From c366756a8537ef998d32c1ef57098d5aae7ca92f Mon Sep 17 00:00:00 2001 From: Andrew Zhogin Date: Mon, 26 Aug 2024 16:45:15 +0300 Subject: AsyncDrop implementation using shim codegen of async_drop_in_place::{closure}, scoped async drop added. --- compiler/rustc_middle/src/ty/context.rs | 5 +- compiler/rustc_middle/src/ty/instance.rs | 95 +++++++++++++++-- compiler/rustc_middle/src/ty/mod.rs | 58 ++++++++++- compiler/rustc_middle/src/ty/sty.rs | 172 ++++++++----------------------- compiler/rustc_middle/src/ty/util.rs | 109 +++++--------------- 5 files changed, 214 insertions(+), 225 deletions(-) (limited to 'compiler/rustc_middle/src/ty') diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs index e8dad1e056c..23ee6514622 100644 --- a/compiler/rustc_middle/src/ty/context.rs +++ b/compiler/rustc_middle/src/ty/context.rs @@ -717,7 +717,6 @@ macro_rules! bidirectional_lang_item_map { bidirectional_lang_item_map! { // tidy-alphabetical-start - AsyncDestruct, AsyncFn, AsyncFnKindHelper, AsyncFnKindUpvars, @@ -1715,6 +1714,10 @@ impl<'tcx> TyCtxt<'tcx> { self.coroutine_kind(def_id).is_some() } + pub fn is_async_drop_in_place_coroutine(self, def_id: DefId) -> bool { + self.is_lang_item(self.parent(def_id), LangItem::AsyncDropInPlace) + } + /// Returns the movability of the coroutine of `def_id`, or panics /// if given a `def_id` that is not a coroutine. pub fn coroutine_movability(self, def_id: DefId) -> hir::Movability { diff --git a/compiler/rustc_middle/src/ty/instance.rs b/compiler/rustc_middle/src/ty/instance.rs index faad0a82acb..d660e7d0d60 100644 --- a/compiler/rustc_middle/src/ty/instance.rs +++ b/compiler/rustc_middle/src/ty/instance.rs @@ -147,6 +147,9 @@ pub enum InstanceKind<'tcx> { /// native support. ThreadLocalShim(DefId), + /// Proxy shim for async drop of future (def_id, proxy_cor_ty, impl_cor_ty) + FutureDropPollShim(DefId, Ty<'tcx>, Ty<'tcx>), + /// `core::ptr::drop_in_place::`. /// /// The `DefId` is for `core::ptr::drop_in_place`. @@ -173,7 +176,13 @@ pub enum InstanceKind<'tcx> { /// /// The `DefId` is for `core::future::async_drop::async_drop_in_place`, the `Ty` /// is the type `T`. - AsyncDropGlueCtorShim(DefId, Option>), + AsyncDropGlueCtorShim(DefId, Ty<'tcx>), + + /// `core::future::async_drop::async_drop_in_place::<'_, T>::{closure}`. + /// + /// async_drop_in_place poll function implementation (for generated coroutine). + /// `Ty` here is `async_drop_in_place::{closure}` coroutine type, not just `T` + AsyncDropGlue(DefId, Ty<'tcx>), } impl<'tcx> Instance<'tcx> { @@ -221,7 +230,9 @@ impl<'tcx> Instance<'tcx> { .upstream_monomorphizations_for(def) .and_then(|monos| monos.get(&self.args).cloned()), InstanceKind::DropGlue(_, Some(_)) => tcx.upstream_drop_glue_for(self.args), - InstanceKind::AsyncDropGlueCtorShim(_, Some(_)) => { + InstanceKind::AsyncDropGlue(_, _) => None, + InstanceKind::FutureDropPollShim(_, _, _) => None, + InstanceKind::AsyncDropGlueCtorShim(_, _) => { tcx.upstream_async_drop_glue_for(self.args) } _ => None, @@ -248,6 +259,8 @@ impl<'tcx> InstanceKind<'tcx> { | InstanceKind::DropGlue(def_id, _) | InstanceKind::CloneShim(def_id, _) | InstanceKind::FnPtrAddrShim(def_id, _) + | InstanceKind::FutureDropPollShim(def_id, _, _) + | InstanceKind::AsyncDropGlue(def_id, _) | InstanceKind::AsyncDropGlueCtorShim(def_id, _) => def_id, } } @@ -257,7 +270,9 @@ impl<'tcx> InstanceKind<'tcx> { match self { ty::InstanceKind::Item(def) => Some(def), ty::InstanceKind::DropGlue(def_id, Some(_)) - | InstanceKind::AsyncDropGlueCtorShim(def_id, Some(_)) + | InstanceKind::AsyncDropGlueCtorShim(def_id, _) + | InstanceKind::AsyncDropGlue(def_id, _) + | InstanceKind::FutureDropPollShim(def_id, ..) | InstanceKind::ThreadLocalShim(def_id) => Some(def_id), InstanceKind::VTableShim(..) | InstanceKind::ReifyShim(..) @@ -267,7 +282,6 @@ impl<'tcx> InstanceKind<'tcx> { | InstanceKind::ClosureOnceShim { .. } | ty::InstanceKind::ConstructCoroutineInClosureShim { .. } | InstanceKind::DropGlue(..) - | InstanceKind::AsyncDropGlueCtorShim(..) | InstanceKind::CloneShim(..) | InstanceKind::FnPtrAddrShim(..) => None, } @@ -292,7 +306,9 @@ impl<'tcx> InstanceKind<'tcx> { let def_id = match *self { ty::InstanceKind::Item(def) => def, ty::InstanceKind::DropGlue(_, Some(_)) => return false, - ty::InstanceKind::AsyncDropGlueCtorShim(_, Some(_)) => return false, + ty::InstanceKind::AsyncDropGlueCtorShim(_, ty) => return ty.is_coroutine(), + ty::InstanceKind::FutureDropPollShim(_, _, _) => return false, + ty::InstanceKind::AsyncDropGlue(_, _) => return false, ty::InstanceKind::ThreadLocalShim(_) => return false, _ => return true, }; @@ -325,11 +341,12 @@ impl<'tcx> InstanceKind<'tcx> { | InstanceKind::FnPtrAddrShim(..) | InstanceKind::FnPtrShim(..) | InstanceKind::DropGlue(_, Some(_)) - | InstanceKind::AsyncDropGlueCtorShim(_, Some(_)) => false, + | InstanceKind::FutureDropPollShim(..) + | InstanceKind::AsyncDropGlue(_, _) => false, + InstanceKind::AsyncDropGlueCtorShim(_, _) => false, InstanceKind::ClosureOnceShim { .. } | InstanceKind::ConstructCoroutineInClosureShim { .. } | InstanceKind::DropGlue(..) - | InstanceKind::AsyncDropGlueCtorShim(..) | InstanceKind::Item(_) | InstanceKind::Intrinsic(..) | InstanceKind::ReifyShim(..) @@ -406,8 +423,11 @@ pub fn fmt_instance( InstanceKind::DropGlue(_, Some(ty)) => write!(f, " - shim(Some({ty}))"), InstanceKind::CloneShim(_, ty) => write!(f, " - shim({ty})"), InstanceKind::FnPtrAddrShim(_, ty) => write!(f, " - shim({ty})"), - InstanceKind::AsyncDropGlueCtorShim(_, None) => write!(f, " - shim(None)"), - InstanceKind::AsyncDropGlueCtorShim(_, Some(ty)) => write!(f, " - shim(Some({ty}))"), + InstanceKind::FutureDropPollShim(_, proxy_ty, impl_ty) => { + write!(f, " - dropshim({proxy_ty}-{impl_ty})") + } + InstanceKind::AsyncDropGlue(_, ty) => write!(f, " - shim({ty})"), + InstanceKind::AsyncDropGlueCtorShim(_, ty) => write!(f, " - shim(Some({ty}))"), } } @@ -425,6 +445,51 @@ impl<'tcx> fmt::Display for Instance<'tcx> { } } +// async_drop_in_place::coroutine.poll, when T is a standart coroutine, +// should be resolved to this coroutine's future_drop_poll (through FutureDropPollShim proxy). +// async_drop_in_place::coroutine>::coroutine.poll, +// when T is a standart coroutine, should be resolved to this coroutine's future_drop_poll. +// async_drop_in_place::coroutine>::coroutine.poll, +// when T is not a coroutine, should be resolved to the innermost +// async_drop_in_place::coroutine's poll function (through FutureDropPollShim proxy) +fn resolve_async_drop_poll<'tcx>(mut cor_ty: Ty<'tcx>) -> Instance<'tcx> { + let first_cor = cor_ty; + let ty::Coroutine(poll_def_id, proxy_args) = first_cor.kind() else { + bug!