[llvm] Add option to dump IR to files instead of stderr (PR #66412)

[Nuri Amari via llvm-commits]

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@@ -0,0 +1,57 @@
+; RUN: mkdir -p %t/logs
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NuriAmari wrote:

It passes the windows CI on this PR, is that assurance enough?

https://github.com/llvm/llvm-project/pull/66412