[libunwind] [libunwind][arm64e] Mach-O Support unwinding PAuth_LR frames (PR #202772)

[Daniil Kovalev via cfe-commits]

================
@@ -1917,6 +1917,28 @@ class _LIBUNWIND_HIDDEN Registers_arm64 {
 #endif
     _registers.__pc = value;
   }
+  __attribute__((target("pauth-lr"))) void setIPPAuthLR(uint64_t value,
+                                                        uint64_t signing_pc) {
+#if defined(_LIBUNWIND_TARGET_AARCH64_AUTHENTICATED_UNWINDING)
+#if __has_builtin(__builtin_ptrauth_auth_with_pc_and_resign)
+    value = (uint64_t)ptrauth_auth_with_pc_and_resign(
+        (void *)value, ptrauth_key_process_dependent_code, (void *)getSP(),
+        (void *)signing_pc, ptrauth_key_return_address, &_registers.__pc);
----------------
kovdan01 wrote:

Nit: are casts needed for `getSP()` and `signing_pc`?

https://github.com/llvm/llvm-project/pull/202772