--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/unittests/ADT/IListTest.cpp	Thu Nov 30 18:00:49 2017 +0900
@@ -0,0 +1,276 @@
+//===- unittests/ADT/IListTest.cpp - ilist unit tests ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/ilist.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/ilist_node.h"
+#include "gtest/gtest.h"
+#include <ostream>
+
+using namespace llvm;
+
+namespace {
+
+struct Node : ilist_node<Node> {
+  int Value;
+
+  Node() {}
+  Node(int Value) : Value(Value) {}
+  Node(const Node&) = default;
+  ~Node() { Value = -1; }
+};
+
+TEST(IListTest, Basic) {
+  ilist<Node> List;
+  List.push_back(new Node(1));
+  EXPECT_EQ(1, List.back().Value);
+  EXPECT_EQ(nullptr, List.getPrevNode(List.back()));
+  EXPECT_EQ(nullptr, List.getNextNode(List.back()));
+
+  List.push_back(new Node(2));
+  EXPECT_EQ(2, List.back().Value);
+  EXPECT_EQ(2, List.getNextNode(List.front())->Value);
+  EXPECT_EQ(1, List.getPrevNode(List.back())->Value);
+
+  const ilist<Node> &ConstList = List;
+  EXPECT_EQ(2, ConstList.back().Value);
+  EXPECT_EQ(2, ConstList.getNextNode(ConstList.front())->Value);
+  EXPECT_EQ(1, ConstList.getPrevNode(ConstList.back())->Value);
+}
+
+TEST(IListTest, cloneFrom) {
+  Node L1Nodes[] = {Node(0), Node(1)};
+  Node L2Nodes[] = {Node(0), Node(1)};
+  ilist<Node> L1, L2, L3;
+
+  // Build L1 from L1Nodes.
+  L1.push_back(&L1Nodes[0]);
+  L1.push_back(&L1Nodes[1]);
+
+  // Build L2 from L2Nodes, based on L1 nodes.
+  L2.cloneFrom(L1, [&](const Node &N) { return &L2Nodes[N.Value]; });
+
+  // Add a node to L3 to be deleted, and then rebuild L3 by copying L1.
+  L3.push_back(new Node(7));
+  L3.cloneFrom(L1, [](const Node &N) { return new Node(N); });
+
+  EXPECT_EQ(2u, L1.size());
+  EXPECT_EQ(&L1Nodes[0], &L1.front());
+  EXPECT_EQ(&L1Nodes[1], &L1.back());
+  EXPECT_EQ(2u, L2.size());
+  EXPECT_EQ(&L2Nodes[0], &L2.front());
+  EXPECT_EQ(&L2Nodes[1], &L2.back());
+  EXPECT_EQ(2u, L3.size());
+  EXPECT_EQ(0, L3.front().Value);
+  EXPECT_EQ(1, L3.back().Value);
+
+  // Don't free nodes on the stack.
+  L1.clearAndLeakNodesUnsafely();
+  L2.clearAndLeakNodesUnsafely();
+}
+
+TEST(IListTest, SpliceOne) {
+  ilist<Node> List;
+  List.push_back(new Node(1));
+
+  // The single-element splice operation supports noops.
+  List.splice(List.begin(), List, List.begin());
+  EXPECT_EQ(1u, List.size());
+  EXPECT_EQ(1, List.front().Value);
+  EXPECT_TRUE(std::next(List.begin()) == List.end());
+
+  // Altenative noop. Move the first element behind itself.
+  List.push_back(new Node(2));
+  List.push_back(new Node(3));
+  List.splice(std::next(List.begin()), List, List.begin());
+  EXPECT_EQ(3u, List.size());
+  EXPECT_EQ(1, List.front().Value);
+  EXPECT_EQ(2, std::next(List.begin())->Value);
+  EXPECT_EQ(3, List.back().Value);
+}
+
+TEST(IListTest, SpliceSwap) {
+  ilist<Node> L;
+  Node N0(0);
+  Node N1(1);
+  L.insert(L.end(), &N0);
+  L.insert(L.end(), &N1);
+  EXPECT_EQ(0, L.front().Value);
+  EXPECT_EQ(1, L.back().Value);
+
+  L.splice(L.begin(), L, ++L.begin());
+  EXPECT_EQ(1, L.front().Value);
+  EXPECT_EQ(0, L.back().Value);
+
+  L.clearAndLeakNodesUnsafely();
+}
+
+TEST(IListTest, SpliceSwapOtherWay) {
+  ilist<Node> L;
+  Node N0(0);
+  Node N1(1);
+  L.insert(L.end(), &N0);
+  L.insert(L.end(), &N1);
+  EXPECT_EQ(0, L.front().Value);
+  EXPECT_EQ(1, L.back().Value);
+
+  L.splice(L.end(), L, L.begin());
+  EXPECT_EQ(1, L.front().Value);
+  EXPECT_EQ(0, L.back().Value);
+
+  L.clearAndLeakNodesUnsafely();
+}
+
+TEST(IListTest, UnsafeClear) {
+  ilist<Node> List;
+
+  // Before even allocating a sentinel.
+  List.clearAndLeakNodesUnsafely();
+  EXPECT_EQ(0u, List.size());
+
+  // Empty list with sentinel.
