gh-112919: Speed-up datetime, date and time.replace() (GH-112921)

Use argument clinic and call new_* functions directly. This speeds up
these functions 6x to 7.5x when calling with keyword arguments.

Include/internal/pycore_global_objects_fini_generated.h

@@ -876,6 +876,7 @@ _PyStaticObjects_CheckRefcnt(PyInterpreterState *interp) {
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(d));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(data));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(database));
+    _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(day));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(decode));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(decoder));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(default));
@@ -945,6 +946,7 @@ _PyStaticObjects_CheckRefcnt(PyInterpreterState *interp) {
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(fix_imports));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(flags));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(flush));
+    _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(fold));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(follow_symlinks));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(format));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(from_param));
@@ -975,6 +977,7 @@ _PyStaticObjects_CheckRefcnt(PyInterpreterState *interp) {
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(headers));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(hi));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(hook));
+    _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(hour));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(id));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(ident));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(identity_hint));
@@ -1059,11 +1062,14 @@ _PyStaticObjects_CheckRefcnt(PyInterpreterState *interp) {
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(metaclass));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(metadata));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(method));
+    _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(microsecond));
+    _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(minute));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(mod));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(mode));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(module));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(module_globals));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(modules));
+    _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(month));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(mro));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(msg));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(mycmp));
@@ -1168,6 +1174,7 @@ _PyStaticObjects_CheckRefcnt(PyInterpreterState *interp) {
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(salt));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(sched_priority));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(scheduler));
+    _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(second));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(seek));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(seekable));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(selectors));
@@ -1244,6 +1251,7 @@ _PyStaticObjects_CheckRefcnt(PyInterpreterState *interp) {
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(type));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(type_params));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(tz));
+    _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(tzinfo));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(tzname));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(uid));
     _PyStaticObject_CheckRefcnt((PyObject *)&_Py_ID(unlink));

Include/internal/pycore_global_strings.h

@@ -365,6 +365,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(d)
         STRUCT_FOR_ID(data)
         STRUCT_FOR_ID(database)
+        STRUCT_FOR_ID(day)
         STRUCT_FOR_ID(decode)
         STRUCT_FOR_ID(decoder)
         STRUCT_FOR_ID(default)
@@ -434,6 +435,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(fix_imports)
         STRUCT_FOR_ID(flags)
         STRUCT_FOR_ID(flush)
+        STRUCT_FOR_ID(fold)
         STRUCT_FOR_ID(follow_symlinks)
         STRUCT_FOR_ID(format)
         STRUCT_FOR_ID(from_param)
@@ -464,6 +466,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(headers)
         STRUCT_FOR_ID(hi)
         STRUCT_FOR_ID(hook)
+        STRUCT_FOR_ID(hour)
         STRUCT_FOR_ID(id)
         STRUCT_FOR_ID(ident)
         STRUCT_FOR_ID(identity_hint)
@@ -548,11 +551,14 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(metaclass)
         STRUCT_FOR_ID(metadata)
         STRUCT_FOR_ID(method)
+        STRUCT_FOR_ID(microsecond)
+        STRUCT_FOR_ID(minute)
         STRUCT_FOR_ID(mod)
         STRUCT_FOR_ID(mode)
         STRUCT_FOR_ID(module)
         STRUCT_FOR_ID(module_globals)
         STRUCT_FOR_ID(modules)
+        STRUCT_FOR_ID(month)
         STRUCT_FOR_ID(mro)
         STRUCT_FOR_ID(msg)
         STRUCT_FOR_ID(mycmp)
@@ -657,6 +663,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(salt)
         STRUCT_FOR_ID(sched_priority)
         STRUCT_FOR_ID(scheduler)
+        STRUCT_FOR_ID(second)
         STRUCT_FOR_ID(seek)
         STRUCT_FOR_ID(seekable)
         STRUCT_FOR_ID(selectors)
@@ -733,6 +740,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(type)
         STRUCT_FOR_ID(type_params)
         STRUCT_FOR_ID(tz)
+        STRUCT_FOR_ID(tzinfo)
         STRUCT_FOR_ID(tzname)
         STRUCT_FOR_ID(uid)
         STRUCT_FOR_ID(unlink)

