From 0bad578cf3572506196e6f944aebc05d295c4e14 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nicol=C3=A1s=20Alvarez?= <nicolas.alvarez@gmail.com>
Date: Wed, 7 Apr 2021 00:15:04 +0200
Subject: [PATCH] [docs] Fix doxygen comments wrongly attached to the llvm
 namespace

Looking at the Doxygen-generated documentation for the llvm namespace
currently shows all sorts of random comments from different parts of the
codebase. These are mostly caused by:

- File doc comments that aren't marked with \file, so they're attached to
  the next declaration, which is usually "namespace llvm {".
- Class doc comments placed before the namespace rather than before the
  class.
- Code comments before the namespace that (in my opinion) shouldn't be
  extracted by doxygen at all.

This commit fixes these comments. The generated doxygen documentation now
has proper docs for several classes and files, and the docs for the llvm
and llvm::detail namespaces are now empty.

Reviewed By: thakis, mizvekov

Differential Revision: https://reviews.llvm.org/D96736
---
 include/llvm/ADT/STLExtras.h                  | 16 ++++++------
 include/llvm/Analysis/ValueLattice.h          |  4 +--
 include/llvm/BinaryFormat/MsgPackDocument.h   |  2 +-
 include/llvm/CodeGen/AccelTable.h             |  7 ++---
 include/llvm/CodeGen/GlobalISel/CSEInfo.h     |  4 +--
 include/llvm/CodeGen/GlobalISel/Combiner.h    |  4 +--
 .../llvm/CodeGen/GlobalISel/CombinerHelper.h  |  4 +--
 .../llvm/CodeGen/GlobalISel/CombinerInfo.h    |  2 +-
 .../CodeGen/GlobalISel/GISelChangeObserver.h  |  5 ++--
 .../llvm/CodeGen/GlobalISel/GISelKnownBits.h  |  5 ++--
 .../llvm/CodeGen/GlobalISel/LegalizerInfo.h   |  4 +--
 .../CodeGen/GlobalISel/LostDebugLocObserver.h |  4 +--
 .../llvm/CodeGen/GlobalISel/MIPatternMatch.h  |  5 ++--
 .../llvm/CodeGen/GlobalISel/RegBankSelect.h   |  5 ++--
 include/llvm/CodeGen/LowLevelType.h           |  4 +--
 include/llvm/CodeGen/Passes.h                 |  4 +--
 include/llvm/CodeGen/TargetPassConfig.h       |  4 +--
 .../ExecutionEngine/Orc/SpeculateAnalyses.h   |  2 +-
 include/llvm/IR/GlobalIFunc.h                 |  2 +-
 include/llvm/IR/PassManagerImpl.h             |  2 +-
 include/llvm/IR/PassManagerInternal.h         |  2 +-
 include/llvm/InterfaceStub/ELFObjHandler.h    |  2 +-
 include/llvm/Support/BinaryStreamArray.h      | 23 +++++++++-------
 include/llvm/Support/Chrono.h                 | 26 +++++++++----------
 include/llvm/Support/LowLevelTypeImpl.h       |  4 +--
 include/llvm/Support/OptimizedStructLayout.h  |  3 ++-
 lib/CodeGen/EdgeBundles.cpp                   |  2 +-
 lib/CodeGen/LiveRangeUtils.h                  |  4 +--
 lib/CodeGen/MachineSSAUpdater.cpp             |  4 +--
 lib/Target/Hexagon/HexagonISelDAGToDAG.cpp    |  3 +--
 lib/Target/X86/ImmutableGraph.h               |  2 +-
 lib/Target/X86/X86OptimizeLEAs.cpp            |  2 +-
 32 files changed, 87 insertions(+), 79 deletions(-)

