Adding upstream version 14.5.upstream/14.5upstream

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

1 files changed, 1566 insertions, 0 deletions

diff --git a/src/backend/utils/adt/int8.c b/src/backend/utils/adt/int8.c
new file mode 100644
index 0000000..2168080
--- /dev/null
+++ b/src/backend/utils/adt/int8.c
@@ -0,0 +1,1566 @@
+/*-------------------------------------------------------------------------
+ *
+ * int8.c
+ *	  Internal 64-bit integer operations
+ *
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ *	  src/backend/utils/adt/int8.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include <ctype.h>
+#include <limits.h>
+#include <math.h>
+
+#include "common/int.h"
+#include "funcapi.h"
+#include "libpq/pqformat.h"
+#include "nodes/nodeFuncs.h"
+#include "nodes/supportnodes.h"
+#include "optimizer/optimizer.h"
+#include "utils/builtins.h"
+#include "utils/int8.h"
+
+
+typedef struct
+{
+	int64		current;
+	int64		finish;
+	int64		step;
+} generate_series_fctx;
+
+
+/***********************************************************************
+ **
+ **		Routines for 64-bit integers.
+ **
+ ***********************************************************************/
+
+/*----------------------------------------------------------
+ * Formatting and conversion routines.
+ *---------------------------------------------------------*/
+
+/*
+ * scanint8 --- try to parse a string into an int8.
+ *
+ * If errorOK is false, ereport a useful error message if the string is bad.
+ * If errorOK is true, just return "false" for bad input.
+ */
+bool
+scanint8(const char *str, bool errorOK, int64 *result)
+{
+	const char *ptr = str;
+	int64		tmp = 0;
+	bool		neg = false;
+
+	/*
+	 * Do our own scan, rather than relying on sscanf which might be broken
+	 * for long long.
+	 *
+	 * As INT64_MIN can't be stored as a positive 64 bit integer, accumulate
+	 * value as a negative number.
+	 */
+
+	/* skip leading spaces */
+	while (*ptr && isspace((unsigned char) *ptr))
+		ptr++;
+
+	/* handle sign */
+	if (*ptr == '-')
+	{
+		ptr++;
+		neg = true;
+	}
+	else if (*ptr == '+')
+		ptr++;
+
+	/* require at least one digit */
+	if (unlikely(!isdigit((unsigned char) *ptr)))
+		goto invalid_syntax;
+
+	/* process digits */
+	while (*ptr && isdigit((unsigned char) *ptr))
+	{
+		int8		digit = (*ptr++ - '0');
+
+		if (unlikely(pg_mul_s64_overflow(tmp, 10, &tmp)) ||
+			unlikely(pg_sub_s64_overflow(tmp, digit, &tmp)))
+			goto out_of_range;
+	}
+
+	/* allow trailing whitespace, but not other trailing chars */
+	while (*ptr != '\0' && isspace((unsigned char) *ptr))
+		ptr++;
+
+	if (unlikely(*ptr != '\0'))
+		goto invalid_syntax;
+
+	if (!neg)
+	{
+		/* could fail if input is most negative number */
+		if (unlikely(tmp == PG_INT64_MIN))
+			goto out_of_range;
+		tmp = -tmp;
+	}
+
+	*result = tmp;
+	return true;
+
+out_of_range:
+	if (!errorOK)
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("value \"%s\" is out of range for type %s",
+						str, "bigint")));
+	return false;
+
+invalid_syntax:
+	if (!errorOK)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+				 errmsg("invalid input syntax for type %s: \"%s\"",
+						"bigint", str)));
+	return false;
+}
+
+/* int8in()
+ */
+Datum
+int8in(PG_FUNCTION_ARGS)
+{
+	char	   *str = PG_GETARG_CSTRING(0);
+	int64		result;
+
+	(void) scanint8(str, false, &result);
+	PG_RETURN_INT64(result);
+}
+
+
+/* int8out()
+ */
+Datum
+int8out(PG_FUNCTION_ARGS)
+{
+	int64		val = PG_GETARG_INT64(0);
+	char		buf[MAXINT8LEN + 1];
+	char	   *result;
+	int			len;
+
+	len = pg_lltoa(val, buf) + 1;
+
+	/*
+	 * Since the length is already known, we do a manual palloc() and memcpy()
+	 * to avoid the strlen() call that would otherwise be done in pstrdup().
