[clang] [llvm] [mlir] [llvm][DebugInfo][NFC] Abstract DICompileUnit::SourceLanguage to allow alternate DWARF SourceLanguage encoding (PR #162255)

[Adrian Prantl via llvm-commits]

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@@ -66,6 +66,44 @@ namespace dwarf {
 enum Tag : uint16_t;
 }
 
+/// Wrapper structure that holds a language name and its version.
+///
+/// Some debug-info formats, particularly DWARF, distniguish between
+/// language codes that include the version name and codes that don't.
+/// DISourceLanguageName may hold either of these.
+///
+class DISourceLanguageName {
+  /// Language name.
+  /// If \ref Version is not std::nullopt, then this name
+  /// is version independent (i.e., doesn't include the language
+  /// version in its name).
+  uint16_t Name;
+
+  /// Language version. The version scheme is language
+  /// dependent.
+  std::optional<uint32_t> Version;
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adrian-prantl wrote:

possibly flip the order between these?

https://github.com/llvm/llvm-project/pull/162255