BiasAddBackward {#dev_guide_op_biasaddbackward}
===============================================

## General

BiasAddBackward operation computes the gradients on the bias tensor for
BiasAdd operator. This op accumulates all the values from \f$\diffdst\f$ into
the channel dimension, the axis depends on the layout of \src tensor.

## Operation attributes

Attribute Name | Description | Value Type |Supported Values | Required or Optional
-- | -- | --| --|--
[data_format](@ref dnnl::graph::op::attr::data_format) | Controls how to interpret the shape of `diff_dst` and `diff_bias`. |string |`NCX` , `NXC` (default)  | Optional

## Execution arguments

The inputs and outputs must be provided according to below index order when
constructing an operation.

### Inputs

Index | Argument Name | Required or Optional
-- | -- | --
0|`diff_dst` | Required

### Outputs

Index | Argument Name | Required or Optional
-- | -- | --
0|`diff_bias` | Required

## Supported data types

BiasAddBackward operation supports the following data type combinations.

diff_dst  | diff_bias
---- | -------
f32  | f32
bf16 | bf16
f16  | f16
