diff options
Diffstat (limited to 'compiler/rustc_ast_lowering/src/lib.rs')
| -rw-r--r-- | compiler/rustc_ast_lowering/src/lib.rs | 105 |
1 files changed, 90 insertions, 15 deletions
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs index d29e9f9b3f6..89775bdee26 100644 --- a/compiler/rustc_ast_lowering/src/lib.rs +++ b/compiler/rustc_ast_lowering/src/lib.rs @@ -142,6 +142,8 @@ struct LoweringContext<'a, 'hir> { /// defined on the TAIT, so we have type Foo<'a1> = ... and we establish a mapping in this /// field from the original parameter 'a to the new parameter 'a1. generics_def_id_map: Vec<FxHashMap<LocalDefId, LocalDefId>>, + + host_param_id: Option<LocalDefId>, } trait ResolverAstLoweringExt { @@ -455,7 +457,7 @@ pub fn lower_to_hir(tcx: TyCtxt<'_>, (): ()) -> hir::Crate<'_> { // Don't hash unless necessary, because it's expensive. let opt_hir_hash = - if tcx.sess.needs_crate_hash() { Some(compute_hir_hash(tcx, &owners)) } else { None }; + if tcx.needs_crate_hash() { Some(compute_hir_hash(tcx, &owners)) } else { None }; hir::Crate { owners, opt_hir_hash } } @@ -646,7 +648,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { let bodies = SortedMap::from_presorted_elements(bodies); // Don't hash unless necessary, because it's expensive. - let (opt_hash_including_bodies, attrs_hash) = if self.tcx.sess.needs_crate_hash() { + let (opt_hash_including_bodies, attrs_hash) = if self.tcx.needs_crate_hash() { self.tcx.with_stable_hashing_context(|mut hcx| { let mut stable_hasher = StableHasher::new(); hcx.with_hir_bodies(node.def_id(), &bodies, |hcx| { @@ -1262,6 +1264,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { span: t.span }, itctx, + ast::Const::No, ); let bounds = this.arena.alloc_from_iter([bound]); let lifetime_bound = this.elided_dyn_bound(t.span); @@ -1272,7 +1275,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { } let id = self.lower_node_id(t.id); - let qpath = self.lower_qpath(t.id, qself, path, param_mode, itctx); + let qpath = self.lower_qpath(t.id, qself, path, param_mode, itctx, None); self.ty_path(id, t.span, qpath) } @@ -1356,10 +1359,12 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { this.arena.alloc_from_iter(bounds.iter().filter_map(|bound| match bound { GenericBound::Trait( ty, - TraitBoundModifier::None + modifier @ (TraitBoundModifier::None | TraitBoundModifier::MaybeConst - | TraitBoundModifier::Negative, - ) => Some(this.lower_poly_trait_ref(ty, itctx)), + | TraitBoundModifier::Negative), + ) => { + Some(this.lower_poly_trait_ref(ty, itctx, modifier.to_constness())) + } // `~const ?Bound` will cause an error during AST validation // anyways, so treat it like `?Bound` as compilation proceeds. GenericBound::Trait( @@ -1663,11 +1668,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { ); debug!("lower_async_fn_ret_ty: generic_params={:#?}", generic_params); - let lifetime_mapping = if in_trait { - Some(&*self.arena.alloc_slice(&synthesized_lifetime_args)) - } else { - None - }; + let lifetime_mapping = self.arena.alloc_slice(&synthesized_lifetime_args); let opaque_ty_item = hir::OpaqueTy { generics: this.arena.alloc(hir::Generics { @@ -1956,7 +1957,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { ) -> hir::GenericBound<'hir> { match tpb { GenericBound::Trait(p, modifier) => hir::GenericBound::Trait( - self.lower_poly_trait_ref(p, itctx), + self.lower_poly_trait_ref(p, itctx, modifier.to_constness()), self.lower_trait_bound_modifier(*modifier), ), GenericBound::Outlives(lifetime) => { @@ -2099,8 +2100,20 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { } } - fn lower_trait_ref(&mut self, p: &TraitRef, itctx: &ImplTraitContext) -> hir::TraitRef<'hir> { - let path = match self.lower_qpath(p.ref_id, &None, &p.path, ParamMode::Explicit, itctx) { + fn lower_trait_ref( + &mut self, + constness: ast::Const, + p: &TraitRef, + itctx: &ImplTraitContext, + ) -> hir::TraitRef<'hir> { + let path = match self.lower_qpath( + p.ref_id, + &None, + &p.path, + ParamMode::Explicit, + itctx, + Some(constness), + ) { hir::QPath::Resolved(None, path) => path, qpath => panic!("lower_trait_ref: unexpected QPath `{qpath:?}`"), }; @@ -2112,10 +2125,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { &mut self, p: &PolyTraitRef, itctx: &ImplTraitContext, + constness: ast::Const, ) -> hir::PolyTraitRef<'hir> { let bound_generic_params = self.lower_lifetime_binder(p.trait_ref.ref_id, &p.bound_generic_params); - let trait_ref = self.lower_trait_ref(&p.trait_ref, itctx); + let trait_ref = self.lower_trait_ref(constness, &p.trait_ref, itctx); hir::PolyTraitRef { bound_generic_params, trait_ref, span: self.lower_span(p.span) } } @@ -2469,6 +2483,67 @@ struct GenericArgsCtor<'hir> { } impl<'hir> GenericArgsCtor<'hir> { + fn push_constness(&mut self, lcx: &mut LoweringContext<'_, 'hir>, constness: ast::Const) { + if !lcx.tcx.features().effects { + return; + } + + // if bound is non-const, don't add host effect param + let ast::Const::Yes(span) = constness else { return }; + + let span = lcx.lower_span(span); + + let id = lcx.next_node_id(); + let hir_id = lcx.next_id(); + let body = lcx.lower_body(|lcx| { + ( + &[], + match constness { + ast::Const::Yes(_) => { + let hir_id = lcx.next_id(); + let res = + Res::Def(DefKind::ConstParam, lcx.host_param_id.unwrap().to_def_id()); + let expr_kind = hir::ExprKind::Path(hir::QPath::Resolved( + None, + lcx.arena.alloc(hir::Path { + span, + res, + segments: arena_vec![lcx; hir::PathSegment::new(Ident { + name: sym::host, + span, + }, hir_id, res)], + }), + )); + lcx.expr(span, expr_kind) + } + ast::Const::No => lcx.expr( + span, + hir::ExprKind::Lit( + lcx.arena.alloc(hir::Lit { span, node: ast::LitKind::Bool(true) }), + ), + ), + }, + ) + }); + + let attr_id = lcx.tcx.sess.parse_sess.attr_id_generator.mk_attr_id(); + let attr = lcx.arena.alloc(Attribute { + kind: AttrKind::Normal(P(NormalAttr::from_ident(Ident::new(sym::rustc_host, span)))), + span, + id: attr_id, + style: AttrStyle::Outer, + }); + lcx.attrs.insert(hir_id.local_id, std::slice::from_ref(attr)); + + let def_id = + lcx.create_def(lcx.current_hir_id_owner.def_id, id, DefPathData::AnonConst, span); + lcx.children.push((def_id, hir::MaybeOwner::NonOwner(hir_id))); + self.args.push(hir::GenericArg::Const(hir::ConstArg { + value: hir::AnonConst { def_id, hir_id, body }, + span, + })) + } + fn is_empty(&self) -> bool { self.args.is_empty() && self.bindings.is_empty() |