[llvm] [BOLT][DWARF][NFC] Refactor GDB Index into a new file (PR #94405)

[Alexander Yermolovich via llvm-commits]

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@@ -0,0 +1,60 @@
+//===-- bolt/Core/GDBIndex.h - GDB Index 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 declaration of classes required for generation of
+/// .gdb_index section.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef BOLT_CORE_GDB_INDEX_H
+#define BOLT_CORE_GDB_INDEX_H
+
+#include "bolt/Core/BinaryContext.h"
+#include <vector>
+
+namespace llvm {
+namespace bolt {
+
+class GDBIndex {
+public:
+  /// Contains information about TU so we can write out correct entries in GDB
+  /// index.
+  struct GDBIndexTUEntry {
+    uint64_t UnitOffset;
+    uint64_t TypeHash;
+    uint64_t TypeDIERelativeOffset;
+  };
+
+private:
+  BinaryContext &BC;
+
+  /// Entries for GDB Index Types CU List
+  using GDBIndexTUEntryType = std::vector<GDBIndexTUEntry>;
+  GDBIndexTUEntryType GDBIndexTUEntryVector;
+
+public:
+  GDBIndex(BinaryContext &BC) : BC(BC) {}
+
+  /// Adds an GDBIndexTUEntry if .gdb_index section exists.
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ayermolo wrote:

Right now it always happens. Maybe in follow up commit let's change it.
Meanwhile change comment to reflect current behavior.

https://github.com/llvm/llvm-project/pull/94405