Rollup merge of rust-lang#91984 - Aaron1011:rustc-middle-lifetime, r=…

…oli-obk

Remove `in_band_lifetimes` from `rustc_middle`

See rust-lang#91867

This was mostly straightforward. In several places, I take advantage
of the fact that lifetimes are non-hygenic: a macro declares the
'tcx' lifetime, which is then used in types passed in as macro
arguments.

compiler/rustc_macros/src/type_foldable.rs

@@ -1,10 +1,15 @@
 use quote::quote;
+use syn::parse_quote;
 
 pub fn type_foldable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
     if let syn::Data::Union(_) = s.ast().data {
         panic!("cannot derive on union")
     }
 
+    if !s.ast().generics.lifetimes().any(|lt| lt.lifetime.ident == "tcx") {
+        s.add_impl_generic(parse_quote! { 'tcx });
+    }
+
     s.add_bounds(synstructure::AddBounds::Generics);
     let body_visit = s.each(|bind| {
         quote! {

compiler/rustc_middle/src/dep_graph/dep_node.rs

@@ -201,7 +201,7 @@ crate fn make_compile_codegen_unit(tcx: TyCtxt<'_>, name: Symbol) -> DepNode {
 
 // WARNING: `construct` is generic and does not know that `CompileMonoItem` takes `MonoItem`s as keys.
 // Be very careful changing this type signature!
-crate fn make_compile_mono_item(tcx: TyCtxt<'tcx>, mono_item: &MonoItem<'tcx>) -> DepNode {
+crate fn make_compile_mono_item<'tcx>(tcx: TyCtxt<'tcx>, mono_item: &MonoItem<'tcx>) -> DepNode {
     DepNode::construct(tcx, DepKind::CompileMonoItem, mono_item)
 }
 
@@ -264,7 +264,7 @@ impl DepNodeExt for DepNode {
     /// DepNode. Condition (2) might not be fulfilled if a DepNode
     /// refers to something from the previous compilation session that
     /// has been removed.
-    fn extract_def_id(&self, tcx: TyCtxt<'tcx>) -> Option<DefId> {
+    fn extract_def_id<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Option<DefId> {
         if self.kind.fingerprint_style(tcx) == FingerprintStyle::DefPathHash {
             Some(tcx.def_path_hash_to_def_id(DefPathHash(self.hash.into())))
         } else {

compiler/rustc_middle/src/infer/canonical.rs

@@ -75,7 +75,7 @@ pub struct OriginalQueryValues<'tcx> {
     pub var_values: SmallVec<[GenericArg<'tcx>; 8]>,
 }
 
-impl Default for OriginalQueryValues<'tcx> {
+impl<'tcx> Default for OriginalQueryValues<'tcx> {
     fn default() -> Self {
         let mut universe_map = SmallVec::default();
         universe_map.push(ty::UniverseIndex::ROOT);

compiler/rustc_middle/src/infer/unify_key.rs

@@ -164,7 +164,7 @@ impl<'tcx> UnifyValue for ConstVarValue<'tcx> {
 
 impl<'tcx> EqUnifyValue for &'tcx ty::Const<'tcx> {}
 
-pub fn replace_if_possible<V, L>(
+pub fn replace_if_possible<'tcx, V, L>(
     table: &mut UnificationTable<InPlace<ty::ConstVid<'tcx>, V, L>>,
     c: &'tcx ty::Const<'tcx>,
 ) -> &'tcx ty::Const<'tcx>

compiler/rustc_middle/src/lib.rs

@@ -44,7 +44,6 @@
 #![feature(let_else)]
 #![feature(min_specialization)]
 #![feature(trusted_len)]
-#![feature(in_band_lifetimes)]
 #![feature(crate_visibility_modifier)]
 #![feature(associated_type_bounds)]
 #![feature(rustc_attrs)]

compiler/rustc_middle/src/lint.rs

@@ -212,7 +212,7 @@ pub fn struct_lint_level<'s, 'd>(
 ) {
     // Avoid codegen bloat from monomorphization by immediately doing dyn dispatch of `decorate` to
     // the "real" work.
-    fn struct_lint_level_impl(
+    fn struct_lint_level_impl<'s, 'd>(
         sess: &'s Session,
         lint: &'static Lint,
         level: Level,