+	 */
+	result = palloc(len);
+	memcpy(result, buf, len);
+	PG_RETURN_CSTRING(result);
+}
+
+/*
+ *		int8recv			- converts external binary format to int8
+ */
+Datum
+int8recv(PG_FUNCTION_ARGS)
+{
+	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);
+
+	PG_RETURN_INT64(pq_getmsgint64(buf));
+}
+
+/*
+ *		int8send			- converts int8 to binary format
+ */
+Datum
+int8send(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	StringInfoData buf;
+
+	pq_begintypsend(&buf);
+	pq_sendint64(&buf, arg1);
+	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
+}
+
+
+/*----------------------------------------------------------
+ *	Relational operators for int8s, including cross-data-type comparisons.
+ *---------------------------------------------------------*/
+
+/* int8relop()
+ * Is val1 relop val2?
+ */
+Datum
+int8eq(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 == val2);
+}
+
+Datum
+int8ne(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 != val2);
+}
+
+Datum
+int8lt(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 < val2);
+}
+
+Datum
+int8gt(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 > val2);
+}
+
+Datum
+int8le(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 <= val2);
+}
+
+Datum
+int8ge(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 >= val2);
+}
+
+/* int84relop()
+ * Is 64-bit val1 relop 32-bit val2?
+ */
+Datum
+int84eq(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int32		val2 = PG_GETARG_INT32(1);
+
+	PG_RETURN_BOOL(val1 == val2);
+}
+
+Datum
+int84ne(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int32		val2 = PG_GETARG_INT32(1);
+
+	PG_RETURN_BOOL(val1 != val2);
+}
+
+Datum
+int84lt(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int32		val2 = PG_GETARG_INT32(1);
+
+	PG_RETURN_BOOL(val1 < val2);
+}
+
+Datum
+int84gt(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int32		val2 = PG_GETARG_INT32(1);
+
+	PG_RETURN_BOOL(val1 > val2);
+}
+
+Datum
+int84le(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int32		val2 = PG_GETARG_INT32(1);
+
+	PG_RETURN_BOOL(val1 <= val2);
+}
+
+Datum
+int84ge(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int32		val2 = PG_GETARG_INT32(1);
+
+	PG_RETURN_BOOL(val1 >= val2);
+}
+
+/* int48relop()
+ * Is 32-bit val1 relop 64-bit val2?
+ */
+Datum
+int48eq(PG_FUNCTION_ARGS)
+{
+	int32		val1 = PG_GETARG_INT32(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 == val2);
+}
+
+Datum
+int48ne(PG_FUNCTION_ARGS)
+{
+	int32		val1 = PG_GETARG_INT32(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 != val2);
+}
+
+Datum
+int48lt(PG_FUNCTION_ARGS)
+{
+	int32		val1 = PG_GETARG_INT32(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 < val2);
+}
+
+Datum
+int48gt(PG_FUNCTION_ARGS)
+{
+	int32		val1 = PG_GETARG_INT32(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 > val2);
+}
+
+Datum
+int48le(PG_FUNCTION_ARGS)
+{
+	int32		val1 = PG_GETARG_INT32(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 <= val2);
+}
+
+Datum
+int48ge(PG_FUNCTION_ARGS)
+{
+	int32		val1 = PG_GETARG_INT32(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 >= val2);
+}
+
+/* int82relop()
+ * Is 64-bit val1 relop 16-bit val2?
+ */
+Datum
+int82eq(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int16		val2 = PG_GETARG_INT16(1);
+
+	PG_RETURN_BOOL(val1 == val2);
+}
+
+Datum
+int82ne(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int16		val2 = PG_GETARG_INT16(1);
+
+	PG_RETURN_BOOL(val1 != val2);
+}
+
+Datum
+int82lt(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int16		val2 = PG_GETARG_INT16(1);
+
+	PG_RETURN_BOOL(val1 < val2);
+}
+
+Datum
+int82gt(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int16		val2 = PG_GETARG_INT16(1);
+
+	PG_RETURN_BOOL(val1 > val2);
+}
+
+Datum
+int82le(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int16		val2 = PG_GETARG_INT16(1);
+
+	PG_RETURN_BOOL(val1 <= val2);
+}
+
+Datum
+int82ge(PG_FUNCTION_ARGS)
+{
+	int64		val1 = PG_GETARG_INT64(0);
+	int16		val2 = PG_GETARG_INT16(1);
+
+	PG_RETURN_BOOL(val1 >= val2);
+}
+
+/* int28relop()
+ * Is 16-bit val1 relop 64-bit val2?