Include/internal/pycore_runtime_init_generated.h

@@ -874,6 +874,7 @@ extern "C" {
     INIT_ID(d), \
     INIT_ID(data), \
     INIT_ID(database), \
+    INIT_ID(day), \
     INIT_ID(decode), \
     INIT_ID(decoder), \
     INIT_ID(default), \
@@ -943,6 +944,7 @@ extern "C" {
     INIT_ID(fix_imports), \
     INIT_ID(flags), \
     INIT_ID(flush), \
+    INIT_ID(fold), \
     INIT_ID(follow_symlinks), \
     INIT_ID(format), \
     INIT_ID(from_param), \
@@ -973,6 +975,7 @@ extern "C" {
     INIT_ID(headers), \
     INIT_ID(hi), \
     INIT_ID(hook), \
+    INIT_ID(hour), \
     INIT_ID(id), \
     INIT_ID(ident), \
     INIT_ID(identity_hint), \
@@ -1057,11 +1060,14 @@ extern "C" {
     INIT_ID(metaclass), \
     INIT_ID(metadata), \
     INIT_ID(method), \
+    INIT_ID(microsecond), \
+    INIT_ID(minute), \
     INIT_ID(mod), \
     INIT_ID(mode), \
     INIT_ID(module), \
     INIT_ID(module_globals), \
     INIT_ID(modules), \
+    INIT_ID(month), \
     INIT_ID(mro), \
     INIT_ID(msg), \
     INIT_ID(mycmp), \
@@ -1166,6 +1172,7 @@ extern "C" {
     INIT_ID(salt), \
     INIT_ID(sched_priority), \
     INIT_ID(scheduler), \
+    INIT_ID(second), \
     INIT_ID(seek), \
     INIT_ID(seekable), \
     INIT_ID(selectors), \
@@ -1242,6 +1249,7 @@ extern "C" {
     INIT_ID(type), \
     INIT_ID(type_params), \
     INIT_ID(tz), \
+    INIT_ID(tzinfo), \
     INIT_ID(tzname), \
     INIT_ID(uid), \
     INIT_ID(unlink), \

Include/internal/pycore_unicodeobject_generated.h

@@ -936,6 +936,9 @@ _PyUnicode_InitStaticStrings(PyInterpreterState *interp) {
     string = &_Py_ID(database);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
+    string = &_Py_ID(day);
+    assert(_PyUnicode_CheckConsistency(string, 1));
+    _PyUnicode_InternInPlace(interp, &string);
     string = &_Py_ID(decode);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
@@ -1143,6 +1146,9 @@ _PyUnicode_InitStaticStrings(PyInterpreterState *interp) {
     string = &_Py_ID(flush);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
+    string = &_Py_ID(fold);
+    assert(_PyUnicode_CheckConsistency(string, 1));
+    _PyUnicode_InternInPlace(interp, &string);
     string = &_Py_ID(follow_symlinks);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
@@ -1233,6 +1239,9 @@ _PyUnicode_InitStaticStrings(PyInterpreterState *interp) {
     string = &_Py_ID(hook);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
+    string = &_Py_ID(hour);
+    assert(_PyUnicode_CheckConsistency(string, 1));
+    _PyUnicode_InternInPlace(interp, &string);
     string = &_Py_ID(id);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
@@ -1485,6 +1494,12 @@ _PyUnicode_InitStaticStrings(PyInterpreterState *interp) {
     string = &_Py_ID(method);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
+    string = &_Py_ID(microsecond);
+    assert(_PyUnicode_CheckConsistency(string, 1));
+    _PyUnicode_InternInPlace(interp, &string);
+    string = &_Py_ID(minute);
+    assert(_PyUnicode_CheckConsistency(string, 1));
+    _PyUnicode_InternInPlace(interp, &string);
     string = &_Py_ID(mod);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
@@ -1500,6 +1515,9 @@ _PyUnicode_InitStaticStrings(PyInterpreterState *interp) {
     string = &_Py_ID(modules);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
+    string = &_Py_ID(month);
+    assert(_PyUnicode_CheckConsistency(string, 1));
+    _PyUnicode_InternInPlace(interp, &string);
     string = &_Py_ID(mro);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
@@ -1812,6 +1830,9 @@ _PyUnicode_InitStaticStrings(PyInterpreterState *interp) {
     string = &_Py_ID(scheduler);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
+    string = &_Py_ID(second);
+    assert(_PyUnicode_CheckConsistency(string, 1));
+    _PyUnicode_InternInPlace(interp, &string);
     string = &_Py_ID(seek);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
@@ -2040,6 +2061,9 @@ _PyUnicode_InitStaticStrings(PyInterpreterState *interp) {
     string = &_Py_ID(tz);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);
+    string = &_Py_ID(tzinfo);
+    assert(_PyUnicode_CheckConsistency(string, 1));
+    _PyUnicode_InternInPlace(interp, &string);
     string = &_Py_ID(tzname);
     assert(_PyUnicode_CheckConsistency(string, 1));
     _PyUnicode_InternInPlace(interp, &string);

