[llvm] [clang] [SPARC] Consume `tune-cpu` directive in the backend (PR #77195)

[Sergei Barannikov via cfe-commits]

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@@ -5119,7 +5119,7 @@ def module_file_info : Flag<["-"], "module-file-info">, Flags<[]>,
   HelpText<"Provide information about a particular module file">;
 def mthumb : Flag<["-"], "mthumb">, Group<m_Group>;
 def mtune_EQ : Joined<["-"], "mtune=">, Group<m_Group>,
-  HelpText<"Only supported on AArch64, PowerPC, RISC-V, SystemZ, and X86">;
+  HelpText<"Only supported on AArch64, PowerPC, RISC-V, SPARC, SystemZ, and X86">;
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s-barannikov wrote:

Is this the only required change at the clang side?
Which component is responsible for emitting errors on invalid / incompatible -mtune options?
I guess we need some test for this.


https://github.com/llvm/llvm-project/pull/77195