ConvTranspose Fusion Patterns

Overview

oneDNN supports both floating-point and quantized ConvTranspose fusion patterns to optimize performance and reduce memory bandwidth requirements. This document describes the supported floating-point fusion patterns for ConvTranspose. For quantized ConvTranspose fusion patterns, refer to Quantized ConvTranspose Fusion Patterns for more details.

Pattern Structure

oneDNN defines floating-point ConvTranspose fusion patterns as follows. The blue nodes are required when defining a ConvTranspose fusion pattern while the brown nodes are optional.

1. ConvTranspose Operation : Performs transposed convolution between the src and weights tensors. The bias tensor is optional. See the ConvTranspose operation in the Graph API for more details.

2. Epilogue Subgraph : Optional and can include the following operations:

   • BiasAdd operation.

   • Binary and Unary operations: refer to the Note in Fusion Patterns.

   Combination Rules:

   

   • BiasAdd : If present, must be the first op in the epilogue subgraph and can only appear once.

   • N=20, 0 to 20 Binary or Unary operations are supported in the epilogue subgraph.

Data Types

oneDNN supports the following combinations of data types for src, weights, bias and dst:

src	weights	bias	dst
f32,bf16,f16	f32,bf16,f16	f32,bf16,f16	f32,bf16,f16

The definition of the data types and support status on different CPU and GPU platforms follow the general description in the Data Types Guide.

Implementation Notes

Post-binary Add operations in the epilogue subgraph support in-place operations when the post-binary Add is the last operation in the epilogue subgraph and the dst output shape is identical and data type size is the same as the binary Add input. In case of an in-place operation, the original input data will be overwritten. Use in-place operations whenever possible for performance.