https://github.com/akkartik/mu/blob/master/subx/039debug.cc
 1 //: Some helpers for debugging.
 2 
 3 // Load the 'map' file generated during 'subx --map translate' when running 'subx --map --dump run'.
 4 // (It'll only affect the trace.)
 5 
 6 :(before "End Globals")
 7 map</*address*/uint32_t, string> Symbol_name;  // used only by 'subx run'
 8 :(before "End --map Settings")
 9 load_map("map");
10 :(code)
11 void load_map(const string& map_filename) {
12   ifstream fin(map_filename.c_str());
13   fin >> std::hex;
14   while (has_data(fin)) {
15     uint32_t addr = 0;
16     fin >> addr;
17     string name;
18     fin >> name;
19     put(Symbol_name, addr, name);
20   }
21 }
22 
23 :(after "Run One Instruction")
24 if (contains_key(Symbol_name, EIP))
25   trace(90, "run") << "== label " << get(Symbol_name, EIP) << end();