[clang] [llvm] [AArch64] Add -mlr-for-calls-only to replace the now removed -ffixed-x30 flag. (PR #98073)

[Eli Friedman via cfe-commits]

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@@ -4917,6 +4917,9 @@ foreach i = {1-31} in
   def ffixed_x#i : Flag<["-"], "ffixed-x"#i>, Group<m_Group>,
     HelpText<"Reserve the x"#i#" register (AArch64/RISC-V only)">;
 
+def mlr_for_calls_only : Flag<["-"], "mlr-for-calls-only">, Group<m_aarch64_Features_Group>,
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efriedma-quic wrote:

Name seems okay.

https://github.com/llvm/llvm-project/pull/98073