bpo-46881: Statically allocate and initialize the latin1 characters. (GH-31616)

6 files changed, 317 insertions, 66 deletions

diff --git a/Include/internal/pycore_global_strings.h b/Include/internal/pycore_global_strings.h
index 74ebc14..755d69a 100644
--- a/Include/internal/pycore_global_strings.h
+++ b/Include/internal/pycore_global_strings.h
@@ -350,6 +350,14 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(write)
         STRUCT_FOR_ID(zipimporter)
     } identifiers;
+    struct {
+        PyASCIIObject _ascii;
+        uint8_t _data[2];
+    } ascii[128];
+    struct {
+        PyCompactUnicodeObject _latin1;
+        uint8_t _data[2];
+    } latin1[128];
 };
 /* End auto-generated code */
 
diff --git a/Include/internal/pycore_runtime_init.h b/Include/internal/pycore_runtime_init.h
index 8b1abcd..5ba1826 100644
--- a/Include/internal/pycore_runtime_init.h
+++ b/Include/internal/pycore_runtime_init.h
@@ -93,26 +93,34 @@ extern "C" {
         _PyBytes_SIMPLE_INIT(CH, 1) \
     }
 
-#define _PyASCIIObject_INIT(LITERAL) \
+#define _PyUnicode_ASCII_BASE_INIT(LITERAL, ASCII) \
     { \
-        ._ascii = { \
-            .ob_base = _PyObject_IMMORTAL_INIT(&PyUnicode_Type), \
-            .length = sizeof(LITERAL) - 1, \
-            .hash = -1, \
-            .state = { \
-                .kind = 1, \
-                .compact = 1, \
-                .ascii = 1, \
-                .ready = 1, \
-            }, \
+        .ob_base = _PyObject_IMMORTAL_INIT(&PyUnicode_Type), \
+        .length = sizeof(LITERAL) - 1, \
+        .hash = -1, \
+        .state = { \
+            .kind = 1, \
+            .compact = 1, \
+            .ascii = ASCII, \
+            .ready = 1, \
         }, \
-        ._data = LITERAL, \
+    }
+#define _PyASCIIObject_INIT(LITERAL) \
+    { \
+        ._ascii = _PyUnicode_ASCII_BASE_INIT(LITERAL, 1), \
+        ._data = LITERAL \
     }
 #define INIT_STR(NAME, LITERAL) \
     ._ ## NAME = _PyASCIIObject_INIT(LITERAL)
 #define INIT_ID(NAME) \
     ._ ## NAME = _PyASCIIObject_INIT(#NAME)
-
+#define _PyUnicode_LATIN1_INIT(LITERAL) \
+    { \
+        ._latin1 = { \
+            ._base = _PyUnicode_ASCII_BASE_INIT(LITERAL, 0), \
+        }, \
+        ._data = LITERAL, \
+    }
 
