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

[Arthur Eubanks via llvm-commits]

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@@ -0,0 +1,56 @@
+; RUN: rm -rf %t/logs
+
+; Basic dump before and after a single module pass
+
+; RUN: opt %s -disable-output -passes='no-op-module' -ir-dump-directory %t/logs -print-after=no-op-module -print-before=no-op-module
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aeubanks wrote:

the actual numbers should be consistent since they depend solely on the passes that run?

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