diff --git a/compiler/rustc_codegen_cranelift/src/lib.rs b/compiler/rustc_codegen_cranelift/src/lib.rs
index fae71fef9e676..8edb883ccb5f9 100644
--- a/compiler/rustc_codegen_cranelift/src/lib.rs
+++ b/compiler/rustc_codegen_cranelift/src/lib.rs
@@ -11,7 +11,6 @@
 #![warn(rust_2018_idioms)]
 #![warn(unused_lifetimes)]
 #![warn(unreachable_pub)]
-#![feature(box_patterns)]
 
 extern crate snap;
 #[macro_use]
diff --git a/compiler/rustc_mir/src/borrow_check/mod.rs b/compiler/rustc_mir/src/borrow_check/mod.rs
index 8683318e4a7b5..5b8bb7257e230 100644
--- a/compiler/rustc_mir/src/borrow_check/mod.rs
+++ b/compiler/rustc_mir/src/borrow_check/mod.rs
@@ -629,18 +629,11 @@ impl<'cx, 'tcx> dataflow::ResultsVisitor<'cx, 'tcx> for MirBorrowckCtxt<'cx, 'tc
 
             StatementKind::CopyNonOverlapping(box rustc_middle::mir::CopyNonOverlapping {
                 ..
-                /*
-                src,
-                dst,
-                count,
-                */
             }) => {
-                unreachable!()
-                /*
-                self.consume_operand(location, (src, span), flow_state);
-                self.consume_operand(location, (dst, span), flow_state);
-                self.consume_operand(location, (count, span), flow_state);
-                */
+                span_bug!(
+                    span,
+                    "Unexpected CopyNonOverlapping, should only appear after lower_intrinsics",
+                )
             }
             StatementKind::Nop
             | StatementKind::Coverage(..)
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/mod.rs b/compiler/rustc_mir/src/borrow_check/type_check/mod.rs
index 58db2752c9845..ab7e75bf4f10c 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/mod.rs
+++ b/compiler/rustc_mir/src/borrow_check/type_check/mod.rs
@@ -1521,40 +1521,11 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 }
             }
             StatementKind::CopyNonOverlapping(box rustc_middle::mir::CopyNonOverlapping {
-                ref src,
-                ref dst,
-                ref count,
-            }) => {
-                let op_src_ty = self.normalize(src.ty(body, self.tcx()), location);
-                let op_dst_ty = self.normalize(dst.ty(body, self.tcx()), location);
-                // since CopyNonOverlapping is parametrized by 1 type,
-                // we only need to check that they are equal and not keep an extra parameter.
-                if let Err(terr) = self.eq_types(
-                    op_src_ty,
-                    op_dst_ty,
-                    location.to_locations(),
-                    ConstraintCategory::Internal,
-                ) {
-                    span_mirbug!(
-                        self,
-                        stmt,
-                        "bad arg ({:?} != {:?}): {:?}",
-                        op_src_ty,
-                        op_dst_ty,
-                        terr
-                    );
-                }
-
-                let op_cnt_ty = self.normalize(count.ty(body, self.tcx()), location);
-                if let Err(terr) = self.eq_types(
-                    op_cnt_ty,
-                    tcx.types.usize,
-                    location.to_locations(),
-                    ConstraintCategory::Internal,
-                ) {
-                    span_mirbug!(self, stmt, "bad arg ({:?} != usize): {:?}", op_cnt_ty, terr);
-                }
-            }
+                ..
+            }) => span_bug!(
+                stmt.source_info.span,
+                "Unexpected StatementKind::CopyNonOverlapping, should only appear after lowering_intrinsics",
+            ),
             StatementKind::FakeRead(..)
             | StatementKind::StorageLive(..)
             | StatementKind::StorageDead(..)
diff --git a/compiler/rustc_mir/src/dataflow/impls/borrows.rs b/compiler/rustc_mir/src/dataflow/impls/borrows.rs
index ffa02f855c979..f24d0f0266d9f 100644
--- a/compiler/rustc_mir/src/dataflow/impls/borrows.rs
+++ b/compiler/rustc_mir/src/dataflow/impls/borrows.rs
@@ -305,9 +305,8 @@ impl<'tcx> dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
             | mir::StatementKind::Retag { .. }
             | mir::StatementKind::AscribeUserType(..)
             | mir::StatementKind::Coverage(..)
+            | mir::StatementKind::CopyNonOverlapping(..)
             | mir::StatementKind::Nop => {}
-
-            mir::StatementKind::CopyNonOverlapping(..) => todo!(),
         }
     }
 