compiler/rustc_middle/src/middle/stability.rs

@@ -229,7 +229,7 @@ pub fn deprecation_message_and_lint(
     )
 }
 
-pub fn early_report_deprecation(
+pub fn early_report_deprecation<'a>(
     lint_buffer: &'a mut LintBuffer,
     message: &str,
     suggestion: Option<Symbol>,

compiler/rustc_middle/src/mir/interpret/error.rs

@@ -63,7 +63,7 @@ impl fmt::Display for InterpErrorInfo<'_> {
     }
 }
 
-impl InterpErrorInfo<'tcx> {
+impl<'tcx> InterpErrorInfo<'tcx> {
     pub fn print_backtrace(&self) {
         if let Some(backtrace) = self.0.backtrace.as_ref() {
             print_backtrace(backtrace);

compiler/rustc_middle/src/mir/interpret/mod.rs

@@ -145,7 +145,7 @@ pub struct GlobalId<'tcx> {
     pub promoted: Option<mir::Promoted>,
 }
 
-impl GlobalId<'tcx> {
+impl<'tcx> GlobalId<'tcx> {
     pub fn display(self, tcx: TyCtxt<'tcx>) -> String {
         let instance_name = with_no_trimmed_paths(|| tcx.def_path_str(self.instance.def.def_id()));
         if let Some(promoted) = self.promoted {
@@ -273,7 +273,7 @@ pub struct AllocDecodingSession<'s> {
 
 impl<'s> AllocDecodingSession<'s> {
     /// Decodes an `AllocId` in a thread-safe way.
-    pub fn decode_alloc_id<D>(&self, decoder: &mut D) -> Result<AllocId, D::Error>
+    pub fn decode_alloc_id<'tcx, D>(&self, decoder: &mut D) -> Result<AllocId, D::Error>
     where
         D: TyDecoder<'tcx>,
     {
@@ -390,7 +390,7 @@ pub enum GlobalAlloc<'tcx> {
     Memory(&'tcx Allocation),
 }
 
-impl GlobalAlloc<'tcx> {
+impl<'tcx> GlobalAlloc<'tcx> {
     /// Panics if the `GlobalAlloc` does not refer to an `GlobalAlloc::Memory`
     #[track_caller]
     #[inline]

compiler/rustc_middle/src/mir/mod.rs

@@ -2033,7 +2033,7 @@ impl SourceScope {
     /// Finds the original HirId this MIR item came from.
     /// This is necessary after MIR optimizations, as otherwise we get a HirId
     /// from the function that was inlined instead of the function call site.
-    pub fn lint_root(
+    pub fn lint_root<'tcx>(
         self,
         source_scopes: &IndexVec<SourceScope, SourceScopeData<'tcx>>,
     ) -> Option<HirId> {
@@ -2543,7 +2543,7 @@ pub enum ConstantKind<'tcx> {
     Val(interpret::ConstValue<'tcx>, Ty<'tcx>),
 }
 
-impl Constant<'tcx> {
+impl<'tcx> Constant<'tcx> {
     pub fn check_static_ptr(&self, tcx: TyCtxt<'_>) -> Option<DefId> {
         match self.literal.const_for_ty()?.val.try_to_scalar() {
             Some(Scalar::Ptr(ptr, _size)) => match tcx.global_alloc(ptr.provenance) {
@@ -2562,14 +2562,14 @@ impl Constant<'tcx> {
     }
 }
 
-impl From<&'tcx ty::Const<'tcx>> for ConstantKind<'tcx> {
+impl<'tcx> From<&'tcx ty::Const<'tcx>> for ConstantKind<'tcx> {
     #[inline]
     fn from(ct: &'tcx ty::Const<'tcx>) -> Self {
         Self::Ty(ct)
     }
 }
 
-impl ConstantKind<'tcx> {
+impl<'tcx> ConstantKind<'tcx> {
     /// Returns `None` if the constant is not trivially safe for use in the type system.
     pub fn const_for_ty(&self) -> Option<&'tcx ty::Const<'tcx>> {
         match self {
@@ -2851,7 +2851,7 @@ impl<'tcx> Display for ConstantKind<'tcx> {
     }
 }
 
