TF_Output* dx, TF_Status* status, TF_Output* dy) {
  TF_AddGradientsWithPrefix(g, nullptr, y, ny, x, nx, dx, status, dy);
}

void TF_AddGradientsWithPrefix(TF_Graph* g, const char* prefix, TF_Output* y,
                               int ny, TF_Output* x, int nx, TF_Output* dx,
                               TF_Status* status, TF_Output* dy) {
#if defined(IS_MOBILE_PLATFORM) || defined(IS_SLIM_BUILD)

    // The expected graph looks like this if grad_inputs_provided.
    // If grad_inputs_provided is false, Const_0 will be a OnesLike op.
    //      ^             ^
    //    dy|           dx|        // MatMul Gradient Graph
    //      |             |
    //   MatMul_2      MatMul_1
    //   ^   ^          ^    ^
    //   |   |----------|    |
    //   |        ^          |

section. y, err := new(field.Element).SetBytes(x) if err != nil { return nil, errors.New("edwards25519: invalid point encoding length") } // -x² + y² = 1 + dx²y² // x² + dx²y² = x²(dy² + 1) = y² - 1 // x² = (y² - 1) / (dy² + 1) // u = y² - 1 y2 := new(field.Element).Square(y) u := new(field.Element).Subtract(y2, feOne) // v = dy² + 1 vv := new(field.Element).Multiply(y2, d) vv = vv.Add(vv, feOne) // x = +√(u/v) xx, wasSquare := new(field.Element).SqrtRatio(u, vv) if wasSquare == 0 { return nil, errors.New("edwards25519:...