1 files changed, 34 insertions, 11 deletions

diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
index 30b59da78..428fde642 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
@@ -17,11 +17,10 @@ use rustc_infer::infer::error_reporting::TypeErrCtxt;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_middle::infer::unify_key::{ConstVariableOrigin, ConstVariableOriginKind};
 use rustc_middle::ty::subst::GenericArgKind;
-use rustc_middle::ty::visit::TypeVisitable;
-use rustc_middle::ty::{self, Const, Ty, TyCtxt};
+use rustc_middle::ty::{self, Const, Ty, TyCtxt, TypeVisitable};
 use rustc_session::Session;
 use rustc_span::symbol::Ident;
-use rustc_span::{self, Span};
+use rustc_span::{self, Span, DUMMY_SP};
 use rustc_trait_selection::traits::{ObligationCause, ObligationCauseCode, ObligationCtxt};
 
 use std::cell::{Cell, RefCell};
@@ -176,6 +175,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     fn_sig
                 })
             }),
+            autoderef_steps: Box::new(|ty| {
+                let mut autoderef = self.autoderef(DUMMY_SP, ty).silence_errors();
+                let mut steps = vec![];
+                while let Some((ty, _)) = autoderef.next() {
+                    steps.push((ty, autoderef.current_obligations()));
+                }
+                steps
+            }),
         }
     }
 
@@ -287,8 +294,7 @@ impl<'a, 'tcx> AstConv<'tcx> for FnCtxt<'a, 'tcx> {
             poly_trait_ref,
         );
 
-        let item_substs = <dyn AstConv<'tcx>>::create_substs_for_associated_item(
-            self,
+        let item_substs = self.astconv().create_substs_for_associated_item(
             span,
             item_def_id,
             item_segment,
@@ -298,11 +304,14 @@ impl<'a, 'tcx> AstConv<'tcx> for FnCtxt<'a, 'tcx> {
         self.tcx().mk_projection(item_def_id, item_substs)
     }
 
-    fn normalize_ty(&self, span: Span, ty: Ty<'tcx>) -> Ty<'tcx> {
-        if ty.has_escaping_bound_vars() {
-            ty // FIXME: normalization and escaping regions
-        } else {
-            self.normalize(span, ty)
+    fn probe_adt(&self, span: Span, ty: Ty<'tcx>) -> Option<ty::AdtDef<'tcx>> {
+        match ty.kind() {
+            ty::Adt(adt_def, _) => Some(*adt_def),
+            // FIXME(#104767): Should we handle bound regions here?
+            ty::Alias(ty::Projection, _) if !ty.has_escaping_bound_vars() => {
+                self.normalize(span, ty).ty_adt_def()
+            }
+            _ => None,
         }
     }
 
@@ -310,7 +319,21 @@ impl<'a, 'tcx> AstConv<'tcx> for FnCtxt<'a, 'tcx> {
         self.infcx.set_tainted_by_errors(e)
     }
 
-    fn record_ty(&self, hir_id: hir::HirId, ty: Ty<'tcx>, _span: Span) {
+    fn record_ty(&self, hir_id: hir::HirId, ty: Ty<'tcx>, span: Span) {
+        // FIXME: normalization and escaping regions
+        let ty = if !ty.has_escaping_bound_vars() { self.normalize(span, ty) } else { ty };
         self.write_ty(hir_id, ty)
     }
 }
+
+/// Represents a user-provided type in the raw form (never normalized).
+///
+/// This is a bridge between the interface of `AstConv`, which outputs a raw `Ty`,
+/// and the API in this module, which expect `Ty` to be fully normalized.
+#[derive(Clone, Copy, Debug)]
+pub struct RawTy<'tcx> {
+    pub raw: Ty<'tcx>,
+
+    /// The normalized form of `raw`, stored here for efficiency.
+    pub normalized: Ty<'tcx>,
+}