-fn pretty_print_const(
+fn pretty_print_const<'tcx>(
     c: &ty::Const<'tcx>,
     fmt: &mut Formatter<'_>,
     print_types: bool,
@@ -2866,7 +2866,7 @@ fn pretty_print_const(
     })
 }
 
-fn pretty_print_const_value(
+fn pretty_print_const_value<'tcx>(
     val: interpret::ConstValue<'tcx>,
     ty: Ty<'tcx>,
     fmt: &mut Formatter<'_>,
@@ -2913,12 +2913,12 @@ impl<'a, 'b> graph::GraphSuccessors<'b> for Body<'a> {
     type Iter = iter::Cloned<Successors<'b>>;
 }
 
-impl graph::GraphPredecessors<'graph> for Body<'tcx> {
+impl<'tcx, 'graph> graph::GraphPredecessors<'graph> for Body<'tcx> {
     type Item = BasicBlock;
     type Iter = std::iter::Copied<std::slice::Iter<'graph, BasicBlock>>;
 }
 
-impl graph::WithPredecessors for Body<'tcx> {
+impl<'tcx> graph::WithPredecessors for Body<'tcx> {
     #[inline]
     fn predecessors(&self, node: Self::Node) -> <Self as graph::GraphPredecessors<'_>>::Iter {
         self.predecessors()[node].iter().copied()

compiler/rustc_middle/src/mir/mono.rs

@@ -431,7 +431,7 @@ pub struct CodegenUnitNameBuilder<'tcx> {
     cache: FxHashMap<CrateNum, String>,
 }
 
-impl CodegenUnitNameBuilder<'tcx> {
+impl<'tcx> CodegenUnitNameBuilder<'tcx> {
     pub fn new(tcx: TyCtxt<'tcx>) -> Self {
         CodegenUnitNameBuilder { tcx, cache: Default::default() }
     }

compiler/rustc_middle/src/mir/pretty.rs

@@ -167,8 +167,8 @@ fn dump_matched_mir_node<'tcx, F>(
 
 /// Returns the file basename portion (without extension) of a filename path
 /// where we should dump a MIR representation output files.
-fn dump_file_basename(
-    tcx: TyCtxt<'_>,
+fn dump_file_basename<'tcx>(
+    tcx: TyCtxt<'tcx>,
     pass_num: Option<&dyn Display>,
     pass_name: &str,
     disambiguator: &dyn Display,
@@ -251,8 +251,8 @@ fn create_dump_file_with_basename(
 /// bit of MIR-related data. Used by `mir-dump`, but also by other
 /// bits of code (e.g., NLL inference) that dump graphviz data or
 /// other things, and hence takes the extension as an argument.
-pub fn create_dump_file(
-    tcx: TyCtxt<'_>,
+pub fn create_dump_file<'tcx>(
+    tcx: TyCtxt<'tcx>,
     extension: &str,
     pass_num: Option<&dyn Display>,
     pass_name: &str,
@@ -419,15 +419,15 @@ struct ExtraComments<'tcx> {
     comments: Vec<String>,
 }
 
-impl ExtraComments<'tcx> {
+impl<'tcx> ExtraComments<'tcx> {
     fn push(&mut self, lines: &str) {
         for line in lines.split('\n') {
             self.comments.push(line.to_string());
         }
     }
 }
 
-fn use_verbose(ty: &&TyS<'tcx>, fn_def: bool) -> bool {
+fn use_verbose<'tcx>(ty: &&TyS<'tcx>, fn_def: bool) -> bool {
     match ty.kind() {
         ty::Int(_) | ty::Uint(_) | ty::Bool | ty::Char | ty::Float(_) => false,
         // Unit type
@@ -439,7 +439,7 @@ fn use_verbose(ty: &&TyS<'tcx>, fn_def: bool) -> bool {
     }
 }
 
