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+/*
+ * Copyright 2023 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_analysis_lattices_inverted_h
+#define wasm_analysis_lattices_inverted_h
+
+#include <utility>
+
+#include "../lattice.h"
+
+namespace wasm::analysis {
+
+// Reverses the order of an arbitrary full lattice. For example,
+// `Inverted<UInt32>` would order uint32_t values by > rather than by <.
+template<FullLattice L> struct Inverted {
+  using Element = typename L::Element;
+
+  L lattice;
+  Inverted(L&& lattice) : lattice(std::move(lattice)) {}
+
+  Element getBottom() const noexcept { return lattice.getTop(); }
+  Element getTop() const noexcept { return lattice.getBottom(); }
+  LatticeComparison compare(const Element& a, const Element& b) const noexcept {
+    return reverseComparison(lattice.compare(a, b));
+  }
+  bool join(Element& self, Element other) const noexcept {
+    return lattice.meet(self, other);
+  }
+  bool meet(Element& self, Element other) const noexcept {
+    return lattice.join(self, other);
+  }
+};
+
+} // namespace wasm::analysis
+
+#endif // wasm_analysis_lattices_inverted_h