T=d f ld
V=x
R=-1,1,0.25
F=(acos(x) >= 0) + \
  2*(0 <= acos(x)) + \
  4*(acos(x) <= 0) + \
  8*(0 >= acos(x))
C=fp_greaterOrEq(fp_acos(x), 0) + \
  2*fp_lessOrEq(0, fp_acos(x)) + \
  4*fp_lessOrEq(fp_acos(x), 0) + \
  8*fp_greaterOrEq(0, fp_acos(x))
