PR updates

Author: stevenfontanella

src/passes/GlobalEffects.cpp

@@ -48,21 +48,30 @@ struct FuncInfo {
   std::unordered_set<HeapType> indirectCalledTypes;
 };
 
+/*
+ Only funcs that are 'addressed' may be the target of an indirect call. A
+ function is addressed if:
+ - It appears in a ref.func expression
+ - It appears in an `elem declare` statement (note that we already ignore `elem`
+   statements in our IR, but we check separately for funcs that appear in
+ `ref.func`).
+ - It's exported, because it may flow back to us as a reference.
+ - It's imported, which implies it is `elem declare`d.
+
+ If a function doesn't meet any of these criteria, it can't be the target of
+ an indirect call and we don't need to include its effects in indirect calls.
+*/
 std::unordered_set<Function*> getAddressedFuncs(Module& module) {
-  struct AddressedFuncsWalker
-    : PostWalker<AddressedFuncsWalker,
-                 UnifiedExpressionVisitor<AddressedFuncsWalker>> {
+  struct AddressedFuncsWalker : PostWalker<AddressedFuncsWalker> {
     const Module& module;
     std::unordered_set<Function*>& addressedFuncs;
 
     AddressedFuncsWalker(const Module& module,
                          std::unordered_set<Function*>& addressedFuncs)
       : module(module), addressedFuncs(addressedFuncs) {}
 
-    void visitExpression(Expression* curr) {
-      if (auto* refFunc = curr->dynCast<RefFunc>()) {
-        addressedFuncs.insert(module.getFunction(refFunc->func));
-      }
+    void visitRefFunc(RefFunc* refFunc) {
+      addressedFuncs.insert(module.getFunction(refFunc->func));
     }
   };
 
@@ -80,9 +89,6 @@ std::unordered_set<Function*> getAddressedFuncs(Module& module) {
       continue;
     }
 
-    // TODO: internal or external? I think internal
-    // This might be why we failed to lookup the function earlier
-    // Maybe we can use Function* after all
     addressedFuncs.insert(module.getFunction(*export_->getInternalName()));
   }
 
@@ -199,7 +205,7 @@ using CallGraph =
 
 CallGraph buildCallGraph(const Module& module,
                          const std::map<Function*, FuncInfo>& funcInfos,
-                         const std::unordered_set<Function*> addressedFuncs,
+                         const std::unordered_set<Function*>& addressedFuncs,
                          bool closedWorld) {
   CallGraph callGraph;
   if (!closedWorld) {