From fdf2dbda3f49310b20780ad7b290da935cd2335d Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Sun, 9 Jan 2011 00:39:21 -0500
Subject: [PATCH] Fix assorted corner-case bugs in contrib/intarray.

The array containment operators now behave per mathematical expectation
for empty arrays (ie, an empty array is contained in anything).
Both these operators and the query_int operators now work as expected in
GiST and GIN index searches, rather than having corner cases where the
index searches gave different answers.

Also, fix unexpected failures where the operators would claim that an array
contained nulls, when in fact there was no longer any null present (similar
to bug #5784).  The restriction to not have nulls is still there, as
removing it would take a lot of added code complexity and probably slow
things down significantly.

Also, remove the arbitrary restriction to 1-D arrays; unlike the other
restriction, this was buying us nothing performance-wise.

Assorted cosmetic improvements and marginal performance improvements, too.
---
 contrib/intarray/_int.h             |  80 ++++----
 contrib/intarray/_int_bool.c        | 287 ++++++++--------------------
 contrib/intarray/_int_gin.c         | 120 +++++++-----
 contrib/intarray/_int_gist.c        |  31 ++-
 contrib/intarray/_int_op.c          | 109 +++++------
 contrib/intarray/_int_tool.c        | 115 +++++------
 contrib/intarray/_intbig_gist.c     |  17 +-
 contrib/intarray/uninstall__int.sql |   4 +-
 doc/src/sgml/intarray.sgml          |  27 ++-
 9 files changed, 331 insertions(+), 459 deletions(-)

diff --git a/contrib/intarray/_int.h b/contrib/intarray/_int.h
index dd50b37d2e..11c069890e 100644
--- a/contrib/intarray/_int.h
+++ b/contrib/intarray/_int.h
@@ -9,41 +9,36 @@
 /* number ranges for compression */
 #define MAXNUMRANGE 100
 
-/* dimension of array */
-#define NDIM 1
-
 /* useful macros for accessing int4 arrays */
 #define ARRPTR(x)  ( (int4 *) ARR_DATA_PTR(x) )
 #define ARRNELEMS(x)  ArrayGetNItems(ARR_NDIM(x), ARR_DIMS(x))
 
-/* reject arrays we can't handle; but allow a NULL or empty array */
+/* reject arrays we can't handle; to wit, those containing nulls */
 #define CHECKARRVALID(x) \
 	do { \
-		if (x) { \
-			if (ARR_NDIM(x) != NDIM && ARR_NDIM(x) != 0) \
-				ereport(ERROR, \
-						(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), \
-						 errmsg("array must be one-dimensional"))); \
-			if (ARR_HASNULL(x)) \
-				ereport(ERROR, \
-						(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), \
-						 errmsg("array must not contain nulls"))); \
-		} \
+		if (ARR_HASNULL(x) && array_contains_nulls(x)) \
+			ereport(ERROR, \
+					(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), \
+					 errmsg("array must not contain nulls"))); \
 	} while(0)
 
-#define ARRISVOID(x)  ((x) == NULL || ARRNELEMS(x) == 0)
+#define ARRISEMPTY(x)  (ARRNELEMS(x) == 0)
 
+/* sort the elements of the array */
 #define SORT(x) \
 	do { \
-		 if ( ARRNELEMS( x ) > 1 ) \
-			isort( ARRPTR( x ), ARRNELEMS( x ) ); \
+		int		_nelems_ = ARRNELEMS(x); \
+		if (_nelems_ > 1) \
+			isort(ARRPTR(x), _nelems_); \
 	} while(0)
 
+/* sort the elements of the array and remove duplicates */
 #define PREPAREARR(x) \
 	do { \
-		 if ( ARRNELEMS( x ) > 1 ) \
-			if ( isort( ARRPTR( x ), ARRNELEMS( x ) ) ) \
-				x = _int_unique( x ); \
+		int		_nelems_ = ARRNELEMS(x); \
+		if (_nelems_ > 1) \
+			if (isort(ARRPTR(x), _nelems_)) \
+				(x) = _int_unique(x); \
 	} while(0)
 
 /* "wish" function */
@@ -90,14 +85,14 @@ typedef struct
 #define GETSIGN(x)		( (BITVECP)( (char*)x+GTHDRSIZE ) )
 
 /*
-** types for functions
-*/
+ * types for functions
+ */
 typedef ArrayType *(*formarray) (ArrayType *, ArrayType *);
 typedef void (*formfloat) (ArrayType *, float *);
 
 /*
-** useful function
-*/
+ * useful functions
+ */
 bool		isort(int4 *a, int len);
 ArrayType  *new_intArrayType(int num);
 ArrayType  *copy_intArrayType(ArrayType *a);
@@ -133,17 +128,18 @@ typedef struct ITEM
 	int4		val;
 } ITEM;
 
-typedef struct
+typedef struct QUERYTYPE
 {
 	int32		vl_len_;		/* varlena header (do not touch directly!) */
-	int4		size;
-	char		data[1];
+	int4		size;			/* number of ITEMs */
+	ITEM		items[1];		/* variable length array */
 } QUERYTYPE;
 
-#define HDRSIZEQT	(VARHDRSZ + sizeof(int4))
-#define COMPUTESIZE(size)	( HDRSIZEQT + size * sizeof(ITEM) )
-#define GETQUERY(x)  (ITEM*)( (char*)(x)+HDRSIZEQT )
+#define HDRSIZEQT	offsetof(QUERYTYPE, items)
+#define COMPUTESIZE(size)	( HDRSIZEQT + (size) * sizeof(ITEM) )
+#define GETQUERY(x)  ( (x)->items )
 
+/* "type" codes for ITEM */
 #define END		0
 #define ERR		1
 #define VAL		2
@@ -151,18 +147,28 @@ typedef struct
 #define OPEN	4
 #define CLOSE	5
 
+/* fmgr macros for QUERYTYPE objects */
+#define DatumGetQueryTypeP(X)		  ((QUERYTYPE *) PG_DETOAST_DATUM(X))
+#define DatumGetQueryTypePCopy(X)	  ((QUERYTYPE *) PG_DETOAST_DATUM_COPY(X))
+#define PG_GETARG_QUERYTYPE_P(n)	  DatumGetQueryTypeP(PG_GETARG_DATUM(n))
+#define PG_GETARG_QUERYTYPE_P_COPY(n) DatumGetQueryTypePCopy(PG_GETARG_DATUM(n))
+
 bool		signconsistent(QUERYTYPE *query, BITVEC sign, bool calcnot);
 bool		execconsistent(QUERYTYPE *query, ArrayType *array, bool calcnot);
-bool		ginconsistent(QUERYTYPE *query, bool *check);
-int4		shorterquery(ITEM *q, int4 len);
+
+bool		gin_bool_consistent(QUERYTYPE *query, bool *check);
+bool		query_has_required_values(QUERYTYPE *query);
 
 int			compASC(const void *a, const void *b);
-
 int			compDESC(const void *a, const void *b);
 
