic, and the powers of 31 modulo 2^32 form a cyclic group of
+		 * order 2^27. So for arrays of up to 2^27 elements, each element's
+		 * hash value is multiplied by a different (odd) number, resulting in
+		 * a good mixing of all the elements' hash values.
+		 */
+		result = (result << 5) - result + elthash;
+	}
+
+	/* Avoid leaking memory when handed toasted input. */
+	AARR_FREE_IF_COPY(array, 0);
+
+	PG_RETURN_UINT32(result);
+}
+
+/*
+ * Returns 64-bit value by hashing a value to a 64-bit value, with a seed.
+ * Otherwise, similar to hash_array.
+ */
+Datum
+hash_array_extended(PG_FUNCTION_ARGS)
+{
+	LOCAL_FCINFO(locfcinfo, 2);
+	AnyArrayType *array = PG_GETARG_ANY_ARRAY_P(0);
+	uint64		seed = PG_GETARG_INT64(1);
+	int			ndims = AARR_NDIM(array);
+	int		   *dims = AARR_DIMS(array);
+	Oid			element_type = AARR_ELEMTYPE(array);
+	uint64		result = 1;
+	int			nitems;
+	TypeCacheEntry *typentry;
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	int			i;
+	array_iter	iter;
+
+	typentry = (TypeCacheEntry *) fcinfo->flinfo->fn_extra;
+	if (typentry == NULL ||
+		typentry->type_id != element_type)
+	{
+		typentry = lookup_type_cache(element_type,
+									 TYPECACHE_HASH_EXTENDED_PROC_FINFO);
+		if (!OidIsValid(typentry->hash_extended_proc_finfo.fn_oid))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("could not identify an extended hash function for type %s",
+							format_type_be(element_type))));
+		fcinfo->flinfo->fn_extra = (void *) typentry;
+	}
+	typlen = typentry->typlen;
+	typbyval = typentry->typbyval;
+	typalign = typentry->typalign;
+
+	InitFunctionCallInfoData(*locfcinfo, &typentry->hash_extended_proc_finfo, 2,
+							 PG_GET_COLLATION(), NULL, NULL);
+
+	/* Loop over source data */
+	nitems = ArrayGetNItems(ndims, dims);
+	array_iter_setup(&iter, array);
+
+	for (i = 0; i < nitems; i++)
+	{
+		Datum		elt;
+		bool		isnull;
+		uint64		elthash;
+
+		/* Get element, checking for NULL */
+		elt = array_iter_next(&iter, &isnull, i, typlen, typbyval, typalign);
+
+		if (isnull)
+		{
+			elthash = 0;
+		}
+		else
+		{
+			/* Apply the hash function */
+			locfcinfo->args[0].value = elt;
+			locfcinfo->args[0].isnull = false;
+			locfcinfo->args[1].value = Int64GetDatum(seed);
+			locfcinfo->args[1].isnull = false;
+			elthash = DatumGetUInt64(FunctionCallInvoke(locfcinfo));
+			/* We don't expect hash functions to return null */
+			Assert(!locfcinfo->isnull);
+		}
+
+		result = (result << 5) - result + elthash;
+	}
+
+	AARR_FREE_IF_COPY(array, 0);
+
+	PG_RETURN_UINT64(result);
+}
+
+
+/*-----------------------------------------------------------------------------
+ * array overlap/containment comparisons
+ *		These use the same methods of comparing array elements as array_eq.
+ *		We consider only the elements of the arrays, ignoring dimensionality.
+ *----------------------------------------------------------------------------
+ */
+
+/*
+ * array_contain_compare :
+ *		  compares two arrays for overlap/containment
+ *
+ * When matchall is true, return true if all members of array1 are in array2.
+ * When matchall is false, return true if any members of array1 are in array2.
+ */
+static bool
+array_contain_compare(AnyArrayType *array1, AnyArrayType *array2, Oid collation,
+					  bool matchall, void **fn_extra)
+{
+	LOCAL_FCINFO(locfcinfo, 2);
+	bool		result = matchall;
+	Oid			element_type = AARR_ELEMTYPE(array1);
+	TypeCacheEntry *typentry;
+	int			nelems1;
+	Datum	   *values2;
+	bool	   *nulls2;
+	int			nelems2;
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	int			i;
+	int			j;
+	array_iter	it1;
+
+	if (element_type != AARR_ELEMTYPE(array2))
+		ereport(ERROR,
+				(errcode(ERRCODE_DATATYPE_MISMATCH),
+				 errmsg("cannot compare arrays of different element types")));
+
+	/*
+	 * We arrange to look up the equality function only once per series of
+	 * calls, assuming the element type doesn't change underneath us.  The
+	 * typcache is used so that we have no memory leakage when being used as
+	 * an index support function.
+	 */
+	typentry = (TypeCacheEntry *) *fn_extra;
+	if (typentry == NULL ||
+		typentry->type_id != element_type)
+	{
+		typentry = lookup_type_cache(element_type,
+									 TYPECACHE_EQ_OPR_FINFO);
+		if (!OidIsValid(typentry->eq_opr_finfo.fn_oid))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("could not identify an equality operator for type %s",
+							format_type_be(element_type))));
+		*fn_extra = (void *) typentry;
+	}
+	typlen = typentry->typlen;
+	typbyval = typentry->typbyval;
+	typalign = typentry->typalign;
+
+	/*
+	 * Since we probably will need to scan array2 multiple times, it's
+	 * worthwhile to use deconstruct_array on it.  We scan array1 the hard way
+	 * however, since we very likely won't need to look at all of it.
+	 */
+	if (VARATT_IS_EXPANDED_HEADER(array2))
+	{
+		/* This should be safe even if input is read-only */
+		deconstruct_expanded_array(&(array2->xpn));
+		values2 = array2->xpn.dvalues;
+		nulls2 = array2->xpn.dnulls;
+		nelems2 = array2->xpn.nelems;
+	}
+	else
+		deconstruct_array((ArrayType *) array2,
+						  element_type, typlen, typbyval, typalign,
+						  &values2, &nulls2, &nelems2);
+
+	/*
+	 * Apply the comparison operator to each pair of array elements.
+	 */
+	InitFunctionCallInfoData(*locfcinfo, &typentry->eq_opr_finfo, 2,
+							 collation, NULL, NULL);
+
+	/* Loop over source data */
+	nelems1 = ArrayGetNItems(AARR_NDIM(array1), AARR_DIMS(array1));
+	array_iter_setup(&it1, array1);
+
+	for (i = 0; i < nelems1; i++)
+	{
+		Datum		elt1;
+		bool		isnull1;
+
+		/* Get element, checking for NULL */
+		elt1 = array_iter_next(&it1, &isnull1, i, typlen, typbyval, typalign);
+
+		/*
+		 * We assume that the comparison operator is strict, so a NULL can't
+		 * match anything.  XXX this diverges from the "NULL=NULL" behavior of
+		 * array_eq, should we act like that?
+		 */
+		if (isnull1)
+		{
+			if (matchall)
+			{
+				result = false;
+				break;
+			}
+			continue;
+		}
+
+		for (j = 0; j < nelems2; j++)
+		{
+			Datum		elt2 = values2[j];
+			bool		isnull2 = nulls2 ? nulls2[j] : false;
+			bool		oprresult;
+
+			if (isnull2)
+				continue;		/* can't match */
+
+			/*
+			 * Apply the operator to the element pair; treat NULL as false
+			 */
+			locfcinfo->args[0].value = elt1;
+			locfcinfo->args[0].isnull = false;
+			locfcinfo->args[1].value = elt2;
+			locfcinfo->args[1].isnull = false;
+			locfcinfo->isnull = false;
+			oprresult = DatumGetBool(FunctionCallInvoke(locfcinfo));
+			if (!locfcinfo->isnull && oprresult)
+				break;
+		}
+
+		if (j < nelems2)
+		{
+			/* found a match for elt1 */
+			if (!matchall)
+			{
+				result = true;
+				break;
+			}
+		}
+		else
+		{
+			/* no match for elt1 */
+			if (matchall)
+			{
+				result = false;
+				break;
+			}
+		}
+	}
+
+	return result;
+}
+
+Datum
+arrayoverlap(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *array1 = PG_GETARG_ANY_ARRAY_P(0);
+	AnyArrayType *array2 = PG_GETARG_ANY_ARRAY_P(1);
+	Oid			collation = PG_GET_COLLATION();
+	bool		result;
+
+	result = array_contain_compare(array1, array2, collation, false,
+								   &fcinfo->flinfo->fn_extra);
+
+	/* Avoid leaking memory when handed toasted input. */
+	AARR_FREE_IF_COPY(array1, 0);
+	AARR_FREE_IF_COPY(array2, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+Datum
+arraycontains(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *array1 = PG_GETARG_ANY_ARRAY_P(0);
+	AnyArrayType *array2 = PG_GETARG_ANY_ARRAY_P(1);
+	Oid			collation = PG_GET_COLLATION();
+	bool		result;
+
+	result = array_contain_compare(array2, array1, collation, true,
+								   &fcinfo->flinfo->fn_extra);
+
+	/* Avoid leaking memory when handed toasted input. */
+	AARR_FREE_IF_COPY(array1, 0);
+	AARR_FREE_IF_COPY(array2, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+Datum
+arraycontained(PG_FUNCTION_ARGS)
+{
+	AnyArrayType *array1 = PG_GETARG_ANY_ARRAY_P(0);
+	AnyArrayType *array2 = PG_GETARG_ANY_ARRAY_P(1);
+	Oid			collation = PG_GET_COLLATION();
+	bool		result;
+
+	result = array_contain_compare(array1, array2, collation, true,
+								   &fcinfo->flinfo->fn_extra);
+
+	/* Avoid leaking memory when handed toasted input. */
+	AARR_FREE_IF_COPY(array1, 0);
+	AARR_FREE_IF_COPY(array2, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+
+/*-----------------------------------------------------------------------------
+ * Array iteration functions
+ *		These functions are used to iterate efficiently through arrays
+ *-----------------------------------------------------------------------------
+ */
+
+/*
+ * array_create_iterator --- set up to iterate through an array
+ *
+ * If slice_ndim is zero, we will iterate element-by-element; the returned
+ * datums are of the array's element type.
+ *
+ * If slice_ndim is 1..ARR_NDIM(arr), we will iterate by slices: the
+ * returned datums are of the same array type as 'arr', but of size
+ * equal to the rightmost N dimensions of 'arr'.
+ *
+ * The passed-in array must remain valid for the lifetime of the iterator.
