[libunwind] [libunwind] Add initial ARM64EC support (PR #138583)

[Martin Storsjö via cfe-commits]

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@@ -1181,7 +1228,9 @@ DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
 
 #endif
 
+#ifndef __arm64ec__
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mstorsjo wrote:

Can you explain why this has to be ifdeffed out here?

https://github.com/llvm/llvm-project/pull/138583