[libunwind] [libunwind][Haiku] Improve support (PR #115462)

[Jérôme Duval via cfe-commits]

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@@ -2749,6 +2755,63 @@ int UnwindCursor<A, R>::stepThroughSigReturn(Registers_arm64 &) {
   _isSignalFrame = true;
   return UNW_STEP_SUCCESS;
 }
+#elif defined(_LIBUNWIND_TARGET_HAIKU) && defined(_LIBUNWIND_TARGET_X86_64)
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korli wrote:

Done.

https://github.com/llvm/llvm-project/pull/115462