Expose internal function for converting int64 to numeric

Existing callers had to take complicated detours via
DirectFunctionCall1().  This simplifies a lot of code.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/42b73d2d-da12-ba9f-570a-420e0cce19d9@phystech.edu

6 files changed, 48 insertions, 128 deletions

diff --git a/src/backend/utils/adt/cash.c b/src/backend/utils/adt/cash.c
index 6515fc8ec69..d093ce80386 100644
--- a/src/backend/utils/adt/cash.c
+++ b/src/backend/utils/adt/cash.c
@@ -1042,7 +1042,7 @@ cash_numeric(PG_FUNCTION_ARGS)
 		fpoint = 2;
 
 	/* convert the integral money value to numeric */
-	result = DirectFunctionCall1(int8_numeric, Int64GetDatum(money));
+	result = NumericGetDatum(int64_to_numeric(money));
 
 	/* scale appropriately, if needed */
 	if (fpoint > 0)
@@ -1056,8 +1056,7 @@ cash_numeric(PG_FUNCTION_ARGS)
 		scale = 1;
 		for (i = 0; i < fpoint; i++)
 			scale *= 10;
-		numeric_scale = DirectFunctionCall1(int8_numeric,
-											Int64GetDatum(scale));
+		numeric_scale = NumericGetDatum(int64_to_numeric(scale));
 
 		/*
 		 * Given integral inputs approaching INT64_MAX, select_div_scale()
@@ -1107,7 +1106,7 @@ numeric_cash(PG_FUNCTION_ARGS)
 		scale *= 10;
 
 	/* multiply the input amount by scale factor */
-	numeric_scale = DirectFunctionCall1(int8_numeric, Int64GetDatum(scale));
+	numeric_scale = NumericGetDatum(int64_to_numeric(scale));
 	amount = DirectFunctionCall2(numeric_mul, amount, numeric_scale);
 
 	/* note that numeric_int8 will round to nearest integer for us */
diff --git a/src/backend/utils/adt/dbsize.c b/src/backend/utils/adt/dbsize.c
index 2320c06a9bc..7def7392b95 100644
--- a/src/backend/utils/adt/dbsize.c
+++ b/src/backend/utils/adt/dbsize.c
@@ -579,14 +579,6 @@ numeric_to_cstring(Numeric n)
 	return DatumGetCString(DirectFunctionCall1(numeric_out, d));
 }
 
-static Numeric
-int64_to_numeric(int64 v)
-{
-	Datum		d = Int64GetDatum(v);
-
-	return DatumGetNumeric(DirectFunctionCall1(int8_numeric, d));
-}
-
 static bool
 numeric_is_less(Numeric a, Numeric b)
 {
@@ -615,9 +607,9 @@ numeric_half_rounded(Numeric n)
 	Datum		two;
 	Datum		result;
 
-	zero = DirectFunctionCall1(int8_numeric, Int64GetDatum(0));
-	one = DirectFunctionCall1(int8_numeric, Int64GetDatum(1));
-	two = DirectFunctionCall1(int8_numeric, Int64GetDatum(2));
+	zero = NumericGetDatum(int64_to_numeric(0));
+	one = NumericGetDatum(int64_to_numeric(1));
+	two = NumericGetDatum(int64_to_numeric(2));
 
 	if (DatumGetBool(DirectFunctionCall2(numeric_ge, d, zero)))
 		d = DirectFunctionCall2(numeric_add, d, one);
@@ -632,12 +624,10 @@ static Numeric
 numeric_shift_right(Numeric n, unsigned count)
 {
 	Datum		d = NumericGetDatum(n);
-	Datum		divisor_int64;
 	Datum		divisor_numeric;
 	Datum		result;
 
