diff --git a/src/layer/arm/gru_arm.cpp b/src/layer/arm/gru_arm.cpp
index 97a2bb61e..a49147813 100644
--- a/src/layer/arm/gru_arm.cpp
+++ b/src/layer/arm/gru_arm.cpp
@@ -695,13 +695,7 @@ int GRU_arm::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt) c
 
 int GRU_arm::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top_blobs, const Option& opt) const
 {
-    if (bottom_blobs.size() != 2 || top_blobs.size() != 2)
-    {
-        return forward(bottom_blobs[0], top_blobs[0], opt);
-    }
-
     const Mat& bottom_blob = bottom_blobs[0];
-
     int elembits = bottom_blob.elembits();
 
 #if __ARM_FEATURE_FP16_VECTOR_ARITHMETIC
@@ -720,24 +714,72 @@ int GRU_arm::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top
 #endif
 
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-    Mat& hidden_state = top_blobs[1];
+    int num_directions = direction == 2 ? 2 : 1;
 
-    //Copy previous states
-    hidden_state = bottom_blobs[1].clone(opt.blob_allocator);
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        hidden = bottom_blobs[1].clone(hidden_allocator);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 4u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 4u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
     {
-        int ret = gru(bottom_blob, top_blob, direction, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden_state, opt);
+        int ret = gru(bottom_blob, top_blob, direction, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden, opt);
         if (ret != 0)
             return ret;
     }
 
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = gru(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = gru(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const float* pf = top_blob_forward.row(i);
+            const float* pr = top_blob_reverse.row(i);
+            float* ptr = top_blob.row(i);
+
+            memcpy(ptr, pf, num_output * sizeof(float));
+            memcpy(ptr + num_output, pr, num_output * sizeof(float));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        top_blobs[1] = hidden;
+    }
+
     return 0;
 }
 
@@ -1625,16 +1667,29 @@ int GRU_arm::forward_fp16s(const std::vector<Mat>& bottom_blobs, std::vector<Mat
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
+    int num_directions = direction == 2 ? 2 : 1;
+
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_allocator;
+        cast_float16_to_float32(bottom_blobs[1], hidden, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
-    // copy previous states
-    Mat hidden;
-    cast_float16_to_float32(bottom_blobs[1], hidden, opt);
-
     // Uni directional
     if (direction == 0 || direction == 1)
     {
@@ -1643,7 +1698,42 @@ int GRU_arm::forward_fp16s(const std::vector<Mat>& bottom_blobs, std::vector<Mat
             return ret;
     }
 
-    cast_float32_to_float16(hidden, top_blobs[1], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = gru_fp16s(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = gru_fp16s(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const __fp16* pf = top_blob_forward.row<const __fp16>(i);
+            const __fp16* pr = top_blob_reverse.row<const __fp16>(i);
+            __fp16* ptr = top_blob.row<__fp16>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(__fp16));
+            memcpy(ptr + num_output, pr, num_output * sizeof(__fp16));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        cast_float32_to_float16(hidden, top_blobs[1], opt);
+    }
 
     return 0;
 }
@@ -1711,16 +1801,29 @@ int GRU_arm::forward_fp16sa(const std::vector<Mat>& bottom_blobs, std::vector<Ma
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
+    int num_directions = direction == 2 ? 2 : 1;
+
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_allocator;
+        cast_float16_to_float32(bottom_blobs[1], hidden, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
-    // copy previous states
-    Mat hidden;
-    cast_float16_to_float32(bottom_blobs[1], hidden, opt);
-
     // Uni directional
     if (direction == 0 || direction == 1)
     {
@@ -1729,7 +1832,42 @@ int GRU_arm::forward_fp16sa(const std::vector<Mat>& bottom_blobs, std::vector<Ma
             return ret;
     }
 
-    cast_float32_to_float16(hidden, top_blobs[1], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = gru_fp16sa(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = gru_fp16sa(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const __fp16* pf = top_blob_forward.row<const __fp16>(i);
+            const __fp16* pr = top_blob_reverse.row<const __fp16>(i);
+            __fp16* ptr = top_blob.row<__fp16>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(__fp16));
+            memcpy(ptr + num_output, pr, num_output * sizeof(__fp16));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        top_blobs[1] = hidden;
+    }
 
     return 0;
 }
@@ -2365,16 +2503,29 @@ int GRU_arm::forward_bf16s(const std::vector<Mat>& bottom_blobs, std::vector<Mat
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
+    int num_directions = direction == 2 ? 2 : 1;
 
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_allocator;
+        cast_bfloat16_to_float32(bottom_blobs[1], hidden, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
+
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
-    // copy previous states
-    Mat hidden;
-    cast_bfloat16_to_float32(bottom_blobs[1], hidden, opt);
-
     // Uni directional
     if (direction == 0 || direction == 1)
     {
@@ -2383,7 +2534,42 @@ int GRU_arm::forward_bf16s(const std::vector<Mat>& bottom_blobs, std::vector<Mat
             return ret;
     }
 
-    cast_float32_to_bfloat16(hidden, top_blobs[1], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = gru_bf16s(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = gru_bf16s(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const unsigned short* pf = top_blob_forward.row<const unsigned short>(i);
+            const unsigned short* pr = top_blob_reverse.row<const unsigned short>(i);
+            unsigned short* ptr = top_blob.row<unsigned short>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(unsigned short));
+            memcpy(ptr + num_output, pr, num_output * sizeof(unsigned short));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        cast_float32_to_bfloat16(hidden, top_blobs[1], opt);
+    }
 
     return 0;
 }
diff --git a/src/layer/arm/lstm_arm.cpp b/src/layer/arm/lstm_arm.cpp
index 7b8511b8f..185b8ff54 100644
--- a/src/layer/arm/lstm_arm.cpp
+++ b/src/layer/arm/lstm_arm.cpp
@@ -423,13 +423,7 @@ int LSTM_arm::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt)
 
 int LSTM_arm::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top_blobs, const Option& opt) const
 {
-    if (bottom_blobs.size() != 3 || top_blobs.size() != 3)
-    {
-        return forward(bottom_blobs[0], top_blobs[0], opt);
-    }
-
     const Mat& bottom_blob = bottom_blobs[0];
-
     int elembits = bottom_blob.elembits();
 
 #if __ARM_FEATURE_FP16_VECTOR_ARITHMETIC
@@ -448,26 +442,82 @@ int LSTM_arm::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& to
 #endif
 
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-    Mat& hidden_state = top_blobs[1];
-    Mat& cell_state = top_blobs[2];
+    int num_directions = direction == 2 ? 2 : 1;
+
+    Mat hidden;
+    Mat cell;
+    Allocator* hidden_cell_allocator = top_blobs.size() == 3 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 3)
+    {
+        hidden = bottom_blobs[1].clone(hidden_cell_allocator);
+        cell = bottom_blobs[2].clone(hidden_cell_allocator);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
 
-    //Copy previous states
-    hidden_state = bottom_blobs[1].clone(opt.blob_allocator);
-    cell_state = bottom_blobs[2].clone(opt.blob_allocator);
+        cell.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (cell.empty())
+            return -100;
+        cell.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 4u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 4u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
     {
-        int ret = lstm(bottom_blob, top_blob, direction, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden_state, cell_state, opt);
+        int ret = lstm(bottom_blob, top_blob, direction, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden, cell, opt);
         if (ret != 0)
             return ret;
     }
 
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        Mat cell0 = cell.row_range(0, 1);
+        int ret0 = lstm(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, cell0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        Mat cell1 = cell.row_range(1, 1);
+        int ret1 = lstm(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, cell1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const float* pf = top_blob_forward.row(i);
+            const float* pr = top_blob_reverse.row(i);
+            float* ptr = top_blob.row(i);
+
+            memcpy(ptr, pf, num_output * sizeof(float));
+            memcpy(ptr + num_output, pr, num_output * sizeof(float));
+        }
+    }
+
+    if (top_blobs.size() == 3)
+    {
+        top_blobs[1] = hidden;
+        top_blobs[2] = cell;
+    }
+
     return 0;
 }
 
@@ -1182,17 +1232,35 @@ int LSTM_arm::forward_fp16s(const std::vector<Mat>& bottom_blobs, std::vector<Ma
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
-    if (top_blob.empty())
-        return -100;
+    int num_directions = direction == 2 ? 2 : 1;
 
