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, 5 insertions, 2 deletions

diff --git a/src/passes/LocalCSE.cpp b/src/passes/LocalCSE.cpp
index 0816bf6ea..b49c92310 100644
--- a/src/passes/LocalCSE.cpp
+++ b/src/passes/LocalCSE.cpp
@@ -172,9 +172,12 @@ struct LocalCSE : public WalkerPass<LinearExecutionWalker<LocalCSE>> {
   void handle(Expression* curr) {
     if (auto* set = curr->dynCast<LocalSet>()) {
       // Calculate equivalences
+      auto* func = getFunction();
       equivalences.reset(set->index);
       if (auto* get = set->value->dynCast<LocalGet>()) {
-        equivalences.add(set->index, get->index);
+        if (func->getLocalType(set->index) == func->getLocalType(get->index)) {
+          equivalences.add(set->index, get->index);
+        }
       }
       // consider the value
       auto* value = set->value;
@@ -184,7 +187,7 @@ struct LocalCSE : public WalkerPass<LinearExecutionWalker<LocalCSE>> {
         if (iter != usables.end()) {
           // already exists in the table, this is good to reuse
           auto& info = iter->second;
-          Type localType = getFunction()->getLocalType(info.index);
+          Type localType = func->getLocalType(info.index);
           set->value =
             Builder(*getModule()).makeLocalGet(info.index, localType);
           anotherPass = true;