{ float t = f_st[f_stp & 7]; f_st[f_stp & 7] = f_st[(f_stp + 6) & 7]; f_st[(f_stp + 6) & 7] = t; } // fxch
f_st[f_stp & 7] = -f_st[f_stp & 7];
f_st[(f_stp + 1) & 7] = atanf(f_st[(f_stp + 1) & 7] / f_st[f_stp & 7]); f_stp++;
{ float t = f_st[f_stp & 7]; f_st[f_stp & 7] = f_st[(f_stp + 6) & 7]; f_st[(f_stp + 6) & 7] = t; } // fxch
f_st[f_stp & 7] = -f_st[f_stp & 7];
f_st[(f_stp + 1) & 7] = atanf(f_st[(f_stp + 1) & 7] / f_st[f_stp & 7]); f_stp++;