-    // copy previous states
     Mat hidden;
     Mat cell;
-    cast_float16_to_float32(bottom_blobs[1], hidden, opt);
-    cast_float16_to_float32(bottom_blobs[2], cell, opt);
+    Allocator* hidden_cell_allocator = top_blobs.size() == 3 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 3)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_cell_allocator;
+        cast_float16_to_float32(bottom_blobs[1], hidden, opt_cast);
+        cast_float16_to_float32(bottom_blobs[2], cell, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+
+        cell.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (cell.empty())
+            return -100;
+        cell.fill(0.f);
+    }
+
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
+    if (top_blob.empty())
+        return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
@@ -1202,8 +1270,45 @@ int LSTM_arm::forward_fp16s(const std::vector<Mat>& bottom_blobs, std::vector<Ma
             return ret;
     }
 
-    cast_float32_to_float16(hidden, top_blobs[1], opt);
-    cast_float32_to_float16(cell, top_blobs[2], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        Mat cell0 = cell.row_range(0, 1);
+        int ret0 = lstm_fp16s(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, cell0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        Mat cell1 = cell.row_range(1, 1);
+        int ret1 = lstm_fp16s(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, cell1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const __fp16* pf = top_blob_forward.row<const __fp16>(i);
+            const __fp16* pr = top_blob_reverse.row<const __fp16>(i);
+            __fp16* ptr = top_blob.row<__fp16>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(__fp16));
+            memcpy(ptr + num_output, pr, num_output * sizeof(__fp16));
+        }
+    }
+
+    if (top_blobs.size() == 3)
+    {
+        cast_float32_to_float16(hidden, top_blobs[1], opt);
+        cast_float32_to_float16(cell, top_blobs[2], opt);
+    }
 
     return 0;
 }
@@ -1277,17 +1382,35 @@ int LSTM_arm::forward_fp16sa(const std::vector<Mat>& bottom_blobs, std::vector<M
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
-    if (top_blob.empty())
-        return -100;
+    int num_directions = direction == 2 ? 2 : 1;
 
-    // copy previous states
     Mat hidden;
     Mat cell;
-    cast_float16_to_float32(bottom_blobs[1], hidden, opt);
-    cast_float16_to_float32(bottom_blobs[2], cell, opt);
+    Allocator* hidden_cell_allocator = top_blobs.size() == 3 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 3)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_cell_allocator;
+        cast_float16_to_float32(bottom_blobs[1], hidden, opt_cast);
+        cast_float16_to_float32(bottom_blobs[2], cell, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+
+        cell.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (cell.empty())
+            return -100;
+        cell.fill(0.f);
+    }
+
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
+    if (top_blob.empty())
+        return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
@@ -1297,8 +1420,45 @@ int LSTM_arm::forward_fp16sa(const std::vector<Mat>& bottom_blobs, std::vector<M
             return ret;
     }
 
-    cast_float32_to_float16(hidden, top_blobs[1], opt);
-    cast_float32_to_float16(cell, top_blobs[2], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        Mat cell0 = cell.row_range(0, 1);
+        int ret0 = lstm_fp16sa(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, cell0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        Mat cell1 = cell.row_range(1, 1);
+        int ret1 = lstm_fp16sa(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, cell1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const __fp16* pf = top_blob_forward.row<const __fp16>(i);
+            const __fp16* pr = top_blob_reverse.row<const __fp16>(i);
+            __fp16* ptr = top_blob.row<__fp16>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(__fp16));
+            memcpy(ptr + num_output, pr, num_output * sizeof(__fp16));
+        }
+    }
+
+    if (top_blobs.size() == 3)
+    {
+        cast_float32_to_float16(hidden, top_blobs[1], opt);
+        cast_float32_to_float16(cell, top_blobs[2], opt);
+    }
 
     return 0;
 }
@@ -1664,17 +1824,35 @@ int LSTM_arm::forward_bf16s(const std::vector<Mat>& bottom_blobs, std::vector<Ma
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
-    if (top_blob.empty())
-        return -100;
+    int num_directions = direction == 2 ? 2 : 1;
 
-    // copy previous states
     Mat hidden;
     Mat cell;
-    cast_bfloat16_to_float32(bottom_blobs[1], hidden, opt);
-    cast_bfloat16_to_float32(bottom_blobs[2], cell, opt);
+    Allocator* hidden_cell_allocator = top_blobs.size() == 3 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 3)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_cell_allocator;
+        cast_bfloat16_to_float32(bottom_blobs[1], hidden, opt_cast);
+        cast_bfloat16_to_float32(bottom_blobs[2], cell, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+
+        cell.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (cell.empty())
+            return -100;
+        cell.fill(0.f);
+    }
+
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
+    if (top_blob.empty())
+        return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
@@ -1684,8 +1862,45 @@ int LSTM_arm::forward_bf16s(const std::vector<Mat>& bottom_blobs, std::vector<Ma
             return ret;
     }
 
-    cast_float32_to_bfloat16(hidden, top_blobs[1], opt);
-    cast_float32_to_bfloat16(cell, top_blobs[2], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        Mat cell0 = cell.row_range(0, 1);
+        int ret0 = lstm_bf16s(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, cell0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        Mat cell1 = cell.row_range(1, 1);
+        int ret1 = lstm_bf16s(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, cell1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const unsigned short* pf = top_blob_forward.row<const unsigned short>(i);
+            const unsigned short* pr = top_blob_reverse.row<const unsigned short>(i);
+            unsigned short* ptr = top_blob.row<unsigned short>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(unsigned short));
+            memcpy(ptr + num_output, pr, num_output * sizeof(unsigned short));
+        }
+    }
+
+    if (top_blobs.size() == 3)
+    {
+        cast_float32_to_bfloat16(hidden, top_blobs[1], opt);
+        cast_float32_to_bfloat16(cell, top_blobs[2], opt);
+    }
 
     return 0;
 }
diff --git a/src/layer/arm/rnn_arm.cpp b/src/layer/arm/rnn_arm.cpp
index 9bd5bcc29..c113eb282 100644
--- a/src/layer/arm/rnn_arm.cpp
+++ b/src/layer/arm/rnn_arm.cpp
@@ -377,13 +377,7 @@ int RNN_arm::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt) c
 
 int RNN_arm::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top_blobs, const Option& opt) const
 {
-    if (bottom_blobs.size() != 2 || top_blobs.size() != 2)
-    {
-        return forward(bottom_blobs[0], top_blobs[0], opt);
-    }
-
     const Mat& bottom_blob = bottom_blobs[0];
-
     int elembits = bottom_blob.elembits();
 
 #if __ARM_FEATURE_FP16_VECTOR_ARITHMETIC
@@ -402,24 +396,72 @@ int RNN_arm::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top
 #endif
 
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-    Mat& hidden_state = top_blobs[1];
+    int num_directions = direction == 2 ? 2 : 1;
 
-    //Copy previous states
-    hidden_state = bottom_blobs[1].clone(opt.blob_allocator);
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        hidden = bottom_blobs[1].clone(hidden_allocator);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 4u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 4u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
     {
-        int ret = rnn(bottom_blob, top_blob, direction, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden_state, opt);
+        int ret = rnn(bottom_blob, top_blob, direction, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden, opt);
         if (ret != 0)
             return ret;
     }
 
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = rnn(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = rnn(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const float* pf = top_blob_forward.row(i);
+            const float* pr = top_blob_reverse.row(i);
+            float* ptr = top_blob.row(i);
+
+            memcpy(ptr, pf, num_output * sizeof(float));
+            memcpy(ptr + num_output, pr, num_output * sizeof(float));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        top_blobs[1] = hidden;
+    }
+
     return 0;
 }
 
@@ -965,16 +1007,29 @@ int RNN_arm::forward_fp16s(const std::vector<Mat>& bottom_blobs, std::vector<Mat
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
+    int num_directions = direction == 2 ? 2 : 1;
 
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_allocator;
+        cast_float16_to_float32(bottom_blobs[1], hidden, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
+
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
-    // copy previous states
-    Mat hidden;
-    cast_float16_to_float32(bottom_blobs[1], hidden, opt);
-
     // Uni directional
     if (direction == 0 || direction == 1)
     {
@@ -983,7 +1038,42 @@ int RNN_arm::forward_fp16s(const std::vector<Mat>& bottom_blobs, std::vector<Mat
             return ret;
     }
 