-#define QSORT(a, direction)										\
-if (ARRNELEMS(a) > 1)											\
-		qsort((void*)ARRPTR(a), ARRNELEMS(a),sizeof(int4),		\
-				(direction) ? compASC : compDESC )
+/* sort, either ascending or descending */
+#define QSORT(a, direction) \
+	do { \
+		int		_nelems_ = ARRNELEMS(a); \
+		if (_nelems_ > 1) \
+			qsort((void*) ARRPTR(a), _nelems_, sizeof(int4), \
+				  (direction) ? compASC : compDESC ); \
+	} while(0)
 
 #endif   /* ___INT_H__ */
diff --git a/contrib/intarray/_int_bool.c b/contrib/intarray/_int_bool.c
index 4cc447bab2..3492100c0c 100644
--- a/contrib/intarray/_int_bool.c
+++ b/contrib/intarray/_int_bool.c
@@ -3,6 +3,7 @@
  */
 #include "postgres.h"
 
+#include "miscadmin.h"
 #include "utils/builtins.h"
 
 #include "_int.h"
@@ -22,13 +23,6 @@ PG_FUNCTION_INFO_V1(querytree);
 Datum		querytree(PG_FUNCTION_ARGS);
 
 
-#define END		0
-#define ERR		1
-#define VAL		2
-#define OPR		3
-#define OPEN	4
-#define CLOSE	5
-
 /* parser's states */
 #define WAITOPERAND 1
 #define WAITENDOPERAND	2
@@ -167,6 +161,9 @@ makepol(WORKSTATE *state)
 	int4		stack[STACKDEPTH];
 	int4		lenstack = 0;
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	while ((type = gettoken(state, &val)) != END)
 	{
 		switch (type)
@@ -236,7 +233,7 @@ typedef struct
 } CHKVAL;
 
 /*
- * is there value 'val' in array or not ?
+ * is there value 'val' in (sorted) array or not ?
  */
 static bool
 checkcondition_arr(void *checkval, ITEM *item)
@@ -267,11 +264,14 @@ checkcondition_bit(void *checkval, ITEM *item)
 }
 
 /*
- * check for boolean condition
+ * evaluate boolean expression, using chkcond() to test the primitive cases
  */
 static bool
-execute(ITEM *curitem, void *checkval, bool calcnot, bool (*chkcond) (void *checkval, ITEM *item))
+execute(ITEM *curitem, void *checkval, bool calcnot,
+		bool (*chkcond) (void *checkval, ITEM *item))
 {
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
 
 	if (curitem->type == VAL)
 		return (*chkcond) (checkval, curitem);
@@ -304,13 +304,12 @@ execute(ITEM *curitem, void *checkval, bool calcnot, bool (*chkcond) (void *chec
 bool
 signconsistent(QUERYTYPE *query, BITVEC sign, bool calcnot)
 {
-	return execute(
-				   GETQUERY(query) + query->size - 1,
+	return execute(GETQUERY(query) + query->size - 1,
 				   (void *) sign, calcnot,
-				   checkcondition_bit
-		);
+				   checkcondition_bit);
 }
 
+/* Array must be sorted! */
 bool
 execconsistent(QUERYTYPE *query, ArrayType *array, bool calcnot)
 {
@@ -319,11 +318,9 @@ execconsistent(QUERYTYPE *query, ArrayType *array, bool calcnot)
 	CHECKARRVALID(array);
 	chkval.arrb = ARRPTR(array);
 	chkval.arre = chkval.arrb + ARRNELEMS(array);
-	return execute(
-				   GETQUERY(query) + query->size - 1,
+	return execute(GETQUERY(query) + query->size - 1,
 				   (void *) &chkval, calcnot,
-				   checkcondition_arr
-		);
+				   checkcondition_arr);
 }
 
 typedef struct
@@ -341,27 +338,75 @@ checkcondition_gin(void *checkval, ITEM *item)
 }
 
 bool
-ginconsistent(QUERYTYPE *query, bool *check)
+gin_bool_consistent(QUERYTYPE *query, bool *check)
 {
 	GinChkVal	gcv;
 	ITEM	   *items = GETQUERY(query);
 	int			i,
 				j = 0;
 
-	if (query->size < 0)
+	if (query->size <= 0)
 		return FALSE;
 
+	/*
+	 * Set up data for checkcondition_gin.  This must agree with the
+	 * query extraction code in ginint4_queryextract.
+	 */
 	gcv.first = items;
 	gcv.mapped_check = (bool *) palloc(sizeof(bool) * query->size);
 	for (i = 0; i < query->size; i++)
+	{
 		if (items[i].type == VAL)
 			gcv.mapped_check[i] = check[j++];
+	}
 
-	return execute(
-				   GETQUERY(query) + query->size - 1,
+	return execute(GETQUERY(query) + query->size - 1,
 				   (void *) &gcv, true,
-				   checkcondition_gin
-		);
+				   checkcondition_gin);
+}
+
+static bool
+contains_required_value(ITEM *curitem)
+{
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
+	if (curitem->type == VAL)
+		return true;
+	else if (curitem->val == (int4) '!')
+	{
+		/*
+		 * Assume anything under a NOT is non-required.  For some cases with
+		 * nested NOTs, we could prove there's a required value, but it seems
+		 * unlikely to be worth the trouble.
+		 */
+		return false;
+	}
+	else if (curitem->val == (int4) '&')
+	{
+		/* If either side has a required value, we're good */
+		if (contains_required_value(curitem + curitem->left))
+			return true;
+		else
+			return contains_required_value(curitem - 1);
+	}
+	else
+	{							/* |-operator */
+		/* Both sides must have required values */
+		if (contains_required_value(curitem + curitem->left))
+			return contains_required_value(curitem - 1);
+		else
+			return false;
+	}
+	return false;
+}
+
+bool
+query_has_required_values(QUERYTYPE *query)
+{
+	if (query->size <= 0)
+		return false;
+	return contains_required_value(GETQUERY(query) + query->size - 1);
 }
 
 /*
@@ -370,37 +415,27 @@ ginconsistent(QUERYTYPE *query, bool *check)
 Datum
 rboolop(PG_FUNCTION_ARGS)
 {
-	return DirectFunctionCall2(
-							   boolop,
+	/* just reverse the operands */
+	return DirectFunctionCall2(boolop,
 							   PG_GETARG_DATUM(1),
-							   PG_GETARG_DATUM(0)
-		);
+							   PG_GETARG_DATUM(0));
 }
 
 Datum
 boolop(PG_FUNCTION_ARGS)
 {
-	ArrayType  *val = (ArrayType *) PG_DETOAST_DATUM_COPY(PG_GETARG_POINTER(0));
-	QUERYTYPE  *query = (QUERYTYPE *) PG_DETOAST_DATUM(PG_GETARG_POINTER(1));
+	ArrayType  *val = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	QUERYTYPE  *query = PG_GETARG_QUERYTYPE_P(1);
 	CHKVAL		chkval;
 	bool		result;
 
 	CHECKARRVALID(val);
-	if (ARRISVOID(val))
-	{
-		pfree(val);
-		PG_FREE_IF_COPY(query, 1);
-		PG_RETURN_BOOL(false);
-	}
-
 	PREPAREARR(val);
 	chkval.arrb = ARRPTR(val);
 	chkval.arre = chkval.arrb + ARRNELEMS(val);
-	result = execute(
-					 GETQUERY(query) + query->size - 1,
+	result = execute(GETQUERY(query) + query->size - 1,
 					 &chkval, true,
-					 checkcondition_arr
-		);
+					 checkcondition_arr);
 	pfree(val);
 
