[llvm] [MachinePipeliner] Remove UB from tests (NFC) (PR #123169)

[Ryotaro Kasuga via llvm-commits]

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@@ -0,0 +1,267 @@
+# RUN: llc -mtriple=hexagon -mcpu=hexagonv73 -O2 -mattr=+hvxv73,hvx-length64b \
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kasuga-fj wrote:

> Thanks for fixing these tests. AFAIK, this test is from a core benchmark which Hexagon backend really cares.
The correct thing here to do, is to split this test in two tests.
>
> 1. To verify that we are software pipelining.
> 1. To verify the verify the loop-align.

I'd like to separate this test in the future, but when I do, I will submit another PR.

https://github.com/llvm/llvm-project/pull/123169