[llvm] [AArch64]: Refactor target parser to use Bitset. (PR #65423)

[via llvm-commits]

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@@ -69,6 +70,26 @@ std::string FormatExtensionFlags(uint64_t Flags) {
   return llvm::join(Features, ", ");
 }
 
+std::string SerializeExtensionFlags(Bitset<AArch64::AEK_EXTENSIONS_MAX> Flags) {
+  static_assert((AArch64::AEK_EXTENSIONS_MAX % 4 == 0),
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sdesmalen-arm wrote:

Rather than forcing assumptions on AEK_EXTENSIONS_MAX, I think you should do explicit up-rounding here instead.

https://github.com/llvm/llvm-project/pull/65423