Function ecall_softmax_grad

sgx_tf_ops/Enclave/Enclave.cpp:2258–2349

    }

void ecall_softmax_grad(float *input, float *grad, int N, int M, int C, float *output) {
    float *x = (float*)malloc(sizeof(float)*N);
    memset(x, 0, sizeof(float)*N);
    for(int j=0;j<N;j++){
        x[j] = 0.0f;
        float sum = input[insert*N+j];
        float c = 0.0f;
        for(int i=0;i<Nt;i++){
            float y = input[indexs[i]*N+j] - c;
            float t = sum + y;
            c = (t - sum) - y;
            sum = t;
        }
        x[j] = sum;
        }
    float *g = (float*)malloc(sizeof(float)*N);
    memset(g, 0, sizeof(float)*N);
    for(int j=0;j<N;j++){
        g[j] = 0.0f;
        float sum = grad[insert*N+j];
        float c = 0.0f;
        for(int i=0;i<Nt;i++){
            float y = grad[indexs[i]*N+j] - c;
            float t = sum + y;
            c = (t - sum) - y;
            sum = t;
        }
        g[j] = sum;
    }
    for (int i = 0; i < M; i++) {
        float max_val = x[i * C];
        for (int j = 1; j < C; j++) {
            max_val = fmaxf(max_val, x[i * C + j]);
        }
        float sum = 0.0f;
        for (int j = 0; j < C; j++) {
            float scaled_input = x[i * C + j] - max_val;
            sum += expf(scaled_input);
        }
        for (int j = 0; j < C; j++) {
            float scaled_input = x[i * C + j] - max_val;
            x[i * C + j] = expf(scaled_input) / sum;
        }
    }
    float *gt = (float *)malloc(sizeof(float) * M);
    memset(gt, 0, sizeof(float) * M);
    for (int i = 0; i < M; i++) {
        gt[i] = 0.0f;
        for (int j = 0; j < C; j++) {
            gt[i] += g[i * C + j] * x[i * C + j];
        }
    }
    for (int i = 0; i < M; i++) {
        for (int j = 0; j < C; j++) {
            g[i*C+j] = (g[i * C + j] - gt[i]) * x[i * C + j];
        }
    }
    float mean = 0.0f, std, mean_sqr = 0.0f;