-	divisor_int64 = Int64GetDatum((int64) (1 << count));
-	divisor_numeric = DirectFunctionCall1(int8_numeric, divisor_int64);
+	divisor_numeric = NumericGetDatum(int64_to_numeric(1 << count));
 	result = DirectFunctionCall2(numeric_div_trunc, d, divisor_numeric);
 	return DatumGetNumeric(result);
 }
@@ -832,8 +822,7 @@ pg_size_bytes(PG_FUNCTION_ARGS)
 		{
 			Numeric		mul_num;
 
-			mul_num = DatumGetNumeric(DirectFunctionCall1(int8_numeric,
-														  Int64GetDatum(multiplier)));
+			mul_num = int64_to_numeric(multiplier);
 
 			num = DatumGetNumeric(DirectFunctionCall2(numeric_mul,
 													  NumericGetDatum(mul_num),
diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index 7d09537d82b..f9aa968f098 100644
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -6070,10 +6070,8 @@ numeric_to_number(PG_FUNCTION_ARGS)
 	if (IS_MULTI(&Num))
 	{
 		Numeric		x;
-		Numeric		a = DatumGetNumeric(DirectFunctionCall1(int4_numeric,
-															Int32GetDatum(10)));
-		Numeric		b = DatumGetNumeric(DirectFunctionCall1(int4_numeric,
-															Int32GetDatum(-Num.multi)));
+		Numeric		a = int64_to_numeric(10);
+		Numeric		b = int64_to_numeric(-Num.multi);
 
 		x = DatumGetNumeric(DirectFunctionCall2(numeric_power,
 												NumericGetDatum(a),
@@ -6162,10 +6160,8 @@ numeric_to_char(PG_FUNCTION_ARGS)
 
 		if (IS_MULTI(&Num))
 		{
-			Numeric		a = DatumGetNumeric(DirectFunctionCall1(int4_numeric,
-																Int32GetDatum(10)));
-			Numeric		b = DatumGetNumeric(DirectFunctionCall1(int4_numeric,
-																Int32GetDatum(Num.multi)));
+			Numeric		a = int64_to_numeric(10);
+			Numeric		b = int64_to_numeric(Num.multi);
 
 			x = DatumGetNumeric(DirectFunctionCall2(numeric_power,
 													NumericGetDatum(a),
@@ -6339,11 +6335,8 @@ int8_to_char(PG_FUNCTION_ARGS)
 	else if (IS_EEEE(&Num))
 	{
 		/* to avoid loss of precision, must go via numeric not float8 */
-		Numeric		val;
-
-		val = DatumGetNumeric(DirectFunctionCall1(int8_numeric,
-												  Int64GetDatum(value)));
-		orgnum = numeric_out_sci(val, Num.post);
+		orgnum = numeric_out_sci(int64_to_numeric(value),
+								 Num.post);
 
 		/*
 		 * numeric_out_sci() does not emit a sign for positive numbers.  We
diff --git a/src/backend/utils/adt/jsonpath_exec.c b/src/backend/utils/adt/jsonpath_exec.c
index f146767bfc3..7403c760b48 100644
--- a/src/backend/utils/adt/jsonpath_exec.c
+++ b/src/backend/utils/adt/jsonpath_exec.c
@@ -842,9 +842,7 @@ executeItemOptUnwrapTarget(JsonPathExecContext *cxt, JsonPathItem *jsp,
 				lastjbv = hasNext ? &tmpjbv : palloc(sizeof(*lastjbv));
 
 				lastjbv->type = jbvNumeric;
-				lastjbv->val.numeric =
-					DatumGetNumeric(DirectFunctionCall1(int4_numeric,
-														Int32GetDatum(last)));
+				lastjbv->val.numeric = int64_to_numeric(last);
 
 				res = executeNextItem(cxt, jsp, &elem,
 									  lastjbv, found, hasNext);
@@ -1012,9 +1010,7 @@ executeItemOptUnwrapTarget(JsonPathExecContext *cxt, JsonPathItem *jsp,
 				jb = palloc(sizeof(*jb));
 
