vendor/llvm-project/llvmorg-15-init-16436-g18a6ab5b8d1f

141 files changed, 3406 insertions, 1042 deletions

diff --git a/clang/include/clang/APINotes/Types.h b/clang/include/clang/APINotes/Types.h
index d79586931995..0e5b43080e4b 100644
--- a/clang/include/clang/APINotes/Types.h
+++ b/clang/include/clang/APINotes/Types.h
@@ -76,7 +76,7 @@ public:
   }
 
   void setSwiftPrivate(llvm::Optional<bool> Private) {
-    SwiftPrivateSpecified = Private.hasValue();
+    SwiftPrivateSpecified = Private.has_value();
     SwiftPrivate = Private ? *Private : 0;
   }
 
diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index 7db6af9cb87d..85eba45e4de6 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -130,6 +130,7 @@ class TemplateDecl;
 class TemplateParameterList;
 class TemplateTemplateParmDecl;
 class TemplateTypeParmDecl;
+class TypeConstraint;
 class UnresolvedSetIterator;
 class UsingShadowDecl;
 class VarTemplateDecl;
@@ -260,7 +261,7 @@ class ASTContext : public RefCountedBase<ASTContext> {
   mutable llvm::FoldingSet<DeducedTemplateSpecializationType>
     DeducedTemplateSpecializationTypes;
   mutable llvm::FoldingSet<AtomicType> AtomicTypes;
-  llvm::FoldingSet<AttributedType> AttributedTypes;
+  mutable llvm::FoldingSet<AttributedType> AttributedTypes;
   mutable llvm::FoldingSet<PipeType> PipeTypes;
   mutable llvm::FoldingSet<BitIntType> BitIntTypes;
   mutable llvm::FoldingSet<DependentBitIntType> DependentBitIntTypes;
@@ -1306,11 +1307,11 @@ public:
   /// declaration of a function with an exception specification is permitted
   /// and preserved. Other type sugar (for instance, typedefs) is not.
   QualType getFunctionTypeWithExceptionSpec(
-      QualType Orig, const FunctionProtoType::ExceptionSpecInfo &ESI);
+      QualType Orig, const FunctionProtoType::ExceptionSpecInfo &ESI) const;
 
   /// Determine whether two function types are the same, ignoring
   /// exception specifications in cases where they're part of the type.
-  bool hasSameFunctionTypeIgnoringExceptionSpec(QualType T, QualType U);
+  bool hasSameFunctionTypeIgnoringExceptionSpec(QualType T, QualType U) const;
 
   /// Change the exception specification on a function once it is
   /// delay-parsed, instantiated, or computed.
@@ -1597,9 +1598,8 @@ public:
 
   QualType getInjectedClassNameType(CXXRecordDecl *Decl, QualType TST) const;
 
-  QualType getAttributedType(attr::Kind attrKind,
-                             QualType modifiedType,
-                             QualType equivalentType);
+  QualType getAttributedType(attr::Kind attrKind, QualType modifiedType,
+                             QualType equivalentType) const;
 
   QualType getBTFTagAttributedType(const BTFTypeTagAttr *BTFAttr,
                                    QualType Wrapped);
@@ -2654,25 +2654,33 @@ public:
   bool hasSameTemplateName(const TemplateName &X, const TemplateName &Y) const;
 
   /// Determine whether the two declarations refer to the same entity.
-  ///
-  /// FIXME: isSameEntity is not const due to its implementation calls
-  /// hasSameFunctionTypeIgnoringExceptionSpec which may alter this.
-  bool isSameEntity(const NamedDecl *X, const NamedDecl *Y);
+  bool isSameEntity(const NamedDecl *X, const NamedDecl *Y) const;
 
   /// Determine whether two template parameter lists are similar enough
   /// that they may be used in declarations of the same template.
-  ///
-  /// FIXME: isSameTemplateParameterList is not const since it calls
-  /// isSameTemplateParameter.
   bool isSameTemplateParameterList(const TemplateParameterList *X,
-                                   const TemplateParameterList *Y);
+                                   const TemplateParameterList *Y) const;
 
   /// Determine whether two template parameters are similar enough
   /// that they may be used in declarations of the same template.
+  bool isSameTemplateParameter(const NamedDecl *X, const NamedDecl *Y) const;
+
+  /// Determine whether two 'requires' expressions are similar enough that they
+  /// may be used in re-declarations.
   ///
-  /// FIXME: isSameTemplateParameterList is not const since it calls
-  /// isSameEntity.
-  bool isSameTemplateParameter(const NamedDecl *X, const NamedDecl *Y);
+  /// Use of 'requires' isn't mandatory, works with constraints expressed in
+  /// other ways too.
+  bool isSameConstraintExpr(const Expr *XCE, const Expr *YCE) const;
+
+  /// Determine whether two type contraint are similar enough that they could
+  /// used in declarations of the same template.
+  bool isSameTypeConstraint(const TypeConstraint *XTC,
+                            const TypeConstraint *YTC) const;
+
+  /// Determine whether two default template arguments are similar enough
+  /// that they may be used in declarations of the same template.
+  bool isSameDefaultTemplateArgument(const NamedDecl *X,
+                                     const NamedDecl *Y) const;
 
   /// Retrieve the "canonical" template argument.
   ///
diff --git a/clang/include/clang/AST/ASTImportError.h b/clang/include/clang/AST/ASTImportError.h
index 405790b6ded3..728314ca0936 100644
--- a/clang/include/clang/AST/ASTImportError.h
+++ b/clang/include/clang/AST/ASTImportError.h
@@ -19,7 +19,6 @@
 namespace clang {
 
 class ASTImportError : public llvm::ErrorInfo<ASTImportError> {
-
 public:
   /// \brief Kind of error when importing an AST component.
   enum ErrorKind {
diff --git a/clang/include/clang/AST/DeclTemplate.h b/clang/include/clang/AST/DeclTemplate.h
index 3e4ccda73111..725bb0bced9c 100644
--- a/clang/include/clang/AST/DeclTemplate.h
+++ b/clang/include/clang/AST/DeclTemplate.h
@@ -15,6 +15,7 @@
 #define LLVM_CLANG_AST_DECLTEMPLATE_H
 