+ */
+ArrayIterator
+array_create_iterator(ArrayType *arr, int slice_ndim, ArrayMetaState *mstate)
+{
+	ArrayIterator iterator = palloc0(sizeof(ArrayIteratorData));
+
+	/*
+	 * Sanity-check inputs --- caller should have got this right already
+	 */
+	Assert(PointerIsValid(arr));
+	if (slice_ndim < 0 || slice_ndim > ARR_NDIM(arr))
+		elog(ERROR, "invalid arguments to array_create_iterator");
+
+	/*
+	 * Remember basic info about the array and its element type
+	 */
+	iterator->arr = arr;
+	iterator->nullbitmap = ARR_NULLBITMAP(arr);
+	iterator->nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
+
+	if (mstate != NULL)
+	{
+		Assert(mstate->element_type == ARR_ELEMTYPE(arr));
+
+		iterator->typlen = mstate->typlen;
+		iterator->typbyval = mstate->typbyval;
+		iterator->typalign = mstate->typalign;
+	}
+	else
+		get_typlenbyvalalign(ARR_ELEMTYPE(arr),
+							 &iterator->typlen,
+							 &iterator->typbyval,
+							 &iterator->typalign);
+
+	/*
+	 * Remember the slicing parameters.
+	 */
+	iterator->slice_ndim = slice_ndim;
+
+	if (slice_ndim > 0)
+	{
+		/*
+		 * Get pointers into the array's dims and lbound arrays to represent
+		 * the dims/lbound arrays of a slice.  These are the same as the
+		 * rightmost N dimensions of the array.
+		 */
+		iterator->slice_dims = ARR_DIMS(arr) + ARR_NDIM(arr) - slice_ndim;
+		iterator->slice_lbound = ARR_LBOUND(arr) + ARR_NDIM(arr) - slice_ndim;
+
+		/*
+		 * Compute number of elements in a slice.
+		 */
+		iterator->slice_len = ArrayGetNItems(slice_ndim,
+											 iterator->slice_dims);
+
+		/*
+		 * Create workspace for building sub-arrays.
+		 */
+		iterator->slice_values = (Datum *)
+			palloc(iterator->slice_len * sizeof(Datum));
+		iterator->slice_nulls = (bool *)
+			palloc(iterator->slice_len * sizeof(bool));
+	}
+
+	/*
+	 * Initialize our data pointer and linear element number.  These will
+	 * advance through the array during array_iterate().
+	 */
+	iterator->data_ptr = ARR_DATA_PTR(arr);
+	iterator->current_item = 0;
+
+	return iterator;
+}
+
+/*
+ * Iterate through the array referenced by 'iterator'.
+ *
+ * As long as there is another element (or slice), return it into
+ * *value / *isnull, and return true.  Return false when no more data.
+ */
+bool
+array_iterate(ArrayIterator iterator, Datum *value, bool *isnull)
+{
+	/* Done if we have reached the end of the array */
+	if (iterator->current_item >= iterator->nitems)
+		return false;
+
+	if (iterator->slice_ndim == 0)
+	{
+		/*
+		 * Scalar case: return one element.
+		 */
+		if (array_get_isnull(iterator->nullbitmap, iterator->current_item++))
+		{
+			*isnull = true;
+			*value = (Datum) 0;
+		}
+		else
+		{
+			/* non-NULL, so fetch the individual Datum to return */
+			char	   *p = iterator->data_ptr;
+
+			*isnull = false;
+			*value = fetch_att(p, iterator->typbyval, iterator->typlen);
+
+			/* Move our data pointer forward to the next element */
+			p = att_addlength_pointer(p, iterator->typlen, p);
+			p = (char *) att_align_nominal(p, iterator->typalign);
+			iterator->data_ptr = p;
+		}
+	}
+	else
+	{
+		/*
+		 * Slice case: build and return an array of the requested size.
+		 */
+		ArrayType  *result;
+		Datum	   *values = iterator->slice_values;
+		bool	   *nulls = iterator->slice_nulls;
+		char	   *p = iterator->data_ptr;
+		int			i;
+
+		for (i = 0; i < iterator->slice_len; i++)
+		{
+			if (array_get_isnull(iterator->nullbitmap,
+								 iterator->current_item++))
+			{
+				nulls[i] = true;
+				values[i] = (Datum) 0;
+			}
+			else
+			{
+				nulls[i] = false;
+				values[i] = fetch_att(p, iterator->typbyval, iterator->typlen);
+
+				/* Move our data pointer forward to the next element */
+				p = att_addlength_pointer(p, iterator->typlen, p);
+				p = (char *) att_align_nominal(p, iterator->typalign);
+			}
+		}
+
+		iterator->data_ptr = p;
+
+		result = construct_md_array(values,
+									nulls,
+									iterator->slice_ndim,
+									iterator->slice_dims,
+									iterator->slice_lbound,
+									ARR_ELEMTYPE(iterator->arr),
+									iterator->typlen,
+									iterator->typbyval,
+									iterator->typalign);
+
+		*isnull = false;
+		*value = PointerGetDatum(result);
+	}
+
+	return true;
+}
+
+/*
+ * Release an ArrayIterator data structure
+ */
+void
+array_free_iterator(ArrayIterator iterator)
+{
+	if (iterator->slice_ndim > 0)
+	{
+		pfree(iterator->slice_values);
+		pfree(iterator->slice_nulls);
+	}
+	pfree(iterator);
+}
+
+
+/***************************************************************************/
+/******************|		  Support  Routines			  |*****************/
+/***************************************************************************/
+
+/*
+ * Check whether a specific array element is NULL
+ *
+ * nullbitmap: pointer to array's null bitmap (NULL if none)
+ * offset: 0-based linear element number of array element
+ */
+static bool
+array_get_isnull(const bits8 *nullbitmap, int offset)
+{
+	if (nullbitmap == NULL)
+		return false;			/* assume not null */
+	if (nullbitmap[offset / 8] & (1 << (offset % 8)))
+		return false;			/* not null */
+	return true;
+}
+
+/*
+ * Set a specific array element's null-bitmap entry
+ *
+ * nullbitmap: pointer to array's null bitmap (mustn't be NULL)
+ * offset: 0-based linear element number of array element
+ * isNull: null status to set
+ */
+static void
+array_set_isnull(bits8 *nullbitmap, int offset, bool isNull)
+{
+	int			bitmask;
+
+	nullbitmap += offset / 8;
+	bitmask = 1 << (offset % 8);
+	if (isNull)
+		*nullbitmap &= ~bitmask;
+	else
+		*nullbitmap |= bitmask;
+}
+
+/*
+ * Fetch array element at pointer, converted correctly to a Datum
+ *
+ * Caller must have handled case of NULL element
+ */
+static Datum
+ArrayCast(char *value, bool byval, int len)
+{
+	return fetch_att(value, byval, len);
+}
+
+/*
+ * Copy datum to *dest and return total space used (including align padding)
+ *
+ * Caller must have handled case of NULL element
+ */
+static int
+ArrayCastAndSet(Datum src,
+				int typlen,
+				bool typbyval,
+				char typalign,
+				char *dest)
+{
+	int			inc;
+
+	if (typlen > 0)
+	{
+		if (typbyval)
+			store_att_byval(dest, src, typlen);
+		else
+			memmove(dest, DatumGetPointer(src), typlen);
+		inc = att_align_nominal(typlen, typalign);
+	}
+	else
+	{
+		Assert(!typbyval);
+		inc = att_addlength_datum(0, typlen, src);
+		memmove(dest, DatumGetPointer(src), inc);
+		inc = att_align_nominal(inc, typalign);
+	}
+
+	return inc;
+}
+
+/*
+ * Advance ptr over nitems array elements
+ *
+ * ptr: starting location in array
+ * offset: 0-based linear element number of first element (the one at *ptr)
+ * nullbitmap: start of array's null bitmap, or NULL if none
+ * nitems: number of array elements to advance over (>= 0)
+ * typlen, typbyval, typalign: storage parameters of array element datatype
+ *
+ * It is caller's responsibility to ensure that nitems is within range
+ */
+static char *
+array_seek(char *ptr, int offset, bits8 *nullbitmap, int nitems,
+		   int typlen, bool typbyval, char typalign)
+{
+	int			bitmask;
+	int			i;
+
+	/* easy if fixed-size elements and no NULLs */
+	if (typlen > 0 && !nullbitmap)
+		return ptr + nitems * ((Size) att_align_nominal(typlen, typalign));
+
+	/* seems worth having separate loops for NULL and no-NULLs cases */
+	if (nullbitmap)
+	{
+		nullbitmap += offset / 8;
+		bitmask = 1 << (offset % 8);
+
+		for (i = 0; i < nitems; i++)
+		{
+			if (*nullbitmap & bitmask)
+			{
+				ptr = att_addlength_pointer(ptr, typlen, ptr);
+				ptr = (char *) att_align_nominal(ptr, typalign);
+			}
+			bitmask <<= 1;
+			if (bitmask == 0x100)
+			{
+				nullbitmap++;
+				bitmask = 1;
+			}
+		}
+	}
+	else
+	{
+		for (i = 0; i < nitems; i++)
+		{
+			ptr = att_addlength_pointer(ptr, typlen, ptr);
+			ptr = (char *) att_align_nominal(ptr, typalign);
+		}
+	}
+	return ptr;
+}
+
+/*
+ * Compute total size of the nitems array elements starting at *ptr
+ *
+ * Parameters same as for array_seek
+ */
+static int
+array_nelems_size(char *ptr, int offset, bits8 *nullbitmap, int nitems,
+				  int typlen, bool typbyval, char typalign)
+{
+	return array_seek(ptr, offset, nullbitmap, nitems,
+					  typlen, typbyval, typalign) - ptr;
+}
+
+/*
+ * Copy nitems array elements from srcptr to destptr
+ *
+ * destptr: starting destination location (must be enough room!)
+ * nitems: number of array elements to copy (>= 0)
+ * srcptr: starting location in source array
+ * offset: 0-based linear element number of first element (the one at *srcptr)
+ * nullbitmap: start of source array's null bitmap, or NULL if none
+ * typlen, typbyval, typalign: storage parameters of array element datatype
+ *
+ * Returns number of bytes copied
+ *
+ * NB: this does not take care of setting up the destination's null bitmap!
