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diff --git a/src/wasm-features.h b/src/wasm-features.h
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+++ b/src/wasm-features.h
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+/*
+ * Copyright 2019 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_features_h
+#define wasm_features_h
+
+#include <stdint.h>
+
+struct FeatureSet {
+  enum Feature : uint32_t {
+    MVP = 0,
+    Atomics = 1 << 0,
+    MutableGlobals = 1 << 1,
+    TruncSat = 1 << 2,
+    SIMD = 1 << 3,
+    BulkMemory = 1 << 4,
+    SignExt = 1 << 5,
+    All = Atomics | MutableGlobals | TruncSat | SIMD | BulkMemory | SignExt
+  };
+
+  FeatureSet() : features(MVP) {}
+  FeatureSet(uint32_t features) : features(features) {}
+
+  bool isMVP() const { return features == MVP; }
+  bool has(Feature f) { return (features & f) == f; }
+  bool hasAtomics() const { return features & Atomics; }
+  bool hasMutableGlobals() const { return features & MutableGlobals; }
+  bool hasTruncSat() const { return features & TruncSat; }
+  bool hasSIMD() const { return features & SIMD; }
+  bool hasBulkMemory() const { return features & BulkMemory; }
+  bool hasSignExt() const { return features & SignExt; }
+  bool hasAll() const { return features & All; }
+
+  void makeMVP() { features = MVP; }
+  void set(Feature f, bool v = true) { features = v ? (features | f) : (features & ~f); }
+  void setAtomics(bool v = true) { set(Atomics, v); }
+  void setMutableGlobals(bool v = true) { set(MutableGlobals, v); }
+  void setTruncSat(bool v = true) { set(TruncSat, v); }
+  void setSIMD(bool v = true) { set(SIMD, v); }
+  void setBulkMemory(bool v = true) { set(BulkMemory, v); }
+  void setSignExt(bool v = true) { set(SignExt, v); }
+  void setAll(bool v = true) { features = v ? All : MVP; }
+
+  bool operator<=(const FeatureSet& other) {
+    return !(features & ~other.features);
+  }
+
+  FeatureSet& operator|=(const FeatureSet& other) {
+    features |= other.features;
+    return *this;
+  }
+
+private:
+  uint32_t features;
+};
+
+#endif // wasm_features_h