[llvm] [StaticDataLayout][PGO] Add profile format for static data layout, and the classes to operate on the profiles. (PR #138170)

[Teresa Johnson via llvm-commits]

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@@ -57,6 +57,8 @@ class MapVector {
     return std::move(Vector);
   }
 
+  ArrayRef<value_type> getArrayRef() const { return Vector; }
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teresajohnson wrote:

Probably put this into a separate prep patch with a test in llvm/unittests/ADT/MapVectorTest.cpp.

https://github.com/llvm/llvm-project/pull/138170