diff --git a/include/llvm/ADT/STLExtras.h b/include/llvm/ADT/STLExtras.h
index dd09cf8cc9e..208156ceaaf 100644
--- a/include/llvm/ADT/STLExtras.h
+++ b/include/llvm/ADT/STLExtras.h
@@ -79,13 +79,6 @@ template <typename T> struct make_const_ref {
       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 @@ struct detector<void_t<Op<Args...>>, Op, Args...> {
 };
 } // 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/include/llvm/Analysis/ValueLattice.h b/include/llvm/Analysis/ValueLattice.h
index 108d08033ac..5ff9c4a6b08 100644
--- a/include/llvm/Analysis/ValueLattice.h
+++ b/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/include/llvm/BinaryFormat/MsgPackDocument.h b/include/llvm/BinaryFormat/MsgPackDocument.h
index 91778f6a99d..6d7aca89ee5 100644
--- a/include/llvm/BinaryFormat/MsgPackDocument.h
+++ b/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/include/llvm/CodeGen/AccelTable.h b/include/llvm/CodeGen/AccelTable.h
index 3915badfadd..1190d6061e4 100644
--- a/include/llvm/CodeGen/AccelTable.h
+++ b/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/include/llvm/CodeGen/GlobalISel/CSEInfo.h b/include/llvm/CodeGen/GlobalISel/CSEInfo.h
index f76dec57c84..dd213bf68e6 100644
--- a/include/llvm/CodeGen/GlobalISel/CSEInfo.h
+++ b/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/include/llvm/CodeGen/GlobalISel/Combiner.h b/include/llvm/CodeGen/GlobalISel/Combiner.h
index bad541b10d6..79568698084 100644
--- a/include/llvm/CodeGen/GlobalISel/Combiner.h
+++ b/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/include/llvm/CodeGen/GlobalISel/CombinerHelper.h b/include/llvm/CodeGen/GlobalISel/CombinerHelper.h
index 932952d311c..80cc68f8777 100644
--- a/include/llvm/CodeGen/GlobalISel/CombinerHelper.h
+++ b/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/include/llvm/CodeGen/GlobalISel/CombinerInfo.h b/include/llvm/CodeGen/GlobalISel/CombinerInfo.h
index df5ecbfde78..4a1a4ff2528 100644
--- a/include/llvm/CodeGen/GlobalISel/CombinerInfo.h
+++ b/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/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h b/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h
index dd7f04a33f4..79d71b2c898 100644
--- a/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h
+++ b/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/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h b/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h
index e2e35cdd2c2..035c5a08fee 100644
--- a/include/llvm/CodeGen/GlobalISel/GISelKnownBits.h
+++ b/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/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h b/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
index c0a89b6ae61..2d26e8306b7 100644
--- a/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
+++ b/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/include/llvm/CodeGen/GlobalISel/LostDebugLocObserver.h b/include/llvm/CodeGen/GlobalISel/LostDebugLocObserver.h
index b2816e48489..1667d0145b0 100644
--- a/include/llvm/CodeGen/GlobalISel/LostDebugLocObserver.h
+++ b/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/include/llvm/CodeGen/GlobalISel/MIPatternMatch.h b/include/llvm/CodeGen/GlobalISel/MIPatternMatch.h
index cf82ecdd071..ebcb9347a50 100644
--- a/include/llvm/CodeGen/GlobalISel/MIPatternMatch.h
+++ b/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/include/llvm/CodeGen/GlobalISel/RegBankSelect.h b/include/llvm/CodeGen/GlobalISel/RegBankSelect.h
index d9d076ba312..5c693d8de52 100644
--- a/include/llvm/CodeGen/GlobalISel/RegBankSelect.h
+++ b/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/include/llvm/CodeGen/LowLevelType.h b/include/llvm/CodeGen/LowLevelType.h
index 402fa2ce61e..40985e16b37 100644
--- a/include/llvm/CodeGen/LowLevelType.h
+++ b/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/include/llvm/CodeGen/Passes.h b/include/llvm/CodeGen/Passes.h
index bca0c763ee1..c01f5290d14 100644
--- a/include/llvm/CodeGen/Passes.h
+++ b/include/llvm/CodeGen/Passes.h
@@ -32,7 +32,7 @@ class raw_ostream;
 