-    cast_float32_to_float16(hidden, top_blobs[1], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = rnn_fp16s(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = rnn_fp16s(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const __fp16* pf = top_blob_forward.row<const __fp16>(i);
+            const __fp16* pr = top_blob_reverse.row<const __fp16>(i);
+            __fp16* ptr = top_blob.row<__fp16>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(__fp16));
+            memcpy(ptr + num_output, pr, num_output * sizeof(__fp16));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        cast_float32_to_float16(hidden, top_blobs[1], opt);
+    }
 
     return 0;
 }
@@ -1051,16 +1141,29 @@ int RNN_arm::forward_fp16sa(const std::vector<Mat>& bottom_blobs, std::vector<Ma
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
+    int num_directions = direction == 2 ? 2 : 1;
+
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_allocator;
+        cast_float16_to_float32(bottom_blobs[1], hidden, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
-    // copy previous states
-    Mat hidden;
-    cast_float16_to_float32(bottom_blobs[1], hidden, opt);
-
     // Uni directional
     if (direction == 0 || direction == 1)
     {
@@ -1069,7 +1172,42 @@ int RNN_arm::forward_fp16sa(const std::vector<Mat>& bottom_blobs, std::vector<Ma
             return ret;
     }
 
-    cast_float32_to_float16(hidden, top_blobs[1], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = rnn_fp16sa(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = rnn_fp16sa(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const __fp16* pf = top_blob_forward.row<const __fp16>(i);
+            const __fp16* pr = top_blob_reverse.row<const __fp16>(i);
+            __fp16* ptr = top_blob.row<__fp16>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(__fp16));
+            memcpy(ptr + num_output, pr, num_output * sizeof(__fp16));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        cast_float32_to_float16(hidden, top_blobs[1], opt);
+    }
 
     return 0;
 }
@@ -1387,16 +1525,29 @@ int RNN_arm::forward_bf16s(const std::vector<Mat>& bottom_blobs, std::vector<Mat
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
+    int num_directions = direction == 2 ? 2 : 1;
+
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_allocator;
+        cast_bfloat16_to_float32(bottom_blobs[1], hidden, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
-    // copy previous states
-    Mat hidden;
-    cast_bfloat16_to_float32(bottom_blobs[1], hidden, opt);
-
     // Uni directional
     if (direction == 0 || direction == 1)
     {
@@ -1405,7 +1556,42 @@ int RNN_arm::forward_bf16s(const std::vector<Mat>& bottom_blobs, std::vector<Mat
             return ret;
     }
 
-    cast_float32_to_bfloat16(hidden, top_blobs[1], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = rnn_bf16s(bottom_blob, top_blob_forward, 0, weight_xc_data_packed.channel(0), bias_c_data_packed.channel(0), weight_hc_data_packed.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = rnn_bf16s(bottom_blob, top_blob_reverse, 1, weight_xc_data_packed.channel(1), bias_c_data_packed.channel(1), weight_hc_data_packed.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const unsigned short* pf = top_blob_forward.row<const unsigned short>(i);
+            const unsigned short* pr = top_blob_reverse.row<const unsigned short>(i);
+            unsigned short* ptr = top_blob.row<unsigned short>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(unsigned short));
+            memcpy(ptr + num_output, pr, num_output * sizeof(unsigned short));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        cast_float32_to_bfloat16(hidden, top_blobs[1], opt);
+    }
 
     return 0;
 }
diff --git a/src/layer/gru.cpp b/src/layer/gru.cpp
index 6183f4f0a..5690252ad 100644
--- a/src/layer/gru.cpp
+++ b/src/layer/gru.cpp
@@ -29,8 +29,6 @@ int GRU::load_param(const ParamDict& pd)
     num_output = pd.get(0, 0);
     weight_data_size = pd.get(1, 0);
     direction = pd.get(2, 0);
-    if (direction == 2)
-        one_blob_only = true;
     return 0;
 }
 
@@ -223,30 +221,74 @@ int GRU::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt) const
 
 int GRU::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top_blobs, const Option& opt) const
 {
-    if (bottom_blobs.size() != 2 || top_blobs.size() != 2)
-    {
-        return forward(bottom_blobs[0], top_blobs[0], opt);
-    }
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-    Mat& hidden_state = top_blobs[1];
+    int num_directions = direction == 2 ? 2 : 1;
 
-    //Copy previous states
-    hidden_state = bottom_blobs[1].clone(opt.blob_allocator);
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        hidden = bottom_blobs[1].clone(hidden_allocator);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 4u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 4u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
     {
-        int ret = gru(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden_state, opt);
+        int ret = gru(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden, opt);
         if (ret != 0)
             return ret;
     }
 
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = gru(bottom_blob, top_blob_forward, 0, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = gru(bottom_blob, top_blob_reverse, 1, weight_xc_data.channel(1), bias_c_data.channel(1), weight_hc_data.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const float* pf = top_blob_forward.row(i);
+            const float* pr = top_blob_reverse.row(i);
+            float* ptr = top_blob.row(i);
+
+            memcpy(ptr, pf, num_output * sizeof(float));
+            memcpy(ptr + num_output, pr, num_output * sizeof(float));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        top_blobs[1] = hidden;
+    }
+
     return 0;
 }
 
diff --git a/src/layer/lstm.cpp b/src/layer/lstm.cpp
index ad7720085..7907e1dc0 100644
--- a/src/layer/lstm.cpp
+++ b/src/layer/lstm.cpp
@@ -29,8 +29,6 @@ int LSTM::load_param(const ParamDict& pd)
     num_output = pd.get(0, 0);
     weight_data_size = pd.get(1, 0);
     direction = pd.get(2, 0);
-    if (direction == 2)
-        one_blob_only = true;
     return 0;
 }
 
@@ -232,32 +230,84 @@ int LSTM::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt) cons
 
 int LSTM::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top_blobs, const Option& opt) const
 {
-    if (bottom_blobs.size() != 3 || top_blobs.size() != 3)
-    {
-        return forward(bottom_blobs[0], top_blobs[0], opt);
-    }
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-    Mat& hidden_state = top_blobs[1];
-    Mat& cell_state = top_blobs[2];
+    int num_directions = direction == 2 ? 2 : 1;
+
+    Mat hidden;
+    Mat cell;
+    Allocator* hidden_cell_allocator = top_blobs.size() == 3 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 3)
+    {
+        hidden = bottom_blobs[1].clone(hidden_cell_allocator);
+        cell = bottom_blobs[2].clone(hidden_cell_allocator);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
 
-    //Copy previous states
-    hidden_state = bottom_blobs[1].clone(opt.blob_allocator);
-    cell_state = bottom_blobs[2].clone(opt.blob_allocator);
+        cell.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (cell.empty())
+            return -100;
+        cell.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 4u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 4u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
     {
-        int ret = lstm(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden_state, cell_state, opt);
+        int ret = lstm(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden, cell, opt);
         if (ret != 0)
             return ret;
     }
 
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        Mat cell0 = cell.row_range(0, 1);
+        int ret0 = lstm(bottom_blob, top_blob_forward, 0, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden0, cell0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        Mat cell1 = cell.row_range(1, 1);
+        int ret1 = lstm(bottom_blob, top_blob_reverse, 1, weight_xc_data.channel(1), bias_c_data.channel(1), weight_hc_data.channel(1), hidden1, cell1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const float* pf = top_blob_forward.row(i);
+            const float* pr = top_blob_reverse.row(i);
+            float* ptr = top_blob.row(i);
+
+            memcpy(ptr, pf, num_output * sizeof(float));
+            memcpy(ptr + num_output, pr, num_output * sizeof(float));
+        }
+    }
+
+    if (top_blobs.size() == 3)
+    {
+        top_blobs[1] = hidden;
+        top_blobs[2] = cell;
+    }
+
     return 0;
 }
 
diff --git a/src/layer/riscv/gru_riscv.cpp b/src/layer/riscv/gru_riscv.cpp
index 0ebb2879b..20666f5ee 100644
--- a/src/layer/riscv/gru_riscv.cpp
+++ b/src/layer/riscv/gru_riscv.cpp
@@ -301,11 +301,6 @@ int GRU_riscv::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt)
 
 int GRU_riscv::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top_blobs, const Option& opt) const
 {
-    if (bottom_blobs.size() != 2 || top_blobs.size() != 2)
-    {
-        return forward(bottom_blobs[0], top_blobs[0], opt);
-    }
-
     const Mat& bottom_blob = bottom_blobs[0];
     int elembits = bottom_blob.elembits();
 
@@ -321,24 +316,73 @@ int GRU_riscv::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& t
 #endif
 
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-    Mat& hidden_state = top_blobs[1];
+    int num_directions = direction == 2 ? 2 : 1;
 
