[clang] [llvm] [AIX] Add -msave-reg-params to save arguments to stack (PR #97524)

[Hubert Tong via cfe-commits]

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@@ -5040,6 +5040,10 @@ def mspe : Flag<["-"], "mspe">, Group<m_ppc_Features_Group>;
 def mno_spe : Flag<["-"], "mno-spe">, Group<m_ppc_Features_Group>;
 def mefpu2 : Flag<["-"], "mefpu2">, Group<m_ppc_Features_Group>;
 } // let Flags = [TargetSpecific]
+def msave_reg_params : Flag<["-"], "msave-reg-params">, Group<m_Group>,
+  Visibility<[ClangOption, CC1Option]>,
+  HelpText<"Save arguments passed by registers to stack">,
+  MarshallingInfoFlag<CodeGenOpts<"SaveRegParams">>;
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hubert-reinterpretcast wrote:

There should be diagnostics (and tests for such) when the option is specified and the implementation has not been done for the target.

https://github.com/llvm/llvm-project/pull/97524