Use less rustc_type_ir in the compiler codebase

This commit does the following:
 - Replaces use of rustc_type_ir by rustc_middle
 - Removes the rustc_type_ir dependency
 - The DelayedSet type is exposed by rustc_middle so everything can be
   accessed through rustc_middle in a coherent manner.

Cargo.lock

@@ -4494,7 +4494,6 @@ dependencies = [
  "rustc_session",
  "rustc_span",
  "rustc_transmute",
- "rustc_type_ir",
  "smallvec",
  "thin-vec",
  "tracing",

compiler/rustc_middle/src/ty/mod.rs

@@ -50,6 +50,7 @@
 pub use rustc_session::lint::RegisteredTools;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::{DUMMY_SP, ExpnId, ExpnKind, Ident, Span, Symbol, kw, sym};
+pub use rustc_type_ir::data_structures::DelayedSet;
 pub use rustc_type_ir::relate::VarianceDiagInfo;
 pub use rustc_type_ir::*;
 use tracing::{debug, instrument};

compiler/rustc_trait_selection/Cargo.toml

@@ -21,7 +21,6 @@ rustc_parse_format = { path = "../rustc_parse_format" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_transmute = { path = "../rustc_transmute", features = ["rustc"] }
-rustc_type_ir = { path = "../rustc_type_ir" }
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
 thin-vec = "0.2"
 tracing = "0.1"

compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs

@@ -15,10 +15,9 @@
 use rustc_middle::ty::print::{FmtPrinter, PrettyPrinter, Print, Printer};
 use rustc_middle::ty::{
     self, GenericArg, GenericArgKind, GenericArgsRef, InferConst, IsSuggestable, Term, TermKind,
-    Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeckResults,
+    Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitableExt, TypeckResults,
 };
 use rustc_span::{BytePos, DUMMY_SP, FileName, Ident, Span, sym};
-use rustc_type_ir::TypeVisitableExt;
 use tracing::{debug, instrument, warn};
 
 use super::nice_region_error::placeholder_error::Highlighted;

compiler/rustc_trait_selection/src/error_reporting/infer/region.rs

@@ -11,9 +11,10 @@
 use rustc_middle::bug;
 use rustc_middle::traits::ObligationCauseCode;
 use rustc_middle::ty::error::TypeError;
-use rustc_middle::ty::{self, IsSuggestable, Region, Ty, TyCtxt, TypeVisitableExt as _};
+use rustc_middle::ty::{
+    self, IsSuggestable, Region, Ty, TyCtxt, TypeVisitableExt as _, Upcast as _,
+};
 use rustc_span::{BytePos, ErrorGuaranteed, Span, Symbol, kw};
-use rustc_type_ir::Upcast as _;
 use tracing::{debug, instrument};
 
 use super::ObligationCauseAsDiagArg;

compiler/rustc_trait_selection/src/error_reporting/traits/overflow.rs

@@ -5,10 +5,9 @@
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_infer::traits::{Obligation, PredicateObligation};
 use rustc_middle::ty::print::{FmtPrinter, Print};
-use rustc_middle::ty::{self, TyCtxt};
+use rustc_middle::ty::{self, TyCtxt, Upcast};
 use rustc_session::Limit;
 use rustc_span::Span;
-use rustc_type_ir::Upcast;
 use tracing::debug;
 
 use crate::error_reporting::TypeErrCtxt;

compiler/rustc_trait_selection/src/solve/delegate.rs

@@ -8,10 +8,10 @@
 };
 use rustc_infer::infer::{InferCtxt, RegionVariableOrigin, TyCtxtInferExt};
 use rustc_infer::traits::solve::Goal;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeVisitableExt as _};
+use rustc_middle::traits::query::NoSolution;
+use rustc_middle::traits::solve::Certainty;
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeVisitableExt as _, TypingMode};
 use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span};
-use rustc_type_ir::TypingMode;
-use rustc_type_ir::solve::{Certainty, NoSolution};
 
 use crate::traits::{EvaluateConstErr, specialization_graph};
 
@@ -155,7 +155,7 @@ fn instantiate_canonical_var_with_infer(
 
     fn register_hidden_type_in_storage(
         &self,
-        opaque_type_key: rustc_type_ir::OpaqueTypeKey<Self::Interner>,
+        opaque_type_key: ty::OpaqueTypeKey<'tcx>,
         hidden_ty: <Self::Interner as ty::Interner>::Ty,
         span: <Self::Interner as ty::Interner>::Span,
     ) -> Option<<Self::Interner as ty::Interner>::Ty> {

compiler/rustc_trait_selection/src/solve/fulfill.rs

@@ -10,11 +10,10 @@
     FromSolverError, PredicateObligation, PredicateObligations, TraitEngine,
 };
 use rustc_middle::ty::{
-    self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor, TypingMode,
+    self, DelayedSet, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor, TypingMode,
 };
 use rustc_next_trait_solver::solve::{GenerateProofTree, HasChanged, SolverDelegateEvalExt as _};
 use rustc_span::Span;
-use rustc_type_ir::data_structures::DelayedSet;
 use tracing::instrument;
 
 use self::derive_errors::*;

compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs

@@ -7,11 +7,11 @@
     self, MismatchedProjectionTypes, Obligation, ObligationCause, ObligationCauseCode,
     PredicateObligation, SelectionError,
 };
+use rustc_middle::traits::query::NoSolution;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_middle::{bug, span_bug};
 use rustc_next_trait_solver::solve::{GenerateProofTree, SolverDelegateEvalExt as _};
-use rustc_type_ir::solve::NoSolution;
 use tracing::{instrument, trace};
 
 use crate::solve::delegate::SolverDelegate;

compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs

@@ -13,9 +13,9 @@
 use rustc_middle::ty::{
     self, EarlyBinder, GenericArgs, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable,
     TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor, TypingMode, Upcast,
+    elaborate,
 };
 use rustc_span::Span;
-use rustc_type_ir::elaborate;
 use smallvec::SmallVec;
 use tracing::{debug, instrument};
 

compiler/rustc_trait_selection/src/traits/effects.rs

@@ -4,10 +4,10 @@
     ImplDerivedHostCause, ImplSource, Obligation, ObligationCauseCode, PredicateObligation,
 };
 use rustc_middle::span_bug;
+use rustc_middle::traits::query::NoSolution;
+use rustc_middle::ty::elaborate::elaborate;
 use rustc_middle::ty::fast_reject::DeepRejectCtxt;
 use rustc_middle::ty::{self, TypingMode};
-use rustc_type_ir::elaborate::elaborate;
-use rustc_type_ir::solve::NoSolution;
 use thin_vec::{ThinVec, thin_vec};
 
 use super::SelectionContext;

compiler/rustc_trait_selection/src/traits/engine.rs

@@ -14,8 +14,8 @@
 use rustc_middle::arena::ArenaAllocatable;
 use rustc_middle::traits::query::NoSolution;
 use rustc_middle::ty::error::TypeError;
+use rustc_middle::ty::relate::Relate;
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, Upcast, Variance};
-use rustc_type_ir::relate::Relate;
 
 use super::{FromSolverError, FulfillmentContext, ScrubbedTraitError, TraitEngine};
 use crate::error_reporting::InferCtxtErrorExt;

compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs

@@ -6,10 +6,10 @@
 use rustc_infer::traits::query::type_op::ImpliedOutlivesBounds;
 use rustc_middle::infer::canonical::CanonicalQueryResponse;
 use rustc_middle::traits::ObligationCause;
+use rustc_middle::ty::outlives::{Component, push_outlives_components};
 use rustc_middle::ty::{self, ParamEnvAnd, Ty, TyCtxt, TypeVisitable, TypeVisitor};
 use rustc_span::def_id::CRATE_DEF_ID;
 use rustc_span::{DUMMY_SP, Span, sym};
-use rustc_type_ir::outlives::{Component, push_outlives_components};
 use smallvec::{SmallVec, smallvec};
 
 use crate::traits::query::NoSolution;

compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs

@@ -14,9 +14,8 @@
 use rustc_hir as hir;
 use rustc_infer::traits::{Obligation, PolyTraitObligation, SelectionError};
 use rustc_middle::ty::fast_reject::DeepRejectCtxt;
-use rustc_middle::ty::{self, Ty, TypeVisitableExt, TypingMode};
+use rustc_middle::ty::{self, Ty, TypeVisitableExt, TypingMode, elaborate};
 use rustc_middle::{bug, span_bug};
-use rustc_type_ir::elaborate;
 use tracing::{debug, instrument, trace};
 
 use super::SelectionCandidate::*;

compiler/rustc_trait_selection/src/traits/select/confirmation.rs

@@ -15,10 +15,9 @@
 use rustc_infer::infer::{DefineOpaqueTypes, HigherRankedType, InferOk};
 use rustc_infer::traits::ObligationCauseCode;
 use rustc_middle::traits::{BuiltinImplSource, SignatureMismatchData};
-use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, Upcast};
+use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, Upcast, elaborate};
 use rustc_middle::{bug, span_bug};
 use rustc_span::def_id::DefId;
-use rustc_type_ir::elaborate;
 use thin_vec::thin_vec;
 use tracing::{debug, instrument};
 

compiler/rustc_trait_selection/src/traits/select/mod.rs

@@ -28,10 +28,9 @@
 use rustc_middle::ty::print::{PrintTraitRefExt as _, with_no_trimmed_paths};
 use rustc_middle::ty::{
     self, GenericArgsRef, PolyProjectionPredicate, Ty, TyCtxt, TypeFoldable, TypeVisitableExt,
-    TypingMode, Upcast,
+    TypingMode, Upcast, elaborate,
 };
 use rustc_span::{Symbol, sym};
-use rustc_type_ir::elaborate;
 use tracing::{debug, instrument, trace};
 
 use self::EvaluationResult::*;

compiler/rustc_trait_selection/src/traits/specialize/mod.rs

@@ -18,11 +18,11 @@
 use rustc_infer::traits::Obligation;
 use rustc_middle::bug;
 use rustc_middle::query::LocalCrate;
+use rustc_middle::traits::query::NoSolution;
 use rustc_middle::ty::print::PrintTraitRefExt as _;
 use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, TypeVisitableExt, TypingMode};
 use rustc_session::lint::builtin::COHERENCE_LEAK_CHECK;
 use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span, sym};
-use rustc_type_ir::solve::NoSolution;
 use specialization_graph::GraphExt;
 use tracing::{debug, instrument};