1 files changed, 32 insertions, 0 deletions
diff --git a/llvm/unittests/ADT/APIntTest.cpp b/llvm/unittests/ADT/APIntTest.cpp
index 331b3997071..06b4d77cb8b 100644
--- a/llvm/unittests/ADT/APIntTest.cpp
+++ b/llvm/unittests/ADT/APIntTest.cpp
@@ -1659,6 +1659,38 @@ TEST(APIntTest, isShiftedMask) {
   }
 }
 
+// Test that self-move works, but only when we're using MSVC.
+#if defined(_MSC_VER)
+#if defined(__clang__)
+// Disable the pragma warning from versions of Clang without -Wself-move
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunknown-pragmas"
+// Disable the warning that triggers on exactly what is being tested.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wself-move"
+#endif
+TEST(APIntTest, SelfMoveAssignment) {
+  APInt X(32, 0xdeadbeef);
+  X = std::move(X);
+  EXPECT_EQ(32u, X.getBitWidth());
+  EXPECT_EQ(0xdeadbeefULL, X.getLimitedValue());
+
+  uint64_t Bits[] = {0xdeadbeefdeadbeefULL, 0xdeadbeefdeadbeefULL};
+  APInt Y(128, Bits);
+  Y = std::move(Y);
+  EXPECT_EQ(128u, Y.getBitWidth());
+  EXPECT_EQ(~0ULL, Y.getLimitedValue());
+  const uint64_t *Raw = Y.getRawData();
+  EXPECT_EQ(2u, Y.getNumWords());
+  EXPECT_EQ(0xdeadbeefdeadbeefULL, Raw[0]);
+  EXPECT_EQ(0xdeadbeefdeadbeefULL, Raw[1]);
+}
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#pragma clang diagnostic pop
+#endif
+#endif // _MSC_VER
+
 TEST(APIntTest, reverseBits) {
   EXPECT_EQ(1, APInt(1, 1).reverseBits());
   EXPECT_EQ(0, APInt(1, 0).reverseBits());