 	PG_FREE_IF_COPY(query, 1);
@@ -599,7 +634,7 @@ infix(INFIX *in, bool first)
 Datum
 bqarr_out(PG_FUNCTION_ARGS)
 {
-	QUERYTYPE  *query = (QUERYTYPE *) PG_DETOAST_DATUM(PG_GETARG_POINTER(0));
+	QUERYTYPE  *query = PG_GETARG_QUERYTYPE_P(0);
 	INFIX		nrm;
 
 	if (query->size == 0)
@@ -617,173 +652,11 @@ bqarr_out(PG_FUNCTION_ARGS)
 	PG_RETURN_POINTER(nrm.buf);
 }
 
-static int4
-countdroptree(ITEM *q, int4 pos)
-{
-	if (q[pos].type == VAL)
-		return 1;
-	else if (q[pos].val == (int4) '!')
-		return 1 + countdroptree(q, pos - 1);
-	else
-		return 1 + countdroptree(q, pos - 1) + countdroptree(q, pos + q[pos].left);
-}
-
-/*
- * common algorithm:
- * result of all '!' will be = 'true', so
- * we can modify query tree for clearing
- */
-int4
-shorterquery(ITEM *q, int4 len)
-{
-	int4		index,
-				posnot,
-				poscor;
-	bool		notisleft = false;
-	int4		drop,
-				i;
-
-	/* out all '!' */
-	do
-	{
-		index = 0;
-		drop = 0;
-		/* find ! */
-		for (posnot = 0; posnot < len; posnot++)
-			if (q[posnot].type == OPR && q[posnot].val == (int4) '!')
-			{
-				index = 1;
-				break;
-			}
-
-		if (posnot == len)
-			return len;
-
-		/* last operator is ! */
-		if (posnot == len - 1)
-			return 0;
-
-		/* find operator for this operand */
-		for (poscor = posnot + 1; poscor < len; poscor++)
-		{
-			if (q[poscor].type == OPR)
-			{
-				if (poscor == posnot + 1)
-				{
-					notisleft = false;
-					break;
-				}
-				else if (q[poscor].left + poscor == posnot)
-				{
-					notisleft = true;
-					break;
-				}
-			}
-		}
-		if (q[poscor].val == (int4) '!')
-		{
-			drop = countdroptree(q, poscor);
-			q[poscor - 1].type = VAL;
-			for (i = poscor + 1; i < len; i++)
-				if (q[i].type == OPR && q[i].left + i <= poscor)
-					q[i].left += drop - 2;
-			memcpy((void *) &q[poscor - drop + 1],
-				   (void *) &q[poscor - 1],
-				   sizeof(ITEM) * (len - (poscor - 1)));
-			len -= drop - 2;
-		}
-		else if (q[poscor].val == (int4) '|')
-		{
-			drop = countdroptree(q, poscor);
-			q[poscor - 1].type = VAL;
-			q[poscor].val = (int4) '!';
-			q[poscor].left = -1;
-			for (i = poscor + 1; i < len; i++)
-				if (q[i].type == OPR && q[i].left + i < poscor)
-					q[i].left += drop - 2;
-			memcpy((void *) &q[poscor - drop + 1],
-				   (void *) &q[poscor - 1],
-				   sizeof(ITEM) * (len - (poscor - 1)));
-			len -= drop - 2;
-		}
-		else
-		{						/* &-operator */
-			if (
-				(notisleft && q[poscor - 1].type == OPR &&
-				 q[poscor - 1].val == (int4) '!') ||
-				(!notisleft && q[poscor + q[poscor].left].type == OPR &&
-				 q[poscor + q[poscor].left].val == (int4) '!')
-				)
-			{					/* drop subtree */
-				drop = countdroptree(q, poscor);
-				q[poscor - 1].type = VAL;
-				q[poscor].val = (int4) '!';
-				q[poscor].left = -1;
-				for (i = poscor + 1; i < len; i++)
-					if (q[i].type == OPR && q[i].left + i < poscor)
-						q[i].left += drop - 2;
-				memcpy((void *) &q[poscor - drop + 1],
-					   (void *) &q[poscor - 1],
-					   sizeof(ITEM) * (len - (poscor - 1)));
-				len -= drop - 2;
-			}
-			else
-			{					/* drop only operator */
-				int4		subtreepos = (notisleft) ?
-				poscor - 1 : poscor + q[poscor].left;
-				int4		subtreelen = countdroptree(q, subtreepos);
-
-				drop = countdroptree(q, poscor);
-				for (i = poscor + 1; i < len; i++)
-					if (q[i].type == OPR && q[i].left + i < poscor)
-						q[i].left += drop - subtreelen;
-				memcpy((void *) &q[subtreepos + 1],
-					   (void *) &q[poscor + 1],
-					   sizeof(ITEM) * (len - (poscor - 1)));
-				memcpy((void *) &q[poscor - drop + 1],
-					   (void *) &q[subtreepos - subtreelen + 1],
-					   sizeof(ITEM) * (len - (drop - subtreelen)));
-				len -= drop - subtreelen;
-			}
-		}
-	} while (index);
-	return len;
-}
-
 
+/* Useless old "debugging" function for a fundamentally wrong algorithm */
 Datum
 querytree(PG_FUNCTION_ARGS)
 {
-	QUERYTYPE  *query = (QUERYTYPE *) PG_DETOAST_DATUM(PG_GETARG_POINTER(0));
-	INFIX		nrm;
-	text	   *res;
-	ITEM	   *q;
-	int4		len;
-
-	if (query->size == 0)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("empty query")));
-
-	q = (ITEM *) palloc(sizeof(ITEM) * query->size);
-	memcpy((void *) q, GETQUERY(query), sizeof(ITEM) * query->size);
-	len = shorterquery(q, query->size);
-	PG_FREE_IF_COPY(query, 0);
-
-	if (len == 0)
-	{
-		res = cstring_to_text("T");
-	}
-	else
-	{
-		nrm.curpol = q + len - 1;
-		nrm.buflen = 32;
-		nrm.cur = nrm.buf = (char *) palloc(sizeof(char) * nrm.buflen);
-		*(nrm.cur) = '\0';
-		infix(&nrm, true);
-		res = cstring_to_text_with_len(nrm.buf, nrm.cur - nrm.buf);
-	}
-	pfree(q);
-
-	PG_RETURN_TEXT_P(res);
+	elog(ERROR, "querytree is no longer implemented");
+	PG_RETURN_NULL();
 }
diff --git a/contrib/intarray/_int_gin.c b/contrib/intarray/_int_gin.c
index b5ad69eba3..3ef5c4635a 100644
--- a/contrib/intarray/_int_gin.c
+++ b/contrib/intarray/_int_gin.c
@@ -3,6 +3,7 @@
  */
 #include "postgres.h"
 
+#include "access/gin.h"
 #include "access/gist.h"
 #include "access/skey.h"
 