 /* The following is auto-generated by Tools/scripts/generate_global_objects.py. */
 #define _Py_global_objects_INIT { \
@@ -965,6 +973,266 @@ extern "C" {
                 INIT_ID(write), \
                 INIT_ID(zipimporter), \
             }, \
+            .ascii = { \
+                _PyASCIIObject_INIT("\x00"), \
+                _PyASCIIObject_INIT("\x01"), \
+                _PyASCIIObject_INIT("\x02"), \
+                _PyASCIIObject_INIT("\x03"), \
+                _PyASCIIObject_INIT("\x04"), \
+                _PyASCIIObject_INIT("\x05"), \
+                _PyASCIIObject_INIT("\x06"), \
+                _PyASCIIObject_INIT("\x07"), \
+                _PyASCIIObject_INIT("\x08"), \
+                _PyASCIIObject_INIT("\x09"), \
+                _PyASCIIObject_INIT("\x0a"), \
+                _PyASCIIObject_INIT("\x0b"), \
+                _PyASCIIObject_INIT("\x0c"), \
+                _PyASCIIObject_INIT("\x0d"), \
+                _PyASCIIObject_INIT("\x0e"), \
+                _PyASCIIObject_INIT("\x0f"), \
+                _PyASCIIObject_INIT("\x10"), \
+                _PyASCIIObject_INIT("\x11"), \
+                _PyASCIIObject_INIT("\x12"), \
+                _PyASCIIObject_INIT("\x13"), \
+                _PyASCIIObject_INIT("\x14"), \
+                _PyASCIIObject_INIT("\x15"), \
+                _PyASCIIObject_INIT("\x16"), \
+                _PyASCIIObject_INIT("\x17"), \
+                _PyASCIIObject_INIT("\x18"), \
+                _PyASCIIObject_INIT("\x19"), \
+                _PyASCIIObject_INIT("\x1a"), \
+                _PyASCIIObject_INIT("\x1b"), \
+                _PyASCIIObject_INIT("\x1c"), \
+                _PyASCIIObject_INIT("\x1d"), \
+                _PyASCIIObject_INIT("\x1e"), \
+                _PyASCIIObject_INIT("\x1f"), \
+                _PyASCIIObject_INIT("\x20"), \
+                _PyASCIIObject_INIT("\x21"), \
+                _PyASCIIObject_INIT("\x22"), \
+                _PyASCIIObject_INIT("\x23"), \
+                _PyASCIIObject_INIT("\x24"), \
+                _PyASCIIObject_INIT("\x25"), \
+                _PyASCIIObject_INIT("\x26"), \
+                _PyASCIIObject_INIT("\x27"), \
+                _PyASCIIObject_INIT("\x28"), \
+                _PyASCIIObject_INIT("\x29"), \
+                _PyASCIIObject_INIT("\x2a"), \
+                _PyASCIIObject_INIT("\x2b"), \
+                _PyASCIIObject_INIT("\x2c"), \
+                _PyASCIIObject_INIT("\x2d"), \
+                _PyASCIIObject_INIT("\x2e"), \
+                _PyASCIIObject_INIT("\x2f"), \
+                _PyASCIIObject_INIT("\x30"), \
+                _PyASCIIObject_INIT("\x31"), \
+                _PyASCIIObject_INIT("\x32"), \
+                _PyASCIIObject_INIT("\x33"), \
+                _PyASCIIObject_INIT("\x34"), \
+                _PyASCIIObject_INIT("\x35"), \
+                _PyASCIIObject_INIT("\x36"), \
+                _PyASCIIObject_INIT("\x37"), \
+                _PyASCIIObject_INIT("\x38"), \
+                _PyASCIIObject_INIT("\x39"), \
+                _PyASCIIObject_INIT("\x3a"), \
+                _PyASCIIObject_INIT("\x3b"), \
+                _PyASCIIObject_INIT("\x3c"), \
+                _PyASCIIObject_INIT("\x3d"), \
+                _PyASCIIObject_INIT("\x3e"), \
+                _PyASCIIObject_INIT("\x3f"), \
+                _PyASCIIObject_INIT("\x40"), \
+                _PyASCIIObject_INIT("\x41"), \
+                _PyASCIIObject_INIT("\x42"), \
+                _PyASCIIObject_INIT("\x43"), \
+                _PyASCIIObject_INIT("\x44"), \
+                _PyASCIIObject_INIT("\x45"), \
+                _PyASCIIObject_INIT("\x46"), \
+                _PyASCIIObject_INIT("\x47"), \
+                _PyASCIIObject_INIT("\x48"), \
+                _PyASCIIObject_INIT("\x49"), \
+                _PyASCIIObject_INIT("\x4a"), \
+                _PyASCIIObject_INIT("\x4b"), \
+                _PyASCIIObject_INIT("\x4c"), \
+                _PyASCIIObject_INIT("\x4d"), \
+                _PyASCIIObject_INIT("\x4e"), \
+                _PyASCIIObject_INIT("\x4f"), \
+                _PyASCIIObject_INIT("\x50"), \
+                _PyASCIIObject_INIT("\x51"), \
+                _PyASCIIObject_INIT("\x52"), \
+                _PyASCIIObject_INIT("\x53"), \
+                _PyASCIIObject_INIT("\x54"), \
+                _PyASCIIObject_INIT("\x55"), \
+                _PyASCIIObject_INIT("\x56"), \
