[llvm] [VPlan] Simplify extract-lane from same single-scalar. (PR #226102)

[via llvm-commits]

llvmorg-github-actions[bot] wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-transforms

Author: Florian Hahn (fhahn)

<details>
<summary>Changes</summary>

Generalize extract-lane(idx, single-scalar) -> single-scalar to also apply if there are multiple vectors to extract and all values are the same single-scalar.

---
Full diff: https://github.com/llvm/llvm-project/pull/226102.diff


3 Files Affected:

- (modified) llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp (+10-14) 
- (modified) llvm/test/Transforms/LoopVectorize/early-exit-live-out-extract-lane.ll (+2-24) 
- (modified) llvm/test/Transforms/LoopVectorize/narrow-to-single-scalar.ll (+1-12) 


``````````diff
The server is unavailable at this time. Please wait a few minutes before you try again.
``````````

</details>


https://github.com/llvm/llvm-project/pull/226102