PERL_CALLCONV U8* Perl_utf8_to_bytes(pTHX_ U8 *s, STRLEN *len);
PERL_CALLCONV U8* Perl_bytes_from_utf8(pTHX_ U8 *s, STRLEN *len, bool *is_utf8);
PERL_CALLCONV U8* Perl_bytes_to_utf8(pTHX_ U8 *s, STRLEN *len);
-PERL_CALLCONV UV Perl_utf8_to_uv_simple(pTHX_ U8 *s, STRLEN* retlen);
-PERL_CALLCONV UV Perl_utf8_to_uv(pTHX_ U8 *s, STRLEN curlen, STRLEN* retlen, U32 flags);
-PERL_CALLCONV U8* Perl_uv_to_utf8(pTHX_ U8 *d, UV uv);
+PERL_CALLCONV UV Perl_utf8_to_uvchr(pTHX_ U8 *s, STRLEN* retlen);
+PERL_CALLCONV UV Perl_utf8_to_uvuni(pTHX_ U8 *s, STRLEN* retlen);
+PERL_CALLCONV UV Perl_utf8n_to_uvchr(pTHX_ U8 *s, STRLEN curlen, STRLEN* retlen, U32 flags);
+PERL_CALLCONV UV Perl_utf8n_to_uvuni(pTHX_ U8 *s, STRLEN curlen, STRLEN* retlen, U32 flags);
+PERL_CALLCONV U8* Perl_uvchr_to_utf8(pTHX_ U8 *d, UV uv);
+PERL_CALLCONV U8* Perl_uvuni_to_utf8(pTHX_ U8 *d, UV uv);
PERL_CALLCONV void Perl_vivify_defelem(pTHX_ SV* sv);
PERL_CALLCONV void Perl_vivify_ref(pTHX_ SV* sv, U32 to_what);
PERL_CALLCONV I32 Perl_wait4pid(pTHX_ Pid_t pid, int* statusp, int flags);
PERL_CALLCONV char* Perl_sv_pv(pTHX_ SV *sv);
PERL_CALLCONV char* Perl_sv_pvutf8(pTHX_ SV *sv);
PERL_CALLCONV char* Perl_sv_pvbyte(pTHX_ SV *sv);
-PERL_CALLCONV void Perl_sv_utf8_upgrade(pTHX_ SV *sv);
+PERL_CALLCONV STRLEN Perl_sv_utf8_upgrade(pTHX_ SV *sv);
PERL_CALLCONV bool Perl_sv_utf8_downgrade(pTHX_ SV *sv, bool fail_ok);
PERL_CALLCONV void Perl_sv_utf8_encode(pTHX_ SV *sv);
PERL_CALLCONV bool Perl_sv_utf8_decode(pTHX_ SV *sv);