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

[Arthur Eubanks via llvm-commits]

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

this appears in lots of tests, it should work on windows

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