Skip to content

Commit 8ca44ef

Browse files
borsbors
committed
Auto merge of #112988 - spastorino:new-rpitit-24, r=compiler-errors
 Replace RPITIT current impl with new strategy that lowers as a GAT This PR replaces the current implementation of RPITITs with the new implementation that we had under -Zlower-impl-trait-in-trait-to-assoc-ty flag that lowers the RPIT as a GAT on the trait and on the impls that implement that trait. Opening this PR as a draft because this goes after #112682, ~#112981~ and ~#112983~. As soon as those are merged, I can rebase and we should run perf, crater and test a lot. r? `@compiler-errors`
2 parents 05b82e5 + 20429af commit 8ca44ef

File tree

146 files changed

+1106
-586
lines changed

Some content is hidden

Large Commits have some content hidden by default. Use the searchbox below for content that may be hidden.

146 files changed

+1106
-586
lines changed

‎compiler/rustc_hir/src/def.rs

+1-6
Original file line numberDiff line numberDiff line change
@@ -109,8 +109,6 @@ pub enum DefKind {
109109
InlineConst,
110110
/// Opaque type, aka `impl Trait`.
111111
OpaqueTy,
112-
/// A return-position `impl Trait` in a trait definition
113-
ImplTraitPlaceholder,
114112
Field,
115113
/// Lifetime parameter: the `'a` in `struct Foo<'a> { ... }`
116114
LifetimeParam,
@@ -143,7 +141,6 @@ impl DefKind {
143141
DefKind::Ctor(CtorOf::Struct, CtorKind::Fn) => "tuple struct",
144142
DefKind::Ctor(CtorOf::Struct, CtorKind::Const) => "unit struct",
145143
DefKind::OpaqueTy => "opaque type",
146-
DefKind::ImplTraitPlaceholder => "opaque type in trait",
147144
DefKind::TyAlias => "type alias",
148145
DefKind::TraitAlias => "trait alias",
149146
DefKind::AssocTy => "associated type",
@@ -227,8 +224,7 @@ impl DefKind {
227224
| DefKind::Use
228225
| DefKind::ForeignMod
229226
| DefKind::GlobalAsm
230-
| DefKind::Impl { .. }
231-
| DefKind::ImplTraitPlaceholder => None,
227+
| DefKind::Impl { .. } => None,
232228
}
233229
}
234230

@@ -262,7 +258,6 @@ impl DefKind {
262258
| DefKind::Use
263259
| DefKind::ForeignMod
264260
| DefKind::OpaqueTy
265-
| DefKind::ImplTraitPlaceholder
266261
| DefKind::Impl { .. }
267262
| DefKind::Field
268263
| DefKind::TyParam

‎compiler/rustc_hir/src/target.rs

+1-10
Original file line numberDiff line numberDiff line change
@@ -36,7 +36,6 @@ pub enum Target {
3636
GlobalAsm,
3737
TyAlias,
3838
OpaqueTy,
39-
ImplTraitPlaceholder,
4039
Enum,
4140
Variant,
4241
Struct,
@@ -80,13 +79,7 @@ impl Target {
8079
ItemKind::ForeignMod { .. } => Target::ForeignMod,
8180
ItemKind::GlobalAsm(..) => Target::GlobalAsm,
8281
ItemKind::TyAlias(..) => Target::TyAlias,
83-
ItemKind::OpaqueTy(ref opaque) => {
84-
if opaque.in_trait {
85-
Target::ImplTraitPlaceholder
86-
} else {
87-
Target::OpaqueTy
88-
}
89-
}
82+
ItemKind::OpaqueTy(..) => Target::OpaqueTy,
9083
ItemKind::Enum(..) => Target::Enum,
9184
ItemKind::Struct(..) => Target::Struct,
9285
ItemKind::Union(..) => Target::Union,
@@ -110,7 +103,6 @@ impl Target {
110103
DefKind::GlobalAsm => Target::GlobalAsm,
111104
DefKind::TyAlias => Target::TyAlias,
112105
DefKind::OpaqueTy => Target::OpaqueTy,
113-
DefKind::ImplTraitPlaceholder => Target::ImplTraitPlaceholder,
114106
DefKind::Enum => Target::Enum,
115107
DefKind::Struct => Target::Struct,
116108
DefKind::Union => Target::Union,
@@ -165,7 +157,6 @@ impl Target {
165157
Target::GlobalAsm => "global asm",
166158
Target::TyAlias => "type alias",
167159
Target::OpaqueTy => "opaque type",
168-
Target::ImplTraitPlaceholder => "opaque type in trait",
169160
Target::Enum => "enum",
170161
Target::Variant => "enum variant",
171162
Target::Struct => "struct",

