decomp: new feature in decompiler to hash the contents of a function for easy comparison

decompiler/ObjectFile/LinkedObjectFile.cpp

@@ -18,6 +18,7 @@
 
 #include "fmt/format.h"
 #include "third-party/json.hpp"
+#include "third-party/zstd/lib/common/xxhash.h"
 
 namespace decompiler {
 /*!
@@ -710,6 +711,20 @@ std::string LinkedObjectFile::print_asm_function_disassembly(const std::string&
   return result;
 }
 
+// Currently, just hashes the contents of every function, this makes it easy to
+// compare between games to see if something is identical
+void LinkedObjectFile::dump_asm_function_metadata(std::unordered_map<std::string, std::string> &map) {
+  ASSERT(segments <= 3);
+  for (int seg = segments; seg-- > 0;) {
+    // functions
+    for (auto& func : functions_by_seg.at(seg)) {
+      const auto& function_rep =  print_function_disassembly(func, seg, false, "");
+      const auto func_hash = XXH64(function_rep.data(), function_rep.size(), 0);
+      map.emplace(func.name(), fmt::format("{}", func_hash));
+    }
+  }
+}
+
 /*!
  * Print disassembled functions and data segments.
  */