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subkernel: separate tags and data

This commit is contained in:
mwojcik 2023-10-17 17:46:56 +08:00 committed by Sébastien Bourdeauducq
parent 6705c9fbfb
commit b168f0bb4b
11 changed files with 134 additions and 88 deletions
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17
artiq/compiler/ir.py
View File

@ -764,6 +764,23 @@ class GetOptArgFromRemote(GetArgFromRemote):
def opcode(self):
return "getoptargfromremote({})".format(repr(self.arg_name))
class SubkernelAwaitArgs(Instruction):
"""
A builtin instruction that takes min and max received messages as operands,
and a list of received types.
:ivar arg_types: (list of types) types of passed arguments (including optional)
"""
"""
:param arg_types: (list of types) types of passed arguments (including optional)
"""
def __init__(self, operands, arg_types, name=None):
assert isinstance(arg_types, list)
self.arg_types = arg_types
super().__init__(operands, builtins.TNone(), name)
class GetAttr(Instruction):
"""
An intruction that loads an attribute from an object,

3
artiq/compiler/transforms/artiq_ir_generator.py
View File

@ -2614,8 +2614,9 @@ class ARTIQIRGenerator(algorithm.Visitor):
min_args = ir.Constant(len(fn_typ.args)-offset, builtins.TInt8())
max_args = ir.Constant(fn_typ.arity()-offset, builtins.TInt8())
rcvd_count = self.append(ir.Builtin("subkernel_await_args", [min_args, max_args], builtins.TNone()))
arg_types = list(fn_typ.args.items())[offset:]
arg_type_list = [a[1] for a in arg_types] + [a[1] for a in fn_typ.optargs.items()]
rcvd_count = self.append(ir.SubkernelAwaitArgs([min_args, max_args], arg_type_list))
# obligatory arguments
for arg_name, arg_type in arg_types:
args[index] = self.append(ir.GetArgFromRemote(arg_name, arg_type,

38
artiq/compiler/transforms/llvm_ir_generator.py
View File

@ -405,7 +405,7 @@ class LLVMIRGenerator:
elif name == "subkernel_await_finish":
llty = ll.FunctionType(llvoid, [lli32, lli64])
elif name == "subkernel_await_message":
llty = ll.FunctionType(lli8, [lli32, lli64, lli8, lli8])
llty = ll.FunctionType(lli8, [lli32, lli64, llsliceptr, lli8, lli8])
# with now-pinning
elif name == "now":
@ -1400,12 +1400,6 @@ class LLVMIRGenerator:
return self.llbuilder.call(self.llbuiltin("delay_mu"), [llinterval])
elif insn.op == "end_catch":
return self.llbuilder.call(self.llbuiltin("__artiq_end_catch"), [])
elif insn.op == "subkernel_await_args":
llmin = self.map(insn.operands[0])
llmax = self.map(insn.operands[1])
return self.llbuilder.call(self.llbuiltin("subkernel_await_message"),
[ll.Constant(lli32, 0), ll.Constant(lli64, 10_000), llmin, llmax],
name="subkernel.await.args")
elif insn.op == "subkernel_await_finish":
llsid = self.map(insn.operands[0])
lltimeout = self.map(insn.operands[1])
@ -1414,7 +1408,9 @@ class LLVMIRGenerator:
elif insn.op == "subkernel_retrieve_return":
llsid = self.map(insn.operands[0])
lltimeout = self.map(insn.operands[1])
self.llbuilder.call(self.llbuiltin("subkernel_await_message"), [llsid, lltimeout, ll.Constant(lli8, 1), ll.Constant(lli8, 1)],
lltagptr = self._build_subkernel_tags([insn.type])
self.llbuilder.call(self.llbuiltin("subkernel_await_message"),
[llsid, lltimeout, lltagptr, ll.Constant(lli8, 1), ll.Constant(lli8, 1)],
name="subkernel.await.message")
llstackptr = self.llbuilder.call(self.llbuiltin("llvm.stacksave"), [],
name="subkernel.arg.stack")
@ -1426,6 +1422,14 @@ class LLVMIRGenerator:
else:
assert False
def process_SubkernelAwaitArgs(self, insn):
llmin = self.map(insn.operands[0])
llmax = self.map(insn.operands[1])
lltagptr = self._build_subkernel_tags(insn.arg_types)
return self.llbuilder.call(self.llbuiltin("subkernel_await_message"),
[ll.Constant(lli32, 0), ll.Constant(lli64, 10_000), lltagptr, llmin, llmax],
name="subkernel.await.args")
def process_Closure(self, insn):
llenv = self.map(insn.environment())
llenv = self.llbuilder.bitcast(llenv, llptr)
@ -1505,6 +1509,24 @@ class LLVMIRGenerator:
return llfun, list(llargs), llarg_attrs, llcallstackptr
def _build_subkernel_tags(self, tag_list):
def ret_error_handler(typ):
printer = types.TypePrinter()
note = diagnostic.Diagnostic("note",
"value of type {type}",
{"type": printer.name(typ)},
fun_loc)
diag = diagnostic.Diagnostic("error",
"type {type} is not supported in subkernels",
{"type": printer.name(fun_type.ret)},
fun_loc, notes=[note])
self.engine.process(diag)
tag = b"".join([ir.rpc_tag(arg_type, ret_error_handler) for arg_type in tag_list])
lltag = self.llconst_of_const(ir.Constant(tag, builtins.TStr()))
lltagptr = self.llbuilder.alloca(lltag.type)
self.llbuilder.store(lltag, lltagptr)
return lltagptr
def _build_rpc_recv(self, ret, llstackptr, llnormalblock=None, llunwindblock=None):
# T result = {
# void *ret_ptr = alloca(sizeof(T));

