int32_t map(int32_t x, int32_t y, int32_t a, int32_t b, int32_t c) {
  int32_t z = 0;
#if (attr_function == 0) // linerar
  z = ___SMMLA(a << 3, x << 2, ___SMMLA(b << 3, y << 2, c));
#elif (attr_function == 1)  // quadratic
  z = ___SMMLA(___SMMUL(a << 3, x << 2) << 2, x << 3,
               ___SMMLA(___SMMUL(b << 3, y << 2) << 2, y << 3,
                        ___SMMUL(___SMMUL(c << 3, x << 2) << 2, y << 3)));
#elif (attr_function == 2)  // cubic1
  int32_t x3 = ___SMMUL(x << 2, ___SMMUL(x << 2, x << 3) << 3);
  int32_t y3 = ___SMMUL(y << 2, ___SMMUL(y << 2, y << 3) << 3);
  z = ___SMMLA(a << 3, x3 << 2, ___SMMLA(b << 3, y3 << 2, c));
#elif (attr_function == 3)  // cubic2
  int32_t x3 = ___SMMUL(x << 2, ___SMMUL(y << 2, y << 3) << 3);
  int32_t y3 = ___SMMUL(y << 2, ___SMMUL(x << 2, x << 3) << 3);
  z = ___SMMLA(a << 3, x3 << 2, ___SMMLA(b << 3, y3 << 2, c));
#elif (attr_function == 4)  // sine1
  SINE2TINTERP(___SMMUL(a << 3, x << 2) + ___SMMUL(b << 3, y << 2) + c << 5, z);
  z = z >> 4;
#elif (attr_function == 5)  // sine2
  SINE2TINTERP(___SMMUL(a << 3, ___SMMUL(x << 3, x << 2) << 2) +
                   ___SMMUL(b << 3, ___SMMUL(y << 3, y << 2) << 2) +
                   ___SMMUL(c << 3, ___SMMUL(x << 3, y << 2) << 2),
               z);
  z = z >> 4;
#elif (attr_function == 6)  // sine3
  int32_t x3 = ___SMMUL(x << 2, ___SMMUL(x << 2, x << 3) << 3);
  int32_t y3 = ___SMMUL(y << 2, ___SMMUL(y << 2, y << 3) << 3);
  SINE2TINTERP(___SMMLA(a << 3, x3 << 2, ___SMMLA(b << 3, y3 << 2, c)) << 5, z);
  z = z >> 4;
#elif (attr_function == 7)  // sine4
  int32_t x3 = ___SMMUL(x << 2, ___SMMUL(y << 2, y << 3) << 3);
  int32_t y3 = ___SMMUL(y << 2, ___SMMUL(x << 2, x << 3) << 3);
  SINE2TINTERP(___SMMLA(a << 3, x3 << 2, ___SMMLA(b << 3, y3 << 2, c)) << 5, z);
  z = z >> 4;
#elif (attr_function == 8)  // sine5
  SINE2TINTERP(___SMMLA(c << 3,
                        ___SMMUL(y << 2, ___SMMUL(x << 2, x << 3) << 3) << 2,
                        ___SMMLA(b << 3, ___SMMUL(y << 2, y << 3) << 2,
                                 ___SMMUL(a << 3, x << 2)))
                   << 5,
               z);
  z = z >> 4;
#elif (attr_function == 9)  // complex1
  float num = ___SMMUL(a << 2, ___SMMUL(x << 2, x << 3) << 3) +
              ___SMMUL(b << 2, ___SMMUL(y << 2, y << 3) << 3);
  float den = ___SMMLA(x << 2, y << 3, (c << 2));
  SINE2TINTERP((int32_t)(134217728.0f * num / den) << 5, z);
  z = z >> 4;
#elif (attr_function == 10) // feedback1
  SINE2TINTERP(___SMMUL(a << 3, x << 2) + ___SMMUL(b << 3, y << 2) +
                       ___SMMUL(c << 3, out_old << 2)
                   << 5,
               z);
  z = z >> 4;
  out_old = z;
#elif (attr_function == 11) // feedback2
  SINE2TINTERP(___SMMUL(a << 3, ___SMMUL(x << 3, x << 2) << 2) +
                       ___SMMUL(b << 3, ___SMMUL(y << 3, y << 2) << 2) +
                       ___SMMUL(c << 3, out_old << 2)
                   << 5,
               z);
  z = z >> 4;
  out_old = z;
#endif

  return z;
}

int32_t out_old = 0;

for (int i = 0; i < BUFSIZE; i++) {
  int32_t inX = __SSAT(inlet_x[i], 28);
  int32_t inY = __SSAT(inlet_y[i], 28);
  outlet_z[i] = map(param_sat ? inX : inlet_x[i], param_sat ? inY : inlet_y[i],
                    param_a, param_b, param_c);
}