+  ilist<Node>::iterator E = List.end();
+  List.clearAndLeakNodesUnsafely();
+  EXPECT_EQ(0u, List.size());
+  // The sentinel shouldn't change.
+  EXPECT_TRUE(E == List.end());
+
+  // List with contents.
+  List.push_back(new Node(1));
+  ASSERT_EQ(1u, List.size());
+  Node *N = &*List.begin();
+  EXPECT_EQ(1, N->Value);
+  List.clearAndLeakNodesUnsafely();
+  EXPECT_EQ(0u, List.size());
+  ASSERT_EQ(1, N->Value);
+  delete N;
+
+  // List is still functional.
+  List.push_back(new Node(5));
+  List.push_back(new Node(6));
+  ASSERT_EQ(2u, List.size());
+  EXPECT_EQ(5, List.front().Value);
+  EXPECT_EQ(6, List.back().Value);
+}
+
+struct Empty {};
+TEST(IListTest, HasObsoleteCustomizationTrait) {
+  // Negative test for HasObsoleteCustomization.
+  static_assert(!ilist_detail::HasObsoleteCustomization<Empty, Node>::value,
+                "Empty has no customizations");
+}
+
+struct GetNext {
+  Node *getNext(Node *);
+};
+TEST(IListTest, HasGetNextTrait) {
+  static_assert(ilist_detail::HasGetNext<GetNext, Node>::value,
+                "GetNext has a getNext(Node*)");
+  static_assert(ilist_detail::HasObsoleteCustomization<GetNext, Node>::value,
+                "Empty should be obsolete because of getNext()");
+
+  // Negative test for HasGetNext.
+  static_assert(!ilist_detail::HasGetNext<Empty, Node>::value,
+                "Empty does not have a getNext(Node*)");
+}
+
+struct CreateSentinel {
+  Node *createSentinel();
+};
+TEST(IListTest, HasCreateSentinelTrait) {
+  static_assert(ilist_detail::HasCreateSentinel<CreateSentinel>::value,
+                "CreateSentinel has a getNext(Node*)");
+  static_assert(
+      ilist_detail::HasObsoleteCustomization<CreateSentinel, Node>::value,
+      "Empty should be obsolete because of createSentinel()");
+
+  // Negative test for HasCreateSentinel.
+  static_assert(!ilist_detail::HasCreateSentinel<Empty>::value,
+                "Empty does not have a createSentinel()");
+}
+
+struct NodeWithCallback : ilist_node<NodeWithCallback> {
+  int Value = 0;
+  bool IsInList = false;
+  bool WasTransferred = false;
+
+  NodeWithCallback() = default;
+  NodeWithCallback(int Value) : Value(Value) {}
+  NodeWithCallback(const NodeWithCallback &) = delete;
+};
+
+} // end namespace
+
+namespace llvm {
+template <> struct ilist_callback_traits<NodeWithCallback> {
+  void addNodeToList(NodeWithCallback *N) { N->IsInList = true; }
+  void removeNodeFromList(NodeWithCallback *N) { N->IsInList = false; }
+  template <class Iterator>
+  void transferNodesFromList(ilist_callback_traits &Other, Iterator First,
+                             Iterator Last) {
+    for (; First != Last; ++First) {
+      First->WasTransferred = true;
+      Other.removeNodeFromList(&*First);
+      addNodeToList(&*First);
+    }
+  }
+};
+} // end namespace llvm
+
+namespace {
+
+TEST(IListTest, addNodeToList) {
+  ilist<NodeWithCallback> L1, L2;
+  NodeWithCallback N(7);
+  ASSERT_FALSE(N.IsInList);
+  ASSERT_FALSE(N.WasTransferred);
+
+  L1.insert(L1.begin(), &N);
+  ASSERT_EQ(1u, L1.size());
+  ASSERT_EQ(&N, &L1.front());
+  ASSERT_TRUE(N.IsInList);
+  ASSERT_FALSE(N.WasTransferred);
+
+  L2.splice(L2.end(), L1);
+  ASSERT_EQ(&N, &L2.front());
+  ASSERT_TRUE(N.IsInList);
+  ASSERT_TRUE(N.WasTransferred);
+
+  L1.remove(&N);
+  ASSERT_EQ(0u, L1.size());
+  ASSERT_FALSE(N.IsInList);
+  ASSERT_TRUE(N.WasTransferred);
+}
+
+struct PrivateNode : private ilist_node<PrivateNode> {
+  friend struct llvm::ilist_detail::NodeAccess;
+
+  int Value = 0;
+
+  PrivateNode() = default;
+  PrivateNode(int Value) : Value(Value) {}
+  PrivateNode(const PrivateNode &) = delete;
+};
+
+TEST(IListTest, privateNode) {
+  // Instantiate various APIs to be sure they're callable when ilist_node is
+  // inherited privately.
+  ilist<PrivateNode> L;
+  PrivateNode N(7);
+  L.insert(L.begin(), &N);
+  ++L.begin();
+  (void)*L.begin();
+  (void)(L.begin() == L.end());
+
+  ilist<PrivateNode> L2;
+  L2.splice(L2.end(), L);
+  L2.remove(&N);
+}
+
+} // end namespace