+ */
+Datum
+int28eq(PG_FUNCTION_ARGS)
+{
+	int16		val1 = PG_GETARG_INT16(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 == val2);
+}
+
+Datum
+int28ne(PG_FUNCTION_ARGS)
+{
+	int16		val1 = PG_GETARG_INT16(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 != val2);
+}
+
+Datum
+int28lt(PG_FUNCTION_ARGS)
+{
+	int16		val1 = PG_GETARG_INT16(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 < val2);
+}
+
+Datum
+int28gt(PG_FUNCTION_ARGS)
+{
+	int16		val1 = PG_GETARG_INT16(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 > val2);
+}
+
+Datum
+int28le(PG_FUNCTION_ARGS)
+{
+	int16		val1 = PG_GETARG_INT16(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 <= val2);
+}
+
+Datum
+int28ge(PG_FUNCTION_ARGS)
+{
+	int16		val1 = PG_GETARG_INT16(0);
+	int64		val2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_BOOL(val1 >= val2);
+}
+
+/*
+ * in_range support function for int8.
+ *
+ * Note: we needn't supply int8_int4 or int8_int2 variants, as implicit
+ * coercion of the offset value takes care of those scenarios just as well.
+ */
+Datum
+in_range_int8_int8(PG_FUNCTION_ARGS)
+{
+	int64		val = PG_GETARG_INT64(0);
+	int64		base = PG_GETARG_INT64(1);
+	int64		offset = PG_GETARG_INT64(2);
+	bool		sub = PG_GETARG_BOOL(3);
+	bool		less = PG_GETARG_BOOL(4);
+	int64		sum;
+
+	if (offset < 0)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PRECEDING_OR_FOLLOWING_SIZE),
+				 errmsg("invalid preceding or following size in window function")));
+
+	if (sub)
+		offset = -offset;		/* cannot overflow */
+
+	if (unlikely(pg_add_s64_overflow(base, offset, &sum)))
+	{
+		/*
+		 * If sub is false, the true sum is surely more than val, so correct
+		 * answer is the same as "less".  If sub is true, the true sum is
+		 * surely less than val, so the answer is "!less".
+		 */
+		PG_RETURN_BOOL(sub ? !less : less);
+	}
+
+	if (less)
+		PG_RETURN_BOOL(val <= sum);
+	else
+		PG_RETURN_BOOL(val >= sum);
+}
+
+
+/*----------------------------------------------------------
+ *	Arithmetic operators on 64-bit integers.
+ *---------------------------------------------------------*/
+
+Datum
+int8um(PG_FUNCTION_ARGS)
+{
+	int64		arg = PG_GETARG_INT64(0);
+	int64		result;
+
+	if (unlikely(arg == PG_INT64_MIN))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	result = -arg;
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int8up(PG_FUNCTION_ARGS)
+{
+	int64		arg = PG_GETARG_INT64(0);
+
+	PG_RETURN_INT64(arg);
+}
+
+Datum
+int8pl(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_add_s64_overflow(arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int8mi(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_sub_s64_overflow(arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int8mul(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_mul_s64_overflow(arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int8div(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (arg2 == 0)
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_DIVISION_BY_ZERO),
+				 errmsg("division by zero")));
+		/* ensure compiler realizes we mustn't reach the division (gcc bug) */
+		PG_RETURN_NULL();
+	}
+
+	/*
+	 * INT64_MIN / -1 is problematic, since the result can't be represented on
+	 * a two's-complement machine.  Some machines produce INT64_MIN, some
+	 * produce zero, some throw an exception.  We can dodge the problem by
+	 * recognizing that division by -1 is the same as negation.
+	 */
+	if (arg2 == -1)
+	{
+		if (unlikely(arg1 == PG_INT64_MIN))
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("bigint out of range")));
+		result = -arg1;
+		PG_RETURN_INT64(result);
+	}
+
+	/* No overflow is possible */
+
+	result = arg1 / arg2;
+
+	PG_RETURN_INT64(result);
+}
+
+/* int8abs()
+ * Absolute value
+ */
+Datum
+int8abs(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		result;
+
+	if (unlikely(arg1 == PG_INT64_MIN))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	result = (arg1 < 0) ? -arg1 : arg1;
+	PG_RETURN_INT64(result);
+}
+
+/* int8mod()
+ * Modulo operation.