-    //Copy previous states
-    hidden_state = bottom_blobs[1].clone(opt.blob_allocator);
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        hidden = bottom_blobs[1].clone(hidden_allocator);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 4u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 4u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
     {
-        int ret = gru(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden_state, opt);
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret = gru(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden0, opt);
         if (ret != 0)
             return ret;
     }
 
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = gru(bottom_blob, top_blob_forward, 0, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = gru(bottom_blob, top_blob_reverse, 1, weight_xc_data.channel(1), bias_c_data.channel(1), weight_hc_data.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const float* pf = top_blob_forward.row(i);
+            const float* pr = top_blob_reverse.row(i);
+            float* ptr = top_blob.row(i);
+
+            memcpy(ptr, pf, num_output * sizeof(float));
+            memcpy(ptr + num_output, pr, num_output * sizeof(float));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        top_blobs[1] = hidden;
+    }
+
     return 0;
 #endif
     return GRU::forward(bottom_blobs, top_blobs, opt);
@@ -587,24 +631,75 @@ int GRU_riscv::forward_fp16s(const std::vector<Mat>& bottom_blobs, std::vector<M
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
+    int num_directions = direction == 2 ? 2 : 1;
+
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_allocator;
+        cast_float16_to_float32(bottom_blobs[1], hidden, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
+
     Mat& top_blob = top_blobs[0];
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
-    //Copy previous states
-    Mat hidden;
-    cast_float16_to_float32(bottom_blobs[1], hidden, opt);
-
     // Uni directional
     if (direction == 0 || direction == 1)
     {
-        int ret = gru_fp16s(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden, opt);
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret = gru_fp16s(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden0, opt);
         if (ret != 0)
             return ret;
     }
 
-    cast_float32_to_float16(hidden, top_blobs[1], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = gru_fp16s(bottom_blob, top_blob_forward, 0, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = gru_fp16s(bottom_blob, top_blob_reverse, 1, weight_xc_data.channel(1), bias_c_data.channel(1), weight_hc_data.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const __fp16* pf = top_blob_forward.row<const __fp16>(i);
+            const __fp16* pr = top_blob_reverse.row<const __fp16>(i);
+            __fp16* ptr = top_blob.row<__fp16>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(__fp16));
+            memcpy(ptr + num_output, pr, num_output * sizeof(__fp16));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        cast_float32_to_float16(hidden, top_blobs[1], opt);
+    }
+
     return 0;
 }
 
@@ -853,15 +948,29 @@ int GRU_riscv::forward_fp16sa(const std::vector<Mat>& bottom_blobs, std::vector<
 {
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
+    int num_directions = direction == 2 ? 2 : 1;
+
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        Option opt_cast = opt;
+        opt_cast.blob_allocator = hidden_allocator;
+        cast_float16_to_float32(bottom_blobs[1], hidden, opt_cast);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
+
     Mat& top_blob = top_blobs[0];
-    top_blob.create(num_output, T, 2u, opt.blob_allocator);
+    top_blob.create(num_output * num_directions, T, 2u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
-    //Copy previous states
-    Mat hidden;
-    cast_float16_to_float32(bottom_blobs[1], hidden, opt);
-
     // Uni directional
     if (direction == 0 || direction == 1)
     {
@@ -870,11 +979,46 @@ int GRU_riscv::forward_fp16sa(const std::vector<Mat>& bottom_blobs, std::vector<
             return ret;
     }
 
-    cast_float32_to_float16(hidden, top_blobs[1], opt);
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 2u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = gru_fp16sa(bottom_blob, top_blob_forward, 0, weight_xc_data_fp16sa.channel(0), bias_c_data_fp16sa.channel(0), weight_hc_data_fp16sa.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = gru_fp16sa(bottom_blob, top_blob_reverse, 1, weight_xc_data_fp16sa.channel(1), bias_c_data_fp16sa.channel(1), weight_hc_data_fp16sa.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const __fp16* pf = top_blob_forward.row<const __fp16>(i);
+            const __fp16* pr = top_blob_reverse.row<const __fp16>(i);
+            __fp16* ptr = top_blob.row<__fp16>(i);
+
+            memcpy(ptr, pf, num_output * sizeof(__fp16));
+            memcpy(ptr + num_output, pr, num_output * sizeof(__fp16));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        cast_float32_to_float16(hidden, top_blobs[1], opt);
+    }
 
     return 0;
 }
 
 #endif
 
-} // namespace ncnn
\ No newline at end of file
+} // namespace ncnn
diff --git a/src/layer/rnn.cpp b/src/layer/rnn.cpp
index efe9b8461..54627d5c7 100644
--- a/src/layer/rnn.cpp
+++ b/src/layer/rnn.cpp
@@ -29,8 +29,6 @@ int RNN::load_param(const ParamDict& pd)
     num_output = pd.get(0, 0);
     weight_data_size = pd.get(1, 0);
     direction = pd.get(2, 0);
-    if (direction == 2)
-        one_blob_only = true;
     return 0;
 }
 
@@ -172,30 +170,74 @@ int RNN::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt) const
 
 int RNN::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top_blobs, const Option& opt) const
 {
-    if (bottom_blobs.size() != 2 || top_blobs.size() != 2)
-    {
-        return forward(bottom_blobs[0], top_blobs[0], opt);
-    }
     const Mat& bottom_blob = bottom_blobs[0];
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-    Mat& hidden_state = top_blobs[1];
+    int num_directions = direction == 2 ? 2 : 1;
 
-    //Copy previous states
-    hidden_state = bottom_blobs[1].clone(opt.blob_allocator);
+    Mat hidden;
+    Allocator* hidden_allocator = top_blobs.size() == 2 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 2)
+    {
+        hidden = bottom_blobs[1].clone(hidden_allocator);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
+    }
 
-    top_blob.create(num_output, T, 4u, opt.blob_allocator);
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 4u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
 
     // Uni directional
     if (direction == 0 || direction == 1)
     {
-        int ret = rnn(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden_state, opt);
+        int ret = rnn(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden, opt);
         if (ret != 0)
             return ret;
     }
 
+    if (direction == 2)
+    {
+        Mat top_blob_forward(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        int ret0 = rnn(bottom_blob, top_blob_forward, 0, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden0, opt);
+        if (ret0 != 0)
+            return ret0;
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        int ret1 = rnn(bottom_blob, top_blob_reverse, 1, weight_xc_data.channel(1), bias_c_data.channel(1), weight_hc_data.channel(1), hidden1, opt);
+        if (ret1 != 0)
+            return ret1;
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const float* pf = top_blob_forward.row(i);
+            const float* pr = top_blob_reverse.row(i);
+            float* ptr = top_blob.row(i);
+
+            memcpy(ptr, pf, num_output * sizeof(float));
+            memcpy(ptr + num_output, pr, num_output * sizeof(float));
+        }
+    }
+
+    if (top_blobs.size() == 2)
+    {
+        top_blobs[1] = hidden;
+    }
+
     return 0;
 }
 
diff --git a/src/layer/x86/lstm_x86.cpp b/src/layer/x86/lstm_x86.cpp
index 0c8d42d13..6e55fd700 100644
--- a/src/layer/x86/lstm_x86.cpp
+++ b/src/layer/x86/lstm_x86.cpp
@@ -910,42 +910,123 @@ int LSTM_x86::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt)
 int LSTM_x86::forward(const std::vector<Mat>& bottom_blobs, std::vector<Mat>& top_blobs, const Option& opt) const
 {
 #if __AVX__
-    if (bottom_blobs.size() != 3 || top_blobs.size() != 3)
-    {
-        return forward(bottom_blobs[0], top_blobs[0], opt);
-    }
     const Mat& bottom_blob = bottom_blobs[0];
-
     int T = bottom_blob.h;
-    Mat& top_blob = top_blobs[0];
-    Mat& hidden_state = top_blobs[1];
-    Mat& cell_state = top_blobs[2];
+    int num_directions = direction == 2 ? 2 : 1;
 
-    //Copy previous states
-    hidden_state = bottom_blobs[1].clone(opt.blob_allocator);
-    cell_state = bottom_blobs[2].clone(opt.blob_allocator);
+    Mat hidden;
+    Mat cell;
+    Allocator* hidden_cell_allocator = top_blobs.size() == 3 ? opt.blob_allocator : opt.workspace_allocator;
+    if (bottom_blobs.size() == 3)
+    {
+        hidden = bottom_blobs[1].clone(hidden_cell_allocator);
+        cell = bottom_blobs[2].clone(hidden_cell_allocator);
+    }
+    else
+    {
+        hidden.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (hidden.empty())
+            return -100;
+        hidden.fill(0.f);
 