Misc/NEWS.d/next/Library/2023-12-09-23-31-17.gh-issue-112919.S5k9QN.rst

@@ -0,0 +1,2 @@
+Speed-up :func:`datetime.datetime.replace`, :func:`datetime.date.replace` and
+:func:`datetime.time.replace`.

Modules/_datetimemodule.c

@@ -61,16 +61,6 @@ static datetime_state _datetime_global_state;
 
 #define STATIC_STATE() (&_datetime_global_state)
 
-/*[clinic input]
-module datetime
-class datetime.datetime "PyDateTime_DateTime *" "&PyDateTime_DateTimeType"
-class datetime.date "PyDateTime_Date *" "&PyDateTime_DateType"
-class datetime.IsoCalendarDate "PyDateTime_IsoCalendarDate *" "&PyDateTime_IsoCalendarDateType"
-[clinic start generated code]*/
-/*[clinic end generated code: output=da39a3ee5e6b4b0d input=81bec0fa19837f63]*/
-
-#include "clinic/_datetimemodule.c.h"
-
 /* We require that C int be at least 32 bits, and use int virtually
  * everywhere.  In just a few cases we use a temp long, where a Python
  * API returns a C long.  In such cases, we have to ensure that the
@@ -161,6 +151,17 @@ static PyTypeObject PyDateTime_TimeZoneType;
 
 static int check_tzinfo_subclass(PyObject *p);
 
+/*[clinic input]
+module datetime
+class datetime.datetime "PyDateTime_DateTime *" "&PyDateTime_DateTimeType"
+class datetime.date "PyDateTime_Date *" "&PyDateTime_DateType"
+class datetime.time "PyDateTime_Time *" "&PyDateTime_TimeType"
+class datetime.IsoCalendarDate "PyDateTime_IsoCalendarDate *" "&PyDateTime_IsoCalendarDateType"
+[clinic start generated code]*/
+/*[clinic end generated code: output=da39a3ee5e6b4b0d input=6f65a48dd22fa40f]*/
+
+#include "clinic/_datetimemodule.c.h"
+
 
 /* ---------------------------------------------------------------------------
  * Math utilities.
@@ -3466,24 +3467,22 @@ date_timetuple(PyDateTime_Date *self, PyObject *Py_UNUSED(ignored))
                              0, 0, 0, -1);
 }
 
-static PyObject *
+/*[clinic input]
-date_replace(PyDateTime_Date *self, PyObject *args, PyObject *kw)
+datetime.date.replace
-{
-    PyObject *clone;
-    PyObject *tuple;
-    int year = GET_YEAR(self);
-    int month = GET_MONTH(self);
-    int day = GET_DAY(self);
 
