diff --git a/llvm/include/llvm/ADT/DenseMap.h b/llvm/include/llvm/ADT/DenseMap.h
--- a/llvm/include/llvm/ADT/DenseMap.h
+++ b/llvm/include/llvm/ADT/DenseMap.h
@@ -924,6 +924,9 @@
     this->insert(I, E);
   }
 
+  SmallDenseMap(std::initializer_list<typename BaseT::value_type> Vals)
+      : SmallDenseMap(Vals.begin(), Vals.end()) {}
+
   ~SmallDenseMap() {
     this->destroyAll();
     deallocateBuckets();
diff --git a/llvm/unittests/ADT/DenseMapTest.cpp b/llvm/unittests/ADT/DenseMapTest.cpp
--- a/llvm/unittests/ADT/DenseMapTest.cpp
+++ b/llvm/unittests/ADT/DenseMapTest.cpp
@@ -547,6 +547,15 @@
   EXPECT_TRUE(map.find_as("d") == map.end());
 }
 
+TEST(DenseMapCustomTest, SmallDenseMapInitializerList) {
+  SmallDenseMap<int, int> M = {{0, 0}, {0, 1}, {1, 2}};
+  EXPECT_EQ(2u, M.size());
+  EXPECT_EQ(1u, M.count(0));
+  EXPECT_EQ(0, M[0]);
+  EXPECT_EQ(1u, M.count(1));
+  EXPECT_EQ(2, M[1]);
+}
+
 struct ContiguousDenseMapInfo {
   static inline unsigned getEmptyKey() { return ~0; }
   static inline unsigned getTombstoneKey() { return ~0U - 1; }