‎compiler/rustc_hir_analysis/src/astconv/mod.rs

+2-2
Original file line numberDiff line numberDiff line change
@@ -2128,7 +2128,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
21282128

21292129
let span = path.span;
21302130
match path.res {
2131-
Res::Def(DefKind::OpaqueTy | DefKind::ImplTraitPlaceholder, did) => {
2131+
Res::Def(DefKind::OpaqueTy, did) => {
21322132
// Check for desugared `impl Trait`.
21332133
assert!(tcx.is_type_alias_impl_trait(did));
21342134
let item_segment = path.segments.split_last().unwrap();
@@ -2439,7 +2439,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
24392439
// If this is an RPITIT and we are using the new RPITIT lowering scheme, we
24402440
// generate the def_id of an associated type for the trait and return as
24412441
// type a projection.
2442-
let def_id = if in_trait && tcx.lower_impl_trait_in_trait_to_assoc_ty() {
2442+
let def_id = if in_trait {
24432443
tcx.associated_type_for_impl_trait_in_trait(local_def_id).to_def_id()
24442444
} else {
24452445
local_def_id.to_def_id()

‎compiler/rustc_hir_analysis/src/check/check.rs

+1-17
Original file line numberDiff line numberDiff line change
@@ -302,16 +302,11 @@ pub(super) fn check_opaque_for_inheriting_lifetimes(
302302

303303
if let ItemKind::OpaqueTy(&hir::OpaqueTy {
304304
origin: hir::OpaqueTyOrigin::AsyncFn(..) | hir::OpaqueTyOrigin::FnReturn(..),
305-
in_trait,
306305
..
307306
}) = item.kind
308307
{
309308
let substs = InternalSubsts::identity_for_item(tcx, def_id);
310-
let opaque_identity_ty = if in_trait && !tcx.lower_impl_trait_in_trait_to_assoc_ty() {
311-
Ty::new_projection(tcx, def_id.to_def_id(), substs)
312-
} else {
313-
Ty::new_opaque(tcx, def_id.to_def_id(), substs)
314-
};
309+
let opaque_identity_ty = Ty::new_opaque(tcx, def_id.to_def_id(), substs);
315310
let mut visitor = ProhibitOpaqueVisitor {
316311
opaque_identity_ty,
317312
parent_count: tcx.generics_of(def_id).parent_count as u32,
@@ -576,17 +571,6 @@ fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
576571
check_opaque(tcx, id);
577572
}
578573
}
579-
DefKind::ImplTraitPlaceholder => {
580-
let parent = tcx.impl_trait_in_trait_parent_fn(id.owner_id.to_def_id());
581-
// Only check the validity of this opaque type if the function has a default body
582-
if let hir::Node::TraitItem(hir::TraitItem {
583-
kind: hir::TraitItemKind::Fn(_, hir::TraitFn::Provided(_)),
584-
..
585-
}) = tcx.hir().get_by_def_id(parent.expect_local())
586-
{
587-
check_opaque(tcx, id);
588-
}
589-
}
590574
DefKind::TyAlias => {
591575
let pty_ty = tcx.type_of(id.owner_id).subst_identity();
592576
let generics = tcx.generics_of(id.owner_id);

‎compiler/rustc_hir_analysis/src/collect/item_bounds.rs

+2-6
Original file line numberDiff line numberDiff line change
@@ -113,16 +113,12 @@ pub(super) fn explicit_item_bounds(
113113
..
114114
}) => associated_type_bounds(tcx, def_id, bounds, *span),
115115
hir::Node::Item(hir::Item {
116-
kind: hir::ItemKind::OpaqueTy(hir::OpaqueTy { bounds, in_trait, .. }),
116+
kind: hir::ItemKind::OpaqueTy(hir::OpaqueTy { bounds, .. }),
117117
span,
118118
..
119119
}) => {
120120
let substs = InternalSubsts::identity_for_item(tcx, def_id);
121-
let item_ty = if *in_trait && !tcx.lower_impl_trait_in_trait_to_assoc_ty() {
122-
Ty::new_projection(tcx, def_id.to_def_id(), substs)
123-
} else {
124-
Ty::new_opaque(tcx, def_id.to_def_id(), substs)
125-
};
121+
let item_ty = Ty::new_opaque(tcx, def_id.to_def_id(), substs);
126122
opaque_type_bounds(tcx, def_id, bounds, item_ty, *span)
127123
}
128124
hir::Node::Item(hir::Item { kind: hir::ItemKind::TyAlias(..), .. }) => &[],