+ */
+Datum
+int8mod(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+
+	if (unlikely(arg2 == 0))
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_DIVISION_BY_ZERO),
+				 errmsg("division by zero")));
+		/* ensure compiler realizes we mustn't reach the division (gcc bug) */
+		PG_RETURN_NULL();
+	}
+
+	/*
+	 * Some machines throw a floating-point exception for INT64_MIN % -1,
+	 * which is a bit silly since the correct answer is perfectly
+	 * well-defined, namely zero.
+	 */
+	if (arg2 == -1)
+		PG_RETURN_INT64(0);
+
+	/* No overflow is possible */
+
+	PG_RETURN_INT64(arg1 % arg2);
+}
+
+/*
+ * Greatest Common Divisor
+ *
+ * Returns the largest positive integer that exactly divides both inputs.
+ * Special cases:
+ *   - gcd(x, 0) = gcd(0, x) = abs(x)
+ *   		because 0 is divisible by anything
+ *   - gcd(0, 0) = 0
+ *   		complies with the previous definition and is a common convention
+ *
+ * Special care must be taken if either input is INT64_MIN ---
+ * gcd(0, INT64_MIN), gcd(INT64_MIN, 0) and gcd(INT64_MIN, INT64_MIN) are
+ * all equal to abs(INT64_MIN), which cannot be represented as a 64-bit signed
+ * integer.
+ */
+static int64
+int8gcd_internal(int64 arg1, int64 arg2)
+{
+	int64		swap;
+	int64		a1,
+				a2;
+
+	/*
+	 * Put the greater absolute value in arg1.
+	 *
+	 * This would happen automatically in the loop below, but avoids an
+	 * expensive modulo operation, and simplifies the special-case handling
+	 * for INT64_MIN below.
+	 *
+	 * We do this in negative space in order to handle INT64_MIN.
+	 */
+	a1 = (arg1 < 0) ? arg1 : -arg1;
+	a2 = (arg2 < 0) ? arg2 : -arg2;
+	if (a1 > a2)
+	{
+		swap = arg1;
+		arg1 = arg2;
+		arg2 = swap;
+	}
+
+	/* Special care needs to be taken with INT64_MIN.  See comments above. */
+	if (arg1 == PG_INT64_MIN)
+	{
+		if (arg2 == 0 || arg2 == PG_INT64_MIN)
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("bigint out of range")));
+
+		/*
+		 * Some machines throw a floating-point exception for INT64_MIN % -1,
+		 * which is a bit silly since the correct answer is perfectly
+		 * well-defined, namely zero.  Guard against this and just return the
+		 * result, gcd(INT64_MIN, -1) = 1.
+		 */
+		if (arg2 == -1)
+			return 1;
+	}
+
+	/* Use the Euclidean algorithm to find the GCD */
+	while (arg2 != 0)
+	{
+		swap = arg2;
+		arg2 = arg1 % arg2;
+		arg1 = swap;
+	}
+
+	/*
+	 * Make sure the result is positive. (We know we don't have INT64_MIN
+	 * anymore).
+	 */
+	if (arg1 < 0)
+		arg1 = -arg1;
+
+	return arg1;
+}
+
+Datum
+int8gcd(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	result = int8gcd_internal(arg1, arg2);
+
+	PG_RETURN_INT64(result);
+}
+
+/*
+ * Least Common Multiple
+ */
+Datum
+int8lcm(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		gcd;
+	int64		result;
+
+	/*
+	 * Handle lcm(x, 0) = lcm(0, x) = 0 as a special case.  This prevents a
+	 * division-by-zero error below when x is zero, and an overflow error from
+	 * the GCD computation when x = INT64_MIN.
+	 */
+	if (arg1 == 0 || arg2 == 0)
+		PG_RETURN_INT64(0);
+
+	/* lcm(x, y) = abs(x / gcd(x, y) * y) */
+	gcd = int8gcd_internal(arg1, arg2);
+	arg1 = arg1 / gcd;
+
+	if (unlikely(pg_mul_s64_overflow(arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+
+	/* If the result is INT64_MIN, it cannot be represented. */
+	if (unlikely(result == PG_INT64_MIN))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+
+	if (result < 0)
+		result = -result;
+
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int8inc(PG_FUNCTION_ARGS)
+{
+	/*
+	 * When int8 is pass-by-reference, we provide this special case to avoid
+	 * palloc overhead for COUNT(): when called as an aggregate, we know that
+	 * the argument is modifiable local storage, so just update it in-place.
