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

[Snehasish Kumar via llvm-commits]

================
@@ -0,0 +1,214 @@
+//===- DataAccessProf.h - Data access profile format support ---------*- C++
+//-*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support to construct and use data access profiles.
+//
+// For the original RFC of this pass please see
+// https://discourse.llvm.org/t/rfc-profile-guided-static-data-partitioning/83744
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_PROFILEDATA_DATAACCESSPROF_H_
+#define LLVM_PROFILEDATA_DATAACCESSPROF_H_
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/DenseMapInfoVariant.h"
+#include "llvm/ADT/MapVector.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ProfileData/InstrProf.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/StringSaver.h"
+
+#include <cstdint>
+#include <optional>
+#include <variant>
+
+namespace llvm {
+
+namespace data_access_prof {
+
+/// The location of data in the source code. Used by profile lookup API.
+struct SourceLocation {
+  SourceLocation(StringRef FileNameRef, uint32_t Line)
+      : FileName(FileNameRef.str()), Line(Line) {}
+  /// The filename where the data is located.
+  std::string FileName;
+  /// The line number in the source code.
+  uint32_t Line;
+};
+
+namespace internal {
----------------
snehasish wrote:

Can the contents of the internal namespace (i.e. the ref variants) be moved to the .cpp file?

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