 #include "clang/AST/ASTConcept.h"
+#include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclBase.h"
 #include "clang/AST/DeclCXX.h"
@@ -373,11 +374,19 @@ public:
 
   /// Set that the default argument was inherited from another parameter.
   void setInherited(const ASTContext &C, ParmDecl *InheritedFrom) {
-    assert(!isInherited() && "default argument already inherited");
     InheritedFrom = getParmOwningDefaultArg(InheritedFrom);
     if (!isSet())
       ValueOrInherited = InheritedFrom;
-    else
+    else if (auto *D = ValueOrInherited.template dyn_cast<ParmDecl *>()) {
+      assert(C.isSameDefaultTemplateArgument(D, InheritedFrom));
+      ValueOrInherited =
+          new (allocateDefaultArgStorageChain(C)) Chain{InheritedFrom, get()};
+    } else if (auto *Inherited =
+                   ValueOrInherited.template dyn_cast<Chain *>()) {
+      assert(C.isSameDefaultTemplateArgument(Inherited->PrevDeclWithDefaultArg,
+                                             InheritedFrom));
+      Inherited->PrevDeclWithDefaultArg = InheritedFrom;
+    } else
       ValueOrInherited = new (allocateDefaultArgStorageChain(C))
           Chain{InheritedFrom, ValueOrInherited.template get<ArgType>()};
   }
diff --git a/clang/include/clang/AST/PropertiesBase.td b/clang/include/clang/AST/PropertiesBase.td
index 559f29edcf0f..ec310a459927 100644
--- a/clang/include/clang/AST/PropertiesBase.td
+++ b/clang/include/clang/AST/PropertiesBase.td
@@ -520,15 +520,15 @@ let Class = PropertyTypeCase<APValue, "LValue"> in {
     if (hasBase) {
       if (isTypeInfo) {
         base = APValue::LValueBase::getTypeInfo(
-            TypeInfoLValue(typeInfo.getValue().getTypePtr()), type.getValue());
+            TypeInfoLValue(typeInfo.value().getTypePtr()), type.value());
         elemTy = base.getTypeInfoType();
       } else if (isExpr) {
-        base = APValue::LValueBase(cast<Expr>(stmt.getValue()),
-                                   callIndex.getValue(), version.getValue());
+        base = APValue::LValueBase(cast<Expr>(stmt.value()),
+                                   callIndex.value(), version.value());
         elemTy = base.get<const Expr *>()->getType();
       } else {
-        base = APValue::LValueBase(cast<ValueDecl>(decl.getValue()),
-                                   callIndex.getValue(), version.getValue());
+        base = APValue::LValueBase(cast<ValueDecl>(decl.value()),
+                                   callIndex.value(), version.value());
         elemTy = base.get<const ValueDecl *>()->getType();
       }
     }
diff --git a/clang/include/clang/Analysis/FlowSensitive/DataflowAnalysisContext.h b/clang/include/clang/Analysis/FlowSensitive/DataflowAnalysisContext.h
index c1100d8474aa..358ace0430f6 100644
--- a/clang/include/clang/Analysis/FlowSensitive/DataflowAnalysisContext.h
+++ b/clang/include/clang/Analysis/FlowSensitive/DataflowAnalysisContext.h
@@ -155,6 +155,7 @@ public:
 
   /// Returns a pointer value that represents a null pointer. Calls with
   /// `PointeeType` that are canonically equivalent will return the same result.
+  /// A null `PointeeType` can be used for the pointee of `std::nullptr_t`.
   PointerValue &getOrCreateNullPointerValue(QualType PointeeType);
 
   /// Returns a symbolic boolean value that models a boolean literal equal to
@@ -251,6 +252,17 @@ public:
   bool equivalentBoolValues(BoolValue &Val1, BoolValue &Val2);
 
 private:
+  struct NullableQualTypeDenseMapInfo : private llvm::DenseMapInfo<QualType> {
+    static QualType getEmptyKey() {
+      // Allow a NULL `QualType` by using a different value as the empty key.
+      return QualType::getFromOpaquePtr(reinterpret_cast<Type *>(1));
+    }
+
+    using DenseMapInfo::getHashValue;
+    using DenseMapInfo::getTombstoneKey;
+    using DenseMapInfo::isEqual;
+  };
+
   /// Adds all constraints of the flow condition identified by `Token` and all
   /// of its transitive dependencies to `Constraints`. `VisitedTokens` is used
   /// to track tokens of flow conditions that were already visited by recursive
@@ -259,17 +271,18 @@ private:
       AtomicBoolValue &Token, llvm::DenseSet<BoolValue *> &Constraints,
       llvm::DenseSet<AtomicBoolValue *> &VisitedTokens);
 
-  /// Returns the result of satisfiability checking on `Constraints`.
-  /// Possible return values are:
-  /// - `Satisfiable`: There exists a satisfying assignment for `Constraints`.
-  /// - `Unsatisfiable`: There is no satisfying assignment for `Constraints`.
-  /// - `TimedOut`: The solver gives up on finding a satisfying assignment.
+  /// Returns the outcome of satisfiability checking on `Constraints`.
+  /// Possible outcomes are:
+  /// - `Satisfiable`: A satisfying assignment exists and is returned.
+  /// - `Unsatisfiable`: A satisfying assignment does not exist.
+  /// - `TimedOut`: The search for a satisfying assignment was not completed.
   Solver::Result querySolver(llvm::DenseSet<BoolValue *> Constraints);
 
   /// Returns true if the solver is able to prove that there is no satisfying
   /// assignment for `Constraints`
   bool isUnsatisfiable(llvm::DenseSet<BoolValue *> Constraints) {
-    return querySolver(std::move(Constraints)) == Solver::Result::Unsatisfiable;
+    return querySolver(std::move(Constraints)).getStatus() ==
+           Solver::Result::Status::Unsatisfiable;
   }
 
