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

[Sebastian Neubauer via llvm-commits]

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@@ -46,6 +46,16 @@ class PrintIRInstrumentation {
   void registerCallbacks(PassInstrumentationCallbacks &PIC);
 
 private:
+  enum SuffixType {
+    before,
+    after,
+    invalidated,
+  };
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Flakebi wrote:

nit: I think this can be an `enum class` and all the types can be TitleCase (I think this is the prevailing style for new enums).

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