isl_tab.c: push_union: handle NULL input

[isl.git] / test_inputs / codegen / omega / stride1-0.in

{ s0[In_1] -> [In_1] : exists (e0 = [(In_1)/3]: 3e0 = In_1 and In_1 >= 3 and In_1 <= 9) }
{  :  }
{ [i0] -> separate[o0] : o0 >= 0; [i0] -> atomic[o0] : o0 <= -1 }