1 files changed, 60 insertions, 0 deletions
diff --git a/src/passes/NoExitRuntime.cpp b/src/passes/NoExitRuntime.cpp
new file mode 100644
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--- /dev/null
+++ b/src/passes/NoExitRuntime.cpp
@@ -0,0 +1,60 @@
+/*
+ * Copyright 2016 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.
+ */
+
+//
+// Assumes the program will never exit the runtime (as in the emscripten
+// NO_EXIT_RUNTIME option). That means that atexit()s do not need to be
+// run.
+//
+
+#include <pass.h>
+#include <wasm.h>
+#include <wasm-builder.h>
+#include <asmjs/shared-constants.h>
+
+using namespace std;
+
+namespace wasm {
+
+struct NoExitRuntime : public WalkerPass<PostWalker<NoExitRuntime>> {
+  bool isFunctionParallel() override { return true; }
+
+  Pass* create() override { return new NoExitRuntime; }
+
+  void visitCall(Call* curr) {
+    auto* import = getModule()->getFunctionOrNull(curr->target);
+    if (!import || !import->imported() || import->module != ENV) return;
+    // Remove all possible manifestations of atexit, across asm2wasm and llvm wasm backend.
+    for (auto* name : {
+      "___cxa_atexit",
+      "_atexit",
+      "__cxa_atexit",
+      "atexit",
+    }) {
+      if (strcmp(name, import->base.str) == 0) {
+        replaceCurrent(
+          Builder(*getModule()).replaceWithIdenticalType(curr)
+        );
+      }
+    }
+  }
+};
+
+Pass* createNoExitRuntimePass() {
+  return new NoExitRuntime();
+}
+
+} // namespace wasm