+ */
+static int
+array_copy(char *destptr, int nitems,
+		   char *srcptr, int offset, bits8 *nullbitmap,
+		   int typlen, bool typbyval, char typalign)
+{
+	int			numbytes;
+
+	numbytes = array_nelems_size(srcptr, offset, nullbitmap, nitems,
+								 typlen, typbyval, typalign);
+	memcpy(destptr, srcptr, numbytes);
+	return numbytes;
+}
+
+/*
+ * Copy nitems null-bitmap bits from source to destination
+ *
+ * destbitmap: start of destination array's null bitmap (mustn't be NULL)
+ * destoffset: 0-based linear element number of first dest element
+ * srcbitmap: start of source array's null bitmap, or NULL if none
+ * srcoffset: 0-based linear element number of first source element
+ * nitems: number of bits to copy (>= 0)
+ *
+ * If srcbitmap is NULL then we assume the source is all-non-NULL and
+ * fill 1's into the destination bitmap.  Note that only the specified
+ * bits in the destination map are changed, not any before or after.
+ *
+ * Note: this could certainly be optimized using standard bitblt methods.
+ * However, it's not clear that the typical Postgres array has enough elements
+ * to make it worth worrying too much.  For the moment, KISS.
+ */
+void
+array_bitmap_copy(bits8 *destbitmap, int destoffset,
+				  const bits8 *srcbitmap, int srcoffset,
+				  int nitems)
+{
+	int			destbitmask,
+				destbitval,
+				srcbitmask,
+				srcbitval;
+
+	Assert(destbitmap);
+	if (nitems <= 0)
+		return;					/* don't risk fetch off end of memory */
+	destbitmap += destoffset / 8;
+	destbitmask = 1 << (destoffset % 8);
+	destbitval = *destbitmap;
+	if (srcbitmap)
+	{
+		srcbitmap += srcoffset / 8;
+		srcbitmask = 1 << (srcoffset % 8);
+		srcbitval = *srcbitmap;
+		while (nitems-- > 0)
+		{
+			if (srcbitval & srcbitmask)
+				destbitval |= destbitmask;
+			else
+				destbitval &= ~destbitmask;
+			destbitmask <<= 1;
+			if (destbitmask == 0x100)
+			{
+				*destbitmap++ = destbitval;
+				destbitmask = 1;
+				if (nitems > 0)
+					destbitval = *destbitmap;
+			}
+			srcbitmask <<= 1;
+			if (srcbitmask == 0x100)
+			{
+				srcbitmap++;
+				srcbitmask = 1;
+				if (nitems > 0)
+					srcbitval = *srcbitmap;
+			}
+		}
+		if (destbitmask != 1)
+			*destbitmap = destbitval;
+	}
+	else
+	{
+		while (nitems-- > 0)
+		{
+			destbitval |= destbitmask;
+			destbitmask <<= 1;
+			if (destbitmask == 0x100)
+			{
+				*destbitmap++ = destbitval;
+				destbitmask = 1;
+				if (nitems > 0)
+					destbitval = *destbitmap;
+			}
+		}
+		if (destbitmask != 1)
+			*destbitmap = destbitval;
+	}
+}
+
+/*
+ * Compute space needed for a slice of an array
+ *
+ * We assume the caller has verified that the slice coordinates are valid.
+ */
+static int
+array_slice_size(char *arraydataptr, bits8 *arraynullsptr,
+				 int ndim, int *dim, int *lb,
+				 int *st, int *endp,
+				 int typlen, bool typbyval, char typalign)
+{
+	int			src_offset,
+				span[MAXDIM],
+				prod[MAXDIM],
+				dist[MAXDIM],
+				indx[MAXDIM];
+	char	   *ptr;
+	int			i,
+				j,
+				inc;
+	int			count = 0;
+
+	mda_get_range(ndim, span, st, endp);
+
+	/* Pretty easy for fixed element length without nulls ... */
+	if (typlen > 0 && !arraynullsptr)
+		return ArrayGetNItems(ndim, span) * att_align_nominal(typlen, typalign);
+
+	/* Else gotta do it the hard way */
+	src_offset = ArrayGetOffset(ndim, dim, lb, st);
+	ptr = array_seek(arraydataptr, 0, arraynullsptr, src_offset,
+					 typlen, typbyval, typalign);
+	mda_get_prod(ndim, dim, prod);
+	mda_get_offset_values(ndim, dist, prod, span);
+	for (i = 0; i < ndim; i++)
+		indx[i] = 0;
+	j = ndim - 1;
+	do
+	{
+		if (dist[j])
+		{
+			ptr = array_seek(ptr, src_offset, arraynullsptr, dist[j],
+							 typlen, typbyval, typalign);
+			src_offset += dist[j];
+		}
+		if (!array_get_isnull(arraynullsptr, src_offset))
+		{
+			inc = att_addlength_pointer(0, typlen, ptr);
+			inc = att_align_nominal(inc, typalign);
+			ptr += inc;
+			count += inc;
+		}
+		src_offset++;
+	} while ((j = mda_next_tuple(ndim, indx, span)) != -1);
+	return count;
+}
+
+/*
+ * Extract a slice of an array into consecutive elements in the destination
+ * array.
+ *
+ * We assume the caller has verified that the slice coordinates are valid,
+ * allocated enough storage for the result, and initialized the header
+ * of the new array.
+ */
+static void
+array_extract_slice(ArrayType *newarray,
+					int ndim,
+					int *dim,
+					int *lb,
+					char *arraydataptr,
+					bits8 *arraynullsptr,
+					int *st,
+					int *endp,
+					int typlen,
+					bool typbyval,
+					char typalign)
+{
+	char	   *destdataptr = ARR_DATA_PTR(newarray);
+	bits8	   *destnullsptr = ARR_NULLBITMAP(newarray);
+	char	   *srcdataptr;
+	int			src_offset,
+				dest_offset,
+				prod[MAXDIM],
+				span[MAXDIM],
+				dist[MAXDIM],
+				indx[MAXDIM];
+	int			i,
+				j,
+				inc;
+
+	src_offset = ArrayGetOffset(ndim, dim, lb, st);
+	srcdataptr = array_seek(arraydataptr, 0, arraynullsptr, src_offset,
+							typlen, typbyval, typalign);
+	mda_get_prod(ndim, dim, prod);
+	mda_get_range(ndim, span, st, endp);
+	mda_get_offset_values(ndim, dist, prod, span);
+	for (i = 0; i < ndim; i++)
+		indx[i] = 0;
+	dest_offset = 0;
+	j = ndim - 1;
+	do
+	{
+		if (dist[j])
+		{
+			/* skip unwanted elements */
+			srcdataptr = array_seek(srcdataptr, src_offset, arraynullsptr,
+									dist[j],
+									typlen, typbyval, typalign);
+			src_offset += dist[j];
+		}
+		inc = array_copy(destdataptr, 1,
+						 srcdataptr, src_offset, arraynullsptr,
+						 typlen, typbyval, typalign);
+		if (destnullsptr)
+			array_bitmap_copy(destnullsptr, dest_offset,
+							  arraynullsptr, src_offset,
+							  1);
+		destdataptr += inc;
+		srcdataptr += inc;
+		src_offset++;
+		dest_offset++;
+	} while ((j = mda_next_tuple(ndim, indx, span)) != -1);
+}
+
+/*
+ * Insert a slice into an array.
+ *
+ * ndim/dim[]/lb[] are dimensions of the original array.  A new array with
+ * those same dimensions is to be constructed.  destArray must already
+ * have been allocated and its header initialized.
+ *
+ * st[]/endp[] identify the slice to be replaced.  Elements within the slice
+ * volume are taken from consecutive elements of the srcArray; elements
+ * outside it are copied from origArray.
+ *
+ * We assume the caller has verified that the slice coordinates are valid.
+ */
+static void
+array_insert_slice(ArrayType *destArray,
+				   ArrayType *origArray,
+				   ArrayType *srcArray,
+				   int ndim,
+				   int *dim,
+				   int *lb,
+				   int *st,
+				   int *endp,
+				   int typlen,
+				   bool typbyval,
+				   char typalign)
+{
+	char	   *destPtr = ARR_DATA_PTR(destArray);
+	char	   *origPtr = ARR_DATA_PTR(origArray);
+	char	   *srcPtr = ARR_DATA_PTR(srcArray);
+	bits8	   *destBitmap = ARR_NULLBITMAP(destArray);
+	bits8	   *origBitmap = ARR_NULLBITMAP(origArray);
+	bits8	   *srcBitmap = ARR_NULLBITMAP(srcArray);
+	int			orignitems = ArrayGetNItems(ARR_NDIM(origArray),
+											ARR_DIMS(origArray));
+	int			dest_offset,
+				orig_offset,
+				src_offset,
+				prod[MAXDIM],
+				span[MAXDIM],
+				dist[MAXDIM],
+				indx[MAXDIM];
+	int			i,
+				j,
+				inc;
+
+	dest_offset = ArrayGetOffset(ndim, dim, lb, st);
+	/* copy items before the slice start */
+	inc = array_copy(destPtr, dest_offset,
+					 origPtr, 0, origBitmap,
+					 typlen, typbyval, typalign);
+	destPtr += inc;
+	origPtr += inc;
+	if (destBitmap)
+		array_bitmap_copy(destBitmap, 0, origBitmap, 0, dest_offset);
+	orig_offset = dest_offset;
+	mda_get_prod(ndim, dim, prod);
+	mda_get_range(ndim, span, st, endp);
+	mda_get_offset_values(ndim, dist, prod, span);
+	for (i = 0; i < ndim; i++)
+		indx[i] = 0;
+	src_offset = 0;
+	j = ndim - 1;
+	do
+	{
+		/* Copy/advance over elements between here and next part of slice */
+		if (dist[j])
+		{
+			inc = array_copy(destPtr, dist[j],
+							 origPtr, orig_offset, origBitmap,
+							 typlen, typbyval, typalign);
+			destPtr += inc;
+			origPtr += inc;
+			if (destBitmap)
+				array_bitmap_copy(destBitmap, dest_offset,
+								  origBitmap, orig_offset,
+								  dist[j]);
+			dest_offset += dist[j];
+			orig_offset += dist[j];
+		}
+		/* Copy new element at this slice position */
+		inc = array_copy(destPtr, 1,
+						 srcPtr, src_offset, srcBitmap,
+						 typlen, typbyval, typalign);
+		if (destBitmap)
+			array_bitmap_copy(destBitmap, dest_offset,
+							  srcBitmap, src_offset,
+							  1);
+		destPtr += inc;
+		srcPtr += inc;
+		dest_offset++;
+		src_offset++;
+		/* Advance over old element at this slice position */
+		origPtr = array_seek(origPtr, orig_offset, origBitmap, 1,
+							 typlen, typbyval, typalign);
+		orig_offset++;
+	} while ((j = mda_next_tuple(ndim, indx, span)) != -1);
+
+	/* don't miss any data at the end */
+	array_copy(destPtr, orignitems - orig_offset,
+			   origPtr, orig_offset, origBitmap,
+			   typlen, typbyval, typalign);
+	if (destBitmap)
+		array_bitmap_copy(destBitmap, dest_offset,
+						  origBitmap, orig_offset,
+						  orignitems - orig_offset);
+}
+
+/*
+ * initArrayResult - initialize an empty ArrayBuildState
+ *
+ *	element_type is the array element type (must be a valid array element type)
+ *	rcontext is where to keep working state
+ *	subcontext is a flag determining whether to use a separate memory context
+ *
+ * Note: there are two common schemes for using accumArrayResult().
