diff --git a/bolt/include/bolt/Core/DebugData.h b/bolt/include/bolt/Core/DebugData.h
index 5be678cc12e2..1ba31fe4d223 100644
--- a/bolt/include/bolt/Core/DebugData.h
+++ b/bolt/include/bolt/Core/DebugData.h
@@ -424,7 +424,7 @@ public:
 
   /// Initializes Buffer and Stream.
   void initialize(const DWARFSection &StrOffsetsSection,
-                  const Optional<StrOffsetsContributionDescriptor> Contr);
+                  const std::optional<StrOffsetsContributionDescriptor> Contr);
 
   /// Update Str offset in .debug_str in .debug_str_offsets.
   void updateAddressMap(uint32_t Index, uint32_t Address);
diff --git a/bolt/lib/Core/BinaryContext.cpp b/bolt/lib/Core/BinaryContext.cpp
index 8f2bc4ceecc4..208b106c68f2 100644
--- a/bolt/lib/Core/BinaryContext.cpp
+++ b/bolt/lib/Core/BinaryContext.cpp
@@ -1482,14 +1482,14 @@ unsigned BinaryContext::addDebugFilenameToUnit(const uint32_t DestCUID,
          "FileIndex out of range for the compilation unit.");
   StringRef Dir = "";
   if (FileNames[FileIndex - 1].DirIdx != 0) {
-    if (Optional<const char *> DirName = dwarf::toString(
+    if (std::optional<const char *> DirName = dwarf::toString(
             LineTable->Prologue
                 .IncludeDirectories[FileNames[FileIndex - 1].DirIdx - 1])) {
       Dir = *DirName;
     }
   }
   StringRef FileName = "";
-  if (Optional<const char *> FName =
+  if (std::optional<const char *> FName =
           dwarf::toString(FileNames[FileIndex - 1].Name))
     FileName = *FName;
   assert(FileName != "");
@@ -1545,7 +1545,7 @@ DWARFContext *BinaryContext::getDWOContext() const {
 void BinaryContext::preprocessDWODebugInfo() {
   for (const std::unique_ptr<DWARFUnit> &CU : DwCtx->compile_units()) {
     DWARFUnit *const DwarfUnit = CU.get();
-    if (llvm::Optional<uint64_t> DWOId = DwarfUnit->getDWOId()) {
+    if (std::optional<uint64_t> DWOId = DwarfUnit->getDWOId()) {
       DWARFUnit *DWOCU = DwarfUnit->getNonSkeletonUnitDIE(false).getDwarfUnit();
       if (!DWOCU->isDWOUnit()) {
         std::string DWOName = dwarf::toString(
@@ -1648,9 +1648,9 @@ void BinaryContext::preprocessDebugInfo() {
       std::optional<MD5::MD5Result> Checksum;
       if (LineTable->Prologue.ContentTypes.HasMD5)
         Checksum = LineTable->Prologue.FileNames[0].Checksum;
-      Optional<const char *> Name =
+      std::optional<const char *> Name =
           dwarf::toString(CU->getUnitDIE().find(dwarf::DW_AT_name), nullptr);
-      if (Optional<uint64_t> DWOID = CU->getDWOId()) {
+      if (std::optional<uint64_t> DWOID = CU->getDWOId()) {
         auto Iter = DWOCUs.find(*DWOID);
         assert(Iter != DWOCUs.end() && "DWO CU was not found.");
         Name = dwarf::toString(
@@ -1675,12 +1675,13 @@ void BinaryContext::preprocessDebugInfo() {
       // means empty dir.
       StringRef Dir = "";
       if (FileNames[I].DirIdx != 0 || DwarfVersion >= 5)
-        if (Optional<const char *> DirName = dwarf::toString(
+        if (std::optional<const char *> DirName = dwarf::toString(
                 LineTable->Prologue
                     .IncludeDirectories[FileNames[I].DirIdx - Offset]))
           Dir = *DirName;
       StringRef FileName = "";
-      if (Optional<const char *> FName = dwarf::toString(FileNames[I].Name))
+      if (std::optional<const char *> FName =
+              dwarf::toString(FileNames[I].Name))
         FileName = *FName;
       assert(FileName != "");
       std::optional<MD5::MD5Result> Checksum;
@@ -1811,7 +1812,7 @@ static void printDebugInfo(raw_ostream &OS, const MCInst &Instruction,
 
   const DWARFDebugLine::Row &Row = LineTable->Rows[RowRef.RowIndex - 1];
   StringRef FileName = "";
-  if (Optional<const char *> FName =
+  if (std::optional<const char *> FName =
           dwarf::toString(LineTable->Prologue.FileNames[Row.File - 1].Name))
     FileName = *FName;
   OS << " # debug line " << FileName << ":" << Row.Line;
diff --git a/bolt/lib/Core/DebugData.cpp b/bolt/lib/Core/DebugData.cpp
index 6d39353dcf72..d0e8988405f6 100644
--- a/bolt/lib/Core/DebugData.cpp
+++ b/bolt/lib/Core/DebugData.cpp
@@ -49,7 +49,7 @@ findAttributeInfo(const DWARFDie DIE,
   const DWARFUnit &U = *DIE.getDwarfUnit();
   uint64_t Offset =
       AbbrevDecl->getAttributeOffsetFromIndex(Index, DIE.getOffset(), U);
-  Optional<DWARFFormValue> Value =
+  std::optional<DWARFFormValue> Value =
       AbbrevDecl->getAttributeValueFromOffset(Index, Offset, U);
   if (!Value)
     return std::nullopt;
@@ -57,7 +57,7 @@ findAttributeInfo(const DWARFDie DIE,
   const DWARFAbbreviationDeclaration::AttributeSpec *AttrVal =
       AbbrevDecl->attributes().begin() + Index;
   uint32_t ValSize = 0;
-  Optional<int64_t> ValSizeOpt = AttrVal->getByteSize(U);
+  std::optional<int64_t> ValSizeOpt = AttrVal->getByteSize(U);
   if (ValSizeOpt) {
     ValSize = static_cast<uint32_t>(*ValSizeOpt);
   } else {
@@ -81,7 +81,7 @@ Optional<AttrInfo> findAttributeInfo(const DWARFDie DIE,
       DIE.getAbbreviationDeclarationPtr();
   if (!AbbrevDecl)
     return std::nullopt;
-  Optional<uint32_t> Index = AbbrevDecl->findAttributeIndex(Attr);
+  std::optional<uint32_t> Index = AbbrevDecl->findAttributeIndex(Attr);
   if (!Index)
     return std::nullopt;
   return findAttributeInfo(DIE, AbbrevDecl, *Index);
@@ -421,7 +421,7 @@ AddressSectionBuffer DebugAddrWriterDwarf5::finalize() {
     // for it.
     if (AMIter == AddressMaps.end()) {
       AMIter = AddressMaps.insert({CUID, AddressForDWOCU()}).first;
-      Optional<uint64_t> BaseOffset = CU->getAddrOffsetSectionBase();
+      std::optional<uint64_t> BaseOffset = CU->getAddrOffsetSectionBase();
       if (!BaseOffset)
         continue;
       // Address base offset is to the first entry.
@@ -1067,7 +1067,7 @@ std::string DebugInfoBinaryPatcher::patchBinary(StringRef BinaryContents) {
 
 void DebugStrOffsetsWriter::initialize(
     const DWARFSection &StrOffsetsSection,
-    const Optional<StrOffsetsContributionDescriptor> Contr) {
+    const std::optional<StrOffsetsContributionDescriptor> Contr) {
   if (!Contr)
     return;
 
diff --git a/bolt/lib/Core/Exceptions.cpp b/bolt/lib/Core/Exceptions.cpp
index 6ec6d05c7a6c..b1976ed7669b 100644
--- a/bolt/lib/Core/Exceptions.cpp
+++ b/bolt/lib/Core/Exceptions.cpp
@@ -115,7 +115,7 @@ void BinaryFunction::parseLSDA(ArrayRef<uint8_t> LSDASectionData,
   uint8_t LPStartEncoding = Data.getU8(&Offset);
   uint64_t LPStart = 0;
   // Convert to offset if LPStartEncoding is typed absptr DW_EH_PE_absptr
-  if (Optional<uint64_t> MaybeLPStart = Data.getEncodedPointer(
+  if (std::optional<uint64_t> MaybeLPStart = Data.getEncodedPointer(
           &Offset, LPStartEncoding, Offset + LSDASectionAddress))
     LPStart = (LPStartEncoding && 0xFF == 0) ? *MaybeLPStart
                                              : *MaybeLPStart - Address;
@@ -496,7 +496,7 @@ bool CFIReaderWriter::fillCFIInfoFor(BinaryFunction &Function) const {
     return true;
 
   const FDE &CurFDE = *I->second;
-  Optional<uint64_t> LSDA = CurFDE.getLSDAAddress();
+  std::optional<uint64_t> LSDA = CurFDE.getLSDAAddress();
   Function.setLSDAAddress(LSDA ? *LSDA : 0);
 
   uint64_t Offset = Function.getFirstInstructionOffset();
@@ -785,7 +785,7 @@ Error EHFrameParser::parseCIE(uint64_t StartOffset) {
       break;
     case 'P': {
       uint32_t PersonalityEncoding = Data.getU8(&Offset);
-      Optional<uint64_t> Personality =
+      std::optional<uint64_t> Personality =
           Data.getEncodedPointer(&Offset, PersonalityEncoding,
                                  EHFrameAddress ? EHFrameAddress + Offset : 0);
       // Patch personality address
@@ -817,7 +817,7 @@ Error EHFrameParser::parseCIE(uint64_t StartOffset) {
 
 Error EHFrameParser::parseFDE(uint64_t CIEPointer,
                               uint64_t StartStructureOffset) {
-  Optional<uint64_t> LSDAAddress;
+  std::optional<uint64_t> LSDAAddress;
   CIEInfo *Cie = CIEs[StartStructureOffset - CIEPointer];
 
   // The address size is encoded in the CIE we reference.
diff --git a/bolt/lib/Rewrite/DWARFRewriter.cpp b/bolt/lib/Rewrite/DWARFRewriter.cpp
index abcb373f4b65..72eac7b2f777 100644
--- a/bolt/lib/Rewrite/DWARFRewriter.cpp
+++ b/bolt/lib/Rewrite/DWARFRewriter.cpp
@@ -121,7 +121,7 @@ static std::string
 getDWOName(llvm::DWARFUnit &CU,
            std::unordered_map<std::string, uint32_t> *NameToIndexMap,
            std::unordered_map<uint64_t, std::string> &DWOIdToName) {
-  llvm::Optional<uint64_t> DWOId = CU.getDWOId();
+  std::optional<uint64_t> DWOId = CU.getDWOId();
   assert(DWOId && "DWO ID not found.");
   (void)DWOId;
   auto NameIter = DWOIdToName.find(*DWOId);
@@ -198,7 +198,7 @@ void DWARFRewriter::updateDebugInfo() {
       LocListWritersByCU[CUIndex] =
           std::make_unique<DebugLoclistWriter>(*CU.get(), DwarfVersion, false);
 
-      if (Optional<uint64_t> DWOId = CU->getDWOId()) {
+      if (std::optional<uint64_t> DWOId = CU->getDWOId()) {
         assert(LocListWritersByCU.count(*DWOId) == 0 &&
                "RangeLists writer for DWO unit already exists.");
         auto RangeListsSectionWriter =
@@ -211,7 +211,7 @@ void DWARFRewriter::updateDebugInfo() {
       LocListWritersByCU[CUIndex] = std::make_unique<DebugLocWriter>();
     }
 
-    if (Optional<uint64_t> DWOId = CU->getDWOId()) {
+    if (std::optional<uint64_t> DWOId = CU->getDWOId()) {
       assert(LocListWritersByCU.count(*DWOId) == 0 &&
              "LocList writer for DWO unit already exists.");
       // Work around some bug in llvm-15. If I pass in directly lld reports
@@ -258,7 +258,7 @@ void DWARFRewriter::updateDebugInfo() {
     // its matching split/DWO CU.
     Optional<DWARFUnit *> SplitCU;
     Optional<uint64_t> RangesBase;
-    llvm::Optional<uint64_t> DWOId = Unit->getDWOId();
+    std::optional<uint64_t> DWOId = Unit->getDWOId();
     StrOffstsWriter->initialize(Unit->getStringOffsetSection(),
                                 Unit->getStringOffsetsTableContribution());
     if (DWOId)
@@ -495,7 +495,7 @@ void DWARFRewriter::updateUnitDebugInfo(
     }
     case dwarf::DW_TAG_call_site: {
       auto patchPC = [&](AttrInfo &AttrVal, StringRef Entry) -> void {
-        Optional<uint64_t> Address = AttrVal.V.getAsAddress();
+        std::optional<uint64_t> Address = AttrVal.V.getAsAddress();
         const BinaryFunction *Function =
             BC.getBinaryFunctionContainingAddress(*Address);
         uint64_t UpdatedAddress = *Address;
@@ -539,7 +539,7 @@ void DWARFRewriter::updateUnitDebugInfo(
                                 : Value.getAsSectionOffset().value();
           DebugLocationsVector InputLL;
 
-          Optional<object::SectionedAddress> SectionAddress =
+          std::optional<object::SectionedAddress> SectionAddress =
               Unit.getBaseAddress();
           uint64_t BaseAddress = 0;
           if (SectionAddress)
@@ -547,7 +547,7 @@ void DWARFRewriter::updateUnitDebugInfo(
 
           if (Unit.getVersion() >= 5 &&
               AttrVal->V.getForm() == dwarf::DW_FORM_loclistx) {
-            Optional<uint64_t> LocOffset = Unit.getLoclistOffset(Offset);
+            std::optional<uint64_t> LocOffset = Unit.getLoclistOffset(Offset);
             assert(LocOffset && "Location Offset is invalid.");
             Offset = *LocOffset;
           }
@@ -579,14 +579,14 @@ void DWARFRewriter::updateUnitDebugInfo(
                       Entry.Value0, Entry.Value0 + Entry.Value1, Entry.Loc});
                   break;
                 case dwarf::DW_LLE_base_addressx: {
-                  Optional<object::SectionedAddress> EntryAddress =
+                  std::optional<object::SectionedAddress> EntryAddress =
                       Unit.getAddrOffsetSectionItem(Entry.Value0);
                   assert(EntryAddress && "base Address not found.");
                   BaseAddress = EntryAddress->Address;
                   break;
                 }
                 case dwarf::DW_LLE_startx_length: {
-                  Optional<object::SectionedAddress> EntryAddress =
+                  std::optional<object::SectionedAddress> EntryAddress =
                       Unit.getAddrOffsetSectionItem(Entry.Value0);
                   assert(EntryAddress && "Address does not exist.");
                   InputLL.emplace_back(DebugLocationEntry{
@@ -595,10 +595,10 @@ void DWARFRewriter::updateUnitDebugInfo(
                   break;
                 }
                 case dwarf::DW_LLE_startx_endx: {
-                  Optional<object::SectionedAddress> StartAddress =
+                  std::optional<object::SectionedAddress> StartAddress =
                       Unit.getAddrOffsetSectionItem(Entry.Value0);
                   assert(StartAddress && "Start Address does not exist.");
-                  Optional<object::SectionedAddress> EndAddress =
+                  std::optional<object::SectionedAddress> EndAddress =
                       Unit.getAddrOffsetSectionItem(Entry.Value1);
                   assert(EndAddress && "Start Address does not exist.");
                   InputLL.emplace_back(DebugLocationEntry{
@@ -661,7 +661,7 @@ void DWARFRewriter::updateUnitDebugInfo(
                     Expr.getCode() == dwarf::DW_OP_addrx))
                 continue;
               const uint64_t Index = Expr.getRawOperand(0);
-              Optional<object::SectionedAddress> EntryAddress =
+              std::optional<object::SectionedAddress> EntryAddress =
                   Unit.getAddrOffsetSectionItem(Index);
               assert(EntryAddress && "Address is not found.");
               assert(Index <= std::numeric_limits<uint32_t>::max() &&
@@ -694,7 +694,7 @@ void DWARFRewriter::updateUnitDebugInfo(
                      findAttributeInfo(DIE, dwarf::DW_AT_low_pc)) {
         AttrOffset = AttrVal->Offset;
         Value = AttrVal->V;
-        const Optional<uint64_t> Result = Value.getAsAddress();
+        const std::optional<uint64_t> Result = Value.getAsAddress();
         if (Result) {
           const uint64_t Address = *Result;
           uint64_t NewAddress = 0;
@@ -742,7 +742,8 @@ void DWARFRewriter::updateUnitDebugInfo(
           continue;
         // If input is DWP file we need to keep track of which TU came from each
         // CU, so we can write it out correctly.
-        if (Optional<uint64_t> Val = SignatureAttrVal->V.getAsReferenceUVal())
+        if (std::optional<uint64_t> Val =
+                SignatureAttrVal->V.getAsReferenceUVal())
           TypeSignaturesPerCU[*DIE.getDwarfUnit()->getDWOId()].insert(*Val);
         else {
           errs() << "BOT-ERROR: DW_AT_signature form is not supported.\n";
@@ -919,9 +920,9 @@ void DWARFRewriter::updateLineTableOffsets(const MCAsmLayout &Layout) {
   std::unordered_map<uint64_t, uint64_t> DebugLineOffsetMap;
 
   auto GetStatementListValue = [](DWARFUnit *Unit) {
-    Optional<DWARFFormValue> StmtList =
+    std::optional<DWARFFormValue> StmtList =
         Unit->getUnitDIE().find(dwarf::DW_AT_stmt_list);
-    Optional<uint64_t> Offset = dwarf::toSectionOffset(StmtList);
+    std::optional<uint64_t> Offset = dwarf::toSectionOffset(StmtList);
     assert(Offset && "Was not able to retreive value of DW_AT_stmt_list.");
     return *Offset;
   };
@@ -1412,7 +1413,7 @@ void DWARFRewriter::writeDWP(
   }
 
   for (const std::unique_ptr<DWARFUnit> &CU : BC.DwCtx->compile_units()) {
-    Optional<uint64_t> DWOId = CU->getDWOId();
+    std::optional<uint64_t> DWOId = CU->getDWOId();
     if (!DWOId)
       continue;
 
@@ -1581,7 +1582,7 @@ void DWARFRewriter::writeDWOFiles(
   }
 
   for (const std::unique_ptr<DWARFUnit> &CU : BC.DwCtx->compile_units()) {
-    Optional<uint64_t> DWOId = CU->getDWOId();
+    std::optional<uint64_t> DWOId = CU->getDWOId();
     if (!DWOId)
       continue;
 
diff --git a/lld/COFF/DebugTypes.cpp b/lld/COFF/DebugTypes.cpp
index af463c218bb9..d723e48e99bc 100644
--- a/lld/COFF/DebugTypes.cpp
+++ b/lld/COFF/DebugTypes.cpp
@@ -315,7 +315,7 @@ Error TpiSource::mergeDebugT(TypeMerger *m) {
   // When dealing with PCH.OBJ, some indices were already merged.
   unsigned nbHeadIndices = indexMapStorage.size();
 
-  Optional<PCHMergerInfo> pchInfo;
+  std::optional<PCHMergerInfo> pchInfo;
   if (auto err = mergeTypeAndIdRecords(m->idTable, m->typeTable,
                                        indexMapStorage, types, pchInfo))
     fatal("codeview::mergeTypeAndIdRecords failed: " +
diff --git a/lld/ELF/DWARF.cpp b/lld/ELF/DWARF.cpp
index be4609fa229b..a56454c53a6d 100644
--- a/lld/ELF/DWARF.cpp
+++ b/lld/ELF/DWARF.cpp
@@ -127,7 +127,7 @@ LLDDwarfObj<ELFT>::findAux(const InputSectionBase &sec, uint64_t pos,
   DataRefImpl d;
   d.p = getAddend<ELFT>(rel);
   return RelocAddrEntry{secIndex, RelocationRef(d, nullptr),
-                        val,      Optional<object::RelocationRef>(),
+                        val,      std::optional<object::RelocationRef>(),
                         0,        LLDRelocationResolver<RelTy>::resolve};
 }
 
diff --git a/lldb/source/Expression/DWARFExpression.cpp b/lldb/source/Expression/DWARFExpression.cpp
index e92216bb5e4d..d6029aa13709 100644
--- a/lldb/source/Expression/DWARFExpression.cpp
+++ b/lldb/source/Expression/DWARFExpression.cpp
@@ -2613,10 +2613,10 @@ bool DWARFExpression::ParseDWARFLocationList(
       dwarf_cu->GetLocationTable(data);
   Log *log = GetLog(LLDBLog::Expressions);
   auto lookup_addr =
-      [&](uint32_t index) -> llvm::Optional<llvm::object::SectionedAddress> {
+      [&](uint32_t index) -> std::optional<llvm::object::SectionedAddress> {
     addr_t address = dwarf_cu->ReadAddressFromDebugAddrSection(index);
     if (address == LLDB_INVALID_ADDRESS)
-      return llvm::None;
+      return std::nullopt;
     return llvm::object::SectionedAddress{address};
   };
   auto process_list = [&](llvm::Expected<llvm::DWARFLocationExpression> loc) {
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
index 21ef765d1bba..399578b6a353 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
@@ -578,7 +578,7 @@ llvm::Expected<uint64_t> DWARFUnit::GetRnglistOffset(uint32_t Index) {
                                    "DW_FORM_rnglistx cannot be used without "
                                    "DW_AT_rnglists_base for CU at 0x%8.8x",
                                    GetOffset());
-  if (llvm::Optional<uint64_t> off = GetRnglistTable()->getOffsetEntry(
+  if (std::optional<uint64_t> off = GetRnglistTable()->getOffsetEntry(
           GetRnglistData().GetAsLLVM(), Index))
     return *off + m_ranges_base;
   return llvm::createStringError(
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h
index 26e322059743..9fdab3c5273f 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h
@@ -243,7 +243,7 @@ public:
     if (!m_loclist_table_header)
       return llvm::None;
 
-    llvm::Optional<uint64_t> Offset = m_loclist_table_header->getOffsetEntry(
+    std::optional<uint64_t> Offset = m_loclist_table_header->getOffsetEntry(
         m_dwarf.GetDWARFContext().getOrLoadLocListsData().GetAsLLVM(), Index);
     if (!Offset)
       return llvm::None;
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DebugNamesDWARFIndex.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DebugNamesDWARFIndex.cpp
index a8e9b41c83fe..d0b2ef66d401 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DebugNamesDWARFIndex.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DebugNamesDWARFIndex.cpp
@@ -43,7 +43,7 @@ DebugNamesDWARFIndex::GetUnits(const DebugNames &debug_names) {
 
 llvm::Optional<DIERef>
 DebugNamesDWARFIndex::ToDIERef(const DebugNames::Entry &entry) {
-  llvm::Optional<uint64_t> cu_offset = entry.getCUOffset();
+  std::optional<uint64_t> cu_offset = entry.getCUOffset();
   if (!cu_offset)
     return llvm::None;
 
@@ -52,7 +52,7 @@ DebugNamesDWARFIndex::ToDIERef(const DebugNames::Entry &entry) {
     return llvm::None;
 
   cu = &cu->GetNonSkeletonUnit();
-  if (llvm::Optional<uint64_t> die_offset = entry.getDIEUnitOffset())
+  if (std::optional<uint64_t> die_offset = entry.getDIEUnitOffset())
     return DIERef(cu->GetSymbolFileDWARF().GetDwoNum(),
                   DIERef::Section::DebugInfo, cu->GetOffset() + *die_offset);
 
diff --git a/lldb/source/Plugins/SymbolFile/NativePDB/CompileUnitIndex.cpp b/lldb/source/Plugins/SymbolFile/NativePDB/CompileUnitIndex.cpp
index d15c0ee99f96..e2e06491e8c1 100644
--- a/lldb/source/Plugins/SymbolFile/NativePDB/CompileUnitIndex.cpp
+++ b/lldb/source/Plugins/SymbolFile/NativePDB/CompileUnitIndex.cpp
@@ -66,7 +66,7 @@ static void ParseBuildInfo(PdbIndex &index, const CVSymbol &sym,
   // S_BUILDINFO just points to an LF_BUILDINFO in the IPI stream.  Let's do
   // a little extra work to pull out the LF_BUILDINFO.
   LazyRandomTypeCollection &types = index.ipi().typeCollection();
-  llvm::Optional<CVType> cvt = types.tryGetType(bis.BuildId);
+  std::optional<CVType> cvt = types.tryGetType(bis.BuildId);
 
   if (!cvt || cvt->kind() != LF_BUILDINFO)
     return;
diff --git a/llvm/include/llvm/BinaryFormat/Dwarf.h b/llvm/include/llvm/BinaryFormat/Dwarf.h
index e288c5191bdb..2b49c375acb3 100644
--- a/llvm/include/llvm/BinaryFormat/Dwarf.h
+++ b/llvm/include/llvm/BinaryFormat/Dwarf.h
@@ -634,7 +634,7 @@ unsigned AttributeEncodingVendor(TypeKind E);
 unsigned LanguageVendor(SourceLanguage L);
 /// @}
 
-Optional<unsigned> LanguageLowerBound(SourceLanguage L);
+std::optional<unsigned> LanguageLowerBound(SourceLanguage L);
 
 /// The size of a reference determined by the DWARF 32/64-bit format.
 inline uint8_t getDwarfOffsetByteSize(DwarfFormat Format) {
@@ -694,9 +694,10 @@ inline uint8_t getUnitLengthFieldByteSize(DwarfFormat Format) {
 ///
 /// \param Form DWARF form to get the fixed byte size for.
 /// \param Params DWARF parameters to help interpret forms.
-/// \returns Optional<uint8_t> value with the fixed byte size or None if
+/// \returns std::optional<uint8_t> value with the fixed byte size or None if
 /// \p Form doesn't have a fixed byte size.
-Optional<uint8_t> getFixedFormByteSize(dwarf::Form Form, FormParams Params);
+std::optional<uint8_t> getFixedFormByteSize(dwarf::Form Form,
+                                            FormParams Params);
 
 /// Tells whether the specified form is defined in the specified version,
 /// or is an extension if extensions are allowed.
diff --git a/llvm/include/llvm/DebugInfo/CodeView/AppendingTypeTableBuilder.h b/llvm/include/llvm/DebugInfo/CodeView/AppendingTypeTableBuilder.h
index d474173973b5..fa2277343d5d 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/AppendingTypeTableBuilder.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/AppendingTypeTableBuilder.h
@@ -36,8 +36,8 @@ public:
   ~AppendingTypeTableBuilder();
 
   // TypeCollection overrides
-  Optional<TypeIndex> getFirst() override;
-  Optional<TypeIndex> getNext(TypeIndex Prev) override;
+  std::optional<TypeIndex> getFirst() override;
+  std::optional<TypeIndex> getNext(TypeIndex Prev) override;
   CVType getType(TypeIndex Index) override;
   StringRef getTypeName(TypeIndex Index) override;
   bool contains(TypeIndex Index) override;
diff --git a/llvm/include/llvm/DebugInfo/CodeView/CVSymbolVisitor.h b/llvm/include/llvm/DebugInfo/CodeView/CVSymbolVisitor.h
index ef44b622d955..c629018fd109 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/CVSymbolVisitor.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/CVSymbolVisitor.h
@@ -19,9 +19,9 @@ class SymbolVisitorCallbacks;
 class CVSymbolVisitor {
 public:
   struct FilterOptions {
-    llvm::Optional<uint32_t> SymbolOffset;
-    llvm::Optional<uint32_t> ParentRecursiveDepth;
-    llvm::Optional<uint32_t> ChildRecursiveDepth;
+    std::optional<uint32_t> SymbolOffset;
+    std::optional<uint32_t> ParentRecursiveDepth;
+    std::optional<uint32_t> ChildRecursiveDepth;
   };
 
   CVSymbolVisitor(SymbolVisitorCallbacks &Callbacks);
diff --git a/llvm/include/llvm/DebugInfo/CodeView/CodeViewRecordIO.h b/llvm/include/llvm/DebugInfo/CodeView/CodeViewRecordIO.h
index ccaf6506abde..5a2d0c6c049a 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/CodeViewRecordIO.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/CodeViewRecordIO.h
@@ -10,7 +10,6 @@
 #define LLVM_DEBUGINFO_CODEVIEW_CODEVIEWRECORDIO_H
 
 #include "llvm/ADT/None.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/DebugInfo/CodeView/CodeViewError.h"
@@ -63,7 +62,7 @@ public:
   explicit CodeViewRecordIO(CodeViewRecordStreamer &Streamer)
       : Streamer(&Streamer) {}
 
-  Error beginRecord(Optional<uint32_t> MaxLength);
+  Error beginRecord(std::optional<uint32_t> MaxLength);
   Error endRecord();
 
   Error mapInteger(TypeIndex &TypeInd, const Twine &Comment = "");
@@ -245,9 +244,9 @@ private:
 
   struct RecordLimit {
     uint32_t BeginOffset;
-    Optional<uint32_t> MaxLength;
+    std::optional<uint32_t> MaxLength;
 
-    Optional<uint32_t> bytesRemaining(uint32_t CurrentOffset) const {
+    std::optional<uint32_t> bytesRemaining(uint32_t CurrentOffset) const {
       if (!MaxLength)
         return std::nullopt;
       assert(CurrentOffset >= BeginOffset);
diff --git a/llvm/include/llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h b/llvm/include/llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h
index 0f83ae370a1e..84cef520a2f4 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h
@@ -10,7 +10,6 @@
 #define LLVM_DEBUGINFO_CODEVIEW_CONTINUATIONRECORDBUILDER_H
 
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/DebugInfo/CodeView/CVRecord.h"
 #include "llvm/DebugInfo/CodeView/TypeRecordMapping.h"
@@ -26,7 +25,7 @@ enum class ContinuationRecordKind { FieldList, MethodOverloadList };
 
 class ContinuationRecordBuilder {
   SmallVector<uint32_t, 4> SegmentOffsets;
-  Optional<ContinuationRecordKind> Kind;
+  std::optional<ContinuationRecordKind> Kind;
   AppendingBinaryByteStream Buffer;
   BinaryStreamWriter SegmentWriter;
   TypeRecordMapping Mapping;
@@ -36,7 +35,7 @@ class ContinuationRecordBuilder {
 
   void insertSegmentEnd(uint32_t Offset);
   CVType createSegmentRecord(uint32_t OffBegin, uint32_t OffEnd,
-                             Optional<TypeIndex> RefersTo);
+                             std::optional<TypeIndex> RefersTo);
 
 public:
   ContinuationRecordBuilder();
diff --git a/llvm/include/llvm/DebugInfo/CodeView/GlobalTypeTableBuilder.h b/llvm/include/llvm/DebugInfo/CodeView/GlobalTypeTableBuilder.h
index d592bde18bae..18f16bc66a77 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/GlobalTypeTableBuilder.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/GlobalTypeTableBuilder.h
@@ -49,8 +49,8 @@ public:
   ~GlobalTypeTableBuilder();
 
   // TypeCollection overrides
-  Optional<TypeIndex> getFirst() override;
-  Optional<TypeIndex> getNext(TypeIndex Prev) override;
+  std::optional<TypeIndex> getFirst() override;
+  std::optional<TypeIndex> getNext(TypeIndex Prev) override;
   CVType getType(TypeIndex Index) override;
   StringRef getTypeName(TypeIndex Index) override;
   bool contains(TypeIndex Index) override;
diff --git a/llvm/include/llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h b/llvm/include/llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h
index ddbb4e3c5e6c..240f7092140c 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h
@@ -10,7 +10,6 @@
 #define LLVM_DEBUGINFO_CODEVIEW_LAZYRANDOMTYPECOLLECTION_H
 
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/DebugInfo/CodeView/TypeCollection.h"
 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
@@ -69,15 +68,15 @@ public:
 
   uint32_t getOffsetOfType(TypeIndex Index);
 
-  Optional<CVType> tryGetType(TypeIndex Index);
+  std::optional<CVType> tryGetType(TypeIndex Index);
 
   CVType getType(TypeIndex Index) override;
   StringRef getTypeName(TypeIndex Index) override;
   bool contains(TypeIndex Index) override;
   uint32_t size() override;
   uint32_t capacity() override;
-  Optional<TypeIndex> getFirst() override;
-  Optional<TypeIndex> getNext(TypeIndex Prev) override;
+  std::optional<TypeIndex> getFirst() override;
+  std::optional<TypeIndex> getNext(TypeIndex Prev) override;
   bool replaceType(TypeIndex &Index, CVType Data, bool Stabilize) override;
 
 private:
diff --git a/llvm/include/llvm/DebugInfo/CodeView/MergingTypeTableBuilder.h b/llvm/include/llvm/DebugInfo/CodeView/MergingTypeTableBuilder.h
index 1965aab9b5cc..10bc8f60613c 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/MergingTypeTableBuilder.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/MergingTypeTableBuilder.h
@@ -45,8 +45,8 @@ public:
   ~MergingTypeTableBuilder();
 
   // TypeCollection overrides
-  Optional<TypeIndex> getFirst() override;
-  Optional<TypeIndex> getNext(TypeIndex Prev) override;
+  std::optional<TypeIndex> getFirst() override;
+  std::optional<TypeIndex> getNext(TypeIndex Prev) override;
   CVType getType(TypeIndex Index) override;
   StringRef getTypeName(TypeIndex Index) override;
   bool contains(TypeIndex Index) override;
diff --git a/llvm/include/llvm/DebugInfo/CodeView/SymbolRecord.h b/llvm/include/llvm/DebugInfo/CodeView/SymbolRecord.h
index 9513e19a330a..3ddcf9c57390 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/SymbolRecord.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/SymbolRecord.h
@@ -11,7 +11,6 @@
 
