diff --git a/llvm/include/llvm/ADT/STLExtras.h b/llvm/include/llvm/ADT/STLExtras.h
--- a/llvm/include/llvm/ADT/STLExtras.h
+++ b/llvm/include/llvm/ADT/STLExtras.h
@@ -79,13 +79,6 @@
       typename std::add_const<T>::type>::type;
 };
 
-/// Utilities for detecting if a given trait holds for some set of arguments
-/// 'Args'. For example, the given trait could be used to detect if a given type
-/// has a copy assignment operator:
-///   template<class T>
-///   using has_copy_assign_t = decltype(std::declval<T&>()
-///                                                 = std::declval<const T&>());
-///   bool fooHasCopyAssign = is_detected<has_copy_assign_t, FooClass>::value;
 namespace detail {
 template <typename...> using void_t = void;
 template <class, template <class...> class Op, class... Args> struct detector {
@@ -97,16 +90,23 @@
 };
 } // end namespace detail
 
+/// Detects if a given trait holds for some set of arguments 'Args'.
+/// For example, the given trait could be used to detect if a given type
+/// has a copy assignment operator:
+///   template<class T>
+///   using has_copy_assign_t = decltype(std::declval<T&>()
+///                                                 = std::declval<const T&>());
+///   bool fooHasCopyAssign = is_detected<has_copy_assign_t, FooClass>::value;
 template <template <class...> class Op, class... Args>
 using is_detected = typename detail::detector<void, Op, Args...>::value_t;
 
-/// Check if a Callable type can be invoked with the given set of arg types.
 namespace detail {
 template <typename Callable, typename... Args>
 using is_invocable =
     decltype(std::declval<Callable &>()(std::declval<Args>()...));
 } // namespace detail
 
+/// Check if a Callable type can be invoked with the given set of arg types.
 template <typename Callable, typename... Args>
 using is_invocable = is_detected<detail::is_invocable, Callable, Args...>;
 
diff --git a/llvm/include/llvm/Analysis/ValueLattice.h b/llvm/include/llvm/Analysis/ValueLattice.h
--- a/llvm/include/llvm/Analysis/ValueLattice.h
+++ b/llvm/include/llvm/Analysis/ValueLattice.h
@@ -17,13 +17,13 @@
 //                               ValueLatticeElement
 //===----------------------------------------------------------------------===//
 
+namespace llvm {
+
 /// This class represents lattice values for constants.
 ///
 /// FIXME: This is basically just for bringup, this can be made a lot more rich
 /// in the future.
 ///
-
-namespace llvm {
 class ValueLatticeElement {
   enum ValueLatticeElementTy {
     /// This Value has no known value yet.  As a result, this implies the
diff --git a/llvm/include/llvm/BinaryFormat/MsgPackDocument.h b/llvm/include/llvm/BinaryFormat/MsgPackDocument.h
--- a/llvm/include/llvm/BinaryFormat/MsgPackDocument.h
+++ b/llvm/include/llvm/BinaryFormat/MsgPackDocument.h
@@ -5,7 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-///
+/// \file
 /// This file declares a class that exposes a simple in-memory representation
 /// of a document of MsgPack objects, that can be read from MsgPack, written to
 /// MsgPack, and inspected and modified in memory. This is intended to be a
diff --git a/llvm/include/llvm/CodeGen/AccelTable.h b/llvm/include/llvm/CodeGen/AccelTable.h
--- a/llvm/include/llvm/CodeGen/AccelTable.h
+++ b/llvm/include/llvm/CodeGen/AccelTable.h
@@ -5,9 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
-// This file contains support for writing accelerator tables.
-//
+/// \file
+/// This file contains support for writing accelerator tables.
+///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_ACCELTABLE_H
@@ -30,6 +30,7 @@
 #include <cstdint>
 #include <vector>
 
