[ADT] Add an initializer_list constructor to {Small,}DenseSet.

Reviewers: timshen

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D25629

llvm-svn: 284433

2 files changed, 21 insertions, 0 deletions

diff --git a/llvm/include/llvm/ADT/DenseSet.h b/llvm/include/llvm/ADT/DenseSet.h
index 21f7dfa3321..b25d3b7cba6 100644
--- a/llvm/include/llvm/ADT/DenseSet.h
+++ b/llvm/include/llvm/ADT/DenseSet.h
@@ -15,6 +15,7 @@
 #define LLVM_ADT_DENSESET_H
 
 #include "llvm/ADT/DenseMap.h"
+#include <initializer_list>
 
 namespace llvm {
 
@@ -55,6 +56,11 @@ public:
 
   explicit DenseSetImpl(unsigned InitialReserve = 0) : TheMap(InitialReserve) {}
 
+  DenseSetImpl(std::initializer_list<ValueT> Elems)
+      : DenseSetImpl(Elems.size()) {
+    insert(Elems.begin(), Elems.end());
+  }
+
   bool empty() const { return TheMap.empty(); }
   size_type size() const { return TheMap.size(); }
   size_t getMemorySize() const { return TheMap.getMemorySize(); }
diff --git a/llvm/unittests/ADT/DenseSetTest.cpp b/llvm/unittests/ADT/DenseSetTest.cpp
index 8397c60a97c..4d5a82902f0 100644
--- a/llvm/unittests/ADT/DenseSetTest.cpp
+++ b/llvm/unittests/ADT/DenseSetTest.cpp
@@ -64,6 +64,21 @@ typedef ::testing::Types<DenseSet<unsigned, TestDenseSetInfo>,
     DenseSetTestTypes;
 TYPED_TEST_CASE(DenseSetTest, DenseSetTestTypes);
 
+TYPED_TEST(DenseSetTest, InitializerList) {
+  TypeParam set({1, 2, 1, 4});
+  EXPECT_EQ(3u, set.size());
+  EXPECT_EQ(1u, set.count(1));
+  EXPECT_EQ(1u, set.count(2));
+  EXPECT_EQ(1u, set.count(4));
+  EXPECT_EQ(0u, set.count(3));
+}
+
+TYPED_TEST(DenseSetTest, EmptyInitializerList) {
+  TypeParam set({});
+  EXPECT_EQ(0u, set.size());
+  EXPECT_EQ(0u, set.count(0));
+}
+
 TYPED_TEST(DenseSetTest, FindAsTest) {
   auto &set = this->Set;
   // Size tests