 #include "llvm/ADT/APSInt.h"
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/iterator.h"
 #include "llvm/ADT/iterator_range.h"
@@ -324,7 +323,7 @@ private:
     return true;
   }
 
-  Optional<DecodedAnnotation> Current;
+  std::optional<DecodedAnnotation> Current;
   ArrayRef<uint8_t> Data;
   ArrayRef<uint8_t> Next;
 };
diff --git a/llvm/include/llvm/DebugInfo/CodeView/SymbolRecordMapping.h b/llvm/include/llvm/DebugInfo/CodeView/SymbolRecordMapping.h
index 34368b6185d6..30e9c626c205 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/SymbolRecordMapping.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/SymbolRecordMapping.h
@@ -35,7 +35,7 @@ public:
 #include "llvm/DebugInfo/CodeView/CodeViewSymbols.def"
 
 private:
-  Optional<SymbolKind> Kind;
+  std::optional<SymbolKind> Kind;
 
   CodeViewRecordIO IO;
   CodeViewContainer Container;
diff --git a/llvm/include/llvm/DebugInfo/CodeView/SymbolSerializer.h b/llvm/include/llvm/DebugInfo/CodeView/SymbolSerializer.h
index 53986f9a6db6..df52b374f72d 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/SymbolSerializer.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/SymbolSerializer.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_CODEVIEW_SYMBOLSERIALIZER_H
 #define LLVM_DEBUGINFO_CODEVIEW_SYMBOLSERIALIZER_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/CodeView/CVRecord.h"
 #include "llvm/DebugInfo/CodeView/CodeView.h"
 #include "llvm/DebugInfo/CodeView/RecordSerialization.h"
@@ -35,7 +34,7 @@ class SymbolSerializer : public SymbolVisitorCallbacks {
   MutableBinaryByteStream Stream;
   BinaryStreamWriter Writer;
   SymbolRecordMapping Mapping;
-  Optional<SymbolKind> CurrentSymbol;
+  std::optional<SymbolKind> CurrentSymbol;
 
   Error writeRecordPrefix(SymbolKind Kind) {
     RecordPrefix Prefix;
diff --git a/llvm/include/llvm/DebugInfo/CodeView/TypeCollection.h b/llvm/include/llvm/DebugInfo/CodeView/TypeCollection.h
index f643bc4d7451..dd082a72125a 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/TypeCollection.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/TypeCollection.h
@@ -21,8 +21,8 @@ public:
 
   bool empty() { return size() == 0; }
 
-  virtual Optional<TypeIndex> getFirst() = 0;
-  virtual Optional<TypeIndex> getNext(TypeIndex Prev) = 0;
+  virtual std::optional<TypeIndex> getFirst() = 0;
+  virtual std::optional<TypeIndex> getNext(TypeIndex Prev) = 0;
 
   virtual CVType getType(TypeIndex Index) = 0;
   virtual StringRef getTypeName(TypeIndex Index) = 0;
@@ -32,7 +32,7 @@ public:
   virtual bool replaceType(TypeIndex &Index, CVType Data, bool Stabilize) = 0;
 
   template <typename TFunc> void ForEachRecord(TFunc Func) {
-    Optional<TypeIndex> Next = getFirst();
+    std::optional<TypeIndex> Next = getFirst();
 
     while (Next) {
       TypeIndex N = *Next;
diff --git a/llvm/include/llvm/DebugInfo/CodeView/TypeRecord.h b/llvm/include/llvm/DebugInfo/CodeView/TypeRecord.h
index 01916bd18fb8..1ebc4d47e096 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/TypeRecord.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/TypeRecord.h
@@ -11,7 +11,6 @@
 
 #include "llvm/ADT/APSInt.h"
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/DebugInfo/CodeView/CVRecord.h"
@@ -22,6 +21,7 @@
 #include "llvm/Support/Endian.h"
 #include <algorithm>
 #include <cstdint>
+#include <optional>
 #include <vector>
 
 namespace llvm {
diff --git a/llvm/include/llvm/DebugInfo/CodeView/TypeRecordMapping.h b/llvm/include/llvm/DebugInfo/CodeView/TypeRecordMapping.h
index ed4fc7a75624..26eb7d221679 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/TypeRecordMapping.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/TypeRecordMapping.h
@@ -9,12 +9,12 @@
 #ifndef LLVM_DEBUGINFO_CODEVIEW_TYPERECORDMAPPING_H
 #define LLVM_DEBUGINFO_CODEVIEW_TYPERECORDMAPPING_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/CodeView/CVRecord.h"
 #include "llvm/DebugInfo/CodeView/CodeView.h"
 #include "llvm/DebugInfo/CodeView/CodeViewRecordIO.h"
 #include "llvm/DebugInfo/CodeView/TypeVisitorCallbacks.h"
 #include "llvm/Support/Error.h"
+#include <optional>
 
 namespace llvm {
 class BinaryStreamReader;
@@ -46,8 +46,8 @@ public:
 #include "llvm/DebugInfo/CodeView/CodeViewTypes.def"
 
 private:
-  Optional<TypeLeafKind> TypeKind;
-  Optional<TypeLeafKind> MemberKind;
+  std::optional<TypeLeafKind> TypeKind;
+  std::optional<TypeLeafKind> MemberKind;
 
   CodeViewRecordIO IO;
 };
diff --git a/llvm/include/llvm/DebugInfo/CodeView/TypeStreamMerger.h b/llvm/include/llvm/DebugInfo/CodeView/TypeStreamMerger.h
index 6abf67a27bd1..86edfc4b055f 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/TypeStreamMerger.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/TypeStreamMerger.h
@@ -91,20 +91,20 @@ Error mergeTypeAndIdRecords(MergingTypeTableBuilder &DestIds,
                             MergingTypeTableBuilder &DestTypes,
                             SmallVectorImpl<TypeIndex> &SourceToDest,
                             const CVTypeArray &IdsAndTypes,
-                            Optional<PCHMergerInfo> &PCHInfo);
+                            std::optional<PCHMergerInfo> &PCHInfo);
 
 Error mergeTypeAndIdRecords(GlobalTypeTableBuilder &DestIds,
                             GlobalTypeTableBuilder &DestTypes,
                             SmallVectorImpl<TypeIndex> &SourceToDest,
                             const CVTypeArray &IdsAndTypes,
                             ArrayRef<GloballyHashedType> Hashes,
-                            Optional<PCHMergerInfo> &PCHInfo);
+                            std::optional<PCHMergerInfo> &PCHInfo);
 
 Error mergeTypeRecords(GlobalTypeTableBuilder &Dest,
                        SmallVectorImpl<TypeIndex> &SourceToDest,
                        const CVTypeArray &Types,
                        ArrayRef<GloballyHashedType> Hashes,
-                       Optional<PCHMergerInfo> &PCHInfo);
+                       std::optional<PCHMergerInfo> &PCHInfo);
 
 Error mergeIdRecords(GlobalTypeTableBuilder &Dest, ArrayRef<TypeIndex> Types,
                      SmallVectorImpl<TypeIndex> &SourceToDest,
diff --git a/llvm/include/llvm/DebugInfo/CodeView/TypeTableCollection.h b/llvm/include/llvm/DebugInfo/CodeView/TypeTableCollection.h
index c3008742d2e1..2a389b9ac34e 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/TypeTableCollection.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/TypeTableCollection.h
@@ -21,8 +21,8 @@ class TypeTableCollection : public TypeCollection {
 public:
   explicit TypeTableCollection(ArrayRef<ArrayRef<uint8_t>> Records);
 
-  Optional<TypeIndex> getFirst() override;
-  Optional<TypeIndex> getNext(TypeIndex Prev) override;
+  std::optional<TypeIndex> getFirst() override;
+  std::optional<TypeIndex> getNext(TypeIndex Prev) override;
 
   CVType getType(TypeIndex Index) override;
   StringRef getTypeName(TypeIndex Index) override;
diff --git a/llvm/include/llvm/DebugInfo/DIContext.h b/llvm/include/llvm/DebugInfo/DIContext.h
index 9b278b696073..afc2d5176ebc 100644
--- a/llvm/include/llvm/DebugInfo/DIContext.h
+++ b/llvm/include/llvm/DebugInfo/DIContext.h
@@ -21,6 +21,7 @@
 #include <cassert>
 #include <cstdint>
 #include <memory>
+#include <optional>
 #include <string>
 #include <tuple>
 #include <utility>
@@ -36,11 +37,11 @@ struct DILineInfo {
   std::string FileName;
   std::string FunctionName;
   std::string StartFileName;
-  Optional<StringRef> Source;
+  std::optional<StringRef> Source;
   uint32_t Line = 0;
   uint32_t Column = 0;
   uint32_t StartLine = 0;
-  Optional<uint64_t> StartAddress;
+  std::optional<uint64_t> StartAddress;
 
   // DWARF-specific.
   uint32_t Discriminator = 0;
@@ -125,9 +126,9 @@ struct DILocal {
   std::string Name;
   std::string DeclFile;
   uint64_t DeclLine = 0;
-  Optional<int64_t> FrameOffset;
-  Optional<uint64_t> Size;
-  Optional<uint64_t> TagOffset;
+  std::optional<int64_t> FrameOffset;
+  std::optional<uint64_t> Size;
+  std::optional<uint64_t> TagOffset;
 };
 
 /// A DINameKind is passed to name search methods to specify a
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h
index 3887656ceef6..6d7c5773379e 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_DWARF_DWARFABBREVIATIONDECLARATION_H
 #define LLVM_DEBUGINFO_DWARF_DWARFABBREVIATIONDECLARATION_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/iterator_range.h"
 #include "llvm/BinaryFormat/Dwarf.h"
@@ -31,7 +30,8 @@ public:
         : Attr(A), Form(F), Value(Value) {
       assert(isImplicitConst());
     }
-    AttributeSpec(dwarf::Attribute A, dwarf::Form F, Optional<uint8_t> ByteSize)
+    AttributeSpec(dwarf::Attribute A, dwarf::Form F,
+                  std::optional<uint8_t> ByteSize)
         : Attr(A), Form(F) {
       assert(!isImplicitConst());
       this->ByteSize.HasByteSize = ByteSize.has_value();
@@ -79,7 +79,7 @@ public:
     /// use the DWARFUnit to calculate the size of the Form, like for
     /// DW_AT_address and DW_AT_ref_addr, so this isn't just an accessor for
     /// the ByteSize member.
-    Optional<int64_t> getByteSize(const DWARFUnit &U) const;
+    std::optional<int64_t> getByteSize(const DWARFUnit &U) const;
   };
   using AttributeSpecVector = SmallVector<AttributeSpec, 8>;
 
@@ -128,7 +128,7 @@ public:
   ///
   /// \param attr DWARF attribute to search for.
   /// \returns Optional index of the attribute if found, None otherwise.
-  Optional<uint32_t> findAttributeIndex(dwarf::Attribute attr) const;
+  std::optional<uint32_t> findAttributeIndex(dwarf::Attribute attr) const;
 
   /// Extract a DWARF form value from a DIE specified by DIE offset.
   ///
@@ -140,9 +140,9 @@ public:
   /// \param Attr DWARF attribute to search for.
   /// \param U the DWARFUnit the contains the DIE.
   /// \returns Optional DWARF form value if the attribute was extracted.
-  Optional<DWARFFormValue> getAttributeValue(const uint64_t DIEOffset,
-                                             const dwarf::Attribute Attr,
-                                             const DWARFUnit &U) const;
+  std::optional<DWARFFormValue> getAttributeValue(const uint64_t DIEOffset,
+                                                  const dwarf::Attribute Attr,
+                                                  const DWARFUnit &U) const;
 
   /// Compute an offset from a DIE specified by DIE offset and attribute index.
   ///
@@ -161,7 +161,7 @@ public:
   /// \param Offset offset of the attribute.
   /// \param U the DWARFUnit the contains the DIE.
   /// \returns Optional DWARF form value if the attribute was extracted.
-  Optional<DWARFFormValue>
+  std::optional<DWARFFormValue>
   getAttributeValueFromOffset(uint32_t AttrIndex, uint64_t Offset,
                               const DWARFUnit &U) const;
 
@@ -171,7 +171,7 @@ public:
   // Return an optional byte size of all attribute data in this abbreviation
   // if a constant byte size can be calculated given a DWARFUnit. This allows
   // DWARF parsing to be faster as many DWARF DIEs have a fixed byte size.
-  Optional<size_t> getFixedAttributesByteSize(const DWARFUnit &U) const;
+  std::optional<size_t> getFixedAttributesByteSize(const DWARFUnit &U) const;
 
 private:
   void clear();
@@ -206,7 +206,7 @@ private:
   AttributeSpecVector AttributeSpecs;
   /// If this abbreviation has a fixed byte size then FixedAttributeSize member
   /// variable below will have a value.
-  Optional<FixedSizeInfo> FixedAttributeSize;
+  std::optional<FixedSizeInfo> FixedAttributeSize;
 };
 
 } // end namespace llvm
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h
index 355995bf69b9..aad46b945adf 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h
@@ -53,12 +53,12 @@ public:
     /// Returns the Offset of the Compilation Unit associated with this
     /// Accelerator Entry or None if the Compilation Unit offset is not recorded
     /// in this Accelerator Entry.
-    virtual Optional<uint64_t> getCUOffset() const = 0;
+    virtual std::optional<uint64_t> getCUOffset() const = 0;
 
     /// Returns the Tag of the Debug Info Entry associated with this
     /// Accelerator Entry or None if the Tag is not recorded in this
     /// Accelerator Entry.
-    virtual Optional<dwarf::Tag> getTag() const = 0;
+    virtual std::optional<dwarf::Tag> getTag() const = 0;
 
     /// Returns the raw values of fields in the Accelerator Entry. In general,
     /// these can only be interpreted with the help of the metadata in the
@@ -99,7 +99,8 @@ class AppleAcceleratorTable : public DWARFAcceleratorTable {
     uint64_t DIEOffsetBase;
     SmallVector<std::pair<AtomType, Form>, 3> Atoms;
 
-    Optional<uint64_t> extractOffset(Optional<DWARFFormValue> Value) const;
+    std::optional<uint64_t>
+    extractOffset(std::optional<DWARFFormValue> Value) const;
   };
 
   struct Header Hdr;
@@ -122,19 +123,19 @@ public:
     void extract(const AppleAcceleratorTable &AccelTable, uint64_t *Offset);
 
   public:
-    Optional<uint64_t> getCUOffset() const override;
+    std::optional<uint64_t> getCUOffset() const override;
 
     /// Returns the Section Offset of the Debug Info Entry associated with this
     /// Accelerator Entry or None if the DIE offset is not recorded in this
     /// Accelerator Entry. The returned offset is relative to the start of the
     /// Section containing the DIE.
-    Optional<uint64_t> getDIESectionOffset() const;
+    std::optional<uint64_t> getDIESectionOffset() const;
 
-    Optional<dwarf::Tag> getTag() const override;
+    std::optional<dwarf::Tag> getTag() const override;
 
     /// Returns the value of the Atom in this Accelerator Entry, if the Entry
     /// contains such Atom.
-    Optional<DWARFFormValue> lookup(HeaderData::AtomType Atom) const;
+    std::optional<DWARFFormValue> lookup(HeaderData::AtomType Atom) const;
 
     friend class AppleAcceleratorTable;
     friend class ValueIterator;
@@ -287,8 +288,8 @@ public:
     Entry(const NameIndex &NameIdx, const Abbrev &Abbr);
 
   public:
-    Optional<uint64_t> getCUOffset() const override;
-    Optional<dwarf::Tag> getTag() const override { return tag(); }
+    std::optional<uint64_t> getCUOffset() const override;
+    std::optional<dwarf::Tag> getTag() const override { return tag(); }
 
     /// Returns the Index into the Compilation Unit list of the owning Name
     /// Index or None if this Accelerator Entry does not have an associated
@@ -298,14 +299,14 @@ public:
     /// just a single Compilation Unit are implicitly associated with that unit,
     /// so this function will return 0 even without an explicit
     /// DW_IDX_compile_unit attribute.
-    Optional<uint64_t> getCUIndex() const;
+    std::optional<uint64_t> getCUIndex() const;
 
     /// .debug_names-specific getter, which always succeeds (DWARF v5 index
     /// entries always have a tag).
     dwarf::Tag tag() const { return Abbr->Tag; }
 
     /// Returns the Offset of the DIE within the containing CU or TU.
-    Optional<uint64_t> getDIEUnitOffset() const;
+    std::optional<uint64_t> getDIEUnitOffset() const;
 
     /// Return the Abbreviation that can be used to interpret the raw values of
     /// this Accelerator Entry.
@@ -313,7 +314,7 @@ public:
 
     /// Returns the value of the Index Attribute in this Accelerator Entry, if
     /// the Entry contains such Attribute.
-    Optional<DWARFFormValue> lookup(dwarf::Index Index) const;
+    std::optional<DWARFFormValue> lookup(dwarf::Index Index) const;
 
     void dump(ScopedPrinter &W) const;
 
@@ -406,7 +407,7 @@ public:
     void dumpAbbreviations(ScopedPrinter &W) const;
     bool dumpEntry(ScopedPrinter &W, uint64_t *Offset) const;
     void dumpName(ScopedPrinter &W, const NameTableEntry &NTE,
-                  Optional<uint32_t> Hash) const;
+                  std::optional<uint32_t> Hash) const;
     void dumpBucket(ScopedPrinter &W, uint32_t Bucket) const;
 
     Expected<AttributeEncoding> extractAttributeEncoding(uint64_t *Offset);
@@ -491,13 +492,13 @@ public:
     /// (searches all name indices).
     bool IsLocal;
 
-    Optional<Entry> CurrentEntry;
+    std::optional<Entry> CurrentEntry;
     uint64_t DataOffset = 0; ///< Offset into the section.
     std::string Key;         ///< The Key we are searching for.
-    Optional<uint32_t> Hash; ///< Hash of Key, if it has been computed.
+    std::optional<uint32_t> Hash; ///< Hash of Key, if it has been computed.
 
     bool getEntryAtCurrentOffset();
-    Optional<uint64_t> findEntryOffsetInCurrentIndex();
+    std::optional<uint64_t> findEntryOffsetInCurrentIndex();
     bool findInCurrentIndex();
     void searchFromStartOfCurrentIndex();
     void next();
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h
index bf591ed554c6..5dc000163e7d 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h
@@ -46,7 +46,7 @@ class DWARFUnitIndex;
 /// information parsing. The actual data is supplied through DWARFObj.
 class DWARFContext : public DIContext {
   DWARFUnitVector NormalUnits;
-  Optional<DenseMap<uint64_t, DWARFTypeUnit*>> NormalTypeUnits;
+  std::optional<DenseMap<uint64_t, DWARFTypeUnit *>> NormalTypeUnits;
   std::unique_ptr<DWARFUnitIndex> CUIndex;
   std::unique_ptr<DWARFGdbIndex> GdbIndex;
   std::unique_ptr<DWARFUnitIndex> TUIndex;
@@ -65,7 +65,7 @@ class DWARFContext : public DIContext {
   std::unique_ptr<AppleAcceleratorTable> AppleObjC;
 
   DWARFUnitVector DWOUnits;
-  Optional<DenseMap<uint64_t, DWARFTypeUnit*>> DWOTypeUnits;
+  std::optional<DenseMap<uint64_t, DWARFTypeUnit *>> DWOTypeUnits;
   std::unique_ptr<DWARFDebugAbbrev> AbbrevDWO;
   std::unique_ptr<DWARFDebugMacro> MacinfoDWO;
   std::unique_ptr<DWARFDebugMacro> MacroDWO;
@@ -132,10 +132,10 @@ public:
   /// Dump a textual representation to \p OS. If any \p DumpOffsets are present,
   /// dump only the record at the specified offset.
   void dump(raw_ostream &OS, DIDumpOptions DumpOpts,
-            std::array<Optional<uint64_t>, DIDT_ID_Count> DumpOffsets);
+            std::array<std::optional<uint64_t>, DIDT_ID_Count> DumpOffsets);
 
   void dump(raw_ostream &OS, DIDumpOptions DumpOpts) override {
-    std::array<Optional<uint64_t>, DIDT_ID_Count> DumpOffsets;
+    std::array<std::optional<uint64_t>, DIDT_ID_Count> DumpOffsets;
     dump(OS, DumpOpts, DumpOffsets);
   }
 
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDataExtractor.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDataExtractor.h
index 49749201af99..e94fa7bf5590 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDataExtractor.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDataExtractor.h
@@ -81,8 +81,8 @@ public:
   /// There is a DWARF encoding that uses a PC-relative adjustment.
   /// For these values, \p AbsPosOffset is used to fix them, which should
   /// reflect the absolute address of this pointer.
-  Optional<uint64_t> getEncodedPointer(uint64_t *Offset, uint8_t Encoding,
-                                       uint64_t AbsPosOffset = 0) const;
+  std::optional<uint64_t> getEncodedPointer(uint64_t *Offset, uint8_t Encoding,
+                                            uint64_t AbsPosOffset = 0) const;
 };
 
 } // end namespace llvm
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h
index 882aa69d9ccb..52a88f2c390a 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h
@@ -59,7 +59,7 @@ class DWARFDebugAbbrev {
 
   mutable DWARFAbbreviationDeclarationSetMap AbbrDeclSets;
   mutable DWARFAbbreviationDeclarationSetMap::const_iterator PrevAbbrOffsetPos;
-  mutable Optional<DataExtractor> Data;
+  mutable std::optional<DataExtractor> Data;
 
 public:
   DWARFDebugAbbrev();
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugAddr.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugAddr.h
index 67d9ce1476dd..9549a5789488 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugAddr.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugAddr.h
@@ -70,7 +70,7 @@ public:
 
   /// Return the full length of this table, including the length field.
   /// Return None if the length cannot be identified reliably.
-  Optional<uint64_t> getFullLength() const;
+  std::optional<uint64_t> getFullLength() const;
 
   /// Return the DWARF format of this table.
   dwarf::DwarfFormat getFormat() const { return Format; }
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h
index 75a1a0b05b2a..9dfe95aa7131 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h
@@ -67,10 +67,10 @@ private:
   Location Kind;   /// The type of the location that describes how to unwind it.
   uint32_t RegNum; /// The register number for Kind == RegPlusOffset.
   int32_t Offset;  /// The offset for Kind == CFAPlusOffset or RegPlusOffset.
-  Optional<uint32_t> AddrSpace; /// The address space for Kind == RegPlusOffset
-                                /// for CFA.
-  Optional<DWARFExpression> Expr; /// The DWARF expression for Kind ==
-                                  /// DWARFExpression.
+  std::optional<uint32_t> AddrSpace;   /// The address space for Kind ==
+                                       /// RegPlusOffset for CFA.
+  std::optional<DWARFExpression> Expr; /// The DWARF expression for Kind ==
+                                       /// DWARFExpression.
   bool Dereference; /// If true, the resulting location must be dereferenced
                     /// after the location value is computed.
 
@@ -80,8 +80,8 @@ private:
       : Kind(K), RegNum(InvalidRegisterNumber), Offset(0),
         AddrSpace(std::nullopt), Dereference(false) {}
 
-  UnwindLocation(Location K, uint32_t Reg, int32_t Off, Optional<uint32_t> AS,
-                 bool Deref)
+  UnwindLocation(Location K, uint32_t Reg, int32_t Off,
+                 std::optional<uint32_t> AS, bool Deref)
       : Kind(K), RegNum(Reg), Offset(Off), AddrSpace(AS), Dereference(Deref) {}
 
   UnwindLocation(DWARFExpression E, bool Deref)
@@ -117,10 +117,10 @@ public:
   /// false.
   static UnwindLocation
   createIsRegisterPlusOffset(uint32_t Reg, int32_t Off,
-                             Optional<uint32_t> AddrSpace = std::nullopt);
+                             std::optional<uint32_t> AddrSpace = std::nullopt);
   static UnwindLocation
   createAtRegisterPlusOffset(uint32_t Reg, int32_t Off,
-                             Optional<uint32_t> AddrSpace = std::nullopt);
+                             std::optional<uint32_t> AddrSpace = std::nullopt);
   /// Create a location whose value is the result of evaluating a DWARF
   /// expression. This allows complex expressions to be evaluated in order to
   /// unwind a register or CFA value.
@@ -149,7 +149,9 @@ public:
   // DW_CFA_AARCH64_negate_ra_state).
   void setConstant(int32_t Value) { Offset = Value; }
 
-  Optional<DWARFExpression> getDWARFExpressionBytes() const { return Expr; }
+  std::optional<DWARFExpression> getDWARFExpressionBytes() const {
+    return Expr;
+  }
   /// Dump a location expression as text and use the register information if
   /// some is provided.
   ///
@@ -187,7 +189,7 @@ public:
   ///
   /// \returns A location if one is available for \a RegNum, or llvm::None
   /// otherwise.
-  Optional<UnwindLocation> getRegisterLocation(uint32_t RegNum) const {
+  std::optional<UnwindLocation> getRegisterLocation(uint32_t RegNum) const {
     auto Pos = Locations.find(RegNum);
     if (Pos == Locations.end())
       return std::nullopt;
@@ -253,7 +255,7 @@ raw_ostream &operator<<(raw_ostream &OS, const RegisterLocations &RL);
 class UnwindRow {
   /// The address will be valid when parsing the instructions in a FDE. If
   /// invalid, this object represents the initial instructions of a CIE.
-  Optional<uint64_t> Address; ///< Address for row in FDE, invalid for CIE.
+  std::optional<uint64_t> Address; ///< Address for row in FDE, invalid for CIE.
   UnwindLocation CFAValue;    ///< How to unwind the Call Frame Address (CFA).
   RegisterLocations RegLocs;  ///< How to unwind all registers in this list.
 
@@ -373,7 +375,7 @@ private:
   RowContainer Rows;
   /// The end address when data is extracted from a FDE. This value will be
   /// invalid when a UnwindTable is extracted from a CIE.
-  Optional<uint64_t> EndAddress;
+  std::optional<uint64_t> EndAddress;
 
   /// Parse the information in the CFIProgram and update the CurrRow object
   /// that the state machine describes.
@@ -416,7 +418,7 @@ public:
     uint8_t Opcode;
     Operands Ops;
     // Associated DWARF expression in case this instruction refers to one
-    Optional<DWARFExpression> Expression;
+    std::optional<DWARFExpression> Expression;
 
     Expected<uint64_t> getOperandAsUnsigned(const CFIProgram &CFIP,
                                             uint32_t OperandIdx) const;
@@ -573,8 +575,8 @@ public:
       uint8_t SegmentDescriptorSize, uint64_t CodeAlignmentFactor,
       int64_t DataAlignmentFactor, uint64_t ReturnAddressRegister,
       SmallString<8> AugmentationData, uint32_t FDEPointerEncoding,
-      uint32_t LSDAPointerEncoding, Optional<uint64_t> Personality,
-      Optional<uint32_t> PersonalityEnc, Triple::ArchType Arch)
+      uint32_t LSDAPointerEncoding, std::optional<uint64_t> Personality,
+      std::optional<uint32_t> PersonalityEnc, Triple::ArchType Arch)
       : FrameEntry(FK_CIE, IsDWARF64, Offset, Length, CodeAlignmentFactor,
                    DataAlignmentFactor, Arch),
         Version(Version), Augmentation(std::move(Augmentation)),
@@ -594,8 +596,10 @@ public:
   int64_t getDataAlignmentFactor() const { return DataAlignmentFactor; }
   uint8_t getVersion() const { return Version; }
   uint64_t getReturnAddressRegister() const { return ReturnAddressRegister; }
-  Optional<uint64_t> getPersonalityAddress() const { return Personality; }
-  Optional<uint32_t> getPersonalityEncoding() const { return PersonalityEnc; }
+  std::optional<uint64_t> getPersonalityAddress() const { return Personality; }
+  std::optional<uint32_t> getPersonalityEncoding() const {
+    return PersonalityEnc;
+  }
 
   uint32_t getFDEPointerEncoding() const { return FDEPointerEncoding; }
 
@@ -618,8 +622,8 @@ private:
   const SmallString<8> AugmentationData;
   const uint32_t FDEPointerEncoding;
   const uint32_t LSDAPointerEncoding;
-  const Optional<uint64_t> Personality;
-  const Optional<uint32_t> PersonalityEnc;
+  const std::optional<uint64_t> Personality;
+  const std::optional<uint32_t> PersonalityEnc;
 };
 
 /// DWARF Frame Description Entry (FDE)
@@ -627,11 +631,10 @@ class FDE : public FrameEntry {
 public:
   FDE(bool IsDWARF64, uint64_t Offset, uint64_t Length, uint64_t CIEPointer,
       uint64_t InitialLocation, uint64_t AddressRange, CIE *Cie,
-      Optional<uint64_t> LSDAAddress, Triple::ArchType Arch)
+      std::optional<uint64_t> LSDAAddress, Triple::ArchType Arch)
       : FrameEntry(FK_FDE, IsDWARF64, Offset, Length,
                    Cie ? Cie->getCodeAlignmentFactor() : 0,
-                   Cie ? Cie->getDataAlignmentFactor() : 0,
-                   Arch),
+                   Cie ? Cie->getDataAlignmentFactor() : 0, Arch),
         CIEPointer(CIEPointer), InitialLocation(InitialLocation),
         AddressRange(AddressRange), LinkedCIE(Cie), LSDAAddress(LSDAAddress) {}
 
@@ -640,7 +643,7 @@ public:
   const CIE *getLinkedCIE() const { return LinkedCIE; }
   uint64_t getInitialLocation() const { return InitialLocation; }
   uint64_t getAddressRange() const { return AddressRange; }
-  Optional<uint64_t> getLSDAAddress() const { return LSDAAddress; }
+  std::optional<uint64_t> getLSDAAddress() const { return LSDAAddress; }
 
   void dump(raw_ostream &OS, DIDumpOptions DumpOpts, const MCRegisterInfo *MRI,
             bool IsEH) const override;
@@ -656,7 +659,7 @@ private:
   const uint64_t InitialLocation;
   const uint64_t AddressRange;
   const CIE *LinkedCIE;
-  const Optional<uint64_t> LSDAAddress;
+  const std::optional<uint64_t> LSDAAddress;
 };
 
 } // end namespace dwarf
@@ -686,7 +689,7 @@ public:
 
   /// Dump the section data into the given stream.
   void dump(raw_ostream &OS, DIDumpOptions DumpOpts, const MCRegisterInfo *MRI,
-            Optional<uint64_t> Offset) const;
+            std::optional<uint64_t> Offset) const;
 
   /// Parse the section from raw data. \p Data is assumed to contain the whole
   /// frame section contents to be parsed.
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h
index 89c042a0287b..7d59f4257b2e 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h
@@ -45,7 +45,7 @@ public:
   uint64_t getOffset() const { return Offset; }
 
   /// Returns index of the parent die.
-  Optional<uint32_t> getParentIdx() const {
+  std::optional<uint32_t> getParentIdx() const {
     if (ParentIdx == UINT32_MAX)
       return std::nullopt;
 
@@ -53,7 +53,7 @@ public:
   }
 
   /// Returns index of the sibling die.
-  Optional<uint32_t> getSiblingIdx() const {
+  std::optional<uint32_t> getSiblingIdx() const {
     if (SiblingIdx == 0)
       return std::nullopt;
 
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h
index a932662ae04e..de9902ae2ebc 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_DWARF_DWARFDEBUGLINE_H
 #define LLVM_DEBUGINFO_DWARF_DWARFDEBUGLINE_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/BinaryFormat/Dwarf.h"
 #include "llvm/DebugInfo/DIContext.h"
@@ -114,7 +113,7 @@ public:
 
     bool hasFileAtIndex(uint64_t FileIndex) const;
 
-    Optional<uint64_t> getLastValidFileIndex() const;
+    std::optional<uint64_t> getLastValidFileIndex() const;
 
     bool
     getFileNameByIndex(uint64_t FileIndex, StringRef CompDir,
@@ -246,7 +245,7 @@ public:
       return Prologue.hasFileAtIndex(FileIndex);
     }
 
-    Optional<uint64_t> getLastValidFileIndex() const {
+    std::optional<uint64_t> getLastValidFileIndex() const {
       return Prologue.getLastValidFileIndex();
     }
 
@@ -294,7 +293,7 @@ public:
   private:
     uint32_t findRowInSeq(const DWARFDebugLine::Sequence &Seq,
                           object::SectionedAddress Address) const;
-    Optional<StringRef>
+    std::optional<StringRef>
     getSourceByIndex(uint64_t FileIndex,
                      DILineInfoSpecifier::FileLineInfoKind Kind) const;
 
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLoc.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLoc.h
index 90e009e514d4..74638fc180b5 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLoc.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLoc.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_DWARF_DWARFDEBUGLOC_H
 #define LLVM_DEBUGINFO_DWARF_DWARFDEBUGLOC_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
 #include "llvm/Support/Errc.h"
@@ -66,14 +65,15 @@ public:
   /// can attempt to parse another list after the current one (\p Offset will be
   /// updated to point past the end of the current list).
   bool dumpLocationList(uint64_t *Offset, raw_ostream &OS,
-                        Optional<object::SectionedAddress> BaseAddr,
+                        std::optional<object::SectionedAddress> BaseAddr,
                         const MCRegisterInfo *MRI, const DWARFObject &Obj,
                         DWARFUnit *U, DIDumpOptions DumpOpts,
                         unsigned Indent) const;
 