@@ -16,66 +17,90 @@ ginint4_queryextract(PG_FUNCTION_ARGS)
 {
 	int32	   *nentries = (int32 *) PG_GETARG_POINTER(1);
 	StrategyNumber strategy = PG_GETARG_UINT16(2);
+	int32	   *searchMode = (int32 *) PG_GETARG_POINTER(6);
 	Datum	   *res = NULL;
 
 	*nentries = 0;
 
 	if (strategy == BooleanSearchStrategy)
 	{
-		QUERYTYPE  *query = (QUERYTYPE *) PG_DETOAST_DATUM_COPY(PG_GETARG_POINTER(0));
+		QUERYTYPE  *query = PG_GETARG_QUERYTYPE_P(0);
 		ITEM	   *items = GETQUERY(query);
 		int			i;
 
-		if (query->size == 0)
+		/* empty query must fail */
+		if (query->size <= 0)
 			PG_RETURN_POINTER(NULL);
 
-		if (shorterquery(items, query->size) == 0)
-			elog(ERROR, "Query requires full scan, GIN doesn't support it");
-
-		pfree(query);
-
-		query = (QUERYTYPE *) PG_DETOAST_DATUM(PG_GETARG_POINTER(0));
-		items = GETQUERY(query);
+		/*
+		 * If the query doesn't have any required primitive values (for
+		 * instance, it's something like '! 42'), we have to do a full
+		 * index scan.
+		 */
+		if (query_has_required_values(query))
+			*searchMode = GIN_SEARCH_MODE_DEFAULT;
+		else
+			*searchMode = GIN_SEARCH_MODE_ALL;
 
+		/*
+		 * Extract all the VAL items as things we want GIN to check for.
+		 */
 		res = (Datum *) palloc(sizeof(Datum) * query->size);
 		*nentries = 0;
 
 		for (i = 0; i < query->size; i++)
+		{
 			if (items[i].type == VAL)
 			{
 				res[*nentries] = Int32GetDatum(items[i].val);
 				(*nentries)++;
 			}
+		}
 	}
 	else
 	{
 		ArrayType  *query = PG_GETARG_ARRAYTYPE_P(0);
-		int4	   *arr;
-		uint32		i;
 
 		CHECKARRVALID(query);
 		*nentries = ARRNELEMS(query);
 		if (*nentries > 0)
 		{
+			int4	   *arr;
+			int32		i;
+
 			res = (Datum *) palloc(sizeof(Datum) * (*nentries));
 
 			arr = ARRPTR(query);
 			for (i = 0; i < *nentries; i++)
 				res[i] = Int32GetDatum(arr[i]);
 		}
-	}
 
-	if (*nentries == 0)
-	{
 		switch (strategy)
 		{
-			case BooleanSearchStrategy:
 			case RTOverlapStrategyNumber:
-				*nentries = -1; /* nobody can be found */
+				*searchMode = GIN_SEARCH_MODE_DEFAULT;
 				break;
-			default:			/* require fullscan: GIN can't find void
-								 * arrays */
+			case RTContainedByStrategyNumber:
+			case RTOldContainedByStrategyNumber:
+				/* empty set is contained in everything */
+				*searchMode = GIN_SEARCH_MODE_INCLUDE_EMPTY;
 				break;
+			case RTSameStrategyNumber:
+				if (*nentries > 0)
+					*searchMode = GIN_SEARCH_MODE_DEFAULT;
+				else
+					*searchMode = GIN_SEARCH_MODE_INCLUDE_EMPTY;
+				break;
+			case RTContainsStrategyNumber:
+			case RTOldContainsStrategyNumber:
+				if (*nentries > 0)
+					*searchMode = GIN_SEARCH_MODE_DEFAULT;
+				else				/* everything contains the empty set */
+					*searchMode = GIN_SEARCH_MODE_ALL;
+				break;
+			default:
+				elog(ERROR, "ginint4_queryextract: unknown strategy number: %d",
+					 strategy);
 		}
 	}
 
@@ -90,16 +115,11 @@ ginint4_consistent(PG_FUNCTION_ARGS)
 {
 	bool	   *check = (bool *) PG_GETARG_POINTER(0);
 	StrategyNumber strategy = PG_GETARG_UINT16(1);
-
-	/* int32	nkeys = PG_GETARG_INT32(3); */
+	int32		nkeys = PG_GETARG_INT32(3);
 	/* Pointer	   *extra_data = (Pointer *) PG_GETARG_POINTER(4); */
 	bool	   *recheck = (bool *) PG_GETARG_POINTER(5);
 	bool		res = FALSE;
-
-	/*
-	 * we need not check array carefully, it's done by previous
-	 * ginarrayextract call
-	 */
+	int32		i;
 
 	switch (strategy)
 	{
@@ -117,47 +137,41 @@ ginint4_consistent(PG_FUNCTION_ARGS)
 			res = TRUE;
 			break;
 		case RTSameStrategyNumber:
+			/* we will need recheck */
+			*recheck = true;
+			/* Must have all elements in check[] true */
+			res = TRUE;
+			for (i = 0; i < nkeys; i++)
 			{
-				ArrayType  *query = PG_GETARG_ARRAYTYPE_P(2);
-				int			i,
-							nentries = ARRNELEMS(query);
-
-				/* we will need recheck */
-				*recheck = true;
-				res = TRUE;
-				for (i = 0; i < nentries; i++)
-					if (!check[i])
-					{
-						res = FALSE;
-						break;
-					}
+				if (!check[i])
+				{
+					res = FALSE;
+					break;
+				}
 			}
 			break;
 		case RTContainsStrategyNumber:
 		case RTOldContainsStrategyNumber:
+			/* result is not lossy */
+			*recheck = false;
+			/* Must have all elements in check[] true */
+			res = TRUE;
+			for (i = 0; i < nkeys; i++)
 			{
-				ArrayType  *query = PG_GETARG_ARRAYTYPE_P(2);
-				int			i,
-							nentries = ARRNELEMS(query);
-
-				/* result is not lossy */
-				*recheck = false;
-				res = TRUE;
-				for (i = 0; i < nentries; i++)
-					if (!check[i])
-					{
-						res = FALSE;
-						break;
-					}
+				if (!check[i])
+				{
+					res = FALSE;
+					break;
+				}
 			}
 			break;
 		case BooleanSearchStrategy:
 			{
-				QUERYTYPE  *query = (QUERYTYPE *) PG_DETOAST_DATUM(PG_GETARG_POINTER(2));
+				QUERYTYPE  *query = PG_GETARG_QUERYTYPE_P(2);
 
 				/* result is not lossy */
 				*recheck = false;
-				res = ginconsistent(query, check);
+				res = gin_bool_consistent(query, check);
 			}
 			break;
 		default:
diff --git a/contrib/intarray/_int_gist.c b/contrib/intarray/_int_gist.c
index 65c9bf2e74..0a173bfcb6 100644
--- a/contrib/intarray/_int_gist.c
+++ b/contrib/intarray/_int_gist.c
@@ -40,7 +40,7 @@ Datum
 g_int_consistent(PG_FUNCTION_ARGS)
 {
 	GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
-	ArrayType  *query = (ArrayType *) PG_DETOAST_DATUM_COPY(PG_GETARG_POINTER(1));
+	ArrayType  *query = PG_GETARG_ARRAYTYPE_P_COPY(1);
 	StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
 
