llvm · kazutakahirata · Nov 3, 2025 · Oct 14, 2025
diff --git a/llvm/include/llvm/ADT/APFloat.h b/llvm/include/llvm/ADT/APFloat.h
@@ -152,7 +152,7 @@ class APFloatBase {
   static constexpr unsigned integerPartWidth = APInt::APINT_BITS_PER_WORD;
 
   /// A signed type to represent a floating point numbers unbiased exponent.
-  typedef int32_t ExponentType;
+  using ExponentType = int32_t;
 
   /// \name Floating Point Semantics.
   /// @{
@@ -938,8 +938,8 @@ LLVM_ABI DoubleAPFloat frexp(const DoubleAPFloat &X, int &Exp, roundingMode);
 // This is a interface class that is currently forwarding functionalities from
 // detail::IEEEFloat.
 class APFloat : public APFloatBase {
-  typedef detail::IEEEFloat IEEEFloat;
-  typedef detail::DoubleAPFloat DoubleAPFloat;
+  using IEEEFloat = detail::IEEEFloat;
+  using DoubleAPFloat = detail::DoubleAPFloat;
 
   static_assert(std::is_standard_layout<IEEEFloat>::value);
 

diff --git a/llvm/include/llvm/ADT/APInt.h b/llvm/include/llvm/ADT/APInt.h
@@ -77,7 +77,7 @@ inline APInt operator-(APInt);
 ///
 class [[nodiscard]] APInt {
 public:
-  typedef uint64_t WordType;
+  using WordType = uint64_t;
 
   /// Byte size of a word.
   static constexpr unsigned APINT_WORD_SIZE = sizeof(WordType);

diff --git a/llvm/include/llvm/ADT/BitVector.h b/llvm/include/llvm/ADT/BitVector.h
@@ -99,7 +99,7 @@ template <typename BitVectorT> class const_set_bits_iterator_impl {
 };
 
 class BitVector {
-  typedef uintptr_t BitWord;
+  using BitWord = uintptr_t;
 
   enum { BITWORD_SIZE = (unsigned)sizeof(BitWord) * CHAR_BIT };
 
@@ -147,8 +147,8 @@ class BitVector {
     }
   };
 
-  typedef const_set_bits_iterator_impl<BitVector> const_set_bits_iterator;
-  typedef const_set_bits_iterator set_iterator;
+  using const_set_bits_iterator = const_set_bits_iterator_impl<BitVector>;
+  using set_iterator = const_set_bits_iterator;
 
   const_set_bits_iterator set_bits_begin() const {
     return const_set_bits_iterator(*this);

diff --git a/llvm/include/llvm/ADT/GenericSSAContext.h b/llvm/include/llvm/ADT/GenericSSAContext.h
@@ -25,7 +25,7 @@ template <typename, bool> class DominatorTreeBase;
 template <typename> class SmallVectorImpl;
 
 namespace Intrinsic {
-typedef unsigned ID;
+using ID = unsigned;
 }
 
 // Specializations of this template should provide the types used by the

diff --git a/llvm/include/llvm/ADT/STLExtras.h b/llvm/include/llvm/ADT/STLExtras.h
@@ -1516,8 +1516,8 @@ template <class Iterator, class RNG>
 void shuffle(Iterator first, Iterator last, RNG &&g) {
   // It would be better to use a std::uniform_int_distribution,
   // but that would be stdlib dependent.
-  typedef
-      typename std::iterator_traits<Iterator>::difference_type difference_type;
+  using difference_type =
+      typename std::iterator_traits<Iterator>::difference_type;
   for (auto size = last - first; size > 1; ++first, (void)--size) {
     difference_type offset = g() % size;
     // Avoid self-assignment due to incorrect assertions in libstdc++

diff --git a/llvm/include/llvm/ADT/ilist.h b/llvm/include/llvm/ADT/ilist.h
@@ -108,21 +108,21 @@ template <typename Ty> struct ilist_traits<const Ty> {};
 /// list.
 template <class IntrusiveListT, class TraitsT>
 class iplist_impl : public TraitsT, IntrusiveListT {
-  typedef IntrusiveListT base_list_type;
+  using base_list_type = IntrusiveListT;
 
