diff --git a/compiler/rustc_middle/src/middle/autodiff_attrs.rs b/compiler/rustc_middle/src/middle/autodiff_attrs.rs
deleted file mode 100644
index 2412df725fe2b..0000000000000
--- a/compiler/rustc_middle/src/middle/autodiff_attrs.rs
+++ /dev/null
@@ -1,94 +0,0 @@
-use crate::middle::typetree::TypeTree;
-use std::str::FromStr;
-
-#[allow(dead_code)]
-#[derive(Clone, Copy, Eq, PartialEq, TyEncodable, TyDecodable, HashStable, Debug)]
-pub enum DiffMode {
-    Inactive,
-    Source,
-    Forward,
-    Reverse,
-}
-
-#[allow(dead_code)]
-#[derive(Clone, Copy, Eq, PartialEq, TyEncodable, TyDecodable, HashStable, Debug)]
-pub enum DiffActivity {
-    None,
-    Active,
-    Const,
-    Duplicated,
-    DuplicatedNoNeed,
-}
-
-impl FromStr for DiffActivity {
-    type Err = ();
-
-    fn from_str(s: &str) -> Result<DiffActivity, ()> {
-        match s {
-            "None" => Ok(DiffActivity::None),
-            "Active" => Ok(DiffActivity::Active),
-            "Const" => Ok(DiffActivity::Const),
-            "Duplicated" => Ok(DiffActivity::Duplicated),
-            "DuplicatedNoNeed" => Ok(DiffActivity::DuplicatedNoNeed),
-            _ => Err(()),
-        }
-    }
-}
-
-#[allow(dead_code)]
-#[derive(Clone, Eq, PartialEq, TyEncodable, TyDecodable, HashStable, Debug)]
-pub struct AutoDiffAttrs {
-    pub mode: DiffMode,
-    pub ret_activity: DiffActivity,
-    pub input_activity: Vec<DiffActivity>,
-}
-
-impl AutoDiffAttrs {
-    pub fn inactive() -> Self {
-        AutoDiffAttrs {
-            mode: DiffMode::Inactive,
-            ret_activity: DiffActivity::None,
-            input_activity: Vec::new(),
-        }
-    }
-
-    pub fn is_active(&self) -> bool {
-        match self.mode {
-            DiffMode::Inactive => false,
-            _ => true,
-        }
-    }
-
-    pub fn is_source(&self) -> bool {
-        match self.mode {
-            DiffMode::Source => true,
-            _ => false,
-        }
-    }
-    pub fn apply_autodiff(&self) -> bool {
-        match self.mode {
-            DiffMode::Inactive => false,
-            DiffMode::Source => false,
-            _ => true,
-        }
-    }
-
-    pub fn into_item(
-        self,
-        source: String,
-        target: String,
-        inputs: Vec<TypeTree>,
-        output: TypeTree,
-    ) -> AutoDiffItem {
-        AutoDiffItem { source, target, inputs, output, attrs: self }
-    }
-}
-
-#[derive(Clone, Eq, PartialEq, TyEncodable, TyDecodable, HashStable, Debug)]
-pub struct AutoDiffItem {
-    pub source: String,
-    pub target: String,
-    pub attrs: AutoDiffAttrs,
-    pub inputs: Vec<TypeTree>,
-    pub output: TypeTree,
-}
diff --git a/compiler/rustc_middle/src/middle/mod.rs b/compiler/rustc_middle/src/middle/mod.rs
index 786ad3361ff2e..85c5af9ca13cb 100644
--- a/compiler/rustc_middle/src/middle/mod.rs
+++ b/compiler/rustc_middle/src/middle/mod.rs
@@ -32,7 +32,6 @@ pub mod privacy;
 pub mod region;
 pub mod resolve_bound_vars;
 pub mod stability;
-pub mod typetree;
 
 pub fn provide(providers: &mut crate::query::Providers) {
     limits::provide(providers);
diff --git a/compiler/rustc_middle/src/middle/typetree.rs b/compiler/rustc_middle/src/middle/typetree.rs
deleted file mode 100644
index 4049d32540bd2..0000000000000
--- a/compiler/rustc_middle/src/middle/typetree.rs
+++ /dev/null
@@ -1,39 +0,0 @@
-use std::fmt;
-#[derive(Clone, Eq, PartialEq, TyEncodable, TyDecodable, HashStable, Debug)]
-pub enum Kind {
-    Anything,
-    Integer,
-    Pointer,
-    Half,
-    Float,
-    Double,
-    Unknown,
-}
-
-#[derive(Clone, Eq, PartialEq, TyEncodable, TyDecodable, HashStable, Debug)]
-pub struct TypeTree(pub Vec<Type>);
-
-#[derive(Clone, Eq, PartialEq, TyEncodable, TyDecodable, HashStable, Debug)]
-pub struct Type {
-    pub offset: isize,
-    pub size: usize,
-    pub kind: Kind,
-    pub child: TypeTree,
-}
-
-impl Type {
-    pub fn add_offset(self, add: isize) -> Self {
-        let offset = match self.offset {
-            -1 => add,
-            x => add + x,
-        };
-
-        Self { size: self.size, kind: self.kind, child: self.child, offset }
-    }
-}
-
-impl fmt::Display for Type {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        <Self as fmt::Debug>::fmt(self, f)
-    }
-}