From af10880f6b4a56e5f9a3c458878772f8eda19544 Mon Sep 17 00:00:00 2001 From: Daria Sukhonina Date: Mon, 17 Jun 2024 17:00:45 +0300 Subject: [PATCH 1/2] Make async drop code more consistent with regular drop code Fixes #126573 --- .../src/back/symbol_export.rs | 19 ++++++++--- compiler/rustc_middle/src/query/mod.rs | 33 +++++++++++++++---- compiler/rustc_middle/src/ty/instance.rs | 28 ++++++++++++++-- .../cfi/typeid/itanium_cxx_abi/transform.rs | 1 + 4 files changed, 67 insertions(+), 14 deletions(-) diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs index 1d61c15640910..c868904c5511c 100644 --- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs +++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs @@ -371,7 +371,7 @@ fn exported_symbols_provider_local( }) => { // A little sanity-check debug_assert_eq!( - args.non_erasable_generics(tcx, def_id).skip(1).next(), + args.non_erasable_generics(tcx, def_id).next(), Some(GenericArgKind::Type(ty)) ); symbols.push(( @@ -422,10 +422,7 @@ fn upstream_monomorphizations_provider( } ExportedSymbol::AsyncDropGlueCtorShim(ty) => { if let Some(async_drop_in_place_fn_def_id) = async_drop_in_place_fn_def_id { - ( - async_drop_in_place_fn_def_id, - tcx.mk_args(&[tcx.lifetimes.re_erased.into(), ty.into()]), - ) + (async_drop_in_place_fn_def_id, tcx.mk_args(&[ty.into()])) } else { // `drop_in_place` in place does not exist, don't try // to use it. @@ -480,6 +477,17 @@ fn upstream_drop_glue_for_provider<'tcx>( } } +fn upstream_async_drop_glue_for_provider<'tcx>( + tcx: TyCtxt<'tcx>, + args: GenericArgsRef<'tcx>, +) -> Option { + if let Some(def_id) = tcx.lang_items().async_drop_in_place_fn() { + tcx.upstream_monomorphizations_for(def_id).and_then(|monos| monos.get(&args).cloned()) + } else { + None + } +} + fn is_unreachable_local_definition_provider(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool { !tcx.reachable_set(()).contains(&def_id) } @@ -491,6 +499,7 @@ pub fn provide(providers: &mut Providers) { providers.upstream_monomorphizations = upstream_monomorphizations_provider; providers.is_unreachable_local_definition = is_unreachable_local_definition_provider; providers.upstream_drop_glue_for = upstream_drop_glue_for_provider; + providers.upstream_async_drop_glue_for = upstream_async_drop_glue_for_provider; providers.wasm_import_module_map = wasm_import_module_map; providers.extern_queries.is_reachable_non_generic = is_reachable_non_generic_provider_extern; providers.extern_queries.upstream_monomorphizations_for = diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs index 0f08694c4eabd..c5afecffb07af 100644 --- a/compiler/rustc_middle/src/query/mod.rs +++ b/compiler/rustc_middle/src/query/mod.rs @@ -1554,12 +1554,13 @@ rustc_queries! { } } - /// The entire set of monomorphizations the local crate can safely link - /// to because they are exported from upstream crates. Do not depend on - /// this directly, as its value changes anytime a monomorphization gets - /// added or removed in any upstream crate. Instead use the narrower - /// `upstream_monomorphizations_for`, `upstream_drop_glue_for`, or, even - /// better, `Instance::upstream_monomorphization()`. + /// The entire set of monomorphizations the local crate can safely + /// link to because they are exported from upstream crates. Do + /// not depend on this directly, as its value changes anytime + /// a monomorphization gets added or removed in any upstream + /// crate. Instead use the narrower `upstream_monomorphizations_for`, + /// `upstream_drop_glue_for`, `upstream_async_drop_glue_for`, or, + /// even better, `Instance::upstream_monomorphization()`. query upstream_monomorphizations(_: ()) -> &'tcx DefIdMap, CrateNum>> { arena_cache desc { "collecting available upstream monomorphizations" } @@ -1601,6 +1602,26 @@ rustc_queries! { desc { "available upstream drop-glue for `{:?