   Error visitAbsoluteLocationList(
-      uint64_t Offset, Optional<object::SectionedAddress> BaseAddr,
-      std::function<Optional<object::SectionedAddress>(uint32_t)> LookupAddr,
+      uint64_t Offset, std::optional<object::SectionedAddress> BaseAddr,
+      std::function<std::optional<object::SectionedAddress>(uint32_t)>
+          LookupAddr,
       function_ref<bool(Expected<DWARFLocationExpression>)> Callback) const;
 
   const DWARFDataExtractor &getData() { return Data; }
@@ -111,7 +111,7 @@ public:
   /// Print the location lists found within the debug_loc section.
   void dump(raw_ostream &OS, const MCRegisterInfo *RegInfo,
             const DWARFObject &Obj, DIDumpOptions DumpOpts,
-            Optional<uint64_t> Offset) const;
+            std::optional<uint64_t> Offset) const;
 
   Error visitLocationList(
       uint64_t *Offset,
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugMacro.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugMacro.h
index 25be64d064bb..cc32e7f24125 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugMacro.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugMacro.h
@@ -125,8 +125,8 @@ public:
 private:
   /// Parse the debug_macinfo/debug_macro section accessible via the 'MacroData'
   /// parameter.
-  Error parseImpl(Optional<DWARFUnitVector::compile_unit_range> Units,
-                  Optional<DataExtractor> StringExtractor,
+  Error parseImpl(std::optional<DWARFUnitVector::compile_unit_range> Units,
+                  std::optional<DataExtractor> StringExtractor,
                   DWARFDataExtractor Data, bool IsMacro);
 };
 
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h
index f4aeac1bb9db..02bb5f0a3d95 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h
@@ -72,7 +72,7 @@ public:
   /// list. Has to be passed base address of the compile unit referencing this
   /// range list.
   DWARFAddressRangesVector
-  getAbsoluteRanges(llvm::Optional<object::SectionedAddress> BaseAddr) const;
+  getAbsoluteRanges(std::optional<object::SectionedAddress> BaseAddr) const;
 };
 
 } // end namespace llvm
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugRnglists.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugRnglists.h
index 13f018f53fa1..8ddd9cab2364 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugRnglists.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugRnglists.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_DWARF_DWARFDEBUGRNGLISTS_H
 #define LLVM_DEBUGINFO_DWARF_DWARFDEBUGRNGLISTS_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLFunctionalExtras.h"
 #include "llvm/BinaryFormat/Dwarf.h"
 #include "llvm/DebugInfo/DWARF/DWARFAddressRange.h"
@@ -37,10 +36,11 @@ struct RangeListEntry : public DWARFListEntryBase {
   uint64_t Value1;
 
   Error extract(DWARFDataExtractor Data, uint64_t *OffsetPtr);
-  void dump(raw_ostream &OS, uint8_t AddrSize, uint8_t MaxEncodingStringLength,
-            uint64_t &CurrentBase, DIDumpOptions DumpOpts,
-            llvm::function_ref<Optional<object::SectionedAddress>(uint32_t)>
-                LookupPooledAddress) const;
+  void
+  dump(raw_ostream &OS, uint8_t AddrSize, uint8_t MaxEncodingStringLength,
+       uint64_t &CurrentBase, DIDumpOptions DumpOpts,
+       llvm::function_ref<std::optional<object::SectionedAddress>(uint32_t)>
+           LookupPooledAddress) const;
   bool isSentinel() const { return EntryKind == dwarf::DW_RLE_end_of_list; }
 };
 
@@ -48,15 +48,14 @@ struct RangeListEntry : public DWARFListEntryBase {
 class DWARFDebugRnglist : public DWARFListType<RangeListEntry> {
 public:
   /// Build a DWARFAddressRangesVector from a rangelist.
-  DWARFAddressRangesVector
-  getAbsoluteRanges(Optional<object::SectionedAddress> BaseAddr,
-                    uint8_t AddressByteSize,
-                    function_ref<Optional<object::SectionedAddress>(uint32_t)>
-                        LookupPooledAddress) const;
+  DWARFAddressRangesVector getAbsoluteRanges(
+      std::optional<object::SectionedAddress> BaseAddr, uint8_t AddressByteSize,
+      function_ref<std::optional<object::SectionedAddress>(uint32_t)>
+          LookupPooledAddress) const;
 
   /// Build a DWARFAddressRangesVector from a rangelist.
   DWARFAddressRangesVector
-  getAbsoluteRanges(llvm::Optional<object::SectionedAddress> BaseAddr,
+  getAbsoluteRanges(std::optional<object::SectionedAddress> BaseAddr,
                     DWARFUnit &U) const;
 };
 
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDie.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDie.h
index 149c5ef4e493..90f59138fc19 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDie.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDie.h
@@ -10,7 +10,6 @@
 #define LLVM_DEBUGINFO_DWARF_DWARFDIE_H
 
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/iterator.h"
 #include "llvm/ADT/iterator_range.h"
 #include "llvm/BinaryFormat/Dwarf.h"
@@ -139,7 +138,7 @@ public:
   /// \param Attr the attribute to extract.
   /// \returns an optional DWARFFormValue that will have the form value if the
   /// attribute was successfully extracted.
-  Optional<DWARFFormValue> find(dwarf::Attribute Attr) const;
+  std::optional<DWARFFormValue> find(dwarf::Attribute Attr) const;
 
   /// Extract the first value of any attribute in Attrs from this DIE.
   ///
@@ -152,7 +151,7 @@ public:
   /// \returns an optional that has a valid DWARFFormValue for the first
   /// matching attribute in Attrs, or None if none of the attributes in Attrs
   /// exist in this DIE.
-  Optional<DWARFFormValue> find(ArrayRef<dwarf::Attribute> Attrs) const;
+  std::optional<DWARFFormValue> find(ArrayRef<dwarf::Attribute> Attrs) const;
 
   /// Extract the first value of any attribute in Attrs from this DIE and
   /// recurse into any DW_AT_specification or DW_AT_abstract_origin referenced
@@ -163,7 +162,7 @@ public:
   /// matching attribute in Attrs, or None if none of the attributes in Attrs
   /// exist in this DIE or in any DW_AT_specification or DW_AT_abstract_origin
   /// DIEs.
-  Optional<DWARFFormValue>
+  std::optional<DWARFFormValue>
   findRecursively(ArrayRef<dwarf::Attribute> Attrs) const;
 
   /// Extract the specified attribute from this DIE as the referenced DIE.
@@ -190,8 +189,8 @@ public:
   /// or DW_AT_GNU_ranges_base attribute.
   ///
   /// \returns anm optional absolute section offset value for the attribute.
-  Optional<uint64_t> getRangesBaseAttribute() const;
-  Optional<uint64_t> getLocBaseAttribute() const;
+  std::optional<uint64_t> getRangesBaseAttribute() const;
+  std::optional<uint64_t> getLocBaseAttribute() const;
 
   /// Get the DW_AT_high_pc attribute value as an address.
   ///
@@ -203,7 +202,7 @@ public:
   ///
   /// \param LowPC the low PC that might be needed to calculate the high PC.
   /// \returns an optional address value for the attribute.
-  Optional<uint64_t> getHighPC(uint64_t LowPC) const;
+  std::optional<uint64_t> getHighPC(uint64_t LowPC) const;
 
   /// Retrieves DW_AT_low_pc and DW_AT_high_pc from CU.
   /// Returns true if both attributes are present.
@@ -285,7 +284,7 @@ public:
   /// \param PointerSize the pointer size of the containing CU.
   /// \returns if this is a type DIE, or this DIE contains a DW_AT_type, returns
   /// the size of the type.
-  Optional<uint64_t> getTypeSize(uint64_t PointerSize);
+  std::optional<uint64_t> getTypeSize(uint64_t PointerSize);
 
   class iterator;
 
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFExpression.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFExpression.h
index 0c9789339660..6e5a16f635c8 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFExpression.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFExpression.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_DWARF_DWARFEXPRESSION_H
 #define LLVM_DEBUGINFO_DWARF_DWARFEXPRESSION_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/iterator.h"
 #include "llvm/BinaryFormat/Dwarf.h"
@@ -102,7 +101,7 @@ public:
 
   private:
     bool extract(DataExtractor Data, uint8_t AddressSize, uint64_t Offset,
-                 Optional<dwarf::DwarfFormat> Format);
+                 std::optional<dwarf::DwarfFormat> Format);
   };
 
   /// An iterator to go through the expression operations.
@@ -140,7 +139,7 @@ public:
   };
 
   DWARFExpression(DataExtractor Data, uint8_t AddressSize,
-                  Optional<dwarf::DwarfFormat> Format = std::nullopt)
+                  std::optional<dwarf::DwarfFormat> Format = std::nullopt)
       : Data(Data), AddressSize(AddressSize), Format(Format) {
     assert(AddressSize == 8 || AddressSize == 4 || AddressSize == 2);
   }
@@ -172,7 +171,7 @@ public:
 private:
   DataExtractor Data;
   uint8_t AddressSize;
-  Optional<dwarf::DwarfFormat> Format;
+  std::optional<dwarf::DwarfFormat> Format;
 };
 
 inline bool operator==(const DWARFExpression::iterator &LHS,
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFFormValue.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
index 4969e671609f..e9944a1fbee6 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
@@ -11,7 +11,6 @@
 
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/None.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/BinaryFormat/Dwarf.h"
 #include "llvm/DebugInfo/DIContext.h"
 #include "llvm/Support/DataExtractor.h"
@@ -106,21 +105,21 @@ public:
 
   /// getAsFoo functions below return the extracted value as Foo if only
   /// DWARFFormValue has form class is suitable for representing Foo.
-  Optional<uint64_t> getAsReference() const;
+  std::optional<uint64_t> getAsReference() const;
   struct UnitOffset {
     DWARFUnit *Unit;
     uint64_t Offset;
   };
-  Optional<UnitOffset> getAsRelativeReference() const;
-  Optional<uint64_t> getAsUnsignedConstant() const;
-  Optional<int64_t> getAsSignedConstant() const;
+  std::optional<UnitOffset> getAsRelativeReference() const;
+  std::optional<uint64_t> getAsUnsignedConstant() const;
+  std::optional<int64_t> getAsSignedConstant() const;
   Expected<const char *> getAsCString() const;
-  Optional<uint64_t> getAsAddress() const;
-  Optional<object::SectionedAddress> getAsSectionedAddress() const;
-  Optional<uint64_t> getAsSectionOffset() const;
-  Optional<ArrayRef<uint8_t>> getAsBlock() const;
-  Optional<uint64_t> getAsCStringOffset() const;
-  Optional<uint64_t> getAsReferenceUVal() const;
+  std::optional<uint64_t> getAsAddress() const;
+  std::optional<object::SectionedAddress> getAsSectionedAddress() const;
+  std::optional<uint64_t> getAsSectionOffset() const;
+  std::optional<ArrayRef<uint8_t>> getAsBlock() const;
+  std::optional<uint64_t> getAsCStringOffset() const;
+  std::optional<uint64_t> getAsReferenceUVal() const;
   /// Correctly extract any file paths from a form value.
   ///
   /// These attributes can be in the from DW_AT_decl_file or DW_AT_call_file
@@ -132,7 +131,7 @@ public:
   ///
   /// \returns A valid string value on success, or llvm::None if the form class
   /// is not FC_Constant, or if the file index is not valid.
-  Optional<std::string>
+  std::optional<std::string>
   getAsFile(DILineInfoSpecifier::FileLineInfoKind Kind) const;
 
   /// Skip a form's value in \p DebugInfoData at the offset specified by
@@ -174,7 +173,8 @@ namespace dwarf {
 /// \param V and optional DWARFFormValue to attempt to extract the value from.
 /// \returns an optional value that contains a value if the form value
 /// was valid and was a string.
-inline Optional<const char *> toString(const Optional<DWARFFormValue> &V) {
+inline std::optional<const char *>
+toString(const std::optional<DWARFFormValue> &V) {
   if (!V)
     return std::nullopt;
   Expected<const char*> E = V->getAsCString();
@@ -190,7 +190,7 @@ inline Optional<const char *> toString(const Optional<DWARFFormValue> &V) {
 /// \param V and optional DWARFFormValue to attempt to extract the value from.
 /// \returns an optional value that contains a value if the form value
 /// was valid and was a string.
-inline StringRef toStringRef(const Optional<DWARFFormValue> &V,
+inline StringRef toStringRef(const std::optional<DWARFFormValue> &V,
                              StringRef Default = {}) {
   if (!V)
     return Default;
@@ -210,7 +210,7 @@ inline StringRef toStringRef(const Optional<DWARFFormValue> &V,
 /// \param Default the default value to return in case of failure.
 /// \returns the string value or Default if the V doesn't have a value or the
 /// form value's encoding wasn't a string.
-inline const char *toString(const Optional<DWARFFormValue> &V,
+inline const char *toString(const std::optional<DWARFFormValue> &V,
                             const char *Default) {
   if (auto E = toString(V))
     return *E;
@@ -222,7 +222,8 @@ inline const char *toString(const Optional<DWARFFormValue> &V,
 /// \param V and optional DWARFFormValue to attempt to extract the value from.
 /// \returns an optional value that contains a value if the form value
 /// was valid and has a unsigned constant form.
-inline Optional<uint64_t> toUnsigned(const Optional<DWARFFormValue> &V) {
+inline std::optional<uint64_t>
+toUnsigned(const std::optional<DWARFFormValue> &V) {
   if (V)
     return V->getAsUnsignedConstant();
   return std::nullopt;
@@ -234,7 +235,7 @@ inline Optional<uint64_t> toUnsigned(const Optional<DWARFFormValue> &V) {
 /// \param Default the default value to return in case of failure.
 /// \returns the extracted unsigned value or Default if the V doesn't have a
 /// value or the form value's encoding wasn't an unsigned constant form.
-inline uint64_t toUnsigned(const Optional<DWARFFormValue> &V,
+inline uint64_t toUnsigned(const std::optional<DWARFFormValue> &V,
                            uint64_t Default) {
   return toUnsigned(V).value_or(Default);
 }
@@ -244,7 +245,8 @@ inline uint64_t toUnsigned(const Optional<DWARFFormValue> &V,
 /// \param V and optional DWARFFormValue to attempt to extract the value from.
 /// \returns an optional value that contains a value if the form value
 /// was valid and has a reference form.
-inline Optional<uint64_t> toReference(const Optional<DWARFFormValue> &V) {
+inline std::optional<uint64_t>
+toReference(const std::optional<DWARFFormValue> &V) {
   if (V)
     return V->getAsReference();
   return std::nullopt;
@@ -256,7 +258,7 @@ inline Optional<uint64_t> toReference(const Optional<DWARFFormValue> &V) {
 /// \param Default the default value to return in case of failure.
 /// \returns the extracted reference value or Default if the V doesn't have a
 /// value or the form value's encoding wasn't a reference form.
-inline uint64_t toReference(const Optional<DWARFFormValue> &V,
+inline uint64_t toReference(const std::optional<DWARFFormValue> &V,
                             uint64_t Default) {
   return toReference(V).value_or(Default);
 }
@@ -266,7 +268,7 @@ inline uint64_t toReference(const Optional<DWARFFormValue> &V,
 /// \param V and optional DWARFFormValue to attempt to extract the value from.
 /// \returns an optional value that contains a value if the form value
 /// was valid and has a signed constant form.
-inline Optional<int64_t> toSigned(const Optional<DWARFFormValue> &V) {
+inline std::optional<int64_t> toSigned(const std::optional<DWARFFormValue> &V) {
   if (V)
     return V->getAsSignedConstant();
   return std::nullopt;
@@ -278,7 +280,8 @@ inline Optional<int64_t> toSigned(const Optional<DWARFFormValue> &V) {
 /// \param Default the default value to return in case of failure.
 /// \returns the extracted signed integer value or Default if the V doesn't
 /// have a value or the form value's encoding wasn't a signed integer form.
-inline int64_t toSigned(const Optional<DWARFFormValue> &V, int64_t Default) {
+inline int64_t toSigned(const std::optional<DWARFFormValue> &V,
+                        int64_t Default) {
   return toSigned(V).value_or(Default);
 }
 
@@ -287,14 +290,15 @@ inline int64_t toSigned(const Optional<DWARFFormValue> &V, int64_t Default) {
 /// \param V and optional DWARFFormValue to attempt to extract the value from.
 /// \returns an optional value that contains a value if the form value
 /// was valid and has a address form.
-inline Optional<uint64_t> toAddress(const Optional<DWARFFormValue> &V) {
+inline std::optional<uint64_t>
+toAddress(const std::optional<DWARFFormValue> &V) {
   if (V)
     return V->getAsAddress();
   return std::nullopt;
 }
 
-inline Optional<object::SectionedAddress>
-toSectionedAddress(const Optional<DWARFFormValue> &V) {
+inline std::optional<object::SectionedAddress>
+toSectionedAddress(const std::optional<DWARFFormValue> &V) {
   if (V)
     return V->getAsSectionedAddress();
   return std::nullopt;
@@ -306,7 +310,8 @@ toSectionedAddress(const Optional<DWARFFormValue> &V) {
 /// \param Default the default value to return in case of failure.
 /// \returns the extracted address value or Default if the V doesn't have a
 /// value or the form value's encoding wasn't an address form.
-inline uint64_t toAddress(const Optional<DWARFFormValue> &V, uint64_t Default) {
+inline uint64_t toAddress(const std::optional<DWARFFormValue> &V,
+                          uint64_t Default) {
   return toAddress(V).value_or(Default);
 }
 
@@ -315,7 +320,8 @@ inline uint64_t toAddress(const Optional<DWARFFormValue> &V, uint64_t Default) {
 /// \param V and optional DWARFFormValue to attempt to extract the value from.
 /// \returns an optional value that contains a value if the form value
 /// was valid and has a section offset form.
-inline Optional<uint64_t> toSectionOffset(const Optional<DWARFFormValue> &V) {
+inline std::optional<uint64_t>
+toSectionOffset(const std::optional<DWARFFormValue> &V) {
   if (V)
     return V->getAsSectionOffset();
   return std::nullopt;
@@ -327,7 +333,7 @@ inline Optional<uint64_t> toSectionOffset(const Optional<DWARFFormValue> &V) {
 /// \param Default the default value to return in case of failure.
 /// \returns the extracted section offset value or Default if the V doesn't
 /// have a value or the form value's encoding wasn't a section offset form.
-inline uint64_t toSectionOffset(const Optional<DWARFFormValue> &V,
+inline uint64_t toSectionOffset(const std::optional<DWARFFormValue> &V,
                                 uint64_t Default) {
   return toSectionOffset(V).value_or(Default);
 }
@@ -337,7 +343,8 @@ inline uint64_t toSectionOffset(const Optional<DWARFFormValue> &V,
 /// \param V and optional DWARFFormValue to attempt to extract the value from.
 /// \returns an optional value that contains a value if the form value
 /// was valid and has a block form.
-inline Optional<ArrayRef<uint8_t>> toBlock(const Optional<DWARFFormValue> &V) {
+inline std::optional<ArrayRef<uint8_t>>
+toBlock(const std::optional<DWARFFormValue> &V) {
   if (V)
     return V->getAsBlock();
   return std::nullopt;
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFListTable.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFListTable.h
index e5fe14cfb19e..d739d6c195df 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFListTable.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFListTable.h
@@ -112,17 +112,18 @@ public:
 
   void dump(DataExtractor Data, raw_ostream &OS,
             DIDumpOptions DumpOpts = {}) const;
-  Optional<uint64_t> getOffsetEntry(DataExtractor Data, uint32_t Index) const {
+  std::optional<uint64_t> getOffsetEntry(DataExtractor Data,
+                                         uint32_t Index) const {
     if (Index >= HeaderData.OffsetEntryCount)
       return std::nullopt;
 
     return getOffsetEntry(Data, getHeaderOffset() + getHeaderSize(Format), Format, Index);
   }
 
-  static Optional<uint64_t> getOffsetEntry(DataExtractor Data,
-                                           uint64_t OffsetTableOffset,
-                                           dwarf::DwarfFormat Format,
-                                           uint32_t Index) {
+  static std::optional<uint64_t> getOffsetEntry(DataExtractor Data,
+                                                uint64_t OffsetTableOffset,
+                                                dwarf::DwarfFormat Format,
+                                                uint32_t Index) {
     uint8_t OffsetByteSize = Format == dwarf::DWARF64 ? 8 : 4;
     uint64_t Offset = OffsetTableOffset + OffsetByteSize * Index;
     auto R = Data.getUnsigned(&Offset, OffsetByteSize);
@@ -178,13 +179,15 @@ public:
   uint32_t getOffsetEntryCount() const { return Header.getOffsetEntryCount(); }
   dwarf::DwarfFormat getFormat() const { return Header.getFormat(); }
 
-  void dump(DWARFDataExtractor Data, raw_ostream &OS,
-            llvm::function_ref<Optional<object::SectionedAddress>(uint32_t)>
-                LookupPooledAddress,
-            DIDumpOptions DumpOpts = {}) const;
+  void
+  dump(DWARFDataExtractor Data, raw_ostream &OS,
+       llvm::function_ref<std::optional<object::SectionedAddress>(uint32_t)>
+           LookupPooledAddress,
+       DIDumpOptions DumpOpts = {}) const;
 
   /// Return the contents of the offset entry designated by a given index.
-  Optional<uint64_t> getOffsetEntry(DataExtractor Data, uint32_t Index) const {
+  std::optional<uint64_t> getOffsetEntry(DataExtractor Data,
+                                         uint32_t Index) const {
     return Header.getOffsetEntry(Data, Index);
   }
   /// Return the size of the table header including the length but not including
@@ -250,7 +253,7 @@ Error DWARFListType<ListEntryType>::extract(DWARFDataExtractor Data,
 template <typename DWARFListType>
 void DWARFListTableBase<DWARFListType>::dump(
     DWARFDataExtractor Data, raw_ostream &OS,
-    llvm::function_ref<Optional<object::SectionedAddress>(uint32_t)>
+    llvm::function_ref<std::optional<object::SectionedAddress>(uint32_t)>
         LookupPooledAddress,
     DIDumpOptions DumpOpts) const {
   Header.dump(Data, OS, DumpOpts);
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFLocationExpression.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFLocationExpression.h
index 35aa1a78e129..b221f9cc9279 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFLocationExpression.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFLocationExpression.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_DWARF_DWARFLOCATIONEXPRESSION_H
 #define LLVM_DEBUGINFO_DWARF_DWARFLOCATIONEXPRESSION_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/DWARF/DWARFAddressRange.h"
 
 namespace llvm {
@@ -23,7 +22,7 @@ struct DWARFLocationExpression {
   /// The address range in which this expression is valid. None denotes a
   /// default entry which is valid in addresses not covered by other location
   /// expressions, or everywhere if there are no other expressions.
-  Optional<DWARFAddressRange> Range;
+  std::optional<DWARFAddressRange> Range;
 
   /// The expression itself.
   SmallVector<uint8_t, 4> Expr;
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFRelocMap.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFRelocMap.h
index fef59c5e95f8..c5999a65c2a7 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFRelocMap.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFRelocMap.h
@@ -22,7 +22,7 @@ struct RelocAddrEntry {
   uint64_t SectionIndex;
   object::RelocationRef Reloc;
   uint64_t SymbolValue;
-  Optional<object::RelocationRef> Reloc2;
+  std::optional<object::RelocationRef> Reloc2;
   uint64_t SymbolValue2;
   object::RelocationResolver Resolver;
 };
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h
index 25ca5cc42720..584cc5585693 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h
@@ -10,7 +10,6 @@
 #define LLVM_DEBUGINFO_DWARF_DWARFUNIT_H
 
 #include "llvm/ADT/DenseSet.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
@@ -64,7 +63,7 @@ class DWARFUnitHeader {
   uint64_t TypeOffset = 0;
 
   // For v5 split or skeleton compile units only.
-  Optional<uint64_t> DWOId;
+  std::optional<uint64_t> DWOId;
 
   // Unit type as parsed, or derived from the section kind.
   uint8_t UnitType = 0;
@@ -93,7 +92,7 @@ public:
   }
   uint64_t getLength() const { return Length; }
   uint64_t getAbbrOffset() const { return AbbrOffset; }
-  Optional<uint64_t> getDWOId() const { return DWOId; }
+  std::optional<uint64_t> getDWOId() const { return DWOId; }
   void setDWOId(uint64_t Id) {
     assert((!DWOId || *DWOId == Id) && "setting DWOId to a different value");
     DWOId = Id;
@@ -223,17 +222,18 @@ class DWARFUnit {
   const DWARFSection &StringOffsetSection;
   const DWARFSection *AddrOffsetSection;
   DWARFUnit *SU;
-  Optional<uint64_t> AddrOffsetSectionBase;
+  std::optional<uint64_t> AddrOffsetSectionBase;
   bool IsLittleEndian;
   bool IsDWO;
   const DWARFUnitVector &UnitVector;
 
   /// Start, length, and DWARF format of the unit's contribution to the string
   /// offsets table (DWARF v5).
-  Optional<StrOffsetsContributionDescriptor> StringOffsetsTableContribution;
+  std::optional<StrOffsetsContributionDescriptor>
+      StringOffsetsTableContribution;
 
   mutable const DWARFAbbreviationDeclarationSet *Abbrevs;
-  llvm::Optional<object::SectionedAddress> BaseAddr;
+  std::optional<object::SectionedAddress> BaseAddr;
   /// The compile unit debug information entry items.
   std::vector<DWARFDebugInfoEntry> DieArray;
 
@@ -287,14 +287,14 @@ protected:
   /// Find the unit's contribution to the string offsets table and determine its
   /// length and form. The given offset is expected to be derived from the unit
   /// DIE's DW_AT_str_offsets_base attribute.
-  Expected<Optional<StrOffsetsContributionDescriptor>>
+  Expected<std::optional<StrOffsetsContributionDescriptor>>
   determineStringOffsetsTableContribution(DWARFDataExtractor &DA);
 
   /// Find the unit's contribution to the string offsets table and determine its
   /// length and form. The given offset is expected to be 0 in a dwo file or,
   /// in a dwp file, the start of the unit's contribution to the string offsets
   /// table section (as determined by the index table).
-  Expected<Optional<StrOffsetsContributionDescriptor>>
+  Expected<std::optional<StrOffsetsContributionDescriptor>>
   determineStringOffsetsTableContributionDWO(DWARFDataExtractor &DA);
 
 public:
@@ -346,7 +346,7 @@ public:
     AddrOffsetSectionBase = Base;
   }
 
-  Optional<uint64_t> getAddrOffsetSectionBase() const {
+  std::optional<uint64_t> getAddrOffsetSectionBase() const {
     return AddrOffsetSectionBase;
   }
 
@@ -365,7 +365,7 @@ public:
     return LocSectionBase;
   }
 
-  Optional<object::SectionedAddress>
+  std::optional<object::SectionedAddress>
   getAddrOffsetSectionItem(uint32_t Index) const;
   Expected<uint64_t> getStringOffsetSectionItem(uint32_t Index) const;
 
@@ -385,7 +385,7 @@ public:
                          DWARFDebugRangeList &RangeList) const;
   void clear();
 
-  const Optional<StrOffsetsContributionDescriptor> &
+  const std::optional<StrOffsetsContributionDescriptor> &
   getStringOffsetsTableContribution() const {
     return StringOffsetsTableContribution;
   }
@@ -421,7 +421,7 @@ public:
     return false;
   }
 
-  llvm::Optional<object::SectionedAddress> getBaseAddress();
+  std::optional<object::SectionedAddress> getBaseAddress();
 
   DWARFDie getUnitDIE(bool ExtractUnitDIEOnly = true) {
     extractDIEsIfNeeded(ExtractUnitDIEOnly);
@@ -438,7 +438,7 @@ public:
   }
 
   const char *getCompilationDir();
-  Optional<uint64_t> getDWOId() {
+  std::optional<uint64_t> getDWOId() {
     extractDIEsIfNeeded(/*CUDieOnly*/ true);
     return getHeader().getDWOId();
   }
@@ -456,9 +456,9 @@ public:
   /// Return a rangelist's offset based on an index. The index designates
   /// an entry in the rangelist table's offset array and is supplied by
   /// DW_FORM_rnglistx.
-  Optional<uint64_t> getRnglistOffset(uint32_t Index);
+  std::optional<uint64_t> getRnglistOffset(uint32_t Index);
 
-  Optional<uint64_t> getLoclistOffset(uint32_t Index);
+  std::optional<uint64_t> getLoclistOffset(uint32_t Index);
 
   Expected<DWARFAddressRangesVector> collectAddressRanges();
 
@@ -514,7 +514,7 @@ public:
   /// Return the DIE object for a given offset \p Offset inside the
   /// unit's DIE vector.
   DWARFDie getDIEForOffset(uint64_t Offset) {
-    if (Optional<uint32_t> DieIdx = getDIEIndexForOffset(Offset))
+    if (std::optional<uint32_t> DieIdx = getDIEIndexForOffset(Offset))
       return DWARFDie(this, &DieArray[*DieIdx]);
 
     return DWARFDie();
@@ -522,7 +522,7 @@ public:
 
   /// Return the DIE index for a given offset \p Offset inside the
   /// unit's DIE vector.
-  Optional<uint32_t> getDIEIndexForOffset(uint64_t Offset) {
+  std::optional<uint32_t> getDIEIndexForOffset(uint64_t Offset) {
     extractDIEsIfNeeded(false);
     auto It =
         llvm::partition_point(DieArray, [=](const DWARFDebugInfoEntry &DIE) {
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
index 1f1ebe943238..b9ead366cb23 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_DWARF_DWARFVERIFIER_H
 #define LLVM_DEBUGINFO_DWARF_DWARFVERIFIER_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/DIContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
 #include "llvm/DebugInfo/DWARF/DWARFAddressRange.h"
@@ -60,7 +59,7 @@ public:
     /// This is used for finding overlapping ranges in the DW_AT_ranges
     /// attribute of a DIE. It is also used as a set of address ranges that
     /// children address ranges must all be contained in.
-    Optional<DWARFAddressRange> insert(const DWARFAddressRange &R);
+    std::optional<DWARFAddressRange> insert(const DWARFAddressRange &R);
 
     /// Inserts the address range info. If any of its ranges overlaps with a
     /// range in an existing range info, the range info is *not* added and an
diff --git a/llvm/include/llvm/DebugInfo/GSYM/FunctionInfo.h b/llvm/include/llvm/DebugInfo/GSYM/FunctionInfo.h
index d02184ff62ee..713e3c239e95 100644
--- a/llvm/include/llvm/DebugInfo/GSYM/FunctionInfo.h
+++ b/llvm/include/llvm/DebugInfo/GSYM/FunctionInfo.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_GSYM_FUNCTIONINFO_H
 #define LLVM_DEBUGINFO_GSYM_FUNCTIONINFO_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/GSYM/ExtractRanges.h"
 #include "llvm/DebugInfo/GSYM/InlineInfo.h"
 #include "llvm/DebugInfo/GSYM/LineTable.h"
@@ -89,8 +88,8 @@ class GsymReader;
 struct FunctionInfo {
   AddressRange Range;
   uint32_t Name; ///< String table offset in the string table.
-  llvm::Optional<LineTable> OptLineTable;
-  llvm::Optional<InlineInfo> Inline;
+  std::optional<LineTable> OptLineTable;
+  std::optional<InlineInfo> Inline;
 
   FunctionInfo(uint64_t Addr = 0, uint64_t Size = 0, uint32_t N = 0)
       : Range(Addr, Addr + Size), Name(N) {}
diff --git a/llvm/include/llvm/DebugInfo/GSYM/GsymCreator.h b/llvm/include/llvm/DebugInfo/GSYM/GsymCreator.h
index 29ad1c18e295..2eac8b43f006 100644
--- a/llvm/include/llvm/DebugInfo/GSYM/GsymCreator.h
+++ b/llvm/include/llvm/DebugInfo/GSYM/GsymCreator.h
@@ -139,9 +139,9 @@ class GsymCreator {
   DenseMap<llvm::gsym::FileEntry, uint32_t> FileEntryToIndex;
   std::vector<llvm::gsym::FileEntry> Files;
   std::vector<uint8_t> UUID;
-  Optional<AddressRanges> ValidTextRanges;
+  std::optional<AddressRanges> ValidTextRanges;
   AddressRanges Ranges;
-  llvm::Optional<uint64_t> BaseAddress;
+  std::optional<uint64_t> BaseAddress;
   bool Finalized = false;
   bool Quiet;
 
@@ -249,7 +249,7 @@ public:
   }
 
   /// Get the valid text ranges.
-  const Optional<AddressRanges> GetValidTextRanges() const {
+  const std::optional<AddressRanges> GetValidTextRanges() const {
     return ValidTextRanges;
   }
 
diff --git a/llvm/include/llvm/DebugInfo/GSYM/GsymReader.h b/llvm/include/llvm/DebugInfo/GSYM/GsymReader.h
index d026d9b85a58..f2ac33be3bbe 100644
--- a/llvm/include/llvm/DebugInfo/GSYM/GsymReader.h
+++ b/llvm/include/llvm/DebugInfo/GSYM/GsymReader.h
@@ -138,7 +138,7 @@ public:
   /// \param Index An index into the file table.
   /// \returns An optional FileInfo that will be valid if the file index is
   /// valid, or llvm::None if the file index is out of bounds,
-  Optional<FileEntry> getFile(uint32_t Index) const {
+  std::optional<FileEntry> getFile(uint32_t Index) const {
     if (Index < Files.size())
       return Files[Index];
     return std::nullopt;
@@ -191,7 +191,7 @@ public:
   /// \param  OS The output stream to dump to.
   ///
   /// \param FE The object to dump.
-  void dump(raw_ostream &OS, Optional<FileEntry> FE);
+  void dump(raw_ostream &OS, std::optional<FileEntry> FE);
 
   /// Get the number of addresses in this Gsym file.
   uint32_t getNumAddresses() const {
@@ -205,7 +205,7 @@ public:
   /// \param Index A index into the address table.
   /// \returns A resolved virtual address for adddress in the address table
   /// or llvm::None if Index is out of bounds.
-  Optional<uint64_t> getAddress(size_t Index) const;
+  std::optional<uint64_t> getAddress(size_t Index) const;
 
 protected:
 
