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

[via llvm-commits]

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@@ -684,9 +686,64 @@ PrintIRInstrumentation::~PrintIRInstrumentation() {
   assert(ModuleDescStack.empty() && "ModuleDescStack is not empty at exit");
 }
 
-void PrintIRInstrumentation::pushModuleDesc(StringRef PassID, Any IR) {
+static SmallString<32> getIRDisplayName(Any IR) {
+
+  auto hashName = [](StringRef name) {
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kyulee-com wrote:

> Note hashing is not guaranteed to be stable between executions

I thought hashing strings are stable unless the seed for hashing is changed. If so, can we use a stable hash like `stable_hash_combine_string`? Unless the module name is changed, I'd like to get a stable file name.

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