-    if (! PyArg_ParseTupleAndKeywords(args, kw, "|iii:replace", date_kws,
+    year: int(c_default="GET_YEAR(self)") = unchanged
-                                      &year, &month, &day))
+    month: int(c_default="GET_MONTH(self)") = unchanged
-        return NULL;
+    day: int(c_default="GET_DAY(self)") = unchanged
-    tuple = Py_BuildValue("iii", year, month, day);
+
-    if (tuple == NULL)
+Return date with new specified fields.
-        return NULL;
+[clinic start generated code]*/
-    clone = date_new(Py_TYPE(self), tuple, NULL);
+
-    Py_DECREF(tuple);
+static PyObject *
-    return clone;
+datetime_date_replace_impl(PyDateTime_Date *self, int year, int month,
+                           int day)
+/*[clinic end generated code: output=2a9430d1e6318aeb input=0d1f02685b3e90f6]*/
+{
+    return new_date_ex(year, month, day, Py_TYPE(self));
 }
 
 static Py_hash_t
@@ -3596,10 +3595,9 @@ static PyMethodDef date_methods[] = {
      PyDoc_STR("Return the day of the week represented by the date.\n"
                "Monday == 0 ... Sunday == 6")},
 
-    {"replace",     _PyCFunction_CAST(date_replace),      METH_VARARGS | METH_KEYWORDS,
+    DATETIME_DATE_REPLACE_METHODDEF
-     PyDoc_STR("Return date with new specified fields.")},
 
-    {"__replace__", _PyCFunction_CAST(date_replace),      METH_VARARGS | METH_KEYWORDS},
+    {"__replace__", _PyCFunction_CAST(datetime_date_replace), METH_FASTCALL | METH_KEYWORDS},
 
     {"__reduce__", (PyCFunction)date_reduce,        METH_NOARGS,
      PyDoc_STR("__reduce__() -> (cls, state)")},
@@ -4573,36 +4571,28 @@ time_hash(PyDateTime_Time *self)
     return self->hashcode;
 }
 
-static PyObject *
+/*[clinic input]
-time_replace(PyDateTime_Time *self, PyObject *args, PyObject *kw)
+datetime.time.replace
-{
-    PyObject *clone;
-    PyObject *tuple;
-    int hh = TIME_GET_HOUR(self);
-    int mm = TIME_GET_MINUTE(self);
-    int ss = TIME_GET_SECOND(self);
-    int us = TIME_GET_MICROSECOND(self);
-    PyObject *tzinfo = HASTZINFO(self) ? self->tzinfo : Py_None;
-    int fold = TIME_GET_FOLD(self);
 
-    if (! PyArg_ParseTupleAndKeywords(args, kw, "|iiiiO$i:replace",
+    hour: int(c_default="TIME_GET_HOUR(self)") = unchanged
-                                      time_kws,
+    minute: int(c_default="TIME_GET_MINUTE(self)") = unchanged
-                                      &hh, &mm, &ss, &us, &tzinfo, &fold))
+    second: int(c_default="TIME_GET_SECOND(self)") = unchanged
-        return NULL;
+    microsecond: int(c_default="TIME_GET_MICROSECOND(self)") = unchanged
-    if (fold != 0 && fold != 1) {
+    tzinfo: object(c_default="HASTZINFO(self) ? self->tzinfo : Py_None") = unchanged
-        PyErr_SetString(PyExc_ValueError,
+    *
-                        "fold must be either 0 or 1");
+    fold: int(c_default="TIME_GET_FOLD(self)") = unchanged
-        return NULL;
+
-    }
+Return time with new specified fields.
-    tuple = Py_BuildValue("iiiiO", hh, mm, ss, us, tzinfo);
+[clinic start generated code]*/
-    if (tuple == NULL)
+
-        return NULL;
+static PyObject *
-    clone = time_new(Py_TYPE(self), tuple, NULL);
+datetime_time_replace_impl(PyDateTime_Time *self, int hour, int minute,
-    if (clone != NULL) {
+                           int second, int microsecond, PyObject *tzinfo,
-        TIME_SET_FOLD(clone, fold);
+                           int fold)
-    }
+/*[clinic end generated code: output=0b89a44c299e4f80 input=9b6a35b1e704b0ca]*/
-    Py_DECREF(tuple);
+{
-    return clone;
+    return new_time_ex2(hour, minute, second, microsecond, tzinfo, fold,
+                        Py_TYPE(self));
 }
 
 static PyObject *
@@ -4732,10 +4722,9 @@ static PyMethodDef time_methods[] = {
     {"dst",             (PyCFunction)time_dst,          METH_NOARGS,
      PyDoc_STR("Return self.tzinfo.dst(self).")},
 
