[llvm] [memprof] Fix IndexedMemProfRecord::clear (PR #118533)

[Snehasish Kumar via llvm-commits]

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@@ -416,7 +416,10 @@ struct IndexedMemProfRecord {
   // the last entry in the list with the same function GUID.
   llvm::SmallVector<CallStackId> CallSiteIds;
 
-  void clear() { AllocSites.clear(); }
+  void clear() {
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snehasish wrote:

An more durable alternative to this:
`*this = IndexedMemProfRecord();`

Up to you if you want to adopt it.

https://github.com/llvm/llvm-project/pull/118533