[llvm] [SLP] NFC. Refactor getSameOpcode and reduce for loop iterations. (PR #122241)

[Alexey Bataev via llvm-commits]

alexey-bataev wrote:

> Hi @HanKuanChen and @alexey-bataev ,
> 
> The following starts crashing with this "NFC" patch:
> 
> ```
> opt -passes="slp-vectorizer" bbi-103405.ll -S -o /dev/null -mtriple=thumb7 -mcpu=swift
> ```
> 
> [bbi-103405.ll.gz](https://github.com/user-attachments/files/18573264/bbi-103405.ll.gz)


Fixed in a1ab5b4c87256ce7e99d6fd4bd0c62641e6ce853


https://github.com/llvm/llvm-project/pull/122241