 public:
-  typedef typename base_list_type::pointer pointer;
-  typedef typename base_list_type::const_pointer const_pointer;
-  typedef typename base_list_type::reference reference;
-  typedef typename base_list_type::const_reference const_reference;
-  typedef typename base_list_type::value_type value_type;
-  typedef typename base_list_type::size_type size_type;
-  typedef typename base_list_type::difference_type difference_type;
-  typedef typename base_list_type::iterator iterator;
-  typedef typename base_list_type::const_iterator const_iterator;
-  typedef typename base_list_type::reverse_iterator reverse_iterator;
-  typedef
-      typename base_list_type::const_reverse_iterator const_reverse_iterator;
+  using pointer = typename base_list_type::pointer;
+  using const_pointer = typename base_list_type::const_pointer;
+  using reference = typename base_list_type::reference;
+  using const_reference = typename base_list_type::const_reference;
+  using value_type = typename base_list_type::value_type;
+  using size_type = typename base_list_type::size_type;
+  using difference_type = typename base_list_type::difference_type;
+  using iterator = typename base_list_type::iterator;
+  using const_iterator = typename base_list_type::const_iterator;
+  using reverse_iterator = typename base_list_type::reverse_iterator;
+  using const_reverse_iterator =
+      typename base_list_type::const_reverse_iterator;
 
 private:
   static bool op_less(const_reference L, const_reference R) { return L < R; }

diff --git a/llvm/include/llvm/ADT/ilist_node_options.h b/llvm/include/llvm/ADT/ilist_node_options.h
@@ -58,8 +58,8 @@ namespace ilist_detail {
 template <bool IsExplicit> struct explicitness {
   static const bool is_explicit = IsExplicit;
 };
-typedef explicitness<true> is_explicit;
-typedef explicitness<false> is_implicit;
+using is_explicit = explicitness<true>;
+using is_implicit = explicitness<false>;
 
 /// Check whether an option is valid.
 ///
@@ -103,12 +103,12 @@ struct is_valid_option<ilist_sentinel_tracking<EnableSentinelTracking>>
 template <class... Options> struct extract_tag;
 template <class Tag, class... Options>
 struct extract_tag<ilist_tag<Tag>, Options...> {
-  typedef Tag type;
+  using type = Tag;
 };
 template <class Option1, class... Options>
 struct extract_tag<Option1, Options...> : extract_tag<Options...> {};
 template <> struct extract_tag<> {
-  typedef void type;
+  using type = void;
 };
 template <class Tag> struct is_valid_option<ilist_tag<Tag>> : std::true_type {};
 
@@ -134,11 +134,13 @@ struct is_valid_option<ilist_iterator_bits<IteratorBits>> : std::true_type {};
 template <class... Options> struct extract_parent;
 template <class ParentTy, class... Options>
 struct extract_parent<ilist_parent<ParentTy>, Options...> {
-  typedef ParentTy type;
+  using type = ParentTy;
 };
 template <class Option1, class... Options>
 struct extract_parent<Option1, Options...> : extract_parent<Options...> {};
-template <> struct extract_parent<> { typedef void type; };
+template <> struct extract_parent<> {
+  using type = void;
+};
 template <class ParentTy>
 struct is_valid_option<ilist_parent<ParentTy>> : std::true_type {};
 
@@ -154,28 +156,27 @@ struct check_options : std::conjunction<is_valid_option<Options>...> {};
 template <class T, bool EnableSentinelTracking, bool IsSentinelTrackingExplicit,
           class TagT, bool HasIteratorBits, class ParentTy>
 struct node_options {
-  typedef T value_type;
-  typedef T *pointer;
-  typedef T &reference;
-  typedef const T *const_pointer;
-  typedef const T &const_reference;
+  using value_type = T;
+  using pointer = T *;
+  using reference = T &;
+  using const_pointer = const T *;
+  using const_reference = const T &;
 
   static const bool enable_sentinel_tracking = EnableSentinelTracking;
   static const bool is_sentinel_tracking_explicit = IsSentinelTrackingExplicit;
   static const bool has_iterator_bits = HasIteratorBits;
-  typedef TagT tag;
-  typedef ParentTy parent_ty;
-  typedef ilist_node_base<enable_sentinel_tracking, parent_ty> node_base_type;
-  typedef ilist_base<enable_sentinel_tracking, parent_ty> list_base_type;
+  using tag = TagT;
+  using parent_ty = ParentTy;
+  using node_base_type = ilist_node_base<enable_sentinel_tracking, parent_ty>;
+  using list_base_type = ilist_base<enable_sentinel_tracking, parent_ty>;
 };
 