-    {"replace",     _PyCFunction_CAST(time_replace),          METH_VARARGS | METH_KEYWORDS,
+    DATETIME_TIME_REPLACE_METHODDEF
-     PyDoc_STR("Return time with new specified fields.")},
 
-    {"__replace__", _PyCFunction_CAST(time_replace),          METH_VARARGS | METH_KEYWORDS},
+    {"__replace__", _PyCFunction_CAST(datetime_time_replace), METH_FASTCALL | METH_KEYWORDS},
 
      {"fromisoformat", (PyCFunction)time_fromisoformat, METH_O | METH_CLASS,
      PyDoc_STR("string -> time from a string in ISO 8601 format")},
@@ -6042,40 +6031,32 @@ datetime_hash(PyDateTime_DateTime *self)
     return self->hashcode;
 }
 
-static PyObject *
+/*[clinic input]
-datetime_replace(PyDateTime_DateTime *self, PyObject *args, PyObject *kw)
+datetime.datetime.replace
-{
-    PyObject *clone;
-    PyObject *tuple;
-    int y = GET_YEAR(self);
-    int m = GET_MONTH(self);
-    int d = GET_DAY(self);
-    int hh = DATE_GET_HOUR(self);
-    int mm = DATE_GET_MINUTE(self);
-    int ss = DATE_GET_SECOND(self);
-    int us = DATE_GET_MICROSECOND(self);
-    PyObject *tzinfo = HASTZINFO(self) ? self->tzinfo : Py_None;
-    int fold = DATE_GET_FOLD(self);
 
-    if (! PyArg_ParseTupleAndKeywords(args, kw, "|iiiiiiiO$i:replace",
+    year: int(c_default="GET_YEAR(self)") = unchanged
-                                      datetime_kws,
+    month: int(c_default="GET_MONTH(self)") = unchanged
-                                      &y, &m, &d, &hh, &mm, &ss, &us,
+    day: int(c_default="GET_DAY(self)") = unchanged
-                                      &tzinfo, &fold))
+    hour: int(c_default="DATE_GET_HOUR(self)") = unchanged
-        return NULL;
+    minute: int(c_default="DATE_GET_MINUTE(self)") = unchanged
-    if (fold != 0 && fold != 1) {
+    second: int(c_default="DATE_GET_SECOND(self)") = unchanged
-        PyErr_SetString(PyExc_ValueError,
+    microsecond: int(c_default="DATE_GET_MICROSECOND(self)") = unchanged
-                        "fold must be either 0 or 1");
+    tzinfo: object(c_default="HASTZINFO(self) ? self->tzinfo : Py_None") = unchanged
-        return NULL;
+    *
-    }
+    fold: int(c_default="DATE_GET_FOLD(self)") = unchanged
-    tuple = Py_BuildValue("iiiiiiiO", y, m, d, hh, mm, ss, us, tzinfo);
+
-    if (tuple == NULL)
+Return datetime with new specified fields.
-        return NULL;
+[clinic start generated code]*/
-    clone = datetime_new(Py_TYPE(self), tuple, NULL);
+
-    if (clone != NULL) {
+static PyObject *
-        DATE_SET_FOLD(clone, fold);
+datetime_datetime_replace_impl(PyDateTime_DateTime *self, int year,
-    }
+                               int month, int day, int hour, int minute,
-    Py_DECREF(tuple);
+                               int second, int microsecond, PyObject *tzinfo,
-    return clone;
+                               int fold)
+/*[clinic end generated code: output=00bc96536833fddb input=9b38253d56d9bcad]*/
+{
+    return new_datetime_ex2(year, month, day, hour, minute, second,
+                            microsecond, tzinfo, fold, Py_TYPE(self));
 }
 
 static PyObject *
@@ -6597,10 +6578,9 @@ static PyMethodDef datetime_methods[] = {
     {"dst",             (PyCFunction)datetime_dst, METH_NOARGS,
      PyDoc_STR("Return self.tzinfo.dst(self).")},
 
