[Wasm GC] Allow tail call subtyping in DeadArgumentElimination (#4035)

Partially reverts #4025, removing the code and updates the test to show
we do the optimization.

1 files changed, 2 insertions, 8 deletions

diff --git a/src/passes/DeadArgumentElimination.cpp b/src/passes/DeadArgumentElimination.cpp
index 9d8fa5b0d..f3e3ae98c 100644
--- a/src/passes/DeadArgumentElimination.cpp
+++ b/src/passes/DeadArgumentElimination.cpp
@@ -327,14 +327,8 @@ struct DAE : public Pass {
       // affect whether an argument is used or not, it just refines the type
       // where possible.
       refineArgumentTypes(func, calls, module);
-      // Refine return types as well, if we can. We cannot do so if this
-      // function is tail-called, because then the return type must match that
-      // of the function doing a tail call of it - we cannot change just one of
-      // them.
-      //
-      // TODO: Try to optimize in a more holistic manner, see the TODO in
-      //       refineReturnTypes() about missing a global optimum.
-      if (!tailCallees.count(name) && refineReturnTypes(func, calls, module)) {
+      // Refine return types as well.
+      if (refineReturnTypes(func, calls, module)) {
         refinedReturnTypes = true;
       }
       // Check if all calls pass the same constant for a particular argument.