Implementing ASM loop branching instruction

     I am implementing for my processor back end 2 loop instructions: set_loop_counter and Jump_if_counter_not_zero instruction (this is similar to PowerPC's CTR count register and MTCTR and BCTR instructions, which is implemented in the LLVM PowerPC back end, but I did not generate code for PPC with LLVM; see for details).
     For this I defined LLVM intrinsics: int_connex_repeat_x_times (for set_loop_counter) and int_connex_end_repeat (for Jump_if_counter_not_zero instruction).
     But then, in TableGen it seems I cannot give jump semantics for the Jump_if_counter_not_zero instruction, because it is already an ASM intrinsic. More exactly, I give:
         class END_REPEAT_DESC_BASE<InstrItinClass itin = NoItinerary> {
           dag OutOperandList = (outs);
           dag InOperandList = (ins);

           string AsmString = "END_REPEAT; // END_REPEAT";
           list<dag> Pattern = [(int_connex_end_repeat)];
           bit hasSideEffects = 1;
           InstrItinClass Itinerary = itin;

     I should give ISD::BRCOND semantics to my Jump_if_counter_not_zero (Connex) ASM instruction in order for the back end to perform eventual optimizations on the code such as loop invariant code motion, etc.
     Should I do this in the TableGen END_REPEAT_DESC_BASE spec by chaning the line:
         list<dag> Pattern = [(int_connex_end_repeat)];
         list<dag> Pattern = [(brcond targetAddress)];
     Or should I maybe do this in [Target]ISelLowering or [Target]ISelDAGToDAG by adding there BRCOND instead of the int_connex_end_repeat machine-independent node?

   Thank you,