Functionの挿入順を逆にするだけのPassを追加

src/Makefile

 TARGET := nykk.so
 SRCS   := \
 	nykk/pass/BlockWatermarkPass.cpp \
+	nykk/pass/FunctionWatermarkPass.cpp \
 	nykk/pass/InstructionWatermarkPass.cpp
 
 include ../cxx.mk

src/nykk/pass/FunctionWatermarkPass.cpp

+#include <llvm/IR/Function.h>
+#include <llvm/IR/Module.h>
+#include <llvm/Pass.h>
+#include <llvm/Support/raw_ostream.h>
+
+#include "../CircularBitStream.hpp"
+#include "../PermutationTable.hpp"
+#include "Opts.hpp"
+
+namespace
+{
+	/**
+	 * @brief      Watermarking pass by function ordering methods.
+	 */
+	class FunctionWatermarkPass
+		: public llvm::ModulePass
+	{
+	public:
+		static inline char ID; // Needed for LLVM.
+
+		/**
+		 * @brief      Constructor.
+		 */
+		explicit FunctionWatermarkPass()
+			: ModulePass(ID)
+		{
+		}
+
+		// Uncopyable, unmovable.
+		FunctionWatermarkPass(const FunctionWatermarkPass&) =delete;
+		FunctionWatermarkPass(FunctionWatermarkPass&&) =delete;
+
+		FunctionWatermarkPass& operator=(const FunctionWatermarkPass&) =delete;
+		FunctionWatermarkPass& operator=(FunctionWatermarkPass&&) =delete;
+
+		~FunctionWatermarkPass() =default;
+
+		/**
+		 * @brief      Processes modules.
+		 *
+		 * @param      module Reference to the module.
+		 *
+		 * @return     `true` if the module was changed.
+		 */
+		bool runOnModule(llvm::Module& module) override
+		{
+			const auto bit_stream = nykk::CircularBitStream::from_string(nykk::pass::watermark_opt);
+
+			std::size_t num_embedded_bits = 0;
+			bool is_changed = false;
+
+			auto functions = std::vector<std::reference_wrapper<llvm::Function>>(module.getFunctionList().rbegin(), module.getFunctionList().rend());
+
+			for (const auto& func : functions)
+			{
+				is_changed = true;
+				func.get().removeFromParent();
+				module.getFunctionList().push_back(&func.get());
+			}
+
+			llvm::errs() << module.getName() << ", " << module.size() << ", " << num_embedded_bits << "\n";
+
+			return is_changed;
+		}
+	};
+
+	// Registers pass.
+	const llvm::RegisterPass<FunctionWatermarkPass> pass_registry =
+	{
+		"func-wm",
+		"Watermarking pass by function ordering methods",
+	};
+}