+                _PyASCIIObject_INIT("\x57"), \
+                _PyASCIIObject_INIT("\x58"), \
+                _PyASCIIObject_INIT("\x59"), \
+                _PyASCIIObject_INIT("\x5a"), \
+                _PyASCIIObject_INIT("\x5b"), \
+                _PyASCIIObject_INIT("\x5c"), \
+                _PyASCIIObject_INIT("\x5d"), \
+                _PyASCIIObject_INIT("\x5e"), \
+                _PyASCIIObject_INIT("\x5f"), \
+                _PyASCIIObject_INIT("\x60"), \
+                _PyASCIIObject_INIT("\x61"), \
+                _PyASCIIObject_INIT("\x62"), \
+                _PyASCIIObject_INIT("\x63"), \
+                _PyASCIIObject_INIT("\x64"), \
+                _PyASCIIObject_INIT("\x65"), \
+                _PyASCIIObject_INIT("\x66"), \
+                _PyASCIIObject_INIT("\x67"), \
+                _PyASCIIObject_INIT("\x68"), \
+                _PyASCIIObject_INIT("\x69"), \
+                _PyASCIIObject_INIT("\x6a"), \
+                _PyASCIIObject_INIT("\x6b"), \
+                _PyASCIIObject_INIT("\x6c"), \
+                _PyASCIIObject_INIT("\x6d"), \
+                _PyASCIIObject_INIT("\x6e"), \
+                _PyASCIIObject_INIT("\x6f"), \
+                _PyASCIIObject_INIT("\x70"), \
+                _PyASCIIObject_INIT("\x71"), \
+                _PyASCIIObject_INIT("\x72"), \
+                _PyASCIIObject_INIT("\x73"), \
+                _PyASCIIObject_INIT("\x74"), \
+                _PyASCIIObject_INIT("\x75"), \
+                _PyASCIIObject_INIT("\x76"), \
+                _PyASCIIObject_INIT("\x77"), \
+                _PyASCIIObject_INIT("\x78"), \
+                _PyASCIIObject_INIT("\x79"), \
+                _PyASCIIObject_INIT("\x7a"), \
+                _PyASCIIObject_INIT("\x7b"), \
+                _PyASCIIObject_INIT("\x7c"), \
+                _PyASCIIObject_INIT("\x7d"), \
+                _PyASCIIObject_INIT("\x7e"), \
+                _PyASCIIObject_INIT("\x7f"), \
+            }, \
+            .latin1 = { \
+                _PyUnicode_LATIN1_INIT("\x80"), \
+                _PyUnicode_LATIN1_INIT("\x81"), \
+                _PyUnicode_LATIN1_INIT("\x82"), \
+                _PyUnicode_LATIN1_INIT("\x83"), \
+                _PyUnicode_LATIN1_INIT("\x84"), \
+                _PyUnicode_LATIN1_INIT("\x85"), \
+                _PyUnicode_LATIN1_INIT("\x86"), \
+                _PyUnicode_LATIN1_INIT("\x87"), \
+                _PyUnicode_LATIN1_INIT("\x88"), \
+                _PyUnicode_LATIN1_INIT("\x89"), \
+                _PyUnicode_LATIN1_INIT("\x8a"), \
+                _PyUnicode_LATIN1_INIT("\x8b"), \
+                _PyUnicode_LATIN1_INIT("\x8c"), \
+                _PyUnicode_LATIN1_INIT("\x8d"), \
+                _PyUnicode_LATIN1_INIT("\x8e"), \
+                _PyUnicode_LATIN1_INIT("\x8f"), \
+                _PyUnicode_LATIN1_INIT("\x90"), \
+                _PyUnicode_LATIN1_INIT("\x91"), \
+                _PyUnicode_LATIN1_INIT("\x92"), \
+                _PyUnicode_LATIN1_INIT("\x93"), \
+                _PyUnicode_LATIN1_INIT("\x94"), \
+                _PyUnicode_LATIN1_INIT("\x95"), \
+                _PyUnicode_LATIN1_INIT("\x96"), \
+                _PyUnicode_LATIN1_INIT("\x97"), \
+                _PyUnicode_LATIN1_INIT("\x98"), \
+                _PyUnicode_LATIN1_INIT("\x99"), \
+                _PyUnicode_LATIN1_INIT("\x9a"), \
+                _PyUnicode_LATIN1_INIT("\x9b"), \
+                _PyUnicode_LATIN1_INIT("\x9c"), \
+                _PyUnicode_LATIN1_INIT("\x9d"), \
+                _PyUnicode_LATIN1_INIT("\x9e"), \
+                _PyUnicode_LATIN1_INIT("\x9f"), \
+                _PyUnicode_LATIN1_INIT("\xa0"), \
+                _PyUnicode_LATIN1_INIT("\xa1"), \
+                _PyUnicode_LATIN1_INIT("\xa2"), \
+                _PyUnicode_LATIN1_INIT("\xa3"), \
+                _PyUnicode_LATIN1_INIT("\xa4"), \
+                _PyUnicode_LATIN1_INIT("\xa5"), \
+                _PyUnicode_LATIN1_INIT("\xa6"), \
+                _PyUnicode_LATIN1_INIT("\xa7"), \
+                _PyUnicode_LATIN1_INIT("\xa8"), \
+                _PyUnicode_LATIN1_INIT("\xa9"), \
+                _PyUnicode_LATIN1_INIT("\xaa"), \
+                _PyUnicode_LATIN1_INIT("\xab"), \
+                _PyUnicode_LATIN1_INIT("\xac"), \
+                _PyUnicode_LATIN1_INIT("\xad"), \
+                _PyUnicode_LATIN1_INIT("\xae"), \
