Exposed memory

Limitations

Exposing memory would be easy if PROS provided a better way to capture debug information and read it at runtime. On Linux systems debug info for executables is usually stored in the DWARF format and is used by debuggers to find the addresses of variables along with information on data types and functions.

Our Solution

Memory Types and the Type Database

v5dbg has a list of predefined, but extendable, memory types. Since memory types are just enums they do not directly convert into C++ types.

In order to convert a C++ type into a v5dbg_memory_type_e we use the type database which stores the hash_code of a std::type_info as the key and the memory type as the value.

$expose macro

The $expose macro takes in a variable and allows it to be exposed to the debugger. When $expose is invoked it generates code to register a void* to the variable with the debug server along with any type information which is obtained with the typeid operator.

When the $expose macro falls out of scope it automatically marks the variable as deallocated with the debug server. More information on how actual reading of variable memory can be found in the pretty printers section.