(); + }; + let poll_def_id = *poll_def_id; + let mut child_ty = cor_ty; + loop { + if let ty::Coroutine(child_def, child_args) = child_ty.kind() { + cor_ty = child_ty; + if *child_def == poll_def_id { + child_ty = child_args.first().unwrap().expect_ty(); + continue; + } else { + return Instance { + def: ty::InstanceKind::FutureDropPollShim(poll_def_id, first_cor, cor_ty), + args: proxy_args, + }; + } + } else { + let ty::Coroutine(_, child_args) = cor_ty.kind() else { + bug!(); + }; + if first_cor != cor_ty { + return Instance { + def: ty::InstanceKind::FutureDropPollShim(poll_def_id, first_cor, cor_ty), + args: proxy_args, + }; + } else { + return Instance { + def: ty::InstanceKind::AsyncDropGlue(poll_def_id, cor_ty), + args: child_args, + }; + } + } + } +} + impl<'tcx> Instance<'tcx> { pub fn new(def_id: DefId, args: GenericArgsRef<'tcx>) -> Instance<'tcx> { assert!( @@ -736,6 +801,15 @@ impl<'tcx> Instance<'tcx> { ) } + pub fn resolve_async_drop_in_place_poll( + tcx: TyCtxt<'tcx>, + def_id: DefId, + ty: Ty<'tcx>, + ) -> ty::Instance<'tcx> { + let args = tcx.mk_args(&[ty.into()]); + Instance::expect_resolve(tcx, ty::TypingEnv::fully_monomorphized(), def_id, args, DUMMY_SP) + } + #[instrument(level = "debug", skip(tcx), ret)] pub fn fn_once_adapter_instance( tcx: TyCtxt<'tcx>, @@ -800,6 +874,9 @@ impl<'tcx> Instance<'tcx> { }; if tcx.is_lang_item(trait_item_id, coroutine_callable_item) { + if tcx.is_async_drop_in_place_coroutine(coroutine_def_id) { + return Some(resolve_async_drop_poll(rcvr_args.type_at(0))); + } let ty::Coroutine(_, id_args) = *tcx.type_of(coroutine_def_id).skip_binder().kind() else { bug!() diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs index be00c0e116d..eba6d61ba7d 100644 --- a/compiler/rustc_middle/src/ty/mod.rs +++ b/compiler/rustc_middle/src/ty/mod.rs @@ -17,7 +17,7 @@ use std::hash::{Hash, Hasher}; use std::marker::PhantomData; use std::num::NonZero; use std::ptr::NonNull; -use std::{fmt, str}; +use std::{fmt, iter, str}; pub use adt::*; pub use assoc::*; @@ -39,6 +39,7 @@ use rustc_hir::LangItem; use rustc_hir::def::{CtorKind, CtorOf, DefKind, DocLinkResMap, LifetimeRes, Res}; use rustc_hir::def_id::{CrateNum, DefId, DefIdMap, LocalDefId, LocalDefIdMap}; use rustc_index::IndexVec; +use rustc_index::bit_set::BitMatrix; use rustc_macros::{ Decodable, Encodable, HashStable, TyDecodable, TyEncodable, TypeFoldable, TypeVisitable, extension, @@ -103,7 +104,7 @@ pub use self::visit::*; use crate::error::{OpaqueHiddenTypeMismatch, TypeMismatchReason}; use crate::metadata::ModChild; use crate::middle::privacy::EffectiveVisibilities; -use crate::mir::{Body, CoroutineLayout}; +use crate::mir::{Body, CoroutineLayout, CoroutineSavedLocal, SourceInfo}; use crate::query::{IntoQueryParam, Providers}; use crate::ty; use crate::ty::codec::{TyDecoder, TyEncoder}; @@ -1739,11 +1740,13 @@ impl<'tcx> TyCtxt<'tcx> { | ty::InstanceKind::Virtual(..) | ty::InstanceKind::ClosureOnceShim { .. } | ty::InstanceKind::ConstructCoroutineInClosureShim { .. } + | ty::InstanceKind::FutureDropPollShim(..) | ty::InstanceKind::DropGlue(..) | ty::InstanceKind::CloneShim(..) | ty::InstanceKind::ThreadLocalShim(..) | ty::InstanceKind::FnPtrAddrShim(..) - | ty::InstanceKind::AsyncDropGlueCtorShim(..) => self.mir_shims(instance), + | ty::InstanceKind::AsyncDropGlueCtorShim(..) + | ty::InstanceKind::AsyncDropGlue(..) => self.mir_shims(instance), } } @@ -1859,12 +1862,12 @@ impl<'tcx> TyCtxt<'tcx> { self.def_kind(trait_def_id) == DefKind::TraitAlias } - /// Returns layout of a coroutine. Layout might be unavailable if the + /// Returns layout of a non-async-drop coroutine. Layout might be unavailable if the /// coroutine is tainted by errors. /// /// Takes `coroutine_kind` which can be acquired from the `CoroutineArgs::kind_ty`, /// e.g. `args.as_coroutine().kind_ty()`. - pub fn coroutine_layout( + fn ordinary_coroutine_layout( self, def_id: DefId, coroutine_kind_ty: Ty<'tcx>, @@ -1898,6 +1901,51 @@ impl<'tcx> TyCtxt<'tcx> { } } + /// Returns layout of a `async_drop_in_place::{closure}` coroutine + /// (returned from `async fn async_drop_in_place(..)`). + /// Layout might be unavailable if the coroutine is tainted by errors. + fn async_drop_coroutine_layout( + self, + def_id: DefId, + args: GenericArgsRef<'tcx>, + ) -> Option<&'tcx CoroutineLayout<'tcx>> { + let instance = InstanceKind::AsyncDropGlue(def_id, Ty::new_coroutine(self, def_id, args)); + self.mir_shims(instance).coroutine_layout_raw() + } + + /// Returns layout of a coroutine. Layout might be unavailable if the + /// coroutine is tainted by errors. + pub fn coroutine_layout( + self, + def_id: DefId, + args: GenericArgsRef<'tcx>, + ) -> Option<&'tcx CoroutineLayout<'tcx>> { + if self.is_async_drop_in_place_coroutine(def_id) { + // layout of `async_drop_in_place::{closure}` in case, + // when T is a coroutine, contains this internal coroutine's ptr in upvars + // and doesn't require any locals. Here is an `empty coroutine's layout` + let arg_cor_ty = args.first().unwrap().expect_ty(); + if arg_cor_ty.is_coroutine() { + let span = self.def_span(def_id); + let source_info = SourceInfo::outermost(span); + let variant_fields: IndexVec> = + iter::repeat(IndexVec::new()).take(CoroutineArgs::RESERVED_VARIANTS).collect(); + let proxy_layout = CoroutineLayout { + field_tys: [].into(), + field_names: [].into(), + variant_fields, + variant_source_info: [source_info].into(), + storage_conflicts: BitMatrix::new(0, 0), + }; + return Some(self.arena.alloc(proxy_layout)); + } else { + self.async_drop_coroutine_layout(def_id, args) + } + } else { + self.ordinary_coroutine_layout(def_id, args.as_coroutine().kind_ty()) + } + } + /// Given the `DefId` of an impl, returns the `DefId` of the trait it implements. /// If it implements no trait, returns `None`. pub fn trait_id_of_impl(self, def_id: DefId) -> Option { diff --git a/compiler/rustc_middle/src/ty/sty.rs b/compiler/rustc_middle/src/ty/sty.rs index affb7b31ae1..b6043bc740f 100644 --- a/compiler/rustc_middle/src/ty/sty.rs +++ b/compiler/rustc_middle/src/ty/sty.rs @@ -4,7 +4,6 @@ use std::assert_matches::debug_assert_matches; use std::borrow::Cow; -use std::iter; use std::ops::{ControlFlow, Range}; use hir::def::{CtorKind, DefKind}; @@ -19,7 +18,7 @@ use