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+/*
+ * Copyright 2015 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.
+ */
+
+//
+// Removes branches that go to where they go anyhow
+//
+
+#include <wasm.h>
+#include <pass.h>
+
+namespace wasm {
+
+struct RemoveUnusedBrs : public Pass {
+ void visitBlock(Block *curr) override {
+ if (curr->name.isNull()) return;
+ if (curr->list.size() == 0) return;
+ Break* last = curr->list.back()->dyn_cast<Break>();
+ if (!last) return;
+ if (last->value) return;
+ if (last->name == curr->name) {
+ curr->list.pop_back();
+ }
+ }
+};
+
+static RegisterPass<RemoveUnusedBrs> registerPass("remove-unused-brs", "removes breaks from locations that are never branched to");
+
+} // namespace wasm