[clang] [llvm] [Clang][AArch64] Command-line options for A-profile's Sign Return Address Hardening (PR #176171)

[Anatoly Trosinenko via cfe-commits]

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@@ -170,6 +170,11 @@ Makes programs 10x faster by doing Special New Thing.
 
 ### Changes to the AArch64 Backend
 
+* Added support for hardening return address signing against PACMAN attacks.
+  Functions with the `"sign-return-address-harden"="load-return-address"`
+  attribute perform a load of the return address before returning, reducing the
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atrosinenko wrote:

[nit] "load **from** the return address"

https://github.com/llvm/llvm-project/pull/176171