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

[Arthur Eubanks via llvm-commits]

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@@ -46,6 +46,24 @@ class PrintIRInstrumentation {
   void registerCallbacks(PassInstrumentationCallbacks &PIC);
 
 private:
+  enum class SuffixType {
+    Before,
+    After,
+    Invalidated,
+  };
+
+  struct PassRunDescriptor {
+    const Module *M;
+    SmallString<128> DumpIRFilename;
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aeubanks wrote:

`std::string` should be good enough unless you have performance data that this is better

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