+/// \file
 /// The DWARF and Apple accelerator tables are an indirect hash table optimized
 /// for null lookup rather than access to known data. The Apple accelerator
 /// tables are a precursor of the newer DWARF v5 accelerator tables. Both
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/CSEInfo.h b/llvm/include/llvm/CodeGen/GlobalISel/CSEInfo.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/CSEInfo.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/CSEInfo.h
@@ -5,9 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Provides analysis for continuously CSEing during GISel passes.
-//
+///
 //===----------------------------------------------------------------------===//
 #ifndef LLVM_CODEGEN_GLOBALISEL_CSEINFO_H
 #define LLVM_CODEGEN_GLOBALISEL_CSEINFO_H
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/Combiner.h b/llvm/include/llvm/CodeGen/GlobalISel/Combiner.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/Combiner.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/Combiner.h
@@ -5,10 +5,10 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// This contains common code to drive combines. Combiner Passes will need to
 /// setup a CombinerInfo and call combineMachineFunction.
-//
+///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_GLOBALISEL_COMBINER_H
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/CombinerHelper.h b/llvm/include/llvm/CodeGen/GlobalISel/CombinerHelper.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/CombinerHelper.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/CombinerHelper.h
@@ -5,13 +5,13 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===--------------------------------------------------------------------===//
-//
+/// \file
 /// This contains common combine transformations that may be used in a combine
 /// pass,or by the target elsewhere.
 /// Targets can pick individual opcode transformations from the helper or use
 /// tryCombine which invokes all transformations. All of the transformations
 /// return true if the MachineInstruction changed and false otherwise.
-//
+///
 //===--------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_GLOBALISEL_COMBINERHELPER_H
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/CombinerInfo.h b/llvm/include/llvm/CodeGen/GlobalISel/CombinerInfo.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/CombinerInfo.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/CombinerInfo.h
@@ -5,7 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Interface for Targets to specify which operations are combined how and when.
 ///
 //===----------------------------------------------------------------------===//
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h b/llvm/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h
@@ -5,11 +5,12 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// This contains common code to allow clients to notify changes to machine
 /// instr.
-//
+///
 //===----------------------------------------------------------------------===//
+
 #ifndef LLVM_CODEGEN_GLOBALISEL_GISELCHANGEOBSERVER_H
 #define LLVM_CODEGEN_GLOBALISEL_GISELCHANGEOBSERVER_H
 
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h b/llvm/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h
@@ -5,11 +5,12 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Provides analysis for querying information about KnownBits during GISel
 /// passes.
-//
+///
 //===----------------------------------------------------------------------===//
+
 #ifndef LLVM_CODEGEN_GLOBALISEL_GISELKNOWNBITS_H
 #define LLVM_CODEGEN_GLOBALISEL_GISELKNOWNBITS_H
 
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h b/llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
@@ -5,10 +5,10 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Interface for Targets to specify which operations they can successfully
 /// select and how the others should be expanded most efficiently.
-//
+///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_GLOBALISEL_LEGALIZERINFO_H
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/LostDebugLocObserver.h b/llvm/include/llvm/CodeGen/GlobalISel/LostDebugLocObserver.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/LostDebugLocObserver.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/LostDebugLocObserver.h
@@ -5,9 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Tracks DebugLocs between checkpoints and verifies that they are transferred.
-//
+///
 //===----------------------------------------------------------------------===//
 #ifndef LLVM_CODEGEN_GLOBALISEL_LOSTDEBUGLOCOBSERVER_H
 #define LLVM_CODEGEN_GLOBALISEL_LOSTDEBUGLOCOBSERVER_H
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/MIPatternMatch.h b/llvm/include/llvm/CodeGen/GlobalISel/MIPatternMatch.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/MIPatternMatch.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/MIPatternMatch.h
@@ -5,10 +5,11 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Contains matchers for matching SSA Machine Instructions.
-//
+///
 //===----------------------------------------------------------------------===//
+
 #ifndef LLVM_CODEGEN_GLOBALISEL_MIPATTERNMATCH_H
 #define LLVM_CODEGEN_GLOBALISEL_MIPATTERNMATCH_H
 
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/RegBankSelect.h b/llvm/include/llvm/CodeGen/GlobalISel/RegBankSelect.h
--- a/llvm/include/llvm/CodeGen/GlobalISel/RegBankSelect.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/RegBankSelect.h
@@ -6,9 +6,10 @@
 //
 //===----------------------------------------------------------------------===//
 //
-/// \file This file describes the interface of the MachineFunctionPass
+/// \file
+/// This file describes the interface of the MachineFunctionPass
 /// responsible for assigning the generic virtual registers to register bank.
-
+///
 /// By default, the reg bank selector relies on local decisions to
 /// assign the register bank. In other words, it looks at one instruction
 /// at a time to decide where the operand of that instruction should live.
diff --git a/llvm/include/llvm/CodeGen/LowLevelType.h b/llvm/include/llvm/CodeGen/LowLevelType.h
--- a/llvm/include/llvm/CodeGen/LowLevelType.h
+++ b/llvm/include/llvm/CodeGen/LowLevelType.h
@@ -5,12 +5,12 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Implement a low-level type suitable for MachineInstr level instruction
 /// selection.
 ///
 /// This provides the CodeGen aspects of LowLevelType, such as Type conversion.
-//
+///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_LOWLEVELTYPE_H
diff --git a/llvm/include/llvm/CodeGen/Passes.h b/llvm/include/llvm/CodeGen/Passes.h
--- a/llvm/include/llvm/CodeGen/Passes.h
+++ b/llvm/include/llvm/CodeGen/Passes.h
@@ -32,7 +32,7 @@
 