 	/* Oid		subtype = PG_GETARG_OID(3); */
@@ -62,11 +62,6 @@ g_int_consistent(PG_FUNCTION_ARGS)
 
 	/* sort query for fast search, key is already sorted */
 	CHECKARRVALID(query);
-	if (ARRISVOID(query))
-	{
-		pfree(query);
-		PG_RETURN_BOOL(false);
-	}
 	PREPAREARR(query);
 
 	switch (strategy)
@@ -77,12 +72,10 @@ g_int_consistent(PG_FUNCTION_ARGS)
 			break;
 		case RTSameStrategyNumber:
 			if (GIST_LEAF(entry))
-				DirectFunctionCall3(
-									g_int_same,
+				DirectFunctionCall3(g_int_same,
 									entry->key,
 									PointerGetDatum(query),
-									PointerGetDatum(&retval)
-					);
+									PointerGetDatum(&retval));
 			else
 				retval = inner_int_contains((ArrayType *) DatumGetPointer(entry->key),
 											query);
@@ -162,7 +155,7 @@ g_int_compress(PG_FUNCTION_ARGS)
 
 	if (entry->leafkey)
 	{
-		r = (ArrayType *) PG_DETOAST_DATUM_COPY(entry->key);
+		r = DatumGetArrayTypePCopy(entry->key);
 		CHECKARRVALID(r);
 		PREPAREARR(r);
 
@@ -182,9 +175,9 @@ g_int_compress(PG_FUNCTION_ARGS)
 	 * ==true, so now we work only with internal keys
 	 */
 
-	r = (ArrayType *) PG_DETOAST_DATUM(entry->key);
+	r = DatumGetArrayTypeP(entry->key);
 	CHECKARRVALID(r);
-	if (ARRISVOID(r))
+	if (ARRISEMPTY(r))
 	{
 		if (r != (ArrayType *) DatumGetPointer(entry->key))
 			pfree(r);
@@ -194,7 +187,7 @@ g_int_compress(PG_FUNCTION_ARGS)
 	if ((len = ARRNELEMS(r)) >= 2 * MAXNUMRANGE)
 	{							/* compress */
 		if (r == (ArrayType *) DatumGetPointer(entry->key))
-			r = (ArrayType *) PG_DETOAST_DATUM_COPY(entry->key);
+			r = DatumGetArrayTypePCopy(entry->key);
 		r = resize_intArrayType(r, 2 * (len));
 
 		dr = ARRPTR(r);
@@ -242,10 +235,10 @@ g_int_decompress(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 
-	in = (ArrayType *) PG_DETOAST_DATUM(entry->key);
+	in = DatumGetArrayTypeP(entry->key);
 
 	CHECKARRVALID(in);
-	if (ARRISVOID(in))
+	if (ARRISEMPTY(in))
 	{
 		if (in != (ArrayType *) DatumGetPointer(entry->key))
 		{
@@ -321,8 +314,8 @@ g_int_penalty(PG_FUNCTION_ARGS)
 Datum
 g_int_same(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) PointerGetDatum(PG_GETARG_POINTER(0));
-	ArrayType  *b = (ArrayType *) PointerGetDatum(PG_GETARG_POINTER(1));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P(1);
 	bool	   *result = (bool *) PG_GETARG_POINTER(2);
 	int4		n = ARRNELEMS(a);
 	int4	   *da,
@@ -340,11 +333,13 @@ g_int_same(PG_FUNCTION_ARGS)
 	da = ARRPTR(a);
 	db = ARRPTR(b);
 	while (n--)
+	{
 		if (*da++ != *db++)
 		{
 			*result = FALSE;
 			break;
 		}
+	}
 
 	PG_RETURN_POINTER(result);
 }
diff --git a/contrib/intarray/_int_op.c b/contrib/intarray/_int_op.c
index 1d99c6905e..392e227cff 100644
--- a/contrib/intarray/_int_op.c
+++ b/contrib/intarray/_int_op.c
@@ -29,27 +29,22 @@ Datum		_int_inter(PG_FUNCTION_ARGS);
 Datum
 _int_contained(PG_FUNCTION_ARGS)
 {
-	PG_RETURN_BOOL(DatumGetBool(
-								DirectFunctionCall2(
-													_int_contains,
-									   PointerGetDatum(PG_GETARG_POINTER(1)),
-										PointerGetDatum(PG_GETARG_POINTER(0))
-													)
-								));
+	/* just reverse the operands and call _int_contains */
+	return DirectFunctionCall2(_int_contains,
+							   PG_GETARG_DATUM(1),
+							   PG_GETARG_DATUM(0));
 }
 
 Datum
 _int_contains(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
-	ArrayType  *b = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(1)));
+	/* Force copy so we can modify the arrays in-place */
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P_COPY(1);
 	bool		res;
 
 	CHECKARRVALID(a);
 	CHECKARRVALID(b);
-	if (ARRISVOID(a) || ARRISVOID(b))
-		return FALSE;
-
 	PREPAREARR(a);
 	PREPAREARR(b);
 	res = inner_int_contains(a, b);
@@ -73,24 +68,17 @@ _int_different(PG_FUNCTION_ARGS)
 Datum
 _int_same(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
-	ArrayType  *b = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(1)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P_COPY(1);
 	int			na,
 				nb;
 	int			n;
 	int		   *da,
 			   *db;
 	bool		result;
-	bool		avoid;
-	bool		bvoid;
 
 	CHECKARRVALID(a);
 	CHECKARRVALID(b);
-	avoid = ARRISVOID(a);
-	bvoid = ARRISVOID(b);
-	if (avoid || bvoid)
-		return (avoid && bvoid) ? TRUE : FALSE;
-
 	na = ARRNELEMS(a);
 	nb = ARRNELEMS(b);
 	da = ARRPTR(a);
@@ -105,11 +93,13 @@ _int_same(PG_FUNCTION_ARGS)
 		result = TRUE;
 
 		for (n = 0; n < na; n++)
+		{
 			if (da[n] != db[n])
 			{
 				result = FALSE;
 				break;
 			}
+		}
 	}
 
 	pfree(a);
@@ -123,13 +113,13 @@ _int_same(PG_FUNCTION_ARGS)
 Datum
 _int_overlap(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
-	ArrayType  *b = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(1)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P_COPY(1);
 	bool		result;
 
 	CHECKARRVALID(a);
 	CHECKARRVALID(b);
-	if (ARRISVOID(a) || ARRISVOID(b))
+	if (ARRISEMPTY(a) || ARRISEMPTY(b))
 		return FALSE;
 
 	SORT(a);
@@ -146,24 +136,20 @@ _int_overlap(PG_FUNCTION_ARGS)
 Datum
 _int_union(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
-	ArrayType  *b = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(1)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P_COPY(1);
 	ArrayType  *result;
 
 	CHECKARRVALID(a);
 	CHECKARRVALID(b);
 
-	if (!ARRISVOID(a))
-		SORT(a);
-	if (!ARRISVOID(b))
-		SORT(b);
+	SORT(a);
+	SORT(b);
 
 	result = inner_int_union(a, b);
 
-	if (a)
-		pfree(a);
-	if (b)
-		pfree(b);
+	pfree(a);
+	pfree(b);
 
