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diff --git a/src/ast/global-utils.h b/src/ast/global-utils.h
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+/*
+ * Copyright 2017 WebAssembly Community Group participants
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef wasm_ast_global_h
+#define wasm_ast_global_h
+
+#include <algorithm>
+#include <vector>
+
+#include "literal.h"
+#include "wasm.h"
+
+namespace wasm {
+
+namespace GlobalUtils {
+  // find a global initialized to the value of an import, or null if no such global
+  inline Global* getGlobalInitializedToImport(Module&wasm, Name module, Name base) {
+    // find the import
+    Name imported;
+    for (auto& import : wasm.imports) {
+      if (import->module == module && import->base == base) {
+        imported = import->name;
+        break;
+      }
+    }
+    if (imported.isNull()) return nullptr;
+    // find a global inited to it
+    for (auto& global : wasm.globals) {
+      if (auto* init = global->init->dynCast<GetGlobal>()) {
+        if (init->name == imported) {
+          return global.get();
+        }
+      }
+    }
+    return nullptr;
+  }
+};
+
+} // namespace wasm
+
+#endif // wasm_ast_global_h
+