 template <class T, class... Options> struct compute_node_options {
-  typedef node_options<T, extract_sentinel_tracking<Options...>::value,
-                       extract_sentinel_tracking<Options...>::is_explicit,
-                       typename extract_tag<Options...>::type,
-                       extract_iterator_bits<Options...>::value,
-                       typename extract_parent<Options...>::type>
-      type;
+  using type = node_options<T, extract_sentinel_tracking<Options...>::value,
+                            extract_sentinel_tracking<Options...>::is_explicit,
+                            typename extract_tag<Options...>::type,
+                            extract_iterator_bits<Options...>::value,
+                            typename extract_parent<Options...>::type>;
 };
 
 } // end namespace ilist_detail

diff --git a/llvm/unittests/ADT/APFloatTest.cpp b/llvm/unittests/ADT/APFloatTest.cpp
@@ -10118,7 +10118,7 @@ TEST(APFloatTest, Float4E2M1FNToFloat) {
 }
 
 TEST(APFloatTest, AddOrSubtractSignificand) {
-  typedef detail::IEEEFloatUnitTestHelper Helper;
+  using Helper = detail::IEEEFloatUnitTestHelper;
   // Test cases are all combinations of:
   // {equal exponents, LHS larger exponent, RHS larger exponent}
   // {equal significands, LHS larger significand, RHS larger significand}

diff --git a/llvm/unittests/ADT/BitVectorTest.cpp b/llvm/unittests/ADT/BitVectorTest.cpp
@@ -21,7 +21,7 @@ template <typename T>
 class BitVectorTest : public ::testing::Test { };
 
 // Test both BitVector and SmallBitVector with the same suite of tests.
-typedef ::testing::Types<BitVector, SmallBitVector> BitVectorTestTypes;
+using BitVectorTestTypes = ::testing::Types<BitVector, SmallBitVector>;
 TYPED_TEST_SUITE(BitVectorTest, BitVectorTestTypes, );
 
 TYPED_TEST(BitVectorTest, TrivialOperation) {
@@ -857,7 +857,7 @@ TYPED_TEST(BitVectorTest, BinOps) {
   EXPECT_FALSE(B.anyCommon(A));
 }
 
-typedef std::vector<std::pair<int, int>> RangeList;
+using RangeList = std::vector<std::pair<int, int>>;
 
 template <typename VecType>
 static inline VecType createBitVector(uint32_t Size,

diff --git a/llvm/unittests/ADT/BreadthFirstIteratorTest.cpp b/llvm/unittests/ADT/BreadthFirstIteratorTest.cpp
@@ -21,7 +21,7 @@ using namespace llvm;
 namespace llvm {
 
 TEST(BreadthFristIteratorTest, Basic) {
-  typedef bf_iterator<Graph<4>> BFIter;
+  using BFIter = bf_iterator<Graph<4>>;
 
   Graph<4> G;
   G.AddEdge(0, 1);
@@ -46,7 +46,7 @@ TEST(BreadthFristIteratorTest, Basic) {
 }
 
 TEST(BreadthFristIteratorTest, Cycle) {
-  typedef bf_iterator<Graph<4>> BFIter;
+  using BFIter = bf_iterator<Graph<4>>;
 
   Graph<4> G;
   G.AddEdge(0, 1);

diff --git a/llvm/unittests/ADT/DAGDeltaAlgorithmTest.cpp b/llvm/unittests/ADT/DAGDeltaAlgorithmTest.cpp
@@ -15,7 +15,7 @@ using namespace llvm;
 
 namespace {
 
-typedef DAGDeltaAlgorithm::edge_ty edge_ty;
+using edge_ty = DAGDeltaAlgorithm::edge_ty;
 
 class FixedDAGDeltaAlgorithm : public DAGDeltaAlgorithm {
   changeset_ty FailingSet;

diff --git a/llvm/unittests/ADT/DenseMapTest.cpp b/llvm/unittests/ADT/DenseMapTest.cpp
@@ -129,18 +129,17 @@ typename T::mapped_type *const DenseMapTest<T>::dummy_value_ptr = nullptr;
 