 	PG_RETURN_POINTER(result);
 }
@@ -171,14 +157,12 @@ _int_union(PG_FUNCTION_ARGS)
 Datum
 _int_inter(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
-	ArrayType  *b = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(1)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P_COPY(1);
 	ArrayType  *result;
 
 	CHECKARRVALID(a);
 	CHECKARRVALID(b);
-	if (ARRISVOID(a) || ARRISVOID(b))
-		PG_RETURN_POINTER(new_intArrayType(0));
 
 	SORT(a);
 	SORT(b);
@@ -228,7 +212,7 @@ intset(PG_FUNCTION_ARGS)
 Datum
 icount(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
 	int32		count = ARRNELEMS(a);
 
 	PG_FREE_IF_COPY(a, 0);
@@ -238,14 +222,14 @@ icount(PG_FUNCTION_ARGS)
 Datum
 sort(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
 	text	   *dirstr = (fcinfo->nargs == 2) ? PG_GETARG_TEXT_P(1) : NULL;
 	int32		dc = (dirstr) ? VARSIZE(dirstr) - VARHDRSZ : 0;
 	char	   *d = (dirstr) ? VARDATA(dirstr) : NULL;
 	int			dir = -1;
 
 	CHECKARRVALID(a);
-	if (ARRISVOID(a) || ARRNELEMS(a) < 2)
+	if (ARRNELEMS(a) < 2)
 		PG_RETURN_POINTER(a);
 
 	if (dirstr == NULL || (dc == 3
@@ -270,11 +254,9 @@ sort(PG_FUNCTION_ARGS)
 Datum
 sort_asc(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
 
 	CHECKARRVALID(a);
-	if (ARRISVOID(a))
-		PG_RETURN_POINTER(a);
 	QSORT(a, 1);
 	PG_RETURN_POINTER(a);
 }
@@ -282,11 +264,9 @@ sort_asc(PG_FUNCTION_ARGS)
 Datum
 sort_desc(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
 
 	CHECKARRVALID(a);
-	if (ARRISVOID(a))
-		PG_RETURN_POINTER(a);
 	QSORT(a, 0);
 	PG_RETURN_POINTER(a);
 }
@@ -294,10 +274,10 @@ sort_desc(PG_FUNCTION_ARGS)
 Datum
 uniq(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
 
 	CHECKARRVALID(a);
-	if (ARRISVOID(a) || ARRNELEMS(a) < 2)
+	if (ARRNELEMS(a) < 2)
 		PG_RETURN_POINTER(a);
 	a = _int_unique(a);
 	PG_RETURN_POINTER(a);
@@ -306,11 +286,11 @@ uniq(PG_FUNCTION_ARGS)
 Datum
 idx(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
 	int32		result;
 
 	CHECKARRVALID(a);
-	result = (ARRISVOID(a)) ? 0 : ARRNELEMS(a);
+	result = ARRNELEMS(a);
 	if (result)
 		result = intarray_match_first(a, PG_GETARG_INT32(1));
 	PG_FREE_IF_COPY(a, 0);
@@ -320,15 +300,17 @@ idx(PG_FUNCTION_ARGS)
 Datum
 subarray(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
-	ArrayType  *result;
-	int32		start = (PG_GETARG_INT32(1) > 0) ? PG_GETARG_INT32(1) - 1 : PG_GETARG_INT32(1);
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
+	int32		start = PG_GETARG_INT32(1);
 	int32		len = (fcinfo->nargs == 3) ? PG_GETARG_INT32(2) : 0;
 	int32		end = 0;
 	int32		c;
+	ArrayType  *result;
+
+	start = (start > 0) ? start - 1 : start;
 
 	CHECKARRVALID(a);
-	if (ARRISVOID(a))
+	if (ARRISEMPTY(a))
 	{
 		PG_FREE_IF_COPY(a, 0);
 		PG_RETURN_POINTER(new_intArrayType(0));
@@ -358,7 +340,6 @@ subarray(PG_FUNCTION_ARGS)
 		PG_RETURN_POINTER(new_intArrayType(0));
 	}
 
-
 	result = new_intArrayType(end - start);
 	if (end - start > 0)
 		memcpy(ARRPTR(result), ARRPTR(a) + start, (end - start) * sizeof(int32));
@@ -369,7 +350,7 @@ subarray(PG_FUNCTION_ARGS)
 Datum
 intarray_push_elem(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
 	ArrayType  *result;
 
 	result = intarray_add_elem(a, PG_GETARG_INT32(1));
@@ -380,8 +361,8 @@ intarray_push_elem(PG_FUNCTION_ARGS)
 Datum
 intarray_push_array(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
-	ArrayType  *b = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(1)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P(1);
 	ArrayType  *result;
 
 	result = intarray_concat_arrays(a, b);
@@ -393,7 +374,7 @@ intarray_push_array(PG_FUNCTION_ARGS)
 Datum
 intarray_del_elem(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
 	int32		elem = PG_GETARG_INT32(1);
 	int32		c;
 	int32	   *aa;
@@ -401,7 +382,7 @@ intarray_del_elem(PG_FUNCTION_ARGS)
 				i;
 
 	CHECKARRVALID(a);
-	if (!ARRISVOID(a))
+	if (!ARRISEMPTY(a))
 	{
 		c = ARRNELEMS(a);
 		aa = ARRPTR(a);
@@ -423,7 +404,7 @@ intarray_del_elem(PG_FUNCTION_ARGS)
 Datum
 intset_union_elem(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM(PG_GETARG_DATUM(0)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
 	ArrayType  *result;
 
 	result = intarray_add_elem(a, PG_GETARG_INT32(1));
@@ -435,8 +416,8 @@ intset_union_elem(PG_FUNCTION_ARGS)
 Datum
 intset_subtract(PG_FUNCTION_ARGS)
 {
-	ArrayType  *a = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0)));
-	ArrayType  *b = (ArrayType *) DatumGetPointer(PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(1)));
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P_COPY(1);
 	ArrayType  *result;
 	int32		ca;
 	int32		cb;
diff --git a/contrib/intarray/_int_tool.c b/contrib/intarray/_int_tool.c
index 8093103ba4..ddf07f042b 100644
--- a/contrib/intarray/_int_tool.c
+++ b/contrib/intarray/_int_tool.c
@@ -8,6 +8,7 @@
 #include "_int.h"
 
 
+/* arguments are assumed sorted & unique-ified */
 bool
 inner_int_contains(ArrayType *a, ArrayType *b)
 {
@@ -19,12 +20,6 @@ inner_int_contains(ArrayType *a, ArrayType *b)
 	int		   *da,
 			   *db;
 
-	CHECKARRVALID(a);
-	CHECKARRVALID(b);
-
-	if (ARRISVOID(a) || ARRISVOID(b))
-		return FALSE;
-
 	na = ARRNELEMS(a);
 	nb = ARRNELEMS(b);
 	da = ARRPTR(a);
@@ -32,6 +27,7 @@ inner_int_contains(ArrayType *a, ArrayType *b)
 
 	i = j = n = 0;
 	while (i < na && j < nb)
+	{
 		if (da[i] < db[j])
 			i++;
 		else if (da[i] == db[j])
@@ -41,11 +37,13 @@ inner_int_contains(ArrayType *a, ArrayType *b)
 			j++;
 		}
 		else
-			break;
+			break;				/* db[j] is not in da */
+	}
 
 	return (n == nb) ? TRUE : FALSE;
 }
 
+/* arguments are assumed sorted */
 bool
 inner_int_overlap(ArrayType *a, ArrayType *b)
 {
@@ -56,12 +54,6 @@ inner_int_overlap(ArrayType *a, ArrayType *b)
 	int		   *da,
 			   *db;
 
