[llvm] [StaticDataLayout][PGO]Implement reader and writer change for data access profiles (PR #139997)

[Mingming Liu via llvm-commits]

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@@ -390,6 +419,14 @@ Error IndexedMemProfReader::deserializeRadixTreeBased(
       /*Payload=*/Start + RecordPayloadOffset,
       /*Base=*/Start, memprof::RecordLookupTrait(Version, Schema)));
 
+  if (DataAccessProfOffset > RecordTableOffset) {
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mingmingl-llvm wrote:

I realized checking the length of data access profile payload before creating the class or calling its 'deserialize' method will do it. Since it's towards the end of the working week and the change is ~20 lines , I took the liberty to go ahead :)

I'm open to make the length field more general (e.g., recording the length of the total memprof profile will make it useful when there are new payloads after data access profiles) and would like to hear thoughts on it.

https://github.com/llvm/llvm-project/pull/139997