}`", args } } + /// Returns the upstream crate that exports async-drop-glue for + /// the given type (`args` is expected to be a single-item list + /// containing the type one wants async-drop-glue for). + /// + /// This is a subset of `upstream_monomorphizations_for` in order + /// to increase dep-tracking granularity. Otherwise adding or + /// removing any type with async-drop-glue in any upstream crate + /// would invalidate all functions calling async-drop-glue of an + /// upstream type. + /// + /// You likely want to call `Instance::upstream_monomorphization()` + /// instead of invoking this query directly. + /// + /// NOTE: This query could easily be extended to also support other + /// common functions that have are large set of monomorphizations + /// (like `Clone::clone` for example). + query upstream_async_drop_glue_for(args: GenericArgsRef<'tcx>) -> Option { + desc { "available upstream async-drop-glue for `{:?}`", args } + } + /// Returns a list of all `extern` blocks of a crate. query foreign_modules(_: CrateNum) -> &'tcx FxIndexMap { arena_cache diff --git a/compiler/rustc_middle/src/ty/instance.rs b/compiler/rustc_middle/src/ty/instance.rs index 5718264c94466..099b14cca9ce2 100644 --- a/compiler/rustc_middle/src/ty/instance.rs +++ b/compiler/rustc_middle/src/ty/instance.rs @@ -219,8 +219,9 @@ impl<'tcx> Instance<'tcx> { InstanceKind::Item(def) => tcx .upstream_monomorphizations_for(def) .and_then(|monos| monos.get(&self.args).cloned()), - InstanceKind::DropGlue(_, Some(_)) | InstanceKind::AsyncDropGlueCtorShim(_, _) => { - tcx.upstream_drop_glue_for(self.args) + InstanceKind::DropGlue(_, Some(_)) => tcx.upstream_drop_glue_for(self.args), + InstanceKind::AsyncDropGlueCtorShim(_, Some(_)) => { + tcx.upstream_async_drop_glue_for(self.args) } _ => None, } @@ -256,7 +257,7 @@ impl<'tcx> InstanceKind<'tcx> { match self { ty::InstanceKind::Item(def) => Some(def), ty::InstanceKind::DropGlue(def_id, Some(_)) - | InstanceKind::AsyncDropGlueCtorShim(def_id, _) + | InstanceKind::AsyncDropGlueCtorShim(def_id, Some(_)) | InstanceKind::ThreadLocalShim(def_id) => Some(def_id), InstanceKind::VTableShim(..) | InstanceKind::ReifyShim(..) @@ -267,6 +268,7 @@ impl<'tcx> InstanceKind<'tcx> { | ty::InstanceKind::ConstructCoroutineInClosureShim { .. } | ty::InstanceKind::CoroutineKindShim { .. } | InstanceKind::DropGlue(..) + | InstanceKind::AsyncDropGlueCtorShim(..) | InstanceKind::CloneShim(..) | InstanceKind::FnPtrAddrShim(..) => None, } @@ -332,6 +334,26 @@ impl<'tcx> InstanceKind<'tcx> { .map_or_else(|| adt_def.is_enum(), |dtor| tcx.cross_crate_inlinable(dtor.did)) }); } + if let ty::InstanceKind::AsyncDropGlueCtorShim(.., Some(ty)) = *self { + // Async drop glue generally wants to be instantiated at + // every codegen unit, but without an #[inline] hint. We + // should make this available to normal end-users. + if tcx.sess.opts.incremental.is_none() { + return true; + } + // When compiling with incremental, we can generate a *lot* of + // codegen units. Including drop glue into all of them has a + // considerable compile time cost. + // + // We include enums without destructors to allow, say, optimizing + // drops of `Option::None` before LTO. We also respect the intent of + // `#[inline]` on `Drop::drop` implementations. + return ty.ty_adt_def().map_or(true, |adt_def| { + adt_def + .async_destructor(tcx) + .map_or_else(|| adt_def.is_enum(), |dtor| tcx.cross_crate_inlinable(dtor.ctor)) + }); + } if let ty::InstanceKind::ThreadLocalShim(..) = *self { return false; } diff --git a/compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs b/compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs index 832efb1199926..742ec4c377ccf 100644 --- a/compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs +++ b/compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs @@ -288,6 +288,7 @@ pub fn transform_instance<'tcx>( mut instance: Instance<'tcx>, options: TransformTyOptions, ) -> Instance<'tcx> { + // FIXME: account for async-drop-glue if (matches!