-	CHECKARRVALID(a);
-	CHECKARRVALID(b);
-
-	if (ARRISVOID(a) || ARRISVOID(b))
-		return FALSE;
-
 	na = ARRNELEMS(a);
 	nb = ARRNELEMS(b);
 	da = ARRPTR(a);
@@ -69,12 +61,14 @@ inner_int_overlap(ArrayType *a, ArrayType *b)
 
 	i = j = 0;
 	while (i < na && j < nb)
+	{
 		if (da[i] < db[j])
 			i++;
 		else if (da[i] == db[j])
 			return TRUE;
 		else
 			j++;
+	}
 
 	return FALSE;
 }
@@ -87,11 +81,11 @@ inner_int_union(ArrayType *a, ArrayType *b)
 	CHECKARRVALID(a);
 	CHECKARRVALID(b);
 
-	if (ARRISVOID(a) && ARRISVOID(b))
+	if (ARRISEMPTY(a) && ARRISEMPTY(b))
 		return new_intArrayType(0);
-	if (ARRISVOID(a))
+	if (ARRISEMPTY(a))
 		r = copy_intArrayType(b);
-	if (ARRISVOID(b))
+	if (ARRISEMPTY(b))
 		r = copy_intArrayType(a);
 
 	if (!r)
@@ -148,10 +142,7 @@ inner_int_inter(ArrayType *a, ArrayType *b)
 	int			i,
 				j;
 
-	CHECKARRVALID(a);
-	CHECKARRVALID(b);
-
-	if (ARRISVOID(a) || ARRISVOID(b))
+	if (ARRISEMPTY(a) || ARRISEMPTY(b))
 		return new_intArrayType(0);
 
 	na = ARRNELEMS(a);
@@ -163,6 +154,7 @@ inner_int_inter(ArrayType *a, ArrayType *b)
 
 	i = j = 0;
 	while (i < na && j < nb)
+	{
 		if (da[i] < db[j])
 			i++;
 		else if (da[i] == db[j])
@@ -174,6 +166,7 @@ inner_int_inter(ArrayType *a, ArrayType *b)
 		}
 		else
 			j++;
+	}
 
 	if ((dr - ARRPTR(r)) == 0)
 	{
@@ -188,57 +181,60 @@ void
 rt__int_size(ArrayType *a, float *size)
 {
 	*size = (float) ARRNELEMS(a);
-
-	return;
 }
 
-
-/* len >= 2 */
+/* Sort the given data (len >= 2).  Return true if any duplicates found */
 bool
 isort(int4 *a, int len)
 {
-	int4		tmp,
-				index;
-	int4	   *cur,
+	int4		cur,
+				prev;
+	int4	   *pcur,
+			   *pprev,
 			   *end;
 	bool		r = FALSE;
 
+	/*
+	 * We use a simple insertion sort.  While this is O(N^2) in the worst
+	 * case, it's quite fast if the input is already sorted or nearly so.
+	 * Also, for not-too-large inputs it's faster than more complex methods
+	 * anyhow.
+	 */
 	end = a + len;
-	do
+	for (pcur = a + 1; pcur < end; pcur++)
 	{
-		index = 0;
-		cur = a + 1;
-		while (cur < end)
+		cur = *pcur;
+		for (pprev = pcur - 1; pprev >= a; pprev--)
 		{
-			if (*(cur - 1) > *cur)
+			prev = *pprev;
+			if (prev <= cur)
 			{
-				tmp = *(cur - 1);
-				*(cur - 1) = *cur;
-				*cur = tmp;
-				index = 1;
+				if (prev == cur)
+					r = TRUE;
+				break;
 			}
-			else if (!r && *(cur - 1) == *cur)
-				r = TRUE;
-			cur++;
+			pprev[1] = prev;
 		}
-	} while (index);
+		pprev[1] = cur;
+	}
 	return r;
 }
 
+/* Create a new int array with room for "num" elements */
 ArrayType *
 new_intArrayType(int num)
 {
 	ArrayType  *r;
-	int			nbytes = ARR_OVERHEAD_NONULLS(NDIM) + sizeof(int) * num;
+	int			nbytes = ARR_OVERHEAD_NONULLS(1) + sizeof(int) * num;
 
 	r = (ArrayType *) palloc0(nbytes);
 
 	SET_VARSIZE(r, nbytes);
-	ARR_NDIM(r) = NDIM;
+	ARR_NDIM(r) = 1;
 	r->dataoffset = 0;			/* marker for no null bitmap */
 	ARR_ELEMTYPE(r) = INT4OID;
-	*((int *) ARR_DIMS(r)) = num;
-	*((int *) ARR_LBOUND(r)) = 1;
+	ARR_DIMS(r)[0] = num;
+	ARR_LBOUND(r)[0] = 1;
 
 	return r;
 }
@@ -246,7 +242,8 @@ new_intArrayType(int num)
 ArrayType *
 resize_intArrayType(ArrayType *a, int num)
 {
-	int			nbytes = ARR_OVERHEAD_NONULLS(NDIM) + sizeof(int) * num;
+	int			nbytes = ARR_DATA_OFFSET(a) + sizeof(int) * num;
+	int			i;
 
 	if (num == ARRNELEMS(a))
 		return a;
@@ -254,7 +251,12 @@ resize_intArrayType(ArrayType *a, int num)
 	a = (ArrayType *) repalloc(a, nbytes);
 
 	SET_VARSIZE(a, nbytes);
-	*((int *) ARR_DIMS(a)) = num;
+	/* usually the array should be 1-D already, but just in case ... */
+	for (i = 0; i < ARR_NDIM(a); i++)
+	{
+		ARR_DIMS(a)[i] = num;
+		num = 1;
+	}
 	return a;
 }
 
@@ -262,9 +264,10 @@ ArrayType *
 copy_intArrayType(ArrayType *a)
 {
 	ArrayType  *r;
+	int			n = ARRNELEMS(a);
 
-	r = new_intArrayType(ARRNELEMS(a));
-	memmove(r, a, VARSIZE(r));
+	r = new_intArrayType(n);
+	memcpy(ARRPTR(r), ARRPTR(a), n * sizeof(int4));
 	return r;
 }
 
@@ -276,13 +279,15 @@ internal_size(int *a, int len)
 				size = 0;
 
 	for (i = 0; i < len; i += 2)
+	{
 		if (!i || a[i] != a[i - 1])		/* do not count repeated range */
 			size += a[i + 1] - a[i] + 1;
+	}
 
 	return size;
 }
 
-/* r is sorted and size of r > 1 */
+/* unique-ify elements of r in-place ... r must be sorted already */
 ArrayType *
 _int_unique(ArrayType *r)
 {
@@ -291,17 +296,17 @@ _int_unique(ArrayType *r)
 			   *data;
 	int			num = ARRNELEMS(r);
 