6
artiq/firmware/ksupport/lib.rs
View File

@ -138,7 +138,7 @@ extern fn rpc_send_async(service: u32, tag: &CSlice<u8>, data: *const *const ())
rpc_queue::enqueue(|mut slice| {
let length = {
let mut writer = Cursor::new(&mut slice[4..]);
rpc_proto::send_args(&mut writer, service, tag.as_ref(), data)?;
rpc_proto::send_args(&mut writer, service, tag.as_ref(), data, true)?;
writer.position()
};
io::ProtoWrite::write_u32(&mut slice, length as u32)
@ -499,8 +499,8 @@ extern fn subkernel_send_message(id: u32, count: u8, tag: &CSlice<u8>, data: *co
}
#[unwind(allowed)]
extern fn subkernel_await_message(id: u32, timeout: u64, min: u8, max: u8) -> u8 {
send(&SubkernelMsgRecvRequest { id: id, timeout: timeout });
extern fn subkernel_await_message(id: u32, timeout: u64, tags: &CSlice<u8>, min: u8, max: u8) -> u8 {
send(&SubkernelMsgRecvRequest { id: id, timeout: timeout, tags: tags.as_ref() });
recv!(SubkernelMsgRecvReply { status, count } => {
match status {
SubkernelStatus::NoError => {

2
artiq/firmware/libproto_artiq/kernel_proto.rs
View File

@ -108,7 +108,7 @@ pub enum Message<'a> {
SubkernelAwaitFinishRequest { id: u32, timeout: u64 },
SubkernelAwaitFinishReply { status: SubkernelStatus },
SubkernelMsgSend { id: u32, count: u8, tag: &'a [u8], data: *const *const () },
SubkernelMsgRecvRequest { id: u32, timeout: u64 },
SubkernelMsgRecvRequest { id: u32, timeout: u64, tags: &'a [u8] },
SubkernelMsgRecvReply { status: SubkernelStatus, count: u8 },
Log(fmt::Arguments<'a>),

