[lld] [LLD][ELF] add bp-* options in ELF (PR #120514)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,36 @@
+//===- BPSectionOrderer.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 uses Balanced Partitioning to order sections to improve startup
+/// time and compressed size.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLD_ELF_BPSECTION_ORDERER_H
+#define LLD_ELF_BPSECTION_ORDERER_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/StringRef.h"
+
+namespace lld::elf {
+struct Ctx;
+class InputSectionBase;
+
+/// Run Balanced Partitioning to find the optimal function and data order to
+/// improve startup time and compressed size.
+///
+/// It is important that .subsections_via_symbols is used to ensure functions
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MaskRay wrote:

Please don't blindly comments. ELF doesn't use subsections_via_symbols

https://github.com/llvm/llvm-project/pull/120514