rustc_type_ir::TyKind::*; use rustc_type_ir::walk::TypeWalker; use rustc_type_ir::{self as ir, BoundVar, CollectAndApply, DynKind, TypeVisitableExt, elaborate}; use tracing::instrument; -use ty::util::{AsyncDropGlueMorphology, IntTypeExt}; +use ty::util::IntTypeExt; use super::GenericParamDefKind; use crate::infer::canonical::Canonical; @@ -78,8 +77,7 @@ impl<'tcx> ty::CoroutineArgs> { #[inline] fn variant_range(&self, def_id: DefId, tcx: TyCtxt<'tcx>) -> Range { // FIXME requires optimized MIR - FIRST_VARIANT - ..tcx.coroutine_layout(def_id, tcx.types.unit).unwrap().variant_fields.next_index() + FIRST_VARIANT..tcx.coroutine_layout(def_id, self.args).unwrap().variant_fields.next_index() } /// The discriminant for the given variant. Panics if the `variant_index` is @@ -139,10 +137,14 @@ impl<'tcx> ty::CoroutineArgs> { def_id: DefId, tcx: TyCtxt<'tcx>, ) -> impl Iterator>> { - let layout = tcx.coroutine_layout(def_id, self.kind_ty()).unwrap(); + let layout = tcx.coroutine_layout(def_id, self.args).unwrap(); layout.variant_fields.iter().map(move |variant| { variant.iter().map(move |field| { - ty::EarlyBinder::bind(layout.field_tys[*field].ty).instantiate(tcx, self.args) + if tcx.is_async_drop_in_place_coroutine(def_id) { + layout.field_tys[*field].ty + } else { + ty::EarlyBinder::bind(layout.field_tys[*field].ty).instantiate(tcx, self.args) + } }) }) } @@ -1046,10 +1048,6 @@ impl<'tcx> rustc_type_ir::inherent::Ty> for Ty<'tcx> { self.discriminant_ty(interner) } - fn async_destructor_ty(self, interner: TyCtxt<'tcx>) -> Ty<'tcx> { - self.async_destructor_ty(interner) - } - fn has_unsafe_fields(self) -> bool { Ty::has_unsafe_fields(self) } @@ -1419,6 +1417,34 @@ impl<'tcx> Ty<'tcx> { cf.is_break() } + /// Returns the deepest `async_drop_in_place::{closure}` implementation. + /// + /// `async_drop_in_place::{closure}`, when T is a coroutine, is a proxy-impl + /// to call async drop poll from impl coroutine. + pub fn find_async_drop_impl_coroutine)>( + self, + tcx: TyCtxt<'tcx>, + mut f: F, + ) -> Ty<'tcx> { + assert!(self.is_coroutine()); + let mut cor_ty = self; + let mut ty = cor_ty; + loop { + if let ty::Coroutine(def_id, args) = ty.kind() { + cor_ty = ty; + f(ty); + if tcx.is_async_drop_in_place_coroutine(*def_id) { + ty = args.first().unwrap().expect_ty(); + continue; + } else { + return cor_ty; + } + } else { + return cor_ty; + } + } + } + /// Returns the type and mutability of `*ty`. /// /// The parameter `explicit` indicates if this is an *explicit* dereference. @@ -1560,125 +1586,6 @@ impl<'tcx> Ty<'tcx> { } } - /// Returns the type of the async destructor of this type. - pub fn async_destructor_ty(self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> { - match self.async_drop_glue_morphology(tcx) { - AsyncDropGlueMorphology::Noop => { - return Ty::async_destructor_combinator(tcx, LangItem::AsyncDropNoop) - .instantiate_identity(); - } - AsyncDropGlueMorphology::DeferredDropInPlace => { - let drop_in_place = - Ty::async_destructor_combinator(tcx, LangItem::AsyncDropDeferredDropInPlace) - .instantiate(tcx, &[self.into()]); - return Ty::async_destructor_combinator(tcx, LangItem::AsyncDropFuse) - .instantiate(tcx, &[drop_in_place.into()]); - } - AsyncDropGlueMorphology::Custom => (), - } - - match *self.kind() { - ty::Param(_) | ty::Alias(..) | ty::Infer(ty::TyVar(_)) => { - let assoc_items = tcx - .associated_item_def_ids(tcx.require_lang_item(LangItem::AsyncDestruct, None)); - Ty::new_projection(tcx, assoc_items[0], [self]) - } - - ty::Array(elem_ty, _) | ty::Slice(elem_ty) => { - let dtor = Ty::async_destructor_combinator(tcx, LangItem::AsyncDropSlice) - .instantiate(tcx, &[elem_ty.into()]); - Ty::async_destructor_combinator(tcx, LangItem::AsyncDropFuse) - .instantiate(tcx, &[dtor.into()]) - } - - ty::Adt(adt_def, args) if adt_def.is_enum() || adt_def.is_struct() => self - .adt_async_destructor_ty( - tcx, - adt_def.variants().iter().map(|v| v.fields.iter().map(|f| f.ty(tcx, args))), - ), - ty::Tuple(tys) => self.adt_async_destructor_ty(tcx, iter::once(tys)), - ty::Closure(_, args) => { - self.adt_async_destructor_ty(tcx, iter::once(args.as_closure().upvar_tys())) - } - ty::CoroutineClosure(_, args) => self - .adt_async_destructor_ty(tcx, iter::once(args.as_coroutine_closure().upvar_tys())), - - ty::Adt(adt_def, _) => { - assert!(adt_def.is_union()); - - let surface_drop = self.surface_async_dropper_ty(tcx).unwrap(); - - Ty::async_destructor_combinator(tcx, LangItem::AsyncDropFuse) - .instantiate(tcx, &[surface_drop.into()]) - } - - ty::Bound(..) - | ty::Foreign(_) - | ty::Placeholder(_) - | ty::Infer(ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) => { - bug!("`async_destructor_ty` applied to unexpected type: {self:?}") - } - - _ => bug!("`async_destructor_ty` is not yet implemented for type: {self:?}"), - } - } - - fn adt_async_destructor_ty(self, tcx: TyCtxt<'tcx>, variants: I) -> Ty<'tcx> - where - I: Iterator + ExactSizeIterator, - I::Item: IntoIterator>, - { - debug_assert_eq!(self.async_drop_glue_morphology(tcx), AsyncDropGlueMorphology::Custom); - - let defer = Ty::async_destructor_combinator(tcx, LangItem::AsyncDropDefer); - let chain = Ty::async_destructor_combinator(tcx, LangItem::AsyncDropChain); - - let noop = - Ty::async_destructor_combinator(tcx, LangItem::AsyncDropNoop).instantiate_identity(); - let either = Ty::async_destructor_combinator(tcx, LangItem::AsyncDropEither); - - let variants_dtor = variants - .into_iter() - .map(|variant| { - variant - .into_iter() - .map(|ty| defer.instantiate(tcx, &[ty.into()])) - .reduce(|acc, next| chain.instantiate(tcx, &[acc.into(), next.into()])) - .unwrap_or(noop) - }) - .reduce(|other, matched| { - either.instantiate(tcx, &[other.into(), matched.into(), self.into()]) - }) - .unwrap(); - - let dtor = if let Some(dropper_ty) = self.surface_async_dropper_ty(tcx) { - Ty::async_destructor_combinator(tcx, LangItem::AsyncDropChain) - .instantiate(tcx, &[dropper_ty.into(), variants_dtor.into()]) - } else { - variants_dtor - }; - - Ty::async_destructor_combinator(tcx, LangItem::AsyncDropFuse) - .instantiate(tcx, &[dtor.into()]) - } - - fn surface_async_dropper_ty(self, tcx: TyCtxt<'tcx>) -> Option> { - let adt_def = self.ty_adt_def()?; - let dropper = adt_def - .async_destructor(tcx) - .map(|_| LangItem::SurfaceAsyncDropInPlace) - .or_else(|| adt_def.destructor(tcx).map(|_| LangItem::AsyncDropSurfaceDropInPlace))?; - Some(Ty::async_destructor_combinator(tcx, dropper).instantiate(tcx, &[self.into()])) - } - - fn