+	 * (If int8 is pass-by-value, then of course this is useless as well as
+	 * incorrect, so just ifdef it out.)
+	 */
+#ifndef USE_FLOAT8_BYVAL		/* controls int8 too */
+	if (AggCheckCallContext(fcinfo, NULL))
+	{
+		int64	   *arg = (int64 *) PG_GETARG_POINTER(0);
+
+		if (unlikely(pg_add_s64_overflow(*arg, 1, arg)))
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("bigint out of range")));
+
+		PG_RETURN_POINTER(arg);
+	}
+	else
+#endif
+	{
+		/* Not called as an aggregate, so just do it the dumb way */
+		int64		arg = PG_GETARG_INT64(0);
+		int64		result;
+
+		if (unlikely(pg_add_s64_overflow(arg, 1, &result)))
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("bigint out of range")));
+
+		PG_RETURN_INT64(result);
+	}
+}
+
+Datum
+int8dec(PG_FUNCTION_ARGS)
+{
+	/*
+	 * When int8 is pass-by-reference, we provide this special case to avoid
+	 * palloc overhead for COUNT(): when called as an aggregate, we know that
+	 * the argument is modifiable local storage, so just update it in-place.
+	 * (If int8 is pass-by-value, then of course this is useless as well as
+	 * incorrect, so just ifdef it out.)
+	 */
+#ifndef USE_FLOAT8_BYVAL		/* controls int8 too */
+	if (AggCheckCallContext(fcinfo, NULL))
+	{
+		int64	   *arg = (int64 *) PG_GETARG_POINTER(0);
+
+		if (unlikely(pg_sub_s64_overflow(*arg, 1, arg)))
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("bigint out of range")));
+		PG_RETURN_POINTER(arg);
+	}
+	else
+#endif
+	{
+		/* Not called as an aggregate, so just do it the dumb way */
+		int64		arg = PG_GETARG_INT64(0);
+		int64		result;
+
+		if (unlikely(pg_sub_s64_overflow(arg, 1, &result)))
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("bigint out of range")));
+
+		PG_RETURN_INT64(result);
+	}
+}
+
+
+/*
+ * These functions are exactly like int8inc/int8dec but are used for
+ * aggregates that count only non-null values.  Since the functions are
+ * declared strict, the null checks happen before we ever get here, and all we
+ * need do is increment the state value.  We could actually make these pg_proc
+ * entries point right at int8inc/int8dec, but then the opr_sanity regression
+ * test would complain about mismatched entries for a built-in function.
+ */
+
+Datum
+int8inc_any(PG_FUNCTION_ARGS)
+{
+	return int8inc(fcinfo);
+}
+
+Datum
+int8inc_float8_float8(PG_FUNCTION_ARGS)
+{
+	return int8inc(fcinfo);
+}
+
+Datum
+int8dec_any(PG_FUNCTION_ARGS)
+{
+	return int8dec(fcinfo);
+}
+
+
+Datum
+int8larger(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	result = ((arg1 > arg2) ? arg1 : arg2);
+
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int8smaller(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	result = ((arg1 < arg2) ? arg1 : arg2);
+
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int84pl(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int32		arg2 = PG_GETARG_INT32(1);
+	int64		result;
+
+	if (unlikely(pg_add_s64_overflow(arg1, (int64) arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int84mi(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int32		arg2 = PG_GETARG_INT32(1);
+	int64		result;
+
+	if (unlikely(pg_sub_s64_overflow(arg1, (int64) arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int84mul(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int32		arg2 = PG_GETARG_INT32(1);
+	int64		result;
+
+	if (unlikely(pg_mul_s64_overflow(arg1, (int64) arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int84div(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int32		arg2 = PG_GETARG_INT32(1);
+	int64		result;
+
+	if (arg2 == 0)
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_DIVISION_BY_ZERO),
+				 errmsg("division by zero")));
+		/* ensure compiler realizes we mustn't reach the division (gcc bug) */
+		PG_RETURN_NULL();
+	}
+
+	/*
+	 * INT64_MIN / -1 is problematic, since the result can't be represented on
+	 * a two's-complement machine.  Some machines produce INT64_MIN, some
+	 * produce zero, some throw an exception.  We can dodge the problem by
+	 * recognizing that division by -1 is the same as negation.
