[llvm] [clang][modules] Move `SLocEntry` search into `ASTReader` (PR #66966)

[Ben Langmuir via llvm-commits]

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@@ -2261,43 +2261,68 @@ template <typename... Refs> struct enumerator_result<std::size_t, Refs...> {
   mutable range_reference_tuple Storage;
 };
 
-/// Infinite stream of increasing 0-based `size_t` indices.
-struct index_stream {
-  struct iterator : iterator_facade_base<iterator, std::forward_iterator_tag,
-                                         const iterator> {
-    iterator &operator++() {
-      assert(Index != std::numeric_limits<std::size_t>::max() &&
-             "Attempting to increment end iterator");
-      ++Index;
-      return *this;
-    }
+struct index_iterator
+    : llvm::iterator_facade_base<index_iterator,
+                                 std::random_access_iterator_tag, std::size_t,
+                                 std::ptrdiff_t> {
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benlangmuir wrote:

ptrdiff_t is the default

https://github.com/llvm/llvm-project/pull/66966