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

[Snehasish Kumar via llvm-commits]

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@@ -41,6 +41,8 @@ namespace data_access_prof {
 struct SourceLocation {
   SourceLocation(StringRef FileNameRef, uint32_t Line)
       : FileName(FileNameRef.str()), Line(Line) {}
+
+  SourceLocation() {}
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snehasish wrote:

I tried removing this ctor and realized it's needed for the yaml conversion. Can you add a comment?

Also same for the DataAccessProfRecord below.

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