 } // End llvm namespace
 
-/// List of target independent CodeGen pass IDs.
+// List of target independent CodeGen pass IDs.
 namespace llvm {
   FunctionPass *createAtomicExpandPass();
 
@@ -86,7 +86,7 @@
   /// MachineDominators - This pass is a machine dominators analysis pass.
   extern char &MachineDominatorsID;
 
-/// MachineDominanaceFrontier - This pass is a machine dominators analysis pass.
+  /// MachineDominanaceFrontier - This pass is a machine dominators analysis.
   extern char &MachineDominanceFrontierID;
 
   /// MachineRegionInfo - This pass computes SESE regions for machine functions.
diff --git a/llvm/include/llvm/CodeGen/TargetPassConfig.h b/llvm/include/llvm/CodeGen/TargetPassConfig.h
--- a/llvm/include/llvm/CodeGen/TargetPassConfig.h
+++ b/llvm/include/llvm/CodeGen/TargetPassConfig.h
@@ -5,9 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Target-Independent Code Generator Pass Configuration Options pass.
-//
+///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_TARGETPASSCONFIG_H
diff --git a/llvm/include/llvm/ExecutionEngine/Orc/SpeculateAnalyses.h b/llvm/include/llvm/ExecutionEngine/Orc/SpeculateAnalyses.h
--- a/llvm/include/llvm/ExecutionEngine/Orc/SpeculateAnalyses.h
+++ b/llvm/include/llvm/ExecutionEngine/Orc/SpeculateAnalyses.h
@@ -5,7 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-// \file
+/// \file
 /// Contains the Analyses and Result Interpretation to select likely functions
 /// to Speculatively compile before they are called. [Purely Experimentation]
 //===----------------------------------------------------------------------===//
diff --git a/llvm/include/llvm/IR/GlobalIFunc.h b/llvm/include/llvm/IR/GlobalIFunc.h
--- a/llvm/include/llvm/IR/GlobalIFunc.h
+++ b/llvm/include/llvm/IR/GlobalIFunc.h
@@ -6,7 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 ///
-/// \brief
+/// \file
 /// This file contains the declaration of the GlobalIFunc class, which
 /// represents a single indirect function in the IR. Indirect function uses
 /// ELF symbol type extension to mark that the address of a declaration should
diff --git a/llvm/include/llvm/IR/PassManagerImpl.h b/llvm/include/llvm/IR/PassManagerImpl.h
--- a/llvm/include/llvm/IR/PassManagerImpl.h
+++ b/llvm/include/llvm/IR/PassManagerImpl.h
@@ -5,7 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-///
+/// \file
 /// Provides implementations for PassManager and AnalysisManager template
 /// methods. These classes should be explicitly instantiated for any IR unit,
 /// and files doing the explicit instantiation should include this header.
diff --git a/llvm/include/llvm/IR/PassManagerInternal.h b/llvm/include/llvm/IR/PassManagerInternal.h
--- a/llvm/include/llvm/IR/PassManagerInternal.h
+++ b/llvm/include/llvm/IR/PassManagerInternal.h
@@ -28,7 +28,7 @@
 template <typename IRUnitT, typename... ExtraArgTs> class AnalysisManager;
 class PreservedAnalyses;
 
-/// Implementation details of the pass manager interfaces.
+// Implementation details of the pass manager interfaces.
 namespace detail {
 
 /// Template for the abstract base class used to dispatch
diff --git a/llvm/include/llvm/InterfaceStub/ELFObjHandler.h b/llvm/include/llvm/InterfaceStub/ELFObjHandler.h
--- a/llvm/include/llvm/InterfaceStub/ELFObjHandler.h
+++ b/llvm/include/llvm/InterfaceStub/ELFObjHandler.h
@@ -5,7 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===-----------------------------------------------------------------------===/
-///
+/// \file
 /// This supports reading and writing of elf dynamic shared objects.
 ///
 //===-----------------------------------------------------------------------===/
diff --git a/llvm/include/llvm/Support/BinaryStreamArray.h b/llvm/include/llvm/Support/BinaryStreamArray.h
--- a/llvm/include/llvm/Support/BinaryStreamArray.h
+++ b/llvm/include/llvm/Support/BinaryStreamArray.h
@@ -5,6 +5,19 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
+///
+/// \file
+/// Lightweight arrays that are backed by an arbitrary BinaryStream.  This file
+/// provides two different array implementations.
+///
+///     VarStreamArray - Arrays of variable length records.  The user specifies
+///       an Extractor type that can extract a record from a given offset and
+///       return the number of bytes consumed by the record.
+///
+///     FixedStreamArray - Arrays of fixed length records.  This is similar in
+///       spirit to ArrayRef<T>, but since it is backed by a BinaryStream, the
+///       elements of the array need not be laid out in contiguous memory.
+///
 
