[llvm] [ADT] Refactor Bitset to Be More Constexpr-Usable and Add More Member Functions (PR #172062)

[Jiachen Yuan via llvm-commits]

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@@ -41,6 +45,11 @@ class Bitset {
   using StorageType = std::array<BitWord, NumWords>;
   StorageType Bits{};
 
+  constexpr void maskLastWord() {
+    if constexpr (RemainderNumBits != 0)
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JiachenYuan wrote:

Removed just now. Thanks!

https://github.com/llvm/llvm-project/pull/172062