Sorry about the fwd in the description. This is my implementation:
fnDeclType = build_function_type_array(integer_type_node, argVect.NumOfItems, parmTypes); tree fnDecl = build_fn_decl(identifier->Str, fnDeclType); DECL_EXTERNAL(fnDecl) = 1; fnAddr = build1(ADDR_EXPR, build_pointer_type(fnDeclType), fnDecl); funcStmt = build_call_array_loc(identifier->Locus, integer_type_node, fnAddr, argVect.NumOfItems, parms); It works perfectly for calling functions. Not sure if it is the preferred way to do it, but gets the job done. > ...calling conventions (and anything defied in an Application Binary > Interface) is of course dependant on the architecture and operating > system you are compiling for, so you need to tell us that. I am not really that interested in calling convention. It only gets me to realise that methods (non static) and functions are not the same, even on a binary level. If I do it "correctly" on generic level GCC will be taking care of everything. But for what it's worth here is my specs: Intel x86_64, Ubuntu 16.04 LTS 64bit, gcc 5.2, compiled with g++ > type of the function being called is METHOD_TYPE and not FUNCTION_TYPE > (but that is actually good for consistency on any platform). Except > for static methods, those are functions in gcc internals. My implementation generates a FUNCTION_TYPE, is there an easy way to turn it into a METHOD_TYPE, like a single tree call. That will take care of consistency. Regards, André On Thu, Mar 30, 2017 at 4:03 PM, Martin Jambor <mjam...@suse.cz> wrote: > Hello, > > I am not sure if I can help you but... > > On Thu, Mar 30, 2017 at 08:05:07AM +0200, Andre Groenewald wrote: >> I am discovering the awesome world of GCC internals. I managed to >> develop a basic front end. It can call internal and external functions >> and link with standard libraries. All is good. >> >> The hunger for more does not end. I want to call c++ libraries and >> interact with c++ objects. >> >> My starting point was to call a test c++ method. I created a test c++ >> class with a test method/function. It was compiled into a library. The >> library was tested with c++ program and it worked. I manage to call it >> from my front end, but the parameter I passed was messed up. It was >> some random value every time I called the method. >> >> I disassembled my program and the test c++ program, then compared the >> two. I found that it uses a different register as in the case when >> calling a standard c style function. >> >> It seems that methods are different in the calling convention than >> normal functions, which is fine. All that I need to do is set correct >> tree property and every will work, right? The question is what tree >> property should I set, which macro should I use to set that property? >> > > ...calling conventions (and anything defied in an Application Binary > Interface) is of course dependant on the architecture and operating > system you are compiling for, so you need to tell us that. > > Having said that, the only target that I know about that uses > different argument passing for methods and for functions is > i686-mingw32 (MS Windows). If that is your case, make sure that the > type of the function being called is METHOD_TYPE and not FUNCTION_TYPE > (but that is actually good for consistency on any platform). Except > for static methods, those are functions in gcc internals. > > If this does not help, you'll need to provide much more details about > your whole setup. > > Martin >
