[Docs] Add operator fusion architecture documentation#19394
[Docs] Add operator fusion architecture documentation#19394MasterJH5574 merged 1 commit intoapache:mainfrom
Conversation
![gemini-code-assist[bot]](https://avatars.githubusercontent.com/in/956858?s=60&v=4){kind=small}
There was a problem hiding this comment.
Code Review
This pull request introduces a comprehensive architectural document for Operator Fusion in TVM Relax, detailing the automatic fusion mechanism using post-dominator analysis, pattern-based fusion for external backends, and the TIR merging process. The documentation covers operator pattern classification, the multi-phase fusion algorithm, and provides a source code map for developers. A review comment suggests enhancing the documentation by mentioning that the maximum fusion depth limit is configurable via pass options.
| - **Reduction** (``kCommReduce``) ops never initiate fusion — they act as sinks only. Elementwise | ||
| and broadcast producers can fuse *into* a reduction, but a reduction cannot fuse forward. | ||
| - **Opaque** ops are fusion barriers. | ||
| - A group cannot exceed ``kMaxFusedOps`` (256) nodes or the maximum function argument count. |
There was a problem hiding this comment.
It would be beneficial to mention that the kMaxFusedOps limit is configurable via the relax.FuseOps.max_depth pass configuration option, as this provides users with control over the fusion granularity.
2 participants
as per title