   /// Returns a boolean value as a result of substituting `Val` and its sub
@@ -311,7 +324,8 @@ private:
   // required to initialize the `PointeeLoc` field in `PointerValue`. Consider
   // creating a type-independent `NullPointerValue` without a `PointeeLoc`
   // field.
-  llvm::DenseMap<QualType, PointerValue *> NullPointerVals;
+  llvm::DenseMap<QualType, PointerValue *, NullableQualTypeDenseMapInfo>
+      NullPointerVals;
 
   AtomicBoolValue &TrueVal;
   AtomicBoolValue &FalseVal;
diff --git a/clang/include/clang/Analysis/FlowSensitive/DebugSupport.h b/clang/include/clang/Analysis/FlowSensitive/DebugSupport.h
new file mode 100644
index 000000000000..ef903d807e12
--- /dev/null
+++ b/clang/include/clang/Analysis/FlowSensitive/DebugSupport.h
@@ -0,0 +1,63 @@
+//===-- DebugSupport.h ------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines functions which generate more readable forms of data
+//  structures used in the dataflow analyses, for debugging purposes.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_DEBUGSUPPORT_H_
+#define LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_DEBUGSUPPORT_H_
+
+#include <string>
+#include <vector>
+
+#include "clang/Analysis/FlowSensitive/Solver.h"
+#include "clang/Analysis/FlowSensitive/Value.h"
+#include "llvm/ADT/DenseMap.h"
+
+namespace clang {
+namespace dataflow {
+/// Returns a string representation for the boolean value `B`.
+///
+/// Atomic booleans appearing in the boolean value `B` are assigned to labels
+/// either specified in `AtomNames` or created by default rules as B0, B1, ...
+///
+/// Requirements:
+///
+///   Names assigned to atoms should not be repeated in `AtomNames`.
+std::string debugString(
+    const BoolValue &B,
+    llvm::DenseMap<const AtomicBoolValue *, std::string> AtomNames = {{}});
+
+/// Returns a string representation for `Constraints` - a collection of boolean
+/// formulas and the `Result` of satisfiability checking.
+///
+/// Atomic booleans appearing in `Constraints` and `Result` are assigned to
+/// labels either specified in `AtomNames` or created by default rules as B0,
+/// B1, ...
+///
+/// Requirements:
+///
+///   Names assigned to atoms should not be repeated in `AtomNames`.
+std::string debugString(
+    const std::vector<BoolValue *> &Constraints, const Solver::Result &Result,
+    llvm::DenseMap<const AtomicBoolValue *, std::string> AtomNames = {{}});
+inline std::string debugString(
+    const llvm::DenseSet<BoolValue *> &Constraints,
+    const Solver::Result &Result,
+    llvm::DenseMap<const AtomicBoolValue *, std::string> AtomNames = {{}}) {
+  std::vector<BoolValue *> ConstraintsVec(Constraints.begin(),
+                                          Constraints.end());
+  return debugString(ConstraintsVec, Result, std::move(AtomNames));
+}
+
+} // namespace dataflow
+} // namespace clang
+
+#endif // LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_DEBUGSUPPORT_H_
diff --git a/clang/include/clang/Analysis/FlowSensitive/Solver.h b/clang/include/clang/Analysis/FlowSensitive/Solver.h
index 6b685b9b3c9a..93568b119793 100644
--- a/clang/include/clang/Analysis/FlowSensitive/Solver.h
+++ b/clang/include/clang/Analysis/FlowSensitive/Solver.h
@@ -15,7 +15,9 @@
 #define LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_SOLVER_H
 
 #include "clang/Analysis/FlowSensitive/Value.h"
+#include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/Optional.h"
 
 namespace clang {
 namespace dataflow {
@@ -23,17 +25,58 @@ namespace dataflow {
 /// An interface for a SAT solver that can be used by dataflow analyses.
 class Solver {
 public:
-  enum class Result {
-    /// Indicates that there exists a satisfying assignment for a boolean
+  struct Result {
+    enum class Status {
+      /// Indicates that there exists a satisfying assignment for a boolean
+      /// formula.
+      Satisfiable,
+
+      /// Indicates that there is no satisfying assignment for a boolean
+      /// formula.
+      Unsatisfiable,
+
+      /// Indicates that the solver gave up trying to find a satisfying
+      /// assignment for a boolean formula.
+      TimedOut,
+    };
+
+    /// A boolean value is set to true or false in a truth assignment.
+    enum class Assignment : uint8_t { AssignedFalse = 0, AssignedTrue = 1 };
+
+    /// Constructs a result indicating that the queried boolean formula is
+    /// satisfiable. The result will hold a solution found by the solver.
+    static Result
+    Satisfiable(llvm::DenseMap<AtomicBoolValue *, Assignment> Solution) {
+      return Result(Status::Satisfiable, std::move(Solution));
+    }
+
+    /// Constructs a result indicating that the queried boolean formula is
+    /// unsatisfiable.
+    static Result Unsatisfiable() { return Result(Status::Unsatisfiable, {}); }
+
+    /// Constructs a result indicating that satisfiability checking on the
+    /// queried boolean formula was not completed.
+    static Result TimedOut() { return Result(Status::TimedOut, {}); }
+
+    /// Returns the status of satisfiability checking on the queried boolean
     /// formula.
-    Satisfiable,
+    Status getStatus() const { return SATCheckStatus; }
 
-    /// Indicates that there is no satisfying assignment for a boolean formula.
-    Unsatisfiable,
+    /// Returns a truth assignment to boolean values that satisfies the queried
+    /// boolean formula if available. Otherwise, an empty optional is returned.
+    llvm::Optional<llvm::DenseMap<AtomicBoolValue *, Assignment>>
+    getSolution() const {
+      return Solution;
+    }
 