‎compiler/rustc_hir_analysis/src/impl_wf_check.rs

+1-14
Original file line numberDiff line numberDiff line change
@@ -109,20 +109,7 @@ fn enforce_impl_params_are_constrained(tcx: TyCtxt<'_>, impl_def_id: LocalDefId)
109109
vec![]
110110
}
111111
}
112-
ty::AssocKind::Fn => {
113-
if !tcx.lower_impl_trait_in_trait_to_assoc_ty()
114-
&& item.defaultness(tcx).has_value()
115-
&& tcx.impl_method_has_trait_impl_trait_tys(item.def_id)
116-
&& let Ok(table) = tcx.collect_return_position_impl_trait_in_trait_tys(def_id)
117-
{
118-
table.values().copied().flat_map(|ty| {
119-
cgp::parameters_for(&ty.subst_identity(), true)
120-
}).collect()
121-
} else {
122-
vec![]
123-
}
124-
}
125-
ty::AssocKind::Const => vec![],
112+
ty::AssocKind::Fn | ty::AssocKind::Const => vec![],
126113
}
127114
})
128115
.collect();

‎compiler/rustc_hir_analysis/src/variance/mod.rs

+1-9
Original file line numberDiff line numberDiff line change
@@ -56,7 +56,7 @@ fn variances_of(tcx: TyCtxt<'_>, item_def_id: LocalDefId) -> &[ty::Variance] {
5656
let crate_map = tcx.crate_variances(());
5757
return crate_map.variances.get(&item_def_id.to_def_id()).copied().unwrap_or(&[]);
5858
}
59-
DefKind::OpaqueTy | DefKind::ImplTraitPlaceholder => {
59+
DefKind::OpaqueTy => {
6060
return variance_of_opaque(tcx, item_def_id);
6161
}
6262
_ => {}
@@ -115,14 +115,6 @@ fn variance_of_opaque(tcx: TyCtxt<'_>, item_def_id: LocalDefId) -> &[ty::Varianc
115115
{
116116
self.visit_opaque(*def_id, substs)
117117
}
118-
// FIXME(-Zlower-impl-trait-in-trait-to-assoc-ty) check whether this is necessary
119-
// at all for RPITITs.
120-
ty::Alias(_, ty::AliasTy { def_id, substs, .. })
121-
if self.tcx.is_impl_trait_in_trait(*def_id)
122-
&& !self.tcx.lower_impl_trait_in_trait_to_assoc_ty() =>
123-
{
124-
self.visit_opaque(*def_id, substs)
125-
}
126118
_ => t.super_visit_with(self),
127119
}
128120
}