 				jb->type = jbvNumeric;
-				jb->val.numeric =
-					DatumGetNumeric(DirectFunctionCall1(int4_numeric,
-														Int32GetDatum(size)));
+				jb->val.numeric = int64_to_numeric(size);
 
 				res = executeNextItem(cxt, jsp, NULL, jb, found, false);
 			}
@@ -1979,8 +1975,7 @@ executeKeyValueMethod(JsonPathExecContext *cxt, JsonPathItem *jsp,
 	id += (int64) cxt->baseObject.id * INT64CONST(10000000000);
 
 	idval.type = jbvNumeric;
-	idval.val.numeric = DatumGetNumeric(DirectFunctionCall1(int8_numeric,
-															Int64GetDatum(id)));
+	idval.val.numeric = int64_to_numeric(id);
 
 	it = JsonbIteratorInit(jbc);
 
diff --git a/src/backend/utils/adt/numeric.c b/src/backend/utils/adt/numeric.c
index 69d313dd52b..27d65557dfa 100644
--- a/src/backend/utils/adt/numeric.c
+++ b/src/backend/utils/adt/numeric.c
@@ -4073,23 +4073,29 @@ numeric_trim_scale(PG_FUNCTION_ARGS)
  * ----------------------------------------------------------------------
  */
 
-
-Datum
-int4_numeric(PG_FUNCTION_ARGS)
+Numeric
+int64_to_numeric(int64 val)
 {
-	int32		val = PG_GETARG_INT32(0);
 	Numeric		res;
 	NumericVar	result;
 
 	init_var(&result);
 
-	int64_to_numericvar((int64) val, &result);
+	int64_to_numericvar(val, &result);
 
 	res = make_result(&result);
 
 	free_var(&result);
 
-	PG_RETURN_NUMERIC(res);
+	return res;
+}
+
+Datum
+int4_numeric(PG_FUNCTION_ARGS)
+{
+	int32		val = PG_GETARG_INT32(0);
+
+	PG_RETURN_NUMERIC(int64_to_numeric(val));
 }
 
 int32
@@ -4174,18 +4180,8 @@ Datum
 int8_numeric(PG_FUNCTION_ARGS)
 {
 	int64		val = PG_GETARG_INT64(0);
-	Numeric		res;
-	NumericVar	result;
 
-	init_var(&result);
-
-	int64_to_numericvar(val, &result);
-
-	res = make_result(&result);
-
-	free_var(&result);
-
-	PG_RETURN_NUMERIC(res);
+	PG_RETURN_NUMERIC(int64_to_numeric(val));
 }
 
 
@@ -4224,18 +4220,8 @@ Datum
 int2_numeric(PG_FUNCTION_ARGS)
 {
 	int16		val = PG_GETARG_INT16(0);
-	Numeric		res;
-	NumericVar	result;
-
-	init_var(&result);
-
-	int64_to_numericvar((int64) val, &result);
-
-	res = make_result(&result);
 
-	free_var(&result);
-
-	PG_RETURN_NUMERIC(res);
+	PG_RETURN_NUMERIC(int64_to_numeric(val));
 }
 
 
@@ -5290,11 +5276,7 @@ int2_accum(PG_FUNCTION_ARGS)
 #ifdef HAVE_INT128
 		do_int128_accum(state, (int128) PG_GETARG_INT16(1));
 #else
-		Numeric		newval;
-
-		newval = DatumGetNumeric(DirectFunctionCall1(int2_numeric,
-													 PG_GETARG_DATUM(1)));
-		do_numeric_accum(state, newval);
+		do_numeric_accum(state, int64_to_numeric(PG_GETARG_INT16(1)));
 #endif
 	}
 
@@ -5317,11 +5299,7 @@ int4_accum(PG_FUNCTION_ARGS)
 #ifdef HAVE_INT128
 		do_int128_accum(state, (int128) PG_GETARG_INT32(1));
 #else
-		Numeric		newval;
-
-		newval = DatumGetNumeric(DirectFunctionCall1(int4_numeric,
-													 PG_GETARG_DATUM(1)));
-		do_numeric_accum(state, newval);
+		do_numeric_accum(state, int64_to_numeric(PG_GETARG_INT32(1)));
 #endif
 	}
 