-    /// Indicates that the solver gave up trying to find a satisfying assignment
-    /// for a boolean formula.
-    TimedOut,
+  private:
+    Result(
+        enum Status SATCheckStatus,
+        llvm::Optional<llvm::DenseMap<AtomicBoolValue *, Assignment>> Solution)
+        : SATCheckStatus(SATCheckStatus), Solution(std::move(Solution)) {}
+
+    Status SATCheckStatus;
+    llvm::Optional<llvm::DenseMap<AtomicBoolValue *, Assignment>> Solution;
   };
 
   virtual ~Solver() = default;
@@ -44,9 +87,6 @@ public:
   /// Requirements:
   ///
   ///  All elements in `Vals` must not be null.
-  ///
-  /// FIXME: Consider returning a model in case the conjunction of `Vals` is
-  /// satisfiable so that it can be used to generate warning messages.
   virtual Result solve(llvm::DenseSet<BoolValue *> Vals) = 0;
 };
 
diff --git a/clang/include/clang/Analysis/SelectorExtras.h b/clang/include/clang/Analysis/SelectorExtras.h
index 278f20e87cc6..1e1daf5706bb 100644
--- a/clang/include/clang/Analysis/SelectorExtras.h
+++ b/clang/include/clang/Analysis/SelectorExtras.h
@@ -16,7 +16,7 @@ namespace clang {
 template <typename... IdentifierInfos>
 static inline Selector getKeywordSelector(ASTContext &Ctx,
                                           IdentifierInfos *... IIs) {
-  static_assert(sizeof...(IdentifierInfos),
+  static_assert(sizeof...(IdentifierInfos) > 0,
                 "keyword selectors must have at least one argument");
   SmallVector<IdentifierInfo *, 10> II({&Ctx.Idents.get(IIs)...});
 
diff --git a/clang/include/clang/Basic/AlignedAllocation.h b/clang/include/clang/Basic/AlignedAllocation.h
index c1187b81420b..949e54c8c030 100644
--- a/clang/include/clang/Basic/AlignedAllocation.h
+++ b/clang/include/clang/Basic/AlignedAllocation.h
@@ -26,8 +26,8 @@ inline llvm::VersionTuple alignedAllocMinVersion(llvm::Triple::OSType OS) {
   default:
     break;
   case llvm::Triple::Darwin:
-  case llvm::Triple::MacOSX: // Earliest supporting version is 10.14.
-    return llvm::VersionTuple(10U, 14U);
+  case llvm::Triple::MacOSX: // Earliest supporting version is 10.13.
+    return llvm::VersionTuple(10U, 13U);
   case llvm::Triple::IOS:
   case llvm::Triple::TvOS: // Earliest supporting version is 11.0.0.
     return llvm::VersionTuple(11U);
diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
index cb47215f7e1d..78e0fce917a0 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -4036,3 +4036,14 @@ def NoRandomizeLayout : InheritableAttr {
   let LangOpts = [COnly];
 }
 def : MutualExclusions<[RandomizeLayout, NoRandomizeLayout]>;
+
+def FunctionReturnThunks : InheritableAttr,
+    TargetSpecificAttr<TargetAnyX86> {
+  let Spellings = [GCC<"function_return">];
+  let Args = [EnumArgument<"ThunkType", "Kind",
+    ["keep", "thunk-extern"],
+    ["Keep", "Extern"]
+  >];
+  let Subjects = SubjectList<[Function]>;
+  let Documentation = [FunctionReturnThunksDocs];
+}
diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
index 4e4d871a58a7..aff0dbbdd94d 100644
--- a/clang/include/clang/Basic/AttrDocs.td
+++ b/clang/include/clang/Basic/AttrDocs.td
@@ -3088,8 +3088,8 @@ def FormatDocs : Documentation {
   let Content = [{
 
 Clang supports the ``format`` attribute, which indicates that the function
-accepts a ``printf`` or ``scanf``-like format string and corresponding
-arguments or a ``va_list`` that contains these arguments.
+accepts (among other possibilities) a ``printf`` or ``scanf``-like format string
+and corresponding arguments or a ``va_list`` that contains these arguments.
 
 Please see `GCC documentation about format attribute
 <http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html>`_ to find details
@@ -3143,6 +3143,27 @@ Clang implements two kinds of checks with this attribute.
    In this case Clang does not warn because the format string ``s`` and
    the corresponding arguments are annotated. If the arguments are
    incorrect, the caller of ``foo`` will receive a warning.
+
+As an extension to GCC's behavior, Clang accepts the ``format`` attribute on
+non-variadic functions. Clang checks non-variadic format functions for the same
+classes of issues that can be found on variadic functions, as controlled by the
+same warning flags, except that the types of formatted arguments is forced by
+the function signature. For example:
+
+.. code-block:: c
+
+  __attribute__((__format__(__printf__, 1, 2)))
+  void fmt(const char *s, const char *a, int b);
+
+  void bar(void) {
+    fmt("%s %i", "hello", 123); // OK
+    fmt("%i %g", "hello", 123); // warning: arguments don't match format
+    extern const char *fmt;
+    fmt(fmt, "hello", 123); // warning: format string is not a string literal
+  }
+
+Using the ``format`` attribute on a non-variadic function emits a GCC
+compatibility diagnostic.
   }];
 }
 
@@ -6585,6 +6606,28 @@ evaluate to NULL.
       }
       return 0;
   }
+  }];
+}
+
+def FunctionReturnThunksDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+The attribute ``function_return`` can replace return instructions with jumps to
+target-specific symbols. This attribute supports 2 possible values,
+corresponding to the values supported by the ``-mfunction-return=`` command
+line flag:
+
+* ``__attribute__((function_return("keep")))`` to disable related transforms.
+  This is useful for undoing global setting from ``-mfunction-return=`` locally
+  for individual functions.
+* ``__attribute__((function_return("thunk-extern")))`` to replace returns with
+  jumps, while NOT emitting the thunk.
+
+The values ``thunk`` and ``thunk-inline`` from GCC are not supported.
+
+The symbol used for ``thunk-extern`` is target specific:
+* X86: ``__x86_return_thunk``
 
