diff --git a/llvm/include/llvm/ADT/bit.h b/llvm/include/llvm/ADT/bit.h
index d6e33c3e6133a..2ca9b43519740 100644
--- a/llvm/include/llvm/ADT/bit.h
+++ b/llvm/include/llvm/ADT/bit.h
@@ -161,7 +161,7 @@ template <typename T> [[nodiscard]] int countr_zero(T Val) {
     return std::numeric_limits<T>::digits;
 
   // Use the intrinsic if available.
-  if constexpr (sizeof(T) == 4) {
+  if constexpr (sizeof(T) <= 4) {
 #if __has_builtin(__builtin_ctz) || defined(__GNUC__)
     return __builtin_ctz(Val);
 #elif defined(_MSC_VER)
diff --git a/llvm/unittests/ADT/BitTest.cpp b/llvm/unittests/ADT/BitTest.cpp
index 2377ce3b78261..88ae36c44bdb9 100644
--- a/llvm/unittests/ADT/BitTest.cpp
+++ b/llvm/unittests/ADT/BitTest.cpp
@@ -297,6 +297,14 @@ TEST(BitTest, CountrZero) {
   EXPECT_EQ(1, llvm::countr_zero(NZ16));
   EXPECT_EQ(1, llvm::countr_zero(NZ32));
   EXPECT_EQ(1, llvm::countr_zero(NZ64));
+
+  EXPECT_EQ(0, llvm::countr_zero(uint8_t(1)));
+  EXPECT_EQ(3, llvm::countr_zero(uint8_t(8)));
+  EXPECT_EQ(7, llvm::countr_zero(uint8_t(128)));
+
+  EXPECT_EQ(0, llvm::countr_zero(uint16_t(1)));
+  EXPECT_EQ(8, llvm::countr_zero(uint16_t(256)));
+  EXPECT_EQ(15, llvm::countr_zero(uint16_t(32768)));
 }
 
 TEST(BitTest, CountlOne) {