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diff --git a/linux-x64/clang/include/llvm/ADT/SmallSet.h b/linux-x64/clang/include/llvm/ADT/SmallSet.h
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+//===- llvm/ADT/SmallSet.h - 'Normally small' sets --------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the SmallSet class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ADT_SMALLSET_H
+#define LLVM_ADT_SMALLSET_H
+
+#include "llvm/ADT/None.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/Compiler.h"
+#include <cstddef>
+#include <functional>
+#include <set>
+#include <utility>
+
+namespace llvm {
+
+/// SmallSet - This maintains a set of unique values, optimizing for the case
+/// when the set is small (less than N). In this case, the set can be
+/// maintained with no mallocs. If the set gets large, we expand to using an
+/// std::set to maintain reasonable lookup times.
+///
+/// Note that this set does not provide a way to iterate over members in the
+/// set.
+template <typename T, unsigned N, typename C = std::less<T>>
+class SmallSet {
+ /// Use a SmallVector to hold the elements here (even though it will never
+ /// reach its 'large' stage) to avoid calling the default ctors of elements
+ /// we will never use.
+ SmallVector<T, N> Vector;
+ std::set<T, C> Set;
+
+ using VIterator = typename SmallVector<T, N>::const_iterator;
+ using mutable_iterator = typename SmallVector<T, N>::iterator;
+
+ // In small mode SmallPtrSet uses linear search for the elements, so it is
+ // not a good idea to choose this value too high. You may consider using a
+ // DenseSet<> instead if you expect many elements in the set.
+ static_assert(N <= 32, "N should be small");
+
+public:
+ using size_type = size_t;
+
+ SmallSet() = default;
+
+ LLVM_NODISCARD bool empty() const {
+ return Vector.empty() && Set.empty();
+ }
+
+ size_type size() const {
+ return isSmall() ? Vector.size() : Set.size();
+ }
+
+ /// count - Return 1 if the element is in the set, 0 otherwise.
+ size_type count(const T &V) const {
+ if (isSmall()) {
+ // Since the collection is small, just do a linear search.
+ return vfind(V) == Vector.end() ? 0 : 1;
+ } else {
+ return Set.count(V);
+ }
+ }
+
+ /// insert - Insert an element into the set if it isn't already there.
+ /// Returns true if the element is inserted (it was not in the set before).
+ /// The first value of the returned pair is unused and provided for
+ /// partial compatibility with the standard library self-associative container
+ /// concept.
+ // FIXME: Add iterators that abstract over the small and large form, and then
+ // return those here.
+ std::pair<NoneType, bool> insert(const T &V) {
+ if (!isSmall())
+ return std::make_pair(None, Set.insert(V).second);
+
+ VIterator I = vfind(V);
+ if (I != Vector.end()) // Don't reinsert if it already exists.
+ return std::make_pair(None, false);
+ if (Vector.size() < N) {
+ Vector.push_back(V);
+ return std::make_pair(None, true);
+ }
+
+ // Otherwise, grow from vector to set.
+ while (!Vector.empty()) {
+ Set.insert(Vector.back());
+ Vector.pop_back();
+ }
+ Set.insert(V);
+ return std::make_pair(None, true);
+ }
+
+ template <typename IterT>
+ void insert(IterT I, IterT E) {
+ for (; I != E; ++I)
+ insert(*I);
+ }
+
+ bool erase(const T &V) {
+ if (!isSmall())
+ return Set.erase(V);
+ for (mutable_iterator I = Vector.begin(), E = Vector.end(); I != E; ++I)
+ if (*I == V) {
+ Vector.erase(I);
+ return true;
+ }
+ return false;
+ }
+
+ void clear() {
+ Vector.clear();
+ Set.clear();
+ }
+
+private:
+ bool isSmall() const { return Set.empty(); }
+
+ VIterator vfind(const T &V) const {
+ for (VIterator I = Vector.begin(), E = Vector.end(); I != E; ++I)
+ if (*I == V)
+ return I;
+ return Vector.end();
+ }
+};
+
+/// If this set is of pointer values, transparently switch over to using
+/// SmallPtrSet for performance.
+template <typename PointeeType, unsigned N>
+class SmallSet<PointeeType*, N> : public SmallPtrSet<PointeeType*, N> {};
+
+} // end namespace llvm
+
+#endif // LLVM_ADT_SMALLSET_H