diff --git a/compiler/rustc_mir/src/dataflow/impls/storage_liveness.rs b/compiler/rustc_mir/src/dataflow/impls/storage_liveness.rs
index e407f394c51ec..792664597fd9a 100644
--- a/compiler/rustc_mir/src/dataflow/impls/storage_liveness.rs
+++ b/compiler/rustc_mir/src/dataflow/impls/storage_liveness.rs
@@ -149,9 +149,8 @@ impl<'mir, 'tcx> dataflow::GenKillAnalysis<'tcx> for MaybeRequiresStorage<'mir,
             | StatementKind::FakeRead(..)
             | StatementKind::Nop
             | StatementKind::Retag(..)
+            | StatementKind::CopyNonOverlapping(..)
             | StatementKind::StorageLive(..) => {}
-
-            StatementKind::CopyNonOverlapping(..) => todo!(),
         }
     }
 
diff --git a/compiler/rustc_mir/src/dataflow/move_paths/builder.rs b/compiler/rustc_mir/src/dataflow/move_paths/builder.rs
index c14ac74ebadab..1ddd81e779b15 100644
--- a/compiler/rustc_mir/src/dataflow/move_paths/builder.rs
+++ b/compiler/rustc_mir/src/dataflow/move_paths/builder.rs
@@ -318,9 +318,8 @@ impl<'b, 'a, 'tcx> Gatherer<'b, 'a, 'tcx> {
             StatementKind::Retag { .. }
             | StatementKind::AscribeUserType(..)
             | StatementKind::Coverage(..)
+            | StatementKind::CopyNonOverlapping(..)
             | StatementKind::Nop => {}
-
-            StatementKind::CopyNonOverlapping(..) => todo!(),
         }
     }
 
diff --git a/compiler/rustc_mir/src/interpret/intrinsics.rs b/compiler/rustc_mir/src/interpret/intrinsics.rs
index b0a2d906519ac..25c3c2c632d81 100644
--- a/compiler/rustc_mir/src/interpret/intrinsics.rs
+++ b/compiler/rustc_mir/src/interpret/intrinsics.rs
@@ -323,26 +323,8 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 let result = Scalar::from_uint(truncated_bits, layout.size);
                 self.write_scalar(result, dest)?;
             }
-            sym::copy_nonoverlapping => {
-                self.copy_nonoverlapping(args[0], args[1], args[2])?;
-            }
             sym::copy => {
-                let elem_ty = instance.substs.type_at(0);
-                let elem_layout = self.layout_of(elem_ty)?;
-                let count = self.read_scalar(&args[2])?.to_machine_usize(self)?;
-                let elem_align = elem_layout.align.abi;
-
-                let size = elem_layout.size.checked_mul(count, self).ok_or_else(|| {
-                    err_ub_format!("overflow computing total size of `{}`", intrinsic_name)
-                })?;
-                let src = self.read_scalar(&args[0])?.check_init()?;
-                let src = self.memory.check_ptr_access(src, size, elem_align)?;
-                let dest = self.read_scalar(&args[1])?.check_init()?;
-                let dest = self.memory.check_ptr_access(dest, size, elem_align)?;
-
-                if let (Some(src), Some(dest)) = (src, dest) {
-                    self.memory.copy(src, dest, size, false)?;
-                }
+                self.copy(&args[0], &args[1], &args[2], /*nonoverlapping*/ false)?;
             }
             sym::offset => {
                 let ptr = self.read_scalar(&args[0])?.check_init()?;
diff --git a/compiler/rustc_mir/src/interpret/step.rs b/compiler/rustc_mir/src/interpret/step.rs
index 1c2bc57c99a83..0f365eaa41dde 100644
--- a/compiler/rustc_mir/src/interpret/step.rs
+++ b/compiler/rustc_mir/src/interpret/step.rs
@@ -120,7 +120,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
                 let src = self.eval_operand(src, None)?;
                 let dst = self.eval_operand(dst, None)?;
-                self.copy_nonoverlapping(src, dst, count)?;
+                self.copy(&src, &dst, &count, /* nonoverlapping */ true)?;
             }
 