+As such, this function attribute is currently only supported on X86 targets.
   }];
 }
diff --git a/clang/include/clang/Basic/BuiltinsX86.def b/clang/include/clang/Basic/BuiltinsX86.def
index 3e5c376f9bc1..6bf35c340c2d 100644
--- a/clang/include/clang/Basic/BuiltinsX86.def
+++ b/clang/include/clang/Basic/BuiltinsX86.def
@@ -825,6 +825,7 @@ BUILTIN(__rdtsc, "UOi", "")
 BUILTIN(__builtin_ia32_rdtscp, "UOiUi*", "")
 
 TARGET_BUILTIN(__builtin_ia32_rdpid, "Ui", "n", "rdpid")
+TARGET_BUILTIN(__builtin_ia32_rdpru, "ULLii", "n", "rdpru")
 
 // PKU
 TARGET_BUILTIN(__builtin_ia32_rdpkru, "Ui", "n", "pku")
diff --git a/clang/include/clang/Basic/CodeGenOptions.def b/clang/include/clang/Basic/CodeGenOptions.def
index 72b0e5d8eb41..b1d394edd04a 100644
--- a/clang/include/clang/Basic/CodeGenOptions.def
+++ b/clang/include/clang/Basic/CodeGenOptions.def
@@ -107,6 +107,7 @@ CODEGENOPT(CFProtectionReturn , 1, 0) ///< if -fcf-protection is
 CODEGENOPT(CFProtectionBranch , 1, 0) ///< if -fcf-protection is
                                       ///< set to full or branch.
 CODEGENOPT(IBTSeal, 1, 0)             ///< set to optimize CFProtectionBranch.
+CODEGENOPT(FunctionReturnThunks, 1, 0) ///< -mfunction-return={keep|thunk-extern}
 
 CODEGENOPT(XRayInstrumentFunctions , 1, 0) ///< Set when -fxray-instrument is
                                            ///< enabled.
diff --git a/clang/include/clang/Basic/CodeGenOptions.h b/clang/include/clang/Basic/CodeGenOptions.h
index 23d76c308d84..cd204e5d7c15 100644
--- a/clang/include/clang/Basic/CodeGenOptions.h
+++ b/clang/include/clang/Basic/CodeGenOptions.h
@@ -389,6 +389,9 @@ public:
   /// On AArch64 this can only be "sp_el0".
   std::string StackProtectorGuardReg;
 
+  /// Specify a symbol to be the guard value.
+  std::string StackProtectorGuardSymbol;
+
   /// Path to ignorelist file specifying which objects
   /// (files, functions) listed for instrumentation by sanitizer
   /// coverage pass should actually not be instrumented.
diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
index 96219f83b0a5..68685baf7633 100644
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -60,8 +60,6 @@ def err_drv_no_cuda_libdevice : Error<
   "cannot find libdevice for %0; provide path to different CUDA installation "
   "via '--cuda-path', or pass '-nocudalib' to build without linking with "
   "libdevice">;
-def err_drv_no_rdc_new_driver : Error<
-  "Using '--offload-new-driver' requires '-fgpu-rdc'">;
 
 def err_drv_no_rocm_device_lib : Error<
   "cannot find ROCm device library%select{| for %1|for ABI version %1}0; provide its path via "
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 10da02ecbf7e..53e246a39ed8 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -31,6 +31,7 @@ def GNUAnonymousStruct : DiagGroup<"gnu-anonymous-struct">;
 def GNUAutoType : DiagGroup<"gnu-auto-type">;
 def ArrayBounds : DiagGroup<"array-bounds">;
 def ArrayBoundsPointerArithmetic : DiagGroup<"array-bounds-pointer-arithmetic">;
+def ArrayParameter : DiagGroup<"array-parameter">;
 def AutoDisableVptrSanitizer : DiagGroup<"auto-disable-vptr-sanitizer">;
 def Availability : DiagGroup<"availability">;
 def Section : DiagGroup<"section">;
@@ -187,6 +188,7 @@ def UnguardedAvailability : DiagGroup<"unguarded-availability",
 def : DiagGroup<"partial-availability", [UnguardedAvailability]>;
 def DeprecatedDynamicExceptionSpec
     : DiagGroup<"deprecated-dynamic-exception-spec">;
+def DeprecatedBuiltins : DiagGroup<"deprecated-builtins">;
 def DeprecatedImplementations :DiagGroup<"deprecated-implementations">;
 def DeprecatedIncrementBool : DiagGroup<"deprecated-increment-bool">;
 def DeprecatedRegister : DiagGroup<"deprecated-register">;
@@ -209,6 +211,7 @@ def Deprecated : DiagGroup<"deprecated", [DeprecatedAnonEnumEnumConversion,
                                           DeprecatedEnumCompareConditional,
                                           DeprecatedEnumEnumConversion,
                                           DeprecatedEnumFloatConversion,
+                                          DeprecatedBuiltins,
                                           DeprecatedIncrementBool,
                                           DeprecatedPragma,
                                           DeprecatedRegister,
@@ -978,6 +981,7 @@ def Extra : DiagGroup<"extra", [
   ]>;
 
 def Most : DiagGroup<"most", [
+    ArrayParameter,
     BoolOperation,
     CharSubscript,
     Comment,
diff --git a/clang/include/clang/Basic/DiagnosticLexKinds.td b/clang/include/clang/Basic/DiagnosticLexKinds.td
index ac86076140c5..dd0909704492 100644
--- a/clang/include/clang/Basic/DiagnosticLexKinds.td
+++ b/clang/include/clang/Basic/DiagnosticLexKinds.td
@@ -113,6 +113,8 @@ def warn_four_char_character_literal : Warning<
 // Unicode and UCNs
 def err_invalid_utf8 : Error<
   "source file is not valid UTF-8">;
+def warn_invalid_utf8_in_comment : Extension<
+  "invalid UTF-8 in comment">, InGroup<DiagGroup<"invalid-utf8">>;
 def err_character_not_allowed : Error<
   "unexpected character <U+%0>">;
 def err_character_not_allowed_identifier : Error<
@@ -128,8 +130,15 @@ def warn_utf8_symbol_zero_width : Warning<
   "some environments">, InGroup<DiagGroup<"unicode-zero-width">>;
 