 #ifndef LLVM_SUPPORT_BINARYSTREAMARRAY_H
 #define LLVM_SUPPORT_BINARYSTREAMARRAY_H
@@ -17,16 +30,6 @@
 #include <cassert>
 #include <cstdint>
 
-/// Lightweight arrays that are backed by an arbitrary BinaryStream.  This file
-/// provides two different array implementations.
-///
-///     VarStreamArray - Arrays of variable length records.  The user specifies
-///       an Extractor type that can extract a record from a given offset and
-///       return the number of bytes consumed by the record.
-///
-///     FixedStreamArray - Arrays of fixed length records.  This is similar in
-///       spirit to ArrayRef<T>, but since it is backed by a BinaryStream, the
-///       elements of the array need not be laid out in contiguous memory.
 namespace llvm {
 
 /// VarStreamArrayExtractor is intended to be specialized to provide customized
diff --git a/llvm/include/llvm/Support/Chrono.h b/llvm/include/llvm/Support/Chrono.h
--- a/llvm/include/llvm/Support/Chrono.h
+++ b/llvm/include/llvm/Support/Chrono.h
@@ -72,9 +72,21 @@
                      StringRef Style);
 };
 
+namespace detail {
+template <typename Period> struct unit { static const char value[]; };
+template <typename Period> const char unit<Period>::value[] = "";
+
+template <> struct unit<std::ratio<3600>> { static const char value[]; };
+template <> struct unit<std::ratio<60>> { static const char value[]; };
+template <> struct unit<std::ratio<1>> { static const char value[]; };
+template <> struct unit<std::milli> { static const char value[]; };
+template <> struct unit<std::micro> { static const char value[]; };
+template <> struct unit<std::nano> { static const char value[]; };
+} // namespace detail
+
 /// Implementation of format_provider<T> for duration types.
 ///
-/// The options string of a duration  type has the grammar:
+/// The options string of a duration type has the grammar:
 ///
 ///   duration_options  ::= [unit][show_unit [number_options]]
 ///   unit              ::= `h`|`m`|`s`|`ms|`us`|`ns`
@@ -96,18 +108,6 @@
 ///  it is still possible to format it, provided you explicitly request a
 ///  display unit or you request that the unit is not displayed.
 
-namespace detail {
-template <typename Period> struct unit { static const char value[]; };
-template <typename Period> const char unit<Period>::value[] = "";
-
-template <> struct unit<std::ratio<3600>> { static const char value[]; };
-template <> struct unit<std::ratio<60>> { static const char value[]; };
-template <> struct unit<std::ratio<1>> { static const char value[]; };
-template <> struct unit<std::milli> { static const char value[]; };
-template <> struct unit<std::micro> { static const char value[]; };
-template <> struct unit<std::nano> { static const char value[]; };
-} // namespace detail
-
 template <typename Rep, typename Period>
 struct format_provider<std::chrono::duration<Rep, Period>> {
 private:
diff --git a/llvm/include/llvm/Support/LowLevelTypeImpl.h b/llvm/include/llvm/Support/LowLevelTypeImpl.h
--- a/llvm/include/llvm/Support/LowLevelTypeImpl.h
+++ b/llvm/include/llvm/Support/LowLevelTypeImpl.h
@@ -5,7 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// Implement a low-level type suitable for MachineInstr level instruction
 /// selection.
 ///
@@ -20,7 +20,7 @@
 /// Other information required for correct selection is expected to be carried
 /// by the opcode, or non-type flags. For example the distinction between G_ADD
 /// and G_FADD for int/float or fast-math flags.
-//
+///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_SUPPORT_LOWLEVELTYPEIMPL_H
diff --git a/llvm/include/llvm/Support/OptimizedStructLayout.h b/llvm/include/llvm/Support/OptimizedStructLayout.h
--- a/llvm/include/llvm/Support/OptimizedStructLayout.h
+++ b/llvm/include/llvm/Support/OptimizedStructLayout.h
@@ -6,6 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 ///
+/// \file
 /// This file provides an interface for laying out a sequence of fields
 /// as a struct in a way that attempts to minimizes the total space
 /// requirements of the struct while still satisfying the layout
@@ -22,7 +23,7 @@
 ///
 /// - First, it does not guarantee that the result is minimal in size.
 ///   There is no known efficient algoorithm to achieve minimality for
-///   unrestricted inputs.  Nonetheless, this algorithm 
+///   unrestricted inputs.  Nonetheless, this algorithm
 ///
 /// - Second, there are other ways that a struct layout could be optimized
 ///   besides space usage, such as locality.  This layout may have a mixed
diff --git a/llvm/lib/CodeGen/EdgeBundles.cpp b/llvm/lib/CodeGen/EdgeBundles.cpp
--- a/llvm/lib/CodeGen/EdgeBundles.cpp
+++ b/llvm/lib/CodeGen/EdgeBundles.cpp
@@ -68,9 +68,9 @@
   return false;
 }
 