+ * In the older scheme, you start with a NULL ArrayBuildState pointer, and
+ * call accumArrayResult once per element.  In this scheme you end up with
+ * a NULL pointer if there were no elements, which you need to special-case.
+ * In the newer scheme, call initArrayResult and then call accumArrayResult
+ * once per element.  In this scheme you always end with a non-NULL pointer
+ * that you can pass to makeArrayResult; you get an empty array if there
+ * were no elements.  This is preferred if an empty array is what you want.
+ *
+ * It's possible to choose whether to create a separate memory context for the
+ * array build state, or whether to allocate it directly within rcontext.
+ *
+ * When there are many concurrent small states (e.g. array_agg() using hash
+ * aggregation of many small groups), using a separate memory context for each
+ * one may result in severe memory bloat. In such cases, use the same memory
+ * context to initialize all such array build states, and pass
+ * subcontext=false.
+ *
+ * In cases when the array build states have different lifetimes, using a
+ * single memory context is impractical. Instead, pass subcontext=true so that
+ * the array build states can be freed individually.
+ */
+ArrayBuildState *
+initArrayResult(Oid element_type, MemoryContext rcontext, bool subcontext)
+{
+	ArrayBuildState *astate;
+	MemoryContext arr_context = rcontext;
+
+	/* Make a temporary context to hold all the junk */
+	if (subcontext)
+		arr_context = AllocSetContextCreate(rcontext,
+											"accumArrayResult",
+											ALLOCSET_DEFAULT_SIZES);
+
+	astate = (ArrayBuildState *)
+		MemoryContextAlloc(arr_context, sizeof(ArrayBuildState));
+	astate->mcontext = arr_context;
+	astate->private_cxt = subcontext;
+	astate->alen = (subcontext ? 64 : 8);	/* arbitrary starting array size */
+	astate->dvalues = (Datum *)
+		MemoryContextAlloc(arr_context, astate->alen * sizeof(Datum));
+	astate->dnulls = (bool *)
+		MemoryContextAlloc(arr_context, astate->alen * sizeof(bool));
+	astate->nelems = 0;
+	astate->element_type = element_type;
+	get_typlenbyvalalign(element_type,
+						 &astate->typlen,
+						 &astate->typbyval,
+						 &astate->typalign);
+
+	return astate;
+}
+
+/*
+ * accumArrayResult - accumulate one (more) Datum for an array result
+ *
+ *	astate is working state (can be NULL on first call)
+ *	dvalue/disnull represent the new Datum to append to the array
+ *	element_type is the Datum's type (must be a valid array element type)
+ *	rcontext is where to keep working state
+ */
+ArrayBuildState *
+accumArrayResult(ArrayBuildState *astate,
+				 Datum dvalue, bool disnull,
+				 Oid element_type,
+				 MemoryContext rcontext)
+{
+	MemoryContext oldcontext;
+
+	if (astate == NULL)
+	{
+		/* First time through --- initialize */
+		astate = initArrayResult(element_type, rcontext, true);
+	}
+	else
+	{
+		Assert(astate->element_type == element_type);
+	}
+
+	oldcontext = MemoryContextSwitchTo(astate->mcontext);
+
+	/* enlarge dvalues[]/dnulls[] if needed */
+	if (astate->nelems >= astate->alen)
+	{
+		astate->alen *= 2;
+		astate->dvalues = (Datum *)
+			repalloc(astate->dvalues, astate->alen * sizeof(Datum));
+		astate->dnulls = (bool *)
+			repalloc(astate->dnulls, astate->alen * sizeof(bool));
+	}
+
+	/*
+	 * Ensure pass-by-ref stuff is copied into mcontext; and detoast it too if
+	 * it's varlena.  (You might think that detoasting is not needed here
+	 * because construct_md_array can detoast the array elements later.
+	 * However, we must not let construct_md_array modify the ArrayBuildState
+	 * because that would mean array_agg_finalfn damages its input, which is
+	 * verboten.  Also, this way frequently saves one copying step.)
+	 */
+	if (!disnull && !astate->typbyval)
+	{
+		if (astate->typlen == -1)
+			dvalue = PointerGetDatum(PG_DETOAST_DATUM_COPY(dvalue));
+		else
+			dvalue = datumCopy(dvalue, astate->typbyval, astate->typlen);
+	}
+
+	astate->dvalues[astate->nelems] = dvalue;
+	astate->dnulls[astate->nelems] = disnull;
+	astate->nelems++;
+
+	MemoryContextSwitchTo(oldcontext);
+
+	return astate;
+}
+
+/*
+ * makeArrayResult - produce 1-D final result of accumArrayResult
+ *
+ * Note: only releases astate if it was initialized within a separate memory
+ * context (i.e. using subcontext=true when calling initArrayResult).
+ *
+ *	astate is working state (must not be NULL)
+ *	rcontext is where to construct result
+ */
+Datum
+makeArrayResult(ArrayBuildState *astate,
+				MemoryContext rcontext)
+{
+	int			ndims;
+	int			dims[1];
+	int			lbs[1];
+
+	/* If no elements were presented, we want to create an empty array */
+	ndims = (astate->nelems > 0) ? 1 : 0;
+	dims[0] = astate->nelems;
+	lbs[0] = 1;
+
+	return makeMdArrayResult(astate, ndims, dims, lbs, rcontext,
+							 astate->private_cxt);
+}
+
+/*
+ * makeMdArrayResult - produce multi-D final result of accumArrayResult
+ *
+ * beware: no check that specified dimensions match the number of values
+ * accumulated.
+ *
+ * Note: if the astate was not initialized within a separate memory context
+ * (that is, initArrayResult was called with subcontext=false), then using
+ * release=true is illegal. Instead, release astate along with the rest of its
+ * context when appropriate.
+ *
+ *	astate is working state (must not be NULL)
+ *	rcontext is where to construct result
+ *	release is true if okay to release working state
+ */
+Datum
+makeMdArrayResult(ArrayBuildState *astate,
+				  int ndims,
+				  int *dims,
+				  int *lbs,
+				  MemoryContext rcontext,
+				  bool release)
+{
+	ArrayType  *result;
+	MemoryContext oldcontext;
+
+	/* Build the final array result in rcontext */
+	oldcontext = MemoryContextSwitchTo(rcontext);
+
+	result = construct_md_array(astate->dvalues,
+								astate->dnulls,
+								ndims,
+								dims,
+								lbs,
+								astate->element_type,
+								astate->typlen,
+								astate->typbyval,
+								astate->typalign);
+
+	MemoryContextSwitchTo(oldcontext);
+
+	/* Clean up all the junk */
+	if (release)
+	{
+		Assert(astate->private_cxt);
+		MemoryContextDelete(astate->mcontext);
+	}
+
+	return PointerGetDatum(result);
+}
+
+/*
+ * The following three functions provide essentially the same API as
+ * initArrayResult/accumArrayResult/makeArrayResult, but instead of accepting
+ * inputs that are array elements, they accept inputs that are arrays and
+ * produce an output array having N+1 dimensions.  The inputs must all have
+ * identical dimensionality as well as element type.
+ */
+
+/*
+ * initArrayResultArr - initialize an empty ArrayBuildStateArr
+ *
+ *	array_type is the array type (must be a valid varlena array type)
+ *	element_type is the type of the array's elements (lookup if InvalidOid)
+ *	rcontext is where to keep working state
+ *	subcontext is a flag determining whether to use a separate memory context
+ */
+ArrayBuildStateArr *
+initArrayResultArr(Oid array_type, Oid element_type, MemoryContext rcontext,
+				   bool subcontext)
+{
+	ArrayBuildStateArr *astate;
+	MemoryContext arr_context = rcontext;	/* by default use the parent ctx */
+
+	/* Lookup element type, unless element_type already provided */
+	if (!OidIsValid(element_type))
+	{
+		element_type = get_element_type(array_type);
+
+		if (!OidIsValid(element_type))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("data type %s is not an array type",
+							format_type_be(array_type))));
+	}
+
+	/* Make a temporary context to hold all the junk */
+	if (subcontext)
+		arr_context = AllocSetContextCreate(rcontext,
+											"accumArrayResultArr",
+											ALLOCSET_DEFAULT_SIZES);
+
+	/* Note we initialize all fields to zero */
+	astate = (ArrayBuildStateArr *)
+		MemoryContextAllocZero(arr_context, sizeof(ArrayBuildStateArr));
+	astate->mcontext = arr_context;
+	astate->private_cxt = subcontext;
+
+	/* Save relevant datatype information */
+	astate->array_type = array_type;
+	astate->element_type = element_type;
+
+	return astate;
+}
+
+/*
+ * accumArrayResultArr - accumulate one (more) sub-array for an array result
+ *
+ *	astate is working state (can be NULL on first call)
+ *	dvalue/disnull represent the new sub-array to append to the array
+ *	array_type is the array type (must be a valid varlena array type)
+ *	rcontext is where to keep working state
+ */
+ArrayBuildStateArr *
+accumArrayResultArr(ArrayBuildStateArr *astate,
+					Datum dvalue, bool disnull,
+					Oid array_type,
+					MemoryContext rcontext)
+{
+	ArrayType  *arg;
+	MemoryContext oldcontext;
+	int		   *dims,
+			   *lbs,
+				ndims,
+				nitems,
+				ndatabytes;
+	char	   *data;
+	int			i;
+
+	/*
+	 * We disallow accumulating null subarrays.  Another plausible definition
+	 * is to ignore them, but callers that want that can just skip calling
+	 * this function.