+	 */
+	if (arg2 == -1)
+	{
+		if (unlikely(arg1 == PG_INT64_MIN))
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("bigint out of range")));
+		result = -arg1;
+		PG_RETURN_INT64(result);
+	}
+
+	/* No overflow is possible */
+
+	result = arg1 / arg2;
+
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int48pl(PG_FUNCTION_ARGS)
+{
+	int32		arg1 = PG_GETARG_INT32(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_add_s64_overflow((int64) arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int48mi(PG_FUNCTION_ARGS)
+{
+	int32		arg1 = PG_GETARG_INT32(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_sub_s64_overflow((int64) arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int48mul(PG_FUNCTION_ARGS)
+{
+	int32		arg1 = PG_GETARG_INT32(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_mul_s64_overflow((int64) arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int48div(PG_FUNCTION_ARGS)
+{
+	int32		arg1 = PG_GETARG_INT32(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+
+	if (unlikely(arg2 == 0))
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_DIVISION_BY_ZERO),
+				 errmsg("division by zero")));
+		/* ensure compiler realizes we mustn't reach the division (gcc bug) */
+		PG_RETURN_NULL();
+	}
+
+	/* No overflow is possible */
+	PG_RETURN_INT64((int64) arg1 / arg2);
+}
+
+Datum
+int82pl(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int16		arg2 = PG_GETARG_INT16(1);
+	int64		result;
+
+	if (unlikely(pg_add_s64_overflow(arg1, (int64) arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int82mi(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int16		arg2 = PG_GETARG_INT16(1);
+	int64		result;
+
+	if (unlikely(pg_sub_s64_overflow(arg1, (int64) arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int82mul(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int16		arg2 = PG_GETARG_INT16(1);
+	int64		result;
+
+	if (unlikely(pg_mul_s64_overflow(arg1, (int64) arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int82div(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int16		arg2 = PG_GETARG_INT16(1);
+	int64		result;
+
+	if (unlikely(arg2 == 0))
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_DIVISION_BY_ZERO),
+				 errmsg("division by zero")));
+		/* ensure compiler realizes we mustn't reach the division (gcc bug) */
+		PG_RETURN_NULL();
+	}
+
+	/*
+	 * INT64_MIN / -1 is problematic, since the result can't be represented on
+	 * a two's-complement machine.  Some machines produce INT64_MIN, some
+	 * produce zero, some throw an exception.  We can dodge the problem by
+	 * recognizing that division by -1 is the same as negation.
+	 */
+	if (arg2 == -1)
+	{
+		if (unlikely(arg1 == PG_INT64_MIN))
+			ereport(ERROR,
+					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+					 errmsg("bigint out of range")));
+		result = -arg1;
+		PG_RETURN_INT64(result);
+	}
+
+	/* No overflow is possible */
+
+	result = arg1 / arg2;
+
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int28pl(PG_FUNCTION_ARGS)
+{
+	int16		arg1 = PG_GETARG_INT16(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_add_s64_overflow((int64) arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int28mi(PG_FUNCTION_ARGS)
+{
+	int16		arg1 = PG_GETARG_INT16(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_sub_s64_overflow((int64) arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int28mul(PG_FUNCTION_ARGS)
+{
+	int16		arg1 = PG_GETARG_INT16(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+	int64		result;
+
+	if (unlikely(pg_mul_s64_overflow((int64) arg1, arg2, &result)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+	PG_RETURN_INT64(result);
+}
+
+Datum
+int28div(PG_FUNCTION_ARGS)
+{
+	int16		arg1 = PG_GETARG_INT16(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+
+	if (unlikely(arg2 == 0))
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_DIVISION_BY_ZERO),
+				 errmsg("division by zero")));
+		/* ensure compiler realizes we mustn't reach the division (gcc bug) */
+		PG_RETURN_NULL();
+	}
+
+	/* No overflow is possible */
+	PG_RETURN_INT64((int64) arg1 / arg2);
+}
+
+/* Binary arithmetics
+ *
+ *		int8and		- returns arg1 & arg2
+ *		int8or		- returns arg1 | arg2
+ *		int8xor		- returns arg1 # arg2
+ *		int8not		- returns ~arg1
+ *		int8shl		- returns arg1 << arg2
+ *		int8shr		- returns arg1 >> arg2
+ */
+
+Datum
+int8and(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_INT64(arg1 & arg2);
+}
+
+Datum
+int8or(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_INT64(arg1 | arg2);
+}
+
+Datum
+int8xor(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int64		arg2 = PG_GETARG_INT64(1);
+
+	PG_RETURN_INT64(arg1 ^ arg2);
+}
+
+Datum
+int8not(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+
+	PG_RETURN_INT64(~arg1);
+}
+
+Datum
+int8shl(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int32		arg2 = PG_GETARG_INT32(1);
+
+	PG_RETURN_INT64(arg1 << arg2);
+}
+
+Datum
+int8shr(PG_FUNCTION_ARGS)
+{
+	int64		arg1 = PG_GETARG_INT64(0);
+	int32		arg2 = PG_GETARG_INT32(1);
+
+	PG_RETURN_INT64(arg1 >> arg2);
+}
+
+/*----------------------------------------------------------
+ *	Conversion operators.