@@ -5340,13 +5318,7 @@ int8_accum(PG_FUNCTION_ARGS)
 		state = makeNumericAggState(fcinfo, true);
 
 	if (!PG_ARGISNULL(1))
-	{
-		Numeric		newval;
-
-		newval = DatumGetNumeric(DirectFunctionCall1(int8_numeric,
-													 PG_GETARG_DATUM(1)));
-		do_numeric_accum(state, newval);
-	}
+		do_numeric_accum(state, int64_to_numeric(PG_GETARG_INT64(1)));
 
 	PG_RETURN_POINTER(state);
 }
@@ -5570,11 +5542,7 @@ int8_avg_accum(PG_FUNCTION_ARGS)
 #ifdef HAVE_INT128
 		do_int128_accum(state, (int128) PG_GETARG_INT64(1));
 #else
-		Numeric		newval;
-
-		newval = DatumGetNumeric(DirectFunctionCall1(int8_numeric,
-													 PG_GETARG_DATUM(1)));
-		do_numeric_accum(state, newval);
+		do_numeric_accum(state, int64_to_numeric(PG_GETARG_INT64(1)));
 #endif
 	}
 
@@ -5767,13 +5735,8 @@ int2_accum_inv(PG_FUNCTION_ARGS)
 #ifdef HAVE_INT128
 		do_int128_discard(state, (int128) PG_GETARG_INT16(1));
 #else
-		Numeric		newval;
-
-		newval = DatumGetNumeric(DirectFunctionCall1(int2_numeric,
-													 PG_GETARG_DATUM(1)));
-
 		/* Should never fail, all inputs have dscale 0 */
-		if (!do_numeric_discard(state, newval))
+		if (!do_numeric_discard(state, int64_to_numeric(PG_GETARG_INT16(1))))
 			elog(ERROR, "do_numeric_discard failed unexpectedly");
 #endif
 	}
@@ -5797,13 +5760,8 @@ int4_accum_inv(PG_FUNCTION_ARGS)
 #ifdef HAVE_INT128
 		do_int128_discard(state, (int128) PG_GETARG_INT32(1));
 #else
-		Numeric		newval;
-
-		newval = DatumGetNumeric(DirectFunctionCall1(int4_numeric,
-													 PG_GETARG_DATUM(1)));
-
 		/* Should never fail, all inputs have dscale 0 */
-		if (!do_numeric_discard(state, newval))
+		if (!do_numeric_discard(state, int64_to_numeric(PG_GETARG_INT32(1))))
 			elog(ERROR, "do_numeric_discard failed unexpectedly");
 #endif
 	}
@@ -5824,13 +5782,8 @@ int8_accum_inv(PG_FUNCTION_ARGS)
 
 	if (!PG_ARGISNULL(1))
 	{
-		Numeric		newval;
-
-		newval = DatumGetNumeric(DirectFunctionCall1(int8_numeric,
-													 PG_GETARG_DATUM(1)));
-
 		/* Should never fail, all inputs have dscale 0 */
-		if (!do_numeric_discard(state, newval))
+		if (!do_numeric_discard(state, int64_to_numeric(PG_GETARG_INT64(1))))
 			elog(ERROR, "do_numeric_discard failed unexpectedly");
 	}
 
@@ -5853,13 +5806,8 @@ int8_avg_accum_inv(PG_FUNCTION_ARGS)
 #ifdef HAVE_INT128
 		do_int128_discard(state, (int128) PG_GETARG_INT64(1));
 #else
-		Numeric		newval;
-
-		newval = DatumGetNumeric(DirectFunctionCall1(int8_numeric,
-													 PG_GETARG_DATUM(1)));
-
 		/* Should never fail, all inputs have dscale 0 */
-		if (!do_numeric_discard(state, newval))
+		if (!do_numeric_discard(state, int64_to_numeric(PG_GETARG_INT64(1))))
 			elog(ERROR, "do_numeric_discard failed unexpectedly");
 #endif
 	}
@@ -5914,8 +5862,7 @@ numeric_poly_avg(PG_FUNCTION_ARGS)
 
 	int128_to_numericvar(state->sumX, &result);
 
