[clang] [compiler-rt] [llvm] [X86] Sync multiversion features with libgcc and refactor internal feature tables (PR #168750)

[Mikołaj Piróg via llvm-commits]

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@@ -181,8 +177,7 @@ enum ProcessorFeatures {
   // FEATURE_OSXSAVE,
   FEATURE_PCONFIG = 63,
   FEATURE_PKU,
-  FEATURE_PREFETCHWT1,
-  FEATURE_PRFCHW,
+  FEATURE_PRFCHW = 66,
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mikolaj-pirog wrote:

I believe we comment out features not supported by llvm but supported gcc. This feature is not supported by gcc, so no comment

https://github.com/llvm/llvm-project/pull/168750