+                _PyUnicode_LATIN1_INIT("\xaf"), \
+                _PyUnicode_LATIN1_INIT("\xb0"), \
+                _PyUnicode_LATIN1_INIT("\xb1"), \
+                _PyUnicode_LATIN1_INIT("\xb2"), \
+                _PyUnicode_LATIN1_INIT("\xb3"), \
+                _PyUnicode_LATIN1_INIT("\xb4"), \
+                _PyUnicode_LATIN1_INIT("\xb5"), \
+                _PyUnicode_LATIN1_INIT("\xb6"), \
+                _PyUnicode_LATIN1_INIT("\xb7"), \
+                _PyUnicode_LATIN1_INIT("\xb8"), \
+                _PyUnicode_LATIN1_INIT("\xb9"), \
+                _PyUnicode_LATIN1_INIT("\xba"), \
+                _PyUnicode_LATIN1_INIT("\xbb"), \
+                _PyUnicode_LATIN1_INIT("\xbc"), \
+                _PyUnicode_LATIN1_INIT("\xbd"), \
+                _PyUnicode_LATIN1_INIT("\xbe"), \
+                _PyUnicode_LATIN1_INIT("\xbf"), \
+                _PyUnicode_LATIN1_INIT("\xc0"), \
+                _PyUnicode_LATIN1_INIT("\xc1"), \
+                _PyUnicode_LATIN1_INIT("\xc2"), \
+                _PyUnicode_LATIN1_INIT("\xc3"), \
+                _PyUnicode_LATIN1_INIT("\xc4"), \
+                _PyUnicode_LATIN1_INIT("\xc5"), \
+                _PyUnicode_LATIN1_INIT("\xc6"), \
+                _PyUnicode_LATIN1_INIT("\xc7"), \
+                _PyUnicode_LATIN1_INIT("\xc8"), \
+                _PyUnicode_LATIN1_INIT("\xc9"), \
+                _PyUnicode_LATIN1_INIT("\xca"), \
+                _PyUnicode_LATIN1_INIT("\xcb"), \
+                _PyUnicode_LATIN1_INIT("\xcc"), \
+                _PyUnicode_LATIN1_INIT("\xcd"), \
+                _PyUnicode_LATIN1_INIT("\xce"), \
+                _PyUnicode_LATIN1_INIT("\xcf"), \
+                _PyUnicode_LATIN1_INIT("\xd0"), \
+                _PyUnicode_LATIN1_INIT("\xd1"), \
+                _PyUnicode_LATIN1_INIT("\xd2"), \
+                _PyUnicode_LATIN1_INIT("\xd3"), \
+                _PyUnicode_LATIN1_INIT("\xd4"), \
+                _PyUnicode_LATIN1_INIT("\xd5"), \
+                _PyUnicode_LATIN1_INIT("\xd6"), \
+                _PyUnicode_LATIN1_INIT("\xd7"), \
+                _PyUnicode_LATIN1_INIT("\xd8"), \
+                _PyUnicode_LATIN1_INIT("\xd9"), \
+                _PyUnicode_LATIN1_INIT("\xda"), \
+                _PyUnicode_LATIN1_INIT("\xdb"), \
+                _PyUnicode_LATIN1_INIT("\xdc"), \
+                _PyUnicode_LATIN1_INIT("\xdd"), \
+                _PyUnicode_LATIN1_INIT("\xde"), \
+                _PyUnicode_LATIN1_INIT("\xdf"), \
+                _PyUnicode_LATIN1_INIT("\xe0"), \
+                _PyUnicode_LATIN1_INIT("\xe1"), \
+                _PyUnicode_LATIN1_INIT("\xe2"), \
+                _PyUnicode_LATIN1_INIT("\xe3"), \
+                _PyUnicode_LATIN1_INIT("\xe4"), \
+                _PyUnicode_LATIN1_INIT("\xe5"), \
+                _PyUnicode_LATIN1_INIT("\xe6"), \
+                _PyUnicode_LATIN1_INIT("\xe7"), \
+                _PyUnicode_LATIN1_INIT("\xe8"), \
+                _PyUnicode_LATIN1_INIT("\xe9"), \
+                _PyUnicode_LATIN1_INIT("\xea"), \
+                _PyUnicode_LATIN1_INIT("\xeb"), \
+                _PyUnicode_LATIN1_INIT("\xec"), \
+                _PyUnicode_LATIN1_INIT("\xed"), \
+                _PyUnicode_LATIN1_INIT("\xee"), \
+                _PyUnicode_LATIN1_INIT("\xef"), \
+                _PyUnicode_LATIN1_INIT("\xf0"), \
+                _PyUnicode_LATIN1_INIT("\xf1"), \
+                _PyUnicode_LATIN1_INIT("\xf2"), \
+                _PyUnicode_LATIN1_INIT("\xf3"), \
+                _PyUnicode_LATIN1_INIT("\xf4"), \
+                _PyUnicode_LATIN1_INIT("\xf5"), \
+                _PyUnicode_LATIN1_INIT("\xf6"), \
+                _PyUnicode_LATIN1_INIT("\xf7"), \
+                _PyUnicode_LATIN1_INIT("\xf8"), \
+                _PyUnicode_LATIN1_INIT("\xf9"), \
+                _PyUnicode_LATIN1_INIT("\xfa"), \
+                _PyUnicode_LATIN1_INIT("\xfb"), \
+                _PyUnicode_LATIN1_INIT("\xfc"), \
+                _PyUnicode_LATIN1_INIT("\xfd"), \
+                _PyUnicode_LATIN1_INIT("\xfe"), \
+                _PyUnicode_LATIN1_INIT("\xff"), \
+            }, \
         }, \
         \
         .tuple_empty = { \
diff --git a/Include/internal/pycore_unicodeobject.h b/Include/internal/pycore_unicodeobject.h
index 977bbeb..4394ce9 100644
--- a/Include/internal/pycore_unicodeobject.h
+++ b/Include/internal/pycore_unicodeobject.h
@@ -44,9 +44,6 @@ struct _Py_unicode_ids {
 };
 
