    ps_1_1
    def c4, 0, 0, 1, 1
    def c2, 0.5, 0.5, 0, 0
    def c1, 1, 1, 0, 0
    def c3, 0, 0, 1, 0
    tex t0
    tex t1
    tex t2
    tex t3
    sub_x4 r0.w, t0, t1
    mul t0.xyz, r0.w, c5
  + sub_x4 r1.w, t3, t2
    mad r0, r1.w, c6, t0
    add_x2 r0, r0, r0
    add r0, r0, c2
    add r0, r0, c3

// approximately 10 instruction slots used (4 texture, 6 arithmetic)