-    top_blob.create(num_output, T, 4u, opt.blob_allocator);
+        cell.create(num_output, num_directions, 4u, hidden_cell_allocator);
+        if (cell.empty())
+            return -100;
+        cell.fill(0.f);
+    }
+
+    Mat& top_blob = top_blobs[0];
+    top_blob.create(num_output * num_directions, T, 4u, opt.blob_allocator);
     if (top_blob.empty())
         return -100;
-#if __AVX2__
-    if (opt.use_weight_fp16_storage)
+
+    // Uni directional
+    if (direction == 0 || direction == 1)
     {
-        // Uni directional
-        int ret = lstm_fp16(bottom_blob, top_blob, direction, weight_xc_data_fp16.channel(0), bias_c_data.channel(0), weight_hc_data_fp16.channel(0), hidden_state, cell_state, opt);
-        if (ret != 0)
-            return ret;
+#if __AVX2__
+        if (opt.use_weight_fp16_storage)
+        {
+            int ret = lstm_fp16(bottom_blob, top_blob, direction, weight_xc_data_fp16.channel(0), bias_c_data.channel(0), weight_hc_data_fp16.channel(0), hidden, cell, opt);
+            if (ret != 0)
+                return ret;
+        }
+        else
+        {
+#endif
+            int ret = lstm(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden, cell, opt);
+            if (ret != 0)
+                return ret;
+#if __AVX2__
+        }
+#endif
     }
-    else
+
+    if (direction == 2)
     {
+        Mat top_blob_forward(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_forward.empty())
+            return -100;
+
+        Mat top_blob_reverse(num_output, T, 4u, opt.workspace_allocator);
+        if (top_blob_reverse.empty())
+            return -100;
+
+        Mat hidden0 = hidden.row_range(0, 1);
+        Mat cell0 = cell.row_range(0, 1);
+#if __AVX2__
+        if (opt.use_weight_fp16_storage)
+        {
+            int ret = lstm_fp16(bottom_blob, top_blob_forward, 0, weight_xc_data_fp16.channel(0), bias_c_data.channel(0), weight_hc_data_fp16.channel(0), hidden0, cell0, opt);
+            if (ret != 0)
+                return ret;
+        }
+        else
+        {
 #endif
-        // Uni directional
-        int ret = lstm(bottom_blob, top_blob, direction, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden_state, cell_state, opt);
-        if (ret != 0)
-            return ret;
+            int ret0 = lstm(bottom_blob, top_blob_forward, 0, weight_xc_data.channel(0), bias_c_data.channel(0), weight_hc_data.channel(0), hidden0, cell0, opt);
+            if (ret0 != 0)
+                return ret0;
 #if __AVX2__
-    }
+        }
 #endif
+
+        Mat hidden1 = hidden.row_range(1, 1);
+        Mat cell1 = cell.row_range(1, 1);
+#if __AVX2__
+        if (opt.use_weight_fp16_storage)
+        {
+            int ret = lstm_fp16(bottom_blob, top_blob_reverse, 1, weight_xc_data_fp16.channel(1), bias_c_data.channel(1), weight_hc_data_fp16.channel(1), hidden1, cell1, opt);
+            if (ret != 0)
+                return ret;
+        }
+        else
+        {
+#endif
+            int ret1 = lstm(bottom_blob, top_blob_reverse, 1, weight_xc_data.channel(1), bias_c_data.channel(1), weight_hc_data.channel(1), hidden1, cell1, opt);
+            if (ret1 != 0)
+                return ret1;
+#if __AVX2__
+        }
+#endif
+
+        // concat w
+        for (int i = 0; i < T; i++)
+        {
+            const float* pf = top_blob_forward.row(i);
+            const float* pr = top_blob_reverse.row(i);
+            float* ptr = top_blob.row(i);
+
+            memcpy(ptr, pf, num_output * sizeof(float));
+            memcpy(ptr + num_output, pr, num_output * sizeof(float));
+        }
+    }
+
+    if (top_blobs.size() == 3)
+    {
+        top_blobs[1] = hidden;
+        top_blobs[2] = cell;
+    }
+
     return 0;
 #else
     return LSTM::forward(bottom_blobs, top_blobs, opt);
diff --git a/tests/test_gru.cpp b/tests/test_gru.cpp
index af3b178bb..006e54487 100644
--- a/tests/test_gru.cpp
+++ b/tests/test_gru.cpp
@@ -42,19 +42,20 @@ static int test_gru(const ncnn::Mat& a, int outch, int direction)
 int test_gru_layer_with_hidden(const ncnn::Mat& a, int outch, int direction)
 {
     int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
 
     ncnn::ParamDict pd;
     pd.set(0, outch);
-    pd.set(1, outch * input_size * 3);
+    pd.set(1, outch * input_size * 3 * num_directions);
     pd.set(2, direction);
 
     std::vector<ncnn::Mat> weights(3);
-    weights[0] = RandomMat(outch * input_size * 3);
-    weights[1] = RandomMat(outch * 4);
-    weights[2] = RandomMat(outch * outch * 3);
+    weights[0] = RandomMat(outch * input_size * 3 * num_directions);
+    weights[1] = RandomMat(outch * 4 * num_directions);
+    weights[2] = RandomMat(outch * outch * 3 * num_directions);
 
     // initial hidden state
-    ncnn::Mat hidden = RandomMat(outch);
+    ncnn::Mat hidden = RandomMat(outch, num_directions);
 
     std::vector<ncnn::Mat> as(2);
     as[0] = a;
@@ -69,6 +70,64 @@ int test_gru_layer_with_hidden(const ncnn::Mat& a, int outch, int direction)
     return ret;
 }
 