+ *---------------------------------------------------------*/
+
+Datum
+int48(PG_FUNCTION_ARGS)
+{
+	int32		arg = PG_GETARG_INT32(0);
+
+	PG_RETURN_INT64((int64) arg);
+}
+
+Datum
+int84(PG_FUNCTION_ARGS)
+{
+	int64		arg = PG_GETARG_INT64(0);
+
+	if (unlikely(arg < PG_INT32_MIN) || unlikely(arg > PG_INT32_MAX))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("integer out of range")));
+
+	PG_RETURN_INT32((int32) arg);
+}
+
+Datum
+int28(PG_FUNCTION_ARGS)
+{
+	int16		arg = PG_GETARG_INT16(0);
+
+	PG_RETURN_INT64((int64) arg);
+}
+
+Datum
+int82(PG_FUNCTION_ARGS)
+{
+	int64		arg = PG_GETARG_INT64(0);
+
+	if (unlikely(arg < PG_INT16_MIN) || unlikely(arg > PG_INT16_MAX))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("smallint out of range")));
+
+	PG_RETURN_INT16((int16) arg);
+}
+
+Datum
+i8tod(PG_FUNCTION_ARGS)
+{
+	int64		arg = PG_GETARG_INT64(0);
+	float8		result;
+
+	result = arg;
+
+	PG_RETURN_FLOAT8(result);
+}
+
+/* dtoi8()
+ * Convert float8 to 8-byte integer.
+ */
+Datum
+dtoi8(PG_FUNCTION_ARGS)
+{
+	float8		num = PG_GETARG_FLOAT8(0);
+
+	/*
+	 * Get rid of any fractional part in the input.  This is so we don't fail
+	 * on just-out-of-range values that would round into range.  Note
+	 * assumption that rint() will pass through a NaN or Inf unchanged.
+	 */
+	num = rint(num);
+
+	/* Range check */
+	if (unlikely(isnan(num) || !FLOAT8_FITS_IN_INT64(num)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+
+	PG_RETURN_INT64((int64) num);
+}
+
+Datum
+i8tof(PG_FUNCTION_ARGS)
+{
+	int64		arg = PG_GETARG_INT64(0);
+	float4		result;
+
+	result = arg;
+
+	PG_RETURN_FLOAT4(result);
+}
+
+/* ftoi8()
+ * Convert float4 to 8-byte integer.
+ */
+Datum
+ftoi8(PG_FUNCTION_ARGS)
+{
+	float4		num = PG_GETARG_FLOAT4(0);
+
+	/*
+	 * Get rid of any fractional part in the input.  This is so we don't fail
+	 * on just-out-of-range values that would round into range.  Note
+	 * assumption that rint() will pass through a NaN or Inf unchanged.