 struct _Py_unicode_state {
-    /* Single character Unicode strings in the Latin-1 range are being
-       shared as well. */
-    PyObject *latin1[256];
     struct _Py_unicode_fs_codec fs_codec;
 
     // Unicode identifiers (_Py_Identifier): see _PyUnicode_FromId()
diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-03-03-09-08-17.bpo-46881.ckD4tT.rst b/Misc/NEWS.d/next/Core and Builtins/2022-03-03-09-08-17.bpo-46881.ckD4tT.rst
new file mode 100644
index 0000000..88434dd
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2022-03-03-09-08-17.bpo-46881.ckD4tT.rst
@@ -0,0 +1 @@
+Statically allocate and initialize the latin1 characters.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 908ad51..9052c53 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -206,6 +206,11 @@ extern "C" {
             *_to++ = (to_type) *_iter++;                \
     } while (0)
 
+#define LATIN1(ch)  \
+    (ch < 128 \
+     ? (PyObject*)&_Py_SINGLETON(strings).ascii[ch] \
+     : (PyObject*)&_Py_SINGLETON(strings).latin1[ch - 128])
+
 #ifdef MS_WINDOWS
    /* On Windows, overallocate by 50% is the best factor */
 #  define OVERALLOCATE_FACTOR 2
@@ -249,14 +254,6 @@ static int unicode_is_singleton(PyObject *unicode);
 #endif
 
 
-static struct _Py_unicode_state*
-get_unicode_state(void)
-{
-    PyInterpreterState *interp = _PyInterpreterState_GET();
-    return &interp->unicode;
-}
-
-
 // Return a borrowed reference to the empty string singleton.
 static inline PyObject* unicode_get_empty(void)
 {
@@ -680,24 +677,10 @@ unicode_result_ready(PyObject *unicode)
         if (kind == PyUnicode_1BYTE_KIND) {
             const Py_UCS1 *data = PyUnicode_1BYTE_DATA(unicode);
             Py_UCS1 ch = data[0];
-            struct _Py_unicode_state *state = get_unicode_state();
-            PyObject *latin1_char = state->latin1[ch];
-            if (latin1_char != NULL) {
-                if (unicode != latin1_char) {
-                    Py_INCREF(latin1_char);
-                    Py_DECREF(unicode);
-                }
-                return latin1_char;
+            if (unicode != LATIN1(ch)) {
+                Py_DECREF(unicode);
             }
-            else {
-                assert(_PyUnicode_CheckConsistency(unicode, 1));
-                Py_INCREF(unicode);
-                state->latin1[ch] = unicode;
-                return unicode;
-            }
-        }
-        else {
-            assert(PyUnicode_READ_CHAR(unicode, 0) >= 256);
+            return get_latin1_char(ch);
         }
     }
 