 def ext_delimited_escape_sequence : Extension<
-  "%select{delimited|named}0 escape sequences are a Clang extension">,
+  "%select{delimited|named}0 escape sequences are a "
+  "%select{Clang|C++2b}1 extension">,
   InGroup<DiagGroup<"delimited-escape-sequence-extension">>;
+
+def warn_cxx2b_delimited_escape_sequence : Warning<
+  "%select{delimited|named}0 escape sequences are "
+  "incompatible with C++ standards before C++2b">,
+  InGroup<CXXPre2bCompat>, DefaultIgnore;
+
 def err_delimited_escape_empty : Error<
   "delimited escape sequence cannot be empty">;
 def err_delimited_escape_missing_brace: Error<
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index bc7aec3803e8..550029f58b54 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -3115,8 +3115,6 @@ def note_ownership_returns_index_mismatch : Note<
   "declared with index %0 here">;
 def err_format_strftime_third_parameter : Error<
   "strftime format attribute requires 3rd parameter to be 0">;
-def err_format_attribute_requires_variadic : Error<
-  "format attribute requires variadic function">;
 def err_format_attribute_not : Error<"format argument not a string type">;
 def err_format_attribute_result_not : Error<"function does not return %0">;
 def err_format_attribute_implicit_this_format_string : Error<
@@ -3343,10 +3341,11 @@ def warn_assume_aligned_too_great
               "alignment assumed">,
       InGroup<DiagGroup<"builtin-assume-aligned-alignment">>;
 def warn_not_xl_compatible
-    : Warning<"requesting an alignment of 16 bytes or greater for struct"
-              " members is not binary compatible with IBM XL C/C++ for AIX"
-              " 16.1.0 and older">,
+    : Warning<"alignment of 16 bytes for a struct member is not binary "
+              "compatible with IBM XL C/C++ for AIX 16.1.0 or older">,
       InGroup<AIXCompat>;
+def note_misaligned_member_used_here : Note<
+    "passing byval argument %0 with potentially incompatible alignment here">;
 def warn_redeclaration_without_attribute_prev_attribute_ignored : Warning<
   "%q0 redeclared without %1 attribute: previous %1 ignored">,
   InGroup<MicrosoftInconsistentDllImport>;
@@ -4127,6 +4126,9 @@ def err_attribute_not_supported_on_arch
 def warn_gcc_ignores_type_attr : Warning<
   "GCC does not allow the %0 attribute to be written on a type">,
   InGroup<GccCompat>;
+def warn_gcc_requires_variadic_function : Warning<
+  "GCC requires a function with the %0 attribute to be variadic">,
+  InGroup<GccCompat>;
 
 // Clang-Specific Attributes
 def warn_attribute_iboutlet : Warning<
@@ -4829,8 +4831,12 @@ def warn_cxx14_compat_template_nontype_parm_auto_type : Warning<
   DefaultIgnore, InGroup<CXXPre17Compat>;
 def err_template_param_default_arg_redefinition : Error<
   "template parameter redefines default argument">;
+def err_template_param_default_arg_inconsistent_redefinition : Error<
+  "template parameter default argument is inconsistent with previous definition">;
 def note_template_param_prev_default_arg : Note<
   "previous default template argument defined here">;
+def note_template_param_prev_default_arg_in_other_module : Note<
+  "previous default template argument defined in module %0">;
 def err_template_param_default_arg_missing : Error<
   "template parameter missing a default argument">;
 def ext_template_parameter_default_in_function_template : ExtWarn<
@@ -5557,6 +5563,9 @@ def warn_deprecated_def : Warning<
 def warn_unavailable_def : Warning<
   "implementing unavailable method">,
   InGroup<DeprecatedImplementations>, DefaultIgnore;
+def warn_deprecated_builtin : Warning<
+  "builtin %0 is deprecated; use %1 instead">,
+  InGroup<DeprecatedBuiltins>;
 def err_unavailable : Error<"%0 is unavailable">;
 def err_property_method_unavailable :
     Error<"property access is using %0 method which is unavailable">;
@@ -6605,13 +6614,16 @@ def warn_addition_in_bitshift : Warning<
   "'%1' will be evaluated first">, InGroup<ShiftOpParentheses>;
 
 def warn_self_assignment_builtin : Warning<
-  "explicitly assigning value of variable of type %0 to itself">,
+  "explicitly assigning value of variable of type %0 to itself%select{|; did "
+  "you mean to assign to member %2?}1">,
   InGroup<SelfAssignment>, DefaultIgnore;
 def warn_self_assignment_overloaded : Warning<
-  "explicitly assigning value of variable of type %0 to itself">,
+  "explicitly assigning value of variable of type %0 to itself%select{|; did "
+  "you mean to assign to member %2?}1">,
   InGroup<SelfAssignmentOverloaded>, DefaultIgnore;
 def warn_self_move : Warning<
-  "explicitly moving variable of type %0 to itself">,
+  "explicitly moving variable of type %0 to itself%select{|; did you mean to "
+  "move to member %2?}1">,
   InGroup<SelfMove>, DefaultIgnore;
 
 def err_builtin_move_forward_unsupported : Error<
@@ -9395,6 +9407,12 @@ def warn_array_index_exceeds_max_addressable_bounds : Warning<
 def note_array_declared_here : Note<
   "array %0 declared here">;
 