 } // 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 @@ namespace llvm {
   /// 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/include/llvm/CodeGen/TargetPassConfig.h b/include/llvm/CodeGen/TargetPassConfig.h
index b4787710379..1511045e468 100644
--- a/include/llvm/CodeGen/TargetPassConfig.h
+++ b/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/include/llvm/ExecutionEngine/Orc/SpeculateAnalyses.h b/include/llvm/ExecutionEngine/Orc/SpeculateAnalyses.h
index cf57b63b644..67565728175 100644
--- a/include/llvm/ExecutionEngine/Orc/SpeculateAnalyses.h
+++ b/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/include/llvm/IR/GlobalIFunc.h b/include/llvm/IR/GlobalIFunc.h
index 0fdae917878..ddd29c8a4a1 100644
--- a/include/llvm/IR/GlobalIFunc.h
+++ b/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/include/llvm/IR/PassManagerImpl.h b/include/llvm/IR/PassManagerImpl.h
index 71a86d1efb1..79dc8cf4f15 100644
--- a/include/llvm/IR/PassManagerImpl.h
+++ b/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/include/llvm/IR/PassManagerInternal.h b/include/llvm/IR/PassManagerInternal.h
index 986ed0b5a7a..8f42e69f306 100644
--- a/include/llvm/IR/PassManagerInternal.h
+++ b/include/llvm/IR/PassManagerInternal.h
@@ -28,7 +28,7 @@ template <typename IRUnitT> class AllAnalysesOn;
 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/include/llvm/InterfaceStub/ELFObjHandler.h b/include/llvm/InterfaceStub/ELFObjHandler.h
index a947327a728..43cac176d10 100644
--- a/include/llvm/InterfaceStub/ELFObjHandler.h
+++ b/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/include/llvm/Support/BinaryStreamArray.h b/include/llvm/Support/BinaryStreamArray.h
index 3ba65c07cfe..148ab85169f 100644
--- a/include/llvm/Support/BinaryStreamArray.h
+++ b/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/include/llvm/Support/Chrono.h b/include/llvm/Support/Chrono.h
index 098512dce78..f478549a7e4 100644
--- a/include/llvm/Support/Chrono.h
+++ b/include/llvm/Support/Chrono.h
@@ -72,9 +72,21 @@ struct format_provider<sys::TimePoint<>> {
                      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 @@ struct format_provider<sys::TimePoint<>> {
 ///  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/include/llvm/Support/LowLevelTypeImpl.h b/include/llvm/Support/LowLevelTypeImpl.h
index c1d516f2fe5..28efaa06c95 100644
--- a/include/llvm/Support/LowLevelTypeImpl.h
+++ b/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/include/llvm/Support/OptimizedStructLayout.h b/include/llvm/Support/OptimizedStructLayout.h
index 773ddfeaf13..619990d132b 100644
--- a/include/llvm/Support/OptimizedStructLayout.h
+++ b/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/lib/CodeGen/EdgeBundles.cpp b/lib/CodeGen/EdgeBundles.cpp
index 67922e93a52..3dd354e8ab7 100644
--- a/lib/CodeGen/EdgeBundles.cpp
+++ b/lib/CodeGen/EdgeBundles.cpp
@@ -68,9 +68,9 @@ bool EdgeBundles::runOnMachineFunction(MachineFunction &mf) {
   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/lib/CodeGen/LiveRangeUtils.h b/lib/CodeGen/LiveRangeUtils.h
index 0e6bfeb0d4a..dace05f1ad9 100644
--- a/lib/CodeGen/LiveRangeUtils.h
+++ b/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/lib/CodeGen/MachineSSAUpdater.cpp b/lib/CodeGen/MachineSSAUpdater.cpp
index 71bf755a42a..930677e4fd7 100644
--- a/lib/CodeGen/MachineSSAUpdater.cpp
+++ b/lib/CodeGen/MachineSSAUpdater.cpp
@@ -234,10 +234,10 @@ void MachineSSAUpdater::RewriteUse(MachineOperand &U) {
   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/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp b/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
index bdd5c7dd151..fd404a15690 100644
--- a/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
+++ b/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
@@ -54,10 +54,9 @@ static cl::opt<bool> CheckSingleUse("hexagon-isel-su", cl::Hidden,
 #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/lib/Target/X86/ImmutableGraph.h b/lib/Target/X86/ImmutableGraph.h
index 56738e9cfa7..e60497cfdbb 100644
--- a/lib/Target/X86/ImmutableGraph.h
+++ b/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/lib/Target/X86/X86OptimizeLEAs.cpp b/lib/Target/X86/X86OptimizeLEAs.cpp
index 220fd0b7374..ab4d2bd0577 100644
--- a/lib/Target/X86/X86OptimizeLEAs.cpp
+++ b/lib/Target/X86/X86OptimizeLEAs.cpp
@@ -112,9 +112,9 @@ public:
 
 } // end anonymous namespace
 
-/// Provide DenseMapInfo for MemOpKey.
 namespace llvm {
 
+/// Provide DenseMapInfo for MemOpKey.
 template <> struct DenseMapInfo<MemOpKey> {
   using PtrInfo = DenseMapInfo<const MachineOperand *>;