@@ -1990,11 +1973,10 @@ unicode_is_singleton(PyObject *unicode)
         return 1;
     }
 
-    struct _Py_unicode_state *state = get_unicode_state();
     PyASCIIObject *ascii = (PyASCIIObject *)unicode;
     if (ascii->state.kind != PyUnicode_WCHAR_KIND && ascii->length == 1) {
         Py_UCS4 ch = PyUnicode_READ_CHAR(unicode, 0);
-        if (ch < 256 && state->latin1[ch] == unicode) {
+        if (ch < 256 && LATIN1(ch) == unicode) {
             return 1;
         }
     }
@@ -2137,25 +2119,7 @@ unicode_write_cstr(PyObject *unicode, Py_ssize_t index,
 static PyObject*
 get_latin1_char(Py_UCS1 ch)
 {
-    struct _Py_unicode_state *state = get_unicode_state();
-
-    PyObject *unicode = state->latin1[ch];
-    if (unicode) {
-        Py_INCREF(unicode);
-        return unicode;
-    }
-
-    unicode = PyUnicode_New(1, ch);
-    if (!unicode) {
-        return NULL;
-    }
-
-    PyUnicode_1BYTE_DATA(unicode)[0] = ch;
-    assert(_PyUnicode_CheckConsistency(unicode, 1));
-
-    Py_INCREF(unicode);
-    state->latin1[ch] = unicode;
-    return unicode;
+    return Py_NewRef(LATIN1(ch));
 }
 
 static PyObject*
@@ -15535,6 +15499,10 @@ _PyUnicode_InitGlobalObjects(PyInterpreterState *interp)
 
 #ifdef Py_DEBUG
     assert(_PyUnicode_CheckConsistency(&_Py_STR(empty), 1));
+
+    for (int i = 0; i < 256; i++) {
+        assert(_PyUnicode_CheckConsistency(LATIN1(i), 1));
+    }
 #endif
 
     return _PyStatus_OK();
@@ -16113,10 +16081,6 @@ _PyUnicode_Fini(PyInterpreterState *interp)
     _PyUnicode_FiniEncodings(&state->fs_codec);
 
     unicode_clear_identifiers(state);
-
-    for (Py_ssize_t i = 0; i < 256; i++) {
-        Py_CLEAR(state->latin1[i]);
-    }
 }
 
 
diff --git a/Tools/scripts/generate_global_objects.py b/Tools/scripts/generate_global_objects.py
index 867358c..17ddb8b 100644
--- a/Tools/scripts/generate_global_objects.py
+++ b/Tools/scripts/generate_global_objects.py
@@ -196,6 +196,13 @@ def generate_global_strings(identifiers, strings):
                 for name in sorted(identifiers):
                     assert name.isidentifier(), name
                     printer.write(f'STRUCT_FOR_ID({name})')
+            with printer.block('struct', ' ascii[128];'):
+                printer.write("PyASCIIObject _ascii;")
+                printer.write("uint8_t _data[2];")
+            with printer.block('struct', ' latin1[128];'):
+                printer.write("PyCompactUnicodeObject _latin1;")
+                printer.write("uint8_t _data[2];")
+
         printer.write(END)
         printer.write(after)
 
@@ -252,6 +259,12 @@ def generate_runtime_init(identifiers, strings):
                         for name in sorted(identifiers):
                             assert name.isidentifier(), name
                             printer.write(f'INIT_ID({name}),')
+                    with printer.block('.ascii =', ','):
+                        for i in range(128):
+                            printer.write(f'_PyASCIIObject_INIT("\\x{i:02x}"),')
+                    with printer.block('.latin1 =', ','):
+                        for i in range(128, 256):
+                            printer.write(f'_PyUnicode_LATIN1_INIT("\\x{i:02x}"),')
                 printer.write('')
                 with printer.block('.tuple_empty =', ','):
                     printer.write('.ob_base = _PyVarObject_IMMORTAL_INIT(&PyTuple_Type, 0)')