py/objstr: Optimise mp_obj_new_str_from_vstr for known-safe strings.

The new `mp_obj_new_str_from_utf8_vstr` can be used when you know you
already have a unicode-safe string.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/py/obj.h b/py/obj.h
index d171e0fe6..0b0a9692e 100644
--- a/py/obj.h
+++ b/py/obj.h
@@ -792,6 +792,11 @@ mp_obj_t mp_obj_new_int_from_ull(unsigned long long val); // this must return a
 mp_obj_t mp_obj_new_str(const char *data, size_t len);
 mp_obj_t mp_obj_new_str_via_qstr(const char *data, size_t len);
 mp_obj_t mp_obj_new_str_from_vstr(vstr_t *vstr);
+#if MICROPY_PY_BUILTINS_STR_UNICODE && MICROPY_PY_BUILTINS_STR_UNICODE_CHECK
+mp_obj_t mp_obj_new_str_from_utf8_vstr(vstr_t *vstr); // only use when vstr is already known to be utf-8 encoded
+#else
+#define mp_obj_new_str_from_utf8_vstr mp_obj_new_str_from_vstr
+#endif
 mp_obj_t mp_obj_new_bytes_from_vstr(vstr_t *vstr);
 mp_obj_t mp_obj_new_bytes(const byte *data, size_t len);
 mp_obj_t mp_obj_new_bytearray(size_t n, const void *items);