[lld] [lld][ELF] Extend profile guided function ordering to ELF binaries (PR #117514)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,77 @@
+//===- BPSectionOrdererBase.h ---------------------------------------------===//
+//
+// 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 defines the common interfaces which may be used by
+// BPSectionOrderer.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLD_COMMON_BP_SECTION_ORDERER_BASE_H
+#define LLD_COMMON_BP_SECTION_ORDERER_BASE_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/Support/xxhash.h"
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MaskRay wrote:

include <optional>

https://github.com/llvm/llvm-project/pull/117514