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Author: cfallin

crates/environ/src/gc.rs

@@ -455,7 +455,7 @@ impl GcExceptionLayout {
 /// VMGcKind::EqRef`.
 ///
 /// Furthermore, this type only uses the highest 6 bits of its `u32`
-/// representation, allowing the lower 27 bytes to be bitpacked with other stuff
+/// representation, allowing the lower 26 bits to be bitpacked with other stuff
 /// as users see fit.
 #[repr(u32)]
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]

crates/environ/src/types.rs

@@ -883,7 +883,7 @@ impl TypeTrace for WasmContType {
 /// type-level *signature*. When a particular *exception object* is
 /// created in a store, it can be associated with a particular *tag
 /// instance* also in that store, and the compatibility is checked
-/// (the tag's function type must match teh function type in the
+/// (the tag's function type must match the function type in the
 /// associated WasmExnType).
 #[derive(Debug, Clone, Eq, PartialEq, Hash, Serialize, Deserialize)]
 pub struct WasmExnType {

crates/wasmtime/src/runtime/coredump.rs

@@ -205,9 +205,10 @@ impl WasmCoreDump {
                         wasm_encoder::ConstExpr::ref_null(wasm_encoder::HeapType::ANY)
                     }
                     Val::ExnRef(_) => {
-                        todo!(
-                            "Cannot encode a core dump with an exception object global because the wasm_encoder::HeapType does not exist"
-                        )
+                        wasm_encoder::ConstExpr::ref_null(wasm_encoder::HeapType::Abstract {
+                            shared: false,
+                            ty: wasm_encoder::AbstractHeapType::Exn,
+                        })
                     }
                 };
                 globals.global(

crates/wasmtime/src/runtime/externals/tag.rs

@@ -33,29 +33,7 @@ impl Tag {
     /// When using an async resource limiter, use [`Tag::new_async`]
     /// instead.
     pub fn new(mut store: impl AsContextMut, ty: &TagType) -> Result<Tag> {
-        Tag::_new(store.as_context_mut().0, ty)
-    }
-
-    /// Async variant of [`Tag::new`]. You must use this variant with
-    /// [`Store`](`crate::Store`)s which have a
-    /// [`ResourceLimiterAsync`](`crate::ResourceLimiterAsync`).
-    ///
-    /// # Panics
-    ///
-    /// This function will panic when used with a non-async
-    /// [`Store`](`crate::Store`).
-    #[cfg(feature = "async")]
-    pub async fn new_async(mut store: impl AsContextMut<Data: Send>, ty: &TagType) -> Result<Tag> {
-        let mut store = store.as_context_mut();
-        assert!(
-            store.0.async_support(),
-            "cannot use `new_async` without enabling async support on the config"
-        );
-        store.on_fiber(|store| Tag::_new(store.0, ty)).await?
-    }
-
-    fn _new(store: &mut StoreOpaque, ty: &TagType) -> Result<Tag> {
-        generate_tag_export(store, ty)
+        generate_tag_export(store.as_context_mut().0, ty)
     }
 
     /// Returns the underlying type of this `tag`.

crates/wasmtime/src/runtime/vm/instance.rs

@@ -1004,7 +1004,7 @@ impl Instance {
                             VMGcRef::from_raw_u32(raw.get_externref())
                         }),
                     )?,
-                    WasmHeapTopType::Any => table.init_gc_refs(
+                    WasmHeapTopType::Any | WasmHeapTopType::Exn => table.init_gc_refs(
                         dst,
                         exprs.iter().map(|expr| unsafe {
                             let raw = const_evaluator
@@ -1025,9 +1025,6 @@ impl Instance {
                             )
                         }),
                     )?,
-                    WasmHeapTopType::Exn => {
-                        unreachable!("Cannot initialize exception objects from an element segment")
-                    }
                     WasmHeapTopType::Cont => todo!(), // FIXME: #10248 stack switching support.
                 }
             }