Rollup merge of #107706 - tgross35:atomic-as-mut-ptr, r=m-ou-se

[rust.git] / compiler / rustc_abi / src / lib.rs

diff --git a/compiler/rustc_abi/src/lib.rs b/compiler/rustc_abi/src/lib.rs
index fe65ad9c6cb0e9bde1aaff6e4801ef2f2b8c964a..0306cb5ce6abd7615d068c093cff045333e2e26b 100644 (file)
--- a/compiler/rustc_abi/src/lib.rs
+++ b/compiler/rustc_abi/src/lib.rs
@@ -1439,23 +1439,16 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
 pub enum PointerKind {
-    /// Most general case, we know no restrictions to tell LLVM.
-    SharedMutable,
-
-    /// `&T` where `T` contains no `UnsafeCell`, is `dereferenceable`, `noalias` and `readonly`.
-    Frozen,
-
-    /// `&mut T` which is `dereferenceable` and `noalias` but not `readonly`.
-    UniqueBorrowed,
-
-    /// `&mut !Unpin`, which is `dereferenceable` but neither `noalias` nor `readonly`.
-    UniqueBorrowedPinned,
-
-    /// `Box<T>`, which is `noalias` (even on return types, unlike the above) but neither `readonly`
-    /// nor `dereferenceable`.
-    UniqueOwned,
+    /// Shared reference. `frozen` indicates the absence of any `UnsafeCell`.
+    SharedRef { frozen: bool },
+    /// Mutable reference. `unpin` indicates the absence of any pinned data.
+    MutableRef { unpin: bool },
+    /// Box. `unpin` indicates the absence of any pinned data.
+    Box { unpin: bool },
 }
 
+/// Note that this information is advisory only, and backends are free to ignore it.
+/// It can only be used to encode potential optimizations, but no critical information.
 #[derive(Copy, Clone, Debug)]
 pub struct PointeeInfo {
     pub size: Size,