[clang] [llvm] [X86] Support apxf in attribute target (PR #184078)

[Mikołaj Piróg via cfe-commits]

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@@ -179,6 +179,31 @@ bool X86TargetInfo::initFeatureMap(
       continue;
     }
 
+    // Expand apxf to the individual APX features
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mikolaj-pirog wrote:

I believe it shouldn't. I realize it's quite awkward to not have symmetry between -no-apxf and -apxf but at the same time I believe -no option gives us lesser mandate to exclude features than positive option. I just would be incredibly confused if -no-apxf didn't disable everything

https://github.com/llvm/llvm-project/pull/184078