[llvm] [MachinePipeliner] Fix fragile tests (PR #123169)

[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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bcahoon wrote:

I think the original test is intended to verify both the pipeliner and the loop align pass.  For performance, the loop should  include 4 bundles and have the 32-byte alignment. If anything in the back-end causes that to not happen, then the test should fail. Though, it's not clear that is the intent given the name of the test. I'll add @sgundapa here, since he added the test. 

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