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21 changes: 12 additions & 9 deletions compiler/rustc_ast_lowering/src/expr.rs
Original file line number Diff line number Diff line change
Expand Up @@ -524,15 +524,15 @@ impl<'hir> LoweringContext<'_, 'hir> {
this.mark_span_with_reason(
DesugaringKind::TryBlock,
expr.span,
this.allow_try_trait.clone(),
Some(this.allow_try_trait.clone()),
),
expr,
)
} else {
let try_span = this.mark_span_with_reason(
DesugaringKind::TryBlock,
this.tcx.sess.source_map().end_point(body.span),
this.allow_try_trait.clone(),
Some(this.allow_try_trait.clone()),
);

(try_span, this.expr_unit(try_span))
Expand Down Expand Up @@ -612,8 +612,11 @@ impl<'hir> LoweringContext<'_, 'hir> {
let output = ret_ty.unwrap_or_else(|| hir::FnRetTy::DefaultReturn(self.lower_span(span)));

// Resume argument type: `ResumeTy`
let unstable_span =
self.mark_span_with_reason(DesugaringKind::Async, span, self.allow_gen_future.clone());
let unstable_span = self.mark_span_with_reason(
DesugaringKind::Async,
span,
Some(self.allow_gen_future.clone()),
);
let resume_ty = hir::QPath::LangItem(hir::LangItem::ResumeTy, unstable_span);
let input_ty = hir::Ty {
hir_id: self.next_id(),
Expand Down Expand Up @@ -735,7 +738,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
let unstable_span = self.mark_span_with_reason(
DesugaringKind::Async,
span,
self.allow_gen_future.clone(),
Some(self.allow_gen_future.clone()),
);
self.lower_attrs(
inner_hir_id,
Expand Down Expand Up @@ -782,7 +785,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
let gen_future_span = self.mark_span_with_reason(
DesugaringKind::Await,
full_span,
self.allow_gen_future.clone(),
Some(self.allow_gen_future.clone()),
);
let expr = self.lower_expr_mut(expr);
let expr_hir_id = expr.hir_id;
Expand Down Expand Up @@ -1640,13 +1643,13 @@ impl<'hir> LoweringContext<'_, 'hir> {
let unstable_span = self.mark_span_with_reason(
DesugaringKind::QuestionMark,
span,
self.allow_try_trait.clone(),
Some(self.allow_try_trait.clone()),
);
let try_span = self.tcx.sess.source_map().end_point(span);
let try_span = self.mark_span_with_reason(
DesugaringKind::QuestionMark,
try_span,
self.allow_try_trait.clone(),
Some(self.allow_try_trait.clone()),
);

// `Try::branch(<expr>)`
Expand Down Expand Up @@ -1739,7 +1742,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
let unstable_span = self.mark_span_with_reason(
DesugaringKind::YeetExpr,
span,
self.allow_try_trait.clone(),
Some(self.allow_try_trait.clone()),
);

let from_yeet_expr = self.wrap_in_try_constructor(
Expand Down
2 changes: 1 addition & 1 deletion compiler/rustc_ast_lowering/src/index.rs
Original file line number Diff line number Diff line change
Expand Up @@ -10,7 +10,7 @@ use rustc_middle::ty::TyCtxt;
use rustc_span::{Span, DUMMY_SP};

/// A visitor that walks over the HIR and collects `Node`s into a HIR map.
pub(super) struct NodeCollector<'a, 'hir> {
struct NodeCollector<'a, 'hir> {
tcx: TyCtxt<'hir>,

bodies: &'a SortedMap<ItemLocalId, &'hir Body<'hir>>,
Expand Down
106 changes: 38 additions & 68 deletions compiler/rustc_ast_lowering/src/item.rs
Original file line number Diff line number Diff line change
Expand Up @@ -7,7 +7,6 @@ use hir::definitions::DefPathData;
use rustc_ast::ptr::P;
use rustc_ast::visit::AssocCtxt;
use rustc_ast::*;
use rustc_data_structures::sorted_map::SortedMap;
use rustc_errors::ErrorGuaranteed;
use rustc_hir as hir;
use rustc_hir::def::{DefKind, Res};
Expand Down Expand Up @@ -55,42 +54,7 @@ impl<'a, 'hir> ItemLowerer<'a, 'hir> {
owner: NodeId,
f: impl FnOnce(&mut LoweringContext<'_, 'hir>) -> hir::OwnerNode<'hir>,
) {
let allow_gen_future = Some(if self.tcx.features().async_fn_track_caller {
[sym::gen_future, sym::closure_track_caller][..].into()
} else {
[sym::gen_future][..].into()
});
let mut lctx = LoweringContext {
// Pseudo-globals.
tcx: self.tcx,
resolver: self.resolver,
arena: self.tcx.hir_arena,

