[compiler-rt] [libcxxabi] [libunwind] [runtimes][PAC] Harden unwinding when possible (#138571) (PR #143230)

[Oliver Hunt via llvm-commits]

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@@ -93,6 +98,13 @@ class _LIBUNWIND_HIDDEN Registers_x86 {
   uint32_t  getEDI() const         { return _registers.__edi; }
   void      setEDI(uint32_t value) { _registers.__edi = value; }
 
+  typedef uint32_t reg_t;
+  typedef uint32_t link_reg_t;
+  void loadAndAuthenticateLinkRegister(reg_t srcLinkRegister,
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ojhunt wrote:

yeah, especially as it's clearly difficult to ensure with local builds that you've got every other platform correct, and then it's make-work for every other platform.

https://github.com/llvm/llvm-project/pull/143230