.. meta::
  :description: Learn about the operations supported in hipDNN.
  :keywords: hipDNN, ROCm, operations

.. _plugin-support:

************************
hipDNN operation support
************************

hipDNN operations are implemented through plugins. Each plugin provides its own set of supported operations. For detailed information about what operations are available, refer to the plugin-specific documentation.

Plugins
=======

- :ref:`miopen-provider`: Provides integration with AMD's `MIOpen library <https://rocm.docs.amd.com/projects/MIOpen/en/latest/index.html>`_ for GPU-accelerated deep learning operations.

  - Convolution operations (Forward, Dgrad, Wgrad)
  - Batchnorm operations (Training, Backward, Inference)
  - Fused operation graphs

- :ref:`hipblaslt`: Provides integration with AMD's `hipBLASLt library <https://rocm.docs.amd.com/projects/hipBLASLt/en/latest/index.html>`_ that provides optimized GEMM operations.


.. _dimension-layouts:

Tensor dimensions and layouts
=============================

Tensor dimension ordering in hipDNN is *operation-specific*, following the same conventions as
PyTorch and cuDNN. The *memory layout* (channel-first vs channel-last) is always controlled by
strides and stride order, not by the order of the tensor dimension vector that always holds values as [N,C,H,W] or [N,C,D,H,W].

For example, memory arranged as NCHW corresponds to stride order {3,2,1,0} (W is the most tightly packed), and NDHWC corresponds to stride order {4,0,3,2,1} (C is the most tightly packed).
Use the ``TensorLayout`` constants and the ``generateStrides()`` utility to compute strides for common layouts.

The following tables outline the specific dimensions and layouts for supported hipDNN operations.

Convolution
-----------

.. list-table::
   :widths: 3 3 3 5
   :header-rows: 1

   * - Tensor
     - Shape (4D)
     - Shape (5D)
     - Description
   * - Input (x)
     - ``(N, C, H, W)``
     - ``(N, C, D, H, W)``
     - Batch, channels, spatial dims
   * - Weights (w)
     - ``(K, C/groups, R, S)``
     - ``(K, C/groups, T, R, S)``
     - Output channels, input channels per group, kernel spatial dims
   * - Output (y)
     - ``(N, K, H_out, W_out)``
     - ``(N, K, D_out, H_out, W_out)``
     - Batch, output channels, output spatial dims
   * - Backward data output (dx)
     - ``(N, C, H, W)``
     - ``(N, C, D, H, W)``
     - Must match the original forward input ``x`` shape; set explicitly before graph validation/build
   * - Backward weights output (dw)
     - ``(K, C/groups, R, S)``
     - ``(K, C/groups, T, R, S)``
     - Must match the original forward weights ``w`` shape; set explicitly before graph validation/build

For convolution backward data and backward weights, hipDNN does not infer the ``dx`` or ``dw`` dimensions from the other tensors. Set ``dx`` to the original forward input shape and ``dw`` to the original forward weights shape before graph validation/build. The forward convolution spatial formula uses floor division, so multiple input or kernel shapes can produce the same ``dy`` shape; only output strides may be inferred once explicit output dimensions are present.

.. code:: cpp

  // Convolution example: dims always follow (N, C, spatial...) ordering
  auto x = TensorAttributes()
              .set_dim({1, 64, 28, 28})   // N=1, C=64, H=28, W=28
              .set_stride(generateStrides({1, 64, 28, 28}, TensorLayout::NHWC.strideOrder));

  auto w = TensorAttributes()
              .set_dim({128, 64, 3, 3})   // K=128, C=64, R=3, S=3
              .set_stride(generateStrides({128, 64, 3, 3}, TensorLayout::NHWC.strideOrder));

Batch normalization
-------------------

.. list-table::
   :widths: 3 3 5
   :header-rows: 1

   * - Tensor
     - Shape
     - Description
   * - Input (x)
     - ``(N, C, H, W)`` or ``(N, C, D, H, W)``
     - Same ordering as convolution
   * - Scale, Bias, Mean, Variance
     - ``(1, C, 1, 1)`` or ``(1, C, 1, 1, 1)``
     - Per-channel parameters
   * - Output (y)
     - Same as input
     - Shape preserved

Statistics are computed per-channel over the batch and spatial dimensions.

Layer normalization
-------------------

.. list-table::
   :widths: 3 3 5
   :header-rows: 1

   * - Tensor
     - Shape
     - Description
   * - Input (x)
     - ``(N, ...)``
     - Batch first, then feature dims
   * - Scale, Bias
     -  ``(1, ...)``
     - Batch dim = 1, remaining dims match input feature dims
   * - Mean, Inv variance
     - Stats dims
     - Batch dims from input, normalized dims = 1

Normalization is performed over the feature dimensions (all dims where scale > 1).

Matrix multiplication
---------------------

.. list-table::
   :widths: 3 3 5
   :header-rows: 1

   * - Tensor
     - Shape
     - Description
   * - A
     - ``(...batch, M, K)``
     - Leading batch dims, last two are matrix dims
   * - B
     - ``(...batch, K, N)``
     - K must match A's last dim
   * - C (output)
     - ``(...batch, M, N)``
     - Batch dims are broadcast

Batch dimensions support broadcasting (dims must be equal or divisible).

.. code:: cpp

  // Matmul example: A(batch, M, K) @ B(batch, K, N) -> C(batch, M, N)
  auto a = TensorAttributes()
              .set_dim({4, 128, 64})    // batch=4, M=128, K=64
              .set_stride({128*64, 64, 1});

  auto b = TensorAttributes()
              .set_dim({4, 64, 256})    // batch=4, K=64, N=256
              .set_stride({64*256, 256, 1});


Pointwise operations
--------------------

Pointwise operations (ReLU, Sigmoid, Add, Mul, and so on) are *dimension-agnostic* — they accept
tensors of any shape. For binary and ternary operations, inputs are broadcast using NumPy-style
broadcasting rules (dimensions compared right-to-left; compatible if equal or 1).