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

[Snehasish Kumar via llvm-commits]

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@@ -206,9 +222,52 @@ template <> struct MappingTraits<memprof::GUIDMemProfRecordPair> {
   }
 };
 
+template <> struct MappingTraits<data_access_prof::SourceLocation> {
+  static void mapping(IO &Io, data_access_prof::SourceLocation &Loc) {
+    Io.mapOptional("FileName", Loc.FileName);
+    Io.mapOptional("Line", Loc.Line);
+  }
+};
+
+template <> struct MappingTraits<data_access_prof::DataAccessProfRecord> {
+  static void mapping(IO &Io, data_access_prof::DataAccessProfRecord &Rec) {
+    if (Io.outputting()) {
+      if (std::holds_alternative<std::string>(Rec.SymHandle)) {
+        Io.mapOptional("Symbol", std::get<std::string>(Rec.SymHandle));
+      } else {
+        Io.mapOptional("Hash", std::get<uint64_t>(Rec.SymHandle));
+      }
+    } else {
+      std::string SymName;
+      uint64_t Hash = 0;
+      Io.mapOptional("Symbol", SymName);
+      Io.mapOptional("Hash", Hash);
+      if (!SymName.empty()) {
+        Rec.SymHandle = SymName;
+      } else {
+        Rec.SymHandle = Hash;
+      }
+    }
+
+    Io.mapOptional("Locations", Rec.Locations);
+  }
+};
+
+template <> struct MappingTraits<memprof::YamlDataAccessProfData> {
+  static void mapping(IO &Io, memprof::YamlDataAccessProfData &Data) {
+    Io.mapOptional("SampledRecords", Data.Records);
+    Io.mapOptional("KnownColdSymbols", Data.KnownColdSymbols);
+    Io.mapOptional("KnownColdHashes", Data.KnownColdHashes);
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snehasish wrote:

If this is the cstr hash, then maybe make it clearer by naming it KnownColdStrHash?

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