[Types] Create function pointer type

[mari-mari]

Proposal

Add support to function pointers.

If a variable is called at some point, the type of it could be set to a function pointer.

Consider the following example:

$ python decompile.py extractme main

...
      int var_0;
...
      memcpy(var_0, 0x804c020, 71);
      var_0();
      var_0 = 0;
...

here, since the var_0 is being called after initialization, we can set its type to function pointer instead of integer.
extractme.zip

Approach

• add new type FunctionPointer with the following fields
  • name
  • return type
  • parameter / argument types
• update TypePropagation to consider variables that are being called.
• update CodeGenerator to generate declarations for the corresponding function pointers if needed.

[fnhartmann]

/cib

[github-actions]

Branch issue-45-_Types_Create_function_pointer_type created!