+	 */
+	num = rint(num);
+
+	/* Range check */
+	if (unlikely(isnan(num) || !FLOAT4_FITS_IN_INT64(num)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("bigint out of range")));
+
+	PG_RETURN_INT64((int64) num);
+}
+
+Datum
+i8tooid(PG_FUNCTION_ARGS)
+{
+	int64		arg = PG_GETARG_INT64(0);
+
+	if (unlikely(arg < 0) || unlikely(arg > PG_UINT32_MAX))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("OID out of range")));
+
+	PG_RETURN_OID((Oid) arg);
+}
+
+Datum
+oidtoi8(PG_FUNCTION_ARGS)
+{
+	Oid			arg = PG_GETARG_OID(0);
+
+	PG_RETURN_INT64((int64) arg);
+}
+
+/*
+ * non-persistent numeric series generator
+ */
+Datum
+generate_series_int8(PG_FUNCTION_ARGS)
+{
+	return generate_series_step_int8(fcinfo);
+}
+
+Datum
+generate_series_step_int8(PG_FUNCTION_ARGS)
+{
+	FuncCallContext *funcctx;
+	generate_series_fctx *fctx;
+	int64		result;
+	MemoryContext oldcontext;
+
+	/* stuff done only on the first call of the function */
+	if (SRF_IS_FIRSTCALL())
+	{
+		int64		start = PG_GETARG_INT64(0);
+		int64		finish = PG_GETARG_INT64(1);
+		int64		step = 1;
+
+		/* see if we were given an explicit step size */
+		if (PG_NARGS() == 3)
+			step = PG_GETARG_INT64(2);
+		if (step == 0)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+					 errmsg("step size cannot equal zero")));
+
+		/* 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);
+
+		/* allocate memory for user context */
+		fctx = (generate_series_fctx *) palloc(sizeof(generate_series_fctx));
+
+		/*
+		 * Use fctx to keep state from call to call. Seed current with the
+		 * original start value
+		 */
+		fctx->current = start;
+		fctx->finish = finish;
+		fctx->step = step;
+
+		funcctx->user_fctx = fctx;
+		MemoryContextSwitchTo(oldcontext);
+	}
+
+	/* stuff done on every call of the function */
+	funcctx = SRF_PERCALL_SETUP();
+
+	/*
+	 * get the saved state and use current as the result for this iteration
+	 */
+	fctx = funcctx->user_fctx;
+	result = fctx->current;
+
+	if ((fctx->step > 0 && fctx->current <= fctx->finish) ||
+		(fctx->step < 0 && fctx->current >= fctx->finish))
+	{
+		/*
+		 * Increment current in preparation for next iteration. If next-value
+		 * computation overflows, this is the final result.
+		 */
+		if (pg_add_s64_overflow(fctx->current, fctx->step, &fctx->current))
+			fctx->step = 0;
+
+		/* do when there is more left to send */
+		SRF_RETURN_NEXT(funcctx, Int64GetDatum(result));
+	}
+	else
+		/* do when there is no more left */
+		SRF_RETURN_DONE(funcctx);
+}
+
+/*
+ * Planner support function for generate_series(int8, int8 [, int8])
+ */
+Datum
+generate_series_int8_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,
+					   *arg2,
+					   *arg3;
+
+			/* We can use estimated argument values here */
+			arg1 = estimate_expression_value(req->root, linitial(args));
+			arg2 = estimate_expression_value(req->root, lsecond(args));
+			if (list_length(args) >= 3)
+				arg3 = estimate_expression_value(req->root, lthird(args));
+			else
+				arg3 = NULL;
+
+			/*
+			 * If any argument is constant NULL, we can safely assume that
+			 * zero rows are returned.  Otherwise, if they're all non-NULL
+			 * constants, we can calculate the number of rows that will be
+			 * returned.  Use double arithmetic to avoid overflow hazards.
+			 */
+			if ((IsA(arg1, Const) &&
+				 ((Const *) arg1)->constisnull) ||
+				(IsA(arg2, Const) &&
+				 ((Const *) arg2)->constisnull) ||
+				(arg3 != NULL && IsA(arg3, Const) &&
+				 ((Const *) arg3)->constisnull))
+			{
+				req->rows = 0;
+				ret = (Node *) req;
+			}
+			else if (IsA(arg1, Const) &&
+					 IsA(arg2, Const) &&
+					 (arg3 == NULL || IsA(arg3, Const)))
+			{
+				double		start,
+							finish,
+							step;
+
+				start = DatumGetInt64(((Const *) arg1)->constvalue);
+				finish = DatumGetInt64(((Const *) arg2)->constvalue);
+				step = arg3 ? DatumGetInt64(((Const *) arg3)->constvalue) : 1;
+
+				/* This equation works for either sign of step */
+				if (step != 0)
+				{
+					req->rows = floor((finish - start + step) / step);
+					ret = (Node *) req;
+				}
+			}
+		}
+	}
+
+	PG_RETURN_POINTER(ret);
+}