+int test_gru_layer_with_hidden_input(const ncnn::Mat& a, int outch, int direction)
+{
+    int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
+
+    ncnn::ParamDict pd;
+    pd.set(0, outch);
+    pd.set(1, outch * input_size * 3 * num_directions);
+    pd.set(2, direction);
+
+    std::vector<ncnn::Mat> weights(3);
+    weights[0] = RandomMat(outch * input_size * 3 * num_directions);
+    weights[1] = RandomMat(outch * 4 * num_directions);
+    weights[2] = RandomMat(outch * outch * 3 * num_directions);
+
+    // initial hidden state
+    ncnn::Mat hidden = RandomMat(outch, num_directions);
+
+    std::vector<ncnn::Mat> as(2);
+    as[0] = a;
+    as[1] = hidden;
+
+    int ret = test_layer<ncnn::GRU>("GRU", pd, weights, as, 1);
+    if (ret != 0)
+    {
+        fprintf(stderr, "test_gru_layer_with_hidden_input failed a.dims=%d a=(%d %d %d) outch=%d, direction = %d \n", a.dims, a.w, a.h, a.c, outch, direction);
+    }
+
+    return ret;
+}
+
+int test_gru_layer_with_hidden_output(const ncnn::Mat& a, int outch, int direction)
+{
+    int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
+
+    ncnn::ParamDict pd;
+    pd.set(0, outch);
+    pd.set(1, outch * input_size * 3 * num_directions);
+    pd.set(2, direction);
+
+    std::vector<ncnn::Mat> weights(3);
+    weights[0] = RandomMat(outch * input_size * 3 * num_directions);
+    weights[1] = RandomMat(outch * 4 * num_directions);
+    weights[2] = RandomMat(outch * outch * 3 * num_directions);
+
+    std::vector<ncnn::Mat> as(1);
+    as[0] = a;
+
+    int ret = test_layer<ncnn::GRU>("GRU", pd, weights, as, 2);
+    if (ret != 0)
+    {
+        fprintf(stderr, "test_gru_layer_with_hidden_output failed a.dims=%d a=(%d %d %d) outch=%d, direction = %d \n", a.dims, a.w, a.h, a.c, outch, direction);
+    }
+
+    return ret;
+}
+
 static int test_gru_0()
 {
     return 0
@@ -86,6 +145,14 @@ static int test_gru_0()
 static int test_gru_1()
 {
     return 0
+           || test_gru_layer_with_hidden(RandomMat(4, 4), 1, 2)
+           || test_gru_layer_with_hidden(RandomMat(8, 2), 2, 2)
+           || test_gru_layer_with_hidden(RandomMat(16, 8), 7, 2)
+           || test_gru_layer_with_hidden(RandomMat(17, 8), 8, 2)
+           || test_gru_layer_with_hidden(RandomMat(19, 15), 8, 2)
+           || test_gru_layer_with_hidden(RandomMat(5, 16), 16, 2)
+           || test_gru_layer_with_hidden(RandomMat(3, 16), 8, 2)
+           || test_gru_layer_with_hidden(RandomMat(2, 5), 99, 2)
            || test_gru_layer_with_hidden(RandomMat(4, 4), 1, 1)
            || test_gru_layer_with_hidden(RandomMat(8, 2), 2, 1)
            || test_gru_layer_with_hidden(RandomMat(16, 8), 7, 1)
@@ -101,7 +168,57 @@ static int test_gru_1()
            || test_gru_layer_with_hidden(RandomMat(19, 15), 8, 0)
            || test_gru_layer_with_hidden(RandomMat(5, 16), 16, 0)
            || test_gru_layer_with_hidden(RandomMat(3, 16), 8, 0)
-           || test_gru_layer_with_hidden(RandomMat(2, 5), 17, 0);
+           || test_gru_layer_with_hidden(RandomMat(2, 5), 17, 0)
+
+           || test_gru_layer_with_hidden_input(RandomMat(4, 4), 1, 2)
+           || test_gru_layer_with_hidden_input(RandomMat(8, 2), 2, 2)
+           || test_gru_layer_with_hidden_input(RandomMat(16, 8), 7, 2)
+           || test_gru_layer_with_hidden_input(RandomMat(17, 8), 8, 2)
+           || test_gru_layer_with_hidden_input(RandomMat(19, 15), 8, 2)
+           || test_gru_layer_with_hidden_input(RandomMat(5, 16), 16, 2)
+           || test_gru_layer_with_hidden_input(RandomMat(3, 16), 8, 2)
+           || test_gru_layer_with_hidden_input(RandomMat(2, 5), 99, 2)
+           || test_gru_layer_with_hidden_input(RandomMat(4, 4), 1, 1)
+           || test_gru_layer_with_hidden_input(RandomMat(8, 2), 2, 1)
+           || test_gru_layer_with_hidden_input(RandomMat(16, 8), 7, 1)
+           || test_gru_layer_with_hidden_input(RandomMat(17, 8), 8, 1)
+           || test_gru_layer_with_hidden_input(RandomMat(19, 15), 8, 1)
+           || test_gru_layer_with_hidden_input(RandomMat(5, 16), 16, 1)
+           || test_gru_layer_with_hidden_input(RandomMat(3, 16), 8, 1)
+           || test_gru_layer_with_hidden_input(RandomMat(2, 5), 99, 1)
+           || test_gru_layer_with_hidden_input(RandomMat(4, 2), 1, 0)
+           || test_gru_layer_with_hidden_input(RandomMat(8, 2), 2, 0)
+           || test_gru_layer_with_hidden_input(RandomMat(16, 8), 7, 0)
+           || test_gru_layer_with_hidden_input(RandomMat(17, 8), 8, 0)
+           || test_gru_layer_with_hidden_input(RandomMat(19, 15), 8, 0)
+           || test_gru_layer_with_hidden_input(RandomMat(5, 16), 16, 0)
+           || test_gru_layer_with_hidden_input(RandomMat(3, 16), 8, 0)
+           || test_gru_layer_with_hidden_input(RandomMat(2, 5), 17, 0)
+
+           || test_gru_layer_with_hidden_output(RandomMat(4, 4), 1, 2)
+           || test_gru_layer_with_hidden_output(RandomMat(8, 2), 2, 2)
+           || test_gru_layer_with_hidden_output(RandomMat(16, 8), 7, 2)
+           || test_gru_layer_with_hidden_output(RandomMat(17, 8), 8, 2)
+           || test_gru_layer_with_hidden_output(RandomMat(19, 15), 8, 2)
+           || test_gru_layer_with_hidden_output(RandomMat(5, 16), 16, 2)
+           || test_gru_layer_with_hidden_output(RandomMat(3, 16), 8, 2)
+           || test_gru_layer_with_hidden_output(RandomMat(2, 5), 99, 2)
+           || test_gru_layer_with_hidden_output(RandomMat(4, 4), 1, 1)
+           || test_gru_layer_with_hidden_output(RandomMat(8, 2), 2, 1)
+           || test_gru_layer_with_hidden_output(RandomMat(16, 8), 7, 1)
+           || test_gru_layer_with_hidden_output(RandomMat(17, 8), 8, 1)
+           || test_gru_layer_with_hidden_output(RandomMat(19, 15), 8, 1)
+           || test_gru_layer_with_hidden_output(RandomMat(5, 16), 16, 1)
+           || test_gru_layer_with_hidden_output(RandomMat(3, 16), 8, 1)
+           || test_gru_layer_with_hidden_output(RandomMat(2, 5), 99, 1)
+           || test_gru_layer_with_hidden_output(RandomMat(4, 2), 1, 0)
+           || test_gru_layer_with_hidden_output(RandomMat(8, 2), 2, 0)
+           || test_gru_layer_with_hidden_output(RandomMat(16, 8), 7, 0)
+           || test_gru_layer_with_hidden_output(RandomMat(17, 8), 8, 0)
+           || test_gru_layer_with_hidden_output(RandomMat(19, 15), 8, 0)
+           || test_gru_layer_with_hidden_output(RandomMat(5, 16), 16, 0)
+           || test_gru_layer_with_hidden_output(RandomMat(3, 16), 8, 0)
+           || test_gru_layer_with_hidden_output(RandomMat(2, 5), 17, 0);
 }
 
 static int test_gru_2()
diff --git a/tests/test_lstm.cpp b/tests/test_lstm.cpp
index 9b337d685..f002a1aec 100644
--- a/tests/test_lstm.cpp
+++ b/tests/test_lstm.cpp
@@ -42,22 +42,23 @@ static int test_lstm(const ncnn::Mat& a, int outch, int direction)
 int test_lstm_layer_with_hidden(const ncnn::Mat& a, int outch, int direction)
 {
     int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
 
     ncnn::ParamDict pd;
     pd.set(0, outch);
-    pd.set(1, outch * input_size * 4);
+    pd.set(1, outch * input_size * 4 * num_directions);
     pd.set(2, direction);
 
     std::vector<ncnn::Mat> weights(3);
-    weights[0] = RandomMat(outch * input_size * 4);
-    weights[1] = RandomMat(outch * 4);
-    weights[2] = RandomMat(outch * outch * 4);
+    weights[0] = RandomMat(outch * input_size * 4 * num_directions);
+    weights[1] = RandomMat(outch * 4 * num_directions);
+    weights[2] = RandomMat(outch * outch * 4 * num_directions);
 
     // initial hidden state
-    ncnn::Mat hidden = RandomMat(outch);
+    ncnn::Mat hidden = RandomMat(outch, num_directions);
 
     // initial cell state
-    ncnn::Mat cell = RandomMat(outch);
+    ncnn::Mat cell = RandomMat(outch, num_directions);
 
     std::vector<ncnn::Mat> as(3);
     as[0] = a;
@@ -73,6 +74,68 @@ int test_lstm_layer_with_hidden(const ncnn::Mat& a, int outch, int direction)
     return ret;
 }
 
