mv.visitVarInsn(ALOAD, METHOD_ARGS_INDEX);
checkCast(mv, IRubyObject[].class);
mv.visitMethodInsn(INVOKEVIRTUAL, typePath, method, sig(ret, signature));
mv.visitInsn(ARETURN);
mv.visitMaxs(2, 3);
c = endCall(cw, mv, mname);
}
FastInvocationCallback ic = (FastInvocationCallback) c.newInstance();
ic.setArity(Arity.optional());
ic.setArgumentTypes(InvocationCallback.OPTIONAL_ARGS);