[clang] [clang-tools-extra] [llvm] [libunwind] [libunwind] Replace process_vm_readv with SYS_rt_sigprocmask (PR #74791)

[Jordan R AW via cfe-commits]

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@@ -26,7 +26,7 @@
 __attribute__((naked)) void bad_unwind_info() {
 #if defined(__aarch64__)
   __asm__("// not using 0 because unwinder was already resilient to that\n"
-          "mov     x8, #4\n"
+          "mov     x8, #12\n"
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ajordanr-google wrote:

Note: changed this for an 8 byte alignment check, because `0x4 & 0x7` is `0x0`, whereas `0xC & 0x7` is `0x8`.

https://github.com/llvm/llvm-project/pull/74791