// HirId handling.
bodies: Vec::new(),
attrs: SortedMap::default(),
children: Vec::default(),
current_hir_id_owner: hir::CRATE_OWNER_ID,
item_local_id_counter: hir::ItemLocalId::new(0),
node_id_to_local_id: Default::default(),
trait_map: Default::default(),

// Lowering state.
catch_scope: None,
loop_scope: None,
is_in_loop_condition: false,
is_in_trait_impl: false,
is_in_dyn_type: false,
coroutine_kind: None,
task_context: None,
current_item: None,
impl_trait_defs: Vec::new(),
impl_trait_bounds: Vec::new(),
allow_try_trait: Some([sym::try_trait_v2, sym::yeet_desugar_details][..].into()),
allow_gen_future,
generics_def_id_map: Default::default(),
host_param_id: None,
};
let mut lctx = LoweringContext::new(self.tcx, self.resolver);
lctx.with_hir_id_owner(owner, |lctx| f(lctx));

for (def_id, info) in lctx.children {
Expand Down Expand Up @@ -136,39 +100,9 @@ impl<'a, 'hir> ItemLowerer<'a, 'hir> {

fn lower_assoc_item(&mut self, item: &AssocItem, ctxt: AssocCtxt) {
let def_id = self.resolver.node_id_to_def_id[&item.id];

let parent_id = self.tcx.local_parent(def_id);
let parent_hir = self.lower_node(parent_id).unwrap();
self.with_lctx(item.id, |lctx| {
// Evaluate with the lifetimes in `params` in-scope.
// This is used to track which lifetimes have already been defined,
// and which need to be replicated when lowering an async fn.

match parent_hir.node().expect_item().kind {
hir::ItemKind::Impl(impl_) => {
lctx.is_in_trait_impl = impl_.of_trait.is_some();
}
hir::ItemKind::Trait(_, _, generics, _, _) if lctx.tcx.features().effects => {
lctx.host_param_id = generics
.params
.iter()
.find(|param| {
parent_hir
.attrs
.get(param.hir_id.local_id)
.iter()
.any(|attr| attr.has_name(sym::rustc_host))
})
.map(|param| param.def_id);
}
_ => {}
}

match ctxt {
AssocCtxt::Trait => hir::OwnerNode::TraitItem(lctx.lower_trait_item(item)),
AssocCtxt::Impl => hir::OwnerNode::ImplItem(lctx.lower_impl_item(item)),
}
})
self.with_lctx(item.id, |lctx| lctx.lower_assoc_item(item, ctxt, parent_hir))
}

fn lower_foreign_item(&mut self, item: &ForeignItem) {
Expand Down Expand Up @@ -609,6 +543,42 @@ impl<'hir> LoweringContext<'_, 'hir> {
}
}

fn lower_assoc_item(
&mut self,
item: &AssocItem,
ctxt: AssocCtxt,
parent_hir: &'hir hir::OwnerInfo<'hir>,
) -> hir::OwnerNode<'hir> {
// Evaluate with the lifetimes in `params` in-scope.
// This is used to track which lifetimes have already been defined,
// and which need to be replicated when lowering an async fn.

match parent_hir.node().expect_item().kind {
hir::ItemKind::Impl(impl_) => {
self.is_in_trait_impl = impl_.of_trait.is_some();
}
hir::ItemKind::Trait(_, _, generics, _, _) if self.tcx.features().effects => {
self.host_param_id = generics
.params
.iter()
.find(|param| {
parent_hir
.attrs
.get(param.hir_id.local_id)
.iter()
.any(|attr| attr.has_name(sym::rustc_host))
})
.map(|param| param.def_id);
}
_ => {}
}

match ctxt {
AssocCtxt::Trait => hir::OwnerNode::TraitItem(self.lower_trait_item(item)),
AssocCtxt::Impl => hir::OwnerNode::ImplItem(self.lower_impl_item(item)),
}
}

