[llvm] [ThinLTO] Allow importing based on a workload definition (PR #74545)

[Teresa Johnson via llvm-commits]

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@@ -1,67 +1,153 @@
+; Set up
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teresajohnson wrote:

Nit: add brief comment at the top about what this is testing (e.g. the workload based importing via -thinlto-workload-def.

Also suggest moving the current m1.ll, m2.ll, and m3.ll code to the end so that all the test RUN lines and checks are at the top.

https://github.com/llvm/llvm-project/pull/74545