-	CHECKARRVALID(r);
-
 	if (num < 2)
 		return r;
 
 	data = tmp = dr = ARRPTR(r);
 	while (tmp - data < num)
+	{
 		if (*tmp != *dr)
 			*(++dr) = *tmp++;
 		else
 			tmp++;
+	}
 	return resize_intArrayType(r, dr + 1 - ARRPTR(r));
 }
 
@@ -326,8 +331,6 @@ intarray_match_first(ArrayType *a, int32 elem)
 				i;
 
 	CHECKARRVALID(a);
-	if (ARRISVOID(a))
-		return 0;
 	c = ARRNELEMS(a);
 	aa = ARRPTR(a);
 	for (i = 0; i < c; i++)
@@ -344,7 +347,7 @@ intarray_add_elem(ArrayType *a, int32 elem)
 	int32		c;
 
 	CHECKARRVALID(a);
-	c = (ARRISVOID(a)) ? 0 : ARRNELEMS(a);
+	c = ARRNELEMS(a);
 	result = new_intArrayType(c + 1);
 	r = ARRPTR(result);
 	if (c > 0)
@@ -357,8 +360,8 @@ ArrayType *
 intarray_concat_arrays(ArrayType *a, ArrayType *b)
 {
 	ArrayType  *result;
-	int32		ac = (ARRISVOID(a)) ? 0 : ARRNELEMS(a);
-	int32		bc = (ARRISVOID(b)) ? 0 : ARRNELEMS(b);
+	int32		ac = ARRNELEMS(a);
+	int32		bc = ARRNELEMS(b);
 
 	CHECKARRVALID(a);
 	CHECKARRVALID(b);
diff --git a/contrib/intarray/_intbig_gist.c b/contrib/intarray/_intbig_gist.c
index d9557a6b11..eb8f282634 100644
--- a/contrib/intarray/_intbig_gist.c
+++ b/contrib/intarray/_intbig_gist.c
@@ -153,13 +153,13 @@ g_intbig_compress(PG_FUNCTION_ARGS)
 	if (entry->leafkey)
 	{
 		GISTENTRY  *retval;
-		ArrayType  *in = (ArrayType *) PG_DETOAST_DATUM(entry->key);
+		ArrayType  *in = DatumGetArrayTypeP(entry->key);
 		int4	   *ptr;
 		int			num;
 		GISTTYPE   *res = (GISTTYPE *) palloc0(CALCGTSIZE(0));
 
 		CHECKARRVALID(in);
-		if (ARRISVOID(in))
+		if (ARRISEMPTY(in))
 		{
 			ptr = NULL;
 			num = 0;
@@ -182,7 +182,7 @@ g_intbig_compress(PG_FUNCTION_ARGS)
 					  entry->rel, entry->page,
 					  entry->offset, FALSE);
 
-		if (in != (ArrayType *) PG_DETOAST_DATUM(entry->key))
+		if (in != DatumGetArrayTypeP(entry->key))
 			pfree(in);
 
 		PG_RETURN_POINTER(retval);
@@ -504,7 +504,7 @@ Datum
 g_intbig_consistent(PG_FUNCTION_ARGS)
 {
 	GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
-	ArrayType  *query = (ArrayType *) PG_DETOAST_DATUM(PG_GETARG_POINTER(1));
+	ArrayType  *query = PG_GETARG_ARRAYTYPE_P(1);
 	StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
 
 	/* Oid		subtype = PG_GETARG_OID(3); */
@@ -527,11 +527,6 @@ g_intbig_consistent(PG_FUNCTION_ARGS)
 	}
 
 	CHECKARRVALID(query);
-	if (ARRISVOID(query))
-	{
-		PG_FREE_IF_COPY(query, 1);
-		PG_RETURN_BOOL(FALSE);
-	}
 
 	switch (strategy)
 	{
@@ -548,8 +543,6 @@ g_intbig_consistent(PG_FUNCTION_ARGS)
 				BITVECP		dq,
 							de;
 
-				CHECKARRVALID(query);
-
 				memset(qp, 0, sizeof(BITVEC));
 
 				while (num--)
@@ -589,8 +582,6 @@ g_intbig_consistent(PG_FUNCTION_ARGS)
 				BITVECP		dq,
 							de;
 
-				CHECKARRVALID(query);
-
 				memset(qp, 0, sizeof(BITVEC));
 
 				while (num--)
diff --git a/contrib/intarray/uninstall__int.sql b/contrib/intarray/uninstall__int.sql
index 5cda23fdad..345ad4464b 100644
--- a/contrib/intarray/uninstall__int.sql
+++ b/contrib/intarray/uninstall__int.sql
@@ -5,9 +5,9 @@ SET search_path = public;
 
 DROP OPERATOR CLASS gin__int_ops USING gin;
 
-DROP FUNCTION ginint4_queryextract(internal, internal, int2, internal, internal);
+DROP FUNCTION ginint4_queryextract(internal, internal, int2, internal, internal, internal, internal);
 
-DROP FUNCTION ginint4_consistent(internal, int2, internal, int4, internal, internal);
+DROP FUNCTION ginint4_consistent(internal, int2, internal, int4, internal, internal, internal, internal);
 
 DROP OPERATOR CLASS gist__intbig_ops USING gist;
 
diff --git a/doc/src/sgml/intarray.sgml b/doc/src/sgml/intarray.sgml
index 1cf72a1201..449878d671 100644
--- a/doc/src/sgml/intarray.sgml
+++ b/doc/src/sgml/intarray.sgml
@@ -9,10 +9,21 @@
 
  <para>
   The <filename>intarray</> module provides a number of useful functions
-  and operators for manipulating one-dimensional arrays of integers.
+  and operators for manipulating null-free arrays of integers.
   There is also support for indexed searches using some of the operators.
  </para>
 
+ <para>
+  All of these operations will throw an error if a supplied array contains any
+  NULL elements.
+ </para>
+
+ <para>
+  Many of these operations are only sensible for one-dimensional arrays.
+  Although they will accept input arrays of more dimensions, the data is
+  treated as though it were a linear array in storage order.
+ </para>
+
  <sect2>
   <title><filename>intarray</> Functions and Operators</title>
 
@@ -211,14 +222,12 @@
   </para>
 
   <para>
-   The containment operators <literal>@&gt;</> and <literal>&lt;@</> are
-   approximately equivalent to <productname>PostgreSQL</>'s built-in operators
-   of the same names, except that they work only on integer arrays while the
-   built-in operators work for any array type.  An important difference is
-   that <filename>intarray</>'s operators do not consider an empty array to be
-   contained in anything else.  This is consistent with the behavior of
-   GIN-indexed queries, but not with the usual mathematical definition of
-   containment.
+   The operators <literal>&amp;&amp;</>, <literal>@&gt;</> and
+   <literal>&lt;@</> are equivalent to <productname>PostgreSQL</>'s built-in
+   operators of the same names, except that they work only on integer arrays
+   that do not contain nulls, while the built-in operators work for any array
+   type.  This restriction makes them faster than the built-in operators
+   in many cases.
   </para>
 
   <para>