async_destructor_combinator( - tcx: TyCtxt<'tcx>, - lang_item: LangItem, - ) -> ty::EarlyBinder<'tcx, Ty<'tcx>> { - tcx.fn_sig(tcx.require_lang_item(lang_item, None)) - .map_bound(|fn_sig| fn_sig.output().no_bound_vars().unwrap()) - } - /// Returns the type of metadata for (potentially wide) pointers to this type, /// or the struct tail if the metadata type cannot be determined. pub fn ptr_metadata_ty_or_tail( @@ -2020,6 +1927,13 @@ impl<'tcx> Ty<'tcx> { } } + pub fn is_async_drop_in_place_coroutine(self, tcx: TyCtxt<'_>) -> bool { + match self.kind() { + ty::Coroutine(def, ..) => tcx.is_async_drop_in_place_coroutine(*def), + _ => false, + } + } + /// Returns `true` when the outermost type cannot be further normalized, /// resolved, or instantiated. This includes all primitive types, but also /// things like ADTs and trait objects, since even if their arguments or diff --git a/compiler/rustc_middle/src/ty/util.rs b/compiler/rustc_middle/src/ty/util.rs index 08cee1101d0..f46a1d4b22e 100644 --- a/compiler/rustc_middle/src/ty/util.rs +++ b/compiler/rustc_middle/src/ty/util.rs @@ -468,25 +468,6 @@ impl<'tcx> TyCtxt<'tcx> { Some(ty::AsyncDestructor { impl_did: dtor_candidate? }) } - /// Returns async drop glue morphology for a definition. To get async drop - /// glue morphology for a type see [`Ty::async_drop_glue_morphology`]. - // - // FIXME: consider making this a query - pub fn async_drop_glue_morphology(self, did: DefId) -> AsyncDropGlueMorphology { - let ty: Ty<'tcx> = self.type_of(did).instantiate_identity(); - - // Async drop glue morphology is an internal detail, so - // using `TypingMode::PostAnalysis` probably should be fine. - let typing_env = ty::TypingEnv::fully_monomorphized(); - if ty.needs_async_drop(self, typing_env) { - AsyncDropGlueMorphology::Custom - } else if ty.needs_drop(self, typing_env) { - AsyncDropGlueMorphology::DeferredDropInPlace - } else { - AsyncDropGlueMorphology::Noop - } - } - /// Returns the set of types that are required to be alive in /// order to run the destructor of `def` (see RFCs 769 and /// 1238). @@ -1114,18 +1095,6 @@ impl<'tcx> TypeFolder> for WeakAliasTypeExpander<'tcx> { } } -/// Indicates the form of `AsyncDestruct::Destructor`. Used to simplify async -/// drop glue for types not using async drop. -#[derive(Clone, Copy, PartialEq, Eq, Debug)] -pub enum AsyncDropGlueMorphology { - /// Async destructor simply does nothing - Noop, - /// Async destructor simply runs `drop_in_place` - DeferredDropInPlace, - /// Async destructor has custom logic - Custom, -} - impl<'tcx> Ty<'tcx> { /// Returns the `Size` for primitive types (bool, uint, int, char, float). pub fn primitive_size(self, tcx: TyCtxt<'tcx>) -> Size { @@ -1295,16 +1264,17 @@ impl<'tcx> Ty<'tcx> { } } - /// Get morphology of the async drop glue, needed for types which do not - /// use async drop. To get async drop glue morphology for a definition see - /// [`TyCtxt::async_drop_glue_morphology`]. Used for `AsyncDestruct::Destructor` - /// type construction. - // - // FIXME: implement optimization to not instantiate a certain morphology of - // async drop glue too soon to allow per type optimizations, see array case - // for more info. Perhaps then