+int test_lstm_layer_with_hidden_input(const ncnn::Mat& a, int outch, int direction)
+{
+    int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
+
+    ncnn::ParamDict pd;
+    pd.set(0, outch);
+    pd.set(1, outch * input_size * 4 * num_directions);
+    pd.set(2, direction);
+
+    std::vector<ncnn::Mat> weights(3);
+    weights[0] = RandomMat(outch * input_size * 4 * num_directions);
+    weights[1] = RandomMat(outch * 4 * num_directions);
+    weights[2] = RandomMat(outch * outch * 4 * num_directions);
+
+    // initial hidden state
+    ncnn::Mat hidden = RandomMat(outch, num_directions);
+
+    // initial cell state
+    ncnn::Mat cell = RandomMat(outch, num_directions);
+
+    std::vector<ncnn::Mat> as(3);
+    as[0] = a;
+    as[1] = hidden;
+    as[2] = cell;
+
+    int ret = test_layer<ncnn::LSTM>("LSTM", pd, weights, as, 1);
+    if (ret != 0)
+    {
+        fprintf(stderr, "test_lstm_layer_with_hidden_input failed a.dims=%d a=(%d %d %d) outch=%d, direction = %d \n", a.dims, a.w, a.h, a.c, outch, direction);
+    }
+
+    return ret;
+}
+
+int test_lstm_layer_with_hidden_output(const ncnn::Mat& a, int outch, int direction)
+{
+    int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
+
+    ncnn::ParamDict pd;
+    pd.set(0, outch);
+    pd.set(1, outch * input_size * 4 * num_directions);
+    pd.set(2, direction);
+
+    std::vector<ncnn::Mat> weights(3);
+    weights[0] = RandomMat(outch * input_size * 4 * num_directions);
+    weights[1] = RandomMat(outch * 4 * num_directions);
+    weights[2] = RandomMat(outch * outch * 4 * num_directions);
+
+    std::vector<ncnn::Mat> as(1);
+    as[0] = a;
+
+    int ret = test_layer<ncnn::LSTM>("LSTM", pd, weights, as, 3);
+    if (ret != 0)
+    {
+        fprintf(stderr, "test_lstm_layer_with_hidden_output failed a.dims=%d a=(%d %d %d) outch=%d, direction = %d \n", a.dims, a.w, a.h, a.c, outch, direction);
+    }
+
+    return ret;
+}
+
 static int test_lstm_0()
 {
     return 0
@@ -90,6 +153,14 @@ static int test_lstm_0()
 static int test_lstm_1()
 {
     return 0
+           || test_lstm_layer_with_hidden(RandomMat(4, 4), 1, 2)
+           || test_lstm_layer_with_hidden(RandomMat(8, 2), 2, 2)
+           || test_lstm_layer_with_hidden(RandomMat(16, 8), 7, 2)
+           || test_lstm_layer_with_hidden(RandomMat(17, 8), 8, 2)
+           || test_lstm_layer_with_hidden(RandomMat(19, 15), 8, 2)
+           || test_lstm_layer_with_hidden(RandomMat(5, 16), 16, 2)
+           || test_lstm_layer_with_hidden(RandomMat(3, 16), 8, 2)
+           || test_lstm_layer_with_hidden(RandomMat(2, 5), 99, 2)
            || test_lstm_layer_with_hidden(RandomMat(4, 4), 1, 1)
            || test_lstm_layer_with_hidden(RandomMat(8, 2), 2, 1)
            || test_lstm_layer_with_hidden(RandomMat(16, 8), 7, 1)
@@ -105,7 +176,57 @@ static int test_lstm_1()
            || test_lstm_layer_with_hidden(RandomMat(19, 15), 8, 0)
            || test_lstm_layer_with_hidden(RandomMat(5, 16), 16, 0)
            || test_lstm_layer_with_hidden(RandomMat(3, 16), 8, 0)
-           || test_lstm_layer_with_hidden(RandomMat(2, 5), 17, 0);
+           || test_lstm_layer_with_hidden(RandomMat(2, 5), 17, 0)
+
+           || test_lstm_layer_with_hidden_input(RandomMat(4, 4), 1, 2)
+           || test_lstm_layer_with_hidden_input(RandomMat(8, 2), 2, 2)
+           || test_lstm_layer_with_hidden_input(RandomMat(16, 8), 7, 2)
+           || test_lstm_layer_with_hidden_input(RandomMat(17, 8), 8, 2)
+           || test_lstm_layer_with_hidden_input(RandomMat(19, 15), 8, 2)
+           || test_lstm_layer_with_hidden_input(RandomMat(5, 16), 16, 2)
+           || test_lstm_layer_with_hidden_input(RandomMat(3, 16), 8, 2)
+           || test_lstm_layer_with_hidden_input(RandomMat(2, 5), 99, 2)
+           || test_lstm_layer_with_hidden_input(RandomMat(4, 4), 1, 1)
+           || test_lstm_layer_with_hidden_input(RandomMat(8, 2), 2, 1)
+           || test_lstm_layer_with_hidden_input(RandomMat(16, 8), 7, 1)
+           || test_lstm_layer_with_hidden_input(RandomMat(17, 8), 8, 1)
+           || test_lstm_layer_with_hidden_input(RandomMat(19, 15), 8, 1)
+           || test_lstm_layer_with_hidden_input(RandomMat(5, 16), 16, 1)
+           || test_lstm_layer_with_hidden_input(RandomMat(3, 16), 8, 1)
+           || test_lstm_layer_with_hidden_input(RandomMat(2, 5), 99, 1)
+           || test_lstm_layer_with_hidden_input(RandomMat(4, 2), 1, 0)
+           || test_lstm_layer_with_hidden_input(RandomMat(8, 2), 2, 0)
+           || test_lstm_layer_with_hidden_input(RandomMat(16, 8), 7, 0)
+           || test_lstm_layer_with_hidden_input(RandomMat(17, 8), 8, 0)
+           || test_lstm_layer_with_hidden_input(RandomMat(19, 15), 8, 0)
+           || test_lstm_layer_with_hidden_input(RandomMat(5, 16), 16, 0)
+           || test_lstm_layer_with_hidden_input(RandomMat(3, 16), 8, 0)
+           || test_lstm_layer_with_hidden_input(RandomMat(2, 5), 17, 0)
+
+           || test_lstm_layer_with_hidden_output(RandomMat(4, 4), 1, 2)
+           || test_lstm_layer_with_hidden_output(RandomMat(8, 2), 2, 2)
+           || test_lstm_layer_with_hidden_output(RandomMat(16, 8), 7, 2)
+           || test_lstm_layer_with_hidden_output(RandomMat(17, 8), 8, 2)
+           || test_lstm_layer_with_hidden_output(RandomMat(19, 15), 8, 2)
+           || test_lstm_layer_with_hidden_output(RandomMat(5, 16), 16, 2)
+           || test_lstm_layer_with_hidden_output(RandomMat(3, 16), 8, 2)
+           || test_lstm_layer_with_hidden_output(RandomMat(2, 5), 99, 2)
+           || test_lstm_layer_with_hidden_output(RandomMat(4, 4), 1, 1)
+           || test_lstm_layer_with_hidden_output(RandomMat(8, 2), 2, 1)
+           || test_lstm_layer_with_hidden_output(RandomMat(16, 8), 7, 1)
+           || test_lstm_layer_with_hidden_output(RandomMat(17, 8), 8, 1)
+           || test_lstm_layer_with_hidden_output(RandomMat(19, 15), 8, 1)
+           || test_lstm_layer_with_hidden_output(RandomMat(5, 16), 16, 1)
+           || test_lstm_layer_with_hidden_output(RandomMat(3, 16), 8, 1)
+           || test_lstm_layer_with_hidden_output(RandomMat(2, 5), 99, 1)
+           || test_lstm_layer_with_hidden_output(RandomMat(4, 2), 1, 0)
+           || test_lstm_layer_with_hidden_output(RandomMat(8, 2), 2, 0)
+           || test_lstm_layer_with_hidden_output(RandomMat(16, 8), 7, 0)
+           || test_lstm_layer_with_hidden_output(RandomMat(17, 8), 8, 0)
+           || test_lstm_layer_with_hidden_output(RandomMat(19, 15), 8, 0)
+           || test_lstm_layer_with_hidden_output(RandomMat(5, 16), 16, 0)
+           || test_lstm_layer_with_hidden_output(RandomMat(3, 16), 8, 0)
+           || test_lstm_layer_with_hidden_output(RandomMat(2, 5), 17, 0);
 }
 
 static int test_lstm_2()
diff --git a/tests/test_rnn.cpp b/tests/test_rnn.cpp
index 0be24f9e6..31b89a22a 100644
--- a/tests/test_rnn.cpp
+++ b/tests/test_rnn.cpp
@@ -42,19 +42,20 @@ static int test_rnn(const ncnn::Mat& a, int outch, int direction)
 int test_rnn_layer_with_hidden(const ncnn::Mat& a, int outch, int direction)
 {
     int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
 
     ncnn::ParamDict pd;
     pd.set(0, outch);
-    pd.set(1, outch * input_size);
+    pd.set(1, outch * input_size * num_directions);
     pd.set(2, direction);
 
     std::vector<ncnn::Mat> weights(3);
-    weights[0] = RandomMat(outch * input_size);
-    weights[1] = RandomMat(outch);
-    weights[2] = RandomMat(outch * outch);
+    weights[0] = RandomMat(outch * input_size * num_directions);
+    weights[1] = RandomMat(outch * num_directions);
+    weights[2] = RandomMat(outch * outch * num_directions);
 
     // initial hidden state
-    ncnn::Mat hidden = RandomMat(outch);
+    ncnn::Mat hidden = RandomMat(outch, num_directions);
 
     std::vector<ncnn::Mat> as(2);
     as[0] = a;
@@ -69,6 +70,64 @@ int test_rnn_layer_with_hidden(const ncnn::Mat& a, int outch, int direction)
     return ret;
 }
 
