Remove ty from CloneCopyShim so that it creates a single shim for all monomorphizations

Author: Manishearth

src/librustc/ich/impls_ty.rs

@@ -758,7 +758,9 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for ty::InstanceDef<'gcx> {
                 def_id.hash_stable(hcx, hasher);
                 t.hash_stable(hcx, hasher);
             }
-            ty::InstanceDef::CloneCopyShim(def_id, t) |
+            ty::InstanceDef::CloneCopyShim(def_id) => {
+                def_id.hash_stable(hcx, hasher);
+            }
             ty::InstanceDef::CloneStructuralShim(def_id, t) |
             ty::InstanceDef::CloneNominalShim(def_id, t) => {
                 def_id.hash_stable(hcx, hasher);

src/librustc/ty/instance.rs

@@ -47,7 +47,7 @@ pub enum InstanceDef<'tcx> {
     ///`<T as Clone>::clone` shim for Copy types
     ///
     /// The DefId is the DefId of the Clone::clone function
-    CloneCopyShim(DefId, Ty<'tcx>),
+    CloneCopyShim(DefId),
     ///`<T as Clone>::clone` shim for arrays and tuples
     ///
     /// The DefId is the DefId of the Clone::clone function
@@ -78,7 +78,7 @@ impl<'tcx> InstanceDef<'tcx> {
             InstanceDef::Intrinsic(def_id, ) |
             InstanceDef::ClosureOnceShim { call_once: def_id } |
             InstanceDef::DropGlue(def_id, _) |
-            InstanceDef::CloneCopyShim(def_id, _) |
+            InstanceDef::CloneCopyShim(def_id) |
             InstanceDef::CloneStructuralShim(def_id, _) |
             InstanceDef::CloneNominalShim(def_id, _) => def_id
         }
@@ -146,7 +146,9 @@ impl<'tcx> fmt::Display for Instance<'tcx> {
             InstanceDef::DropGlue(_, ty) => {
                 write!(f, " - shim({:?})", ty)
             }
-            InstanceDef::CloneCopyShim(_, ty) |
+            InstanceDef::CloneCopyShim(def) => {
+                write!(f, " - shim({:?})", def)
+            }
             InstanceDef::CloneStructuralShim(_, ty) |
             InstanceDef::CloneNominalShim(_, ty) => {
                 write!(f, " - shim({:?})", ty)
@@ -311,7 +313,7 @@ fn resolve_associated_item<'a, 'tcx>(
                     let self_ty = trait_ref.self_ty();
                     match self_ty.sty {
                         _ if !self_ty.moves_by_default(tcx, param_env, DUMMY_SP) => {
-                            ty::InstanceDef::CloneCopyShim(def_id, self_ty)
+                            ty::InstanceDef::CloneCopyShim(def_id)
                         }
                         ty::TyArray(..) => ty::InstanceDef::CloneStructuralShim(def_id, self_ty),
                         ty::TyTuple(..) => ty::InstanceDef::CloneStructuralShim(def_id, self_ty),

src/librustc_mir/shim.rs

@@ -99,7 +99,13 @@ fn make_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         ty::InstanceDef::DropGlue(def_id, ty) => {
             build_drop_shim(tcx, def_id, ty)
         }
-        ty::InstanceDef::CloneCopyShim(def_id, ty) |
+        ty::InstanceDef::CloneCopyShim(def_id) => {
+            let substs = Substs::identity_for_item(tcx, def_id);
+            let self_ty = substs.type_at(0);
+            let mut builder = CloneShimBuilder::new(tcx, def_id, self_ty);
+            builder.copy_shim();
+            builder.into_mir()
+        }
         ty::InstanceDef::CloneNominalShim(def_id, ty) |
         ty::InstanceDef::CloneStructuralShim(def_id, ty) => {
             build_clone_shim(tcx, def_id, ty)
@@ -289,13 +295,11 @@ fn build_clone_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     debug!("build_clone_shim(def_id={:?})", def_id);
 
     let mut builder = CloneShimBuilder::new(tcx, def_id, self_ty);
-    let is_copy = !self_ty.moves_by_default(tcx, tcx.param_env(def_id), builder.span);
 
     let dest = Place::Local(RETURN_PLACE);
     let src = Place::Local(Local::new(1+0)).deref();
 
     match self_ty.sty {
-        _ if is_copy => builder.copy_shim(),
         ty::TyArray(ty, len) => {
             let len = len.val.to_const_int().unwrap().to_u64().unwrap();
             builder.array_shim(dest, src, ty, len)