-    {"replace",     _PyCFunction_CAST(datetime_replace),      METH_VARARGS | METH_KEYWORDS,
+    DATETIME_DATETIME_REPLACE_METHODDEF
-     PyDoc_STR("Return datetime with new specified fields.")},
 
-    {"__replace__", _PyCFunction_CAST(datetime_replace),      METH_VARARGS | METH_KEYWORDS},
+    {"__replace__", _PyCFunction_CAST(datetime_datetime_replace), METH_FASTCALL | METH_KEYWORDS},
 
     {"astimezone",  _PyCFunction_CAST(datetime_astimezone), METH_VARARGS | METH_KEYWORDS,
      PyDoc_STR("tz -> convert to local time in new timezone tz\n")},

Modules/clinic/_datetimemodule.c.h

@@ -82,6 +82,207 @@ exit:
     return return_value;
 }
 
+PyDoc_STRVAR(datetime_date_replace__doc__,
+"replace($self, /, year=unchanged, month=unchanged, day=unchanged)\n"
+"--\n"
+"\n"
+"Return date with new specified fields.");
+
+#define DATETIME_DATE_REPLACE_METHODDEF    \
+    {"replace", _PyCFunction_CAST(datetime_date_replace), METH_FASTCALL|METH_KEYWORDS, datetime_date_replace__doc__},
+
+static PyObject *
+datetime_date_replace_impl(PyDateTime_Date *self, int year, int month,
+                           int day);
+
+static PyObject *
+datetime_date_replace(PyDateTime_Date *self, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
+{
+    PyObject *return_value = NULL;
+    #if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE)
+
+    #define NUM_KEYWORDS 3
+    static struct {
+        PyGC_Head _this_is_not_used;
+        PyObject_VAR_HEAD
+        PyObject *ob_item[NUM_KEYWORDS];
+    } _kwtuple = {
+        .ob_base = PyVarObject_HEAD_INIT(&PyTuple_Type, NUM_KEYWORDS)
+        .ob_item = { &_Py_ID(year), &_Py_ID(month), &_Py_ID(day), },
+    };
+    #undef NUM_KEYWORDS
+    #define KWTUPLE (&_kwtuple.ob_base.ob_base)
+
+    #else  // !Py_BUILD_CORE
+    #  define KWTUPLE NULL
+    #endif  // !Py_BUILD_CORE
+
+    static const char * const _keywords[] = {"year", "month", "day", NULL};
+    static _PyArg_Parser _parser = {
+        .keywords = _keywords,
+        .fname = "replace",
+        .kwtuple = KWTUPLE,
+    };
+    #undef KWTUPLE
+    PyObject *argsbuf[3];
+    Py_ssize_t noptargs = nargs + (kwnames ? PyTuple_GET_SIZE(kwnames) : 0) - 0;
+    int year = GET_YEAR(self);
+    int month = GET_MONTH(self);
+    int day = GET_DAY(self);
+
+    args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 0, 3, 0, argsbuf);
+    if (!args) {
+        goto exit;
+    }
+    if (!noptargs) {
+        goto skip_optional_pos;
+    }
+    if (args[0]) {
+        year = PyLong_AsInt(args[0]);
+        if (year == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[1]) {
+        month = PyLong_AsInt(args[1]);
+        if (month == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    day = PyLong_AsInt(args[2]);
+    if (day == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional_pos:
+    return_value = datetime_date_replace_impl(self, year, month, day);
+
+exit:
+    return return_value;
+}
+
+PyDoc_STRVAR(datetime_time_replace__doc__,
+"replace($self, /, hour=unchanged, minute=unchanged, second=unchanged,\n"
+"        microsecond=unchanged, tzinfo=unchanged, *, fold=unchanged)\n"
+"--\n"
+"\n"
+"Return time with new specified fields.");
+
+#define DATETIME_TIME_REPLACE_METHODDEF    \
+    {"replace", _PyCFunction_CAST(datetime_time_replace), METH_FASTCALL|METH_KEYWORDS, datetime_time_replace__doc__},
+
+static PyObject *
+datetime_time_replace_impl(PyDateTime_Time *self, int hour, int minute,
