[clang] [llvm] Generate `DW_AT_RUST_short_backtrace` attributes for `DISubprogram` nodes (PR #123683)

[via llvm-commits]

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@@ -125,6 +125,13 @@ class DITypeRefArray {
   iterator end() const { return N ? iterator(N->op_end()) : iterator(); }
 };
 
+/// DWARF-like extension attribute for setting short backtrace debuginfo.
+enum class ShortBacktraceAttr {
+  SkipFrame = 0,
+  StartShortBacktrace = 1,
+  EndShortBacktrace = 2,
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DianQK wrote:

Could you add some documents? I'm not clear why `StartShortBacktrace` and `EndShortBacktrace` cannot be replaced by `SkipFrame`? IIUC, we can add `SkipFrame` annotation to all frames/functions that between `StartShortBacktrace` and `EndShortBacktrace`.

https://github.com/llvm/llvm-project/pull/123683