41
artiq/firmware/libproto_artiq/rpc_proto.rs
View File

@ -190,9 +190,9 @@ unsafe fn recv_value<R, E>(reader: &mut R, tag: Tag, data: &mut *mut (),
}
}
pub fn recv_return<R, E>(reader: &mut R, tag_bytes: &[u8], data: *mut (),
pub fn recv_return<'a, R, E>(reader: &mut R, tag_bytes: &'a [u8], data: *mut (),
alloc: &dyn Fn(usize) -> Result<*mut (), E>)
-> Result<(), E>
-> Result<&'a [u8], E>
where R: Read + ?Sized,
E: From<Error<R::ReadError>>
{
@ -204,14 +204,16 @@ pub fn recv_return<R, E>(reader: &mut R, tag_bytes: &[u8], data: *mut (),
let mut data = data;
unsafe { recv_value(reader, tag, &mut data, alloc)? };
Ok(())
Ok(it.data)
}
unsafe fn send_elements<W>(writer: &mut W, elt_tag: Tag, length: usize, data: *const ())
unsafe fn send_elements<W>(writer: &mut W, elt_tag: Tag, length: usize, data: *const (), write_tags: bool)
-> Result<(), Error<W::WriteError>>
where W: Write + ?Sized
{
if write_tags {
writer.write_u8(elt_tag.as_u8())?;
}
match elt_tag {
// we cannot use NativeEndian::from_slice_i32 as the data is not mutable,
// and that is not needed as the data is already in native endian
@ -230,14 +232,14 @@ unsafe fn send_elements<W>(writer: &mut W, elt_tag: Tag, length: usize, data: *c
_ => {
let mut data = data;
for _ in 0..length {
send_value(writer, elt_tag, &mut data)?;
send_value(writer, elt_tag, &mut data, write_tags)?;
}
}
}
Ok(())
}
unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const ())
unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const (), write_tags: bool)
-> Result<(), Error<W::WriteError>>
where W: Write + ?Sized
{
@ -248,8 +250,9 @@ unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const ())
$map
})
}
if write_tags {
writer.write_u8(tag.as_u8())?;
}
match tag {
Tag::None => Ok(()),
Tag::Bool =>
@ -269,12 +272,14 @@ unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const ())
writer.write_bytes((*ptr).as_ref())),
Tag::Tuple(it, arity) => {
let mut it = it.clone();
if write_tags {
writer.write_u8(arity)?;
}
let mut max_alignment = 0;
for _ in 0..arity {
let tag = it.next().expect("truncated tag");
max_alignment = core::cmp::max(max_alignment, tag.alignment());
send_value(writer, tag, data)?
send_value(writer, tag, data, write_tags)?
}
*data = round_up_const(*data, max_alignment);
Ok(())
@ -286,11 +291,13 @@ unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const ())
let length = (**ptr).length as usize;
writer.write_u32((**ptr).length)?;
let tag = it.clone().next().expect("truncated tag");
send_elements(writer, tag, length, (**ptr).elements)
send_elements(writer, tag, length, (**ptr).elements, write_tags)
})
}
Tag::Array(it, num_dims) => {
if write_tags {
writer.write_u8(num_dims)?;
}
consume_value!(*const(), |buffer| {
let elt_tag = it.clone().next().expect("truncated tag");
@ -302,14 +309,14 @@ unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const ())
})
}
let length = total_len as usize;
send_elements(writer, elt_tag, length, *buffer)
send_elements(writer, elt_tag, length, *buffer, write_tags)
})
}
Tag::Range(it) => {
let tag = it.clone().next().expect("truncated tag");
send_value(writer, tag, data)?;
send_value(writer, tag, data)?;
send_value(writer, tag, data)?;
send_value(writer, tag, data, write_tags)?;
send_value(writer, tag, data, write_tags)?;
send_value(writer, tag, data, write_tags)?;
Ok(())
}
Tag::Keyword(it) => {
@ -319,7 +326,7 @@ unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const ())
writer.write_string(str::from_utf8((*ptr).name.as_ref()).unwrap())?;
let tag = it.clone().next().expect("truncated tag");
let mut data = ptr.offset(1) as *const ();
send_value(writer, tag, &mut data)
send_value(writer, tag, &mut data, write_tags)
})
// Tag::Keyword never appears in composite types, so we don't have
// to accurately advance data.
@ -333,7 +340,7 @@ unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const ())
}
}
pub fn send_args<W>(writer: &mut W, service: u32, tag_bytes: &[u8], data: *const *const ())
pub fn send_args<W>(writer: &mut W, service: u32, tag_bytes: &[u8], data: *const *const (), write_tags: bool)
-> Result<(), Error<W::WriteError>>
where W: Write + ?Sized
{
@ -350,7 +357,7 @@ pub fn send_args<W>(writer: &mut W, service: u32, tag_bytes: &[u8], data: *const
for index in 0.. {
if let Some(arg_tag) = args_it.next() {
let mut data = unsafe { *data.offset(index) };
unsafe { send_value(writer, arg_tag, &mut data)? };
unsafe { send_value(writer, arg_tag, &mut data, write_tags)? };
} else {
break
}
@ -482,7 +489,7 @@ mod tag {
#[derive(Debug, Clone, Copy)]
pub struct TagIterator<'a> {
data: &'a [u8]
pub data: &'a [u8]
}
impl<'a> TagIterator<'a> {