+                           int second, int microsecond, PyObject *tzinfo,
+                           int fold);
+
+static PyObject *
+datetime_time_replace(PyDateTime_Time *self, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
+{
+    PyObject *return_value = NULL;
+    #if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE)
+
+    #define NUM_KEYWORDS 6
+    static struct {
+        PyGC_Head _this_is_not_used;
+        PyObject_VAR_HEAD
+        PyObject *ob_item[NUM_KEYWORDS];
+    } _kwtuple = {
+        .ob_base = PyVarObject_HEAD_INIT(&PyTuple_Type, NUM_KEYWORDS)
+        .ob_item = { &_Py_ID(hour), &_Py_ID(minute), &_Py_ID(second), &_Py_ID(microsecond), &_Py_ID(tzinfo), &_Py_ID(fold), },
+    };
+    #undef NUM_KEYWORDS
+    #define KWTUPLE (&_kwtuple.ob_base.ob_base)
+
+    #else  // !Py_BUILD_CORE
+    #  define KWTUPLE NULL
+    #endif  // !Py_BUILD_CORE
+
+    static const char * const _keywords[] = {"hour", "minute", "second", "microsecond", "tzinfo", "fold", NULL};
+    static _PyArg_Parser _parser = {
+        .keywords = _keywords,
+        .fname = "replace",
+        .kwtuple = KWTUPLE,
+    };
+    #undef KWTUPLE
+    PyObject *argsbuf[6];
+    Py_ssize_t noptargs = nargs + (kwnames ? PyTuple_GET_SIZE(kwnames) : 0) - 0;
+    int hour = TIME_GET_HOUR(self);
+    int minute = TIME_GET_MINUTE(self);
+    int second = TIME_GET_SECOND(self);
+    int microsecond = TIME_GET_MICROSECOND(self);
+    PyObject *tzinfo = HASTZINFO(self) ? self->tzinfo : Py_None;
+    int fold = TIME_GET_FOLD(self);
+
+    args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 0, 5, 0, argsbuf);
+    if (!args) {
+        goto exit;
+    }
+    if (!noptargs) {
+        goto skip_optional_pos;
+    }
+    if (args[0]) {
+        hour = PyLong_AsInt(args[0]);
+        if (hour == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[1]) {
+        minute = PyLong_AsInt(args[1]);
+        if (minute == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[2]) {
+        second = PyLong_AsInt(args[2]);
+        if (second == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[3]) {
+        microsecond = PyLong_AsInt(args[3]);
+        if (microsecond == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[4]) {
+        tzinfo = args[4];
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+skip_optional_pos:
+    if (!noptargs) {
+        goto skip_optional_kwonly;
+    }
+    fold = PyLong_AsInt(args[5]);
+    if (fold == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional_kwonly:
+    return_value = datetime_time_replace_impl(self, hour, minute, second, microsecond, tzinfo, fold);
+
+exit:
+    return return_value;
+}
+
 PyDoc_STRVAR(datetime_datetime_now__doc__,
 "now($type, /, tz=None)\n"
 "--\n"
@@ -146,4 +347,153 @@ skip_optional_pos:
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=562813dd3e164794 input=a9049054013a1b77]*/
+
+PyDoc_STRVAR(datetime_datetime_replace__doc__,
+"replace($self, /, year=unchanged, month=unchanged, day=unchanged,\n"
+"        hour=unchanged, minute=unchanged, second=unchanged,\n"
+"        microsecond=unchanged, tzinfo=unchanged, *, fold=unchanged)\n"
+"--\n"
+"\n"
+"Return datetime with new specified fields.");
+
+#define DATETIME_DATETIME_REPLACE_METHODDEF    \
+    {"replace", _PyCFunction_CAST(datetime_datetime_replace), METH_FASTCALL|METH_KEYWORDS, datetime_datetime_replace__doc__},
+
+static PyObject *
