Rollup merge of #133732 - nnethercote:fix-Z-dump-mir-dataflow, r=compiler-errors

Fix `-Zdump-mir-dataflow`

r? `@cjgillot`

5 files changed, 7 insertions, 21 deletions

diff --git a/compiler/rustc_mir_dataflow/src/framework/cursor.rs b/compiler/rustc_mir_dataflow/src/framework/cursor.rs
index 11cf8c3e898..4a9bcdaddb3 100644
--- a/compiler/rustc_mir_dataflow/src/framework/cursor.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/cursor.rs
@@ -15,7 +15,6 @@ pub enum ResultsHandle<'a, 'tcx, A>
 where
     A: Analysis<'tcx>,
 {
-    Borrowed(&'a Results<'tcx, A>),
     BorrowedMut(&'a mut Results<'tcx, A>),
     Owned(Results<'tcx, A>),
 }
@@ -28,7 +27,6 @@ where
 
     fn deref(&self) -> &Results<'tcx, A> {
         match self {
-            ResultsHandle::Borrowed(borrowed) => borrowed,
             ResultsHandle::BorrowedMut(borrowed) => borrowed,
             ResultsHandle::Owned(owned) => owned,
         }
@@ -41,9 +39,6 @@ where
 {
     fn deref_mut(&mut self) -> &mut Results<'tcx, A> {
         match self {
-            ResultsHandle::Borrowed(_borrowed) => {
-                panic!("tried to deref_mut a `ResultsHandle::Borrowed")
-            }
             ResultsHandle::BorrowedMut(borrowed) => borrowed,
             ResultsHandle::Owned(owned) => owned,
         }
diff --git a/compiler/rustc_mir_dataflow/src/framework/graphviz.rs b/compiler/rustc_mir_dataflow/src/framework/graphviz.rs
index 6e4994af8b4..561229cf725 100644
--- a/compiler/rustc_mir_dataflow/src/framework/graphviz.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/graphviz.rs
@@ -47,7 +47,7 @@ where
 {
     pub(crate) fn new(
         body: &'mir Body<'tcx>,
-        results: &'mir Results<'tcx, A>,
+        results: &'mir mut Results<'tcx, A>,
         style: OutputStyle,
     ) -> Self {
         let reachable = mir::traversal::reachable_as_bitset(body);
diff --git a/compiler/rustc_mir_dataflow/src/framework/mod.rs b/compiler/rustc_mir_dataflow/src/framework/mod.rs
index f1ea94e1689..b9407882ec5 100644
--- a/compiler/rustc_mir_dataflow/src/framework/mod.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/mod.rs
@@ -281,10 +281,10 @@ pub trait Analysis<'tcx> {
             );
         }
 
-        let results = Results { analysis: self, entry_sets };
+        let mut results = Results { analysis: self, entry_sets };
 
         if tcx.sess.opts.unstable_opts.dump_mir_dataflow {
-            let res = write_graphviz_results(tcx, body, &results, pass_name);
+            let res = write_graphviz_results(tcx, body, &mut results, pass_name);
             if let Err(e) = res {
                 error!("Failed to write graphviz dataflow results: {}", e);
             }
diff --git a/compiler/rustc_mir_dataflow/src/framework/results.rs b/compiler/rustc_mir_dataflow/src/framework/results.rs
index 8493a7aa44b..c4321c454e6 100644
--- a/compiler/rustc_mir_dataflow/src/framework/results.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/results.rs
@@ -37,18 +37,9 @@ impl<'tcx, A> Results<'tcx, A>
 where
     A: Analysis<'tcx>,
 {
-    /// Creates a `ResultsCursor` that can inspect these `Results`. Immutably borrows the `Results`,
-    /// which is appropriate when the `Results` is used outside the cursor.
+    /// Creates a `ResultsCursor` that mutably borrows the `Results`, which is appropriate when the
+    /// `Results` is also used outside the cursor.
     pub fn as_results_cursor<'mir>(
-        &'mir self,
-        body: &'mir mir::Body<'tcx>,
-    ) -> ResultsCursor<'mir, 'tcx, A> {
-        ResultsCursor::new(body, ResultsHandle::Borrowed(self))
-    }
-
-    /// Creates a `ResultsCursor` that can mutate these `Results`. Mutably borrows the `Results`,
-    /// which is appropriate when the `Results` is used outside the cursor.
-    pub fn as_results_cursor_mut<'mir>(
         &'mir mut self,
         body: &'mir mir::Body<'tcx>,
     ) -> ResultsCursor<'mir, 'tcx, A> {
@@ -95,7 +86,7 @@ where
 pub(super) fn write_graphviz_results<'tcx, A>(
     tcx: TyCtxt<'tcx>,
     body: &mir::Body<'tcx>,
-    results: &Results<'tcx, A>,
+    results: &mut Results<'tcx, A>,
     pass_name: Option<&'static str>,
 ) -> std::io::Result<()>
 where
diff --git a/compiler/rustc_mir_transform/src/coroutine.rs b/compiler/rustc_mir_transform/src/coroutine.rs
index 9b9aeccf890..858752a3f01 100644
--- a/compiler/rustc_mir_transform/src/coroutine.rs
+++ b/compiler/rustc_mir_transform/src/coroutine.rs
@@ -680,7 +680,7 @@ fn locals_live_across_suspend_points<'tcx>(
     let mut requires_storage_results =
         MaybeRequiresStorage::new(borrowed_locals_results.into_results_cursor(body))
             .iterate_to_fixpoint(tcx, body, None);
-    let mut requires_storage_cursor = requires_storage_results.as_results_cursor_mut(body);
+    let mut requires_storage_cursor = requires_storage_results.as_results_cursor(body);
 
     // Calculate the liveness of MIR locals ignoring borrows.
     let mut liveness =