bms_fixes.patch

diff --git a/src/backend/nodes/bitmapset.c b/src/backend/nodes/bitmapset.c
index ac3e763de43..46b4ca4b0f1 100644
--- a/src/backend/nodes/bitmapset.c
+++ b/src/backend/nodes/bitmapset.c
@@ -1444,6 +1444,7 @@ bms_join(Bitmapset *a, Bitmapset *b)
 int
 bms_next_member(const Bitmapset *a, int prevbit)
 {
+	int64		currbit;
 	int			nwords;
 	bitmapword	mask;
 
@@ -1452,13 +1453,13 @@ bms_next_member(const Bitmapset *a, int prevbit)
 	if (a == NULL)
 		return -2;
 	nwords = a->nwords;
-	prevbit++;
-	mask = (~(bitmapword) 0) << BITNUM(prevbit);
-	for (int wordnum = WORDNUM(prevbit); wordnum < nwords; wordnum++)
+	currbit = (int64) prevbit + 1;
+	mask = (~(bitmapword) 0) << BITNUM(currbit);
+	for (int wordnum = WORDNUM(currbit); wordnum < nwords; wordnum++)
 	{
 		bitmapword	w = a->words[wordnum];
 
-		/* ignore bits before prevbit */
+		/* ignore bits before currbit */
 		w &= mask;
 
 		if (w != 0)
@@ -1505,6 +1506,7 @@ int
 bms_prev_member(const Bitmapset *a, int prevbit)
 {
 	int			ushiftbits;
+	uint32		currbit;
 	bitmapword	mask;
 
 	Assert(bms_is_valid_set(a));
@@ -1517,18 +1519,18 @@ bms_prev_member(const Bitmapset *a, int prevbit)
 		return -2;
 
 	/* Validate callers didn't give us something out of range */
-	Assert(prevbit <= a->nwords * BITS_PER_BITMAPWORD);
+	Assert(prevbit <= (int64) a->nwords * BITS_PER_BITMAPWORD);
 	Assert(prevbit >= -1);
 
 	/* transform -1 to the highest possible bit we could have set */
 	if (prevbit == -1)
-		prevbit = a->nwords * BITS_PER_BITMAPWORD - 1;
+		currbit = (uint32) a->nwords * BITS_PER_BITMAPWORD - 1;
 	else
-		prevbit--;
+		currbit = prevbit - 1;
 
-	ushiftbits = BITS_PER_BITMAPWORD - (BITNUM(prevbit) + 1);
+	ushiftbits = BITS_PER_BITMAPWORD - (BITNUM(currbit) + 1);
 	mask = (~(bitmapword) 0) >> ushiftbits;
-	for (int wordnum = WORDNUM(prevbit); wordnum >= 0; wordnum--)
+	for (int wordnum = WORDNUM(currbit); wordnum >= 0; wordnum--)
 	{
 		bitmapword	w = a->words[wordnum];
 
diff --git a/src/test/modules/test_bitmapset/test_bitmapset--1.0.sql b/src/test/modules/test_bitmapset/test_bitmapset--1.0.sql
index 6668bcef9a9..d6c0f739e13 100644
--- a/src/test/modules/test_bitmapset/test_bitmapset--1.0.sql
+++ b/src/test/modules/test_bitmapset/test_bitmapset--1.0.sql
@@ -3,6 +3,15 @@
 -- complain if script is sourced in psql, rather than via CREATE EXTENSION
 \echo Use "CREATE EXTENSION test_bitmapset" to load this file. \quit
 
+-- Benchmark functions
+CREATE FUNCTION bench_bms_next_member(text, integer)
+RETURNS bigint
+AS 'MODULE_PATHNAME' LANGUAGE C;
+
+CREATE FUNCTION bench_bms_prev_member(text, integer)
+RETURNS bigint
+AS 'MODULE_PATHNAME' LANGUAGE C;
+
 -- Bitmapset API functions
 CREATE FUNCTION test_bms_make_singleton(integer)
 RETURNS text STRICT
diff --git a/src/test/modules/test_bitmapset/test_bitmapset.c b/src/test/modules/test_bitmapset/test_bitmapset.c
index 4fe22ee64d2..990347a0f22 100644
--- a/src/test/modules/test_bitmapset/test_bitmapset.c
+++ b/src/test/modules/test_bitmapset/test_bitmapset.c
@@ -17,6 +17,7 @@
 #include "postgres.h"
 
 #include <stddef.h>
+#include <time.h>
 #include "catalog/pg_type.h"
 #include "common/pg_prng.h"
 #include "utils/array.h"
@@ -27,8 +28,13 @@
 #include "utils/builtins.h"
 #include "utils/timestamp.h"
 
+
 PG_MODULE_MAGIC;
 
+/* Benchmark functions */
+PG_FUNCTION_INFO_V1(bench_bms_next_member);
+PG_FUNCTION_INFO_V1(bench_bms_prev_member);
+
 /* Bitmapset API functions in order of appearance in bitmapset.c */
 PG_FUNCTION_INFO_V1(test_bms_make_singleton);
 PG_FUNCTION_INFO_V1(test_bms_add_member);
@@ -105,6 +111,73 @@ PG_FUNCTION_INFO_V1(test_random_shift_operations);
 #define PG_RETURN_BITMAPSET_AS_TEXT(bms) \
 	PG_RETURN_TEXT_P(BITMAPSET_TO_TEXT(bms))
 
+#define NANOSEC_PER_SEC 1000000000
+
+int64 get_clock_diff(struct timespec* t1, struct timespec* t2);
+
+int64
+get_clock_diff(struct timespec* t1, struct timespec* t2)
+{
+	int64_t nanosec = (t1->tv_sec - t2->tv_sec) * NANOSEC_PER_SEC;
+	nanosec += (t1->tv_nsec - t2->tv_nsec);
+
+	return nanosec;
+}
+
+Datum
+bench_bms_next_member(PG_FUNCTION_ARGS)
+{
+	Bitmapset* bms = PG_ARG_GETBITMAPSET(0);
+	int32	loops = PG_GETARG_INT32(1);
+
+	struct timespec start, end;
+	int64 nanoseconds;
+	int64 counter = 0;
+
+	clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &start);
+
+	for (int i = 0; i < loops; i++)
+	{
+		int m = -1;
+		while ((m = bms_next_member(bms, m)) >= 0)
+		{
+			counter++;
+		}
+	}
+
+	clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &end);
+	nanoseconds = get_clock_diff(&end, &start);
+
+	PG_RETURN_INT64(nanoseconds);
+}
+
+Datum
+bench_bms_prev_member(PG_FUNCTION_ARGS)
+{
+	Bitmapset* bms = PG_ARG_GETBITMAPSET(0);
+	int32	loops = PG_GETARG_INT32(1);
+
+	struct timespec start, end;
+	int64 nanoseconds;
+	int64 counter = 0;
+
+	clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &start);
+
+	for (int i = 0; i < loops; i++)
+	{
+		int m = -1;
+		while ((m = bms_prev_member(bms, m)) >= 0)
+		{
+			counter++;
+		}
+	}
+
+	clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &end);
+	nanoseconds = get_clock_diff(&end, &start);
+
+	PG_RETURN_INT64(nanoseconds);
+}
+
 /*
  * Individual test functions for each bitmapset API function
  *