             // Statements we do not track.
@@ -150,11 +150,12 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         Ok(())
     }
 
-    pub(crate) fn copy_nonoverlapping(
+    pub(crate) fn copy(
         &mut self,
-        src: OpTy<'tcx, <M as Machine<'mir, 'tcx>>::PointerTag>,
-        dst: OpTy<'tcx, <M as Machine<'mir, 'tcx>>::PointerTag>,
-        count: OpTy<'tcx, <M as Machine<'mir, 'tcx>>::PointerTag>,
+        src: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::PointerTag>,
+        dst: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::PointerTag>,
+        count: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::PointerTag>,
+        nonoverlapping: bool,
     ) -> InterpResult<'tcx> {
         let count = self.read_scalar(&count)?.to_machine_usize(self)?;
         let layout = self.layout_of(src.layout.ty.builtin_deref(true).unwrap().ty)?;
@@ -170,7 +171,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         })?;
 
         if let (Some(src), Some(dst)) = (src, dst) {
-            self.memory.copy(src, dst, size, /*nonoverlapping*/ true)?;
+            self.memory.copy(src, dst, size, nonoverlapping)?;
         }
         Ok(())
     }
diff --git a/compiler/rustc_mir/src/transform/validate.rs b/compiler/rustc_mir/src/transform/validate.rs
index 29b90bff210bd..d009b0b1b2384 100644
--- a/compiler/rustc_mir/src/transform/validate.rs
+++ b/compiler/rustc_mir/src/transform/validate.rs
@@ -294,7 +294,49 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                     );
                 }
             }
-            _ => {}
+            StatementKind::CopyNonOverlapping(box rustc_middle::mir::CopyNonOverlapping {
+                ref src,
+                ref dst,
+                ref count,
+            }) => {
+                let src_ty = src.ty(&self.body.local_decls, self.tcx);
+                let op_src_ty = if let Some(src_deref) = src_ty.builtin_deref(true) {
+                    src_deref.ty
+                } else {
+                    self.fail(
+                        location,
+                        format!("Expected src to be ptr in copy_nonoverlapping, got: {}", src_ty),
+                    );
+                    return;
+                };
+                let dst_ty = dst.ty(&self.body.local_decls, self.tcx);
+                let op_dst_ty = if let Some(dst_deref) = dst_ty.builtin_deref(true) {
+                    dst_deref.ty
+                } else {
+                    self.fail(
+                        location,
+                        format!("Expected dst to be ptr in copy_nonoverlapping, got: {}", dst_ty),
+                    );
+                    return;
+                };
+                // since CopyNonOverlapping is parametrized by 1 type,
+                // we only need to check that they are equal and not keep an extra parameter.
+                if op_src_ty != op_dst_ty {
+                    self.fail(location, format!("bad arg ({:?} != {:?})", op_src_ty, op_dst_ty));
+                }
+
+                let op_cnt_ty = count.ty(&self.body.local_decls, self.tcx);
+                if op_cnt_ty != self.tcx.types.usize {
+                    self.fail(location, format!("bad arg ({:?} != usize)", op_cnt_ty))
+                }
+            }
+            StatementKind::SetDiscriminant { .. }
+            | StatementKind::StorageLive(..)
+            | StatementKind::StorageDead(..)
+            | StatementKind::LlvmInlineAsm(..)
+            | StatementKind::Retag(_, _)
+            | StatementKind::Coverage(_)
+            | StatementKind::Nop => {}
         }
 
         self.super_statement(statement, location);