rust/0001-Fix-Async-Generator-ABI.patch
2023-02-09 16:52:15 -08:00

56 lines
2.6 KiB
Diff

From ecf812777a260e35ec9cd0c7d9dbd17a3f5cf5f9 Mon Sep 17 00:00:00 2001
From: Arpad Borsos <swatinem@swatinem.de>
Date: Tue, 29 Nov 2022 23:17:08 +0100
Subject: [PATCH] Fix Async Generator ABI
This change was missed when making async generators implement `Future` directly.
It did not cause any problems in codegen so far, as `GeneratorState<(), Output>`
happens to have the same ABI as `Poll<Output>`.
---
compiler/rustc_ty_utils/src/abi.rs | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)
diff --git a/compiler/rustc_ty_utils/src/abi.rs b/compiler/rustc_ty_utils/src/abi.rs
index 73c7eb6992f0..d644cbccea11 100644
--- a/compiler/rustc_ty_utils/src/abi.rs
+++ b/compiler/rustc_ty_utils/src/abi.rs
@@ -85,7 +85,7 @@ fn fn_sig_for_fn_abi<'tcx>(
bound_vars,
)
}
- ty::Generator(_, substs, _) => {
+ ty::Generator(did, substs, _) => {
let sig = substs.as_generator().poly_sig();
let bound_vars = tcx.mk_bound_variable_kinds(
@@ -104,10 +104,22 @@ fn fn_sig_for_fn_abi<'tcx>(
let env_ty = tcx.mk_adt(pin_adt_ref, pin_substs);
let sig = sig.skip_binder();
- let state_did = tcx.require_lang_item(LangItem::GeneratorState, None);
- let state_adt_ref = tcx.adt_def(state_did);
- let state_substs = tcx.intern_substs(&[sig.yield_ty.into(), sig.return_ty.into()]);
- let ret_ty = tcx.mk_adt(state_adt_ref, state_substs);
+ // The `FnSig` and the `ret_ty` here is for a generators main
+ // `Generator::resume(...) -> GeneratorState` function in case we
+ // have an ordinary generator, or the `Future::poll(...) -> Poll`
+ // function in case this is a special generator backing an async construct.
+ let ret_ty = if tcx.generator_is_async(did) {
+ let state_did = tcx.require_lang_item(LangItem::Poll, None);
+ let state_adt_ref = tcx.adt_def(state_did);
+ let state_substs = tcx.intern_substs(&[sig.return_ty.into()]);
+ tcx.mk_adt(state_adt_ref, state_substs)
+ } else {
+ let state_did = tcx.require_lang_item(LangItem::GeneratorState, None);
+ let state_adt_ref = tcx.adt_def(state_did);
+ let state_substs = tcx.intern_substs(&[sig.yield_ty.into(), sig.return_ty.into()]);
+ tcx.mk_adt(state_adt_ref, state_substs)
+ };
+
ty::Binder::bind_with_vars(
tcx.mk_fn_sig(
[env_ty, sig.resume_ty].iter(),
--
2.39.1