‎compiler/rustc_metadata/src/rmeta/encoder.rs

+1-30
Original file line numberDiff line numberDiff line change
@@ -824,7 +824,6 @@ fn should_encode_span(def_kind: DefKind) -> bool {
824824
| DefKind::AnonConst
825825
| DefKind::InlineConst
826826
| DefKind::OpaqueTy
827-
| DefKind::ImplTraitPlaceholder
828827
| DefKind::Field
829828
| DefKind::Impl { .. }
830829
| DefKind::Closure
@@ -867,7 +866,6 @@ fn should_encode_attrs(def_kind: DefKind) -> bool {
867866
| DefKind::AnonConst
868867
| DefKind::InlineConst
869868
| DefKind::OpaqueTy
870-
| DefKind::ImplTraitPlaceholder
871869
| DefKind::LifetimeParam
872870
| DefKind::GlobalAsm
873871
| DefKind::Generator => false,
@@ -902,7 +900,6 @@ fn should_encode_expn_that_defined(def_kind: DefKind) -> bool {
902900
| DefKind::AnonConst
903901
| DefKind::InlineConst
904902
| DefKind::OpaqueTy
905-
| DefKind::ImplTraitPlaceholder
906903
| DefKind::Field
907904
| DefKind::LifetimeParam
908905
| DefKind::GlobalAsm
@@ -939,7 +936,6 @@ fn should_encode_visibility(def_kind: DefKind) -> bool {
939936
| DefKind::AnonConst
940937
| DefKind::InlineConst
941938
| DefKind::OpaqueTy
942-
| DefKind::ImplTraitPlaceholder
943939
| DefKind::GlobalAsm
944940
| DefKind::Impl { .. }
945941
| DefKind::Closure
@@ -966,7 +962,6 @@ fn should_encode_stability(def_kind: DefKind) -> bool {
966962
| DefKind::ForeignMod
967963
| DefKind::TyAlias
968964
| DefKind::OpaqueTy
969-
| DefKind::ImplTraitPlaceholder
970965
| DefKind::Enum
971966
| DefKind::Union
972967
| DefKind::Impl { .. }
@@ -1033,7 +1028,6 @@ fn should_encode_variances(def_kind: DefKind) -> bool {
10331028
| DefKind::Enum
10341029
| DefKind::Variant
10351030
| DefKind::OpaqueTy
1036-
| DefKind::ImplTraitPlaceholder
10371031
| DefKind::Fn
10381032
| DefKind::Ctor(..)
10391033
| DefKind::AssocFn => true,
@@ -1083,7 +1077,6 @@ fn should_encode_generics(def_kind: DefKind) -> bool {
10831077
| DefKind::AnonConst
10841078
| DefKind::InlineConst
10851079
| DefKind::OpaqueTy
1086-
| DefKind::ImplTraitPlaceholder
10871080
| DefKind::Impl { .. }
10881081
| DefKind::Field
10891082
| DefKind::TyParam
@@ -1134,19 +1127,6 @@ fn should_encode_type(tcx: TyCtxt<'_>, def_id: LocalDefId, def_kind: DefKind) ->
11341127
}
11351128
}
11361129

1137-
DefKind::ImplTraitPlaceholder => {
1138-
let parent_def_id = tcx.impl_trait_in_trait_parent_fn(def_id.to_def_id());
1139-
let assoc_item = tcx.associated_item(parent_def_id);
1140-
match assoc_item.container {
1141-
// Always encode an RPIT in an impl fn, since it always has a body
1142-
ty::AssocItemContainer::ImplContainer => true,
1143-
ty::AssocItemContainer::TraitContainer => {
1144-
// Encode an RPIT for a trait only if the trait has a default body
1145-
assoc_item.defaultness(tcx).has_value()
1146-
}
1147-
}
1148-
}
1149-
11501130
DefKind::AssocTy => {
11511131
let assoc_item = tcx.associated_item(def_id);
11521132
match assoc_item.container {
@@ -1192,7 +1172,6 @@ fn should_encode_fn_sig(def_kind: DefKind) -> bool {
11921172
| DefKind::Ctor(..)
11931173
| DefKind::TyAlias
11941174
| DefKind::OpaqueTy
1195-
| DefKind::ImplTraitPlaceholder
11961175
| DefKind::ForeignTy
11971176
| DefKind::Impl { .. }
11981177
| DefKind::AssocConst
@@ -1235,7 +1214,6 @@ fn should_encode_constness(def_kind: DefKind) -> bool {
12351214
| DefKind::TyAlias
12361215
| DefKind::OpaqueTy
12371216
| DefKind::Impl { of_trait: false }
1238-
| DefKind::ImplTraitPlaceholder
12391217
| DefKind::ForeignTy
12401218
| DefKind::Generator
12411219
| DefKind::ConstParam
@@ -1268,7 +1246,6 @@ fn should_encode_const(def_kind: DefKind) -> bool {
12681246
| DefKind::Static(..)
12691247
| DefKind::TyAlias
12701248
| DefKind::OpaqueTy
1271-
| DefKind::ImplTraitPlaceholder
12721249
| DefKind::ForeignTy
12731250
| DefKind::Impl { .. }
12741251
| DefKind::AssocFn
@@ -1289,11 +1266,8 @@ fn should_encode_const(def_kind: DefKind) -> bool {
12891266
}
12901267
}
12911268