10
artiq/firmware/runtime/kernel.rs
View File

@ -307,8 +307,7 @@ pub mod subkernel {
pub struct Message {
from_id: u32,
pub tag_count: u8,
pub tag: u8,
pub count: u8,
pub data: Vec<u8>
}
@ -334,9 +333,8 @@ pub mod subkernel {
None => unsafe {
CURRENT_MESSAGES.insert(id, Message {
from_id: id,
tag_count: data[0],
tag: data[1],
data: data[2..length].to_vec()
count: data[0],
data: data[1..length].to_vec()
});
}
};
@ -404,7 +402,7 @@ pub mod subkernel {
let destination = unsafe { SUBKERNELS.get(&id).unwrap().destination };
// reuse rpc code for sending arbitrary data
rpc::send_args(&mut writer, 0, tag, message)?;
rpc::send_args(&mut writer, 0, tag, message, false)?;
// skip service tag, but overwrite first byte with tag count
let data = &mut writer.into_inner()[3..];
data[0] = count;

24
artiq/firmware/runtime/session.rs
View File

@ -502,7 +502,7 @@ fn process_kern_message(io: &Io, aux_mutex: &Mutex,
None => unexpected!("unexpected RPC in flash kernel"),
Some(ref mut stream) => {
host_write(stream, host::Reply::RpcRequest { async: async })?;
rpc::send_args(stream, service, tag, data)?;
rpc::send_args(stream, service, tag, data, true)?;
if !async {
session.kernel_state = KernelState::RpcWait
}
@ -608,10 +608,10 @@ fn process_kern_message(io: &Io, aux_mutex: &Mutex,
kern_acknowledge()
}
#[cfg(has_drtio)]
&kern::SubkernelMsgRecvRequest { id, timeout } => {
&kern::SubkernelMsgRecvRequest { id, timeout, tags } => {
let message_received = subkernel::message_await(io, _subkernel_mutex, id, timeout);
let (status, count) = match message_received {
Ok(ref message) => (kern::SubkernelStatus::NoError, message.tag_count),
Ok(ref message) => (kern::SubkernelStatus::NoError, message.count),
Err(SubkernelError::Timeout) => (kern::SubkernelStatus::Timeout, 0),
Err(SubkernelError::IncorrectState) => (kern::SubkernelStatus::IncorrectState, 0),
Err(SubkernelError::SubkernelFinished) => {
@ -628,11 +628,11 @@ fn process_kern_message(io: &Io, aux_mutex: &Mutex,
}
Err(_) => (kern::SubkernelStatus::OtherError, 0)
};
kern_send(io, &kern::SubkernelMsgRecvReply { status: status, count: count })?;
kern_send(io, &kern::SubkernelMsgRecvReply { status: status, count: count})?;
if let Ok(message) = message_received {
// receive code almost identical to RPC recv, except we are not reading from a stream
let mut reader = Cursor::new(message.data);
let mut tag: [u8; 1] = [message.tag];
let mut current_tags = tags;
let mut i = 0;
loop {
// kernel has to consume all arguments in the whole message
@ -643,7 +643,7 @@ fn process_kern_message(io: &Io, aux_mutex: &Mutex,
"expected root value slot from kernel CPU, not {:?}", other)
}
})?;
let res = rpc::recv_return(&mut reader, &tag, slot, &|size| -> Result<_, Error<SchedError>> {
let res = rpc::recv_return(&mut reader, current_tags, slot, &|size| -> Result<_, Error<SchedError>> {
if size == 0 {
return Ok(0 as *mut ())
}
@ -657,17 +657,19 @@ fn process_kern_message(io: &Io, aux_mutex: &Mutex,
})?)
});
match res {
Ok(_) => kern_send(io, &kern::RpcRecvReply(Ok(0)))?,
Err(_) => unexpected!("expected valid subkernel message data")
};
Ok(new_tags) => {
kern_send(io, &kern::RpcRecvReply(Ok(0)))?;
i += 1;
if i < message.tag_count {
if i < message.count {
// update the tag for next read
tag[0] = reader.read_u8()?;
current_tags = new_tags;
} else {
// should be done by then
break;
}
},
Err(_) => unexpected!("expected valid subkernel message data")
};
}
Ok(())
} else {