+	 */
+	if (disnull)
+		ereport(ERROR,
+				(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+				 errmsg("cannot accumulate null arrays")));
+
+	/* Detoast input array in caller's context */
+	arg = DatumGetArrayTypeP(dvalue);
+
+	if (astate == NULL)
+		astate = initArrayResultArr(array_type, InvalidOid, rcontext, true);
+	else
+		Assert(astate->array_type == array_type);
+
+	oldcontext = MemoryContextSwitchTo(astate->mcontext);
+
+	/* Collect this input's dimensions */
+	ndims = ARR_NDIM(arg);
+	dims = ARR_DIMS(arg);
+	lbs = ARR_LBOUND(arg);
+	data = ARR_DATA_PTR(arg);
+	nitems = ArrayGetNItems(ndims, dims);
+	ndatabytes = ARR_SIZE(arg) - ARR_DATA_OFFSET(arg);
+
+	if (astate->ndims == 0)
+	{
+		/* First input; check/save the dimensionality info */
+
+		/* Should we allow empty inputs and just produce an empty output? */
+		if (ndims == 0)
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("cannot accumulate empty arrays")));
+		if (ndims + 1 > MAXDIM)
+			ereport(ERROR,
+					(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+					 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
+							ndims + 1, MAXDIM)));
+
+		/*
+		 * The output array will have n+1 dimensions, with the ones after the
+		 * first matching the input's dimensions.
+		 */
+		astate->ndims = ndims + 1;
+		astate->dims[0] = 0;
+		memcpy(&astate->dims[1], dims, ndims * sizeof(int));
+		astate->lbs[0] = 1;
+		memcpy(&astate->lbs[1], lbs, ndims * sizeof(int));
+
+		/* Allocate at least enough data space for this item */
+		astate->abytes = pg_nextpower2_32(Max(1024, ndatabytes + 1));
+		astate->data = (char *) palloc(astate->abytes);
+	}
+	else
+	{
+		/* Second or later input: must match first input's dimensionality */
+		if (astate->ndims != ndims + 1)
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("cannot accumulate arrays of different dimensionality")));
+		for (i = 0; i < ndims; i++)
+		{
+			if (astate->dims[i + 1] != dims[i] || astate->lbs[i + 1] != lbs[i])
+				ereport(ERROR,
+						(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+						 errmsg("cannot accumulate arrays of different dimensionality")));
+		}
+
+		/* Enlarge data space if needed */
+		if (astate->nbytes + ndatabytes > astate->abytes)
+		{
+			astate->abytes = Max(astate->abytes * 2,
+								 astate->nbytes + ndatabytes);
+			astate->data = (char *) repalloc(astate->data, astate->abytes);
+		}
+	}
+
+	/*
+	 * Copy the data portion of the sub-array.  Note we assume that the
+	 * advertised data length of the sub-array is properly aligned.  We do not
+	 * have to worry about detoasting elements since whatever's in the
+	 * sub-array should be OK already.
+	 */
+	memcpy(astate->data + astate->nbytes, data, ndatabytes);
+	astate->nbytes += ndatabytes;
+
+	/* Deal with null bitmap if needed */
+	if (astate->nullbitmap || ARR_HASNULL(arg))
+	{
+		int			newnitems = astate->nitems + nitems;
+
+		if (astate->nullbitmap == NULL)
+		{
+			/*
+			 * First input with nulls; we must retrospectively handle any
+			 * previous inputs by marking all their items non-null.
+			 */
+			astate->aitems = pg_nextpower2_32(Max(256, newnitems + 1));
+			astate->nullbitmap = (bits8 *) palloc((astate->aitems + 7) / 8);
+			array_bitmap_copy(astate->nullbitmap, 0,
+							  NULL, 0,
+							  astate->nitems);
+		}
+		else if (newnitems > astate->aitems)
+		{
+			astate->aitems = Max(astate->aitems * 2, newnitems);
+			astate->nullbitmap = (bits8 *)
+				repalloc(astate->nullbitmap, (astate->aitems + 7) / 8);
+		}
+		array_bitmap_copy(astate->nullbitmap, astate->nitems,
+						  ARR_NULLBITMAP(arg), 0,
+						  nitems);
+	}
+
+	astate->nitems += nitems;
+	astate->dims[0] += 1;
+
+	MemoryContextSwitchTo(oldcontext);
+
+	/* Release detoasted copy if any */
+	if ((Pointer) arg != DatumGetPointer(dvalue))
+		pfree(arg);
+
+	return astate;
+}
+
+/*
+ * makeArrayResultArr - produce N+1-D final result of accumArrayResultArr
+ *
+ *	astate is working state (must not be NULL)
+ *	rcontext is where to construct result
+ *	release is true if okay to release working state
+ */
+Datum
+makeArrayResultArr(ArrayBuildStateArr *astate,
+				   MemoryContext rcontext,
+				   bool release)
+{
+	ArrayType  *result;
+	MemoryContext oldcontext;
+
+	/* Build the final array result in rcontext */
+	oldcontext = MemoryContextSwitchTo(rcontext);
+
+	if (astate->ndims == 0)
+	{
+		/* No inputs, return empty array */
+		result = construct_empty_array(astate->element_type);
+	}
+	else
+	{
+		int			dataoffset,
+					nbytes;
+
+		/* Check for overflow of the array dimensions */
+		(void) ArrayGetNItems(astate->ndims, astate->dims);
+		ArrayCheckBounds(astate->ndims, astate->dims, astate->lbs);
+
+		/* Compute required space */
+		nbytes = astate->nbytes;
+		if (astate->nullbitmap != NULL)
+		{
+			dataoffset = ARR_OVERHEAD_WITHNULLS(astate->ndims, astate->nitems);
+			nbytes += dataoffset;
+		}
+		else
+		{
+			dataoffset = 0;
+			nbytes += ARR_OVERHEAD_NONULLS(astate->ndims);
+		}
+
+		result = (ArrayType *) palloc0(nbytes);
+		SET_VARSIZE(result, nbytes);
+		result->ndim = astate->ndims;
+		result->dataoffset = dataoffset;
+		result->elemtype = astate->element_type;
+
+		memcpy(ARR_DIMS(result), astate->dims, astate->ndims * sizeof(int));
+		memcpy(ARR_LBOUND(result), astate->lbs, astate->ndims * sizeof(int));
+		memcpy(ARR_DATA_PTR(result), astate->data, astate->nbytes);
+
+		if (astate->nullbitmap != NULL)
+			array_bitmap_copy(ARR_NULLBITMAP(result), 0,
+							  astate->nullbitmap, 0,
+							  astate->nitems);
+	}
+
+	MemoryContextSwitchTo(oldcontext);
+
+	/* Clean up all the junk */
+	if (release)
+	{
+		Assert(astate->private_cxt);
+		MemoryContextDelete(astate->mcontext);
+	}
+
+	return PointerGetDatum(result);
+}
+
+/*
+ * The following three functions provide essentially the same API as
+ * initArrayResult/accumArrayResult/makeArrayResult, but can accept either
+ * scalar or array inputs, invoking the appropriate set of functions above.
+ */
+
+/*
+ * initArrayResultAny - initialize an empty ArrayBuildStateAny
+ *
+ *	input_type is the input datatype (either element or array type)
+ *	rcontext is where to keep working state
+ *	subcontext is a flag determining whether to use a separate memory context
+ */
+ArrayBuildStateAny *
+initArrayResultAny(Oid input_type, MemoryContext rcontext, bool subcontext)
+{
+	ArrayBuildStateAny *astate;
+	Oid			element_type = get_element_type(input_type);
+
+	if (OidIsValid(element_type))
+	{
+		/* Array case */
+		ArrayBuildStateArr *arraystate;
+
+		arraystate = initArrayResultArr(input_type, InvalidOid, rcontext, subcontext);
+		astate = (ArrayBuildStateAny *)
+			MemoryContextAlloc(arraystate->mcontext,
+							   sizeof(ArrayBuildStateAny));
+		astate->scalarstate = NULL;
+		astate->arraystate = arraystate;
+	}
+	else
+	{
+		/* Scalar case */
+		ArrayBuildState *scalarstate;
+
+		/* Let's just check that we have a type that can be put into arrays */
+		Assert(OidIsValid(get_array_type(input_type)));
+
+		scalarstate = initArrayResult(input_type, rcontext, subcontext);
+		astate = (ArrayBuildStateAny *)
+			MemoryContextAlloc(scalarstate->mcontext,
+							   sizeof(ArrayBuildStateAny));
+		astate->scalarstate = scalarstate;
+		astate->arraystate = NULL;
+	}
+
+	return astate;
+}
+
+/*
+ * accumArrayResultAny - accumulate one (more) input for an array result
+ *
+ *	astate is working state (can be NULL on first call)
+ *	dvalue/disnull represent the new input to append to the array
+ *	input_type is the input datatype (either element or array type)
+ *	rcontext is where to keep working state
+ */
+ArrayBuildStateAny *
+accumArrayResultAny(ArrayBuildStateAny *astate,
+					Datum dvalue, bool disnull,
+					Oid input_type,
+					MemoryContext rcontext)
+{
+	if (astate == NULL)
+		astate = initArrayResultAny(input_type, rcontext, true);
+
+	if (astate->scalarstate)
+		(void) accumArrayResult(astate->scalarstate,
+								dvalue, disnull,
+								input_type, rcontext);
+	else
+		(void) accumArrayResultArr(astate->arraystate,
+								   dvalue, disnull,
+								   input_type, rcontext);
+
+	return astate;
+}
+
+/*
+ * makeArrayResultAny - produce final result of accumArrayResultAny
+ *
+ *	astate is working state (must not be NULL)
+ *	rcontext is where to construct result
+ *	release is true if okay to release working state
+ */
+Datum
+makeArrayResultAny(ArrayBuildStateAny *astate,
+				   MemoryContext rcontext, bool release)
+{
+	Datum		result;
+
+	if (astate->scalarstate)
+	{
+		/* Must use makeMdArrayResult to support "release" parameter */
+		int			ndims;
+		int			dims[1];
+		int			lbs[1];
+
+		/* If no elements were presented, we want to create an empty array */
+		ndims = (astate->scalarstate->nelems > 0) ? 1 : 0;
+		dims[0] = astate->scalarstate->nelems;
+		lbs[0] = 1;
+
+		result = makeMdArrayResult(astate->scalarstate, ndims, dims, lbs,
+								   rcontext, release);
+	}
+	else
+	{
+		result = makeArrayResultArr(astate->arraystate,
+									rcontext, release);
+	}
+	return result;
+}
+
+
+Datum
+array_larger(PG_FUNCTION_ARGS)
+{
+	if (array_cmp(fcinfo) > 0)
+		PG_RETURN_DATUM(PG_GETARG_DATUM(0));
+	else
+		PG_RETURN_DATUM(PG_GETARG_DATUM(1));
+}
+
+Datum
+array_smaller(PG_FUNCTION_ARGS)
+{
+	if (array_cmp(fcinfo) < 0)
+		PG_RETURN_DATUM(PG_GETARG_DATUM(0));
+	else
+		PG_RETURN_DATUM(PG_GETARG_DATUM(1));
+}
+
+
+typedef struct generate_subscripts_fctx
+{
+	int32		lower;
+	int32		upper;
+	bool		reverse;
+} generate_subscripts_fctx;
+
+/*
+ * generate_subscripts(array anyarray, dim int [, reverse bool])
+ *		Returns all subscripts of the array for any dimension
+ */
+Datum
+generate_subscripts(PG_FUNCTION_ARGS)
+{
+	FuncCallContext *funcctx;
+	MemoryContext oldcontext;
+	generate_subscripts_fctx *fctx;
+
+	/* stuff done only on the first call of the function */
+	if (SRF_IS_FIRSTCALL())
+	{
+		AnyArrayType *v = PG_GETARG_ANY_ARRAY_P(0);
+		int			reqdim = PG_GETARG_INT32(1);
+		int		   *lb,
+				   *dimv;
+
+		/* create a function context for cross-call persistence */
+		funcctx = SRF_FIRSTCALL_INIT();
+
+		/* Sanity check: does it look like an array at all? */
+		if (AARR_NDIM(v) <= 0 || AARR_NDIM(v) > MAXDIM)
+			SRF_RETURN_DONE(funcctx);
+
+		/* Sanity check: was the requested dim valid */
+		if (reqdim <= 0 || reqdim > AARR_NDIM(v))
+			SRF_RETURN_DONE(funcctx);
+
+		/*
+		 * switch to memory context appropriate for multiple function calls
+		 */
+		oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
+		fctx = (generate_subscripts_fctx *) palloc(sizeof(generate_subscripts_fctx));
+
+		lb = AARR_LBOUND(v);
+		dimv = AARR_DIMS(v);
+
+		fctx->lower = lb[reqdim - 1];
+		fctx->upper = dimv[reqdim - 1] + lb[reqdim - 1] - 1;
+		fctx->reverse = (PG_NARGS() < 3) ? false : PG_GETARG_BOOL(2);
+
+		funcctx->user_fctx = fctx;
+
+		MemoryContextSwitchTo(oldcontext);
+	}
+
+	funcctx = SRF_PERCALL_SETUP();
+
+	fctx = funcctx->user_fctx;
+
+	if (fctx->lower <= fctx->upper)
+	{
+		if (!fctx->reverse)
+			SRF_RETURN_NEXT(funcctx, Int32GetDatum(fctx->lower++));
+		else
+			SRF_RETURN_NEXT(funcctx, Int32GetDatum(fctx->upper--));
+	}
+	else
+		/* done when there are no more elements left */
+		SRF_RETURN_DONE(funcctx);
+}
+
+/*
+ * generate_subscripts_nodir
+ *		Implements the 2-argument version of generate_subscripts
+ */
+Datum
+generate_subscripts_nodir(PG_FUNCTION_ARGS)
+{
+	/* just call the other one -- it can handle both cases */
+	return generate_subscripts(fcinfo);
+}
+
+/*
+ * array_fill_with_lower_bounds
+ *		Create and fill array with defined lower bounds.