@@ -237,8 +237,8 @@ protected:
   /// \param Index An index into the AddrOffsets array.
   /// \returns An virtual address that matches the original object file for the
   /// address as the specified index, or llvm::None if Index is out of bounds.
-  template <class T> Optional<uint64_t>
-  addressForIndex(size_t Index) const {
+  template <class T>
+  std::optional<uint64_t> addressForIndex(size_t Index) const {
     ArrayRef<T> AIO = getAddrOffsets<T>();
     if (Index < AIO.size())
       return AIO[Index] + Hdr->BaseAddress;
@@ -254,7 +254,8 @@ protected:
   /// \returns The matching address offset index. This index will be used to
   /// extract the FunctionInfo data's offset from the AddrInfoOffsets array.
   template <class T>
-  llvm::Optional<uint64_t> getAddressOffsetIndex(const uint64_t AddrOffset) const {
+  std::optional<uint64_t>
+  getAddressOffsetIndex(const uint64_t AddrOffset) const {
     ArrayRef<T> AIO = getAddrOffsets<T>();
     const auto Begin = AIO.begin();
     const auto End = AIO.end();
@@ -301,7 +302,7 @@ protected:
   /// \param Index An index into the address table.
   /// \returns An optional GSYM data offset for the offset of the FunctionInfo
   /// that needs to be decoded.
-  Optional<uint64_t> getAddressInfoOffset(size_t Index) const;
+  std::optional<uint64_t> getAddressInfoOffset(size_t Index) const;
 };
 
 } // namespace gsym
diff --git a/llvm/include/llvm/DebugInfo/GSYM/InlineInfo.h b/llvm/include/llvm/DebugInfo/GSYM/InlineInfo.h
index 80385116598a..03bc85396d99 100644
--- a/llvm/include/llvm/DebugInfo/GSYM/InlineInfo.h
+++ b/llvm/include/llvm/DebugInfo/GSYM/InlineInfo.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_GSYM_INLINEINFO_H
 #define LLVM_DEBUGINFO_GSYM_INLINEINFO_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/GSYM/ExtractRanges.h"
 #include "llvm/DebugInfo/GSYM/LineEntry.h"
 #include "llvm/DebugInfo/GSYM/LookupResult.h"
@@ -133,7 +132,7 @@ struct InlineInfo {
   ///
   /// \returns optional vector of InlineInfo objects that describe the
   /// inline call stack for a given address, false otherwise.
-  llvm::Optional<InlineArray> getInlineStack(uint64_t Addr) const;
+  std::optional<InlineArray> getInlineStack(uint64_t Addr) const;
 
   /// Decode an InlineInfo object from a binary data stream.
   ///
diff --git a/llvm/include/llvm/DebugInfo/GSYM/LineTable.h b/llvm/include/llvm/DebugInfo/GSYM/LineTable.h
index c0121a8787be..a27019fc769d 100644
--- a/llvm/include/llvm/DebugInfo/GSYM/LineTable.h
+++ b/llvm/include/llvm/DebugInfo/GSYM/LineTable.h
@@ -170,7 +170,7 @@ public:
   ///
   /// \returns An optional line entry with the first line entry if the line
   /// table isn't empty, or llvm::None if the line table is emtpy.
-  Optional<LineEntry> first() const {
+  std::optional<LineEntry> first() const {
     if (Lines.empty())
       return std::nullopt;
     return Lines.front();
@@ -179,7 +179,7 @@ public:
   ///
   /// \returns An optional line entry with the last line entry if the line
   /// table isn't empty, or llvm::None if the line table is emtpy.
-  Optional<LineEntry> last() const {
+  std::optional<LineEntry> last() const {
     if (Lines.empty())
       return std::nullopt;
     return Lines.back();
diff --git a/llvm/include/llvm/DebugInfo/PDB/DIA/DIADataStream.h b/llvm/include/llvm/DebugInfo/PDB/DIA/DIADataStream.h
index f05b58c55507..d331ba68557a 100644
--- a/llvm/include/llvm/DebugInfo/PDB/DIA/DIADataStream.h
+++ b/llvm/include/llvm/DebugInfo/PDB/DIA/DIADataStream.h
@@ -20,7 +20,7 @@ public:
 
   uint32_t getRecordCount() const override;
   std::string getName() const override;
-  llvm::Optional<RecordType> getItemAtIndex(uint32_t Index) const override;
+  std::optional<RecordType> getItemAtIndex(uint32_t Index) const override;
   bool getNext(RecordType &Record) override;
   void reset() override;
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/IPDBDataStream.h b/llvm/include/llvm/DebugInfo/PDB/IPDBDataStream.h
index 4d0589a87915..fb18396cafe3 100644
--- a/llvm/include/llvm/DebugInfo/PDB/IPDBDataStream.h
+++ b/llvm/include/llvm/DebugInfo/PDB/IPDBDataStream.h
@@ -9,9 +9,9 @@
 #ifndef LLVM_DEBUGINFO_PDB_IPDBDATASTREAM_H
 #define LLVM_DEBUGINFO_PDB_IPDBDATASTREAM_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include <cstdint>
+#include <optional>
 #include <string>
 
 namespace llvm {
@@ -28,7 +28,7 @@ public:
 
   virtual uint32_t getRecordCount() const = 0;
   virtual std::string getName() const = 0;
-  virtual Optional<RecordType> getItemAtIndex(uint32_t Index) const = 0;
+  virtual std::optional<RecordType> getItemAtIndex(uint32_t Index) const = 0;
   virtual bool getNext(RecordType &Record) = 0;
   virtual void reset() = 0;
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/DbiStreamBuilder.h b/llvm/include/llvm/DebugInfo/PDB/Native/DbiStreamBuilder.h
index 2f99aa942a05..9a84fc3e7c55 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/DbiStreamBuilder.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/DbiStreamBuilder.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_PDB_NATIVE_DBISTREAMBUILDER_H
 #define LLVM_DEBUGINFO_PDB_NATIVE_DBISTREAMBUILDER_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/BinaryFormat/COFF.h"
@@ -105,7 +104,7 @@ private:
   msf::MSFBuilder &Msf;
   BumpPtrAllocator &Allocator;
 
-  Optional<PdbRaw_DbiVer> VerHeader;
+  std::optional<PdbRaw_DbiVer> VerHeader;
   uint32_t Age;
   uint16_t BuildNumber;
   uint16_t PdbDllVersion;
@@ -120,7 +119,7 @@ private:
 
   std::vector<std::unique_ptr<DbiModuleDescriptorBuilder>> ModiList;
 
-  Optional<codeview::DebugFrameDataSubsection> NewFpoData;
+  std::optional<codeview::DebugFrameDataSubsection> NewFpoData;
   std::vector<object::FpoData> OldFpoData;
 
   StringMap<uint32_t> SourceFileNames;
@@ -130,7 +129,7 @@ private:
   MutableBinaryByteStream FileInfoBuffer;
   std::vector<SectionContrib> SectionContribs;
   std::vector<SecMapEntry> SectionMap;
-  std::array<Optional<DebugStream>, (int)DbgHeaderType::Max> DbgStreams;
+  std::array<std::optional<DebugStream>, (int)DbgHeaderType::Max> DbgStreams;
 };
 } // namespace pdb
 }
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/HashTable.h b/llvm/include/llvm/DebugInfo/PDB/Native/HashTable.h
index 69fcb4aa9994..eb03397ba694 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/HashTable.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/HashTable.h
@@ -218,7 +218,7 @@ public:
   const_iterator find_as(const Key &K, TraitsT &Traits) const {
     uint32_t H = Traits.hashLookupKey(K) % capacity();
     uint32_t I = H;
-    Optional<uint32_t> FirstUnused;
+    std::optional<uint32_t> FirstUnused;
     do {
       if (isPresent(I)) {
         if (Traits.storageKeyToLookupKey(Buckets[I].first) == K)
@@ -271,7 +271,7 @@ private:
   /// from a real key to an internal key.
   template <typename Key, typename TraitsT>
   bool set_as_internal(const Key &K, ValueT V, TraitsT &Traits,
-                       Optional<uint32_t> InternalKey) {
+                       std::optional<uint32_t> InternalKey) {
     auto Entry = find_as(K, Traits);
     if (Entry != end()) {
       assert(isPresent(Entry.index()));
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/InfoStreamBuilder.h b/llvm/include/llvm/DebugInfo/PDB/Native/InfoStreamBuilder.h
index 2d5088a3bd42..4b77e321353f 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/InfoStreamBuilder.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/InfoStreamBuilder.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_PDB_NATIVE_INFOSTREAMBUILDER_H
 #define LLVM_DEBUGINFO_PDB_NATIVE_INFOSTREAMBUILDER_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/Support/Error.h"
 
 #include "llvm/DebugInfo/CodeView/GUID.h"
@@ -46,7 +45,7 @@ public:
   bool hashPDBContentsToGUID() const { return HashPDBContentsToGUID; }
   uint32_t getAge() const { return Age; }
   codeview::GUID getGuid() const { return Guid; }
-  Optional<uint32_t> getSignature() const { return Signature; }
+  std::optional<uint32_t> getSignature() const { return Signature; }
 
   uint32_t finalize();
 
@@ -61,7 +60,7 @@ private:
   std::vector<PdbRaw_FeatureSig> Features;
   PdbRaw_ImplVer Ver;
   uint32_t Age;
-  Optional<uint32_t> Signature;
+  std::optional<uint32_t> Signature;
   codeview::GUID Guid;
 
   bool HashPDBContentsToGUID = false;
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/InputFile.h b/llvm/include/llvm/DebugInfo/PDB/Native/InputFile.h
index c0d722960540..834cd96b77b4 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/InputFile.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/InputFile.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_PDB_NATIVE_INPUTFILE_H
 #define LLVM_DEBUGINFO_PDB_NATIVE_INPUTFILE_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/PointerUnion.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/iterator.h"
@@ -149,7 +148,7 @@ private:
   bool isEnd() const;
 
   uint32_t Index = 0;
-  Optional<object::section_iterator> SectionIter;
+  std::optional<object::section_iterator> SectionIter;
   SymbolGroup Value;
 };
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/LinePrinter.h b/llvm/include/llvm/DebugInfo/PDB/Native/LinePrinter.h
index 0db21309f593..bb029e534c74 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/LinePrinter.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/LinePrinter.h
@@ -30,10 +30,10 @@ struct FilterOptions {
   std::list<std::string> IncludeCompilands;
   uint32_t PaddingThreshold;
   uint32_t SizeThreshold;
-  llvm::Optional<uint32_t> DumpModi;
-  llvm::Optional<uint32_t> ParentRecurseDepth;
-  llvm::Optional<uint32_t> ChildrenRecurseDepth;
-  llvm::Optional<uint32_t> SymbolOffset;
+  std::optional<uint32_t> DumpModi;
+  std::optional<uint32_t> ParentRecurseDepth;
+  std::optional<uint32_t> ChildrenRecurseDepth;
+  std::optional<uint32_t> SymbolOffset;
   bool JustMyCode;
 };
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypeEnum.h b/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypeEnum.h
index 429c06f29ac7..01f13ce1073e 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypeEnum.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypeEnum.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_PDB_NATIVE_NATIVETYPEENUM_H
 #define LLVM_DEBUGINFO_PDB_NATIVE_NATIVETYPEENUM_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
 #include "llvm/DebugInfo/PDB/IPDBRawSymbol.h"
@@ -65,9 +64,9 @@ public:
 
 protected:
   codeview::TypeIndex Index;
-  Optional<codeview::EnumRecord> Record;
+  std::optional<codeview::EnumRecord> Record;
   NativeTypeEnum *UnmodifiedType = nullptr;
-  Optional<codeview::ModifierRecord> Modifiers;
+  std::optional<codeview::ModifierRecord> Modifiers;
 };
 
 } // namespace pdb
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypePointer.h b/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypePointer.h
index 1f357754ac0f..184e00086849 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypePointer.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypePointer.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_PDB_NATIVE_NATIVETYPEPOINTER_H
 #define LLVM_DEBUGINFO_PDB_NATIVE_NATIVETYPEPOINTER_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
 #include "llvm/DebugInfo/PDB/IPDBRawSymbol.h"
@@ -52,7 +51,7 @@ public:
 protected:
   bool isMemberPointer() const;
   codeview::TypeIndex TI;
-  Optional<codeview::PointerRecord> Record;
+  std::optional<codeview::PointerRecord> Record;
 };
 
 } // namespace pdb
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypeUDT.h b/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypeUDT.h
index a1dd39c0b4be..79924a78cd21 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypeUDT.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/NativeTypeUDT.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_PDB_NATIVE_NATIVETYPEUDT_H
 #define LLVM_DEBUGINFO_PDB_NATIVE_NATIVETYPEUDT_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
 #include "llvm/DebugInfo/PDB/IPDBRawSymbol.h"
@@ -64,11 +63,11 @@ public:
 protected:
   codeview::TypeIndex Index;
 
-  Optional<codeview::ClassRecord> Class;
-  Optional<codeview::UnionRecord> Union;
+  std::optional<codeview::ClassRecord> Class;
+  std::optional<codeview::UnionRecord> Union;
   NativeTypeUDT *UnmodifiedType = nullptr;
   codeview::TagRecord *Tag = nullptr;
-  Optional<codeview::ModifierRecord> Modifiers;
+  std::optional<codeview::ModifierRecord> Modifiers;
 };
 
 } // namespace pdb
diff --git a/llvm/include/llvm/DebugInfo/PDB/Native/TpiStreamBuilder.h b/llvm/include/llvm/DebugInfo/PDB/Native/TpiStreamBuilder.h
index 9f320358144c..855b5fe1f931 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Native/TpiStreamBuilder.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Native/TpiStreamBuilder.h
@@ -9,7 +9,6 @@
 #ifndef LLVM_DEBUGINFO_PDB_NATIVE_TPISTREAMBUILDER_H
 #define LLVM_DEBUGINFO_PDB_NATIVE_TPISTREAMBUILDER_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/CodeView/CVRecord.h"
 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
 #include "llvm/DebugInfo/PDB/Native/RawConstants.h"
@@ -46,7 +45,7 @@ public:
   TpiStreamBuilder &operator=(const TpiStreamBuilder &) = delete;
 
   void setVersionHeader(PdbRaw_TpiVer Version);
-  void addTypeRecord(ArrayRef<uint8_t> Type, Optional<uint32_t> Hash);
+  void addTypeRecord(ArrayRef<uint8_t> Type, std::optional<uint32_t> Hash);
   void addTypeRecords(ArrayRef<uint8_t> Types, ArrayRef<uint16_t> Sizes,
                       ArrayRef<uint32_t> Hashes);
 
diff --git a/llvm/include/llvm/DebugInfo/Symbolize/DIPrinter.h b/llvm/include/llvm/DebugInfo/Symbolize/DIPrinter.h
index 91748e15ba65..f799b0a4cde0 100644
--- a/llvm/include/llvm/DebugInfo/Symbolize/DIPrinter.h
+++ b/llvm/include/llvm/DebugInfo/Symbolize/DIPrinter.h
@@ -14,7 +14,6 @@
 #ifndef LLVM_DEBUGINFO_SYMBOLIZE_DIPRINTER_H
 #define LLVM_DEBUGINFO_SYMBOLIZE_DIPRINTER_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/JSON.h"
 #include <memory>
@@ -34,7 +33,7 @@ class SourceCode;
 
 struct Request {
   StringRef ModuleName;
-  Optional<uint64_t> Address;
+  std::optional<uint64_t> Address;
 };
 
 class DIPrinter {
diff --git a/llvm/include/llvm/DebugInfo/Symbolize/Markup.h b/llvm/include/llvm/DebugInfo/Symbolize/Markup.h
index 0061d5997693..c6242267f1e2 100644
--- a/llvm/include/llvm/DebugInfo/Symbolize/Markup.h
+++ b/llvm/include/llvm/DebugInfo/Symbolize/Markup.h
@@ -16,7 +16,6 @@
 #ifndef LLVM_DEBUGINFO_SYMBOLIZE_MARKUP_H
 #define LLVM_DEBUGINFO_SYMBOLIZE_MARKUP_H
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/StringSet.h"
@@ -80,17 +79,17 @@ public:
   /// previous call.
   ///
   /// \returns the next markup node or None if none remain.
-  Optional<MarkupNode> nextNode();
+  std::optional<MarkupNode> nextNode();
 
   bool isSGR(const MarkupNode &Node) const {
     return SGRSyntax.match(Node.Text);
   }
 
 private:
-  Optional<MarkupNode> parseElement(StringRef Line);
+  std::optional<MarkupNode> parseElement(StringRef Line);
   void parseTextOutsideMarkup(StringRef Text);
-  Optional<StringRef> parseMultiLineBegin(StringRef Line);
-  Optional<StringRef> parseMultiLineEnd(StringRef Line);
+  std::optional<StringRef> parseMultiLineBegin(StringRef Line);
+  std::optional<StringRef> parseMultiLineEnd(StringRef Line);
 
   // Tags of elements that can span multiple lines.
   const StringSet<> MultilineTags;
diff --git a/llvm/include/llvm/DebugInfo/Symbolize/MarkupFilter.h b/llvm/include/llvm/DebugInfo/Symbolize/MarkupFilter.h
index 27c07f7942c7..534255640075 100644
--- a/llvm/include/llvm/DebugInfo/Symbolize/MarkupFilter.h
+++ b/llvm/include/llvm/DebugInfo/Symbolize/MarkupFilter.h
@@ -33,7 +33,7 @@ class LLVMSymbolizer;
 class MarkupFilter {
 public:
   MarkupFilter(raw_ostream &OS, LLVMSymbolizer &Symbolizer,
-               Optional<bool> ColorsEnabled = std::nullopt);
+               std::optional<bool> ColorsEnabled = std::nullopt);
 
   /// Filters a line containing symbolizer markup and writes the human-readable
   /// results to the output stream.
@@ -110,16 +110,16 @@ private:
   void printRawElement(const MarkupNode &Element);
   void printValue(Twine Value);
 
-  Optional<Module> parseModule(const MarkupNode &Element) const;
-  Optional<MMap> parseMMap(const MarkupNode &Element) const;
+  std::optional<Module> parseModule(const MarkupNode &Element) const;
+  std::optional<MMap> parseMMap(const MarkupNode &Element) const;
 
-  Optional<uint64_t> parseAddr(StringRef Str) const;
-  Optional<uint64_t> parseModuleID(StringRef Str) const;
-  Optional<uint64_t> parseSize(StringRef Str) const;
-  Optional<SmallVector<uint8_t>> parseBuildID(StringRef Str) const;
-  Optional<std::string> parseMode(StringRef Str) const;
-  Optional<PCType> parsePCType(StringRef Str) const;
-  Optional<uint64_t> parseFrameNumber(StringRef Str) const;
+  std::optional<uint64_t> parseAddr(StringRef Str) const;
+  std::optional<uint64_t> parseModuleID(StringRef Str) const;
+  std::optional<uint64_t> parseSize(StringRef Str) const;
+  std::optional<SmallVector<uint8_t>> parseBuildID(StringRef Str) const;
+  std::optional<std::string> parseMode(StringRef Str) const;
+  std::optional<PCType> parsePCType(StringRef Str) const;
+  std::optional<uint64_t> parseFrameNumber(StringRef Str) const;
 
   bool checkTag(const MarkupNode &Node) const;
   bool checkNumFields(const MarkupNode &Element, size_t Size) const;
@@ -147,10 +147,10 @@ private:
 
   // A module info line currently being built. This incorporates as much mmap
   // information as possible before being emitted.
-  Optional<ModuleInfoLine> MIL;
+  std::optional<ModuleInfoLine> MIL;
 
   // SGR state.
-  Optional<raw_ostream::Colors> Color;
+  std::optional<raw_ostream::Colors> Color;
   bool Bold = false;
 
   // Map from Module ID to Module.
diff --git a/llvm/lib/BinaryFormat/Dwarf.cpp b/llvm/lib/BinaryFormat/Dwarf.cpp
index f6ea91a7b591..a9bbe41125b1 100644
--- a/llvm/lib/BinaryFormat/Dwarf.cpp
+++ b/llvm/lib/BinaryFormat/Dwarf.cpp
@@ -365,7 +365,8 @@ unsigned llvm::dwarf::LanguageVendor(dwarf::SourceLanguage Lang) {
   }
 }
 
-Optional<unsigned> llvm::dwarf::LanguageLowerBound(dwarf::SourceLanguage Lang) {
+std::optional<unsigned>
+llvm::dwarf::LanguageLowerBound(dwarf::SourceLanguage Lang) {
   switch (Lang) {
   default:
     return std::nullopt;
@@ -691,8 +692,8 @@ StringRef llvm::dwarf::IndexString(unsigned Idx) {
   }
 }
 
-Optional<uint8_t> llvm::dwarf::getFixedFormByteSize(dwarf::Form Form,
-                                                    FormParams Params) {
+std::optional<uint8_t> llvm::dwarf::getFixedFormByteSize(dwarf::Form Form,
+                                                         FormParams Params) {
   switch (Form) {
   case DW_FORM_addr:
     if (Params)
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index b9e44d023294..a3777438bba3 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -730,7 +730,7 @@ void CodeViewDebug::emitTypeInformation() {
   TypeRecordMapping typeMapping(CVMCOS);
   Pipeline.addCallbackToPipeline(typeMapping);
 
-  Optional<TypeIndex> B = Table.getFirst();
+  std::optional<TypeIndex> B = Table.getFirst();
   while (B) {
     // This will fail if the record data is invalid.
     CVType Record = Table.getType(*B);
diff --git a/llvm/lib/CodeGen/AsmPrinter/DIE.cpp b/llvm/lib/CodeGen/AsmPrinter/DIE.cpp
index 617ddbd66e4e..f324eada6a07 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DIE.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DIE.cpp
@@ -425,7 +425,7 @@ void DIEInteger::emitValue(const AsmPrinter *Asm, dwarf::Form Form) const {
 ///
 unsigned DIEInteger::sizeOf(const dwarf::FormParams &FormParams,
                             dwarf::Form Form) const {
-  if (Optional<uint8_t> FixedSize =
+  if (std::optional<uint8_t> FixedSize =
           dwarf::getFixedFormByteSize(Form, FormParams))
     return *FixedSize;
 
diff --git a/llvm/lib/DWARFLinker/DWARFLinker.cpp b/llvm/lib/DWARFLinker/DWARFLinker.cpp
index e067828ed079..b559f14fdc56 100644
--- a/llvm/lib/DWARFLinker/DWARFLinker.cpp
+++ b/llvm/lib/DWARFLinker/DWARFLinker.cpp
@@ -225,7 +225,8 @@ static void analyzeImportedModule(
     SysRoot = CU.getSysRoot();
   if (!SysRoot.empty() && Path.startswith(SysRoot))
     return;
-  Optional<const char*> Name = dwarf::toString(DIE.find(dwarf::DW_AT_name));
+  std::optional<const char *> Name =
+      dwarf::toString(DIE.find(dwarf::DW_AT_name));
   if (!Name)
     return;
   auto &Entry = (*ParseableSwiftInterfaces)[*Name];
@@ -498,7 +499,7 @@ unsigned DWARFLinker::shouldKeepSubprogramDIE(
 
   Flags |= TF_Keep;
 
-  Optional<uint64_t> HighPc = DIE.getHighPC(*LowPc);
+  std::optional<uint64_t> HighPc = DIE.getHighPC(*LowPc);
   if (!HighPc) {
     reportWarning("Function without high_pc. Range will be discarded.\n", File,
                   &DIE);
@@ -882,7 +883,7 @@ void DWARFLinker::assignAbbrev(DIEAbbrev &Abbrev) {
 unsigned DWARFLinker::DIECloner::cloneStringAttribute(
     DIE &Die, AttributeSpec AttrSpec, const DWARFFormValue &Val,
     const DWARFUnit &, OffsetsStringPool &StringPool, AttributesInfo &Info) {
-  Optional<const char *> String = dwarf::toString(Val);
+  std::optional<const char *> String = dwarf::toString(Val);
   if (!String)
     return 0;
 
@@ -1107,7 +1108,7 @@ unsigned DWARFLinker::DIECloner::cloneAddressAttribute(
   dwarf::Form Form = AttrSpec.Form;
   uint64_t Addr = 0;
   if (Form == dwarf::DW_FORM_addrx) {
-    if (Optional<uint64_t> AddrOffsetSectionBase =
+    if (std::optional<uint64_t> AddrOffsetSectionBase =
             Unit.getOrigUnit().getAddrOffsetSectionBase()) {
       uint64_t StartOffset =
           *AddrOffsetSectionBase +
@@ -1943,7 +1944,7 @@ uint32_t DWARFLinker::DIECloner::hashFullyQualifiedName(DWARFDie DIE,
   const char *Name = nullptr;
   DWARFUnit *OrigUnit = &U.getOrigUnit();
   CompileUnit *CU = &U;
-  Optional<DWARFFormValue> Ref;
+  std::optional<DWARFFormValue> Ref;
 
   while (true) {
     if (const char *CurrentName = DIE.getName(DINameKind::ShortName))
diff --git a/llvm/lib/DWARFLinker/DWARFLinkerCompileUnit.cpp b/llvm/lib/DWARFLinker/DWARFLinkerCompileUnit.cpp
index 1cb20c0bb948..77d914aec79a 100644
--- a/llvm/lib/DWARFLinker/DWARFLinkerCompileUnit.cpp
+++ b/llvm/lib/DWARFLinker/DWARFLinkerCompileUnit.cpp
@@ -52,7 +52,7 @@ void CompileUnit::markEverythingAsKept() {
         DIE.getTag() != dwarf::DW_TAG_constant)
       continue;
 
-    Optional<DWARFFormValue> Value;
+    std::optional<DWARFFormValue> Value;
     if (!(Value = DIE.find(dwarf::DW_AT_location))) {
       if ((Value = DIE.find(dwarf::DW_AT_const_value)) &&
           !inFunctionScope(*this, I.ParentIdx))
diff --git a/llvm/lib/DebugInfo/CodeView/AppendingTypeTableBuilder.cpp b/llvm/lib/DebugInfo/CodeView/AppendingTypeTableBuilder.cpp
index f0ffb41142f6..dc32e8336927 100644
--- a/llvm/lib/DebugInfo/CodeView/AppendingTypeTableBuilder.cpp
+++ b/llvm/lib/DebugInfo/CodeView/AppendingTypeTableBuilder.cpp
@@ -29,14 +29,14 @@ AppendingTypeTableBuilder::AppendingTypeTableBuilder(BumpPtrAllocator &Storage)
 
 AppendingTypeTableBuilder::~AppendingTypeTableBuilder() = default;
 
-Optional<TypeIndex> AppendingTypeTableBuilder::getFirst() {
+std::optional<TypeIndex> AppendingTypeTableBuilder::getFirst() {
   if (empty())
     return std::nullopt;
 
   return TypeIndex(TypeIndex::FirstNonSimpleIndex);
 }
 
-Optional<TypeIndex> AppendingTypeTableBuilder::getNext(TypeIndex Prev) {
+std::optional<TypeIndex> AppendingTypeTableBuilder::getNext(TypeIndex Prev) {
   if (++Prev == nextTypeIndex())
     return std::nullopt;
   return Prev;
diff --git a/llvm/lib/DebugInfo/CodeView/CVTypeVisitor.cpp b/llvm/lib/DebugInfo/CodeView/CVTypeVisitor.cpp
index 5da300f710d5..689c643a7006 100644
--- a/llvm/lib/DebugInfo/CodeView/CVTypeVisitor.cpp
+++ b/llvm/lib/DebugInfo/CodeView/CVTypeVisitor.cpp
@@ -157,7 +157,7 @@ Error CVTypeVisitor::visitTypeStream(CVTypeRange Types) {
 }
 
 Error CVTypeVisitor::visitTypeStream(TypeCollection &Types) {
-  Optional<TypeIndex> I = Types.getFirst();
+  std::optional<TypeIndex> I = Types.getFirst();
   while (I) {
     CVType Type = Types.getType(*I);
     if (auto EC = visitTypeRecord(Type, *I))
diff --git a/llvm/lib/DebugInfo/CodeView/CodeViewRecordIO.cpp b/llvm/lib/DebugInfo/CodeView/CodeViewRecordIO.cpp
index a66f9af98835..55fafa8472d7 100644
--- a/llvm/lib/DebugInfo/CodeView/CodeViewRecordIO.cpp
+++ b/llvm/lib/DebugInfo/CodeView/CodeViewRecordIO.cpp
@@ -17,7 +17,7 @@
 using namespace llvm;
 using namespace llvm::codeview;
 
-Error CodeViewRecordIO::beginRecord(Optional<uint32_t> MaxLength) {
+Error CodeViewRecordIO::beginRecord(std::optional<uint32_t> MaxLength) {
   RecordLimit Limit;
   Limit.MaxLength = MaxLength;
   Limit.BeginOffset = getCurrentOffset();
@@ -67,9 +67,9 @@ uint32_t CodeViewRecordIO::maxFieldLength() const {
   // ever be at most 1 sub-record deep (in a FieldList), but this works for
   // the general case.
   uint32_t Offset = getCurrentOffset();
-  Optional<uint32_t> Min = Limits.front().bytesRemaining(Offset);
+  std::optional<uint32_t> Min = Limits.front().bytesRemaining(Offset);
   for (auto X : makeArrayRef(Limits).drop_front()) {
-    Optional<uint32_t> ThisMin = X.bytesRemaining(Offset);
+    std::optional<uint32_t> ThisMin = X.bytesRemaining(Offset);
     if (ThisMin)
       Min = Min ? std::min(*Min, *ThisMin) : *ThisMin;
   }
diff --git a/llvm/lib/DebugInfo/CodeView/ContinuationRecordBuilder.cpp b/llvm/lib/DebugInfo/CodeView/ContinuationRecordBuilder.cpp
index a3dbb3954d5c..fa59e7f9dba1 100644
--- a/llvm/lib/DebugInfo/CodeView/ContinuationRecordBuilder.cpp
+++ b/llvm/lib/DebugInfo/CodeView/ContinuationRecordBuilder.cpp
@@ -147,7 +147,7 @@ void ContinuationRecordBuilder::insertSegmentEnd(uint32_t Offset) {
 }
 
 CVType ContinuationRecordBuilder::createSegmentRecord(
-    uint32_t OffBegin, uint32_t OffEnd, Optional<TypeIndex> RefersTo) {
+    uint32_t OffBegin, uint32_t OffEnd, std::optional<TypeIndex> RefersTo) {
   assert(OffEnd - OffBegin <= USHRT_MAX);
 
   MutableArrayRef<uint8_t> Data = Buffer.data();
@@ -228,7 +228,7 @@ std::vector<CVType> ContinuationRecordBuilder::end(TypeIndex Index) {
 
   uint32_t End = SegmentWriter.getOffset();
 
-  Optional<TypeIndex> RefersTo;
+  std::optional<TypeIndex> RefersTo;
   for (uint32_t Offset : reverse(SO)) {
     Types.push_back(createSegmentRecord(Offset, End, RefersTo));
 
diff --git a/llvm/lib/DebugInfo/CodeView/GlobalTypeTableBuilder.cpp b/llvm/lib/DebugInfo/CodeView/GlobalTypeTableBuilder.cpp
index 24e8b583201b..1428d3038e77 100644
--- a/llvm/lib/DebugInfo/CodeView/GlobalTypeTableBuilder.cpp
+++ b/llvm/lib/DebugInfo/CodeView/GlobalTypeTableBuilder.cpp
@@ -32,14 +32,14 @@ GlobalTypeTableBuilder::GlobalTypeTableBuilder(BumpPtrAllocator &Storage)
 
 GlobalTypeTableBuilder::~GlobalTypeTableBuilder() = default;
 
-Optional<TypeIndex> GlobalTypeTableBuilder::getFirst() {
+std::optional<TypeIndex> GlobalTypeTableBuilder::getFirst() {
   if (empty())
     return std::nullopt;
 
   return TypeIndex(TypeIndex::FirstNonSimpleIndex);
 }
 
-Optional<TypeIndex> GlobalTypeTableBuilder::getNext(TypeIndex Prev) {
+std::optional<TypeIndex> GlobalTypeTableBuilder::getNext(TypeIndex Prev) {
   if (++Prev == nextTypeIndex())
     return std::nullopt;
   return Prev;
diff --git a/llvm/lib/DebugInfo/CodeView/LazyRandomTypeCollection.cpp b/llvm/lib/DebugInfo/CodeView/LazyRandomTypeCollection.cpp
index 5e6a2e05d937..28771bd805fc 100644
--- a/llvm/lib/DebugInfo/CodeView/LazyRandomTypeCollection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/LazyRandomTypeCollection.cpp
@@ -98,7 +98,7 @@ CVType LazyRandomTypeCollection::getType(TypeIndex Index) {
   return Records[Index.toArrayIndex()].Type;
 }
 
-Optional<CVType> LazyRandomTypeCollection::tryGetType(TypeIndex Index) {
+std::optional<CVType> LazyRandomTypeCollection::tryGetType(TypeIndex Index) {
   if (Index.isSimple())
     return std::nullopt;
 
@@ -202,7 +202,7 @@ Error LazyRandomTypeCollection::visitRangeForType(TypeIndex TI) {
   return Error::success();
 }
 
-Optional<TypeIndex> LazyRandomTypeCollection::getFirst() {
+std::optional<TypeIndex> LazyRandomTypeCollection::getFirst() {
   TypeIndex TI = TypeIndex::fromArrayIndex(0);
   if (auto EC = ensureTypeExists(TI)) {
     consumeError(std::move(EC));
@@ -211,7 +211,7 @@ Optional<TypeIndex> LazyRandomTypeCollection::getFirst() {
   return TI;
 }
 
-Optional<TypeIndex> LazyRandomTypeCollection::getNext(TypeIndex Prev) {
+std::optional<TypeIndex> LazyRandomTypeCollection::getNext(TypeIndex Prev) {
   // We can't be sure how long this type stream is, given that the initial count
   // given to the constructor is just a hint.  So just try to make sure the next
   // record exists, and if anything goes wrong, we must be at the end.
diff --git a/llvm/lib/DebugInfo/CodeView/MergingTypeTableBuilder.cpp b/llvm/lib/DebugInfo/CodeView/MergingTypeTableBuilder.cpp
index 70a1878d13b1..24fe29192809 100644
--- a/llvm/lib/DebugInfo/CodeView/MergingTypeTableBuilder.cpp
+++ b/llvm/lib/DebugInfo/CodeView/MergingTypeTableBuilder.cpp
@@ -33,14 +33,14 @@ MergingTypeTableBuilder::MergingTypeTableBuilder(BumpPtrAllocator &Storage)
 
 MergingTypeTableBuilder::~MergingTypeTableBuilder() = default;
 
-Optional<TypeIndex> MergingTypeTableBuilder::getFirst() {
+std::optional<TypeIndex> MergingTypeTableBuilder::getFirst() {
   if (empty())
     return std::nullopt;
 
   return TypeIndex(TypeIndex::FirstNonSimpleIndex);
 }
 
-Optional<TypeIndex> MergingTypeTableBuilder::getNext(TypeIndex Prev) {
+std::optional<TypeIndex> MergingTypeTableBuilder::getNext(TypeIndex Prev) {
   if (++Prev == nextTypeIndex())
     return std::nullopt;
   return Prev;
diff --git a/llvm/lib/DebugInfo/CodeView/TypeRecordMapping.cpp b/llvm/lib/DebugInfo/CodeView/TypeRecordMapping.cpp
index 7f4511258c64..876def851e29 100644
--- a/llvm/lib/DebugInfo/CodeView/TypeRecordMapping.cpp
+++ b/llvm/lib/DebugInfo/CodeView/TypeRecordMapping.cpp
@@ -236,7 +236,7 @@ Error TypeRecordMapping::visitTypeBegin(CVType &CVR) {
   // FieldList and MethodList records can be any length because they can be
   // split with continuation records.  All other record types cannot be
   // longer than the maximum record length.
-  Optional<uint32_t> MaxLen;
+  std::optional<uint32_t> MaxLen;
   if (CVR.kind() != TypeLeafKind::LF_FIELDLIST &&
       CVR.kind() != TypeLeafKind::LF_METHODLIST)
     MaxLen = MaxRecordLength - sizeof(RecordPrefix);
diff --git a/llvm/lib/DebugInfo/CodeView/TypeStreamMerger.cpp b/llvm/lib/DebugInfo/CodeView/TypeStreamMerger.cpp
index fdc649439682..37b1c001c0bd 100644
--- a/llvm/lib/DebugInfo/CodeView/TypeStreamMerger.cpp
+++ b/llvm/lib/DebugInfo/CodeView/TypeStreamMerger.cpp
@@ -79,7 +79,7 @@ public:
   Error mergeTypesAndIds(MergingTypeTableBuilder &DestIds,
                          MergingTypeTableBuilder &DestTypes,
                          const CVTypeArray &IdsAndTypes,
-                         Optional<PCHMergerInfo> &PCHInfo);
+                         std::optional<PCHMergerInfo> &PCHInfo);
   Error mergeIdRecords(MergingTypeTableBuilder &Dest,
                        ArrayRef<TypeIndex> TypeSourceToDest,
                        const CVTypeArray &Ids);
@@ -91,14 +91,14 @@ public:
                          GlobalTypeTableBuilder &DestTypes,
                          const CVTypeArray &IdsAndTypes,
                          ArrayRef<GloballyHashedType> Hashes,
-                         Optional<PCHMergerInfo> &PCHInfo);
+                         std::optional<PCHMergerInfo> &PCHInfo);
   Error mergeIdRecords(GlobalTypeTableBuilder &Dest,
                        ArrayRef<TypeIndex> TypeSourceToDest,
                        const CVTypeArray &Ids,
                        ArrayRef<GloballyHashedType> Hashes);
   Error mergeTypeRecords(GlobalTypeTableBuilder &Dest, const CVTypeArray &Types,
                          ArrayRef<GloballyHashedType> Hashes,
-                         Optional<PCHMergerInfo> &PCHInfo);
+                         std::optional<PCHMergerInfo> &PCHInfo);
 
 private:
   Error doit(const CVTypeArray &Types);
@@ -198,7 +198,7 @@ private:
   /// its type indices.
   SmallVector<uint8_t, 256> RemapStorage;
 
-  Optional<PCHMergerInfo> PCHInfo;
+  std::optional<PCHMergerInfo> PCHInfo;
 };
 
 } // end anonymous namespace
@@ -258,10 +258,9 @@ Error TypeStreamMerger::mergeIdRecords(MergingTypeTableBuilder &Dest,
   return doit(Ids);
 }
 
-Error TypeStreamMerger::mergeTypesAndIds(MergingTypeTableBuilder &DestIds,
-                                         MergingTypeTableBuilder &DestTypes,
-                                         const CVTypeArray &IdsAndTypes,
-                                         Optional<PCHMergerInfo> &PCHInfo) {
+Error TypeStreamMerger::mergeTypesAndIds(
+    MergingTypeTableBuilder &DestIds, MergingTypeTableBuilder &DestTypes,
+    const CVTypeArray &IdsAndTypes, std::optional<PCHMergerInfo> &PCHInfo) {
   DestIdStream = &DestIds;
   DestTypeStream = &DestTypes;
   UseGlobalHashes = false;
@@ -271,10 +270,10 @@ Error TypeStreamMerger::mergeTypesAndIds(MergingTypeTableBuilder &DestIds,
 }
 
 // Global hashing entry points
-Error TypeStreamMerger::mergeTypeRecords(GlobalTypeTableBuilder &Dest,
-                                         const CVTypeArray &Types,
-                                         ArrayRef<GloballyHashedType> Hashes,
-                                         Optional<PCHMergerInfo> &PCHInfo) {
+Error TypeStreamMerger::mergeTypeRecords(
+    GlobalTypeTableBuilder &Dest, const CVTypeArray &Types,
+    ArrayRef<GloballyHashedType> Hashes,
+    std::optional<PCHMergerInfo> &PCHInfo) {
   DestGlobalTypeStream = &Dest;
   UseGlobalHashes = true;
   GlobalHashes = Hashes;
@@ -295,11 +294,10 @@ Error TypeStreamMerger::mergeIdRecords(GlobalTypeTableBuilder &Dest,
   return doit(Ids);
 }
 
-Error TypeStreamMerger::mergeTypesAndIds(GlobalTypeTableBuilder &DestIds,
-                                         GlobalTypeTableBuilder &DestTypes,
-                                         const CVTypeArray &IdsAndTypes,
-                                         ArrayRef<GloballyHashedType> Hashes,
-                                         Optional<PCHMergerInfo> &PCHInfo) {
+Error TypeStreamMerger::mergeTypesAndIds(
+    GlobalTypeTableBuilder &DestIds, GlobalTypeTableBuilder &DestTypes,
+    const CVTypeArray &IdsAndTypes, ArrayRef<GloballyHashedType> Hashes,
+    std::optional<PCHMergerInfo> &PCHInfo) {
   DestGlobalIdStream = &DestIds;
   DestGlobalTypeStream = &DestTypes;
   UseGlobalHashes = true;
@@ -448,7 +446,7 @@ Error llvm::codeview::mergeIdRecords(MergingTypeTableBuilder &Dest,
 Error llvm::codeview::mergeTypeAndIdRecords(
     MergingTypeTableBuilder &DestIds, MergingTypeTableBuilder &DestTypes,
     SmallVectorImpl<TypeIndex> &SourceToDest, const CVTypeArray &IdsAndTypes,
-    Optional<PCHMergerInfo> &PCHInfo) {
+    std::optional<PCHMergerInfo> &PCHInfo) {
   TypeStreamMerger M(SourceToDest);
   return M.mergeTypesAndIds(DestIds, DestTypes, IdsAndTypes, PCHInfo);
 }
@@ -456,7 +454,8 @@ Error llvm::codeview::mergeTypeAndIdRecords(
 Error llvm::codeview::mergeTypeAndIdRecords(
     GlobalTypeTableBuilder &DestIds, GlobalTypeTableBuilder &DestTypes,
     SmallVectorImpl<TypeIndex> &SourceToDest, const CVTypeArray &IdsAndTypes,
-    ArrayRef<GloballyHashedType> Hashes, Optional<PCHMergerInfo> &PCHInfo) {
+    ArrayRef<GloballyHashedType> Hashes,
+    std::optional<PCHMergerInfo> &PCHInfo) {
   TypeStreamMerger M(SourceToDest);
   return M.mergeTypesAndIds(DestIds, DestTypes, IdsAndTypes, Hashes, PCHInfo);
 }
@@ -465,7 +464,7 @@ Error llvm::codeview::mergeTypeRecords(GlobalTypeTableBuilder &Dest,
                                        SmallVectorImpl<TypeIndex> &SourceToDest,
                                        const CVTypeArray &Types,
                                        ArrayRef<GloballyHashedType> Hashes,
-                                       Optional<PCHMergerInfo> &PCHInfo) {
+                                       std::optional<PCHMergerInfo> &PCHInfo) {
   TypeStreamMerger M(SourceToDest);
   return M.mergeTypeRecords(Dest, Types, Hashes, PCHInfo);
 }
diff --git a/llvm/lib/DebugInfo/CodeView/TypeTableCollection.cpp b/llvm/lib/DebugInfo/CodeView/TypeTableCollection.cpp
index 4cd19add0616..50ac6fc5906d 100644
--- a/llvm/lib/DebugInfo/CodeView/TypeTableCollection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/TypeTableCollection.cpp
@@ -21,13 +21,13 @@ TypeTableCollection::TypeTableCollection(ArrayRef<ArrayRef<uint8_t>> Records)
   Names.resize(Records.size());
 }
 
-Optional<TypeIndex> TypeTableCollection::getFirst() {
+std::optional<TypeIndex> TypeTableCollection::getFirst() {
   if (empty())
     return std::nullopt;
   return TypeIndex::fromArrayIndex(0);
 }
 
-Optional<TypeIndex> TypeTableCollection::getNext(TypeIndex Prev) {
+std::optional<TypeIndex> TypeTableCollection::getNext(TypeIndex Prev) {
   assert(contains(Prev));
   ++Prev;
   if (Prev.toArrayIndex() == size())
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFAbbreviationDeclaration.cpp b/llvm/lib/DebugInfo/DWARF/DWARFAbbreviationDeclaration.cpp
index fb2aa7b61983..2b5995cb7f53 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFAbbreviationDeclaration.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFAbbreviationDeclaration.cpp
@@ -69,7 +69,7 @@ DWARFAbbreviationDeclaration::extract(DataExtractor Data,
         AttributeSpecs.push_back(AttributeSpec(A, F, V));
         continue;
       }
-      Optional<uint8_t> ByteSize;
+      std::optional<uint8_t> ByteSize;
       // If this abbrevation still has a fixed byte size, then update the
       // FixedAttributeSize as needed.
       switch (F) {
@@ -138,7 +138,7 @@ void DWARFAbbreviationDeclaration::dump(raw_ostream &OS) const {
   OS << '\n';
 }
 
-Optional<uint32_t>
+std::optional<uint32_t>
 DWARFAbbreviationDeclaration::findAttributeIndex(dwarf::Attribute Attr) const {
   for (uint32_t i = 0, e = AttributeSpecs.size(); i != e; ++i) {
     if (AttributeSpecs[i].Attr == Attr)
@@ -164,7 +164,7 @@ uint64_t DWARFAbbreviationDeclaration::getAttributeOffsetFromIndex(
   return Offset;
 }
 
-Optional<DWARFFormValue>
+std::optional<DWARFFormValue>
 DWARFAbbreviationDeclaration::getAttributeValueFromOffset(
     uint32_t AttrIndex, uint64_t Offset, const DWARFUnit &U) const {
   assert(AttributeSpecs.size() > AttrIndex &&
@@ -183,13 +183,13 @@ DWARFAbbreviationDeclaration::getAttributeValueFromOffset(
   return std::nullopt;
 }
 
-Optional<DWARFFormValue>
+std::optional<DWARFFormValue>
 DWARFAbbreviationDeclaration::getAttributeValue(const uint64_t DIEOffset,
                                                 const dwarf::Attribute Attr,
                                                 const DWARFUnit &U) const {
   // Check if this abbreviation has this attribute without needing to skip
   // any data so we can return quickly if it doesn't.
-  Optional<uint32_t> MatchAttrIndex = findAttributeIndex(Attr);
+  std::optional<uint32_t> MatchAttrIndex = findAttributeIndex(Attr);
   if (!MatchAttrIndex)
     return std::nullopt;
 
@@ -210,20 +210,20 @@ size_t DWARFAbbreviationDeclaration::FixedSizeInfo::getByteSize(
   return ByteSize;
 }
 
-Optional<int64_t> DWARFAbbreviationDeclaration::AttributeSpec::getByteSize(
+std::optional<int64_t> DWARFAbbreviationDeclaration::AttributeSpec::getByteSize(
     const DWARFUnit &U) const {
   if (isImplicitConst())
     return 0;
   if (ByteSize.HasByteSize)
     return ByteSize.ByteSize;
-  Optional<int64_t> S;
+  std::optional<int64_t> S;
   auto FixedByteSize = dwarf::getFixedFormByteSize(Form, U.getFormParams());
   if (FixedByteSize)
     S = *FixedByteSize;
   return S;
 }
 
-Optional<size_t> DWARFAbbreviationDeclaration::getFixedAttributesByteSize(
+std::optional<size_t> DWARFAbbreviationDeclaration::getFixedAttributesByteSize(
     const DWARFUnit &U) const {
   if (FixedAttributeSize)
     return FixedAttributeSize->getByteSize(U);
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp b/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
index 0e85160b5737..889d3f0915b0 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp
@@ -143,8 +143,8 @@ void AppleAcceleratorTable::Header::dump(ScopedPrinter &W) const {
   W.printNumber("HeaderData length", HeaderDataLength);
 }
 
-Optional<uint64_t> AppleAcceleratorTable::HeaderData::extractOffset(
-    Optional<DWARFFormValue> Value) const {
+std::optional<uint64_t> AppleAcceleratorTable::HeaderData::extractOffset(
+    std::optional<DWARFFormValue> Value) const {
   if (!Value)
     return std::nullopt;
 
@@ -185,7 +185,7 @@ bool AppleAcceleratorTable::dumpName(ScopedPrinter &W,
       W.startLine() << format("Atom[%d]: ", i);
       if (Atom.extractValue(AccelSection, DataOffset, FormParams)) {
         Atom.dump(W.getOStream());
-        if (Optional<uint64_t> Val = Atom.getAsUnsignedConstant()) {
+        if (std::optional<uint64_t> Val = Atom.getAsUnsignedConstant()) {
           StringRef Str = dwarf::AtomValueString(HdrData.Atoms[i].first, *Val);
           if (!Str.empty())
             W.getOStream() << " (" << Str << ")";
@@ -272,7 +272,7 @@ void AppleAcceleratorTable::Entry::extract(
     Atom.extractValue(AccelTable.AccelSection, Offset, FormParams);
 }
 
-Optional<DWARFFormValue>
+std::optional<DWARFFormValue>
 AppleAcceleratorTable::Entry::lookup(HeaderData::AtomType Atom) const {
   assert(HdrData && "Dereferencing end iterator?");
   assert(HdrData->Atoms.size() == Values.size());
@@ -283,19 +283,20 @@ AppleAcceleratorTable::Entry::lookup(HeaderData::AtomType Atom) const {
   return std::nullopt;
 }
 
-Optional<uint64_t> AppleAcceleratorTable::Entry::getDIESectionOffset() const {
+std::optional<uint64_t>
+AppleAcceleratorTable::Entry::getDIESectionOffset() const {
   return HdrData->extractOffset(lookup(dwarf::DW_ATOM_die_offset));
 }
 
-Optional<uint64_t> AppleAcceleratorTable::Entry::getCUOffset() const {
+std::optional<uint64_t> AppleAcceleratorTable::Entry::getCUOffset() const {
   return HdrData->extractOffset(lookup(dwarf::DW_ATOM_cu_offset));
 }
 
-Optional<dwarf::Tag> AppleAcceleratorTable::Entry::getTag() const {
-  Optional<DWARFFormValue> Tag = lookup(dwarf::DW_ATOM_die_tag);
+std::optional<dwarf::Tag> AppleAcceleratorTable::Entry::getTag() const {
+  std::optional<DWARFFormValue> Tag = lookup(dwarf::DW_ATOM_die_tag);
   if (!Tag)
     return std::nullopt;
-  if (Optional<uint64_t> Value = Tag->getAsUnsignedConstant())
+  if (std::optional<uint64_t> Value = Tag->getAsUnsignedConstant())
     return dwarf::Tag(*Value);
   return std::nullopt;
 }
@@ -534,7 +535,7 @@ DWARFDebugNames::Entry::Entry(const NameIndex &NameIdx, const Abbrev &Abbr)
     Values.emplace_back(Attr.Form);
 }
 
-Optional<DWARFFormValue>
+std::optional<DWARFFormValue>
 DWARFDebugNames::Entry::lookup(dwarf::Index Index) const {
   assert(Abbr->Attributes.size() == Values.size());
   for (auto Tuple : zip_first(Abbr->Attributes, Values)) {
@@ -544,14 +545,14 @@ DWARFDebugNames::Entry::lookup(dwarf::Index Index) const {
   return std::nullopt;
 }
 
-Optional<uint64_t> DWARFDebugNames::Entry::getDIEUnitOffset() const {
-  if (Optional<DWARFFormValue> Off = lookup(dwarf::DW_IDX_die_offset))
+std::optional<uint64_t> DWARFDebugNames::Entry::getDIEUnitOffset() const {
+  if (std::optional<DWARFFormValue> Off = lookup(dwarf::DW_IDX_die_offset))
     return Off->getAsReferenceUVal();
   return std::nullopt;
 }
 
-Optional<uint64_t> DWARFDebugNames::Entry::getCUIndex() const {
-  if (Optional<DWARFFormValue> Off = lookup(dwarf::DW_IDX_compile_unit))
+std::optional<uint64_t> DWARFDebugNames::Entry::getCUIndex() const {
+  if (std::optional<DWARFFormValue> Off = lookup(dwarf::DW_IDX_compile_unit))
     return Off->getAsUnsignedConstant();
   // In a per-CU index, the entries without a DW_IDX_compile_unit attribute
   // implicitly refer to the single CU.
@@ -560,8 +561,8 @@ Optional<uint64_t> DWARFDebugNames::Entry::getCUIndex() const {
   return std::nullopt;
 }
 
-Optional<uint64_t> DWARFDebugNames::Entry::getCUOffset() const {
-  Optional<uint64_t> Index = getCUIndex();
+std::optional<uint64_t> DWARFDebugNames::Entry::getCUOffset() const {
+  std::optional<uint64_t> Index = getCUIndex();
   if (!Index || *Index >= NameIdx->getCUCount())
     return std::nullopt;
   return NameIdx->getCUOffset(*Index);
@@ -683,7 +684,7 @@ bool DWARFDebugNames::NameIndex::dumpEntry(ScopedPrinter &W,
 
 void DWARFDebugNames::NameIndex::dumpName(ScopedPrinter &W,
                                           const NameTableEntry &NTE,
-                                          Optional<uint32_t> Hash) const {
+                                          std::optional<uint32_t> Hash) const {
   DictScope NameScope(W, ("Name " + Twine(NTE.getIndex())).str());
   if (Hash)
     W.printHex("Hash", *Hash);
@@ -793,7 +794,7 @@ LLVM_DUMP_METHOD void DWARFDebugNames::dump(raw_ostream &OS) const {
     NI.dump(W);
 }
 
-Optional<uint64_t>
+std::optional<uint64_t>
 DWARFDebugNames::ValueIterator::findEntryOffsetInCurrentIndex() {
   const Header &Hdr = CurrentIndex->Hdr;
   if (Hdr.BucketCount == 0) {
@@ -837,7 +838,7 @@ bool DWARFDebugNames::ValueIterator::getEntryAtCurrentOffset() {
 }
 
 bool DWARFDebugNames::ValueIterator::findInCurrentIndex() {
-  Optional<uint64_t> Offset = findEntryOffsetInCurrentIndex();
+  std::optional<uint64_t> Offset = findEntryOffsetInCurrentIndex();
   if (!Offset)
     return false;
   DataOffset = *Offset;
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index e1d74310a51a..d7118b835a0d 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -103,7 +103,7 @@ static void dumpUUID(raw_ostream &OS, const ObjectFile &Obj) {
 }
 
 using ContributionCollection =
-    std::vector<Optional<StrOffsetsContributionDescriptor>>;
+    std::vector<std::optional<StrOffsetsContributionDescriptor>>;
 
 // Collect all the contributions to the string offsets table from all units,
 // sort them by their starting offsets and remove duplicates.
@@ -117,8 +117,8 @@ collectContributionData(DWARFContext::unit_iterator_range Units) {
   // the start of the contributions vector. This way they are reported
   // first.
   llvm::sort(Contributions,
-             [](const Optional<StrOffsetsContributionDescriptor> &L,
-                const Optional<StrOffsetsContributionDescriptor> &R) {
+             [](const std::optional<StrOffsetsContributionDescriptor> &L,
+                const std::optional<StrOffsetsContributionDescriptor> &R) {
                if (L && R)
                  return L->Base < R->Base;
                return R.has_value();
@@ -129,8 +129,8 @@ collectContributionData(DWARFContext::unit_iterator_range Units) {
   // to report them more than once.
   Contributions.erase(
       std::unique(Contributions.begin(), Contributions.end(),
-                  [](const Optional<StrOffsetsContributionDescriptor> &L,
-                     const Optional<StrOffsetsContributionDescriptor> &R) {
+                  [](const std::optional<StrOffsetsContributionDescriptor> &L,
+                     const std::optional<StrOffsetsContributionDescriptor> &R) {
                     if (L && R)
                       return L->Base == R->Base && L->Size == R->Size;
                     return false;
@@ -245,7 +245,7 @@ static void dumpAddrSection(raw_ostream &OS, DWARFDataExtractor &AddrData,
 // Dump the .debug_rnglists or .debug_rnglists.dwo section (DWARF v5).
 static void dumpRnglistsSection(
     raw_ostream &OS, DWARFDataExtractor &rnglistData,
-    llvm::function_ref<Optional<object::SectionedAddress>(uint32_t)>
+    llvm::function_ref<std::optional<object::SectionedAddress>(uint32_t)>
         LookupPooledAddress,
     DIDumpOptions DumpOpts) {
   uint64_t Offset = 0;
@@ -312,7 +312,7 @@ static void dumpLoclistsSection(raw_ostream &OS, DIDumpOptions DumpOpts,
                                 DWARFDataExtractor Data,
                                 const MCRegisterInfo *MRI,
                                 const DWARFObject &Obj,
-                                Optional<uint64_t> DumpOffset) {
+                                std::optional<uint64_t> DumpOffset) {
   uint64_t Offset = 0;
 
   while (Data.isValidOffset(Offset)) {
@@ -351,7 +351,7 @@ static void dumpPubTableSection(raw_ostream &OS, DIDumpOptions DumpOpts,
 
 void DWARFContext::dump(
     raw_ostream &OS, DIDumpOptions DumpOpts,
-    std::array<Optional<uint64_t>, DIDT_ID_Count> DumpOffsets) {
+    std::array<std::optional<uint64_t>, DIDT_ID_Count> DumpOffsets) {
   uint64_t DumpType = DumpOpts.DumpType;
 
   StringRef Extension = sys::path::extension(DObj->getFileName());
@@ -368,7 +368,7 @@ void DWARFContext::dump(
   bool Explicit = DumpType != DIDT_All && !IsDWO;
   bool ExplicitDWO = Explicit && IsDWO;
   auto shouldDump = [&](bool Explicit, const char *Name, unsigned ID,
-                        StringRef Section) -> Optional<uint64_t> * {
+                        StringRef Section) -> std::optional<uint64_t> * {
     unsigned Mask = 1U << ID;
     bool Should = (DumpType & Mask) && (Explicit || !Section.empty());
     if (!Should)
@@ -459,7 +459,7 @@ void DWARFContext::dump(
     }
   }
 
-  if (const Optional<uint64_t> *Off =
+  if (const std::optional<uint64_t> *Off =
           shouldDump(Explicit, ".debug_frame", DIDT_ID_DebugFrame,
                      DObj->getFrameSection().Data)) {
     if (Expected<const DWARFDebugFrame *> DF = getDebugFrame())
@@ -468,7 +468,7 @@ void DWARFContext::dump(
       RecoverableErrorHandler(DF.takeError());
   }
 
-  if (const Optional<uint64_t> *Off =
+  if (const std::optional<uint64_t> *Off =
           shouldDump(Explicit, ".eh_frame", DIDT_ID_DebugFrame,
                      DObj->getEHFrameSection().Data)) {
     if (Expected<const DWARFDebugFrame *> DF = getEHFrame())
@@ -519,7 +519,7 @@ void DWARFContext::dump(
 
   auto DumpLineSection = [&](DWARFDebugLine::SectionParser Parser,
                              DIDumpOptions DumpOpts,
-                             Optional<uint64_t> DumpOffset) {
+                             std::optional<uint64_t> DumpOffset) {
     while (!Parser.done()) {
       if (DumpOffset && Parser.getOffset() != *DumpOffset) {
         Parser.skip(DumpOpts.WarningHandler, DumpOpts.WarningHandler);
@@ -612,7 +612,8 @@ void DWARFContext::dump(
     }
   }
 
-  auto LookupPooledAddress = [&](uint32_t Index) -> Optional<SectionedAddress> {
+  auto LookupPooledAddress =
+      [&](uint32_t Index) -> std::optional<SectionedAddress> {
     const auto &CUs = compile_units();
     auto I = CUs.begin();
     if (I == CUs.end())
@@ -712,7 +713,7 @@ DWARFTypeUnit *DWARFContext::getTypeUnitForHash(uint16_t Version, uint64_t Hash,
 
   struct UnitContainers {
     const DWARFUnitVector &Units;
-    Optional<DenseMap<uint64_t, DWARFTypeUnit *>> &Map;
+    std::optional<DenseMap<uint64_t, DWARFTypeUnit *>> &Map;
   };
   UnitContainers Units = IsDWO ? UnitContainers{DWOUnits, DWOTypeUnits}
                                : UnitContainers{NormalUnits, NormalTypeUnits};
@@ -744,8 +745,8 @@ DWARFCompileUnit *DWARFContext::getDWOCompileUnitForHash(uint64_t Hash) {
   for (const auto &DWOCU : dwo_compile_units()) {
     // Might not have parsed DWO ID yet.
     if (!DWOCU->getDWOId()) {
-      if (Optional<uint64_t> DWOId =
-          toUnsigned(DWOCU->getUnitDIE().find(DW_AT_GNU_dwo_id)))
+      if (std::optional<uint64_t> DWOId =
+              toUnsigned(DWOCU->getUnitDIE().find(DW_AT_GNU_dwo_id)))
         DWOCU->setDWOId(*DWOId);
       else
         // No DWO ID?
@@ -1111,7 +1112,7 @@ static bool getFunctionNameAndStartLineForAddress(
     DWARFCompileUnit *CU, uint64_t Address, FunctionNameKind Kind,
     DILineInfoSpecifier::FileLineInfoKind FileNameKind,
     std::string &FunctionName, std::string &StartFile, uint32_t &StartLine,
-    Optional<uint64_t> &StartAddress) {
+    std::optional<uint64_t> &StartAddress) {
   // The address may correspond to instruction in some inlined function,
   // so we have to build the chain of inlined functions and take the
   // name of the topmost function in it.
@@ -1141,9 +1142,9 @@ static bool getFunctionNameAndStartLineForAddress(
   return FoundResult;
 }
 
-static Optional<int64_t>
+static std::optional<int64_t>
 getExpressionFrameOffset(ArrayRef<uint8_t> Expr,
-                         Optional<unsigned> FrameBaseReg) {
+                         std::optional<unsigned> FrameBaseReg) {
   if (!Expr.empty() &&
       (Expr[0] == DW_OP_fbreg ||
        (FrameBaseReg && Expr[0] == DW_OP_breg0 + *FrameBaseReg))) {
@@ -1168,9 +1169,9 @@ void DWARFContext::addLocalsForDie(DWARFCompileUnit *CU, DWARFDie Subprogram,
     if (const char *Name = Subprogram.getSubroutineName(DINameKind::ShortName))
       Local.FunctionName = Name;
 
-    Optional<unsigned> FrameBaseReg;
+    std::optional<unsigned> FrameBaseReg;
     if (auto FrameBase = Subprogram.find(DW_AT_frame_base))
-      if (Optional<ArrayRef<uint8_t>> Expr = FrameBase->getAsBlock())
+      if (std::optional<ArrayRef<uint8_t>> Expr = FrameBase->getAsBlock())
         if (!Expr->empty() && (*Expr)[0] >= DW_OP_reg0 &&
             (*Expr)[0] <= DW_OP_reg31) {
           FrameBaseReg = (*Expr)[0] - DW_OP_reg0;
@@ -1179,7 +1180,7 @@ void DWARFContext::addLocalsForDie(DWARFCompileUnit *CU, DWARFDie Subprogram,
     if (Expected<std::vector<DWARFLocationExpression>> Loc =
             Die.getLocations(DW_AT_location)) {
       for (const auto &Entry : *Loc) {
-        if (Optional<int64_t> FrameOffset =
+        if (std::optional<int64_t> FrameOffset =
                 getExpressionFrameOffset(Entry.Expr, FrameBaseReg)) {
           Local.FrameOffset = *FrameOffset;
           break;
@@ -1198,7 +1199,7 @@ void DWARFContext::addLocalsForDie(DWARFCompileUnit *CU, DWARFDie Subprogram,
             Die.getAttributeValueAsReferencedDie(DW_AT_abstract_origin))
       Die = Origin;
     if (auto NameAttr = Die.find(DW_AT_name))
-      if (Optional<const char *> Name = dwarf::toString(*NameAttr))
+      if (std::optional<const char *> Name = dwarf::toString(*NameAttr))
         Local.Name = *Name;
     if (auto Type = Die.getAttributeValueAsReferencedDie(DW_AT_type))
       Local.Size = Type.getTypeSize(getCUAddrSize());
@@ -1285,7 +1286,7 @@ DILineInfoTable DWARFContext::getLineInfoForAddressRange(
   uint32_t StartLine = 0;
   std::string StartFileName;
   std::string FunctionName(DILineInfo::BadString);
-  Optional<uint64_t> StartAddress;
+  std::optional<uint64_t> StartAddress;
   getFunctionNameAndStartLineForAddress(CU, Address.Address, Spec.FNKind,
                                         Spec.FLIKind, FunctionName,
                                         StartFileName, StartLine, StartAddress);
@@ -1846,9 +1847,9 @@ public:
         if (Supports && Supports(Reloc.getType())) {
           auto I = Map->try_emplace(
               Reloc.getOffset(),
-              RelocAddrEntry{SymInfoOrErr->SectionIndex, Reloc,
-                             SymInfoOrErr->Address,
-                             Optional<object::RelocationRef>(), 0, Resolver});
+              RelocAddrEntry{
+                  SymInfoOrErr->SectionIndex, Reloc, SymInfoOrErr->Address,
+                  std::optional<object::RelocationRef>(), 0, Resolver});
           // If we didn't successfully insert that's because we already had a
           // relocation for that offset. Store it as a second relocation in the
           // same RelocAddrEntry instead.
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDataExtractor.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDataExtractor.cpp
index ff6ed2b66756..97434b3cfab8 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDataExtractor.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDataExtractor.cpp
@@ -68,7 +68,7 @@ uint64_t DWARFDataExtractor::getRelocatedValue(uint32_t Size, uint64_t *Off,
   return R;
 }
 
-Optional<uint64_t>
+std::optional<uint64_t>
 DWARFDataExtractor::getEncodedPointer(uint64_t *Offset, uint8_t Encoding,
                                       uint64_t PCRelOffset) const {
   if (Encoding == dwarf::DW_EH_PE_omit)
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugAddr.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugAddr.cpp
index fa13491e83b9..98eaf1a095d9 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugAddr.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugAddr.cpp
@@ -177,9 +177,8 @@ Expected<uint64_t> DWARFDebugAddrTable::getAddrEntry(uint32_t Index) const {
                            Index, Offset);
 }
 
-Optional<uint64_t> DWARFDebugAddrTable::getFullLength() const {
+std::optional<uint64_t> DWARFDebugAddrTable::getFullLength() const {
   if (Length == 0)
     return std::nullopt;
   return Length + dwarf::getUnitLengthFieldByteSize(Format);
 }
-
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp
index e9b657ea8271..2540291d0038 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp
@@ -63,13 +63,13 @@ UnwindLocation UnwindLocation::createAtCFAPlusOffset(int32_t Offset) {
 
 UnwindLocation
 UnwindLocation::createIsRegisterPlusOffset(uint32_t RegNum, int32_t Offset,
-                                           Optional<uint32_t> AddrSpace) {
+                                           std::optional<uint32_t> AddrSpace) {
   return {RegPlusOffset, RegNum, Offset, AddrSpace, false};
 }
 
 UnwindLocation
 UnwindLocation::createAtRegisterPlusOffset(uint32_t RegNum, int32_t Offset,
-                                           Optional<uint32_t> AddrSpace) {
+                                           std::optional<uint32_t> AddrSpace) {
   return {RegPlusOffset, RegNum, Offset, AddrSpace, true};
 }
 
@@ -571,7 +571,7 @@ Error UnwindTable::parseRows(const CFIProgram &CFIP, UnwindRow &Row,
       llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
       if (!RegNum)
         return RegNum.takeError();
-      if (Optional<UnwindLocation> O =
+      if (std::optional<UnwindLocation> O =
               InitialLocs->getRegisterLocation(*RegNum))
         Row.getRegisterLocations().setRegisterLocation(*RegNum, *O);
       else
@@ -1089,8 +1089,8 @@ Error DWARFDebugFrame::parse(DWARFDataExtractor Data) {
       StringRef AugmentationData("");
       uint32_t FDEPointerEncoding = DW_EH_PE_absptr;
       uint32_t LSDAPointerEncoding = DW_EH_PE_omit;
-      Optional<uint64_t> Personality;
-      Optional<uint32_t> PersonalityEncoding;
+      std::optional<uint64_t> Personality;
+      std::optional<uint32_t> PersonalityEncoding;
       if (IsEH) {
         std::optional<uint64_t> AugmentationLength;
         uint64_t StartAugmentationOffset;
@@ -1170,7 +1170,7 @@ Error DWARFDebugFrame::parse(DWARFDataExtractor Data) {
       uint64_t CIEPointer = Id;
       uint64_t InitialLocation = 0;
       uint64_t AddressRange = 0;
-      Optional<uint64_t> LSDAAddress;
+      std::optional<uint64_t> LSDAAddress;
       CIE *Cie = CIEs[IsEH ? (StartStructureOffset - CIEPointer) : CIEPointer];
 
       if (IsEH) {
@@ -1244,7 +1244,7 @@ FrameEntry *DWARFDebugFrame::getEntryAtOffset(uint64_t Offset) const {
 
 void DWARFDebugFrame::dump(raw_ostream &OS, DIDumpOptions DumpOpts,
                            const MCRegisterInfo *MRI,
-                           Optional<uint64_t> Offset) const {
+                           std::optional<uint64_t> Offset) const {
   if (Offset) {
     if (auto *Entry = getEntryAtOffset(*Offset))
       Entry->dump(OS, DumpOpts, MRI, IsEH);
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp
index 7dbeebc2770f..4cd22cda374a 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp
@@ -67,7 +67,8 @@ bool DWARFDebugInfoEntry::extractFast(const DWARFUnit &U, uint64_t *OffsetPtr,
   }
   // See if all attributes in this DIE have fixed byte sizes. If so, we can
   // just add this size to the offset to skip to the next DIE.
-  if (Optional<size_t> FixedSize = AbbrevDecl->getFixedAttributesByteSize(U)) {
+  if (std::optional<size_t> FixedSize =
+          AbbrevDecl->getFixedAttributesByteSize(U)) {
     *OffsetPtr += *FixedSize;
     return true;
   }
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
index 2bce28fe8a03..5e56330ee732 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
@@ -79,7 +79,8 @@ bool DWARFDebugLine::Prologue::hasFileAtIndex(uint64_t FileIndex) const {
   return FileIndex != 0 && FileIndex <= FileNames.size();
 }
 
-Optional<uint64_t> DWARFDebugLine::Prologue::getLastValidFileIndex() const {
+std::optional<uint64_t>
+DWARFDebugLine::Prologue::getLastValidFileIndex() const {
   if (FileNames.empty())
     return std::nullopt;
   uint16_t DwarfVersion = getVersion();
@@ -717,8 +718,8 @@ DWARFDebugLine::ParsingState::handleSpecialOpcode(uint8_t Opcode,
 /// Parse a ULEB128 using the specified \p Cursor. \returns the parsed value on
 /// success, or None if \p Cursor is in a failing state.
 template <typename T>
-static Optional<T> parseULEB128(DWARFDataExtractor &Data,
-                                DataExtractor::Cursor &Cursor) {
+static std::optional<T> parseULEB128(DWARFDataExtractor &Data,
+                                     DataExtractor::Cursor &Cursor) {
   T Value = Data.getULEB128(Cursor);
   if (Cursor)
     return Value;
@@ -1005,7 +1006,7 @@ Error DWARFDebugLine::LineTable::parse(
         // Takes a single unsigned LEB128 operand, multiplies it by the
         // min_inst_length field of the prologue, and adds the
         // result to the address register of the state machine.
-        if (Optional<uint64_t> Operand =
+        if (std::optional<uint64_t> Operand =
                 parseULEB128<uint64_t>(TableData, Cursor)) {
           uint64_t AddrOffset =
               State.advanceAddr(*Operand, Opcode, OpcodeOffset);
@@ -1030,7 +1031,7 @@ Error DWARFDebugLine::LineTable::parse(
       case DW_LNS_set_file:
         // Takes a single unsigned LEB128 operand and stores it in the file
         // register of the state machine.
-        if (Optional<uint16_t> File =
+        if (std::optional<uint16_t> File =
                 parseULEB128<uint16_t>(TableData, Cursor)) {
           State.Row.File = *File;
           if (Verbose)
@@ -1041,7 +1042,7 @@ Error DWARFDebugLine::LineTable::parse(
       case DW_LNS_set_column:
         // Takes a single unsigned LEB128 operand and stores it in the
         // column register of the state machine.
-        if (Optional<uint16_t> Column =
+        if (std::optional<uint16_t> Column =
                 parseULEB128<uint16_t>(TableData, Cursor)) {
           State.Row.Column = *Column;
           if (Verbose)
@@ -1117,7 +1118,8 @@ Error DWARFDebugLine::LineTable::parse(
       case DW_LNS_set_isa:
         // Takes a single unsigned LEB128 operand and stores it in the
         // ISA register of the state machine.
-        if (Optional<uint8_t> Isa = parseULEB128<uint8_t>(TableData, Cursor)) {
+        if (std::optional<uint8_t> Isa =
+                parseULEB128<uint8_t>(TableData, Cursor)) {
           State.Row.Isa = *Isa;
           if (Verbose)
             *OS << " (" << (uint64_t)State.Row.Isa << ")";
@@ -1135,7 +1137,7 @@ Error DWARFDebugLine::LineTable::parse(
           uint8_t OpcodeLength = Prologue.StandardOpcodeLengths[Opcode - 1];
           std::vector<uint64_t> Operands;
           for (uint8_t I = 0; I < OpcodeLength; ++I) {
-            if (Optional<uint64_t> Value =
+            if (std::optional<uint64_t> Value =
                     parseULEB128<uint64_t>(TableData, Cursor))
               Operands.push_back(*Value);
             else
@@ -1330,8 +1332,9 @@ bool DWARFDebugLine::LineTable::lookupAddressRangeImpl(
   return true;
 }
 
-Optional<StringRef> DWARFDebugLine::LineTable::getSourceByIndex(uint64_t FileIndex,
-                                                                FileLineInfoKind Kind) const {
+std::optional<StringRef>
+DWARFDebugLine::LineTable::getSourceByIndex(uint64_t FileIndex,
+                                            FileLineInfoKind Kind) const {
   if (Kind == FileLineInfoKind::None || !Prologue.hasFileAtIndex(FileIndex))
     return std::nullopt;
   const FileNameEntry &Entry = Prologue.getFileNameEntry(FileIndex);
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp
index 6a44052e3474..58c3889f2cc4 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp
@@ -30,16 +30,17 @@ class DWARFObject;
 
 namespace {
 class DWARFLocationInterpreter {
-  Optional<object::SectionedAddress> Base;
-  std::function<Optional<object::SectionedAddress>(uint32_t)> LookupAddr;
+  std::optional<object::SectionedAddress> Base;
+  std::function<std::optional<object::SectionedAddress>(uint32_t)> LookupAddr;
 
 public:
   DWARFLocationInterpreter(
-      Optional<object::SectionedAddress> Base,
-      std::function<Optional<object::SectionedAddress>(uint32_t)> LookupAddr)
+      std::optional<object::SectionedAddress> Base,
+      std::function<std::optional<object::SectionedAddress>(uint32_t)>
+          LookupAddr)
       : Base(Base), LookupAddr(std::move(LookupAddr)) {}
 
-  Expected<Optional<DWARFLocationExpression>>
+  Expected<std::optional<DWARFLocationExpression>>
   Interpret(const DWARFLocationEntry &E);
 };
 } // namespace
@@ -48,7 +49,7 @@ static Error createResolverError(uint32_t Index, unsigned Kind) {
   return make_error<ResolverError>(Index, (dwarf::LoclistEntries)Kind);
 }
 
-Expected<Optional<DWARFLocationExpression>>
+Expected<std::optional<DWARFLocationExpression>>
 DWARFLocationInterpreter::Interpret(const DWARFLocationEntry &E) {
   switch (E.Kind) {
   case dwarf::DW_LLE_end_of_list:
@@ -60,10 +61,10 @@ DWARFLocationInterpreter::Interpret(const DWARFLocationEntry &E) {
     return std::nullopt;
   }
   case dwarf::DW_LLE_startx_endx: {
-    Optional<SectionedAddress> LowPC = LookupAddr(E.Value0);
+    std::optional<SectionedAddress> LowPC = LookupAddr(E.Value0);
     if (!LowPC)
       return createResolverError(E.Value0, E.Kind);
-    Optional<SectionedAddress> HighPC = LookupAddr(E.Value1);
+    std::optional<SectionedAddress> HighPC = LookupAddr(E.Value1);
     if (!HighPC)
       return createResolverError(E.Value1, E.Kind);
     return DWARFLocationExpression{
@@ -71,7 +72,7 @@ DWARFLocationInterpreter::Interpret(const DWARFLocationEntry &E) {
         E.Loc};
   }
   case dwarf::DW_LLE_startx_length: {
-    Optional<SectionedAddress> LowPC = LookupAddr(E.Value0);
+    std::optional<SectionedAddress> LowPC = LookupAddr(E.Value0);
     if (!LowPC)
       return createResolverError(E.Value0, E.Kind);
     return DWARFLocationExpression{DWARFAddressRange{LowPC->Address,
@@ -120,21 +121,19 @@ static void dumpExpression(raw_ostream &OS, DIDumpOptions DumpOpts,
   DWARFExpression(Extractor, AddressSize).print(OS, DumpOpts, MRI, U);
 }
 
-bool DWARFLocationTable::dumpLocationList(uint64_t *Offset, raw_ostream &OS,
-                                          Optional<SectionedAddress> BaseAddr,
-                                          const MCRegisterInfo *MRI,
-                                          const DWARFObject &Obj, DWARFUnit *U,
-                                          DIDumpOptions DumpOpts,
-                                          unsigned Indent) const {
+bool DWARFLocationTable::dumpLocationList(
+    uint64_t *Offset, raw_ostream &OS, std::optional<SectionedAddress> BaseAddr,
+    const MCRegisterInfo *MRI, const DWARFObject &Obj, DWARFUnit *U,
+    DIDumpOptions DumpOpts, unsigned Indent) const {
   DWARFLocationInterpreter Interp(
-      BaseAddr, [U](uint32_t Index) -> Optional<SectionedAddress> {
+      BaseAddr, [U](uint32_t Index) -> std::optional<SectionedAddress> {
         if (U)
           return U->getAddrOffsetSectionItem(Index);
         return std::nullopt;
       });
   OS << format("0x%8.8" PRIx64 ": ", *Offset);
   Error E = visitLocationList(Offset, [&](const DWARFLocationEntry &E) {
-    Expected<Optional<DWARFLocationExpression>> Loc = Interp.Interpret(E);
+    Expected<std::optional<DWARFLocationExpression>> Loc = Interp.Interpret(E);
     if (!Loc || DumpOpts.DisplayRawContents)
       dumpRawEntry(E, OS, Indent, DumpOpts, Obj);
     if (Loc && *Loc) {
@@ -170,12 +169,12 @@ bool DWARFLocationTable::dumpLocationList(uint64_t *Offset, raw_ostream &OS,
 }
 
 Error DWARFLocationTable::visitAbsoluteLocationList(
-    uint64_t Offset, Optional<SectionedAddress> BaseAddr,
-    std::function<Optional<SectionedAddress>(uint32_t)> LookupAddr,
+    uint64_t Offset, std::optional<SectionedAddress> BaseAddr,
+    std::function<std::optional<SectionedAddress>(uint32_t)> LookupAddr,
     function_ref<bool(Expected<DWARFLocationExpression>)> Callback) const {
   DWARFLocationInterpreter Interp(BaseAddr, std::move(LookupAddr));
   return visitLocationList(&Offset, [&](const DWARFLocationEntry &E) {
-    Expected<Optional<DWARFLocationExpression>> Loc = Interp.Interpret(E);
+    Expected<std::optional<DWARFLocationExpression>> Loc = Interp.Interpret(E);
     if (!Loc)
       return Callback(Loc.takeError());
     if (*Loc)
@@ -186,7 +185,7 @@ Error DWARFLocationTable::visitAbsoluteLocationList(
 
 void DWARFDebugLoc::dump(raw_ostream &OS, const MCRegisterInfo *MRI,
                          const DWARFObject &Obj, DIDumpOptions DumpOpts,
-                         Optional<uint64_t> DumpOffset) const {
+                         std::optional<uint64_t> DumpOffset) const {
   auto BaseAddr = std::nullopt;
   unsigned Indent = 12;
   if (DumpOffset) {
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugMacro.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugMacro.cpp
index 80daea64814a..4d52046ba9ba 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugMacro.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugMacro.cpp
@@ -105,8 +105,8 @@ void DWARFDebugMacro::dump(raw_ostream &OS) const {
 }
 
 Error DWARFDebugMacro::parseImpl(
-    Optional<DWARFUnitVector::compile_unit_range> Units,
-    Optional<DataExtractor> StringExtractor, DWARFDataExtractor Data,
+    std::optional<DWARFUnitVector::compile_unit_range> Units,
+    std::optional<DataExtractor> StringExtractor, DWARFDataExtractor Data,
     bool IsMacro) {
   uint64_t Offset = 0;
   MacroList *M = nullptr;
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp
index cad3dcab8a7e..db01719bed59 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp
@@ -85,7 +85,7 @@ void DWARFDebugRangeList::dump(raw_ostream &OS) const {
 }
 
 DWARFAddressRangesVector DWARFDebugRangeList::getAbsoluteRanges(
-    llvm::Optional<object::SectionedAddress> BaseAddr) const {
+    std::optional<object::SectionedAddress> BaseAddr) const {
   DWARFAddressRangesVector Res;
   // debug_addr can't use the max integer tombstone because that's used for the
   // base address specifier entry - so use max-1.
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugRnglists.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugRnglists.cpp
index d12acca1962e..b428c2adfe0b 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugRnglists.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugRnglists.cpp
@@ -86,15 +86,15 @@ Error RangeListEntry::extract(DWARFDataExtractor Data, uint64_t *OffsetPtr) {
 }
 
 DWARFAddressRangesVector DWARFDebugRnglist::getAbsoluteRanges(
-    llvm::Optional<object::SectionedAddress> BaseAddr, DWARFUnit &U) const {
+    std::optional<object::SectionedAddress> BaseAddr, DWARFUnit &U) const {
   return getAbsoluteRanges(
       BaseAddr, U.getAddressByteSize(),
       [&](uint32_t Index) { return U.getAddrOffsetSectionItem(Index); });
 }
 
 DWARFAddressRangesVector DWARFDebugRnglist::getAbsoluteRanges(
-    Optional<object::SectionedAddress> BaseAddr, uint8_t AddressByteSize,
-    function_ref<Optional<object::SectionedAddress>(uint32_t)>
+    std::optional<object::SectionedAddress> BaseAddr, uint8_t AddressByteSize,
+    function_ref<std::optional<object::SectionedAddress>(uint32_t)>
         LookupPooledAddress) const {
   DWARFAddressRangesVector Res;
   uint64_t Tombstone = dwarf::computeTombstoneAddress(AddressByteSize);
@@ -175,7 +175,7 @@ DWARFAddressRangesVector DWARFDebugRnglist::getAbsoluteRanges(
 void RangeListEntry::dump(
     raw_ostream &OS, uint8_t AddrSize, uint8_t MaxEncodingStringLength,
     uint64_t &CurrentBase, DIDumpOptions DumpOpts,
-    llvm::function_ref<Optional<object::SectionedAddress>(uint32_t)>
+    llvm::function_ref<std::optional<object::SectionedAddress>(uint32_t)>
         LookupPooledAddress) const {
   auto PrintRawEntry = [](raw_ostream &OS, const RangeListEntry &Entry,
                           uint8_t AddrSize, DIDumpOptions DumpOpts) {
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
index d6f0ee4312e8..9c94b5121a5b 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
@@ -137,7 +137,7 @@ static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
   if (Attr == DW_AT_decl_file || Attr == DW_AT_call_file) {
     Color = HighlightColor::String;
     if (const auto *LT = U->getContext().getLineTableForUnit(U)) {
-      if (Optional<uint64_t> Val = FormValue.getAsUnsignedConstant()) {
+      if (std::optional<uint64_t> Val = FormValue.getAsUnsignedConstant()) {
         if (LT->getFileNameByIndex(
                 *Val, U->getCompilationDir(),
                 DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath,
@@ -147,13 +147,13 @@ static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
         }
       }
     }
-  } else if (Optional<uint64_t> Val = FormValue.getAsUnsignedConstant())
+  } else if (std::optional<uint64_t> Val = FormValue.getAsUnsignedConstant())
     Name = AttributeValueString(Attr, *Val);
 
   if (!Name.empty())
     WithColor(OS, Color) << Name;
   else if (Attr == DW_AT_decl_line || Attr == DW_AT_call_line) {
-    if (Optional<uint64_t> Val = FormValue.getAsUnsignedConstant())
+    if (std::optional<uint64_t> Val = FormValue.getAsUnsignedConstant())
       OS << *Val;
     else
       FormValue.dump(OS, DumpOpts);
@@ -207,7 +207,7 @@ static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
       OS << '"';
     }
   } else if (Attr == DW_AT_APPLE_property_attribute) {
-    if (Optional<uint64_t> OptVal = FormValue.getAsUnsignedConstant())
+    if (std::optional<uint64_t> OptVal = FormValue.getAsUnsignedConstant())
       dumpApplePropertyAttribute(OS, *OptVal);
   } else if (Attr == DW_AT_ranges) {
     const DWARFObject &Obj = Die.getDwarfUnit()->getContext().getDWARFObj();
@@ -249,7 +249,7 @@ bool DWARFDie::isSubroutineDIE() const {
   return Tag == DW_TAG_subprogram || Tag == DW_TAG_inlined_subroutine;
 }
 
-Optional<DWARFFormValue> DWARFDie::find(dwarf::Attribute Attr) const {
+std::optional<DWARFFormValue> DWARFDie::find(dwarf::Attribute Attr) const {
   if (!isValid())
     return std::nullopt;
   auto AbbrevDecl = getAbbreviationDeclarationPtr();
@@ -258,7 +258,7 @@ Optional<DWARFFormValue> DWARFDie::find(dwarf::Attribute Attr) const {
   return std::nullopt;
 }
 
-Optional<DWARFFormValue>
+std::optional<DWARFFormValue>
 DWARFDie::find(ArrayRef<dwarf::Attribute> Attrs) const {
   if (!isValid())
     return std::nullopt;
@@ -272,7 +272,7 @@ DWARFDie::find(ArrayRef<dwarf::Attribute> Attrs) const {
   return std::nullopt;
 }
 
-Optional<DWARFFormValue>
+std::optional<DWARFFormValue>
 DWARFDie::findRecursively(ArrayRef<dwarf::Attribute> Attrs) const {
   SmallVector<DWARFDie, 3> Worklist;
   Worklist.push_back(*this);
@@ -307,7 +307,7 @@ DWARFDie::findRecursively(ArrayRef<dwarf::Attribute> Attrs) const {
 
 DWARFDie
 DWARFDie::getAttributeValueAsReferencedDie(dwarf::Attribute Attr) const {
-  if (Optional<DWARFFormValue> F = find(Attr))
+  if (std::optional<DWARFFormValue> F = find(Attr))
     return getAttributeValueAsReferencedDie(*F);
   return DWARFDie();
 }
@@ -328,7 +328,7 @@ DWARFDie::getAttributeValueAsReferencedDie(const DWARFFormValue &V) const {
 
 DWARFDie DWARFDie::resolveTypeUnitReference() const {
   if (auto Attr = find(DW_AT_signature)) {
-    if (Optional<uint64_t> Sig = Attr->getAsReferenceUVal()) {
+    if (std::optional<uint64_t> Sig = Attr->getAsReferenceUVal()) {
       if (DWARFTypeUnit *TU = U->getContext().getTypeUnitForHash(
               U->getVersion(), *Sig, U->isDWOUnit()))
         return TU->getDIEForOffset(TU->getTypeOffset() + TU->getOffset());
@@ -337,15 +337,15 @@ DWARFDie DWARFDie::resolveTypeUnitReference() const {
   return *this;
 }
 
-Optional<uint64_t> DWARFDie::getRangesBaseAttribute() const {
+std::optional<uint64_t> DWARFDie::getRangesBaseAttribute() const {
   return toSectionOffset(find({DW_AT_rnglists_base, DW_AT_GNU_ranges_base}));
 }
 
-Optional<uint64_t> DWARFDie::getLocBaseAttribute() const {
+std::optional<uint64_t> DWARFDie::getLocBaseAttribute() const {
   return toSectionOffset(find(DW_AT_loclists_base));
 }
 
-Optional<uint64_t> DWARFDie::getHighPC(uint64_t LowPC) const {
+std::optional<uint64_t> DWARFDie::getHighPC(uint64_t LowPC) const {
   uint64_t Tombstone = dwarf::computeTombstoneAddress(U->getAddressByteSize());
   if (LowPC == Tombstone)
     return std::nullopt;
@@ -385,7 +385,7 @@ Expected<DWARFAddressRangesVector> DWARFDie::getAddressRanges() const {
   if (getLowAndHighPC(LowPC, HighPC, Index))
     return DWARFAddressRangesVector{{LowPC, HighPC, Index}};
 
-  Optional<DWARFFormValue> Value = find(DW_AT_ranges);
+  std::optional<DWARFFormValue> Value = find(DW_AT_ranges);
   if (Value) {
     if (Value->getForm() == DW_FORM_rnglistx)
       return U->findRnglistFromIndex(*Value->getAsSectionOffset());
@@ -409,12 +409,12 @@ bool DWARFDie::addressRangeContainsAddress(const uint64_t Address) const {
 
 Expected<DWARFLocationExpressionsVector>
 DWARFDie::getLocations(dwarf::Attribute Attr) const {
-  Optional<DWARFFormValue> Location = find(Attr);
+  std::optional<DWARFFormValue> Location = find(Attr);
   if (!Location)
     return createStringError(inconvertibleErrorCode(), "No %s",
                              dwarf::AttributeString(Attr).data());
 
-  if (Optional<uint64_t> Off = Location->getAsSectionOffset()) {
+  if (std::optional<uint64_t> Off = Location->getAsSectionOffset()) {
     uint64_t Offset = *Off;
 
     if (Location->getForm() == DW_FORM_loclistx) {
@@ -427,7 +427,7 @@ DWARFDie::getLocations(dwarf::Attribute Attr) const {
     return U->findLoclistFromOffset(Offset);
   }
 
-  if (Optional<ArrayRef<uint8_t>> Expr = Location->getAsBlock()) {
+  if (std::optional<ArrayRef<uint8_t>> Expr = Location->getAsBlock()) {
     return DWARFLocationExpressionsVector{
         DWARFLocationExpression{std::nullopt, to_vector<4>(*Expr)}};
   }
@@ -492,9 +492,9 @@ void DWARFDie::getCallerFrame(uint32_t &CallFile, uint32_t &CallLine,
   CallDiscriminator = toUnsigned(find(DW_AT_GNU_discriminator), 0);
 }
 
-Optional<uint64_t> DWARFDie::getTypeSize(uint64_t PointerSize) {
+std::optional<uint64_t> DWARFDie::getTypeSize(uint64_t PointerSize) {
   if (auto SizeAttr = find(DW_AT_byte_size))
-    if (Optional<uint64_t> Size = SizeAttr->getAsUnsignedConstant())
+    if (std::optional<uint64_t> Size = SizeAttr->getAsUnsignedConstant())
       return Size;
 
   switch (getTag()) {
@@ -521,7 +521,7 @@ Optional<uint64_t> DWARFDie::getTypeSize(uint64_t PointerSize) {
     DWARFDie BaseType = getAttributeValueAsReferencedDie(DW_AT_type);
     if (!BaseType)
       return std::nullopt;
-    Optional<uint64_t> BaseSize = BaseType.getTypeSize(PointerSize);
+    std::optional<uint64_t> BaseSize = BaseType.getTypeSize(PointerSize);
     if (!BaseSize)
       return std::nullopt;
     uint64_t Size = *BaseSize;
@@ -530,11 +530,11 @@ Optional<uint64_t> DWARFDie::getTypeSize(uint64_t PointerSize) {
         continue;
 
       if (auto ElemCountAttr = Child.find(DW_AT_count))
-        if (Optional<uint64_t> ElemCount =
+        if (std::optional<uint64_t> ElemCount =
                 ElemCountAttr->getAsUnsignedConstant())
           Size *= *ElemCount;
       if (auto UpperBoundAttr = Child.find(DW_AT_upper_bound))
-        if (Optional<int64_t> UpperBound =
+        if (std::optional<int64_t> UpperBound =
                 UpperBoundAttr->getAsSignedConstant()) {
           int64_t LowerBound = 0;
           if (auto LowerBoundAttr = Child.find(DW_AT_lower_bound))
@@ -592,7 +592,7 @@ void DWARFDie::dump(raw_ostream &OS, unsigned Indent,
         if (DumpOpts.Verbose) {
           OS << format(" [%u] %c", abbrCode,
                        AbbrevDecl->hasChildren() ? '*' : ' ');
-          if (Optional<uint32_t> ParentIdx = Die->getParentIdx())
+          if (std::optional<uint32_t> ParentIdx = Die->getParentIdx())
             OS << format(" (0x%8.8" PRIx64 ")",
                          U->getDIEAtIndex(*ParentIdx).getOffset());
         }
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp b/llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp
index b9d5ddd8ab9d..061b656bf9aa 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp
@@ -119,7 +119,7 @@ static DWARFExpression::Operation::Description getOpDesc(unsigned OpCode) {
 
 bool DWARFExpression::Operation::extract(DataExtractor Data,
                                          uint8_t AddressSize, uint64_t Offset,
-                                         Optional<DwarfFormat> Format) {
+                                         std::optional<DwarfFormat> Format) {
   EndOffset = Offset;
   Opcode = Data.getU8(&Offset);
 
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp b/llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp
index 99b92f11cfdb..5be55f26688b 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFFormValue.cpp
@@ -173,7 +173,7 @@ bool DWARFFormValue::skipValue(dwarf::Form Form, DataExtractor DebugInfoData,
     case DW_FORM_GNU_ref_alt:
     case DW_FORM_GNU_strp_alt:
     case DW_FORM_implicit_const:
-      if (Optional<uint8_t> FixedSize =
+      if (std::optional<uint8_t> FixedSize =
               dwarf::getFixedFormByteSize(Form, Params)) {
         *OffsetPtr += *FixedSize;
         return true;
@@ -427,7 +427,8 @@ void DWARFFormValue::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
       OS << "<invalid dwarf unit>";
       break;
     }
-    Optional<object::SectionedAddress> A = U->getAddrOffsetSectionItem(UValue);
+    std::optional<object::SectionedAddress> A =
+        U->getAddrOffsetSectionItem(UValue);
     if (!A || DumpOpts.Verbose)
       AddrOS << format("indexed (%8.8x) address = ", (uint32_t)UValue);
     if (A)
@@ -443,7 +444,8 @@ void DWARFFormValue::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
     }
     uint32_t Index = UValue >> 32;
     uint32_t Offset = UValue & 0xffffffff;
-    Optional<object::SectionedAddress> A = U->getAddrOffsetSectionItem(Index);
+    std::optional<object::SectionedAddress> A =
+        U->getAddrOffsetSectionItem(Index);
     if (!A || DumpOpts.Verbose)
       AddrOS << format("indexed (%8.8x) + 0x%x address = ", Index, Offset);
     if (A) {
@@ -666,13 +668,13 @@ Expected<const char *> DWARFFormValue::getAsCString() const {
       inconvertibleErrorCode());
 }
 
-Optional<uint64_t> DWARFFormValue::getAsAddress() const {
+std::optional<uint64_t> DWARFFormValue::getAsAddress() const {
   if (auto SA = getAsSectionedAddress())
     return SA->Address;
   return std::nullopt;
 }
 
-Optional<object::SectionedAddress>
+std::optional<object::SectionedAddress>
 DWARFFormValue::getAsSectionedAddress() const {
   if (!isFormClass(FC_Address))
     return std::nullopt;
@@ -682,7 +684,8 @@ DWARFFormValue::getAsSectionedAddress() const {
     uint32_t Index = AddrOffset ? (Value.uval >> 32) : Value.uval;
     if (!U)
       return std::nullopt;
-    Optional<object::SectionedAddress> SA = U->getAddrOffsetSectionItem(Index);
+    std::optional<object::SectionedAddress> SA =
+        U->getAddrOffsetSectionItem(Index);
     if (!SA)
       return std::nullopt;
     if (AddrOffset)
@@ -692,13 +695,14 @@ DWARFFormValue::getAsSectionedAddress() const {
   return {{Value.uval, Value.SectionIndex}};
 }
 
-Optional<uint64_t> DWARFFormValue::getAsReference() const {
+std::optional<uint64_t> DWARFFormValue::getAsReference() const {
   if (auto R = getAsRelativeReference())
     return R->Unit ? R->Unit->getOffset() + R->Offset : R->Offset;
   return std::nullopt;
 }
 
-Optional<DWARFFormValue::UnitOffset> DWARFFormValue::getAsRelativeReference() const {
+std::optional<DWARFFormValue::UnitOffset>
+DWARFFormValue::getAsRelativeReference() const {
   if (!isFormClass(FC_Reference))
     return std::nullopt;
   switch (Form) {
@@ -719,20 +723,20 @@ Optional<DWARFFormValue::UnitOffset> DWARFFormValue::getAsRelativeReference() co
   }
 }
 
-Optional<uint64_t> DWARFFormValue::getAsSectionOffset() const {
+std::optional<uint64_t> DWARFFormValue::getAsSectionOffset() const {
   if (!isFormClass(FC_SectionOffset))
     return std::nullopt;
   return Value.uval;
 }
 
-Optional<uint64_t> DWARFFormValue::getAsUnsignedConstant() const {
+std::optional<uint64_t> DWARFFormValue::getAsUnsignedConstant() const {
   if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) ||
       Form == DW_FORM_sdata)
     return std::nullopt;
   return Value.uval;
 }
 
-Optional<int64_t> DWARFFormValue::getAsSignedConstant() const {
+std::optional<int64_t> DWARFFormValue::getAsSignedConstant() const {
   if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) ||
       (Form == DW_FORM_udata &&
        uint64_t(std::numeric_limits<int64_t>::max()) < Value.uval))
@@ -751,26 +755,26 @@ Optional<int64_t> DWARFFormValue::getAsSignedConstant() const {
   }
 }
 
-Optional<ArrayRef<uint8_t>> DWARFFormValue::getAsBlock() const {
+std::optional<ArrayRef<uint8_t>> DWARFFormValue::getAsBlock() const {
   if (!isFormClass(FC_Block) && !isFormClass(FC_Exprloc) &&
       Form != DW_FORM_data16)
     return std::nullopt;
   return makeArrayRef(Value.data, Value.uval);
 }
 
-Optional<uint64_t> DWARFFormValue::getAsCStringOffset() const {
+std::optional<uint64_t> DWARFFormValue::getAsCStringOffset() const {
   if (!isFormClass(FC_String) && Form == DW_FORM_string)
     return std::nullopt;
   return Value.uval;
 }
 
-Optional<uint64_t> DWARFFormValue::getAsReferenceUVal() const {
+std::optional<uint64_t> DWARFFormValue::getAsReferenceUVal() const {
   if (!isFormClass(FC_Reference))
     return std::nullopt;
   return Value.uval;
 }
 
-Optional<std::string>
+std::optional<std::string>
 DWARFFormValue::getAsFile(DILineInfoSpecifier::FileLineInfoKind Kind) const {
   if (U == nullptr || !isFormClass(FC_Constant))
     return std::nullopt;
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFTypePrinter.cpp b/llvm/lib/DebugInfo/DWARF/DWARFTypePrinter.cpp
index aca0932e0f61..6a1423d37d9f 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFTypePrinter.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFTypePrinter.cpp
@@ -19,19 +19,19 @@ void DWARFTypePrinter::appendArrayType(const DWARFDie &D) {
   for (const DWARFDie &C : D.children()) {
     if (C.getTag() != DW_TAG_subrange_type)
       continue;
-    Optional<uint64_t> LB;
-    Optional<uint64_t> Count;
-    Optional<uint64_t> UB;
-    Optional<unsigned> DefaultLB;
-    if (Optional<DWARFFormValue> L = C.find(DW_AT_lower_bound))
+    std::optional<uint64_t> LB;
+    std::optional<uint64_t> Count;
+    std::optional<uint64_t> UB;
+    std::optional<unsigned> DefaultLB;
+    if (std::optional<DWARFFormValue> L = C.find(DW_AT_lower_bound))
       LB = L->getAsUnsignedConstant();
-    if (Optional<DWARFFormValue> CountV = C.find(DW_AT_count))
+    if (std::optional<DWARFFormValue> CountV = C.find(DW_AT_count))
       Count = CountV->getAsUnsignedConstant();
-    if (Optional<DWARFFormValue> UpperV = C.find(DW_AT_upper_bound))
+    if (std::optional<DWARFFormValue> UpperV = C.find(DW_AT_upper_bound))
       UB = UpperV->getAsUnsignedConstant();
-    if (Optional<DWARFFormValue> LV =
+    if (std::optional<DWARFFormValue> LV =
             D.getDwarfUnit()->getUnitDIE().find(DW_AT_language))
-      if (Optional<uint64_t> LC = LV->getAsUnsignedConstant())
+      if (std::optional<uint64_t> LC = LV->getAsUnsignedConstant())
         if ((DefaultLB =
                  LanguageLowerBound(static_cast<dwarf::SourceLanguage>(*LC))))
           if (LB && *LB == *DefaultLB)
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
index 77b2b68ef62f..522357b7edc1 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
@@ -204,7 +204,7 @@ DWARFDataExtractor DWARFUnit::getDebugInfoExtractor() const {
                             getAddressByteSize());
 }
 
-Optional<object::SectionedAddress>
+std::optional<object::SectionedAddress>
 DWARFUnit::getAddrOffsetSectionItem(uint32_t Index) const {
   if (!AddrOffsetSectionBase) {
     auto R = Context.info_section_units();
@@ -499,7 +499,8 @@ Error DWARFUnit::tryExtractDIEsIfNeeded(bool CUDieOnly) {
     return Error::success();
 
   DWARFDie UnitDie(this, &DieArray[0]);
-  if (Optional<uint64_t> DWOId = toUnsigned(UnitDie.find(DW_AT_GNU_dwo_id)))
+  if (std::optional<uint64_t> DWOId =
+          toUnsigned(UnitDie.find(DW_AT_GNU_dwo_id)))
     Header.setDWOId(*DWOId);
   if (!IsDWO) {
     assert(AddrOffsetSectionBase == std::nullopt);
@@ -828,7 +829,7 @@ void DWARFUnit::updateVariableDieMap(DWARFDie Die) {
   // exact address.
   uint64_t GVSize = 1;
   if (DWARFDie BaseType = Die.getAttributeValueAsReferencedDie(DW_AT_type))
-    if (Optional<uint64_t> Size = Die.getTypeSize(getAddressByteSize()))
+    if (std::optional<uint64_t> Size = Die.getTypeSize(getAddressByteSize()))
       GVSize = *Size;
 
   if (Address != UINT64_MAX)
@@ -898,7 +899,7 @@ DWARFUnit::getParentEntry(const DWARFDebugInfoEntry *Die) const {
     return nullptr;
   assert(Die >= DieArray.data() && Die < DieArray.data() + DieArray.size());
 
-  if (Optional<uint32_t> ParentIdx = Die->getParentIdx()) {
+  if (std::optional<uint32_t> ParentIdx = Die->getParentIdx()) {
     assert(*ParentIdx < DieArray.size() &&
            "ParentIdx is out of DieArray boundaries");
     return getDebugInfoEntry(*ParentIdx);
@@ -920,7 +921,7 @@ DWARFUnit::getSiblingEntry(const DWARFDebugInfoEntry *Die) const {
     return nullptr;
   assert(Die >= DieArray.data() && Die < DieArray.data() + DieArray.size());
 
-  if (Optional<uint32_t> SiblingIdx = Die->getSiblingIdx()) {
+  if (std::optional<uint32_t> SiblingIdx = Die->getSiblingIdx()) {
     assert(*SiblingIdx < DieArray.size() &&
            "SiblingIdx is out of DieArray boundaries");
     return &DieArray[*SiblingIdx];
@@ -942,7 +943,7 @@ DWARFUnit::getPreviousSiblingEntry(const DWARFDebugInfoEntry *Die) const {
     return nullptr;
   assert(Die >= DieArray.data() && Die < DieArray.data() + DieArray.size());
 
-  Optional<uint32_t> ParentIdx = Die->getParentIdx();
+  std::optional<uint32_t> ParentIdx = Die->getParentIdx();
   if (!ParentIdx)
     // Die is a root die, there is no previous sibling.
     return nullptr;
@@ -1009,7 +1010,7 @@ DWARFUnit::getLastChildEntry(const DWARFDebugInfoEntry *Die) const {
   if (!Die->hasChildren())
     return nullptr;
 
-  if (Optional<uint32_t> SiblingIdx = Die->getSiblingIdx()) {
+  if (std::optional<uint32_t> SiblingIdx = Die->getSiblingIdx()) {
     assert(*SiblingIdx < DieArray.size() &&
            "SiblingIdx is out of DieArray boundaries");
     assert(DieArray[*SiblingIdx - 1].getTag() == dwarf::DW_TAG_null &&
@@ -1044,12 +1045,13 @@ const DWARFAbbreviationDeclarationSet *DWARFUnit::getAbbreviations() const {
   return Abbrevs;
 }
 
-llvm::Optional<object::SectionedAddress> DWARFUnit::getBaseAddress() {
+std::optional<object::SectionedAddress> DWARFUnit::getBaseAddress() {
   if (BaseAddr)
     return BaseAddr;
 
   DWARFDie UnitDie = getUnitDIE();
-  Optional<DWARFFormValue> PC = UnitDie.find({DW_AT_low_pc, DW_AT_entry_pc});
+  std::optional<DWARFFormValue> PC =
+      UnitDie.find({DW_AT_low_pc, DW_AT_entry_pc});
   BaseAddr = toSectionedAddress(PC);
   return BaseAddr;
 }
@@ -1133,7 +1135,7 @@ parseDWARFStringOffsetsTableHeader(DWARFDataExtractor &DA,
   return Desc.validateContributionSize(DA);
 }
 
-Expected<Optional<StrOffsetsContributionDescriptor>>
+Expected<std::optional<StrOffsetsContributionDescriptor>>
 DWARFUnit::determineStringOffsetsTableContribution(DWARFDataExtractor &DA) {
   assert(!IsDWO);
   auto OptOffset = toSectionOffset(getUnitDIE().find(DW_AT_str_offsets_base));
@@ -1146,8 +1148,8 @@ DWARFUnit::determineStringOffsetsTableContribution(DWARFDataExtractor &DA) {
   return *DescOrError;
 }
 
-Expected<Optional<StrOffsetsContributionDescriptor>>
-DWARFUnit::determineStringOffsetsTableContributionDWO(DWARFDataExtractor & DA) {
+Expected<std::optional<StrOffsetsContributionDescriptor>>
+DWARFUnit::determineStringOffsetsTableContributionDWO(DWARFDataExtractor &DA) {
   assert(IsDWO);
   uint64_t Offset = 0;
   auto IndexEntry = Header.getIndexEntry();
@@ -1183,19 +1185,19 @@ DWARFUnit::determineStringOffsetsTableContributionDWO(DWARFDataExtractor & DA) {
   return *DescOrError;
 }
 
-Optional<uint64_t> DWARFUnit::getRnglistOffset(uint32_t Index) {
+std::optional<uint64_t> DWARFUnit::getRnglistOffset(uint32_t Index) {
   DataExtractor RangesData(RangeSection->Data, IsLittleEndian,
                            getAddressByteSize());
   DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
                               IsLittleEndian, 0);
-  if (Optional<uint64_t> Off = llvm::DWARFListTableHeader::getOffsetEntry(
+  if (std::optional<uint64_t> Off = llvm::DWARFListTableHeader::getOffsetEntry(
           RangesData, RangeSectionBase, getFormat(), Index))
     return *Off + RangeSectionBase;
   return std::nullopt;
 }
 
-Optional<uint64_t> DWARFUnit::getLoclistOffset(uint32_t Index) {
-  if (Optional<uint64_t> Off = llvm::DWARFListTableHeader::getOffsetEntry(
+std::optional<uint64_t> DWARFUnit::getLoclistOffset(uint32_t Index) {
+  if (std::optional<uint64_t> Off = llvm::DWARFListTableHeader::getOffsetEntry(
           LocTable->getData(), LocSectionBase, getFormat(), Index))
     return *Off + LocSectionBase;
   return std::nullopt;
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
index 26e92781c5fd..20cd0560333e 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
@@ -43,7 +43,7 @@ namespace llvm {
 class DWARFDebugInfoEntry;
 }
 
-Optional<DWARFAddressRange>
+std::optional<DWARFAddressRange>
 DWARFVerifier::DieRangeInfo::insert(const DWARFAddressRange &R) {
   auto Begin = Ranges.begin();
   auto End = Ranges.end();
@@ -284,11 +284,10 @@ unsigned DWARFVerifier::verifyDebugInfoCallSite(const DWARFDie &Die) {
     return 1;
   }
 
-  Optional<DWARFFormValue> CallAttr =
-      Curr.find({DW_AT_call_all_calls, DW_AT_call_all_source_calls,
-                 DW_AT_call_all_tail_calls, DW_AT_GNU_all_call_sites,
-                 DW_AT_GNU_all_source_call_sites,
-                 DW_AT_GNU_all_tail_call_sites});
+  std::optional<DWARFFormValue> CallAttr = Curr.find(
+      {DW_AT_call_all_calls, DW_AT_call_all_source_calls,
+       DW_AT_call_all_tail_calls, DW_AT_GNU_all_call_sites,
+       DW_AT_GNU_all_source_call_sites, DW_AT_GNU_all_tail_call_sites});
   if (!CallAttr) {
     error() << "Subprogram with call site entry has no DW_AT_call attribute:";
     Curr.dump(OS);
@@ -679,7 +678,8 @@ unsigned DWARFVerifier::verifyDebugInfoAttribute(const DWARFDie &Die,
       if (LT) {
         if (!LT->hasFileAtIndex(*FileIdx)) {
           bool IsZeroIndexed = LT->Prologue.getVersion() >= 5;
-          if (Optional<uint64_t> LastFileIdx = LT->getLastValidFileIndex()) {
+          if (std::optional<uint64_t> LastFileIdx =
+                  LT->getLastValidFileIndex()) {
             ReportError("DIE has " + AttributeString(Attr) +
                         " with an invalid file index " +
                         llvm::formatv("{0}", *FileIdx) +
@@ -732,7 +732,7 @@ unsigned DWARFVerifier::verifyDebugInfoForm(const DWARFDie &Die,
   case DW_FORM_ref8:
   case DW_FORM_ref_udata: {
     // Verify all CU relative references are valid CU offsets.
-    Optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
+    std::optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
     assert(RefVal);
     if (RefVal) {
       auto CUSize = DieCU->getNextUnitOffset() - DieCU->getOffset();
@@ -756,7 +756,7 @@ unsigned DWARFVerifier::verifyDebugInfoForm(const DWARFDie &Die,
   case DW_FORM_ref_addr: {
     // Verify all absolute DIE references have valid offsets in the
     // .debug_info section.
-    Optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
+    std::optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
     assert(RefVal);
     if (RefVal) {
       if (*RefVal >= DieCU->getInfoSection().Data.size()) {
diff --git a/llvm/lib/DebugInfo/GSYM/DwarfTransformer.cpp b/llvm/lib/DebugInfo/GSYM/DwarfTransformer.cpp
index b7e03e9885a3..d266960ae302 100644
--- a/llvm/lib/DebugInfo/GSYM/DwarfTransformer.cpp
+++ b/llvm/lib/DebugInfo/GSYM/DwarfTransformer.cpp
@@ -429,7 +429,7 @@ Error DwarfTransformer::convert(uint32_t NumThreads) {
   size_t NumBefore = Gsym.getNumFunctionInfos();
   auto getDie = [&](DWARFUnit &DwarfUnit) -> DWARFDie {
     DWARFDie ReturnDie = DwarfUnit.getUnitDIE(false);
-    if (llvm::Optional<uint64_t> DWOId = DwarfUnit.getDWOId()) {
+    if (std::optional<uint64_t> DWOId = DwarfUnit.getDWOId()) {
       DWARFUnit *DWOCU = DwarfUnit.getNonSkeletonUnitDIE(false).getDwarfUnit();
       if (!DWOCU->isDWOUnit()) {
         std::string DWOName = dwarf::toString(
diff --git a/llvm/lib/DebugInfo/GSYM/FunctionInfo.cpp b/llvm/lib/DebugInfo/GSYM/FunctionInfo.cpp
index b7d711d0f875..51058fc09cf1 100644
--- a/llvm/lib/DebugInfo/GSYM/FunctionInfo.cpp
+++ b/llvm/lib/DebugInfo/GSYM/FunctionInfo.cpp
@@ -227,7 +227,7 @@ llvm::Expected<LookupResult> FunctionInfo::lookup(DataExtractor &Data,
     return LR;
   }
 
-  Optional<FileEntry> LineEntryFile = GR.getFile(LineEntry->File);
+  std::optional<FileEntry> LineEntryFile = GR.getFile(LineEntry->File);
   if (!LineEntryFile)
     return createStringError(std::errc::invalid_argument,
                               "failed to extract file[%" PRIu32 "]",
diff --git a/llvm/lib/DebugInfo/GSYM/GsymReader.cpp b/llvm/lib/DebugInfo/GSYM/GsymReader.cpp
index 352af91fa957..6afaeea8f598 100644
--- a/llvm/lib/DebugInfo/GSYM/GsymReader.cpp
+++ b/llvm/lib/DebugInfo/GSYM/GsymReader.cpp
@@ -206,7 +206,7 @@ const Header &GsymReader::getHeader() const {
   return *Hdr;
 }
 
-Optional<uint64_t> GsymReader::getAddress(size_t Index) const {
+std::optional<uint64_t> GsymReader::getAddress(size_t Index) const {
   switch (Hdr->AddrOffSize) {
   case 1: return addressForIndex<uint8_t>(Index);
   case 2: return addressForIndex<uint16_t>(Index);
@@ -216,7 +216,7 @@ Optional<uint64_t> GsymReader::getAddress(size_t Index) const {
   return std::nullopt;
 }
 
-Optional<uint64_t> GsymReader::getAddressInfoOffset(size_t Index) const {
+std::optional<uint64_t> GsymReader::getAddressInfoOffset(size_t Index) const {
   const auto NumAddrInfoOffsets = AddrInfoOffsets.size();
   if (Index < NumAddrInfoOffsets)
     return AddrInfoOffsets[Index];
@@ -227,7 +227,7 @@ Expected<uint64_t>
 GsymReader::getAddressIndex(const uint64_t Addr) const {
   if (Addr >= Hdr->BaseAddress) {
     const uint64_t AddrOffset = Addr - Hdr->BaseAddress;
-    Optional<uint64_t> AddrOffsetIndex;
+    std::optional<uint64_t> AddrOffsetIndex;
     switch (Hdr->AddrOffSize) {
     case 1:
       AddrOffsetIndex = getAddressOffsetIndex<uint8_t>(AddrOffset);
@@ -262,7 +262,7 @@ llvm::Expected<FunctionInfo> GsymReader::getFunctionInfo(uint64_t Addr) const {
   assert(*AddressIndex < AddrInfoOffsets.size());
   auto AddrInfoOffset = AddrInfoOffsets[*AddressIndex];
   DataExtractor Data(MemBuffer->getBuffer().substr(AddrInfoOffset), Endian, 4);
-  if (Optional<uint64_t> OptAddr = getAddress(*AddressIndex)) {
+  if (std::optional<uint64_t> OptAddr = getAddress(*AddressIndex)) {
     auto ExpectedFI = FunctionInfo::decode(Data, *OptAddr);
     if (ExpectedFI) {
       if (ExpectedFI->Range.contains(Addr) || ExpectedFI->Range.size() == 0)
@@ -284,7 +284,7 @@ llvm::Expected<LookupResult> GsymReader::lookup(uint64_t Addr) const {
   assert(*AddressIndex < AddrInfoOffsets.size());
   auto AddrInfoOffset = AddrInfoOffsets[*AddressIndex];
   DataExtractor Data(MemBuffer->getBuffer().substr(AddrInfoOffset), Endian, 4);
-  if (Optional<uint64_t> OptAddr = getAddress(*AddressIndex))
+  if (std::optional<uint64_t> OptAddr = getAddress(*AddressIndex))
     return FunctionInfo::lookup(Data, *this, *OptAddr, Addr);
   return createStringError(std::errc::invalid_argument,
                            "failed to extract address[%" PRIu64 "]",
@@ -382,7 +382,7 @@ void GsymReader::dump(raw_ostream &OS, const InlineInfo &II, uint32_t Indent) {
     dump(OS, ChildII, Indent + 2);
 }
 
-void GsymReader::dump(raw_ostream &OS, Optional<FileEntry> FE) {
+void GsymReader::dump(raw_ostream &OS, std::optional<FileEntry> FE) {
   if (FE) {
     // IF we have the file from index 0, then don't print anything
     if (FE->Dir == 0 && FE->Base == 0)
diff --git a/llvm/lib/DebugInfo/GSYM/InlineInfo.cpp b/llvm/lib/DebugInfo/GSYM/InlineInfo.cpp
index 54cbab88ae3e..f775ab8fb65c 100644
--- a/llvm/lib/DebugInfo/GSYM/InlineInfo.cpp
+++ b/llvm/lib/DebugInfo/GSYM/InlineInfo.cpp
@@ -53,7 +53,8 @@ static bool getInlineStackHelper(const InlineInfo &II, uint64_t Addr,
   return false;
 }
 
-llvm::Optional<InlineInfo::InlineArray> InlineInfo::getInlineStack(uint64_t Addr) const {
+std::optional<InlineInfo::InlineArray>
+InlineInfo::getInlineStack(uint64_t Addr) const {
   InlineArray Result;
   if (getInlineStackHelper(*this, Addr, Result))
     return Result;
@@ -134,7 +135,7 @@ static bool lookup(const GsymReader &GR, DataExtractor &Data, uint64_t &Offset,
       Done = lookup(GR, Data, Offset, ChildBaseAddr, Addr, SrcLocs, Err);
   }
 
-  Optional<FileEntry> CallFile = GR.getFile(Inline.CallFile);
+  std::optional<FileEntry> CallFile = GR.getFile(Inline.CallFile);
   if (!CallFile) {
     Err = createStringError(std::errc::invalid_argument,
                             "failed to extract file[%" PRIu32 "]",
diff --git a/llvm/lib/DebugInfo/LogicalView/Readers/LVELFReader.cpp b/llvm/lib/DebugInfo/LogicalView/Readers/LVELFReader.cpp
index 51ac39fefd3b..37bd53576483 100644
--- a/llvm/lib/DebugInfo/LogicalView/Readers/LVELFReader.cpp
+++ b/llvm/lib/DebugInfo/LogicalView/Readers/LVELFReader.cpp
@@ -398,7 +398,7 @@ void LVELFReader::processOneAttribute(const DWARFDie &Die, LVOffset *OffsetPtr,
       // For toolchains that support the removal of unused code, the linker
       // marks functions that have been removed, by setting the value for the
       // low_pc to the max address.
-      if (Optional<uint64_t> Value = FormValue.getAsAddress()) {
+      if (std::optional<uint64_t> Value = FormValue.getAsAddress()) {
         CurrentLowPC = Value.value();
       } else {
         uint64_t UValue = FormValue.getRawUValue();
@@ -424,10 +424,10 @@ void LVELFReader::processOneAttribute(const DWARFDie &Die, LVOffset *OffsetPtr,
   case dwarf::DW_AT_high_pc:
     if (options().getGeneralCollectRanges()) {
       FoundHighPC = true;
-      if (Optional<uint64_t> Address = FormValue.getAsAddress())
+      if (std::optional<uint64_t> Address = FormValue.getAsAddress())
         // High PC is an address.
         CurrentHighPC = *Address;
-      if (Optional<uint64_t> Offset = FormValue.getAsUnsignedConstant())
+      if (std::optional<uint64_t> Offset = FormValue.getAsUnsignedConstant())
         // High PC is an offset from LowPC.
         CurrentHighPC = CurrentLowPC + *Offset;
       // Store the real upper limit for the address range.
@@ -628,7 +628,7 @@ LVScope *LVELFReader::processOneDie(const DWARFDie &InputDIE, LVScope *Parent,
           !CurrentScope->getLinkageNameIndex() &&
           CurrentScope->getHasReferenceSpecification()) {
         // Get the linkage name in order to search for a possible comdat.
-        Optional<DWARFFormValue> LinkageDIE =
+        std::optional<DWARFFormValue> LinkageDIE =
             DIE.findRecursively(dwarf::DW_AT_linkage_name);
         if (LinkageDIE.has_value()) {
           StringRef Name(dwarf::toStringRef(LinkageDIE));
@@ -899,7 +899,7 @@ Error LVELFReader::createScopes() {
     DWARFDie UnitDie = CU->getUnitDIE();
     SmallString<16> DWOAlternativeLocation;
     if (UnitDie) {
-      Optional<const char *> DWOFileName =
+      std::optional<const char *> DWOFileName =
           CU->getVersion() >= 5
               ? dwarf::toString(UnitDie.find(dwarf::DW_AT_dwo_name))
               : dwarf::toString(UnitDie.find(dwarf::DW_AT_GNU_dwo_name));
@@ -1002,13 +1002,13 @@ void LVELFReader::processLocationList(dwarf::Attribute Attr,
       FormValue.isFormClass(DWARFFormValue::FC_SectionOffset)) {
     uint64_t Offset = *FormValue.getAsSectionOffset();
     if (FormValue.getForm() == dwarf::DW_FORM_loclistx) {
-      Optional<uint64_t> LoclistOffset = U->getLoclistOffset(Offset);
+      std::optional<uint64_t> LoclistOffset = U->getLoclistOffset(Offset);
       if (!LoclistOffset)
         return;
       Offset = *LoclistOffset;
     }
     uint64_t BaseAddr = 0;
-    if (Optional<SectionedAddress> BA = U->getBaseAddress())
+    if (std::optional<SectionedAddress> BA = U->getBaseAddress())
       BaseAddr = BA->Address;
     LVAddress LowPC = 0;
     LVAddress HighPC = 0;
diff --git a/llvm/lib/DebugInfo/PDB/DIA/DIADataStream.cpp b/llvm/lib/DebugInfo/PDB/DIA/DIADataStream.cpp
index 247406c49efc..ee4078a20b72 100644
--- a/llvm/lib/DebugInfo/PDB/DIA/DIADataStream.cpp
+++ b/llvm/lib/DebugInfo/PDB/DIA/DIADataStream.cpp
@@ -24,7 +24,7 @@ std::string DIADataStream::getName() const {
   return invokeBstrMethod(*StreamData, &IDiaEnumDebugStreamData::get_name);
 }
 
-llvm::Optional<DIADataStream::RecordType>
+std::optional<DIADataStream::RecordType>
 DIADataStream::getItemAtIndex(uint32_t Index) const {
   RecordType Record;
   DWORD RecordSize = 0;
diff --git a/llvm/lib/DebugInfo/PDB/Native/DbiStreamBuilder.cpp b/llvm/lib/DebugInfo/PDB/Native/DbiStreamBuilder.cpp
index 3a719bd07c8a..fdb8c1bf2ad5 100644
--- a/llvm/lib/DebugInfo/PDB/Native/DbiStreamBuilder.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/DbiStreamBuilder.cpp
@@ -86,7 +86,7 @@ Error DbiStreamBuilder::addDbgStream(pdb::DbgHeaderType Type,
   assert(Type != DbgHeaderType::NewFPO &&
          "NewFPO data should be written via addFrameData()!");
 
-  DbgStreams[(int)Type].emplace();
+  DbgStreams[(int)Type] = DebugStream{};
   DbgStreams[(int)Type]->Size = Data.size();
   DbgStreams[(int)Type]->WriteFn = [Data](BinaryStreamWriter &Writer) {
     return Writer.writeArray(Data);
@@ -286,7 +286,7 @@ Error DbiStreamBuilder::finalize() {
 
 Error DbiStreamBuilder::finalizeMsfLayout() {
   if (NewFpoData) {
-    DbgStreams[(int)DbgHeaderType::NewFPO].emplace();
+    DbgStreams[(int)DbgHeaderType::NewFPO] = DebugStream{};
     DbgStreams[(int)DbgHeaderType::NewFPO]->Size =
         NewFpoData->calculateSerializedSize();
     DbgStreams[(int)DbgHeaderType::NewFPO]->WriteFn =
@@ -296,7 +296,7 @@ Error DbiStreamBuilder::finalizeMsfLayout() {
   }
 
   if (!OldFpoData.empty()) {
-    DbgStreams[(int)DbgHeaderType::FPO].emplace();
+    DbgStreams[(int)DbgHeaderType::FPO] = DebugStream{};
     DbgStreams[(int)DbgHeaderType::FPO]->Size =
         sizeof(object::FpoData) * OldFpoData.size();
     DbgStreams[(int)DbgHeaderType::FPO]->WriteFn =
diff --git a/llvm/lib/DebugInfo/PDB/Native/NativeEnumTypes.cpp b/llvm/lib/DebugInfo/PDB/Native/NativeEnumTypes.cpp
index 6912b8dc838e..2c3b19c7e567 100644
--- a/llvm/lib/DebugInfo/PDB/Native/NativeEnumTypes.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/NativeEnumTypes.cpp
@@ -27,7 +27,7 @@ NativeEnumTypes::NativeEnumTypes(NativeSession &PDBSession,
                                  LazyRandomTypeCollection &Types,
                                  std::vector<codeview::TypeLeafKind> Kinds)
     : Index(0), Session(PDBSession) {
-  Optional<TypeIndex> TI = Types.getFirst();
+  std::optional<TypeIndex> TI = Types.getFirst();
   while (TI) {
     CVType CVT = Types.getType(*TI);
     TypeLeafKind K = CVT.kind();
diff --git a/llvm/lib/DebugInfo/PDB/Native/NativeInlineSiteSymbol.cpp b/llvm/lib/DebugInfo/PDB/Native/NativeInlineSiteSymbol.cpp
index 7eede122f669..dba00b451ef6 100644
--- a/llvm/lib/DebugInfo/PDB/Native/NativeInlineSiteSymbol.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/NativeInlineSiteSymbol.cpp
@@ -40,7 +40,7 @@ void NativeInlineSiteSymbol::dump(raw_ostream &OS, int Indent,
   dumpSymbolField(OS, "name", getName(), Indent);
 }
 
-static Optional<InlineeSourceLine>
+static std::optional<InlineeSourceLine>
 findInlineeByTypeIndex(TypeIndex Id, ModuleDebugStreamRef &ModS) {
   for (const auto &SS : ModS.getSubsectionsArray()) {
     if (SS.kind() != DebugSubsectionKind::InlineeLines)
@@ -104,11 +104,11 @@ void NativeInlineSiteSymbol::getLineOffset(uint32_t OffsetInFunc,
   LineOffset = 0;
   FileOffset = 0;
   uint32_t CodeOffset = 0;
-  Optional<uint32_t> CodeOffsetBase;
-  Optional<uint32_t> CodeOffsetEnd;
-  Optional<int32_t> CurLineOffset;
-  Optional<int32_t> NextLineOffset;
-  Optional<uint32_t> NextFileOffset;
+  std::optional<uint32_t> CodeOffsetBase;
+  std::optional<uint32_t> CodeOffsetEnd;
+  std::optional<int32_t> CurLineOffset;
+  std::optional<int32_t> NextLineOffset;
+  std::optional<uint32_t> NextFileOffset;
   auto UpdateCodeOffset = [&](uint32_t Delta) {
     if (!CodeOffsetBase)
       CodeOffsetBase = CodeOffset;
@@ -209,7 +209,7 @@ NativeInlineSiteSymbol::findInlineeLinesByVA(uint64_t VA,
   getLineOffset(VA - ParentAddr, SrcLineOffset, SrcFileOffset);
 
   // Get line info from inlinee line table.
-  Optional<InlineeSourceLine> Inlinee =
+  std::optional<InlineeSourceLine> Inlinee =
       findInlineeByTypeIndex(Sym.Inlinee, ModS.get());
 
   if (!Inlinee)
diff --git a/llvm/lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp b/llvm/lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp
index 641043a8e186..27df769ee6f2 100644
--- a/llvm/lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp
@@ -354,7 +354,7 @@ Error PDBFileBuilder::commit(StringRef Filename, codeview::GUID *Guid) {
   } else {
     H->Age = Info->getAge();
     H->Guid = Info->getGuid();
-    Optional<uint32_t> Sig = Info->getSignature();
+    std::optional<uint32_t> Sig = Info->getSignature();
     H->Signature = Sig ? *Sig : time(nullptr);
   }
 
diff --git a/llvm/lib/DebugInfo/PDB/Native/TpiStreamBuilder.cpp b/llvm/lib/DebugInfo/PDB/Native/TpiStreamBuilder.cpp
index 986e45e050c7..1c94194de3a2 100644
--- a/llvm/lib/DebugInfo/PDB/Native/TpiStreamBuilder.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/TpiStreamBuilder.cpp
@@ -55,7 +55,7 @@ void TpiStreamBuilder::updateTypeIndexOffsets(ArrayRef<uint16_t> Sizes) {
 }
 
 void TpiStreamBuilder::addTypeRecord(ArrayRef<uint8_t> Record,
-                                     Optional<uint32_t> Hash) {
+                                     std::optional<uint32_t> Hash) {
   assert(((Record.size() & 3) == 0) &&
          "The type record's size is not a multiple of 4 bytes which will "
          "cause misalignment in the output TPI stream!");
diff --git a/llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp b/llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp
index 8557c755c5f7..bfd6f7c02ca3 100644
--- a/llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp
+++ b/llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp
@@ -31,8 +31,8 @@ namespace symbolize {
 class SourceCode {
   std::unique_ptr<MemoryBuffer> MemBuf;
 
-  Optional<StringRef> load(StringRef FileName,
-                           const Optional<StringRef> &EmbeddedSource) {
+  std::optional<StringRef>
+  load(StringRef FileName, const std::optional<StringRef> &EmbeddedSource) {
     if (Lines <= 0)
       return std::nullopt;
 
@@ -48,7 +48,7 @@ class SourceCode {
     }
   }
 
-  Optional<StringRef> pruneSource(const Optional<StringRef> &Source) {
+  std::optional<StringRef> pruneSource(const std::optional<StringRef> &Source) {
     if (!Source)
       return std::nullopt;
     size_t FirstLinePos = StringRef::npos, Pos = 0;
@@ -71,11 +71,11 @@ public:
   const int Lines;
   const int64_t FirstLine;
   const int64_t LastLine;
-  const Optional<StringRef> PrunedSource;
+  const std::optional<StringRef> PrunedSource;
 
-  SourceCode(
-      StringRef FileName, int64_t Line, int Lines,
-      const Optional<StringRef> &EmbeddedSource = Optional<StringRef>())
+  SourceCode(StringRef FileName, int64_t Line, int Lines,
+             const std::optional<StringRef> &EmbeddedSource =
+                 std::optional<StringRef>())
       : Line(Line), Lines(Lines),
         FirstLine(std::max(static_cast<int64_t>(1), Line - Lines / 2)),
         LastLine(FirstLine + Lines - 1),
diff --git a/llvm/lib/DebugInfo/Symbolize/Markup.cpp b/llvm/lib/DebugInfo/Symbolize/Markup.cpp
index a6541162f468..ae3e24c0d500 100644
--- a/llvm/lib/DebugInfo/Symbolize/Markup.cpp
+++ b/llvm/lib/DebugInfo/Symbolize/Markup.cpp
@@ -42,7 +42,7 @@ void MarkupParser::parseLine(StringRef Line) {
   this->Line = Line;
 }
 
-Optional<MarkupNode> MarkupParser::nextNode() {
+std::optional<MarkupNode> MarkupParser::nextNode() {
   // Pull something out of the buffer if possible.
   if (!Buffer.empty()) {
     if (NextIdx < Buffer.size())
@@ -57,7 +57,7 @@ Optional<MarkupNode> MarkupParser::nextNode() {
     return std::nullopt;
 
   if (!InProgressMultiline.empty()) {
-    if (Optional<StringRef> MultilineEnd = parseMultiLineEnd(Line)) {
+    if (std::optional<StringRef> MultilineEnd = parseMultiLineEnd(Line)) {
       llvm::append_range(InProgressMultiline, *MultilineEnd);
       assert(FinishedMultiline.empty() &&
              "At most one multi-line element can be finished at a time.");
@@ -74,7 +74,7 @@ Optional<MarkupNode> MarkupParser::nextNode() {
   }
 
   // Find the first valid markup element, if any.
-  if (Optional<MarkupNode> Element = parseElement(Line)) {
+  if (std::optional<MarkupNode> Element = parseElement(Line)) {
     parseTextOutsideMarkup(takeTo(Line, Element->Text.begin()));
     Buffer.push_back(std::move(*Element));
     advanceTo(Line, Element->Text.end());
@@ -83,7 +83,7 @@ Optional<MarkupNode> MarkupParser::nextNode() {
 
   // Since there were no valid elements remaining, see if the line opens a
   // multi-line element.
-  if (Optional<StringRef> MultilineBegin = parseMultiLineBegin(Line)) {
+  if (std::optional<StringRef> MultilineBegin = parseMultiLineBegin(Line)) {
     // Emit any text before the element.
     parseTextOutsideMarkup(takeTo(Line, MultilineBegin->begin()));
 
@@ -111,7 +111,7 @@ void MarkupParser::flush() {
 
 // Finds and returns the next valid markup element in the given line. Returns
 // None if the line contains no valid elements.
-Optional<MarkupNode> MarkupParser::parseElement(StringRef Line) {
+std::optional<MarkupNode> MarkupParser::parseElement(StringRef Line) {
   while (true) {
     // Find next element using begin and end markers.
     size_t BeginPos = Line.find("{{{");
@@ -169,7 +169,7 @@ void MarkupParser::parseTextOutsideMarkup(StringRef Text) {
 
 // Given that a line doesn't contain any valid markup, see if it ends with the
 // start of a multi-line element. If so, returns the beginning.
-Optional<StringRef> MarkupParser::parseMultiLineBegin(StringRef Line) {
+std::optional<StringRef> MarkupParser::parseMultiLineBegin(StringRef Line) {
   // A multi-line begin marker must be the last one on the line.
   size_t BeginPos = Line.rfind("{{{");
   if (BeginPos == StringRef::npos)
@@ -194,7 +194,7 @@ Optional<StringRef> MarkupParser::parseMultiLineBegin(StringRef Line) {
 
 // See if the line begins with the ending of an in-progress multi-line element.
 // If so, return the ending.
-Optional<StringRef> MarkupParser::parseMultiLineEnd(StringRef Line) {
+std::optional<StringRef> MarkupParser::parseMultiLineEnd(StringRef Line) {
   size_t EndPos = Line.find("}}}");
   if (EndPos == StringRef::npos)
     return std::nullopt;
diff --git a/llvm/lib/DebugInfo/Symbolize/MarkupFilter.cpp b/llvm/lib/DebugInfo/Symbolize/MarkupFilter.cpp
index c3b1e4d5b271..86fa52654a02 100644
--- a/llvm/lib/DebugInfo/Symbolize/MarkupFilter.cpp
+++ b/llvm/lib/DebugInfo/Symbolize/MarkupFilter.cpp
@@ -37,7 +37,7 @@ using namespace llvm;
 using namespace llvm::symbolize;
 
 MarkupFilter::MarkupFilter(raw_ostream &OS, LLVMSymbolizer &Symbolizer,
-                           Optional<bool> ColorsEnabled)
+                           std::optional<bool> ColorsEnabled)
     : OS(OS), Symbolizer(Symbolizer),
       ColorsEnabled(
           ColorsEnabled.value_or(WithColor::defaultAutoDetectFunction()(OS))) {}
@@ -51,7 +51,7 @@ void MarkupFilter::filter(StringRef Line) {
   // See if the line is a contextual (i.e. contains a contextual element).
   // In this case, anything after the contextual element is elided, or the whole
   // line may be elided.
-  while (Optional<MarkupNode> Node = Parser.nextNode()) {
+  while (std::optional<MarkupNode> Node = Parser.nextNode()) {
     // If this was a contextual line, then summarily stop processing.
     if (tryContextualElement(*Node, DeferredNodes))
       return;
@@ -67,7 +67,7 @@ void MarkupFilter::filter(StringRef Line) {
 
 void MarkupFilter::finish() {
   Parser.flush();
-  while (Optional<MarkupNode> Node = Parser.nextNode())
+  while (std::optional<MarkupNode> Node = Parser.nextNode())
     filterNode(*Node);
   endAnyModuleInfoLine();
   resetColor();
@@ -96,7 +96,7 @@ bool MarkupFilter::tryMMap(const MarkupNode &Node,
                            const SmallVector<MarkupNode> &DeferredNodes) {
   if (Node.Tag != "mmap")
     return false;
-  Optional<MMap> ParsedMMap = parseMMap(Node);
+  std::optional<MMap> ParsedMMap = parseMMap(Node);
   if (!ParsedMMap)
     return true;
 
@@ -148,7 +148,7 @@ bool MarkupFilter::tryModule(const MarkupNode &Node,
                              const SmallVector<MarkupNode> &DeferredNodes) {
   if (Node.Tag != "module")
     return false;
-  Optional<Module> ParsedModule = parseModule(Node);
+  std::optional<Module> ParsedModule = parseModule(Node);
   if (!ParsedModule)
     return true;
 
@@ -243,7 +243,7 @@ bool MarkupFilter::tryPC(const MarkupNode &Node) {
   if (!checkNumFieldsAtMost(Node, 2))
     return true;
 
-  Optional<uint64_t> Addr = parseAddr(Node.Fields[0]);
+  std::optional<uint64_t> Addr = parseAddr(Node.Fields[0]);
   if (!Addr)
     return true;
 
@@ -251,7 +251,7 @@ bool MarkupFilter::tryPC(const MarkupNode &Node) {
   // locations.
   PCType Type = PCType::PreciseCode;
   if (Node.Fields.size() == 2) {
-    Optional<PCType> ParsedType = parsePCType(Node.Fields[1]);
+    std::optional<PCType> ParsedType = parsePCType(Node.Fields[1]);
     if (!ParsedType)
       return true;
     Type = *ParsedType;
@@ -297,18 +297,18 @@ bool MarkupFilter::tryBackTrace(const MarkupNode &Node) {
   if (!checkNumFieldsAtMost(Node, 3))
     return true;
 
-  Optional<uint64_t> FrameNumber = parseFrameNumber(Node.Fields[0]);
+  std::optional<uint64_t> FrameNumber = parseFrameNumber(Node.Fields[0]);
   if (!FrameNumber)
     return true;
 
-  Optional<uint64_t> Addr = parseAddr(Node.Fields[1]);
+  std::optional<uint64_t> Addr = parseAddr(Node.Fields[1]);
   if (!Addr)
     return true;
 
   // Backtrace addresses are assumed to be return addresses by default.
   PCType Type = PCType::ReturnAddress;
   if (Node.Fields.size() == 3) {
-    Optional<PCType> ParsedType = parsePCType(Node.Fields[2]);
+    std::optional<PCType> ParsedType = parsePCType(Node.Fields[2]);
     if (!ParsedType)
       return true;
     Type = *ParsedType;
@@ -375,7 +375,7 @@ bool MarkupFilter::tryData(const MarkupNode &Node) {
     return false;
   if (!checkNumFields(Node, 1))
     return true;
-  Optional<uint64_t> Addr = parseAddr(Node.Fields[0]);
+  std::optional<uint64_t> Addr = parseAddr(Node.Fields[0]);
   if (!Addr)
     return true;
 
@@ -499,7 +499,7 @@ void MarkupFilter::printValue(Twine Value) {
     return std::nullopt;                                                       \
   TYPE NAME = std::move(*NAME##Opt)
 
-Optional<MarkupFilter::Module>
+std::optional<MarkupFilter::Module>
 MarkupFilter::parseModule(const MarkupNode &Element) const {
   if (!checkNumFieldsAtLeast(Element, 3))
     return std::nullopt;
@@ -518,7 +518,7 @@ MarkupFilter::parseModule(const MarkupNode &Element) const {
   return Module{ID, Name.str(), std::move(BuildID)};
 }
 
-Optional<MarkupFilter::MMap>
+std::optional<MarkupFilter::MMap>
 MarkupFilter::parseMMap(const MarkupNode &Element) const {
   if (!checkNumFieldsAtLeast(Element, 3))
     return std::nullopt;
@@ -547,7 +547,7 @@ MarkupFilter::parseMMap(const MarkupNode &Element) const {
 }
 
 // Parse an address (%p in the spec).
-Optional<uint64_t> MarkupFilter::parseAddr(StringRef Str) const {
+std::optional<uint64_t> MarkupFilter::parseAddr(StringRef Str) const {
   if (Str.empty()) {
     reportTypeError(Str, "address");
     return std::nullopt;
@@ -567,7 +567,7 @@ Optional<uint64_t> MarkupFilter::parseAddr(StringRef Str) const {
 }
 
 // Parse a module ID (%i in the spec).
-Optional<uint64_t> MarkupFilter::parseModuleID(StringRef Str) const {
+std::optional<uint64_t> MarkupFilter::parseModuleID(StringRef Str) const {
   uint64_t ID;
   if (Str.getAsInteger(0, ID)) {
     reportTypeError(Str, "module ID");
@@ -577,7 +577,7 @@ Optional<uint64_t> MarkupFilter::parseModuleID(StringRef Str) const {
 }
 
 // Parse a size (%i in the spec).
-Optional<uint64_t> MarkupFilter::parseSize(StringRef Str) const {
+std::optional<uint64_t> MarkupFilter::parseSize(StringRef Str) const {
   uint64_t ID;
   if (Str.getAsInteger(0, ID)) {
     reportTypeError(Str, "size");
@@ -587,7 +587,7 @@ Optional<uint64_t> MarkupFilter::parseSize(StringRef Str) const {
 }
 
 // Parse a frame number (%i in the spec).
-Optional<uint64_t> MarkupFilter::parseFrameNumber(StringRef Str) const {
+std::optional<uint64_t> MarkupFilter::parseFrameNumber(StringRef Str) const {
   uint64_t ID;
   if (Str.getAsInteger(10, ID)) {
     reportTypeError(Str, "frame number");
@@ -597,7 +597,8 @@ Optional<uint64_t> MarkupFilter::parseFrameNumber(StringRef Str) const {
 }
 
 // Parse a build ID (%x in the spec).
-Optional<SmallVector<uint8_t>> MarkupFilter::parseBuildID(StringRef Str) const {
+std::optional<SmallVector<uint8_t>>
+MarkupFilter::parseBuildID(StringRef Str) const {
   std::string Bytes;
   if (Str.empty() || Str.size() % 2 || !tryGetFromHex(Str, Bytes)) {
     reportTypeError(Str, "build ID");
@@ -609,7 +610,7 @@ Optional<SmallVector<uint8_t>> MarkupFilter::parseBuildID(StringRef Str) const {
 }
 
 // Parses the mode string for an mmap element.
-Optional<std::string> MarkupFilter::parseMode(StringRef Str) const {
+std::optional<std::string> MarkupFilter::parseMode(StringRef Str) const {
   if (Str.empty()) {
     reportTypeError(Str, "mode");
     return std::nullopt;
@@ -634,9 +635,10 @@ Optional<std::string> MarkupFilter::parseMode(StringRef Str) const {
   return Str.lower();
 }
 
-Optional<MarkupFilter::PCType> MarkupFilter::parsePCType(StringRef Str) const {
-  Optional<MarkupFilter::PCType> Type =
-      StringSwitch<Optional<MarkupFilter::PCType>>(Str)
+std::optional<MarkupFilter::PCType>
+MarkupFilter::parsePCType(StringRef Str) const {
+  std::optional<MarkupFilter::PCType> Type =
+      StringSwitch<std::optional<MarkupFilter::PCType>>(Str)
           .Case("ra", MarkupFilter::PCType::ReturnAddress)
           .Case("pc", MarkupFilter::PCType::PreciseCode)
           .Default(std::nullopt);
diff --git a/llvm/lib/ProfileData/InstrProfCorrelator.cpp b/llvm/lib/ProfileData/InstrProfCorrelator.cpp
index 6c460a5f9c31..38ae5d8f821c 100644
--- a/llvm/lib/ProfileData/InstrProfCorrelator.cpp
+++ b/llvm/lib/ProfileData/InstrProfCorrelator.cpp
@@ -264,11 +264,11 @@ void DwarfInstrProfCorrelator<IntPtrT>::correlateProfileDataImpl(
     if (!isDIEOfProbe(Die))
       return;
     Optional<const char *> FunctionName;
-    Optional<uint64_t> CFGHash;
+    std::optional<uint64_t> CFGHash;
     Optional<uint64_t> CounterPtr = getLocation(Die);
     auto FnDie = Die.getParent();
     auto FunctionPtr = dwarf::toAddress(FnDie.find(dwarf::DW_AT_low_pc));
-    Optional<uint64_t> NumCounters;
+    std::optional<uint64_t> NumCounters;
     for (const DWARFDie &Child : Die.children()) {
       if (Child.getTag() != dwarf::DW_TAG_LLVM_annotation)
         continue;
diff --git a/llvm/tools/dsymutil/DwarfLinkerForBinary.cpp b/llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
index ac140338020a..d4fa73fc0f9a 100644
--- a/llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
+++ b/llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
@@ -980,7 +980,7 @@ bool DwarfLinkerForBinary::AddressManager::isLiveVariable(
     const DWARFDie &DIE, CompileUnit::DIEInfo &MyInfo) {
   const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
 
-  Optional<uint32_t> LocationIdx =
+  std::optional<uint32_t> LocationIdx =
       Abbrev->findAttributeIndex(dwarf::DW_AT_location);
   if (!LocationIdx)
     return false;
@@ -999,7 +999,8 @@ bool DwarfLinkerForBinary::AddressManager::isLiveSubprogram(
     const DWARFDie &DIE, CompileUnit::DIEInfo &MyInfo) {
   const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
 
-  Optional<uint32_t> LowPcIdx = Abbrev->findAttributeIndex(dwarf::DW_AT_low_pc);
+  std::optional<uint32_t> LowPcIdx =
+      Abbrev->findAttributeIndex(dwarf::DW_AT_low_pc);
   if (!LowPcIdx)
     return false;
 
@@ -1015,8 +1016,8 @@ bool DwarfLinkerForBinary::AddressManager::isLiveSubprogram(
   }
 
   if (Form == dwarf::DW_FORM_addrx) {
-    Optional<DWARFFormValue> AddrValue = DIE.find(dwarf::DW_AT_low_pc);
-    if (Optional<uint64_t> AddrOffsetSectionBase =
+    std::optional<DWARFFormValue> AddrValue = DIE.find(dwarf::DW_AT_low_pc);
+    if (std::optional<uint64_t> AddrOffsetSectionBase =
             DIE.getDwarfUnit()->getAddrOffsetSectionBase()) {
       uint64_t StartOffset = *AddrOffsetSectionBase + AddrValue->getRawUValue();
       uint64_t EndOffset =
diff --git a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
index cc7f353330b1..59e736183e57 100644
--- a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
+++ b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
@@ -137,8 +137,7 @@ static alias DumpAllAlias("a", desc("Alias for --all"), aliasopt(DumpAll),
 
 // Options for dumping specific sections.
 static unsigned DumpType = DIDT_Null;
-static std::array<llvm::Optional<uint64_t>, (unsigned)DIDT_ID_Count>
-    DumpOffsets;
+static std::array<std::optional<uint64_t>, (unsigned)DIDT_ID_Count> DumpOffsets;
 #define HANDLE_DWARF_SECTION(ENUM_NAME, ELF_NAME, CMDLINE_NAME, OPTION)        \
   static opt<OPTION> Dump##ENUM_NAME(CMDLINE_NAME,                             \
                                      desc("Dump the " ELF_NAME " section"),    \
@@ -386,7 +385,7 @@ static void filterByName(const StringSet<> &Names,
 static void getDies(DWARFContext &DICtx, const AppleAcceleratorTable &Accel,
                     StringRef Name, SmallVectorImpl<DWARFDie> &Dies) {
   for (const auto &Entry : Accel.equal_range(Name)) {
-    if (llvm::Optional<uint64_t> Off = Entry.getDIESectionOffset()) {
+    if (std::optional<uint64_t> Off = Entry.getDIESectionOffset()) {
       if (DWARFDie Die = DICtx.getDIEForOffset(*Off))
         Dies.push_back(Die);
     }
@@ -395,8 +394,8 @@ static void getDies(DWARFContext &DICtx, const AppleAcceleratorTable &Accel,
 
 static DWARFDie toDie(const DWARFDebugNames::Entry &Entry,
                       DWARFContext &DICtx) {
-  llvm::Optional<uint64_t> CUOff = Entry.getCUOffset();
-  llvm::Optional<uint64_t> Off = Entry.getDIEUnitOffset();
+  std::optional<uint64_t> CUOff = Entry.getCUOffset();
+  std::optional<uint64_t> Off = Entry.getDIEUnitOffset();
   if (!CUOff || !Off)
     return DWARFDie();
 
@@ -404,7 +403,7 @@ static DWARFDie toDie(const DWARFDebugNames::Entry &Entry,
   if (!CU)
     return DWARFDie();
 
-  if (llvm::Optional<uint64_t> DWOId = CU->getDWOId()) {
+  if (std::optional<uint64_t> DWOId = CU->getDWOId()) {
     // This is a skeleton unit. Look up the DIE in the DWO unit.
     CU = DICtx.getDWOCompileUnitForHash(*DWOId);
     if (!CU)
@@ -477,7 +476,7 @@ static bool collectLineTableSources(const DWARFDebugLine::LineTable &LT,
                                     StringRef CompDir,
                                     std::vector<std::string> &Sources) {
   bool Result = true;
-  llvm::Optional<uint64_t> LastIndex = LT.getLastValidFileIndex();
+  std::optional<uint64_t> LastIndex = LT.getLastValidFileIndex();
   for (uint64_t I = LT.hasFileAtIndex(0) ? 0 : 1,
                 E = LastIndex ? *LastIndex + 1 : 0;
        I < E; ++I) {
diff --git a/llvm/tools/llvm-dwarfutil/DebugInfoLinker.cpp b/llvm/tools/llvm-dwarfutil/DebugInfoLinker.cpp
index f06d8d038f65..48d3b1fcc3f7 100644
--- a/llvm/tools/llvm-dwarfutil/DebugInfoLinker.cpp
+++ b/llvm/tools/llvm-dwarfutil/DebugInfoLinker.cpp
@@ -76,7 +76,7 @@ public:
             DIE.getTag() == dwarf::DW_TAG_label) &&
            "Wrong type of input die");
 
-    if (Optional<uint64_t> LowPC =
+    if (std::optional<uint64_t> LowPC =
             dwarf::toAddress(DIE.find(dwarf::DW_AT_low_pc))) {
       if (!isDeadAddress(*LowPC, DIE.getDwarfUnit()->getVersion(),
                          Opts.Tombstone,
diff --git a/llvm/tools/llvm-pdbutil/DumpOutputStyle.cpp b/llvm/tools/llvm-pdbutil/DumpOutputStyle.cpp
index a173eb1faa62..4b604206fc98 100644
--- a/llvm/tools/llvm-pdbutil/DumpOutputStyle.cpp
+++ b/llvm/tools/llvm-pdbutil/DumpOutputStyle.cpp
@@ -602,7 +602,8 @@ Error DumpOutputStyle::dumpTypeStats() {
   StatCollection TypeStats;
   LazyRandomTypeCollection &Types =
       opts::dump::DumpTypeStats ? File.types() : File.ids();
-  for (Optional<TypeIndex> TI = Types.getFirst(); TI; TI = Types.getNext(*TI)) {
+  for (std::optional<TypeIndex> TI = Types.getFirst(); TI;
+       TI = Types.getNext(*TI)) {
     CVType Type = Types.getType(*TI);
     TypeStats.update(uint32_t(Type.kind()), Type.length());
   }
@@ -692,7 +693,7 @@ Error DumpOutputStyle::dumpUdtStats() {
       Kind = kNoneUdtKind;
     else if (UDT.Type.isSimple())
       Kind = kSimpleUdtKind;
-    else if (Optional<CVType> T = TpiTypes.tryGetType(UDT.Type)) {
+    else if (std::optional<CVType> T = TpiTypes.tryGetType(UDT.Type)) {
       Kind = T->kind();
       RecordSize = T->length();
     } else
@@ -1250,7 +1251,7 @@ static void dumpPartialTypeStream(LinePrinter &Printer,
       if (TI.isSimple()) {
         Printer.formatLine("{0} | {1}", fmt_align(I, AlignStyle::Right, Width),
                            Types.getTypeName(TI));
-      } else if (Optional<CVType> Type = Types.tryGetType(TI)) {
+      } else if (std::optional<CVType> Type = Types.tryGetType(TI)) {
         if (auto EC = codeview::visitTypeRecord(*Type, TI, V))
           Printer.formatLine("An error occurred dumping type record {0}: {1}",
                              TI, toString(std::move(EC)));
@@ -1517,7 +1518,8 @@ Error DumpOutputStyle::dumpTypeRefStats() {
   size_t TotalBytes = 0;
   size_t RefBytes = 0;
   auto &Types = File.types();
-  for (Optional<TypeIndex> TI = Types.getFirst(); TI; TI = Types.getNext(*TI)) {
+  for (std::optional<TypeIndex> TI = Types.getFirst(); TI;
+       TI = Types.getNext(*TI)) {
     CVType Type = File.types().getType(*TI);
     TotalBytes += Type.length();
     if (RefTracker->isTypeReferenced(*TI)) {
diff --git a/llvm/tools/llvm-pdbutil/TypeReferenceTracker.cpp b/llvm/tools/llvm-pdbutil/TypeReferenceTracker.cpp
index d813bc22a93c..5ae720aace42 100644
--- a/llvm/tools/llvm-pdbutil/TypeReferenceTracker.cpp
+++ b/llvm/tools/llvm-pdbutil/TypeReferenceTracker.cpp
@@ -24,7 +24,8 @@ using namespace llvm::codeview;
 // just iterate up front to find out.
 static uint32_t getNumRecordsInCollection(LazyRandomTypeCollection &Types) {
   uint32_t NumTypes = 0;
-  for (Optional<TypeIndex> TI = Types.getFirst(); TI; TI = Types.getNext(*TI))
+  for (std::optional<TypeIndex> TI = Types.getFirst(); TI;
+       TI = Types.getNext(*TI))
     ++NumTypes;
   return NumTypes;
 }
@@ -129,9 +130,9 @@ void TypeReferenceTracker::markReferencedTypes() {
     TiRefKind RefKind;
     TypeIndex RefTI;
     std::tie(RefKind, RefTI) = RefWorklist.pop_back_val();
-    Optional<CVType> Rec = (Ids && RefKind == TiRefKind::IndexRef)
-                               ? Ids->tryGetType(RefTI)
-                               : Types.tryGetType(RefTI);
+    std::optional<CVType> Rec = (Ids && RefKind == TiRefKind::IndexRef)
+                                    ? Ids->tryGetType(RefTI)
+                                    : Types.tryGetType(RefTI);
     if (!Rec)
       continue; // FIXME: Report a reference to a non-existant type.
 
diff --git a/llvm/tools/llvm-profgen/ProfiledBinary.cpp b/llvm/tools/llvm-profgen/ProfiledBinary.cpp
index 1de06f96eff3..3d549f742ddb 100644
--- a/llvm/tools/llvm-profgen/ProfiledBinary.cpp
+++ b/llvm/tools/llvm-profgen/ProfiledBinary.cpp
@@ -760,7 +760,7 @@ void ProfiledBinary::loadSymbolsFromDWARF(ObjectFile &Obj) {
   // Handles DWO sections that can either be in .o, .dwo or .dwp files.
   for (const auto &CompilationUnit : DebugContext->compile_units()) {
     DWARFUnit *const DwarfUnit = CompilationUnit.get();
-    if (llvm::Optional<uint64_t> DWOId = DwarfUnit->getDWOId()) {
+    if (std::optional<uint64_t> DWOId = DwarfUnit->getDWOId()) {
       DWARFUnit *DWOCU = DwarfUnit->getNonSkeletonUnitDIE(false).getDwarfUnit();
       if (!DWOCU->isDWOUnit()) {
         std::string DWOName = dwarf::toString(
diff --git a/llvm/tools/llvm-readobj/COFFDumper.cpp b/llvm/tools/llvm-readobj/COFFDumper.cpp
index 19c9830c0562..eed1e948dbcb 100644
--- a/llvm/tools/llvm-readobj/COFFDumper.cpp
+++ b/llvm/tools/llvm-readobj/COFFDumper.cpp
@@ -1371,7 +1371,7 @@ void COFFDumper::mergeCodeViewTypes(MergingTypeTableBuilder &CVIDs,
                     Obj->getFileName());
       }
       SmallVector<TypeIndex, 128> SourceToDest;
-      Optional<PCHMergerInfo> PCHInfo;
+      std::optional<PCHMergerInfo> PCHInfo;
       if (GHash) {
         std::vector<GloballyHashedType> Hashes =
             GloballyHashedType::hashTypes(Types);
diff --git a/llvm/tools/llvm-symbolizer/llvm-symbolizer.cpp b/llvm/tools/llvm-symbolizer/llvm-symbolizer.cpp
index 73750c269026..5a74dfb56eee 100644
--- a/llvm/tools/llvm-symbolizer/llvm-symbolizer.cpp
+++ b/llvm/tools/llvm-symbolizer/llvm-symbolizer.cpp
@@ -341,11 +341,11 @@ static FunctionNameKind decideHowToPrintFunctions(const opt::InputArgList &Args,
   return IsAddr2Line ? FunctionNameKind::None : FunctionNameKind::LinkageName;
 }
 
-static Optional<bool> parseColorArg(const opt::InputArgList &Args) {
+static std::optional<bool> parseColorArg(const opt::InputArgList &Args) {
   if (Args.hasArg(OPT_color))
     return true;
   if (const opt::Arg *A = Args.getLastArg(OPT_color_EQ))
-    return StringSwitch<Optional<bool>>(A->getValue())
+    return StringSwitch<std::optional<bool>>(A->getValue())
         .Case("always", true)
         .Case("never", false)
         .Case("auto", std::nullopt);
diff --git a/llvm/unittests/BinaryFormat/DwarfTest.cpp b/llvm/unittests/BinaryFormat/DwarfTest.cpp
index ddafbb4102bd..2fff8657939b 100644
--- a/llvm/unittests/BinaryFormat/DwarfTest.cpp
+++ b/llvm/unittests/BinaryFormat/DwarfTest.cpp
@@ -140,8 +140,8 @@ TEST(DwarfTest, getVirtuality) {
 }
 
 TEST(DwarfTest, FixedFormSizes) {
-  Optional<uint8_t> RefSize;
-  Optional<uint8_t> AddrSize;
+  std::optional<uint8_t> RefSize;
+  std::optional<uint8_t> AddrSize;
 
   // Test 32 bit DWARF version 2 with 4 byte addresses.
   FormParams Params_2_4_32 = {2, 4, DWARF32};
diff --git a/llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp b/llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp
index 40eecfb36e7d..155b799b22f9 100644
--- a/llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp
+++ b/llvm/unittests/DebugInfo/DWARF/DWARFDebugFrameTest.cpp
@@ -422,7 +422,7 @@ TEST(DWARFDebugFrame, RegisterLocations) {
   expectDumpResult(Locs, "reg12=[CFA+4], reg13=[CFA+8], reg14=same");
 
   // Verify RegisterLocations::getRegisterLocation() works as expected.
-  Optional<dwarf::UnwindLocation> OptionalLoc;
+  std::optional<dwarf::UnwindLocation> OptionalLoc;
   OptionalLoc = Locs.getRegisterLocation(0);
   EXPECT_FALSE(OptionalLoc.has_value());
 
diff --git a/llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp b/llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
index 3f113d65c9bf..4473c5af3db3 100644
--- a/llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
+++ b/llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
@@ -245,9 +245,9 @@ void TestAllForms() {
   //----------------------------------------------------------------------
   // Test block forms
   //----------------------------------------------------------------------
-  Optional<DWARFFormValue> FormValue;
+  std::optional<DWARFFormValue> FormValue;
   ArrayRef<uint8_t> ExtractedBlockData;
-  Optional<ArrayRef<uint8_t>> BlockDataOpt;
+  std::optional<ArrayRef<uint8_t>> BlockDataOpt;
 
   FormValue = DieDG.find(Attr_DW_FORM_block);
   EXPECT_TRUE((bool)FormValue);
@@ -937,7 +937,7 @@ template <uint16_t Version, class AddrType> void TestAddresses() {
   EXPECT_TRUE(DieDG.isValid());
 
   uint64_t LowPC, HighPC, SectionIndex;
-  Optional<uint64_t> OptU64;
+  std::optional<uint64_t> OptU64;
   // Verify the that our subprogram with no PC value fails appropriately when
   // asked for any PC values.
   auto SubprogramDieNoPC = DieDG.getFirstChild();
@@ -1118,14 +1118,14 @@ TEST(DWARFDebugInfo, TestStringOffsets) {
   ASSERT_TRUE((bool)Extracted1);
   EXPECT_STREQ(String1, *Extracted1);
 
-  Optional<DWARFFormValue> Form2 = DieDG.find(Attr2);
+  std::optional<DWARFFormValue> Form2 = DieDG.find(Attr2);
   ASSERT_TRUE((bool)Form2);
   EXPECT_EQ(0u, Form2->getRawUValue());
   auto Extracted2 = toString(Form2);
   ASSERT_TRUE((bool)Extracted2);
   EXPECT_STREQ(String2, *Extracted2);
 
-  Optional<DWARFFormValue> Form3 = DieDG.find(Attr3);
+  std::optional<DWARFFormValue> Form3 = DieDG.find(Attr3);
   ASSERT_TRUE((bool)Form3);
   EXPECT_EQ(1u, Form3->getRawUValue());
   auto Extracted3 = toString(Form3);
@@ -1632,13 +1632,13 @@ TEST(DWARFDebugInfo, TestFindRecurse) {
 
 TEST(DWARFDebugInfo, TestDwarfToFunctions) {
   // Test all of the dwarf::toXXX functions that take a
-  // Optional<DWARFFormValue> and extract the values from it.
+  // std::optional<DWARFFormValue> and extract the values from it.
   uint64_t InvalidU64 = 0xBADBADBADBADBADB;
   int64_t InvalidS64 = 0xBADBADBADBADBADB;
 
   // First test that we don't get valid values back when using an optional with
   // no value.
-  Optional<DWARFFormValue> FormValOpt1 = DWARFFormValue();
+  std::optional<DWARFFormValue> FormValOpt1 = DWARFFormValue();
   EXPECT_FALSE(toString(FormValOpt1).has_value());
   EXPECT_FALSE(toUnsigned(FormValOpt1).has_value());
   EXPECT_FALSE(toReference(FormValOpt1).has_value());
@@ -1655,7 +1655,7 @@ TEST(DWARFDebugInfo, TestDwarfToFunctions) {
 
   // Test successful and unsuccessful address decoding.
   uint64_t Address = 0x100000000ULL;
-  Optional<DWARFFormValue> FormValOpt2 =
+  std::optional<DWARFFormValue> FormValOpt2 =
       DWARFFormValue::createFromUValue(DW_FORM_addr, Address);
 
   EXPECT_FALSE(toString(FormValOpt2).has_value());
@@ -1674,7 +1674,7 @@ TEST(DWARFDebugInfo, TestDwarfToFunctions) {
 
   // Test successful and unsuccessful unsigned constant decoding.
   uint64_t UData8 = 0x1020304050607080ULL;
-  Optional<DWARFFormValue> FormValOpt3 =
+  std::optional<DWARFFormValue> FormValOpt3 =
       DWARFFormValue::createFromUValue(DW_FORM_udata, UData8);
 
   EXPECT_FALSE(toString(FormValOpt3).has_value());
@@ -1693,7 +1693,7 @@ TEST(DWARFDebugInfo, TestDwarfToFunctions) {
 
   // Test successful and unsuccessful reference decoding.
   uint32_t RefData = 0x11223344U;
-  Optional<DWARFFormValue> FormValOpt4 =
+  std::optional<DWARFFormValue> FormValOpt4 =
       DWARFFormValue::createFromUValue(DW_FORM_ref_addr, RefData);
 
   EXPECT_FALSE(toString(FormValOpt4).has_value());
@@ -1712,7 +1712,7 @@ TEST(DWARFDebugInfo, TestDwarfToFunctions) {
 
   // Test successful and unsuccessful signed constant decoding.
   int64_t SData8 = 0x1020304050607080ULL;
-  Optional<DWARFFormValue> FormValOpt5 =
+  std::optional<DWARFFormValue> FormValOpt5 =
       DWARFFormValue::createFromSValue(DW_FORM_udata, SData8);
 
   EXPECT_FALSE(toString(FormValOpt5).has_value());
@@ -1732,7 +1732,7 @@ TEST(DWARFDebugInfo, TestDwarfToFunctions) {
   // Test successful and unsuccessful block decoding.
   uint8_t Data[] = { 2, 3, 4 };
   ArrayRef<uint8_t> Array(Data);
-  Optional<DWARFFormValue> FormValOpt6 =
+  std::optional<DWARFFormValue> FormValOpt6 =
       DWARFFormValue::createFromBlockValue(DW_FORM_block1, Array);
 
   EXPECT_FALSE(toString(FormValOpt6).has_value());
@@ -1873,7 +1873,7 @@ TEST(DWARFDebugInfo, TestImplicitConstAbbrevs) {
     auto A = it->getAttrByIndex(0);
     EXPECT_EQ(A, Attr);
 
-    Optional<uint32_t> AttrIndex = it->findAttributeIndex(A);
+    std::optional<uint32_t> AttrIndex = it->findAttributeIndex(A);
     EXPECT_TRUE((bool)AttrIndex);
     EXPECT_EQ(*AttrIndex, 0u);
     uint64_t OffsetVal =
diff --git a/llvm/unittests/DebugInfo/DWARF/DWARFListTableTest.cpp b/llvm/unittests/DebugInfo/DWARF/DWARFListTableTest.cpp
index 8bb4d0fe59ba..1aedd74f3943 100644
--- a/llvm/unittests/DebugInfo/DWARF/DWARFListTableTest.cpp
+++ b/llvm/unittests/DebugInfo/DWARF/DWARFListTableTest.cpp
@@ -91,10 +91,10 @@ TEST(DWARFListTableHeader, OffsetEntryCount) {
                               /*ListTypeString=*/"range");
   uint64_t Offset = 0;
   EXPECT_FALSE(!!Header.extract(Extractor, &Offset));
-  Optional<uint64_t> Offset0 = Header.getOffsetEntry(Extractor, 0);
+  std::optional<uint64_t> Offset0 = Header.getOffsetEntry(Extractor, 0);
   EXPECT_TRUE(!!Offset0);
   EXPECT_EQ(Offset0, uint64_t(4));
-  Optional<uint64_t> Offset1 = Header.getOffsetEntry(Extractor, 1);
+  std::optional<uint64_t> Offset1 = Header.getOffsetEntry(Extractor, 1);
   EXPECT_FALSE(!!Offset1);
   EXPECT_EQ(Header.length(), sizeof(SecData) - 1);
 }