1292-
// We only encode impl trait in trait when using `lower-impl-trait-in-trait-to-assoc-ty` unstable
1293-
// option.
12941269
fn should_encode_fn_impl_trait_in_trait<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
1295-
if tcx.lower_impl_trait_in_trait_to_assoc_ty()
1296-
&& let Some(assoc_item) = tcx.opt_associated_item(def_id)
1270+
if let Some(assoc_item) = tcx.opt_associated_item(def_id)
12971271
&& assoc_item.container == ty::AssocItemContainer::TraitContainer
12981272
&& assoc_item.kind == ty::AssocKind::Fn
12991273
{
@@ -1447,9 +1421,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
14471421
.is_type_alias_impl_trait
14481422
.set(def_id.index, self.tcx.is_type_alias_impl_trait(def_id));
14491423
}
1450-
if let DefKind::ImplTraitPlaceholder = def_kind {
1451-
self.encode_explicit_item_bounds(def_id);
1452-
}
14531424
if tcx.impl_method_has_trait_impl_trait_tys(def_id)
14541425
&& let Ok(table) = self.tcx.collect_return_position_impl_trait_in_trait_tys(def_id)
14551426
{

‎compiler/rustc_metadata/src/rmeta/table.rs

-1
Original file line numberDiff line numberDiff line change
@@ -142,7 +142,6 @@ fixed_size_enum! {
142142
( AnonConst )
143143
( InlineConst )
144144
( OpaqueTy )
145-
( ImplTraitPlaceholder )
146145
( Field )
147146
( LifetimeParam )
148147
( GlobalAsm )

‎compiler/rustc_middle/src/hir/map/mod.rs

+1-7
Original file line numberDiff line numberDiff line change
@@ -195,13 +195,7 @@ impl<'hir> Map<'hir> {
195195
ItemKind::Fn(..) => DefKind::Fn,
196196
ItemKind::Macro(_, macro_kind) => DefKind::Macro(macro_kind),
197197
ItemKind::Mod(..) => DefKind::Mod,
198-
ItemKind::OpaqueTy(ref opaque) => {
199-
if opaque.in_trait && !self.tcx.lower_impl_trait_in_trait_to_assoc_ty() {
200-
DefKind::ImplTraitPlaceholder
201-
} else {
202-
DefKind::OpaqueTy
203-
}
204-
}
198+
ItemKind::OpaqueTy(..) => DefKind::OpaqueTy,
205199
ItemKind::TyAlias(..) => DefKind::TyAlias,
206200
ItemKind::Enum(..) => DefKind::Enum,
207201
ItemKind::Struct(..) => DefKind::Struct,

‎compiler/rustc_middle/src/ty/context.rs

+4-10
Original file line numberDiff line numberDiff line change
@@ -1036,7 +1036,9 @@ impl<'tcx> TyCtxt<'tcx> {
10361036
scope_def_id: LocalDefId,
10371037
) -> Vec<&'tcx hir::Ty<'tcx>> {
10381038
let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
1039-
let Some(hir::FnDecl { output: hir::FnRetTy::Return(hir_output), .. }) = self.hir().fn_decl_by_hir_id(hir_id) else {
1039+
let Some(hir::FnDecl { output: hir::FnRetTy::Return(hir_output), .. }) =
1040+
self.hir().fn_decl_by_hir_id(hir_id)
1041+
else {
10401042
return vec![];
10411043
};
10421044

@@ -2002,16 +2004,8 @@ impl<'tcx> TyCtxt<'tcx> {
20022004
)
20032005
}
20042006

2005-
pub fn lower_impl_trait_in_trait_to_assoc_ty(self) -> bool {
2006-
self.sess.opts.unstable_opts.lower_impl_trait_in_trait_to_assoc_ty
2007-
}
2008-
20092007
pub fn is_impl_trait_in_trait(self, def_id: DefId) -> bool {
2010-
if self.lower_impl_trait_in_trait_to_assoc_ty() {
2011-
self.opt_rpitit_info(def_id).is_some()
2012-
} else {
2013-
self.def_kind(def_id) == DefKind::ImplTraitPlaceholder
2014-
}
2008+
self.opt_rpitit_info(def_id).is_some()
20152009
}
20162010

20172011
/// Named module children from all kinds of items, including imports.

0 commit comments

Comments
 (0)