[llvm] [PGO] Add llvm.loop.estimated_trip_count metadata (PR #152775)

[Joel E. Denny via llvm-commits]

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@@ -0,0 +1,61 @@
+; Test "llvm.loop.estimated_trip_count" validation
+
+; DEFINE: %{RUN} = opt -passes=verify %t -disable-output 2>&1 | \
+; DEFINE:   FileCheck %s -allow-empty -check-prefix
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jdenny-ornl wrote:

> The idiomatic way to do this is split-file.

Originally I coded it that way, but I did not like the repetition of the boilerplate code.  I prefer the way the current version isolates what is unique about each case.

> Tests that don't actually contain the tested code are inconvenient.

As a general rule of thumb, sure.  But what is the inconvenience in this test file?

https://github.com/llvm/llvm-project/pull/152775