47
artiq/firmware/satman/kernel.rs
View File

@ -6,7 +6,7 @@ use board_artiq::{mailbox, spi};
use board_misoc::{csr, clock, i2c};
use proto_artiq::{kernel_proto as kern, session_proto::Reply::KernelException as HostKernelException, rpc_proto as rpc};
use eh::eh_artiq;
use io::{Cursor, ProtoRead};
use io::Cursor;
use kernel::eh_artiq::StackPointerBacktrace;
use ::{cricon_select, RtioMaster};
@ -52,12 +52,12 @@ mod kernel_cpu {
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
#[derive(Debug, Clone, PartialEq, Eq)]
enum KernelState {
Absent,
Loaded,
Running,
MsgAwait { max_time: u64 },
MsgAwait { max_time: u64, tags: Vec<u8> },
MsgSending
}
@ -99,7 +99,6 @@ pub struct Sliceable {
/* represents interkernel messages */
struct Message {
count: u8,
tag: u8,
data: Vec<u8>
}
@ -201,8 +200,7 @@ impl MessageManager {
None => {
self.in_buffer = Some(Message {
count: data[0],
tag: data[1],
data: data[2..length].to_vec()
data: data[1..length].to_vec()
});
}
};
@ -264,7 +262,7 @@ impl MessageManager {
pub fn accept_outgoing(&mut self, count: u8, tag: &[u8], data: *const *const ()) -> Result<(), Error> {
let mut writer = Cursor::new(Vec::new());
rpc::send_args(&mut writer, 0, tag, data)?;
rpc::send_args(&mut writer, 0, tag, data, false)?;
// skip service tag, but write the count
let mut data = writer.into_inner().split_off(3);
data[0] = count;
@ -507,17 +505,18 @@ impl Manager {
}
fn process_external_messages(&mut self) -> Result<(), Error> {
match self.session.kernel_state {
KernelState::MsgAwait { max_time } => {
if clock::get_ms() > max_time {
match &self.session.kernel_state {
KernelState::MsgAwait { max_time, tags } => {
if clock::get_ms() > *max_time {
kern_send(&kern::SubkernelMsgRecvReply { status: kern::SubkernelStatus::Timeout, count: 0 })?;
self.session.kernel_state = KernelState::Running;
return Ok(())
}
if let Some(message) = self.session.messages.get_incoming() {
kern_send(&kern::SubkernelMsgRecvReply { status: kern::SubkernelStatus::NoError, count: message.count })?;
let tags = tags.clone();
self.session.kernel_state = KernelState::Running;
pass_message_to_kernel(&message)
pass_message_to_kernel(&message, &tags)
} else {
Err(Error::AwaitingMessage)
}
@ -538,7 +537,7 @@ impl Manager {
// returns Ok(with_exception) on finish
// None if the kernel is still running
kern_recv(|request| {
match (request, self.session.kernel_state) {
match (request, &self.session.kernel_state) {
(&kern::LoadReply(_), KernelState::Loaded) => {
// We're standing by; ignore the message.
return Ok(None)
@ -611,9 +610,9 @@ impl Manager {
Ok(())
}
&kern::SubkernelMsgRecvRequest { id: _, timeout } => {
&kern::SubkernelMsgRecvRequest { id: _, timeout, tags } => {
let max_time = clock::get_ms() + timeout as u64;
self.session.kernel_state = KernelState::MsgAwait { max_time: max_time };
self.session.kernel_state = KernelState::MsgAwait { max_time: max_time, tags: tags.to_vec() };
Ok(())
},
@ -695,10 +694,9 @@ fn slice_kernel_exception(exceptions: &[Option<eh_artiq::Exception>],
}
}
fn pass_message_to_kernel(message: &Message) -> Result<(), Error> {
fn pass_message_to_kernel(message: &Message, tags: &[u8]) -> Result<(), Error> {
let mut reader = Cursor::new(&message.data);
let mut tag: [u8; 1] = [message.tag];
let count = message.count;
let mut current_tags = tags;
let mut i = 0;
loop {
let slot = kern_recv_w_timeout(100, |reply| {
@ -712,8 +710,7 @@ fn pass_message_to_kernel(message: &Message) -> Result<(), Error> {
"expected root value slot from kernel CPU, not {:?}", other)
}
})?;
let res = rpc::recv_return(&mut reader, &tag, slot, &|size| -> Result<_, Error> {
let res = rpc::recv_return(&mut reader, current_tags, slot, &|size| -> Result<_, Error> {
if size == 0 {
return Ok(0 as *mut ())
}
@ -735,17 +732,19 @@ fn pass_message_to_kernel(message: &Message) -> Result<(), Error> {
})?)
});
match res {
Ok(_) => kern_send(&kern::RpcRecvReply(Ok(0)))?,
Err(_) => unexpected!("expected valid subkernel message data")
};
Ok(new_tags) => {
kern_send(&kern::RpcRecvReply(Ok(0)))?;
i += 1;
if i < count {
if i < message.count {
// update the tag for next read
tag[0] = reader.read_u8()?;
current_tags = new_tags;
} else {
// should be done by then
break;
}
},
Err(_) => unexpected!("expected valid subkernel message data")
};
}
Ok(())
}

