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diff --git a/src/utils/bit_mask_set.h b/src/utils/bit_mask_set.h
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+/*
+ * Copyright 2019 The libgav1 Authors
+ *
+ * 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 LIBGAV1_SRC_UTILS_BIT_MASK_SET_H_
+#define LIBGAV1_SRC_UTILS_BIT_MASK_SET_H_
+
+#include <cstdint>
+
+namespace libgav1 {
+
+// This class is used to check if a given value is equal to one of the several
+// predetermined values using a bit mask instead of a chain of comparisons and
+// ||s. This usually results in fewer instructions.
+//
+// Usage:
+//   constexpr BitMaskSet set(value1, value2);
+//   set.Contains(value1) => returns true.
+//   set.Contains(value3) => returns false.
+class BitMaskSet {
+ public:
+  explicit constexpr BitMaskSet(uint32_t mask) : mask_(mask) {}
+
+  constexpr BitMaskSet(int v1, int v2) : mask_((1U << v1) | (1U << v2)) {}
+
+  constexpr BitMaskSet(int v1, int v2, int v3)
+      : mask_((1U << v1) | (1U << v2) | (1U << v3)) {}
+
+  constexpr BitMaskSet(int v1, int v2, int v3, int v4)
+      : mask_((1U << v1) | (1U << v2) | (1U << v3) | (1U << v4)) {}
+
+  constexpr BitMaskSet(int v1, int v2, int v3, int v4, int v5)
+      : mask_((1U << v1) | (1U << v2) | (1U << v3) | (1U << v4) | (1U << v5)) {}
+
+  constexpr BitMaskSet(int v1, int v2, int v3, int v4, int v5, int v6)
+      : mask_((1U << v1) | (1U << v2) | (1U << v3) | (1U << v4) | (1U << v5) |
+              (1U << v6)) {}
+
+  constexpr BitMaskSet(int v1, int v2, int v3, int v4, int v5, int v6, int v7)
+      : mask_((1U << v1) | (1U << v2) | (1U << v3) | (1U << v4) | (1U << v5) |
+              (1U << v6) | (1U << v7)) {}
+
+  constexpr BitMaskSet(int v1, int v2, int v3, int v4, int v5, int v6, int v7,
+                       int v8, int v9)
+      : mask_((1U << v1) | (1U << v2) | (1U << v3) | (1U << v4) | (1U << v5) |
+              (1U << v6) | (1U << v7) | (1U << v8) | (1U << v9)) {}
+
+  constexpr BitMaskSet(int v1, int v2, int v3, int v4, int v5, int v6, int v7,
+                       int v8, int v9, int v10)
+      : mask_((1U << v1) | (1U << v2) | (1U << v3) | (1U << v4) | (1U << v5) |
+              (1U << v6) | (1U << v7) | (1U << v8) | (1U << v9) | (1U << v10)) {
+  }
+
+  constexpr bool Contains(uint8_t value) const {
+    return MaskContainsValue(mask_, value);
+  }
+
+  static constexpr bool MaskContainsValue(uint32_t mask, uint8_t value) {
+    return ((mask >> value) & 1) != 0;
+  }
+
+ private:
+  const uint32_t mask_;
+};
+
+}  // namespace libgav1
+#endif  // LIBGAV1_SRC_UTILS_BIT_MASK_SET_H_