Add support for reference types proposal (#2451)

This adds support for the reference type proposal. This includes support
for all reference types (`anyref`, `funcref`(=`anyfunc`), and `nullref`)
and four new instructions: `ref.null`, `ref.is_null`, `ref.func`, and
new typed `select`. This also adds subtype relationship support between
reference types.

This does not include table instructions yet. This also does not include
wasm2js support.

Fixes #2444 and fixes #2447.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/ir/utils.h b/src/ir/utils.h
index cad7bc885..9bd3c9e0b 100644
--- a/src/ir/utils.h
+++ b/src/ir/utils.h
@@ -146,6 +146,9 @@ struct ReFinalize
   void visitDrop(Drop* curr);
   void visitReturn(Return* curr);
   void visitHost(Host* curr);
+  void visitRefNull(RefNull* curr);
+  void visitRefIsNull(RefIsNull* curr);
+  void visitRefFunc(RefFunc* curr);
   void visitTry(Try* curr);
   void visitThrow(Throw* curr);
   void visitRethrow(Rethrow* curr);
@@ -210,6 +213,9 @@ struct ReFinalizeNode : public OverriddenVisitor<ReFinalizeNode> {
   void visitDrop(Drop* curr) { curr->finalize(); }
   void visitReturn(Return* curr) { curr->finalize(); }
   void visitHost(Host* curr) { curr->finalize(); }
+  void visitRefNull(RefNull* curr) { curr->finalize(); }
+  void visitRefIsNull(RefIsNull* curr) { curr->finalize(); }
+  void visitRefFunc(RefFunc* curr) { curr->finalize(); }
   void visitTry(Try* curr) { curr->finalize(); }
   void visitThrow(Throw* curr) { curr->finalize(); }
   void visitRethrow(Rethrow* curr) { curr->finalize(); }