Selectivity estimation for intarray

diff --git a/contrib/intarray/Makefile b/contrib/intarray/Makefile
new file mode 100644
index 920c5b1..c37aeb9
*** a/contrib/intarray/Makefile
--- b/contrib/intarray/Makefile
***************
*** 2,8 ****
  
  MODULE_big = _int
  OBJS = _int_bool.o _int_gist.o _int_op.o _int_tool.o \
! 	_intbig_gist.o _int_gin.o $(WIN32RES)
  
  EXTENSION = intarray
  DATA = intarray--1.0.sql intarray--unpackaged--1.0.sql
--- 2,8 ----
  
  MODULE_big = _int
  OBJS = _int_bool.o _int_gist.o _int_op.o _int_tool.o \
! 	_intbig_gist.o _int_gin.o _int_selfuncs.o $(WIN32RES)
  
  EXTENSION = intarray
  DATA = intarray--1.0.sql intarray--unpackaged--1.0.sql
diff --git a/contrib/intarray/_int_selfuncs.c b/contrib/intarray/_int_selfuncs.c
new file mode 100644
index ...495aac8
*** a/contrib/intarray/_int_selfuncs.c
--- b/contrib/intarray/_int_selfuncs.c
***************
*** 0 ****
--- 1,83 ----
+ /*-------------------------------------------------------------------------
+  *
+  * _int_selfuncs.c
+  *	  Functions for selectivity estimation of intarray operators
+  *
+  * Portions Copyright (c) 1996-2014, PostgreSQL Global Development Group
+  * Portions Copyright (c) 1994, Regents of the University of California
+  *
+  *
+  * IDENTIFICATION
+  *	  contrib/intarray/_int_selfuncs.c
+  *
+  *-------------------------------------------------------------------------
+  */
+ #include "postgres.h"
+ 
+ #include "access/htup_details.h"
+ #include "catalog/pg_operator.h"
+ #include "utils/selfuncs.h"
+ #include "utils/syscache.h"
+ 
+ PG_FUNCTION_INFO_V1(_int_contsel);
+ PG_FUNCTION_INFO_V1(_int_contjoinsel);
+ 
+ Datum _int_contsel(PG_FUNCTION_ARGS);
+ Datum _int_contjoinsel(PG_FUNCTION_ARGS);
+ 
+ static Oid transformOperator(Oid oprOid);
+ 
+ static Oid
+ transformOperator(Oid oprOid)
+ {
+ 	HeapTuple			tup;
+ 	Form_pg_operator	op;
+ 	Oid					result = InvalidOid;
+ 
+ 	tup = SearchSysCache1(OPEROID, ObjectIdGetDatum(oprOid));
+ 	if (!HeapTupleIsValid(tup))
+ 		elog(ERROR, "Invalid operator: %u", oprOid);
+ 
+ 	op = (Form_pg_operator) GETSTRUCT(tup);
+ 
+ 	if (!strcmp(op->oprname.data, "&&"))
+ 		result = OID_ARRAY_OVERLAP_OP;
+ 	else if (!strcmp(op->oprname.data, "@>"))
+ 		result = OID_ARRAY_CONTAINS_OP;
+ 	else if (!strcmp(op->oprname.data, "<@"))
+ 		result = OID_ARRAY_CONTAINED_OP;
+ 
+ 	ReleaseSysCache(tup);
+ 
+ 	if (!OidIsValid(result))
+ 		elog(ERROR, "Invalid operator: %u", oprOid);
+ 
+ 	return result;
+ }
+ 
+ /*
+  * _int_contsel -- restriction selectivity for array @>, &&, <@ operators
+  */
+ Datum
+ _int_contsel(PG_FUNCTION_ARGS)
+ {
+ 	PG_RETURN_DATUM(DirectFunctionCall4(arraycontsel,
+ 			PG_GETARG_DATUM(0),
+ 			ObjectIdGetDatum(transformOperator(PG_GETARG_OID(1))),
+ 			PG_GETARG_DATUM(2),
+ 			PG_GETARG_DATUM(3)));
+ }
+ 
+ /*
+  * _int_contjoinsel -- join selectivity for array @>, &&, <@ operators
+  */
+ Datum
+ _int_contjoinsel(PG_FUNCTION_ARGS)
+ {
+ 	PG_RETURN_DATUM(DirectFunctionCall5(arraycontjoinsel,
+ 			PG_GETARG_DATUM(0),
+ 			ObjectIdGetDatum(transformOperator(PG_GETARG_OID(1))),
+ 			PG_GETARG_DATUM(2),
+ 			PG_GETARG_DATUM(3),
+ 			PG_GETARG_DATUM(4)));
+ }
diff --git a/contrib/intarray/intarray--1.0.sql b/contrib/intarray/intarray--1.0.sql
new file mode 100644
index 0b89e0f..72fb4c2
*** a/contrib/intarray/intarray--1.0.sql
--- b/contrib/intarray/intarray--1.0.sql
*************** RETURNS _int4
*** 117,122 ****
--- 117,132 ----
  AS 'MODULE_PATHNAME'
  LANGUAGE C STRICT IMMUTABLE;
  
+ CREATE FUNCTION _int_contsel(internal, oid, internal, integer)
+ RETURNS float8
+ AS 'MODULE_PATHNAME'
+ LANGUAGE C STRICT STABLE;
+ 
+ CREATE FUNCTION _int_contjoinsel(internal, oid, internal, smallint, internal)
+ RETURNS float8
+ AS 'MODULE_PATHNAME'
+ LANGUAGE C STRICT STABLE;
+ 
  --
  -- OPERATORS
  --
*************** CREATE OPERATOR && (
*** 126,133 ****
  	RIGHTARG = _int4,
  	PROCEDURE = _int_overlap,
  	COMMUTATOR = '&&',
! 	RESTRICT = contsel,
! 	JOIN = contjoinsel
  );
  
  --CREATE OPERATOR = (
--- 136,143 ----
  	RIGHTARG = _int4,
  	PROCEDURE = _int_overlap,
  	COMMUTATOR = '&&',
! 	RESTRICT = _int_contsel,
! 	JOIN = _int_contjoinsel
  );
  
  --CREATE OPERATOR = (
*************** CREATE OPERATOR @> (
*** 157,164 ****
  	RIGHTARG = _int4,
  	PROCEDURE = _int_contains,
  	COMMUTATOR = '<@',
! 	RESTRICT = contsel,
! 	JOIN = contjoinsel
  );
  
  CREATE OPERATOR <@ (
--- 167,174 ----
  	RIGHTARG = _int4,
  	PROCEDURE = _int_contains,
  	COMMUTATOR = '<@',
! 	RESTRICT = _int_contsel,
! 	JOIN = _int_contjoinsel
  );
  
  CREATE OPERATOR <@ (
*************** CREATE OPERATOR <@ (
*** 166,173 ****
  	RIGHTARG = _int4,
  	PROCEDURE = _int_contained,
  	COMMUTATOR = '@>',
! 	RESTRICT = contsel,
! 	JOIN = contjoinsel
  );
  
  -- obsolete:
--- 176,183 ----
  	RIGHTARG = _int4,
  	PROCEDURE = _int_contained,
  	COMMUTATOR = '@>',
! 	RESTRICT = _int_contsel,
! 	JOIN = _int_contjoinsel
  );
  
  -- obsolete: