[llvm] Use std::optional instead of Optional

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716

35 files changed, 108 insertions, 113 deletions

diff --git a/llvm/include/llvm/ADT/BreadthFirstIterator.h b/llvm/include/llvm/ADT/BreadthFirstIterator.h
index cfeb7a7..41f3d8e 100644
--- a/llvm/include/llvm/ADT/BreadthFirstIterator.h
+++ b/llvm/include/llvm/ADT/BreadthFirstIterator.h
@@ -57,11 +57,11 @@ private:
   using ChildItTy = typename GT::ChildIteratorType;
 
   // First element is the node reference, second is the next child to visit.
-  using QueueElement = std::pair<NodeRef, Optional<ChildItTy>>;
+  using QueueElement = std::pair<NodeRef, std::optional<ChildItTy>>;
 
   // Visit queue - used to maintain BFS ordering.
-  // Optional<> because we need markers for levels.
-  std::queue<Optional<QueueElement>> VisitQueue;
+  // std::optional<> because we need markers for levels.
+  std::queue<std::optional<QueueElement>> VisitQueue;
 
   // Current level.
   unsigned Level = 0;
@@ -78,10 +78,10 @@ private:
   inline bf_iterator() = default;
 
   inline void toNext() {
-    Optional<QueueElement> Head = VisitQueue.front();
+    std::optional<QueueElement> Head = VisitQueue.front();
     QueueElement H = *Head;
     NodeRef Node = H.first;
-    Optional<ChildItTy> &ChildIt = H.second;
+    std::optional<ChildItTy> &ChildIt = H.second;
 
     if (!ChildIt)
       ChildIt.emplace(GT::child_begin(Node));
diff --git a/llvm/include/llvm/ADT/DepthFirstIterator.h b/llvm/include/llvm/ADT/DepthFirstIterator.h
index 04223d5f..4105a95 100644
--- a/llvm/include/llvm/ADT/DepthFirstIterator.h
+++ b/llvm/include/llvm/ADT/DepthFirstIterator.h
@@ -97,7 +97,7 @@ private:
   // First element is node reference, second is the 'next child' to visit.
   // The second child is initialized lazily to pick up graph changes during the
   // DFS.
-  using StackElement = std::pair<NodeRef, Optional<ChildItTy>>;
+  using StackElement = std::pair<NodeRef, std::optional<ChildItTy>>;
 
   // VisitStack - Used to maintain the ordering.  Top = current block
   std::vector<StackElement> VisitStack;
@@ -123,7 +123,7 @@ private:
   inline void toNext() {
     do {
       NodeRef Node = VisitStack.back().first;
-      Optional<ChildItTy> &Opt = VisitStack.back().second;
+      std::optional<ChildItTy> &Opt = VisitStack.back().second;
 
       if (!Opt)
         Opt.emplace(GT::child_begin(Node));
diff --git a/llvm/include/llvm/ADT/None.h b/llvm/include/llvm/ADT/None.h
index d55bd46..c497821 100644
--- a/llvm/include/llvm/ADT/None.h
+++ b/llvm/include/llvm/ADT/None.h
@@ -20,7 +20,7 @@
 #include <optional>
 
 namespace llvm {
-/// A simple null object to allow implicit construction of Optional<T>
+/// A simple null object to allow implicit construction of std::optional<T>
 /// and similar types without having to spell out the specialization's name.
 LLVM_DEPRECATED("Use std::nullopt_t instead", "std::nullopt_t")
 typedef std::nullopt_t NoneType;
diff --git a/llvm/include/llvm/BinaryFormat/Wasm.h b/llvm/include/llvm/BinaryFormat/Wasm.h
index eebd2aa..d185516 100644
--- a/llvm/include/llvm/BinaryFormat/Wasm.h
+++ b/llvm/include/llvm/BinaryFormat/Wasm.h
@@ -206,11 +206,11 @@ struct WasmSymbolInfo {
   uint8_t Kind;
   uint32_t Flags;
   // For undefined symbols the module of the import
-  Optional<StringRef> ImportModule;
+  std::optional<StringRef> ImportModule;
   // For undefined symbols the name of the import
-  Optional<StringRef> ImportName;
+  std::optional<StringRef> ImportName;
   // For symbols to be exported from the final module
-  Optional<StringRef> ExportName;
+  std::optional<StringRef> ExportName;
   union {
     // For function, table, or global symbols, the index in function, table, or
     // global index space.
diff --git a/llvm/include/llvm/DWP/DWP.h b/llvm/include/llvm/DWP/DWP.h
index f60f8cc..ff26140 100644
--- a/llvm/include/llvm/DWP/DWP.h
+++ b/llvm/include/llvm/DWP/DWP.h
@@ -44,7 +44,7 @@ struct InfoSectionUnitHeader {
 
   // dwo_id field. This resides in the header only if Version >= 5.
   // In earlier versions, it is read from DW_AT_GNU_dwo_id.
-  Optional<uint64_t> Signature = std::nullopt;
+  std::optional<uint64_t> Signature = std::nullopt;
 
   // Derived from the length of Length field.
   dwarf::DwarfFormat Format = dwarf::DwarfFormat::DWARF32;
diff --git a/llvm/include/llvm/Debuginfod/Debuginfod.h b/llvm/include/llvm/Debuginfod/Debuginfod.h
index df7fd9f..cd9cc3b 100644
--- a/llvm/include/llvm/Debuginfod/Debuginfod.h
+++ b/llvm/include/llvm/Debuginfod/Debuginfod.h
@@ -106,8 +106,8 @@ class DebuginfodCollection {
   sys::RWMutex DebugBinariesMutex;
   StringMap<std::string> DebugBinaries;
   Error findBinaries(StringRef Path);
-  Expected<Optional<std::string>> getDebugBinaryPath(object::BuildIDRef);
-  Expected<Optional<std::string>> getBinaryPath(object::BuildIDRef);
+  Expected<std::optional<std::string>> getDebugBinaryPath(object::BuildIDRef);
+  Expected<std::optional<std::string>> getBinaryPath(object::BuildIDRef);
   // If the collection has not been updated since MinInterval, call update() and
   // return true. Otherwise return false. If update returns an error, return the
   // error.
diff --git a/llvm/include/llvm/Frontend/OpenMP/OMPIRBuilder.h b/llvm/include/llvm/Frontend/OpenMP/OMPIRBuilder.h
index 70fe88c..2c1abe9 100644
--- a/llvm/include/llvm/Frontend/OpenMP/OMPIRBuilder.h
+++ b/llvm/include/llvm/Frontend/OpenMP/OMPIRBuilder.h
@@ -94,7 +94,7 @@ public:
   std::optional<bool> HasRequiresUnifiedSharedMemory;
 
   // Flag for specifying if offloading is mandatory.
-  Optional<bool> OpenMPOffloadMandatory;
+  std::optional<bool> OpenMPOffloadMandatory;
 
   /// First separator used between the initial two parts of a name.
   std::optional<StringRef> FirstSeparator;
diff --git a/llvm/include/llvm/FuzzMutate/IRMutator.h b/llvm/include/llvm/FuzzMutate/IRMutator.h
index 9a1f7f0..d0708c7 100644
--- a/llvm/include/llvm/FuzzMutate/IRMutator.h
+++ b/llvm/include/llvm/FuzzMutate/IRMutator.h
@@ -77,8 +77,8 @@ public:
 class InjectorIRStrategy : public IRMutationStrategy {
   std::vector<fuzzerop::OpDescriptor> Operations;
 
-  Optional<fuzzerop::OpDescriptor> chooseOperation(Value *Src,
-                                                   RandomIRBuilder &IB);
+  std::optional<fuzzerop::OpDescriptor> chooseOperation(Value *Src,
+                                                        RandomIRBuilder &IB);
 
 public:
   InjectorIRStrategy(std::vector<fuzzerop::OpDescriptor> &&Operations)
diff --git a/llvm/include/llvm/LineEditor/LineEditor.h b/llvm/include/llvm/LineEditor/LineEditor.h
index 9f4ea5b..e8c7763 100644
--- a/llvm/include/llvm/LineEditor/LineEditor.h
+++ b/llvm/include/llvm/LineEditor/LineEditor.h
@@ -36,8 +36,8 @@ public:
 
   /// Reads a line.
   ///
-  /// \return The line, or llvm::Optional<std::string>() on EOF.
-  llvm::Optional<std::string> readLine() const;
+  /// \return The line, or std::optional<std::string>() on EOF.
+  std::optional<std::string> readLine() const;
 
   void saveHistory();
   void loadHistory();
diff --git a/llvm/include/llvm/Support/Error.h b/llvm/include/llvm/Support/Error.h
index 1305c9b..8a984db 100644
--- a/llvm/include/llvm/Support/Error.h
+++ b/llvm/include/llvm/Support/Error.h
@@ -1051,7 +1051,7 @@ inline void consumeError(Error Err) {
 /// Uses of this method are potentially indicative of problems: perhaps the
 /// error should be propagated further, or the error-producer should just
 /// return an Optional in the first place.
-template <typename T> Optional<T> expectedToOptional(Expected<T> &&E) {
+template <typename T> std::optional<T> expectedToOptional(Expected<T> &&E) {
   if (E)
     return std::move(*E);
   consumeError(E.takeError());
diff --git a/llvm/include/llvm/XRay/InstrumentationMap.h b/llvm/include/llvm/XRay/InstrumentationMap.h
index c95d406..211f328 100644
--- a/llvm/include/llvm/XRay/InstrumentationMap.h
+++ b/llvm/include/llvm/XRay/InstrumentationMap.h
@@ -90,10 +90,10 @@ public:
   const FunctionAddressMap &getFunctionAddresses() { return FunctionAddresses; }
 
   /// Returns an XRay computed function id, provided a function address.
-  Optional<int32_t> getFunctionId(uint64_t Addr) const;
+  std::optional<int32_t> getFunctionId(uint64_t Addr) const;
 
   /// Returns the function address for a function id.
-  Optional<uint64_t> getFunctionAddr(int32_t FuncId) const;
+  std::optional<uint64_t> getFunctionAddr(int32_t FuncId) const;
 
   /// Provide read-only access to the entries of the instrumentation map.
   const SledContainer &sleds() const { return Sleds; };
diff --git a/llvm/lib/CodeGen/BasicBlockSections.cpp b/llvm/lib/CodeGen/BasicBlockSections.cpp
index 776ab634..67db95b 100644
--- a/llvm/lib/CodeGen/BasicBlockSections.cpp
+++ b/llvm/lib/CodeGen/BasicBlockSections.cpp
@@ -167,7 +167,7 @@ static void updateBranches(
 bool getBBClusterInfoForFunction(
     const MachineFunction &MF,
     BasicBlockSectionsProfileReader *BBSectionsProfileReader,
-    std::vector<Optional<BBClusterInfo>> &V) {
+    std::vector<std::optional<BBClusterInfo>> &V) {
 
   // Find the assoicated cluster information.
   std::pair<bool, SmallVector<BBClusterInfo, 4>> P =
@@ -201,9 +201,9 @@ bool getBBClusterInfoForFunction(
 // and "Cold" succeeding all other clusters.
 // FuncBBClusterInfo represent the cluster information for basic blocks. If this
 // is empty, it means unique sections for all basic blocks in the function.
-static void
-assignSections(MachineFunction &MF,
-               const std::vector<Optional<BBClusterInfo>> &FuncBBClusterInfo) {
+static void assignSections(
+    MachineFunction &MF,
+    const std::vector<std::optional<BBClusterInfo>> &FuncBBClusterInfo) {
   assert(MF.hasBBSections() && "BB Sections is not set for function.");
   // This variable stores the section ID of the cluster containing eh_pads (if
   // all eh_pads are one cluster). If more than one cluster contain eh_pads, we
@@ -331,7 +331,7 @@ bool BasicBlockSections::runOnMachineFunction(MachineFunction &MF) {
 
   BBSectionsProfileReader = &getAnalysis<BasicBlockSectionsProfileReader>();
 
-  std::vector<Optional<BBClusterInfo>> FuncBBClusterInfo;
+  std::vector<std::optional<BBClusterInfo>> FuncBBClusterInfo;
   if (BBSectionsType == BasicBlockSection::List &&
       !getBBClusterInfoForFunction(MF, BBSectionsProfileReader,
                                    FuncBBClusterInfo))
diff --git a/llvm/lib/CodeGen/RegAllocGreedy.h b/llvm/lib/CodeGen/RegAllocGreedy.h
index 188cc56..e0ac88c 100644
--- a/llvm/lib/CodeGen/RegAllocGreedy.h
+++ b/llvm/lib/CodeGen/RegAllocGreedy.h
@@ -185,7 +185,7 @@ private:
   std::unique_ptr<Spiller> SpillerInstance;
   PQueue Queue;
   std::unique_ptr<VirtRegAuxInfo> VRAI;
-  Optional<ExtraRegInfo> ExtraInfo;
+  std::optional<ExtraRegInfo> ExtraInfo;
   std::unique_ptr<RegAllocEvictionAdvisor> EvictAdvisor;
 
   std::unique_ptr<RegAllocPriorityAdvisor> PriorityAdvisor;
diff --git a/llvm/lib/Debuginfod/Debuginfod.cpp b/llvm/lib/Debuginfod/Debuginfod.cpp
index 17d034d..026f118 100644
--- a/llvm/lib/Debuginfod/Debuginfod.cpp
+++ b/llvm/lib/Debuginfod/Debuginfod.cpp
@@ -425,7 +425,7 @@ Error DebuginfodCollection::findBinaries(StringRef Path) {
   return Error::success();
 }
 
-Expected<Optional<std::string>>
+Expected<std::optional<std::string>>
 DebuginfodCollection::getBinaryPath(BuildIDRef ID) {
   Log.push("getting binary path of ID " + buildIDToString(ID));
   std::shared_lock<sys::RWMutex> Guard(BinariesMutex);
@@ -437,7 +437,7 @@ DebuginfodCollection::getBinaryPath(BuildIDRef ID) {
   return std::nullopt;
 }
 
-Expected<Optional<std::string>>
+Expected<std::optional<std::string>>
 DebuginfodCollection::getDebugBinaryPath(BuildIDRef ID) {
   Log.push("getting debug binary path of ID " + buildIDToString(ID));
   std::shared_lock<sys::RWMutex> Guard(DebugBinariesMutex);
@@ -452,10 +452,10 @@ DebuginfodCollection::getDebugBinaryPath(BuildIDRef ID) {
 Expected<std::string> DebuginfodCollection::findBinaryPath(BuildIDRef ID) {
   {
     // Check collection; perform on-demand update if stale.
-    Expected<Optional<std::string>> PathOrErr = getBinaryPath(ID);
+    Expected<std::optional<std::string>> PathOrErr = getBinaryPath(ID);
     if (!PathOrErr)
       return PathOrErr.takeError();
-    Optional<std::string> Path = *PathOrErr;
+    std::optional<std::string> Path = *PathOrErr;
     if (!Path) {
       Expected<bool> UpdatedOrErr = updateIfStale();
       if (!UpdatedOrErr)
@@ -483,10 +483,10 @@ Expected<std::string> DebuginfodCollection::findBinaryPath(BuildIDRef ID) {
 
 Expected<std::string> DebuginfodCollection::findDebugBinaryPath(BuildIDRef ID) {
   // Check collection; perform on-demand update if stale.
-  Expected<Optional<std::string>> PathOrErr = getDebugBinaryPath(ID);
+  Expected<std::optional<std::string>> PathOrErr = getDebugBinaryPath(ID);
   if (!PathOrErr)
     return PathOrErr.takeError();
-  Optional<std::string> Path = *PathOrErr;
+  std::optional<std::string> Path = *PathOrErr;
   if (!Path) {
     Expected<bool> UpdatedOrErr = updateIfStale();
     if (!UpdatedOrErr)
diff --git a/llvm/lib/Frontend/OpenMP/OMPContext.cpp b/llvm/lib/Frontend/OpenMP/OMPContext.cpp
index 9217f8f..50ca01d 100644
--- a/llvm/lib/Frontend/OpenMP/OMPContext.cpp
+++ b/llvm/lib/Frontend/OpenMP/OMPContext.cpp
@@ -163,7 +163,7 @@ static int isVariantApplicableInContextHelper(
   // context based on the match kind selected by the user via
   // `implementation={extensions(match_[all,any,none])}'
   auto HandleTrait = [MK](TraitProperty Property,
-                          bool WasFound) -> Optional<bool> /* Result */ {
+                          bool WasFound) -> std::optional<bool> /* Result */ {
     // For kind "any" a single match is enough but we ignore non-matched
     // properties.
     if (MK == MK_ANY) {
@@ -212,7 +212,7 @@ static int isVariantApplicableInContextHelper(
         return Ctx.matchesISATrait(RawString);
       });
 
-    if (Optional<bool> Result = HandleTrait(Property, IsActiveTrait))
+    if (std::optional<bool> Result = HandleTrait(Property, IsActiveTrait))
       return *Result;
   }
 
@@ -232,7 +232,7 @@ static int isVariantApplicableInContextHelper(
       if (ConstructMatches)
         ConstructMatches->push_back(ConstructIdx - 1);
 
-      if (Optional<bool> Result = HandleTrait(Property, FoundInOrder))
+      if (std::optional<bool> Result = HandleTrait(Property, FoundInOrder))
         return *Result;
 
       if (!FoundInOrder) {
diff --git a/llvm/lib/FuzzMutate/IRMutator.cpp b/llvm/lib/FuzzMutate/IRMutator.cpp
index a588bc8..fa43422 100644
--- a/llvm/lib/FuzzMutate/IRMutator.cpp
+++ b/llvm/lib/FuzzMutate/IRMutator.cpp
@@ -102,7 +102,7 @@ std::vector<fuzzerop::OpDescriptor> InjectorIRStrategy::getDefaultOps() {
   return Ops;
 }
 
-Optional<fuzzerop::OpDescriptor>
+std::optional<fuzzerop::OpDescriptor>
 InjectorIRStrategy::chooseOperation(Value *Src, RandomIRBuilder &IB) {
   auto OpMatchesPred = [&Src](fuzzerop::OpDescriptor &Op) {
     return Op.SourcePreds[0].matches({}, Src);
diff --git a/llvm/lib/LineEditor/LineEditor.cpp b/llvm/lib/LineEditor/LineEditor.cpp
index 32a58f0..bb40841 100644
--- a/llvm/lib/LineEditor/LineEditor.cpp
+++ b/llvm/lib/LineEditor/LineEditor.cpp
@@ -248,7 +248,7 @@ void LineEditor::loadHistory() {
   }
 }
 
-Optional<std::string> LineEditor::readLine() const {
+std::optional<std::string> LineEditor::readLine() const {
   // Call el_gets to prompt the user and read the user's input.
   int LineLen = 0;
   const char *Line = ::el_gets(Data->EL, &LineLen);
@@ -292,7 +292,7 @@ LineEditor::~LineEditor() {
 void LineEditor::saveHistory() {}
 void LineEditor::loadHistory() {}
 
-Optional<std::string> LineEditor::readLine() const {
+std::optional<std::string> LineEditor::readLine() const {
   ::fprintf(Data->Out, "%s", Prompt.c_str());
 
   std::string Line;
diff --git a/llvm/lib/Support/VirtualFileSystem.cpp b/llvm/lib/Support/VirtualFileSystem.cpp
index fb6ce47..efb5faa8 100644
--- a/llvm/lib/Support/VirtualFileSystem.cpp
+++ b/llvm/lib/Support/VirtualFileSystem.cpp
@@ -1638,7 +1638,7 @@ class llvm::vfs::RedirectingFileSystemParser {
     return std::nullopt;
   }
 
-  Optional<RedirectingFileSystem::RootRelativeKind>
+  std::optional<RedirectingFileSystem::RootRelativeKind>
   parseRootRelativeKind(yaml::Node *N) {
     SmallString<12> Storage;
     StringRef Value;
diff --git a/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp b/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp
index d96aa2a..c8ef0d1 100644
--- a/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp
+++ b/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp
@@ -94,7 +94,7 @@ MachineTypes getDefaultMachine() {
   return getMachine(Triple(sys::getDefaultTargetTriple()));
 }
 
-Optional<std::string> getPrefix(StringRef Argv0) {
+std::optional<std::string> getPrefix(StringRef Argv0) {
   StringRef ProgName = llvm::sys::path::stem(Argv0);
   // x86_64-w64-mingw32-dlltool -> x86_64-w64-mingw32
   // llvm-dlltool -> None
@@ -149,7 +149,7 @@ int llvm::dlltoolDriverMain(llvm::ArrayRef<const char *> ArgsArr) {
   }
 
   COFF::MachineTypes Machine = getDefaultMachine();
-  if (Optional<std::string> Prefix = getPrefix(ArgsArr[0])) {
+  if (std::optional<std::string> Prefix = getPrefix(ArgsArr[0])) {
     Triple T(*Prefix);
     if (T.getArch() != Triple::UnknownArch)
       Machine = getMachine(T);
diff --git a/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
index 58a565d..c038875 100644
--- a/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
@@ -388,7 +388,7 @@ private:
   bool DetectUseAfterScope;
   bool UsePageAliases;
 
-  llvm::Optional<uint8_t> MatchAllTag;
+  std::optional<uint8_t> MatchAllTag;
 
   unsigned PointerTagShift;
   uint64_t TagMaskByte;
diff --git a/llvm/lib/XRay/InstrumentationMap.cpp b/llvm/lib/XRay/InstrumentationMap.cpp
index ce15a1d..ee190d9e 100644
--- a/llvm/lib/XRay/InstrumentationMap.cpp
+++ b/llvm/lib/XRay/InstrumentationMap.cpp
@@ -33,14 +33,15 @@
 using namespace llvm;
 using namespace xray;
 
-Optional<int32_t> InstrumentationMap::getFunctionId(uint64_t Addr) const {
+std::optional<int32_t> InstrumentationMap::getFunctionId(uint64_t Addr) const {
   auto I = FunctionIds.find(Addr);
   if (I != FunctionIds.end())
     return I->second;
   return std::nullopt;
 }
 
-Optional<uint64_t> InstrumentationMap::getFunctionAddr(int32_t FuncId) const {
+std::optional<uint64_t>
+InstrumentationMap::getFunctionAddr(int32_t FuncId) const {
   auto I = FunctionAddresses.find(FuncId);
   if (I != FunctionAddresses.end())
     return I->second;
diff --git a/llvm/unittests/ADT/STLForwardCompatTest.cpp b/llvm/unittests/ADT/STLForwardCompatTest.cpp
index a024012..e9cd88c 100644
--- a/llvm/unittests/ADT/STLForwardCompatTest.cpp
+++ b/llvm/unittests/ADT/STLForwardCompatTest.cpp
@@ -82,13 +82,15 @@ TEST(TransformTest, MoveTransformStd) {
 }
 
 TEST(TransformTest, TransformLlvm) {
-  llvm::Optional<int> A;
+  std::optional<int> A;
 
-  llvm::Optional<int> B = llvm::transformOptional(A, [&](int N) { return N + 1; });
+  std::optional<int> B =
+      llvm::transformOptional(A, [&](int N) { return N + 1; });
   EXPECT_FALSE(B.has_value());
 
   A = 3;
-  llvm::Optional<int> C = llvm::transformOptional(A, [&](int N) { return N + 1; });
+  std::optional<int> C =
+      llvm::transformOptional(A, [&](int N) { return N + 1; });
   EXPECT_TRUE(C.has_value());
   EXPECT_EQ(4, *C);
 }
@@ -96,10 +98,10 @@ TEST(TransformTest, TransformLlvm) {
 TEST(TransformTest, MoveTransformLlvm) {
   using llvm::MoveOnly;
 
-  llvm::Optional<MoveOnly> A;
+  std::optional<MoveOnly> A;
 
   MoveOnly::ResetCounts();
-  llvm::Optional<int> B = llvm::transformOptional(
+  std::optional<int> B = llvm::transformOptional(
       std::move(A), [&](const MoveOnly &M) { return M.val + 2; });
   EXPECT_FALSE(B.has_value());
   EXPECT_EQ(0u, MoveOnly::MoveConstructions);
@@ -108,7 +110,7 @@ TEST(TransformTest, MoveTransformLlvm) {
 
   A = MoveOnly(5);
   MoveOnly::ResetCounts();
-  llvm::Optional<int> C = llvm::transformOptional(
+  std::optional<int> C = llvm::transformOptional(
       std::move(A), [&](const MoveOnly &M) { return M.val + 2; });
   EXPECT_TRUE(C.has_value());
   EXPECT_EQ(7, *C);
diff --git a/llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp b/llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp
index d061381..ebfba7c 100644
--- a/llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp
+++ b/llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp
@@ -128,7 +128,7 @@ TEST(DWARFDebugFrame, DumpEH64FDE) {
 }
 
 static Error parseCFI(dwarf::CIE &C, ArrayRef<uint8_t> Instructions,
-                      Optional<uint64_t> Size = std::nullopt) {
+                      std::optional<uint64_t> Size = std::nullopt) {
   DWARFDataExtractor Data(Instructions, /*IsLittleEndian=*/true,
                           /*AddressSize=*/8);
   uint64_t Offset = 0;
diff --git a/llvm/unittests/DebugInfo/DWARF/DWARFExpressionCopyBytesTest.cpp b/llvm/unittests/DebugInfo/DWARF/DWARFExpressionCopyBytesTest.cpp
index d14b303..2129915 100644
--- a/llvm/unittests/DebugInfo/DWARF/DWARFExpressionCopyBytesTest.cpp
+++ b/llvm/unittests/DebugInfo/DWARF/DWARFExpressionCopyBytesTest.cpp
@@ -147,8 +147,8 @@ SmallString<0> DWARFExpressionCopyBytesTest::emitObjFile(StringRef ExprBytes) {
 
 void DWARFExpressionCopyBytesTest::parseCFIsAndCheckExpression(
     const llvm::object::ObjectFile &E, ArrayRef<uint8_t> Expected) {
-  auto FetchFirstCfaExpression =
-      [](const DWARFDebugFrame &EHFrame) -> Optional<CFIProgram::Instruction> {
+  auto FetchFirstCfaExpression = [](const DWARFDebugFrame &EHFrame)
+      -> std::optional<CFIProgram::Instruction> {
     for (const dwarf::FrameEntry &Entry : EHFrame.entries()) {
       const auto *CurFDE = dyn_cast<dwarf::FDE>(&Entry);
       if (!CurFDE)
diff --git a/llvm/unittests/DebugInfo/DWARF/DwarfGenerator.h b/llvm/unittests/DebugInfo/DWARF/DwarfGenerator.h
index e55dc07..4d97059b 100644
--- a/llvm/unittests/DebugInfo/DWARF/DwarfGenerator.h
+++ b/llvm/unittests/DebugInfo/DWARF/DwarfGenerator.h
@@ -220,7 +220,7 @@ private:
   // Calculate the number of bytes the Contents will take up.
   size_t getContentsSize() const;
 
-  llvm::Optional<DWARFDebugLine::Prologue> Prologue;
+  std::optional<DWARFDebugLine::Prologue> Prologue;
   std::vector<ValueAndLength> CustomPrologue;
   std::vector<ValueAndLength> Contents;
 
diff --git a/llvm/unittests/ExecutionEngine/Orc/CoreAPIsTest.cpp b/llvm/unittests/ExecutionEngine/Orc/CoreAPIsTest.cpp
index 3cd0504..d094bd3 100644
--- a/llvm/unittests/ExecutionEngine/Orc/CoreAPIsTest.cpp
+++ b/llvm/unittests/ExecutionEngine/Orc/CoreAPIsTest.cpp
@@ -99,7 +99,7 @@ TEST_F(CoreAPIsStandardTest, MaterializationSideEffctsOnlyBasic) {
   // results.
 
   std::unique_ptr<MaterializationResponsibility> FooR;
-  Optional<SymbolMap> Result;
+  std::optional<SymbolMap> Result;
 
   cantFail(JD.define(std::make_unique<SimpleMaterializationUnit>(
       SymbolFlagsMap(
diff --git a/llvm/unittests/IR/CFGBuilder.cpp b/llvm/unittests/IR/CFGBuilder.cpp
index fb05a9d..6a4e0874 100644
--- a/llvm/unittests/IR/CFGBuilder.cpp
+++ b/llvm/unittests/IR/CFGBuilder.cpp
@@ -126,13 +126,13 @@ void CFGBuilder::buildCFG(const std::vector<Arc> &NewArcs) {
   }
 }
 
-Optional<CFGBuilder::Update> CFGBuilder::getNextUpdate() const {
+std::optional<CFGBuilder::Update> CFGBuilder::getNextUpdate() const {
   if (UpdateIdx == Updates.size())
     return std::nullopt;
   return Updates[UpdateIdx];
 }
 
-Optional<CFGBuilder::Update> CFGBuilder::applyUpdate() {
+std::optional<CFGBuilder::Update> CFGBuilder::applyUpdate() {
   if (UpdateIdx == Updates.size())
     return std::nullopt;
   Update NextUpdate = Updates[UpdateIdx++];
diff --git a/llvm/unittests/IR/CFGBuilder.h b/llvm/unittests/IR/CFGBuilder.h
index 97be4a1..6fb03ee 100644
--- a/llvm/unittests/IR/CFGBuilder.h
+++ b/llvm/unittests/IR/CFGBuilder.h
@@ -72,8 +72,8 @@ public:
              std::vector<Update> Updates);
 
   BasicBlock *getOrAddBlock(StringRef BlockName);
-  Optional<Update> getNextUpdate() const;
-  Optional<Update> applyUpdate();
+  std::optional<Update> getNextUpdate() const;
+  std::optional<Update> applyUpdate();
   void dump(raw_ostream &OS = dbgs()) const;
 
 private:
diff --git a/llvm/unittests/IR/ConstantRangeTest.cpp b/llvm/unittests/IR/ConstantRangeTest.cpp
index 6d2d85c..cb53801 100644
--- a/llvm/unittests/IR/ConstantRangeTest.cpp
+++ b/llvm/unittests/IR/ConstantRangeTest.cpp
@@ -175,7 +175,7 @@ static void TestRange(const ConstantRange &CR, const SmallBitVector &Elems,
 }
 
 using UnaryRangeFn = llvm::function_ref<ConstantRange(const ConstantRange &)>;
-using UnaryIntFn = llvm::function_ref<Optional<APInt>(const APInt &)>;
+using UnaryIntFn = llvm::function_ref<std::optional<APInt>(const APInt &)>;
 
 static void TestUnaryOpExhaustive(UnaryRangeFn RangeFn, UnaryIntFn IntFn,
                                   PreferFn PreferenceFn = PreferSmallest) {
@@ -183,7 +183,7 @@ static void TestUnaryOpExhaustive(UnaryRangeFn RangeFn, UnaryIntFn IntFn,
   EnumerateConstantRanges(Bits, [&](const ConstantRange &CR) {
     SmallBitVector Elems(1 << Bits);
     ForeachNumInConstantRange(CR, [&](const APInt &N) {
-      if (Optional<APInt> ResultN = IntFn(N))
+      if (std::optional<APInt> ResultN = IntFn(N))
         Elems.set(ResultN->getZExtValue());
     });
     TestRange(RangeFn(CR), Elems, PreferenceFn, {CR});
@@ -192,8 +192,8 @@ static void TestUnaryOpExhaustive(UnaryRangeFn RangeFn, UnaryIntFn IntFn,
 
 using BinaryRangeFn = llvm::function_ref<ConstantRange(const ConstantRange &,
                                                        const ConstantRange &)>;
-using BinaryIntFn = llvm::function_ref<Optional<APInt>(const APInt &,
-                                                       const APInt &)>;
+using BinaryIntFn =
+    llvm::function_ref<std::optional<APInt>(const APInt &, const APInt &)>;
 using BinaryCheckFn = llvm::function_ref<bool(const ConstantRange &,
                                               const ConstantRange &)>;
 
@@ -233,7 +233,7 @@ static void TestBinaryOpExhaustive(BinaryRangeFn RangeFn, BinaryIntFn IntFn,
         SmallBitVector Elems(1 << Bits);
         ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
           ForeachNumInConstantRange(CR2, [&](const APInt &N2) {
-            if (Optional<APInt> ResultN = IntFn(N1, N2))
+            if (std::optional<APInt> ResultN = IntFn(N1, N2))
               Elems.set(ResultN->getZExtValue());
           });
         });
@@ -773,15 +773,14 @@ TEST_F(ConstantRangeTest, AddWithNoWrap) {
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.addWithNoWrap(CR2, OBO::NoSignedWrap);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         bool IsOverflow;
         APInt Res = N1.sadd_ov(N2, IsOverflow);
         if (IsOverflow)
           return std::nullopt;
         return Res;
       },
-      PreferSmallest,
-      CheckNonSignWrappedOnly);
+      PreferSmallest, CheckNonSignWrappedOnly);
 
   EXPECT_EQ(Empty.addWithNoWrap(Some, OBO::NoUnsignedWrap), Empty);
   EXPECT_EQ(Some.addWithNoWrap(Empty, OBO::NoUnsignedWrap), Empty);
@@ -827,15 +826,14 @@ TEST_F(ConstantRangeTest, AddWithNoWrap) {
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.addWithNoWrap(CR2, OBO::NoUnsignedWrap);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         bool IsOverflow;
         APInt Res = N1.uadd_ov(N2, IsOverflow);
         if (IsOverflow)
           return std::nullopt;
         return Res;
       },
-      PreferSmallest,
-      CheckNonWrappedOnly);
+      PreferSmallest, CheckNonWrappedOnly);
 
   EXPECT_EQ(ConstantRange(APInt(8, 50), APInt(8, 100))
                 .addWithNoWrap(ConstantRange(APInt(8, 20), APInt(8, 70)),
@@ -867,7 +865,7 @@ TEST_F(ConstantRangeTest, AddWithNoWrap) {
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.addWithNoWrap(CR2, OBO::NoUnsignedWrap | OBO::NoSignedWrap);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         bool IsOverflow1, IsOverflow2;
         APInt Res1 = N1.uadd_ov(N2, IsOverflow1);
         APInt Res2 = N1.sadd_ov(N2, IsOverflow2);
@@ -876,8 +874,7 @@ TEST_F(ConstantRangeTest, AddWithNoWrap) {
         assert(Res1 == Res2 && "Addition results differ?");
         return Res1;
       },
-      PreferSmallest,
-      CheckNonWrappedOrSignWrappedOnly);
+      PreferSmallest, CheckNonWrappedOrSignWrappedOnly);
 }
 
 TEST_F(ConstantRangeTest, Sub) {
@@ -916,33 +913,31 @@ TEST_F(ConstantRangeTest, SubWithNoWrap) {
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.subWithNoWrap(CR2, OBO::NoSignedWrap);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         bool IsOverflow;
         APInt Res = N1.ssub_ov(N2, IsOverflow);
         if (IsOverflow)
           return std::nullopt;
         return Res;
       },
-      PreferSmallest,
-      CheckNonSignWrappedOnly);
+      PreferSmallest, CheckNonSignWrappedOnly);
   TestBinaryOpExhaustive(
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.subWithNoWrap(CR2, OBO::NoUnsignedWrap);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         bool IsOverflow;
         APInt Res = N1.usub_ov(N2, IsOverflow);
         if (IsOverflow)
           return std::nullopt;
         return Res;
       },
-      PreferSmallest,
-      CheckNonWrappedOnly);
+      PreferSmallest, CheckNonWrappedOnly);
   TestBinaryOpExhaustive(
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.subWithNoWrap(CR2, OBO::NoUnsignedWrap | OBO::NoSignedWrap);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         bool IsOverflow1, IsOverflow2;
         APInt Res1 = N1.usub_ov(N2, IsOverflow1);
         APInt Res2 = N1.ssub_ov(N2, IsOverflow2);
@@ -951,8 +946,7 @@ TEST_F(ConstantRangeTest, SubWithNoWrap) {
         assert(Res1 == Res2 && "Subtraction results differ?");
         return Res1;
       },
-      PreferSmallest,
-      CheckNonWrappedOrSignWrappedOnly);
+      PreferSmallest, CheckNonWrappedOrSignWrappedOnly);
 }
 
 TEST_F(ConstantRangeTest, Multiply) {
@@ -1246,13 +1240,12 @@ TEST_F(ConstantRangeTest, URem) {
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.urem(CR2);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         if (N2.isZero())
           return std::nullopt;
         return N1.urem(N2);
       },
-      PreferSmallest,
-      CheckSingleElementsOnly);
+      PreferSmallest, CheckSingleElementsOnly);
 }
 
 TEST_F(ConstantRangeTest, SRem) {
@@ -1322,13 +1315,12 @@ TEST_F(ConstantRangeTest, SRem) {
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.srem(CR2);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         if (N2.isZero())
           return std::nullopt;
         return N1.srem(N2);
       },
-      PreferSmallest,
-      CheckSingleElementsOnly);
+      PreferSmallest, CheckSingleElementsOnly);
 }
 
 TEST_F(ConstantRangeTest, Shl) {
@@ -1360,7 +1352,7 @@ TEST_F(ConstantRangeTest, Shl) {
       [](const ConstantRange &CR1, const ConstantRange &CR2) {
         return CR1.shl(CR2);
       },
-      [](const APInt &N1, const APInt &N2) -> Optional<APInt> {
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
         if (N2.uge(N2.getBitWidth()))
           return std::nullopt;
         return N1.shl(N2);
@@ -2397,7 +2389,7 @@ TEST_F(ConstantRangeTest, Abs) {
 
   TestUnaryOpExhaustive(
       [](const ConstantRange &CR) { return CR.abs(/*IntMinIsPoison=*/true); },
-      [](const APInt &N) -> Optional<APInt> {
+      [](const APInt &N) -> std::optional<APInt> {
         if (N.isMinSignedValue())
           return std::nullopt;
         return N.abs();
diff --git a/llvm/unittests/IR/DominatorTreeTest.cpp b/llvm/unittests/IR/DominatorTreeTest.cpp
index 21f11c8..6260ce2 100644
--- a/llvm/unittests/IR/DominatorTreeTest.cpp
+++ b/llvm/unittests/IR/DominatorTreeTest.cpp
@@ -722,7 +722,7 @@ TEST(DominatorTree, InsertReachable) {
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());
 
-  Optional<CFGBuilder::Update> LastUpdate;
+  std::optional<CFGBuilder::Update> LastUpdate;
   while ((LastUpdate = B.applyUpdate())) {
     EXPECT_EQ(LastUpdate->Action, Insert);
     BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
@@ -748,7 +748,7 @@ TEST(DominatorTree, InsertReachable2) {
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());
 
-  Optional<CFGBuilder::Update> LastUpdate = B.applyUpdate();
+  std::optional<CFGBuilder::Update> LastUpdate = B.applyUpdate();
   EXPECT_TRUE(LastUpdate);
 
   EXPECT_EQ(LastUpdate->Action, Insert);
@@ -776,7 +776,7 @@ TEST(DominatorTree, InsertUnreachable) {
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());
 
-  Optional<CFGBuilder::Update> LastUpdate;
+  std::optional<CFGBuilder::Update> LastUpdate;
   while ((LastUpdate = B.applyUpdate())) {
     EXPECT_EQ(LastUpdate->Action, Insert);
     BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
@@ -797,7 +797,7 @@ TEST(DominatorTree, InsertFromUnreachable) {
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());
 
-  Optional<CFGBuilder::Update> LastUpdate = B.applyUpdate();
+  std::optional<CFGBuilder::Update> LastUpdate = B.applyUpdate();
   EXPECT_TRUE(LastUpdate);
 
   EXPECT_EQ(LastUpdate->Action, Insert);
@@ -827,7 +827,7 @@ TEST(DominatorTree, InsertMixed) {
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());
 
-  Optional<CFGBuilder::Update> LastUpdate;
+  std::optional<CFGBuilder::Update> LastUpdate;
   while ((LastUpdate = B.applyUpdate())) {
     EXPECT_EQ(LastUpdate->Action, Insert);
     BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
@@ -857,7 +857,7 @@ TEST(DominatorTree, InsertPermut) {
     PostDominatorTree PDT(*Holder.F);
     EXPECT_TRUE(PDT.verify());
 
-    Optional<CFGBuilder::Update> LastUpdate;
+    std::optional<CFGBuilder::Update> LastUpdate;
     while ((LastUpdate = B.applyUpdate())) {
       EXPECT_EQ(LastUpdate->Action, Insert);
       BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
@@ -884,7 +884,7 @@ TEST(DominatorTree, DeleteReachable) {
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());
 
-  Optional<CFGBuilder::Update> LastUpdate;
+  std::optional<CFGBuilder::Update> LastUpdate;
   while ((LastUpdate = B.applyUpdate())) {
     EXPECT_EQ(LastUpdate->Action, Delete);
     BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
@@ -910,7 +910,7 @@ TEST(DominatorTree, DeleteUnreachable) {
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());
 
-  Optional<CFGBuilder::Update> LastUpdate;
+  std::optional<CFGBuilder::Update> LastUpdate;
   while ((LastUpdate = B.applyUpdate())) {
     EXPECT_EQ(LastUpdate->Action, Delete);
     BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
@@ -940,7 +940,7 @@ TEST(DominatorTree, InsertDelete) {
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());
 
-  Optional<CFGBuilder::Update> LastUpdate;
+  std::optional<CFGBuilder::Update> LastUpdate;
   while ((LastUpdate = B.applyUpdate())) {
     BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
     BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
@@ -978,7 +978,7 @@ TEST(DominatorTree, InsertDeleteExhaustive) {
     PostDominatorTree PDT(*Holder.F);
     EXPECT_TRUE(PDT.verify());
 
-    Optional<CFGBuilder::Update> LastUpdate;
+    std::optional<CFGBuilder::Update> LastUpdate;
     while ((LastUpdate = B.applyUpdate())) {
       BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
       BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
diff --git a/llvm/unittests/IR/VPIntrinsicTest.cpp b/llvm/unittests/IR/VPIntrinsicTest.cpp
index 6ef9ccc..5abead9 100644
--- a/llvm/unittests/IR/VPIntrinsicTest.cpp
+++ b/llvm/unittests/IR/VPIntrinsicTest.cpp
@@ -163,7 +163,7 @@ protected:
 
 /// Check that the property scopes include/llvm/IR/VPIntrinsics.def are closed.
 TEST_F(VPIntrinsicTest, VPIntrinsicsDefScopes) {
-  Optional<Intrinsic::ID> ScopeVPID;
+  std::optional<Intrinsic::ID> ScopeVPID;
 #define BEGIN_REGISTER_VP_INTRINSIC(VPID, ...)                                 \
   ASSERT_FALSE(ScopeVPID.has_value());                                         \
   ScopeVPID = Intrinsic::VPID;
@@ -172,7 +172,7 @@ TEST_F(VPIntrinsicTest, VPIntrinsicsDefScopes) {
   ASSERT_EQ(*ScopeVPID, Intrinsic::VPID);                                      \
   ScopeVPID = std::nullopt;
 
-  Optional<ISD::NodeType> ScopeOPC;
+  std::optional<ISD::NodeType> ScopeOPC;
 #define BEGIN_REGISTER_VP_SDNODE(SDOPC, ...)                                   \
   ASSERT_FALSE(ScopeOPC.has_value());                                          \
   ScopeOPC = ISD::SDOPC;
diff --git a/llvm/unittests/Remarks/YAMLRemarksSerializerTest.cpp b/llvm/unittests/Remarks/YAMLRemarksSerializerTest.cpp
index 6ad665b..fef1a93 100644
--- a/llvm/unittests/Remarks/YAMLRemarksSerializerTest.cpp
+++ b/llvm/unittests/Remarks/YAMLRemarksSerializerTest.cpp
@@ -24,8 +24,8 @@ using namespace llvm;
 
 static void check(remarks::Format SerializerFormat,
                   remarks::SerializerMode Mode, ArrayRef<remarks::Remark> Rs,
-                  StringRef ExpectedR, Optional<StringRef> ExpectedMeta,
-                  Optional<remarks::StringTable> StrTab = std::nullopt) {
+                  StringRef ExpectedR, std::optional<StringRef> ExpectedMeta,
+                  std::optional<remarks::StringTable> StrTab = std::nullopt) {
   std::string Buf;
   raw_string_ostream OS(Buf);
   Expected<std::unique_ptr<remarks::RemarkSerializer>> MaybeS = [&] {
@@ -53,7 +53,7 @@ static void check(remarks::Format SerializerFormat,
 
 static void check(remarks::Format SerializerFormat, const remarks::Remark &R,
                   StringRef ExpectedR, StringRef ExpectedMeta,
-                  Optional<remarks::StringTable> StrTab = std::nullopt) {
+                  std::optional<remarks::StringTable> StrTab = std::nullopt) {
   return check(SerializerFormat, remarks::SerializerMode::Separate,
                makeArrayRef(&R, &R + 1), ExpectedR, ExpectedMeta,
                std::move(StrTab));
@@ -62,7 +62,7 @@ static void check(remarks::Format SerializerFormat, const remarks::Remark &R,
 static void
 checkStandalone(remarks::Format SerializerFormat, const remarks::Remark &R,
                 StringRef ExpectedR,
-                Optional<remarks::StringTable> StrTab = std::nullopt) {
+                std::optional<remarks::StringTable> StrTab = std::nullopt) {
   return check(SerializerFormat, remarks::SerializerMode::Standalone,
                makeArrayRef(&R, &R + 1), ExpectedR,
                /*ExpectedMeta=*/std::nullopt, std::move(StrTab));
diff --git a/llvm/unittests/Support/TypeTraitsTest.cpp b/llvm/unittests/Support/TypeTraitsTest.cpp
index 845c38d..85f985d 100644
--- a/llvm/unittests/Support/TypeTraitsTest.cpp
+++ b/llvm/unittests/Support/TypeTraitsTest.cpp
@@ -120,7 +120,7 @@ TEST(Triviality, ADT) {
   TrivialityTester<llvm::PointerIntPair<int *, 2>, true, true>();
 #if defined(_LIBCPP_VERSION) ||                                                \
     (defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE >= 8)
-  TrivialityTester<llvm::Optional<int>, true, true>();
+  TrivialityTester<std::optional<int>, true, true>();
 #endif
 }
 
diff --git a/llvm/unittests/Testing/Support/TempPathTest.cpp b/llvm/unittests/Testing/Support/TempPathTest.cpp
index 11820b0..37186f5 100644
--- a/llvm/unittests/Testing/Support/TempPathTest.cpp
+++ b/llvm/unittests/Testing/Support/TempPathTest.cpp
@@ -19,7 +19,7 @@ using llvm::unittest::TempLink;
 namespace {
 
 TEST(TempPathTest, TempDir) {
-  Optional<TempDir> Dir1, Dir2;
+  std::optional<TempDir> Dir1, Dir2;
   StringRef Prefix = "temp-path-test";
   Dir1.emplace(Prefix, /*Unique=*/true);
   EXPECT_EQ(Prefix,
@@ -44,7 +44,7 @@ TEST(TempPathTest, TempFile) {
   TempDir D("temp-path-test", /*Unique=*/true);
   ASSERT_TRUE(sys::fs::exists(D.path()));
 
-  Optional<TempFile> File1, File2;
+  std::optional<TempFile> File1, File2;
   File1.emplace(D.path("file"), "suffix", "content");
   EXPECT_EQ("file.suffix", sys::path::filename(File1->path()));
   {
@@ -73,7 +73,7 @@ TEST(TempPathTest, TempLink) {
   ASSERT_TRUE(sys::fs::exists(D.path()));
   TempFile File(D.path("file"), "suffix", "content");
 
-  Optional<TempLink> Link1, Link2;
+  std::optional<TempLink> Link1, Link2;
   Link1.emplace(File.path(), D.path("link"));
   EXPECT_EQ("link", sys::path::filename(Link1->path()));
   {
diff --git a/llvm/utils/UnicodeData/UnicodeNameMappingGenerator.cpp b/llvm/utils/UnicodeData/UnicodeNameMappingGenerator.cpp
index d74f81e..b19e034 100644
--- a/llvm/utils/UnicodeData/UnicodeNameMappingGenerator.cpp
+++ b/llvm/utils/UnicodeData/UnicodeNameMappingGenerator.cpp
@@ -327,7 +327,7 @@ private:
     std::vector<std::unique_ptr<Node>> Children;
     std::string Name;
     Node *Parent = nullptr;
-    llvm::Optional<char32_t> Value;
+    std::optional<char32_t> Value;
   };
 
   std::unique_ptr<Node> Root = std::make_unique<Node>("");