[Wasm GC] Fix CFG traversal of call_ref and add missing validation check (#4690)

We were missing CallRef in the CFG traversal code in a place where we
note possible exceptions. As a result we thought CallRef cannot throw, and
were missing some control flow edges.

To actually detect the problem, we need to validate non-nullable locals
properly, which we were not doing. This adds that as well.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/cfg/cfg-traversal.h b/src/cfg/cfg-traversal.h
index faaa3c830..478b4780e 100644
--- a/src/cfg/cfg-traversal.h
+++ b/src/cfg/cfg-traversal.h
@@ -392,7 +392,8 @@ struct CFGWalker : public ControlFlowWalker<SubType, VisitorType> {
         break;
       }
       case Expression::Id::CallId:
-      case Expression::Id::CallIndirectId: {
+      case Expression::Id::CallIndirectId:
+      case Expression::Id::CallRefId: {
         self->pushTask(SubType::doEndCall, currp);
         break;
       }