4
artiq/test/lit/embedding/subkernel_return.py
View File

@ -9,13 +9,13 @@ def entrypoint():
# CHECK: call void @subkernel_load_run\(i32 1, i1 true\), !dbg !.
# CHECK-NOT: call void @subkernel_send_message\(.*\), !dbg !.
returning()
# CHECK: call i8 @subkernel_await_message\(i32 1, i64 10000, i8 1, i8 1\), !dbg !.
# CHECK: call i8 @subkernel_await_message\(i32 1, i64 10000, { i8\*, i32 }\* nonnull .*, i8 1, i8 1\), !dbg !.
# CHECK: call void @subkernel_await_finish\(i32 1, i64 10000\), !dbg !.
subkernel_await(returning)
# CHECK-L: declare void @subkernel_load_run(i32, i1) local_unnamed_addr
# CHECK-NOT-L: declare void @subkernel_send_message(i32, i8, { i8*, i32 }*, i8**) local_unnamed_addr
# CHECK-L: declare i8 @subkernel_await_message(i32, i64, i8, i8) local_unnamed_addr
# CHECK-L: declare i8 @subkernel_await_message(i32, i64, { i8*, i32 }*, i8, i8) local_unnamed_addr
# CHECK-L: declare void @subkernel_await_finish(i32, i64) local_unnamed_addr
@subkernel(destination=1)
def returning() -> TInt32:

4
artiq/test/lit/embedding/subkernel_return_none.py
View File

@ -10,13 +10,13 @@ def entrypoint():
# CHECK-NOT: call void @subkernel_send_message\(.*\), !dbg !.
returning_none()
# CHECK: call void @subkernel_await_finish\(i32 1, i64 10000\), !dbg !.
# CHECK-NOT: call void @subkernel_await_message\(i32 1, i64 10000\), !dbg !.
# CHECK-NOT: call i8 @subkernel_await_message\(i32 1, i64 10000\, .*\), !dbg !.
subkernel_await(returning_none)
# CHECK-L: declare void @subkernel_load_run(i32, i1) local_unnamed_addr
# CHECK-NOT-L: declare void @subkernel_send_message(i32, { i8*, i32 }*, i8**) local_unnamed_addr
# CHECK-L: declare void @subkernel_await_finish(i32, i64) local_unnamed_addr
# CHECK-NOT-L: declare void @subkernel_await_message(i32, i64) local_unnamed_addr
# CHECK-NOT-L: declare i8 @subkernel_await_message(i32, i64, { i8*, i32 }*, i8, i8) local_unnamed_addr
@subkernel(destination=1)
def returning_none() -> TNone:
pass