-impl Visitor<'tcx> for ExtraComments<'tcx> {
+impl<'tcx> Visitor<'tcx> for ExtraComments<'tcx> {
     fn visit_constant(&mut self, constant: &Constant<'tcx>, location: Location) {
         self.super_constant(constant, location);
         let Constant { span, user_ty, literal } = constant;
@@ -762,7 +762,7 @@ pub fn write_allocations<'tcx>(
 /// After the hex dump, an ascii dump follows, replacing all unprintable characters (control
 /// characters or characters whose value is larger than 127) with a `.`
 /// This also prints relocations adequately.
-pub fn display_allocation<Tag, Extra>(
+pub fn display_allocation<'a, 'tcx, Tag, Extra>(
     tcx: TyCtxt<'tcx>,
     alloc: &'a Allocation<Tag, Extra>,
 ) -> RenderAllocation<'a, 'tcx, Tag, Extra> {
@@ -775,7 +775,9 @@ pub struct RenderAllocation<'a, 'tcx, Tag, Extra> {
     alloc: &'a Allocation<Tag, Extra>,
 }
 
-impl<Tag: Provenance, Extra> std::fmt::Display for RenderAllocation<'a, 'tcx, Tag, Extra> {
+impl<'a, 'tcx, Tag: Provenance, Extra> std::fmt::Display
+    for RenderAllocation<'a, 'tcx, Tag, Extra>
+{
     fn fmt(&self, w: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let RenderAllocation { tcx, alloc } = *self;
         write!(w, "size: {}, align: {})", alloc.size().bytes(), alloc.align.bytes())?;
@@ -818,7 +820,7 @@ fn write_allocation_newline(
 /// The `prefix` argument allows callers to add an arbitrary prefix before each line (even if there
 /// is only one line). Note that your prefix should contain a trailing space as the lines are
 /// printed directly after it.
-fn write_allocation_bytes<Tag: Provenance, Extra>(
+fn write_allocation_bytes<'tcx, Tag: Provenance, Extra>(
     tcx: TyCtxt<'tcx>,
     alloc: &Allocation<Tag, Extra>,
     w: &mut dyn std::fmt::Write,

compiler/rustc_middle/src/mir/traversal.rs

@@ -300,7 +300,7 @@ pub fn reachable<'a, 'tcx>(
 }
 
 /// Returns a `BitSet` containing all basic blocks reachable from the `START_BLOCK`.
-pub fn reachable_as_bitset(body: &Body<'tcx>) -> BitSet<BasicBlock> {
+pub fn reachable_as_bitset<'tcx>(body: &Body<'tcx>) -> BitSet<BasicBlock> {
     let mut iter = preorder(body);
     (&mut iter).for_each(drop);
     iter.visited

compiler/rustc_middle/src/mir/visit.rs

@@ -965,7 +965,7 @@ macro_rules! visit_place_fns {
             }
         }
 
-        fn process_projection(
+        fn process_projection<'a>(
             &mut self,
             projection: &'a [PlaceElem<'tcx>],
             location: Location,

compiler/rustc_middle/src/traits/mod.rs

@@ -101,7 +101,7 @@ impl<'tcx> fmt::Debug for ObligationCause<'tcx> {
     }
 }
 
-impl Deref for ObligationCause<'tcx> {
+impl<'tcx> Deref for ObligationCause<'tcx> {
     type Target = ObligationCauseData<'tcx>;
 
     #[inline(always)]

compiler/rustc_middle/src/traits/specialization_graph.rs

@@ -216,7 +216,7 @@ impl<'tcx> Ancestors<'tcx> {
 ///
 /// Returns `Err` if an error was reported while building the specialization
 /// graph.
-pub fn ancestors(
+pub fn ancestors<'tcx>(
     tcx: TyCtxt<'tcx>,
     trait_def_id: DefId,
     start_from_impl: DefId,

compiler/rustc_middle/src/traits/structural_impls.rs

@@ -74,7 +74,7 @@ impl<N: fmt::Debug> fmt::Debug for traits::ImplSourceBuiltinData<N> {
     }
 }
 
-impl<N: fmt::Debug> fmt::Debug for traits::ImplSourceTraitUpcastingData<'tcx, N> {
+impl<'tcx, N: fmt::Debug> fmt::Debug for traits::ImplSourceTraitUpcastingData<'tcx, N> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(
             f,

compiler/rustc_middle/src/ty/_match.rs

@@ -23,13 +23,13 @@ pub struct Match<'tcx> {
     param_env: ty::ParamEnv<'tcx>,
 }
 