+int test_rnn_layer_with_hidden_input(const ncnn::Mat& a, int outch, int direction)
+{
+    int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
+
+    ncnn::ParamDict pd;
+    pd.set(0, outch);
+    pd.set(1, outch * input_size * num_directions);
+    pd.set(2, direction);
+
+    std::vector<ncnn::Mat> weights(3);
+    weights[0] = RandomMat(outch * input_size * num_directions);
+    weights[1] = RandomMat(outch * num_directions);
+    weights[2] = RandomMat(outch * outch * num_directions);
+
+    // initial hidden state
+    ncnn::Mat hidden = RandomMat(outch, num_directions);
+
+    std::vector<ncnn::Mat> as(2);
+    as[0] = a;
+    as[1] = hidden;
+
+    int ret = test_layer<ncnn::RNN>("RNN", pd, weights, as, 1);
+    if (ret != 0)
+    {
+        fprintf(stderr, "test_rnn_layer_with_hidden_input failed a.dims=%d a=(%d %d %d) outch=%d, direction = %d \n", a.dims, a.w, a.h, a.c, outch, direction);
+    }
+
+    return ret;
+}
+
+int test_rnn_layer_with_hidden_output(const ncnn::Mat& a, int outch, int direction)
+{
+    int input_size = a.w;
+    int num_directions = direction == 2 ? 2 : 1;
+
+    ncnn::ParamDict pd;
+    pd.set(0, outch);
+    pd.set(1, outch * input_size * num_directions);
+    pd.set(2, direction);
+
+    std::vector<ncnn::Mat> weights(3);
+    weights[0] = RandomMat(outch * input_size * num_directions);
+    weights[1] = RandomMat(outch * num_directions);
+    weights[2] = RandomMat(outch * outch * num_directions);
+
+    std::vector<ncnn::Mat> as(1);
+    as[0] = a;
+
+    int ret = test_layer<ncnn::RNN>("RNN", pd, weights, as, 2);
+    if (ret != 0)
+    {
+        fprintf(stderr, "test_rnn_layer_with_hidden_output failed a.dims=%d a=(%d %d %d) outch=%d, direction = %d \n", a.dims, a.w, a.h, a.c, outch, direction);
+    }
+
+    return ret;
+}
+
 static int test_rnn_0()
 {
     return 0
@@ -86,6 +145,14 @@ static int test_rnn_0()
 static int test_rnn_1()
 {
     return 0
+           || test_rnn_layer_with_hidden(RandomMat(4, 4), 1, 2)
+           || test_rnn_layer_with_hidden(RandomMat(8, 2), 2, 2)
+           || test_rnn_layer_with_hidden(RandomMat(16, 8), 7, 2)
+           || test_rnn_layer_with_hidden(RandomMat(17, 8), 8, 2)
+           || test_rnn_layer_with_hidden(RandomMat(19, 15), 8, 2)
+           || test_rnn_layer_with_hidden(RandomMat(5, 16), 16, 2)
+           || test_rnn_layer_with_hidden(RandomMat(3, 16), 8, 2)
+           || test_rnn_layer_with_hidden(RandomMat(2, 5), 99, 2)
            || test_rnn_layer_with_hidden(RandomMat(4, 4), 1, 1)
            || test_rnn_layer_with_hidden(RandomMat(8, 2), 2, 1)
            || test_rnn_layer_with_hidden(RandomMat(16, 8), 7, 1)
@@ -101,7 +168,57 @@ static int test_rnn_1()
            || test_rnn_layer_with_hidden(RandomMat(19, 15), 8, 0)
            || test_rnn_layer_with_hidden(RandomMat(5, 16), 16, 0)
            || test_rnn_layer_with_hidden(RandomMat(3, 16), 8, 0)
-           || test_rnn_layer_with_hidden(RandomMat(2, 5), 17, 0);
+           || test_rnn_layer_with_hidden(RandomMat(2, 5), 17, 0)
+
+           || test_rnn_layer_with_hidden_input(RandomMat(4, 4), 1, 2)
+           || test_rnn_layer_with_hidden_input(RandomMat(8, 2), 2, 2)
+           || test_rnn_layer_with_hidden_input(RandomMat(16, 8), 7, 2)
+           || test_rnn_layer_with_hidden_input(RandomMat(17, 8), 8, 2)
+           || test_rnn_layer_with_hidden_input(RandomMat(19, 15), 8, 2)
+           || test_rnn_layer_with_hidden_input(RandomMat(5, 16), 16, 2)
+           || test_rnn_layer_with_hidden_input(RandomMat(3, 16), 8, 2)
+           || test_rnn_layer_with_hidden_input(RandomMat(2, 5), 99, 2)
+           || test_rnn_layer_with_hidden_input(RandomMat(4, 4), 1, 1)
+           || test_rnn_layer_with_hidden_input(RandomMat(8, 2), 2, 1)
+           || test_rnn_layer_with_hidden_input(RandomMat(16, 8), 7, 1)
+           || test_rnn_layer_with_hidden_input(RandomMat(17, 8), 8, 1)
+           || test_rnn_layer_with_hidden_input(RandomMat(19, 15), 8, 1)
+           || test_rnn_layer_with_hidden_input(RandomMat(5, 16), 16, 1)
+           || test_rnn_layer_with_hidden_input(RandomMat(3, 16), 8, 1)
+           || test_rnn_layer_with_hidden_input(RandomMat(2, 5), 99, 1)
+           || test_rnn_layer_with_hidden_input(RandomMat(4, 2), 1, 0)
+           || test_rnn_layer_with_hidden_input(RandomMat(8, 2), 2, 0)
+           || test_rnn_layer_with_hidden_input(RandomMat(16, 8), 7, 0)
+           || test_rnn_layer_with_hidden_input(RandomMat(17, 8), 8, 0)
+           || test_rnn_layer_with_hidden_input(RandomMat(19, 15), 8, 0)
+           || test_rnn_layer_with_hidden_input(RandomMat(5, 16), 16, 0)
+           || test_rnn_layer_with_hidden_input(RandomMat(3, 16), 8, 0)
+           || test_rnn_layer_with_hidden_input(RandomMat(2, 5), 17, 0)
+
+           || test_rnn_layer_with_hidden_output(RandomMat(4, 4), 1, 2)
+           || test_rnn_layer_with_hidden_output(RandomMat(8, 2), 2, 2)
+           || test_rnn_layer_with_hidden_output(RandomMat(16, 8), 7, 2)
+           || test_rnn_layer_with_hidden_output(RandomMat(17, 8), 8, 2)
+           || test_rnn_layer_with_hidden_output(RandomMat(19, 15), 8, 2)
+           || test_rnn_layer_with_hidden_output(RandomMat(5, 16), 16, 2)
+           || test_rnn_layer_with_hidden_output(RandomMat(3, 16), 8, 2)
+           || test_rnn_layer_with_hidden_output(RandomMat(2, 5), 99, 2)
+           || test_rnn_layer_with_hidden_output(RandomMat(4, 4), 1, 1)
+           || test_rnn_layer_with_hidden_output(RandomMat(8, 2), 2, 1)
+           || test_rnn_layer_with_hidden_output(RandomMat(16, 8), 7, 1)
+           || test_rnn_layer_with_hidden_output(RandomMat(17, 8), 8, 1)
+           || test_rnn_layer_with_hidden_output(RandomMat(19, 15), 8, 1)
+           || test_rnn_layer_with_hidden_output(RandomMat(5, 16), 16, 1)
+           || test_rnn_layer_with_hidden_output(RandomMat(3, 16), 8, 1)
+           || test_rnn_layer_with_hidden_output(RandomMat(2, 5), 99, 1)
+           || test_rnn_layer_with_hidden_output(RandomMat(4, 2), 1, 0)
+           || test_rnn_layer_with_hidden_output(RandomMat(8, 2), 2, 0)
+           || test_rnn_layer_with_hidden_output(RandomMat(16, 8), 7, 0)
+           || test_rnn_layer_with_hidden_output(RandomMat(17, 8), 8, 0)
+           || test_rnn_layer_with_hidden_output(RandomMat(19, 15), 8, 0)
+           || test_rnn_layer_with_hidden_output(RandomMat(5, 16), 16, 0)
+           || test_rnn_layer_with_hidden_output(RandomMat(3, 16), 8, 0)
+           || test_rnn_layer_with_hidden_output(RandomMat(2, 5), 17, 0);
 }
 
 static int test_rnn_2()