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

[Sumanth Gundapaneni 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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sgundapa 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.
2.  To verify the verify the loop-align. 

If we are not able to pipeline this loop, sooner or later it is going to show up in hexagon nightly tests as regression. 



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