-impl Match<'tcx> {
+impl<'tcx> Match<'tcx> {
     pub fn new(tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> Match<'tcx> {
         Match { tcx, param_env }
     }
 }
 
-impl TypeRelation<'tcx> for Match<'tcx> {
+impl<'tcx> TypeRelation<'tcx> for Match<'tcx> {
     fn tag(&self) -> &'static str {
         "Match"
     }

compiler/rustc_middle/src/ty/adjustment.rs

@@ -83,7 +83,7 @@ pub struct Adjustment<'tcx> {
     pub target: Ty<'tcx>,
 }
 
-impl Adjustment<'tcx> {
+impl<'tcx> Adjustment<'tcx> {
     pub fn is_region_borrow(&self) -> bool {
         matches!(self.kind, Adjust::Borrow(AutoBorrow::Ref(..)))
     }

compiler/rustc_middle/src/ty/assoc.rs

@@ -139,7 +139,7 @@ impl<'tcx> AssocItems<'tcx> {
     /// Multiple items may have the same name if they are in different `Namespace`s. For example,
     /// an associated type can have the same name as a method. Use one of the `find_by_name_and_*`
     /// methods below if you know which item you are looking for.
-    pub fn filter_by_name(
+    pub fn filter_by_name<'a>(
         &'a self,
         tcx: TyCtxt<'a>,
         ident: Ident,

compiler/rustc_middle/src/ty/closure.rs

@@ -156,7 +156,7 @@ pub struct CapturedPlace<'tcx> {
     pub mutability: hir::Mutability,
 }
 
-impl CapturedPlace<'tcx> {
+impl<'tcx> CapturedPlace<'tcx> {
     pub fn to_string(&self, tcx: TyCtxt<'tcx>) -> String {
         place_to_string_for_capture(tcx, &self.place)
     }
@@ -328,7 +328,7 @@ pub struct CaptureInfo<'tcx> {
     pub capture_kind: UpvarCapture<'tcx>,
 }
 
-pub fn place_to_string_for_capture(tcx: TyCtxt<'tcx>, place: &HirPlace<'tcx>) -> String {
+pub fn place_to_string_for_capture<'tcx>(tcx: TyCtxt<'tcx>, place: &HirPlace<'tcx>) -> String {
     let mut curr_string: String = match place.base {
         HirPlaceBase::Upvar(upvar_id) => tcx.hir().name(upvar_id.var_path.hir_id).to_string(),
         _ => bug!("Capture_information should only contain upvars"),

compiler/rustc_middle/src/ty/codec.rs

@@ -76,7 +76,11 @@ pub trait RefDecodable<'tcx, D: TyDecoder<'tcx>> {
 }
 
 /// Encode the given value or a previously cached shorthand.
-pub fn encode_with_shorthand<E, T, M>(encoder: &mut E, value: &T, cache: M) -> Result<(), E::Error>
+pub fn encode_with_shorthand<'tcx, E, T, M>(
+    encoder: &mut E,
+    value: &T,
+    cache: M,
+) -> Result<(), E::Error>
 where
     E: TyEncoder<'tcx>,
     M: for<'b> Fn(&'b mut E) -> &'b mut FxHashMap<T, usize>,

compiler/rustc_middle/src/ty/consts/int.rs

@@ -234,7 +234,7 @@ impl ScalarInt {
     }
 
     #[inline]
-    pub fn try_to_machine_usize(&self, tcx: TyCtxt<'tcx>) -> Result<u64, Size> {
+    pub fn try_to_machine_usize<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Result<u64, Size> {
         Ok(self.to_bits(tcx.data_layout.pointer_size)? as u64)
     }
 }

compiler/rustc_middle/src/ty/consts/valtree.rs

@@ -27,7 +27,7 @@ pub enum ValTree<'tcx> {
     Branch(&'tcx [ValTree<'tcx>]),
 }
 
-impl ValTree<'tcx> {
+impl<'tcx> ValTree<'tcx> {
     pub fn zst() -> Self {
         Self::Branch(&[])
     }