Where in the swi-prolog code is the need for the creation of choice points checked

Discussion
1

I am looking to identify in the code where after a call of goal and before the execution of the goal, swi-prolog checks if choice points need to be generated.

It was suggested that it might be within i_enter in vmi.c, but i can’t see this relevaled in the code itself, so it seems that whether to create choice points has already been performed.

Edit:

Seems to be somewhere in pl_wam.c

VMI(I_ENTER, VIF_BREAK, 0, ())
{ ARGP = argFrameP(lTop, 0);

  if ( unlikely(LD->alerted) )
  {
#if O_DEBUGGER
    if ( debugstatus.debugging )
    { int action;

      SAVE_REGISTERS(qid);
      clearUninitialisedVarsFrame(FR, PC);
      action = tracePort(FR, BFR, UNIFY_PORT, PC PASS_LD);
      LOAD_REGISTERS(qid);

      switch( action )
      { case ACTION_RETRY:
	  goto retry;
	case ACTION_FAIL:
	  FRAME_FAILED;
	case ACTION_ABORT:
	  THROW_EXCEPTION;
      }
    }
#endif /*O_DEBUGGER*/

    CHECK_WAKEUP;
  }
  NEXT_INSTRUCTION;
}