-	countd = DirectFunctionCall1(int8_numeric,
-								 Int64GetDatumFast(state->N));
+	countd = NumericGetDatum(int64_to_numeric(state->N));
 	sumd = NumericGetDatum(make_result(&result));
 
 	free_var(&result);
@@ -5951,7 +5898,7 @@ numeric_avg(PG_FUNCTION_ARGS)
 	if (state->nInfcount > 0)
 		PG_RETURN_NUMERIC(make_result(&const_ninf));
 
-	N_datum = DirectFunctionCall1(int8_numeric, Int64GetDatum(state->N));
+	N_datum = NumericGetDatum(int64_to_numeric(state->N));
 
 	init_var(&sumX_var);
 	accum_sum_final(&state->sumX, &sumX_var);
@@ -6411,7 +6358,6 @@ Datum
 int8_sum(PG_FUNCTION_ARGS)
 {
 	Numeric		oldsum;
-	Datum		newval;
 
 	if (PG_ARGISNULL(0))
 	{
@@ -6419,8 +6365,7 @@ int8_sum(PG_FUNCTION_ARGS)
 		if (PG_ARGISNULL(1))
 			PG_RETURN_NULL();	/* still no non-null */
 		/* This is the first non-null input. */
-		newval = DirectFunctionCall1(int8_numeric, PG_GETARG_DATUM(1));
-		PG_RETURN_DATUM(newval);
+		PG_RETURN_NUMERIC(int64_to_numeric(PG_GETARG_INT64(1)));
 	}
 
 	/*
@@ -6436,10 +6381,9 @@ int8_sum(PG_FUNCTION_ARGS)
 		PG_RETURN_NUMERIC(oldsum);
 
 	/* OK to do the addition. */
-	newval = DirectFunctionCall1(int8_numeric, PG_GETARG_DATUM(1));
-
 	PG_RETURN_DATUM(DirectFunctionCall2(numeric_add,
-										NumericGetDatum(oldsum), newval));
+										NumericGetDatum(oldsum),
+										NumericGetDatum(int64_to_numeric(PG_GETARG_INT64(1)))));
 }
 
 
@@ -6618,10 +6562,8 @@ int8_avg(PG_FUNCTION_ARGS)
 	if (transdata->count == 0)
 		PG_RETURN_NULL();
 
-	countd = DirectFunctionCall1(int8_numeric,
-								 Int64GetDatumFast(transdata->count));
-	sumd = DirectFunctionCall1(int8_numeric,
-							   Int64GetDatumFast(transdata->sum));
+	countd = NumericGetDatum(int64_to_numeric(transdata->count));
+	sumd = NumericGetDatum(int64_to_numeric(transdata->sum));
 
 	PG_RETURN_DATUM(DirectFunctionCall2(numeric_div, sumd, countd));
 }
diff --git a/src/include/utils/numeric.h b/src/include/utils/numeric.h
index 0b7d4ba3c4b..2a768b9a04a 100644
--- a/src/include/utils/numeric.h
+++ b/src/include/utils/numeric.h
@@ -62,6 +62,8 @@ int32		numeric_maximum_size(int32 typmod);
 extern char *numeric_out_sci(Numeric num, int scale);
 extern char *numeric_normalize(Numeric num);
 
+extern Numeric int64_to_numeric(int64 val);
+
 extern Numeric numeric_add_opt_error(Numeric num1, Numeric num2,
 									 bool *have_error);
 extern Numeric numeric_sub_opt_error(Numeric num1, Numeric num2,