[libunwind] [Unwind][AArch64] Match sigreturn instructions in big endian (PR #167139)

[Jordan R AW via cfe-commits]

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@@ -58,6 +58,14 @@
 #include "RWMutex.hpp"
 #include "Unwind-EHABI.h"
 
+#if defined(__AARCH64EB__)
+#define MOVZ_X8_8B 0x681180d2
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ajordanr-google wrote:

Can you put the `movz x8, #0x8b` and `svc #0x0` comment up here to indicate what these mean at the definition. The names are definitely helpful, but knowing these are for checking for a trampoline is helpful.

https://github.com/llvm/llvm-project/pull/167139