.. index:: pair: page; LogSoftmaxBackward .. _doxid-dev_guide_op_logsoftmaxbackward: LogSoftmaxBackward ================== General ~~~~~~~ LogSoftmaxBackward operation computes gradient for LogSoftmax. Operation attributes ~~~~~~~~~~~~~~~~~~~~ ================================================================================================================= =================================================================================================================== =========== ========================================= ===================== Attribute Name Description Value Type Supported Values Required or Optional ================================================================================================================= =================================================================================================================== =========== ========================================= ===================== :ref:`axis ` Represents the axis of which the LogSoftmax is calculated. Negative value means counting dimensions from the back. s64 Arbitrary s64 value ( ``-1`` in 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 1 ``dst`` Required ====== ============== ===================== Outputs ------- ====== ============== ===================== Index Argument Name Required or Optional ====== ============== ===================== 0 ``diff_src`` Required ====== ============== ===================== Supported data types ~~~~~~~~~~~~~~~~~~~~ LogSoftmaxBackward operation supports the following data type combinations. ========= ===== ========= Diff_dst Dst Diff_src ========= ===== ========= f32 f32 f32 bf16 bf16 bf16 f16 f16 f16 ========= ===== ========= Implementation Notes ~~~~~~~~~~~~~~~~~~~~ LogSoftmaxBackward supports in-place operations, meaning that ``diff_dst`` can be used as both input and output (``diff_src``). In case of in-place operation, the original ``diff_dst`` data will be overwritten. This support is limited to cases when data types of ``diff_dst`` and ``diff_src`` are identical. Use in-place operations whenever possible for performance.