+datetime_datetime_replace_impl(PyDateTime_DateTime *self, int year,
+                               int month, int day, int hour, int minute,
+                               int second, int microsecond, PyObject *tzinfo,
+                               int fold);
+
+static PyObject *
+datetime_datetime_replace(PyDateTime_DateTime *self, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
+{
+    PyObject *return_value = NULL;
+    #if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE)
+
+    #define NUM_KEYWORDS 9
+    static struct {
+        PyGC_Head _this_is_not_used;
+        PyObject_VAR_HEAD
+        PyObject *ob_item[NUM_KEYWORDS];
+    } _kwtuple = {
+        .ob_base = PyVarObject_HEAD_INIT(&PyTuple_Type, NUM_KEYWORDS)
+        .ob_item = { &_Py_ID(year), &_Py_ID(month), &_Py_ID(day), &_Py_ID(hour), &_Py_ID(minute), &_Py_ID(second), &_Py_ID(microsecond), &_Py_ID(tzinfo), &_Py_ID(fold), },
+    };
+    #undef NUM_KEYWORDS
+    #define KWTUPLE (&_kwtuple.ob_base.ob_base)
+
+    #else  // !Py_BUILD_CORE
+    #  define KWTUPLE NULL
+    #endif  // !Py_BUILD_CORE
+
+    static const char * const _keywords[] = {"year", "month", "day", "hour", "minute", "second", "microsecond", "tzinfo", "fold", NULL};
+    static _PyArg_Parser _parser = {
+        .keywords = _keywords,
+        .fname = "replace",
+        .kwtuple = KWTUPLE,
+    };
+    #undef KWTUPLE
+    PyObject *argsbuf[9];
+    Py_ssize_t noptargs = nargs + (kwnames ? PyTuple_GET_SIZE(kwnames) : 0) - 0;
+    int year = GET_YEAR(self);
+    int month = GET_MONTH(self);
+    int day = GET_DAY(self);
+    int hour = DATE_GET_HOUR(self);
+    int minute = DATE_GET_MINUTE(self);
+    int second = DATE_GET_SECOND(self);
+    int microsecond = DATE_GET_MICROSECOND(self);
+    PyObject *tzinfo = HASTZINFO(self) ? self->tzinfo : Py_None;
+    int fold = DATE_GET_FOLD(self);
+
+    args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 0, 8, 0, argsbuf);
+    if (!args) {
+        goto exit;
+    }
+    if (!noptargs) {
+        goto skip_optional_pos;
+    }
+    if (args[0]) {
+        year = PyLong_AsInt(args[0]);
+        if (year == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[1]) {
+        month = PyLong_AsInt(args[1]);
+        if (month == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[2]) {
+        day = PyLong_AsInt(args[2]);
+        if (day == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[3]) {
+        hour = PyLong_AsInt(args[3]);
+        if (hour == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[4]) {
+        minute = PyLong_AsInt(args[4]);
+        if (minute == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[5]) {
+        second = PyLong_AsInt(args[5]);
+        if (second == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[6]) {
+        microsecond = PyLong_AsInt(args[6]);
+        if (microsecond == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (args[7]) {
+        tzinfo = args[7];
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+skip_optional_pos:
+    if (!noptargs) {
+        goto skip_optional_kwonly;
+    }
+    fold = PyLong_AsInt(args[8]);
+    if (fold == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional_kwonly:
+    return_value = datetime_datetime_replace_impl(self, year, month, day, hour, minute, second, microsecond, tzinfo, fold);
+
+exit:
+    return return_value;
+}
+/*[clinic end generated code: output=c7a04b865b1e0890 input=a9049054013a1b77]*/