[llvm] [clang] [X86] Support CFE flags for APX features (PR #74199)

[Phoebe Wang via cfe-commits]

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@@ -5999,6 +5999,12 @@ def mno_gather : Flag<["-"], "mno-gather">, Group<m_Group>,
                  HelpText<"Disable generation of gather instructions in auto-vectorization(x86 only)">;
 def mno_scatter : Flag<["-"], "mno-scatter">, Group<m_Group>,
                   HelpText<"Disable generation of scatter instructions in auto-vectorization(x86 only)">;
+def mapx_features_EQ : CommaJoined<["-"], "mapx-features=">, Group<m_x86_Features_Group>,
+    HelpText<"Enable features of APX">, Values<"egpr,push2pop2,ppx,ndd,ccmp,cf">;
+def mno_apx_features_EQ : CommaJoined<["-"], "mno-apx-features=">, Group<m_x86_Features_Group>,
+    HelpText<"Disable features of APX">, Values<"egpr,push2pop2,ppx,ndd,ccmp,cf">;
+def mapxf : Flag<["-"], "mapxf">, Alias<mapx_features_EQ>, AliasArgs<["egpr","push2pop2","ppx"]>;
+def mno_apxf : Flag<["-"], "mno-apxf">, Alias<mno_apx_features_EQ>, AliasArgs<["egpr","push2pop2","ppx"]>;
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phoebewang wrote:

The commit message mentions `alias of -m[no-]apx-features=< all APX features covered by CPUID APX_F>`, why only 3 here?

https://github.com/llvm/llvm-project/pull/74199