Issue #14738: Speed-up UTF-8 decoding on non-ASCII data.  Patch by Serhiy Storchaka.
diff --git a/Objects/stringlib/asciilib.h b/Objects/stringlib/asciilib.h
index fa481c0..ab5bae7 100644
--- a/Objects/stringlib/asciilib.h
+++ b/Objects/stringlib/asciilib.h
@@ -7,6 +7,7 @@
 #define STRINGLIB(F)             asciilib_##F
 #define STRINGLIB_OBJECT         PyUnicodeObject
 #define STRINGLIB_SIZEOF_CHAR    1
+#define STRINGLIB_MAX_CHAR       0x7Fu
 #define STRINGLIB_CHAR           Py_UCS1
 #define STRINGLIB_TYPE_NAME      "unicode"
 #define STRINGLIB_PARSE_CODE     "U"