From ee47480f4cae83279d884d6bcc9e5e6ddf3334b8 Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Mon, 27 May 2024 18:32:17 -0400
Subject: [PATCH] Yeet PolyFnSig from Interner

---
 compiler/rustc_middle/src/ty/context.rs          |  1 -
 compiler/rustc_middle/src/ty/structural_impls.rs | 12 ------------
 compiler/rustc_type_ir/src/binder.rs             | 15 ++++++++++++++-
 compiler/rustc_type_ir/src/interner.rs           |  1 -
 compiler/rustc_type_ir/src/ty_kind.rs            |  2 +-
 5 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index c2219fba023bc..30dd887c88a2a 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -113,7 +113,6 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
 
     type ErrorGuaranteed = ErrorGuaranteed;
     type BoundExistentialPredicates = &'tcx List<PolyExistentialPredicate<'tcx>>;
-    type PolyFnSig = PolyFnSig<'tcx>;
     type AllocId = crate::mir::interpret::AllocId;
 
     type Pat = Pattern<'tcx>;
diff --git a/compiler/rustc_middle/src/ty/structural_impls.rs b/compiler/rustc_middle/src/ty/structural_impls.rs
index af3aa3b56f7bb..90791bdd20dcd 100644
--- a/compiler/rustc_middle/src/ty/structural_impls.rs
+++ b/compiler/rustc_middle/src/ty/structural_impls.rs
@@ -259,18 +259,6 @@ impl<'tcx> DebugWithInfcx<TyCtxt<'tcx>> for Region<'tcx> {
     }
 }
 
-impl<'tcx, T: DebugWithInfcx<TyCtxt<'tcx>>> DebugWithInfcx<TyCtxt<'tcx>> for ty::Binder<'tcx, T> {
-    fn fmt<Infcx: InferCtxtLike<Interner = TyCtxt<'tcx>>>(
-        this: WithInfcx<'_, Infcx, &Self>,
-        f: &mut core::fmt::Formatter<'_>,
-    ) -> core::fmt::Result {
-        f.debug_tuple("Binder")
-            .field(&this.map(|data| data.as_ref().skip_binder()))
-            .field(&this.data.bound_vars())
-            .finish()
-    }
-}
-
 ///////////////////////////////////////////////////////////////////////////
 // Atomic structs
 //
diff --git a/compiler/rustc_type_ir/src/binder.rs b/compiler/rustc_type_ir/src/binder.rs
index e50d59ba5f0e6..9a2c9059967b1 100644
--- a/compiler/rustc_type_ir/src/binder.rs
+++ b/compiler/rustc_type_ir/src/binder.rs
@@ -8,11 +8,12 @@ use rustc_macros::{HashStable_NoContext, TyDecodable, TyEncodable};
 use rustc_serialize::Decodable;
 use tracing::debug;
 
+use crate::debug::{DebugWithInfcx, WithInfcx};
 use crate::fold::{FallibleTypeFolder, TypeFoldable, TypeFolder, TypeSuperFoldable};
 use crate::inherent::*;
 use crate::lift::Lift;
 use crate::visit::{Flags, TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor};
-use crate::{self as ty, Interner, SsoHashSet};
+use crate::{self as ty, InferCtxtLike, Interner, SsoHashSet};
 
 /// Binder is a binder for higher-ranked lifetimes or types. It is part of the
 /// compiler's representation for things like `for<'a> Fn(&'a isize)`
@@ -55,6 +56,18 @@ where
     }
 }
 
+impl<I: Interner, T: DebugWithInfcx<I>> DebugWithInfcx<I> for ty::Binder<I, T> {
+    fn fmt<Infcx: InferCtxtLike<Interner = I>>(
+        this: WithInfcx<'_, Infcx, &Self>,
+        f: &mut core::fmt::Formatter<'_>,
+    ) -> core::fmt::Result {
+        f.debug_tuple("Binder")
+            .field(&this.map(|data| data.as_ref().skip_binder()))
+            .field(&this.data.bound_vars())
+            .finish()
+    }
+}
+
 macro_rules! impl_binder_encode_decode {
     ($($t:ty),+ $(,)?) => {
         $(
diff --git a/compiler/rustc_type_ir/src/interner.rs b/compiler/rustc_type_ir/src/interner.rs
index 2a228c973d34a..ca39318cc0c8b 100644
--- a/compiler/rustc_type_ir/src/interner.rs
+++ b/compiler/rustc_type_ir/src/interner.rs
@@ -69,7 +69,6 @@ pub trait Interner:
     // Things stored inside of tys
     type ErrorGuaranteed: Copy + Debug + Hash + Eq;
     type BoundExistentialPredicates: Copy + DebugWithInfcx<Self> + Hash + Eq;
-    type PolyFnSig: Copy + DebugWithInfcx<Self> + Hash + Eq;
     type AllocId: Copy + Debug + Hash + Eq;
     type Pat: Copy + Debug + Hash + Eq + DebugWithInfcx<Self>;
     type Safety: Safety<Self>;
diff --git a/compiler/rustc_type_ir/src/ty_kind.rs b/compiler/rustc_type_ir/src/ty_kind.rs
index 38082bf3c16fb..aa285169f276d 100644
--- a/compiler/rustc_type_ir/src/ty_kind.rs
+++ b/compiler/rustc_type_ir/src/ty_kind.rs
@@ -141,7 +141,7 @@ pub enum TyKind<I: Interner> {
     /// fn foo() -> i32 { 1 }
     /// let bar: fn() -> i32 = foo;
     /// ```
-    FnPtr(I::PolyFnSig),
+    FnPtr(ty::Binder<I, FnSig<I>>),
 
     /// A trait object. Written as `dyn for<'b> Trait<'b, Assoc = u32> + Send + 'a`.
     Dynamic(I::BoundExistentialPredicates, I::Region, DynKind),