(instance.def, ty::InstanceKind::Virtual(..)) && tcx.is_lang_item(instance.def_id(), LangItem::DropInPlace)) || matches!(instance.def, ty::InstanceKind::DropGlue(..)) From 1a8eae1aba998af1b0fdc597c0e263d4d391b169 Mon Sep 17 00:00:00 2001 From: Daria Sukhonina Date: Tue, 18 Jun 2024 14:28:00 +0300 Subject: [PATCH 2/2] Apply suggestions from oli-obk's review Co-authored-by: Oli Scherer --- .../src/back/symbol_export.rs | 14 +++----- compiler/rustc_middle/src/ty/instance.rs | 35 ++++++------------- 2 files changed, 15 insertions(+), 34 deletions(-) diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs index c868904c5511c..6abe4fa1c3809 100644 --- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs +++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs @@ -470,22 +470,16 @@ fn upstream_drop_glue_for_provider<'tcx>( tcx: TyCtxt<'tcx>, args: GenericArgsRef<'tcx>, ) -> Option { - if let Some(def_id) = tcx.lang_items().drop_in_place_fn() { - tcx.upstream_monomorphizations_for(def_id).and_then(|monos| monos.get(&args).cloned()) - } else { - None - } + let def_id = tcx.lang_items().drop_in_place_fn()?; + tcx.upstream_monomorphizations_for(def_id)?.get(&args).cloned() } fn upstream_async_drop_glue_for_provider<'tcx>( tcx: TyCtxt<'tcx>, args: GenericArgsRef<'tcx>, ) -> Option { - if let Some(def_id) = tcx.lang_items().async_drop_in_place_fn() { - tcx.upstream_monomorphizations_for(def_id).and_then(|monos| monos.get(&args).cloned()) - } else { - None - } + let def_id = tcx.lang_items().async_drop_in_place_fn()?; + tcx.upstream_monomorphizations_for(def_id)?.get(&args).cloned() } fn is_unreachable_local_definition_provider(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool { diff --git a/compiler/rustc_middle/src/ty/instance.rs b/compiler/rustc_middle/src/ty/instance.rs index 099b14cca9ce2..efaf9c7231bb4 100644 --- a/compiler/rustc_middle/src/ty/instance.rs +++ b/compiler/rustc_middle/src/ty/instance.rs @@ -314,7 +314,9 @@ impl<'tcx> InstanceKind<'tcx> { if self.requires_inline(tcx) { return true; } - if let ty::InstanceKind::DropGlue(.., Some(ty)) = *self { + if let ty::InstanceKind::DropGlue(.., Some(ty)) + | ty::InstanceKind::AsyncDropGlueCtorShim(.., Some(ty)) = *self + { // Drop glue generally wants to be instantiated at every codegen // unit, but without an #[inline] hint. We should make this // available to normal end-users. @@ -329,29 +331,14 @@ impl<'tcx> InstanceKind<'tcx> { // drops of `Option::None` before LTO. We also respect the intent of // `#[inline]` on `Drop::drop` implementations. return ty.ty_adt_def().map_or(true, |adt_def| { - adt_def - .destructor(tcx) - .map_or_else(|| adt_def.is_enum(), |dtor| tcx.cross_crate_inlinable(dtor.did)) - }); - } - if let ty::InstanceKind::AsyncDropGlueCtorShim(.., Some(ty)) = *self { - // Async drop glue generally wants to be instantiated at - // every codegen unit, but without an #[inline] hint. We - // should make this available to normal end-users. - if tcx.sess.opts.incremental.is_none() { - return true; - } - // When compiling with incremental, we can generate a *lot* of - // codegen units. Including drop glue into all of them has a - // considerable compile time cost. - // - // We include enums without destructors to allow, say, optimizing - // drops of `Option::None` before LTO. We also respect the intent of - // `#[inline]` on `Drop::drop` implementations. - return ty.ty_adt_def().map_or(true, |adt_def| { - adt_def - .async_destructor(tcx) - .map_or_else(|| adt_def.is_enum(), |dtor| tcx.cross_crate_inlinable(dtor.ctor)) + match *self { + ty::InstanceKind::DropGlue(..) => adt_def.destructor(tcx).map(|dtor| dtor.did), + ty::InstanceKind::AsyncDropGlueCtorShim(..) => { + adt_def.async_destructor(tcx).map(|dtor| dtor.ctor) + } + _ => unreachable!(), + } + .map_or_else(|| adt_def.is_enum(), |did| tcx.cross_crate_inlinable(did)) }); } if let ty::InstanceKind::ThreadLocalShim(..) = *self {