+ */
+Datum
+array_fill_with_lower_bounds(PG_FUNCTION_ARGS)
+{
+	ArrayType  *dims;
+	ArrayType  *lbs;
+	ArrayType  *result;
+	Oid			elmtype;
+	Datum		value;
+	bool		isnull;
+
+	if (PG_ARGISNULL(1) || PG_ARGISNULL(2))
+		ereport(ERROR,
+				(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+				 errmsg("dimension array or low bound array cannot be null")));
+
+	dims = PG_GETARG_ARRAYTYPE_P(1);
+	lbs = PG_GETARG_ARRAYTYPE_P(2);
+
+	if (!PG_ARGISNULL(0))
+	{
+		value = PG_GETARG_DATUM(0);
+		isnull = false;
+	}
+	else
+	{
+		value = 0;
+		isnull = true;
+	}
+
+	elmtype = get_fn_expr_argtype(fcinfo->flinfo, 0);
+	if (!OidIsValid(elmtype))
+		elog(ERROR, "could not determine data type of input");
+
+	result = array_fill_internal(dims, lbs, value, isnull, elmtype, fcinfo);
+	PG_RETURN_ARRAYTYPE_P(result);
+}
+
+/*
+ * array_fill
+ *		Create and fill array with default lower bounds.
+ */
+Datum
+array_fill(PG_FUNCTION_ARGS)
+{
+	ArrayType  *dims;
+	ArrayType  *result;
+	Oid			elmtype;
+	Datum		value;
+	bool		isnull;
+
+	if (PG_ARGISNULL(1))
+		ereport(ERROR,
+				(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+				 errmsg("dimension array or low bound array cannot be null")));
+
+	dims = PG_GETARG_ARRAYTYPE_P(1);
+
+	if (!PG_ARGISNULL(0))
+	{
+		value = PG_GETARG_DATUM(0);
+		isnull = false;
+	}
+	else
+	{
+		value = 0;
+		isnull = true;
+	}
+
+	elmtype = get_fn_expr_argtype(fcinfo->flinfo, 0);
+	if (!OidIsValid(elmtype))
+		elog(ERROR, "could not determine data type of input");
+
+	result = array_fill_internal(dims, NULL, value, isnull, elmtype, fcinfo);
+	PG_RETURN_ARRAYTYPE_P(result);
+}
+
+static ArrayType *
+create_array_envelope(int ndims, int *dimv, int *lbsv, int nbytes,
+					  Oid elmtype, int dataoffset)
+{
+	ArrayType  *result;
+
+	result = (ArrayType *) palloc0(nbytes);
+	SET_VARSIZE(result, nbytes);
+	result->ndim = ndims;
+	result->dataoffset = dataoffset;
+	result->elemtype = elmtype;
+	memcpy(ARR_DIMS(result), dimv, ndims * sizeof(int));
+	memcpy(ARR_LBOUND(result), lbsv, ndims * sizeof(int));
+
+	return result;
+}
+
+static ArrayType *
+array_fill_internal(ArrayType *dims, ArrayType *lbs,
+					Datum value, bool isnull, Oid elmtype,
+					FunctionCallInfo fcinfo)
+{
+	ArrayType  *result;
+	int		   *dimv;
+	int		   *lbsv;
+	int			ndims;
+	int			nitems;
+	int			deflbs[MAXDIM];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	ArrayMetaState *my_extra;
+
+	/*
+	 * Params checks
+	 */
+	if (ARR_NDIM(dims) > 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("wrong number of array subscripts"),
+				 errdetail("Dimension array must be one dimensional.")));
+
+	if (array_contains_nulls(dims))
+		ereport(ERROR,
+				(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+				 errmsg("dimension values cannot be null")));
+
+	dimv = (int *) ARR_DATA_PTR(dims);
+	ndims = (ARR_NDIM(dims) > 0) ? ARR_DIMS(dims)[0] : 0;
+
+	if (ndims < 0)				/* we do allow zero-dimension arrays */
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid number of dimensions: %d", ndims)));
+	if (ndims > MAXDIM)
+		ereport(ERROR,
+				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+				 errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
+						ndims, MAXDIM)));
+
+	if (lbs != NULL)
+	{
+		if (ARR_NDIM(lbs) > 1)
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("wrong number of array subscripts"),
+					 errdetail("Dimension array must be one dimensional.")));
+
+		if (array_contains_nulls(lbs))
+			ereport(ERROR,
+					(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+					 errmsg("dimension values cannot be null")));
+
+		if (ndims != ((ARR_NDIM(lbs) > 0) ? ARR_DIMS(lbs)[0] : 0))
+			ereport(ERROR,
+					(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+					 errmsg("wrong number of array subscripts"),
+					 errdetail("Low bound array has different size than dimensions array.")));
+
+		lbsv = (int *) ARR_DATA_PTR(lbs);
+	}
+	else
+	{
+		int			i;
+
+		for (i = 0; i < MAXDIM; i++)
+			deflbs[i] = 1;
+
+		lbsv = deflbs;
+	}
+
+	/* This checks for overflow of the array dimensions */
+	nitems = ArrayGetNItems(ndims, dimv);
+	ArrayCheckBounds(ndims, dimv, lbsv);
+
+	/* fast track for empty array */
+	if (nitems <= 0)
+		return construct_empty_array(elmtype);
+
+	/*
+	 * We arrange to look up info about element type only once per series of
+	 * calls, assuming the element type doesn't change underneath us.
+	 */
+	my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL)
+	{
+		fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+													  sizeof(ArrayMetaState));
+		my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra;
+		my_extra->element_type = InvalidOid;
+	}
+
+	if (my_extra->element_type != elmtype)
+	{
+		/* Get info about element type */
+		get_typlenbyvalalign(elmtype,
+							 &my_extra->typlen,
+							 &my_extra->typbyval,
+							 &my_extra->typalign);
+		my_extra->element_type = elmtype;
+	}
+
+	elmlen = my_extra->typlen;
+	elmbyval = my_extra->typbyval;
+	elmalign = my_extra->typalign;
+
+	/* compute required space */
+	if (!isnull)
+	{
+		int			i;
+		char	   *p;
+		int			nbytes;
+		int			totbytes;
+
+		/* make sure data is not toasted */
+		if (elmlen == -1)
+			value = PointerGetDatum(PG_DETOAST_DATUM(value));
+
+		nbytes = att_addlength_datum(0, elmlen, value);
+		nbytes = att_align_nominal(nbytes, elmalign);
+		Assert(nbytes > 0);
+
+		totbytes = nbytes * nitems;
+
+		/* check for overflow of multiplication or total request */
+		if (totbytes / nbytes != nitems ||
+			!AllocSizeIsValid(totbytes))
+			ereport(ERROR,
+					(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+					 errmsg("array size exceeds the maximum allowed (%d)",
+							(int) MaxAllocSize)));
+
+		/*
+		 * This addition can't overflow, but it might cause us to go past
+		 * MaxAllocSize.  We leave it to palloc to complain in that case.
