diff --git a/llvm/unittests/Support/TargetParserTest.cpp b/llvm/unittests/Support/TargetParserTest.cpp
--- a/llvm/unittests/Support/TargetParserTest.cpp
+++ b/llvm/unittests/Support/TargetParserTest.cpp
@@ -1713,6 +1713,8 @@
               AArch64::convertV9toV8(AArch64::ArchKind::ARMV9_2A));
   EXPECT_EQ(AArch64::ArchKind::ARMV8_8A,
               AArch64::convertV9toV8(AArch64::ArchKind::ARMV9_3A));
+  EXPECT_EQ(AArch64::ArchKind::ARMV8_9A,
+              AArch64::convertV9toV8(AArch64::ArchKind::ARMV9_4A));
 }
 
 TEST(TargetParserTest, AArch64ArchExtFeature) {