Unify imported and non-imported things (#1678)

Fixes #1649

This moves us to a single object for functions, which can be imported or nor, and likewise for globals (as a result, GetGlobals do not need to check if the global is imported or not, etc.). All imported things now inherit from Importable, which has the module and base of the import, and if they are set then it is an import.

For convenient iteration, there are a few helpers like

ModuleUtils::iterDefinedGlobals(wasm, [&](Global* global) {
  .. use global ..
});

as often iteration only cares about imported or defined (non-imported) things.

1 files changed, 4 insertions, 1 deletions

diff --git a/src/ir/function-utils.h b/src/ir/function-utils.h
index 317b2f1b1..3895b33bf 100644
--- a/src/ir/function-utils.h
+++ b/src/ir/function-utils.h
@@ -35,7 +35,10 @@ inline bool equal(Function* left, Function* right) {
   }
   if (left->result != right->result) return false;
   if (left->type != right->type) return false;
-  return ExpressionAnalyzer::equal(left->body, right->body);
+  if (!left->imported() && !right->imported()) {
+    return ExpressionAnalyzer::equal(left->body, right->body);
+  }
+  return left->imported() && right->imported();
 }
 
 } // namespace FunctionUtils