1 files changed, 94 insertions, 0 deletions
diff --git a/backend/include/rcc/CodeGen/MachineFunctionCloner.h b/backend/include/rcc/CodeGen/MachineFunctionCloner.h
new file mode 100644
index 0000000..09877d2
--- /dev/null
+++ b/backend/include/rcc/CodeGen/MachineFunctionCloner.h
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef RCC_CODEGEN_MACHINEFUNCTIONCLONER_H
+#define RCC_CODEGEN_MACHINEFUNCTIONCLONER_H
+
+#include "rcc/CodeGen/MachineIRTypes.h"
+#include "rcc/CodeGen/Register.h"
+#include "rcc/CodeGen/StableID.h"
+#include "rcc/Support/Error.h"
+
+#include <memory>
+#include <optional>
+#include <string>
+#include <unordered_map>
+
+namespace rcc {
+
+class MachineBasicBlock;
+class MachineFunction;
+class MachineInstr;
+class TargetDescription;
+
+struct MachineFunctionCloneOptions final {
+  MachineFunctionStableID NewStableID;
+  std::optional<std::string> NewName;
+};
+
+struct MachineFunctionCloneResult final {
+  MachineFunctionCloneResult();
+  MachineFunctionCloneResult(const MachineFunctionCloneResult &) = delete;
+  MachineFunctionCloneResult &operator=(const MachineFunctionCloneResult &) = delete;
+  MachineFunctionCloneResult(MachineFunctionCloneResult &&) noexcept;
+  MachineFunctionCloneResult &operator=(MachineFunctionCloneResult &&) noexcept;
+  ~MachineFunctionCloneResult();
+
+  std::unique_ptr<MachineFunction> ClonedFunction;
+  std::unordered_map<MachineBlockStableID, MachineBlockStableID> BlockStableIDs;
+  std::unordered_map<MachineInstrStableID, MachineInstrStableID> InstructionStableIDs;
+  std::unordered_map<Register, Register> VirtualRegisters;
+  std::unordered_map<FrameIndex, FrameIndex> FrameIndices;
+  std::unordered_map<ConstantPoolIndex, ConstantPoolIndex> ConstantPoolIndices;
+  std::unordered_map<JumpTableIndex, JumpTableIndex> JumpTableIndices;
+};
+
+class MachineFunctionCloneContext final {
+public:
+  [[nodiscard]] const MachineFunction &sourceFunction() const noexcept {
+    return Source;
+  }
+
+  [[nodiscard]] MachineFunction &destinationFunction() const noexcept {
+    return Destination;
+  }
+
+  [[nodiscard]] Expected<MachineBasicBlock *> mapBlock(const MachineBasicBlock &SourceBlock) const;
+  [[nodiscard]] Expected<MachineInstr *>
+  mapInstruction(const MachineInstr &SourceInstruction) const;
+  [[nodiscard]] Expected<MachineBlockStableID>
+  mapBlockStableID(MachineBlockStableID SourceID) const;
+  [[nodiscard]] Expected<MachineInstrStableID>
+  mapInstructionStableID(MachineInstrStableID SourceID) const;
+  [[nodiscard]] Expected<Register> mapRegister(Register SourceRegister) const;
+  [[nodiscard]] Expected<FrameIndex> mapFrameIndex(FrameIndex SourceIndex) const;
+  [[nodiscard]] Expected<ConstantPoolIndex>
+  mapConstantPoolIndex(ConstantPoolIndex SourceIndex) const;
+  [[nodiscard]] Expected<JumpTableIndex> mapJumpTableIndex(JumpTableIndex SourceIndex) const;
+
+private:
+  MachineFunctionCloneContext(
+      const MachineFunction &Source, MachineFunction &Destination,
+      const MachineFunctionCloneResult &Result,
+      const std::unordered_map<const MachineBasicBlock *, MachineBasicBlock *> &Blocks,
+      const std::unordered_map<const MachineInstr *, MachineInstr *> &Instructions) noexcept
+      : Source(Source), Destination(Destination), Result(Result), Blocks(Blocks),
+        Instructions(Instructions) {}
+
+  const MachineFunction &Source;
+  MachineFunction &Destination;
+  const MachineFunctionCloneResult &Result;
+  const std::unordered_map<const MachineBasicBlock *, MachineBasicBlock *> &Blocks;
+  const std::unordered_map<const MachineInstr *, MachineInstr *> &Instructions;
+
+  friend Expected<MachineFunctionCloneResult>
+  cloneMachineFunction(const MachineFunction &Source, const TargetDescription &Target,
+                       MachineFunctionCloneOptions Options);
+};
+
+[[nodiscard]] Expected<MachineFunctionCloneResult>
+cloneMachineFunction(const MachineFunction &Source, const TargetDescription &Target,
+                     MachineFunctionCloneOptions Options);
+
+} // namespace rcc
+
+#endif // RCC_CODEGEN_MACHINEFUNCTIONCLONER_H