Add anyref feature and type (#3109)

Adds `anyref` type, which is enabled by a new feature `--enable-anyref`. This type is primarily used for testing that passes correctly handle subtype relationships so that the codebase will continue to be prepared for future subtyping. Since `--enable-anyref` is meaningless without also using `--enable-reference-types`, this PR also makes it a validation error to pass only the former (and similarly makes it a validation error to enable exception handling without enabling reference types).

1 files changed, 16 insertions, 17 deletions

diff --git a/test/passes/simplify-locals_all-features_disable-exception-handling.wast b/test/passes/simplify-locals_all-features_disable-exception-handling.wast
index c0f279cd0..f9806641c 100644
--- a/test/passes/simplify-locals_all-features_disable-exception-handling.wast
+++ b/test/passes/simplify-locals_all-features_disable-exception-handling.wast
@@ -1655,20 +1655,19 @@
   )
  )
 )
-;; TODO (GC)
-;; (module
-;;  (func $subtype-test (result anyref)
-;;   (local $0 funcref)
-;;   (local $1 anyref)
-;;   (local $2 anyref)
-;;   (block
-;;    (local.set $1
-;;     (local.get $0)
-;;    )
-;;   )
-;;   (local.set $2
-;;    (local.get $1)
-;;   )
-;;   (local.get $1)
-;;  )
-;; )
+(module
+ (func $subtype-test (result anyref)
+  (local $0 funcref)
+  (local $1 anyref)
+  (local $2 anyref)
+  (block
+   (local.set $1
+    (local.get $0)
+   )
+  )
+  (local.set $2
+   (local.get $1)
+  )
+  (local.get $1)
+ )
+)