-/// Specialize WriteGraph, the standard implementation won't work.
 namespace llvm {
 
+/// Specialize WriteGraph, the standard implementation won't work.
 template<>
 raw_ostream &WriteGraph<>(raw_ostream &O, const EdgeBundles &G,
                           bool ShortNames,
diff --git a/llvm/lib/CodeGen/LiveRangeUtils.h b/llvm/lib/CodeGen/LiveRangeUtils.h
--- a/llvm/lib/CodeGen/LiveRangeUtils.h
+++ b/llvm/lib/CodeGen/LiveRangeUtils.h
@@ -5,9 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+/// \file
 /// This file contains helper functions to modify live ranges.
-//
+///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_LIB_CODEGEN_LIVERANGEUTILS_H
diff --git a/llvm/lib/CodeGen/MachineSSAUpdater.cpp b/llvm/lib/CodeGen/MachineSSAUpdater.cpp
--- a/llvm/lib/CodeGen/MachineSSAUpdater.cpp
+++ b/llvm/lib/CodeGen/MachineSSAUpdater.cpp
@@ -234,10 +234,10 @@
   U.setReg(NewVR);
 }
 
-/// SSAUpdaterTraits<MachineSSAUpdater> - Traits for the SSAUpdaterImpl
-/// template, specialized for MachineSSAUpdater.
 namespace llvm {
 
+/// SSAUpdaterTraits<MachineSSAUpdater> - Traits for the SSAUpdaterImpl
+/// template, specialized for MachineSSAUpdater.
 template<>
 class SSAUpdaterTraits<MachineSSAUpdater> {
 public:
diff --git a/llvm/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp b/llvm/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
--- a/llvm/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
@@ -54,10 +54,9 @@
 #define GET_DAGISEL_BODY HexagonDAGToDAGISel
 #include "HexagonGenDAGISel.inc"
 
+namespace llvm {
 /// createHexagonISelDag - This pass converts a legalized DAG into a
 /// Hexagon-specific DAG, ready for instruction scheduling.
-///
-namespace llvm {
 FunctionPass *createHexagonISelDag(HexagonTargetMachine &TM,
                                    CodeGenOpt::Level OptLevel) {
   return new HexagonDAGToDAGISel(TM, OptLevel);
diff --git a/llvm/lib/Target/X86/ImmutableGraph.h b/llvm/lib/Target/X86/ImmutableGraph.h
--- a/llvm/lib/Target/X86/ImmutableGraph.h
+++ b/llvm/lib/Target/X86/ImmutableGraph.h
@@ -5,7 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-///
+/// \file
 /// Description: ImmutableGraph is a fast DAG implementation that cannot be
 /// modified, except by creating a new ImmutableGraph. ImmutableGraph is
 /// implemented as two arrays: one containing nodes, and one containing edges.
diff --git a/llvm/lib/Target/X86/X86OptimizeLEAs.cpp b/llvm/lib/Target/X86/X86OptimizeLEAs.cpp
--- a/llvm/lib/Target/X86/X86OptimizeLEAs.cpp
+++ b/llvm/lib/Target/X86/X86OptimizeLEAs.cpp
@@ -112,9 +112,9 @@
 
 } // end anonymous namespace
 
-/// Provide DenseMapInfo for MemOpKey.
 namespace llvm {
 
+/// Provide DenseMapInfo for MemOpKey.
 template <> struct DenseMapInfo<MemOpKey> {
   using PtrInfo = DenseMapInfo<const MachineOperand *>;