 // Register these types for testing.
 // clang-format off
-typedef ::testing::Types<DenseMap<uint32_t, uint32_t>,
-                         DenseMap<uint32_t *, uint32_t *>,
-                         DenseMap<CtorTester, CtorTester, CtorTesterMapInfo>,
-                         DenseMap<EnumClass, uint32_t>,
-                         DenseMap<std::optional<uint32_t>, uint32_t>,
-                         SmallDenseMap<uint32_t, uint32_t>,
-                         SmallDenseMap<uint32_t *, uint32_t *>,
-                         SmallDenseMap<CtorTester, CtorTester, 4,
-                                       CtorTesterMapInfo>,
-                         SmallDenseMap<EnumClass, uint32_t>,
-                         SmallDenseMap<std::optional<uint32_t>, uint32_t>
-                         > DenseMapTestTypes;
+using DenseMapTestTypes = ::testing::Types<
+    DenseMap<uint32_t, uint32_t>,
+    DenseMap<uint32_t *, uint32_t *>,
+    DenseMap<CtorTester, CtorTester, CtorTesterMapInfo>,
+    DenseMap<EnumClass, uint32_t>,
+    DenseMap<std::optional<uint32_t>, uint32_t>,
+    SmallDenseMap<uint32_t, uint32_t>,
+    SmallDenseMap<uint32_t *, uint32_t *>,
+    SmallDenseMap<CtorTester, CtorTester, 4, CtorTesterMapInfo>,
+    SmallDenseMap<EnumClass, uint32_t>,
+    SmallDenseMap<std::optional<uint32_t>, uint32_t>>;
 // clang-format on
 
 TYPED_TEST_SUITE(DenseMapTest, DenseMapTestTypes, );

diff --git a/llvm/unittests/ADT/DenseSetTest.cpp b/llvm/unittests/ADT/DenseSetTest.cpp
@@ -96,13 +96,13 @@ template <typename T> class DenseSetTest : public testing::Test {
 };
 
 // Register these types for testing.
-typedef ::testing::Types<DenseSet<unsigned, TestDenseSetInfo>,
-                         const DenseSet<unsigned, TestDenseSetInfo>,
-                         SmallDenseSet<unsigned, 1, TestDenseSetInfo>,
-                         SmallDenseSet<unsigned, 4, TestDenseSetInfo>,
-                         const SmallDenseSet<unsigned, 4, TestDenseSetInfo>,
-                         SmallDenseSet<unsigned, 64, TestDenseSetInfo>>
-    DenseSetTestTypes;
+using DenseSetTestTypes =
+    ::testing::Types<DenseSet<unsigned, TestDenseSetInfo>,
+                     const DenseSet<unsigned, TestDenseSetInfo>,
+                     SmallDenseSet<unsigned, 1, TestDenseSetInfo>,
+                     SmallDenseSet<unsigned, 4, TestDenseSetInfo>,
+                     const SmallDenseSet<unsigned, 4, TestDenseSetInfo>,
+                     SmallDenseSet<unsigned, 64, TestDenseSetInfo>>;
 TYPED_TEST_SUITE(DenseSetTest, DenseSetTestTypes, );
 
 TYPED_TEST(DenseSetTest, Constructor) {

diff --git a/llvm/unittests/ADT/DepthFirstIteratorTest.cpp b/llvm/unittests/ADT/DepthFirstIteratorTest.cpp
@@ -21,7 +21,7 @@ using namespace llvm;
 namespace llvm {
 
 template <typename T> struct CountedSet {
-  typedef typename SmallPtrSet<T, 4>::iterator iterator;
+  using iterator = typename SmallPtrSet<T, 4>::iterator;
 
   SmallPtrSet<T, 4> S;
   int InsertVisited = 0;
@@ -44,8 +44,8 @@ template <typename T> class df_iterator_storage<CountedSet<T>, true> {
 };
 