+		 */
+		totbytes += ARR_OVERHEAD_NONULLS(ndims);
+
+		result = create_array_envelope(ndims, dimv, lbsv, totbytes,
+									   elmtype, 0);
+
+		p = ARR_DATA_PTR(result);
+		for (i = 0; i < nitems; i++)
+			p += ArrayCastAndSet(value, elmlen, elmbyval, elmalign, p);
+	}
+	else
+	{
+		int			nbytes;
+		int			dataoffset;
+
+		dataoffset = ARR_OVERHEAD_WITHNULLS(ndims, nitems);
+		nbytes = dataoffset;
+
+		result = create_array_envelope(ndims, dimv, lbsv, nbytes,
+									   elmtype, dataoffset);
+
+		/* create_array_envelope already zeroed the bitmap, so we're done */
+	}
+
+	return result;
+}
+
+
+/*
+ * UNNEST
+ */
+Datum
+array_unnest(PG_FUNCTION_ARGS)
+{
+	typedef struct
+	{
+		array_iter	iter;
+		int			nextelem;
+		int			numelems;
+		int16		elmlen;
+		bool		elmbyval;
+		char		elmalign;
+	} array_unnest_fctx;
+
+	FuncCallContext *funcctx;
+	array_unnest_fctx *fctx;
+	MemoryContext oldcontext;
+
+	/* stuff done only on the first call of the function */
+	if (SRF_IS_FIRSTCALL())
+	{
+		AnyArrayType *arr;
+
+		/* create a function context for cross-call persistence */
+		funcctx = SRF_FIRSTCALL_INIT();
+
+		/*
+		 * switch to memory context appropriate for multiple function calls
+		 */
+		oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
+
+		/*
+		 * Get the array value and detoast if needed.  We can't do this
+		 * earlier because if we have to detoast, we want the detoasted copy
+		 * to be in multi_call_memory_ctx, so it will go away when we're done
+		 * and not before.  (If no detoast happens, we assume the originally
+		 * passed array will stick around till then.)
+		 */
+		arr = PG_GETARG_ANY_ARRAY_P(0);
+
+		/* allocate memory for user context */
+		fctx = (array_unnest_fctx *) palloc(sizeof(array_unnest_fctx));
+
+		/* initialize state */
+		array_iter_setup(&fctx->iter, arr);
+		fctx->nextelem = 0;
+		fctx->numelems = ArrayGetNItems(AARR_NDIM(arr), AARR_DIMS(arr));
+
+		if (VARATT_IS_EXPANDED_HEADER(arr))
+		{
+			/* we can just grab the type data from expanded array */
+			fctx->elmlen = arr->xpn.typlen;
+			fctx->elmbyval = arr->xpn.typbyval;
+			fctx->elmalign = arr->xpn.typalign;
+		}
+		else
+			get_typlenbyvalalign(AARR_ELEMTYPE(arr),
+								 &fctx->elmlen,
+								 &fctx->elmbyval,
+								 &fctx->elmalign);
+
+		funcctx->user_fctx = fctx;
+		MemoryContextSwitchTo(oldcontext);
+	}
+
+	/* stuff done on every call of the function */
+	funcctx = SRF_PERCALL_SETUP();
+	fctx = funcctx->user_fctx;
+
+	if (fctx->nextelem < fctx->numelems)
+	{
+		int			offset = fctx->nextelem++;
+		Datum		elem;
+
+		elem = array_iter_next(&fctx->iter, &fcinfo->isnull, offset,
+							   fctx->elmlen, fctx->elmbyval, fctx->elmalign);
+
+		SRF_RETURN_NEXT(funcctx, elem);
+	}
+	else
+	{
+		/* do when there is no more left */
+		SRF_RETURN_DONE(funcctx);
+	}
+}
+
+/*
+ * Planner support function for array_unnest(anyarray)
+ */
+Datum
+array_unnest_support(PG_FUNCTION_ARGS)
+{
+	Node	   *rawreq = (Node *) PG_GETARG_POINTER(0);
+	Node	   *ret = NULL;
+
+	if (IsA(rawreq, SupportRequestRows))
+	{
+		/* Try to estimate the number of rows returned */
+		SupportRequestRows *req = (SupportRequestRows *) rawreq;
+
+		if (is_funcclause(req->node))	/* be paranoid */
+		{
+			List	   *args = ((FuncExpr *) req->node)->args;
+			Node	   *arg1;
+
+			/* We can use estimated argument values here */
+			arg1 = estimate_expression_value(req->root, linitial(args));
+
+			req->rows = estimate_array_length(arg1);
+			ret = (Node *) req;
+		}
+	}
+
+	PG_RETURN_POINTER(ret);
+}
+
+
+/*
+ * array_replace/array_remove support
+ *
+ * Find all array entries matching (not distinct from) search/search_isnull,
+ * and delete them if remove is true, else replace them with
+ * replace/replace_isnull.  Comparisons are done using the specified
+ * collation.  fcinfo is passed only for caching purposes.
+ */
+static ArrayType *
+array_replace_internal(ArrayType *array,
+					   Datum search, bool search_isnull,
+					   Datum replace, bool replace_isnull,
+					   bool remove, Oid collation,
+					   FunctionCallInfo fcinfo)
+{
+	LOCAL_FCINFO(locfcinfo, 2);
+	ArrayType  *result;
+	Oid			element_type;
+	Datum	   *values;
+	bool	   *nulls;
+	int		   *dim;
+	int			ndim;
+	int			nitems,
+				nresult;
+	int			i;
+	int32		nbytes = 0;
+	int32		dataoffset;
+	bool		hasnulls;
+	int			typlen;
+	bool		typbyval;
+	char		typalign;
+	char	   *arraydataptr;
+	bits8	   *bitmap;
+	int			bitmask;
+	bool		changed = false;
+	TypeCacheEntry *typentry;
+
+	element_type = ARR_ELEMTYPE(array);
+	ndim = ARR_NDIM(array);
+	dim = ARR_DIMS(array);
+	nitems = ArrayGetNItems(ndim, dim);
+
+	/* Return input array unmodified if it is empty */
+	if (nitems <= 0)
+		return array;
+
+	/*
+	 * We can't remove elements from multi-dimensional arrays, since the
+	 * result might not be rectangular.
+	 */
+	if (remove && ndim > 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("removing elements from multidimensional arrays is not supported")));
+
+	/*
+	 * We arrange to look up the equality function only once per series of
+	 * calls, assuming the element type doesn't change underneath us.
+	 */
+	typentry = (TypeCacheEntry *) fcinfo->flinfo->fn_extra;
+	if (typentry == NULL ||
+		typentry->type_id != element_type)
+	{
+		typentry = lookup_type_cache(element_type,
+									 TYPECACHE_EQ_OPR_FINFO);
+		if (!OidIsValid(typentry->eq_opr_finfo.fn_oid))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("could not identify an equality operator for type %s",
+							format_type_be(element_type))));
+		fcinfo->flinfo->fn_extra = (void *) typentry;
+	}
+	typlen = typentry->typlen;
+	typbyval = typentry->typbyval;
+	typalign = typentry->typalign;
+
+	/*
+	 * Detoast values if they are toasted.  The replacement value must be
+	 * detoasted for insertion into the result array, while detoasting the
+	 * search value only once saves cycles.
+	 */
+	if (typlen == -1)
+	{
+		if (!search_isnull)
+			search = PointerGetDatum(PG_DETOAST_DATUM(search));
+		if (!replace_isnull)
+			replace = PointerGetDatum(PG_DETOAST_DATUM(replace));
+	}
+
+	/* Prepare to apply the comparison operator */
+	InitFunctionCallInfoData(*locfcinfo, &typentry->eq_opr_finfo, 2,
+							 collation, NULL, NULL);
+
+	/* Allocate temporary arrays for new values */
+	values = (Datum *) palloc(nitems * sizeof(Datum));
+	nulls = (bool *) palloc(nitems * sizeof(bool));
+
+	/* Loop over source data */
+	arraydataptr = ARR_DATA_PTR(array);
+	bitmap = ARR_NULLBITMAP(array);
+	bitmask = 1;
+	hasnulls = false;
+	nresult = 0;
+
+	for (i = 0; i < nitems; i++)
+	{
+		Datum		elt;
+		bool		isNull;
+		bool		oprresult;
+		bool		skip = false;
+
+		/* Get source element, checking for NULL */
+		if (bitmap && (*bitmap & bitmask) == 0)
+		{
+			isNull = true;
+			/* If searching for NULL, we have a match */
+			if (search_isnull)
+			{
+				if (remove)
+				{
+					skip = true;
+					changed = true;
+				}
+				else if (!replace_isnull)
+				{
+					values[nresult] = replace;
+					isNull = false;
+					changed = true;
+				}
+			}
+		}
+		else
+		{
+			isNull = false;
+			elt = fetch_att(arraydataptr, typbyval, typlen);
+			arraydataptr = att_addlength_datum(arraydataptr, typlen, elt);
+			arraydataptr = (char *) att_align_nominal(arraydataptr, typalign);
+
+			if (search_isnull)
+			{
+				/* no match possible, keep element */
+				values[nresult] = elt;
+			}
+			else
+			{
+				/*
+				 * Apply the operator to the element pair; treat NULL as false
+				 */
+				locfcinfo->args[0].value = elt;
+				locfcinfo->args[0].isnull = false;
+				locfcinfo->args[1].value = search;
+				locfcinfo->args[1].isnull = false;
+				locfcinfo->isnull = false;
+				oprresult = DatumGetBool(FunctionCallInvoke(locfcinfo));
+				if (locfcinfo->isnull || !oprresult)
+				{
+					/* no match, keep element */
+					values[nresult] = elt;
+				}
+				else
+				{
+					/* match, so replace or delete */
+					changed = true;
+					if (remove)
+						skip = true;
+					else
+					{
+						values[nresult] = replace;
+						isNull = replace_isnull;
+					}
+				}
+			}
+		}
+
+		if (!skip)
+		{
+			nulls[nresult] = isNull;
+			if (isNull)
+				hasnulls = true;
+			else
+			{
+				/* Update total result size */
+				nbytes = att_addlength_datum(nbytes, typlen, values[nresult]);
+				nbytes = att_align_nominal(nbytes, typalign);
+				/* check for overflow of total request */
+				if (!AllocSizeIsValid(nbytes))
+					ereport(ERROR,
+							(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+							 errmsg("array size exceeds the maximum allowed (%d)",
+									(int) MaxAllocSize)));
+			}
+			nresult++;
+		}
+
+		/* advance bitmap pointer if any */
+		if (bitmap)
+		{
+			bitmask <<= 1;
+			if (bitmask == 0x100)
+			{
+				bitmap++;
+				bitmask = 1;
+			}
+		}
+	}
+
+	/*
+	 * If not changed just return the original array
+	 */
+	if (!changed)
+	{
+		pfree(values);
+		pfree(nulls);
+		return array;
+	}
+
+	/* If all elements were removed return an empty array */
+	if (nresult == 0)
+	{
+		pfree(values);
+		pfree(nulls);
+		return construct_empty_array(element_type);
+	}
+
+	/* Allocate and initialize the result array */
+	if (hasnulls)
+	{
+		dataoffset = ARR_OVERHEAD_WITHNULLS(ndim, nresult);
+		nbytes += dataoffset;
+	}
+	else
+	{
+		dataoffset = 0;			/* marker for no null bitmap */
+		nbytes += ARR_OVERHEAD_NONULLS(ndim);
+	}
+	result = (ArrayType *) palloc0(nbytes);
+	SET_VARSIZE(result, nbytes);
+	result->ndim = ndim;
+	result->dataoffset = dataoffset;
+	result->elemtype = element_type;
+	memcpy(ARR_DIMS(result), ARR_DIMS(array), ndim * sizeof(int));
+	memcpy(ARR_LBOUND(result), ARR_LBOUND(array), ndim * sizeof(int));
+
+	if (remove)
+	{
+		/* Adjust the result length */
+		ARR_DIMS(result)[0] = nresult;
+	}
+
+	/* Insert data into result array */
+	CopyArrayEls(result,
+				 values, nulls, nresult,
+				 typlen, typbyval, typalign,
+				 false);
+
+	pfree(values);
+	pfree(nulls);
+
+	return result;
+}
+
+/*
+ * Remove any occurrences of an element from an array
+ *
+ * If used on a multi-dimensional array this will raise an error.