fn lower_foreign_item(&mut self, i: &ForeignItem) -> &'hir hir::ForeignItem<'hir> {
let hir_id = self.lower_node_id(i.id);
let owner_id = hir_id.expect_owner();
Expand Down
45 changes: 42 additions & 3 deletions compiler/rustc_ast_lowering/src/lib.rs
Original file line number Diff line number Diff line change
Expand Up @@ -35,7 +35,6 @@
#![doc(rust_logo)]
#![feature(box_patterns)]
#![feature(let_chains)]
#![feature(never_type)]
#![recursion_limit = "256"]
#![deny(rustc::untranslatable_diagnostic)]
#![deny(rustc::diagnostic_outside_of_impl)]
Expand Down Expand Up @@ -133,8 +132,8 @@ struct LoweringContext<'a, 'hir> {
/// NodeIds that are lowered inside the current HIR owner.
node_id_to_local_id: FxHashMap<NodeId, hir::ItemLocalId>,

allow_try_trait: Option<Lrc<[Symbol]>>,
allow_gen_future: Option<Lrc<[Symbol]>>,
allow_try_trait: Lrc<[Symbol]>,
allow_gen_future: Lrc<[Symbol]>,

/// Mapping from generics `def_id`s to TAIT generics `def_id`s.
/// For each captured lifetime (e.g., 'a), we create a new lifetime parameter that is a generic
Expand All @@ -145,6 +144,46 @@ struct LoweringContext<'a, 'hir> {
host_param_id: Option<LocalDefId>,
}

impl<'a, 'hir> LoweringContext<'a, 'hir> {
fn new(tcx: TyCtxt<'hir>, resolver: &'a mut ResolverAstLowering) -> Self {
Self {
// Pseudo-globals.
tcx,
resolver: resolver,
arena: tcx.hir_arena,

// HirId handling.
bodies: Vec::new(),
attrs: SortedMap::default(),
children: Vec::default(),
current_hir_id_owner: hir::CRATE_OWNER_ID,
item_local_id_counter: hir::ItemLocalId::new(0),
node_id_to_local_id: Default::default(),
trait_map: Default::default(),

// Lowering state.
catch_scope: None,
loop_scope: None,
is_in_loop_condition: false,
is_in_trait_impl: false,
is_in_dyn_type: false,
coroutine_kind: None,
task_context: None,
current_item: None,
impl_trait_defs: Vec::new(),
impl_trait_bounds: Vec::new(),
allow_try_trait: [sym::try_trait_v2, sym::yeet_desugar_details].into(),
allow_gen_future: if tcx.features().async_fn_track_caller {
[sym::gen_future, sym::closure_track_caller].into()
} else {
[sym::gen_future].into()
},
generics_def_id_map: Default::default(),
host_param_id: None,
}
}
}

trait ResolverAstLoweringExt {
fn legacy_const_generic_args(&self, expr: &Expr) -> Option<Vec<usize>>;
fn get_partial_res(&self, id: NodeId) -> Option<PartialRes>;
Expand Down
2 changes: 1 addition & 1 deletion compiler/rustc_ast_lowering/src/lifetime_collector.rs
Original file line number Diff line number Diff line change
Expand Up @@ -108,7 +108,7 @@ impl<'ast> Visitor<'ast> for LifetimeCollectVisitor<'ast> {
}
}

pub fn lifetimes_in_bounds(
pub(crate) fn lifetimes_in_bounds(
resolver: &ResolverAstLowering,
bounds: &GenericBounds,
) -> Vec<Lifetime> {
Expand Down
2 changes: 1 addition & 1 deletion compiler/rustc_ast_lowering/src/pat.rs
Original file line number Diff line number Diff line change
Expand Up @@ -18,7 +18,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
self.arena.alloc(self.lower_pat_mut(pattern))
}

pub(crate) fn lower_pat_mut(&mut self, mut pattern: &Pat) -> hir::Pat<'hir> {
fn lower_pat_mut(&mut self, mut pattern: &Pat) -> hir::Pat<'hir> {
ensure_sufficient_stack(|| {
// loop here to avoid recursion
let node = loop {
Expand Down
2 changes: 1 addition & 1 deletion compiler/rustc_data_structures/src/graph/scc/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -492,7 +492,7 @@ where
let returned_walk =
return_value.take().into_iter().map(|walk| (*successor_node, Some(walk)));

let successor_walk = successors.by_ref().map(|successor_node| {
let successor_walk = successors.map(|successor_node| {
debug!(?node, ?successor_node);
(successor_node, self.inspect_node(successor_node))
});
Expand Down
1 change: 0 additions & 1 deletion compiler/rustc_span/src/def_id.rs
Original file line number Diff line number Diff line change
Expand Up @@ -222,7 +222,6 @@ rustc_index::newtype_index! {
}
}

// njn: I don't understand these
impl<E: Encoder> Encodable<E> for DefIndex {
default fn encode(&self, _: &mut E) {
panic!("cannot encode `DefIndex` with `{}`", std::any::type_name::<E>());
Expand Down