remove this method and use `needs_(async_)drop` - // instead. - pub fn async_drop_glue_morphology(self, tcx: TyCtxt<'tcx>) -> AsyncDropGlueMorphology { + /// Checks whether values of this type `T` implement the `AsyncDrop` trait. + pub fn is_async_drop(self, tcx: TyCtxt<'tcx>, typing_env: ty::TypingEnv<'tcx>) -> bool { + !self.is_trivially_not_async_drop() + && tcx.is_async_drop_raw(typing_env.as_query_input(self)) + } + + /// Fast path helper for testing if a type is `AsyncDrop`. + /// + /// Returning true means the type is known to be `!AsyncDrop`. Returning + /// `false` means nothing -- could be `AsyncDrop`, might not be. + fn is_trivially_not_async_drop(self) -> bool { match self.kind() { ty::Int(_) | ty::Uint(_) @@ -1316,46 +1286,26 @@ impl<'tcx> Ty<'tcx> { | ty::Ref(..) | ty::RawPtr(..) | ty::FnDef(..) - | ty::FnPtr(..) - | ty::Infer(ty::FreshIntTy(_)) - | ty::Infer(ty::FreshFloatTy(_)) => AsyncDropGlueMorphology::Noop, - + | ty::Error(_) + | ty::FnPtr(..) => true, // FIXME(unsafe_binders): ty::UnsafeBinder(_) => todo!(), - - ty::Tuple(tys) if tys.is_empty() => AsyncDropGlueMorphology::Noop, - ty::Adt(adt_def, _) if adt_def.is_manually_drop() => AsyncDropGlueMorphology::Noop, - - // Foreign types can never have destructors. - ty::Foreign(_) => AsyncDropGlueMorphology::Noop, - - // FIXME: implement dynamic types async drops - ty::Error(_) | ty::Dynamic(..) => AsyncDropGlueMorphology::DeferredDropInPlace, - - ty::Tuple(_) | ty::Array(_, _) | ty::Slice(_) => { - // Assume worst-case scenario, because we can instantiate async - // destructors in different orders: - // - // 1. Instantiate [T; N] with T = String and N = 0 - // 2. Instantiate <[String; 0] as AsyncDestruct>::Destructor - // - // And viceversa, thus we cannot rely on String not using async - // drop or array having zero (0) elements - AsyncDropGlueMorphology::Custom - } - ty::Pat(ty, _) => ty.async_drop_glue_morphology(tcx), - - ty::Adt(adt_def, _) => tcx.async_drop_glue_morphology(adt_def.did()), - - ty::Closure(did, _) - | ty::CoroutineClosure(did, _) - | ty::Coroutine(did, _) - | ty::CoroutineWitness(did, _) => tcx.async_drop_glue_morphology(*did), - - ty::Alias(..) | ty::Param(_) | ty::Bound(..) | ty::Placeholder(..) | ty::Infer(_) => { - // No specifics, but would usually mean forwarding async drop glue - AsyncDropGlueMorphology::Custom + ty::Tuple(fields) => fields.iter().all(Self::is_trivially_not_async_drop), + ty::Pat(elem_ty, _) | ty::Slice(elem_ty) | ty::Array(elem_ty, _) => { + elem_ty.is_trivially_not_async_drop() } + ty::Adt(..) + | ty::Bound(..) + | ty::Closure(..) + | ty::CoroutineClosure(..) + | ty::Dynamic(..) + | ty::Foreign(_) + | ty::Coroutine(..) + | ty::CoroutineWitness(..) + | ty::Infer(_) + | ty::Alias(..) + | ty::Param(_) + | ty::Placeholder(_) => false, } } @@ -1401,9 +1351,6 @@ impl<'tcx> Ty<'tcx> { /// (Note that this implies that if `ty` has an async destructor attached, /// then `needs_async_drop` will definitely return `true` for `ty`.) /// - /// When constructing `AsyncDestruct::Destructor` type, use - /// [`Ty::async_drop_glue_morphology`] instead. - // // FIXME(zetanumbers): Note that this method is used to check eligible types // in unions. #[inline] -- cgit 1.4.1-3-g733a5