 TEST(DepthFirstIteratorTest, ActuallyUpdateIterator) {
-  typedef CountedSet<Graph<3>::NodeType *> StorageT;
-  typedef df_iterator<Graph<3>, StorageT, true> DFIter;
+  using StorageT = CountedSet<Graph<3>::NodeType *>;
+  using DFIter = df_iterator<Graph<3>, StorageT, true>;
 
   Graph<3> G;
   G.AddEdge(0, 1);

diff --git a/llvm/unittests/ADT/IListBaseTest.cpp b/llvm/unittests/ADT/IListBaseTest.cpp
@@ -19,13 +19,14 @@ template <typename T> class IListBaseTest : public ::testing::Test {};
 class Parent;
 
 // Test variants with the same test.
-typedef ::testing::Types<ilist_base<false, void>, ilist_base<true, void>, ilist_base<false, Parent*>, ilist_base<true, Parent*>>
-    IListBaseTestTypes;
+using IListBaseTestTypes =
+    ::testing::Types<ilist_base<false, void>, ilist_base<true, void>,
+                     ilist_base<false, Parent *>, ilist_base<true, Parent *>>;
 TYPED_TEST_SUITE(IListBaseTest, IListBaseTestTypes, );
 
 TYPED_TEST(IListBaseTest, insertBeforeImpl) {
-  typedef TypeParam list_base_type;
-  typedef typename list_base_type::node_base_type node_base_type;
+  using list_base_type = TypeParam;
+  using node_base_type = typename list_base_type::node_base_type;
 
   node_base_type S, A, B;
 
@@ -51,8 +52,8 @@ TYPED_TEST(IListBaseTest, insertBeforeImpl) {
 }
 
 TYPED_TEST(IListBaseTest, removeImpl) {
-  typedef TypeParam list_base_type;
-  typedef typename list_base_type::node_base_type node_base_type;
+  using list_base_type = TypeParam;
+  using node_base_type = typename list_base_type::node_base_type;
 
   node_base_type S, A, B;
 
@@ -80,8 +81,8 @@ TYPED_TEST(IListBaseTest, removeImpl) {
 }
 
 TYPED_TEST(IListBaseTest, removeRangeImpl) {
-  typedef TypeParam list_base_type;
-  typedef typename list_base_type::node_base_type node_base_type;
+  using list_base_type = TypeParam;
+  using node_base_type = typename list_base_type::node_base_type;
 
   node_base_type S, A, B, C, D;
 
@@ -106,8 +107,8 @@ TYPED_TEST(IListBaseTest, removeRangeImpl) {
 }
 
 TYPED_TEST(IListBaseTest, removeRangeImplAllButSentinel) {
-  typedef TypeParam list_base_type;
-  typedef typename list_base_type::node_base_type node_base_type;
+  using list_base_type = TypeParam;
+  using node_base_type = typename list_base_type::node_base_type;
 
   node_base_type S, A, B;
 
@@ -126,8 +127,8 @@ TYPED_TEST(IListBaseTest, removeRangeImplAllButSentinel) {
 }
 
 TYPED_TEST(IListBaseTest, transferBeforeImpl) {
-  typedef TypeParam list_base_type;
-  typedef typename list_base_type::node_base_type node_base_type;
+  using list_base_type = TypeParam;
+  using node_base_type = typename list_base_type::node_base_type;
 
   node_base_type S1, S2, A, B, C, D, E;
 

diff --git a/llvm/unittests/ADT/IListIteratorTest.cpp b/llvm/unittests/ADT/IListIteratorTest.cpp
@@ -141,10 +141,10 @@ TEST(IListIteratorTest, ReverseConstructor) {
   L.insert(L.end(), B);
 
   // Save typing.
-  typedef simple_ilist<Node>::iterator iterator;
-  typedef simple_ilist<Node>::reverse_iterator reverse_iterator;
-  typedef simple_ilist<Node>::const_iterator const_iterator;
-  typedef simple_ilist<Node>::const_reverse_iterator const_reverse_iterator;
+  using iterator = simple_ilist<Node>::iterator;
+  using reverse_iterator = simple_ilist<Node>::reverse_iterator;
+  using const_iterator = simple_ilist<Node>::const_iterator;
+  using const_reverse_iterator = simple_ilist<Node>::const_reverse_iterator;
 
   // Check conversion values.
   EXPECT_EQ(L.begin(), iterator(L.rend()));