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

[Arthur Eubanks via llvm-commits]

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

capitalize, and enum class is better

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