+def warn_inconsistent_array_form : Warning<
+  "argument %0 of type %1 with mismatched bound">,
+  InGroup<ArrayParameter>, DefaultIgnore;
+def note_previous_declaration_as : Note<
+  "previously declared as %0 here">;
+
 def warn_printf_insufficient_data_args : Warning<
   "more '%%' conversions than data arguments">, InGroup<FormatInsufficientArgs>;
 def warn_printf_data_arg_not_used : Warning<
diff --git a/clang/include/clang/Basic/MakeSupport.h b/clang/include/clang/Basic/MakeSupport.h
new file mode 100644
index 000000000000..c663014ba7bc
--- /dev/null
+++ b/clang/include/clang/Basic/MakeSupport.h
@@ -0,0 +1,23 @@
+//===- MakeSupport.h - Make Utilities ---------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_BASIC_MAKESUPPORT_H
+#define LLVM_CLANG_BASIC_MAKESUPPORT_H
+
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/StringRef.h"
+
+namespace clang {
+
+/// Quote target names for inclusion in GNU Make dependency files.
+/// Only the characters '$', '#', ' ', '\t' are quoted.
+void quoteMakeTarget(StringRef Target, SmallVectorImpl<char> &Res);
+
+} // namespace clang
+
+#endif // LLVM_CLANG_BASIC_MAKESUPPORT_H
diff --git a/clang/include/clang/Basic/TargetInfo.h b/clang/include/clang/Basic/TargetInfo.h
index 0ab3e9b67dfe..b4f3a69259fa 100644
--- a/clang/include/clang/Basic/TargetInfo.h
+++ b/clang/include/clang/Basic/TargetInfo.h
@@ -222,9 +222,7 @@ protected:
   mutable VersionTuple PlatformMinVersion;
 
   unsigned HasAlignMac68kSupport : 1;
-  unsigned RealTypeUsesObjCFPRetMask
-      : llvm::BitmaskEnumDetail::bitWidth(
-            (int)FloatModeKind::LLVM_BITMASK_LARGEST_ENUMERATOR);
+  unsigned RealTypeUsesObjCFPRetMask : llvm::BitWidth<FloatModeKind>;
   unsigned ComplexLongDoubleUsesFP2Ret : 1;
 
   unsigned HasBuiltinMSVaList : 1;
@@ -893,7 +891,7 @@ public:
   /// Check whether the given real type should use the "fpret" flavor of
   /// Objective-C message passing on this target.
   bool useObjCFPRetForRealType(FloatModeKind T) const {
-    return RealTypeUsesObjCFPRetMask & llvm::BitmaskEnumDetail::Underlying(T);
+    return (int)((FloatModeKind)RealTypeUsesObjCFPRetMask & T);
   }
 
   /// Check whether _Complex long double should use the "fp2ret" flavor
diff --git a/clang/include/clang/Basic/riscv_vector.td b/clang/include/clang/Basic/riscv_vector.td
index b11b780ec1f7..d96020ee40d0 100644
--- a/clang/include/clang/Basic/riscv_vector.td
+++ b/clang/include/clang/Basic/riscv_vector.td
@@ -582,18 +582,8 @@ class IsFloat<string type> {
 }
 
 let HasUnMaskedOverloaded = false,
-    MaskedPolicy = NonePolicy,
-    ManualCodegen = [{
-      IntrinsicTypes = {ResultType, Ops[1]->getType()};
-      Ops[0] = Builder.CreateBitCast(Ops[0], ResultType->getPointerTo());
-    }],
-    MaskedManualCodegen= [{
-      // Move mask to right before vl.
-      std::rotate(Ops.begin(), Ops.begin() + 1, Ops.end() - 1);
-      IntrinsicTypes = {ResultType, Ops[3]->getType()};
-      Ops[1] = Builder.CreateBitCast(Ops[1], ResultType->getPointerTo());
-    }] in {
-  class RVVVLEMaskBuiltin : RVVBuiltin<"m", "mPCUe", "c"> {
+    MaskedPolicy = NonePolicy in {
+  class RVVVLEMaskBuiltin : RVVOutBuiltin<"m", "mPCUe", "c"> {
     let Name = "vlm_v";
     let IRName = "vlm";
     let HasMasked = false;
@@ -601,26 +591,15 @@ let HasUnMaskedOverloaded = false,
 }
 
 let HasUnMaskedOverloaded = false,
-    ManualCodegen = [{
-      IntrinsicTypes = {ResultType, Ops[1]->getType()};
-      Ops[0] = Builder.CreateBitCast(Ops[0], ResultType->getPointerTo());
-      Ops.insert(Ops.begin(), llvm::UndefValue::get(ResultType));
-    }],
-    MaskedManualCodegen= [{
-      // Move mask to right before vl.
-      std::rotate(Ops.begin(), Ops.begin() + 1, Ops.end() - 1);
-      Ops.push_back(ConstantInt::get(Ops.back()->getType(), TAIL_UNDISTURBED));
-      IntrinsicTypes = {ResultType, Ops[3]->getType()};
-      Ops[1] = Builder.CreateBitCast(Ops[1], ResultType->getPointerTo());
-    }] in {
+    UnMaskedPolicy = HasPassthruOperand in {
   multiclass RVVVLEBuiltin<list<string> types> {
     let Name = NAME # "_v",
         IRName = "vle",
         MaskedIRName ="vle_mask" in {
       foreach type = types in {
-        def : RVVBuiltin<"v", "vPCe", type>;
+        def : RVVOutBuiltin<"v", "vPCe", type>;
         if !not(IsFloat<type>.val) then {
-          def : RVVBuiltin<"Uv", "UvPCUe", type>;
+          def : RVVOutBuiltin<"Uv", "UvPCUe", type>;
         }
       }
     }
@@ -685,61 +664,39 @@ multiclass RVVVLSEBuiltin<list<string> types> {
       IRName = "vlse",
       MaskedIRName ="vlse_mask",
       HasUnMaskedOverloaded = false,
-      ManualCodegen = [{
-        IntrinsicTypes = {ResultType, Ops[2]->getType()};
-        Ops[0] = Builder.CreateBitCast(Ops[0], ResultType->getPointerTo());
-        Ops.insert(Ops.begin(), llvm::UndefValue::get(ResultType));
-      }],
-      MaskedManualCodegen= [{
-        // Move mask to right before vl.
-        std::rotate(Ops.begin(), Ops.begin() + 1, Ops.end() - 1);
-        Ops.push_back(ConstantInt::get(Ops.back()->getType(), TAIL_UNDISTURBED));
-        IntrinsicTypes = {ResultType, Ops[4]->getType()};
-        Ops[1] = Builder.CreateBitCast(Ops[1], ResultType->getPointerTo());
-      }] in {
+      UnMaskedPolicy = HasPassthruOperand in {
     foreach type = types in {
-      def : RVVBuiltin<"v", "vPCet", type>;
+      def : RVVOutBuiltin<"v", "vPCet", type>;
       if !not(IsFloat<type>.val) then {
-        def : RVVBuiltin<"Uv", "UvPCUet", type>;
+        def : RVVOutBuiltin<"Uv", "UvPCUet", type>;
       }
     }
   }
 }
 
