[llvm] Avoid need for SLocEntryLoaded BitVector (PR #67960)

[Vassil Vassilev via llvm-commits]

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@@ -103,6 +103,14 @@ template <typename T, size_t PageSize = 1024 / sizeof(T)> class PagedVector {
   /// Return the size of the vector.
   [[nodiscard]] size_t size() const { return Size; }
 
+  /// Return true if the element at `Index` belongs to a page which was already
+  /// materialized, i.e., had at least one element accessed.
+  [[nodiscard]] bool isMaterialized(size_t Index) const {
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vgvassilev wrote:

We should add a test case for this function.

https://github.com/llvm/llvm-project/pull/67960