+ */
+Datum
+array_remove(PG_FUNCTION_ARGS)
+{
+	ArrayType  *array;
+	Datum		search = PG_GETARG_DATUM(1);
+	bool		search_isnull = PG_ARGISNULL(1);
+
+	if (PG_ARGISNULL(0))
+		PG_RETURN_NULL();
+	array = PG_GETARG_ARRAYTYPE_P(0);
+
+	array = array_replace_internal(array,
+								   search, search_isnull,
+								   (Datum) 0, true,
+								   true, PG_GET_COLLATION(),
+								   fcinfo);
+	PG_RETURN_ARRAYTYPE_P(array);
+}
+
+/*
+ * Replace any occurrences of an element in an array
+ */
+Datum
+array_replace(PG_FUNCTION_ARGS)
+{
+	ArrayType  *array;
+	Datum		search = PG_GETARG_DATUM(1);
+	bool		search_isnull = PG_ARGISNULL(1);
+	Datum		replace = PG_GETARG_DATUM(2);
+	bool		replace_isnull = PG_ARGISNULL(2);
+
+	if (PG_ARGISNULL(0))
+		PG_RETURN_NULL();
+	array = PG_GETARG_ARRAYTYPE_P(0);
+
+	array = array_replace_internal(array,
+								   search, search_isnull,
+								   replace, replace_isnull,
+								   false, PG_GET_COLLATION(),
+								   fcinfo);
+	PG_RETURN_ARRAYTYPE_P(array);
+}
+
+/*
+ * Implements width_bucket(anyelement, anyarray).
+ *
+ * 'thresholds' is an array containing lower bound values for each bucket;
+ * these must be sorted from smallest to largest, or bogus results will be
+ * produced.  If N thresholds are supplied, the output is from 0 to N:
+ * 0 is for inputs < first threshold, N is for inputs >= last threshold.
+ */
+Datum
+width_bucket_array(PG_FUNCTION_ARGS)
+{
+	Datum		operand = PG_GETARG_DATUM(0);
+	ArrayType  *thresholds = PG_GETARG_ARRAYTYPE_P(1);
+	Oid			collation = PG_GET_COLLATION();
+	Oid			element_type = ARR_ELEMTYPE(thresholds);
+	int			result;
+
+	/* Check input */
+	if (ARR_NDIM(thresholds) > 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("thresholds must be one-dimensional array")));
+
+	if (array_contains_nulls(thresholds))
+		ereport(ERROR,
+				(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+				 errmsg("thresholds array must not contain NULLs")));
+
+	/* We have a dedicated implementation for float8 data */
+	if (element_type == FLOAT8OID)
+		result = width_bucket_array_float8(operand, thresholds);
+	else
+	{
+		TypeCacheEntry *typentry;
+
+		/* Cache information about the input type */
+		typentry = (TypeCacheEntry *) fcinfo->flinfo->fn_extra;
+		if (typentry == NULL ||
+			typentry->type_id != element_type)
+		{
+			typentry = lookup_type_cache(element_type,
+										 TYPECACHE_CMP_PROC_FINFO);
+			if (!OidIsValid(typentry->cmp_proc_finfo.fn_oid))
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+						 errmsg("could not identify a comparison function for type %s",
+								format_type_be(element_type))));
+			fcinfo->flinfo->fn_extra = (void *) typentry;
+		}
+
+		/*
+		 * We have separate implementation paths for fixed- and variable-width
+		 * types, since indexing the array is a lot cheaper in the first case.
+		 */
+		if (typentry->typlen > 0)
+			result = width_bucket_array_fixed(operand, thresholds,
+											  collation, typentry);
+		else
+			result = width_bucket_array_variable(operand, thresholds,
+												 collation, typentry);
+	}
+
+	/* Avoid leaking memory when handed toasted input. */
+	PG_FREE_IF_COPY(thresholds, 1);
+
+	PG_RETURN_INT32(result);
+}
+
+/*
+ * width_bucket_array for float8 data.
+ */
+static int
+width_bucket_array_float8(Datum operand, ArrayType *thresholds)
+{
+	float8		op = DatumGetFloat8(operand);
+	float8	   *thresholds_data;
+	int			left;
+	int			right;
+
+	/*
+	 * Since we know the array contains no NULLs, we can just index it
+	 * directly.
+	 */
+	thresholds_data = (float8 *) ARR_DATA_PTR(thresholds);
+
+	left = 0;
+	right = ArrayGetNItems(ARR_NDIM(thresholds), ARR_DIMS(thresholds));
+
+	/*
+	 * If the probe value is a NaN, it's greater than or equal to all possible
+	 * threshold values (including other NaNs), so we need not search.  Note
+	 * that this would give the same result as searching even if the array
+	 * contains multiple NaNs (as long as they're correctly sorted), since the
+	 * loop logic will find the rightmost of multiple equal threshold values.
+	 */
+	if (isnan(op))
+		return right;
+
+	/* Find the bucket */
+	while (left < right)
+	{
+		int			mid = (left + right) / 2;
+
+		if (isnan(thresholds_data[mid]) || op < thresholds_data[mid])
+			right = mid;
+		else
+			left = mid + 1;
+	}
+
+	return left;
+}
+
+/*
+ * width_bucket_array for generic fixed-width data types.
+ */
+static int
+width_bucket_array_fixed(Datum operand,
+						 ArrayType *thresholds,
+						 Oid collation,
+						 TypeCacheEntry *typentry)
+{
+	LOCAL_FCINFO(locfcinfo, 2);
+	char	   *thresholds_data;
+	int			typlen = typentry->typlen;
+	bool		typbyval = typentry->typbyval;
+	int			left;
+	int			right;
+
+	/*
+	 * Since we know the array contains no NULLs, we can just index it
+	 * directly.
+	 */
+	thresholds_data = (char *) ARR_DATA_PTR(thresholds);
+
+	InitFunctionCallInfoData(*locfcinfo, &typentry->cmp_proc_finfo, 2,
+							 collation, NULL, NULL);
+
+	/* Find the bucket */
+	left = 0;
+	right = ArrayGetNItems(ARR_NDIM(thresholds), ARR_DIMS(thresholds));
+	while (left < right)
+	{
+		int			mid = (left + right) / 2;
+		char	   *ptr;
+		int32		cmpresult;
+
+		ptr = thresholds_data + mid * typlen;
+
+		locfcinfo->args[0].value = operand;
+		locfcinfo->args[0].isnull = false;
+		locfcinfo->args[1].value = fetch_att(ptr, typbyval, typlen);
+		locfcinfo->args[1].isnull = false;
+
+		cmpresult = DatumGetInt32(FunctionCallInvoke(locfcinfo));
+
+		/* We don't expect comparison support functions to return null */
+		Assert(!locfcinfo->isnull);
+
+		if (cmpresult < 0)
+			right = mid;
+		else
+			left = mid + 1;
+	}
+
+	return left;
+}
+
+/*
+ * width_bucket_array for generic variable-width data types.
+ */
+static int
+width_bucket_array_variable(Datum operand,
+							ArrayType *thresholds,
+							Oid collation,
+							TypeCacheEntry *typentry)
+{
+	LOCAL_FCINFO(locfcinfo, 2);
+	char	   *thresholds_data;
+	int			typlen = typentry->typlen;
+	bool		typbyval = typentry->typbyval;
+	char		typalign = typentry->typalign;
+	int			left;
+	int			right;
+
+	thresholds_data = (char *) ARR_DATA_PTR(thresholds);
+
+	InitFunctionCallInfoData(*locfcinfo, &typentry->cmp_proc_finfo, 2,
+							 collation, NULL, NULL);
+
+	/* Find the bucket */
+	left = 0;
+	right = ArrayGetNItems(ARR_NDIM(thresholds), ARR_DIMS(thresholds));
+	while (left < right)
+	{
+		int			mid = (left + right) / 2;
+		char	   *ptr;
+		int			i;
+		int32		cmpresult;
+
+		/* Locate mid'th array element by advancing from left element */
+		ptr = thresholds_data;
+		for (i = left; i < mid; i++)
+		{
+			ptr = att_addlength_pointer(ptr, typlen, ptr);
+			ptr = (char *) att_align_nominal(ptr, typalign);
+		}
+
+		locfcinfo->args[0].value = operand;
+		locfcinfo->args[0].isnull = false;
+		locfcinfo->args[1].value = fetch_att(ptr, typbyval, typlen);
+		locfcinfo->args[1].isnull = false;
+
+		cmpresult = DatumGetInt32(FunctionCallInvoke(locfcinfo));
+
+		/* We don't expect comparison support functions to return null */
+		Assert(!locfcinfo->isnull);
+
+		if (cmpresult < 0)
+			right = mid;
+		else
+		{
+			left = mid + 1;
+
+			/*
+			 * Move the thresholds pointer to match new "left" index, so we
+			 * don't have to seek over those elements again.  This trick
+			 * ensures we do only O(N) array indexing work, not O(N^2).
+			 */
+			ptr = att_addlength_pointer(ptr, typlen, ptr);
+			thresholds_data = (char *) att_align_nominal(ptr, typalign);
+		}
+	}
+
+	return left;
+}
+
+/*
+ * Trim the last N elements from an array by building an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = (ARR_NDIM(v) > 0) ? ARR_DIMS(v)[0] : 0;
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Per spec, throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d",
+						array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, false, sizeof(lowerProvided));
+	memset(upperProvided, false, sizeof(upperProvided));
+	if (ARR_NDIM(v) > 0)
+	{
+		upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+		upperProvided[0] = true;
+	}
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}