[llvm] [GSYM] Callsites: Add data format support and loading from YAML (PR #109781)

[Kyungwoo Lee via llvm-commits]

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@@ -0,0 +1,188 @@
+//===- CallSiteInfo.h -------------------------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_DEBUGINFO_GSYM_CALLSITEINFO_H
+#define LLVM_DEBUGINFO_GSYM_CALLSITEINFO_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/DebugInfo/GSYM/ExtractRanges.h"
+#include "llvm/Support/YAMLParser.h"
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+namespace llvm {
+class DataExtractor;
+class raw_ostream;
+class StringTableBuilder;
+class CachedHashStringRef;
+
+namespace yaml {
+struct CallSiteYAML;
+struct FunctionYAML;
+struct FunctionsYAML;
+} // namespace yaml
+
+namespace gsym {
+class FileWriter;
+struct FunctionInfo;
+struct CallSiteInfo {
+  enum Flags : uint8_t {
+    None = 0,
+    // This flag specifies that the call site can only call a function within
+    // the same link unit as the call site.
+    InternalCall = 1 << 0,
+    // This flag specifies that the call site can only call a function outside
+    // the link unit that the call site is in.
+    ExternalCall = 1 << 1,
+  };
+
+  /// The return address of the call site.
+  uint64_t ReturnAddress;
----------------
kyulee-com wrote:

Let's just initialize it with a default value for the safety.
```suggestion
  uint64_t ReturnAddress = 0;
```

https://github.com/llvm/llvm-project/pull/109781