Open-source lifetime inference/verification code.
PiperOrigin-RevId: 450954978
diff --git a/lifetime_analysis/lifetime_lattice.h b/lifetime_analysis/lifetime_lattice.h
new file mode 100644
index 0000000..68e8a0e
--- /dev/null
+++ b/lifetime_analysis/lifetime_lattice.h
@@ -0,0 +1,74 @@
+// Part of the Crubit project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef DEVTOOLS_RUST_CC_INTEROP_LIFETIME_ANALYSIS_LIFETIME_LATTICE_H_
+#define DEVTOOLS_RUST_CC_INTEROP_LIFETIME_ANALYSIS_LIFETIME_LATTICE_H_
+
+#include <string>
+#include <utility>
+#include <variant>
+
+#include "lifetime_analysis/points_to_map.h"
+#include "clang/Analysis/FlowSensitive/DataflowAnalysis.h"
+#include "clang/Analysis/FlowSensitive/DataflowLattice.h"
+#include "llvm/ADT/StringRef.h"
+
+namespace clang {
+namespace tidy {
+namespace lifetimes {
+
+class LifetimeLattice {
+ public:
+ // Creates a lattice holding an empty points-to map.
+ LifetimeLattice() = default;
+
+ LifetimeLattice(const LifetimeLattice&) = default;
+ LifetimeLattice(LifetimeLattice&&) = default;
+ LifetimeLattice& operator=(const LifetimeLattice&) = default;
+ LifetimeLattice& operator=(LifetimeLattice&&) = default;
+
+ // Creates a lattice containing the given points-to map.
+ explicit LifetimeLattice(PointsToMap points_to_map)
+ : var_(std::move(points_to_map)) {}
+
+ // Creates an error state containing the error message `err`.
+ explicit LifetimeLattice(std::string err) : var_(err) {}
+
+ // Returns the points-to map.
+ // Precondition: !IsError().
+ PointsToMap& PointsTo();
+ const PointsToMap& PointsTo() const;
+
+ // Returns whether the lattice is in the error state.
+ bool IsError() const { return std::holds_alternative<std::string>(var_); }
+
+ // Returns the error string.
+ // Precondition: IsError().
+ llvm::StringRef Error() const;
+
+ // Returns a human-readable representation of the lattice.
+ std::string ToString() const;
+
+ // Sets the lattice to the result of the "join" operation with `other` and
+ // returns the effect of the operation.
+ // If either of the lattices contains an error, sets this lattice to the
+ // first error encountered.
+ clang::dataflow::LatticeJoinEffect join(const LifetimeLattice& other);
+
+ // Compares for (in-)equality.
+ // All error states are considered to be equal.
+ bool operator==(const LifetimeLattice& other) const;
+ bool operator!=(const LifetimeLattice& other) const {
+ return !(*this == other);
+ }
+
+ private:
+ std::variant<PointsToMap, std::string> var_;
+};
+
+} // namespace lifetimes
+} // namespace tidy
+} // namespace clang
+
+#endif // DEVTOOLS_RUST_CC_INTEROP_LIFETIME_ANALYSIS_LIFETIME_LATTICE_H_
