Add test and remove double ref

compiler/rustc_smir/src/rustc_internal/mod.rs

@@ -142,7 +142,7 @@ pub fn crate_num(item: &stable_mir::Crate) -> CrateNum {
 
 pub(crate) fn init<'tcx>(tables: &TablesWrapper<'tcx>, f: impl FnOnce()) {
     assert!(!TLV.is_set());
-    let ptr: *const () = &tables as *const &_ as _;
+    let ptr = tables as *const _ as *const ();
     TLV.set(&Cell::new(ptr), || {
         f();
     });
@@ -155,8 +155,8 @@ pub(crate) fn with_tables<'tcx, R>(f: impl FnOnce(&mut Tables<'tcx>) -> R) -> R
     TLV.with(|tlv| {
         let ptr = tlv.get();
         assert!(!ptr.is_null());
-        let wrapper = unsafe { *(ptr as *const &TablesWrapper<'tcx>) };
-        let mut tables = wrapper.0.borrow_mut();
+        let wrapper = ptr as *const TablesWrapper<'tcx>;
+        let mut tables = unsafe { (*wrapper).0.borrow_mut() };
         f(&mut *tables)
     })
 }

tests/ui-fulldeps/stable-mir/check_instance.rs

@@ -1,5 +1,5 @@
 // run-pass
-// Test that users are able to use stable mir APIs to retrieve monomorphized instances
+//! Test that users are able to use stable mir APIs to retrieve monomorphized instances
 
 // ignore-stage1
 // ignore-cross-compile
@@ -14,15 +14,15 @@
 extern crate rustc_middle;
 #[macro_use]
 extern crate rustc_smir;
-extern crate stable_mir;
 extern crate rustc_driver;
 extern crate rustc_interface;
+extern crate stable_mir;
 
-use rustc_middle::ty::TyCtxt;
 use mir::{mono::Instance, TerminatorKind::*};
-use stable_mir::ty::{TyKind, RigidTy};
-use stable_mir::*;
+use rustc_middle::ty::TyCtxt;
 use rustc_smir::rustc_internal;
+use stable_mir::ty::{RigidTy, TyKind};
+use stable_mir::*;
 use std::io::Write;
 use std::ops::ControlFlow;
 
@@ -33,16 +33,16 @@ fn test_stable_mir(_tcx: TyCtxt<'_>) -> ControlFlow<()> {
     let items = stable_mir::all_local_items();
 
     // Get all items and split generic vs monomorphic items.
-    let (generic, mono) : (Vec<_>, Vec<_>) = items.into_iter().partition(|item| {
-        item.requires_monomorphization()
-    });
+    let (generic, mono): (Vec<_>, Vec<_>) =
+        items.into_iter().partition(|item| item.requires_monomorphization());
     assert_eq!(mono.len(), 3, "Expected 2 mono functions and one constant");
     assert_eq!(generic.len(), 2, "Expected 2 generic functions");
 
     // For all monomorphic items, get the correspondent instances.
-    let instances = mono.iter().filter_map(|item| {
-        mir::mono::Instance::try_from(*item).ok()
-    }).collect::<Vec<mir::mono::Instance>>();
+    let instances = mono
+        .iter()
+        .filter_map(|item| mir::mono::Instance::try_from(*item).ok())
+        .collect::<Vec<mir::mono::Instance>>();
     assert_eq!(instances.len(), mono.len());
 
     // For all generic items, try_from should fail.
@@ -58,19 +58,22 @@ fn test_stable_mir(_tcx: TyCtxt<'_>) -> ControlFlow<()> {
 fn test_body(body: mir::Body) {
     for term in body.blocks.iter().map(|bb| &bb.terminator) {
         match &term.kind {
-            Call{ func, .. } => {
+            Call { func, .. } => {
                 let TyKind::RigidTy(ty) = func.ty(&body.locals).kind() else { unreachable!() };
                 let RigidTy::FnDef(def, args) = ty else { unreachable!() };
                 let result = Instance::resolve(def, &args);
                 assert!(result.is_ok());
             }
-            Goto {..} | Assert{..} | SwitchInt{..} | Return | Drop {..} => { /* Do nothing */}
-            _ => { unreachable!("Unexpected terminator {term:?}") }
+            Goto { .. } | Assert { .. } | SwitchInt { .. } | Return | Drop { .. } => {
+                /* Do nothing */
+            }
+            _ => {
+                unreachable!("Unexpected terminator {term:?}")
+            }
         }
     }
 }
 
-
 /// This test will generate and analyze a dummy crate using the stable mir.
 /// For that, it will first write the dummy crate into a file.
 /// Then it will create a `StableMir` using custom arguments and then

tests/ui-fulldeps/stable-mir/smir_internal.rs

@@ -0,0 +1,64 @@
+// run-pass
+//! Test that users are able to use retrieve internal constructs from stable ones to help with
+//! the migration.
+
+// ignore-stage1
+// ignore-cross-compile
+// ignore-remote
+// ignore-windows-gnu mingw has troubles with linking https://github.com/rust-lang/rust/pull/116837
+// edition: 2021
+
+#![feature(rustc_private)]
+#![feature(assert_matches)]
+#![feature(control_flow_enum)]
+
+#[macro_use]
+extern crate rustc_smir;
+extern crate rustc_driver;
+extern crate rustc_interface;
+extern crate rustc_middle;
+extern crate stable_mir;
+
+use rustc_middle::ty::TyCtxt;
+use rustc_smir::rustc_internal;
+use std::io::Write;
+use std::ops::ControlFlow;
+
+const CRATE_NAME: &str = "input";
+
+fn test_translation(_tcx: TyCtxt<'_>) -> ControlFlow<()> {
+    let main_fn = stable_mir::entry_fn().unwrap();
+    let body = main_fn.body();
+    let orig_ty = body.locals[0].ty;
+    let rustc_ty = rustc_internal::internal(&orig_ty);
+    assert!(rustc_ty.is_unit());
+    ControlFlow::Continue(())
+}
+
+/// This test will generate and analyze a dummy crate using the stable mir.
+/// For that, it will first write the dummy crate into a file.
+/// Then it will create a `StableMir` using custom arguments and then
+/// it will run the compiler.
+fn main() {
+    let path = "internal_input.rs";
+    generate_input(&path).unwrap();
+    let args = vec![
+        "rustc".to_string(),
+        "--crate-name".to_string(),
+        CRATE_NAME.to_string(),
+        path.to_string(),
+    ];
+    run!(args, tcx, test_translation(tcx)).unwrap();
+}
+
+fn generate_input(path: &str) -> std::io::Result<()> {
+    let mut file = std::fs::File::create(path)?;
+    write!(
+        file,
+        r#"
+    pub fn main() {{
+    }}
+    "#
+    )?;
+    Ok(())
+}