[clang] [Clang] speed up -Wassign-enum via enumerator caching (PR #176560)

[via cfe-commits]

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@@ -3522,6 +3522,10 @@ class Sema final : public SemaBase {
   /// attribute.
   mutable llvm::DenseMap<const EnumDecl *, llvm::APInt> FlagBitsCache;
 
+  /// A cache of enumerator values for enums checked by -Wassign-enum.
+  mutable llvm::DenseMap<const EnumDecl *, llvm::SmallVector<llvm::APSInt, 64>>
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Sirraide wrote:

I think we can just drop the `mutable`

https://github.com/llvm/llvm-project/pull/176560