[llvm] [LAA] Move scalable vector check into `getStrideFromAddRec()` (PR #154013)

[Benjamin Maxwell via llvm-commits]

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@@ -0,0 +1,32 @@
+; RUN: opt -mtriple=aarch64-none-elf -mattr=+sve2 -O2 -disable-output
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MacDue wrote:

Tidied up the test a little and moved it over to `scalable-vector-regression-tests.ll` :+1: 

https://github.com/llvm/llvm-project/pull/154013