 multiclass RVVIndexedLoad<string op> {
-  let ManualCodegen = [{
-        IntrinsicTypes = {ResultType, Ops[1]->getType(), Ops[2]->getType()};
-        Ops[0] = Builder.CreateBitCast(Ops[0], ResultType->getPointerTo());
-        Ops.insert(Ops.begin(), llvm::UndefValue::get(ResultType));
-      }],
-      MaskedManualCodegen = [{
-        // Move mask to right before vl.
-        std::rotate(Ops.begin(), Ops.begin() + 1, Ops.end() - 1);
-        Ops.push_back(ConstantInt::get(Ops.back()->getType(), TAIL_UNDISTURBED));
-        IntrinsicTypes = {ResultType, Ops[2]->getType(), Ops[4]->getType()};
-        Ops[1] = Builder.CreateBitCast(Ops[1], ResultType->getPointerTo());
-      }] in {
-      foreach type = TypeList in {
-        foreach eew_list = EEWList[0-2] in {
-          defvar eew = eew_list[0];
-          defvar eew_type = eew_list[1];
-          let Name = op # eew # "_v", IRName = op, MaskedIRName = op # "_mask" in {
-            def: RVVBuiltin<"v", "vPCe" # eew_type # "Uv", type>;
-              if !not(IsFloat<type>.val) then {
-                def: RVVBuiltin<"Uv", "UvPCUe" # eew_type # "Uv", type>;
-              }
-          }
+  let UnMaskedPolicy = HasPassthruOperand in {
+    foreach type = TypeList in {
+      foreach eew_list = EEWList[0-2] in {
+        defvar eew = eew_list[0];
+        defvar eew_type = eew_list[1];
+        let Name = op # eew # "_v", IRName = op, MaskedIRName = op # "_mask" in {
+          def: RVVOutOp1Builtin<"v", "vPCe" # eew_type # "Uv", type>;
+            if !not(IsFloat<type>.val) then {
+              def: RVVOutOp1Builtin<"Uv", "UvPCUe" # eew_type # "Uv", type>;
+            }
         }
-        defvar eew64 = "64";
-        defvar eew64_type = "(Log2EEW:6)";
-        let Name = op # eew64 # "_v", IRName = op, MaskedIRName = op # "_mask",
-            RequiredFeatures = ["RV64"] in {
-            def: RVVBuiltin<"v", "vPCe" # eew64_type # "Uv", type>;
-              if !not(IsFloat<type>.val) then {
-                def: RVVBuiltin<"Uv", "UvPCUe" # eew64_type # "Uv", type>;
-              }
-          }
       }
+      defvar eew64 = "64";
+      defvar eew64_type = "(Log2EEW:6)";
+      let Name = op # eew64 # "_v", IRName = op, MaskedIRName = op # "_mask",
+          RequiredFeatures = ["RV64"] in {
+          def: RVVOutOp1Builtin<"v", "vPCe" # eew64_type # "Uv", type>;
+            if !not(IsFloat<type>.val) then {
+              def: RVVOutOp1Builtin<"Uv", "UvPCUe" # eew64_type # "Uv", type>;
+            }
+        }
+    }
   }
 }
 
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index f4fe08aa1a5b..532d7780c529 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1998,6 +1998,13 @@ def fcf_protection : Flag<["-"], "fcf-protection">, Group<f_Group>, Flags<[CoreO
   HelpText<"Enable cf-protection in 'full' mode">;
 def mibt_seal : Flag<["-"], "mibt-seal">, Group<m_Group>, Flags<[CoreOption, CC1Option]>,
   HelpText<"Optimize fcf-protection=branch/full (requires LTO).">;
+def mfunction_return_EQ : Joined<["-"], "mfunction-return=">,
+  Group<m_Group>, Flags<[CoreOption, CC1Option]>,
+  HelpText<"Replace returns with jumps to ``__x86_return_thunk`` (x86 only, error otherwise)">,
+  Values<"keep,thunk-extern">,
+  NormalizedValues<["Keep", "Extern"]>,
+  NormalizedValuesScope<"llvm::FunctionReturnThunksKind">,
+  MarshallingInfoEnum<CodeGenOpts<"FunctionReturnThunks">, "Keep">;
 
 defm xray_instrument : BoolFOption<"xray-instrument",
   LangOpts<"XRayInstrument">, DefaultFalse,
@@ -3338,11 +3345,12 @@ def mhwmult_EQ : Joined<["-"], "mhwmult=">, Group<m_Group>;
 def mglobal_merge : Flag<["-"], "mglobal-merge">, Group<m_Group>, Flags<[CC1Option]>,
   HelpText<"Enable merging of globals">;
 def mhard_float : Flag<["-"], "mhard-float">, Group<m_Group>;
-def miphoneos_version_min_EQ : Joined<["-"], "miphoneos-version-min=">, Group<m_Group>;
 def mios_version_min_EQ : Joined<["-"], "mios-version-min=">,
-  Alias<miphoneos_version_min_EQ>, HelpText<"Set iOS deployment target">;
+  Group<m_Group>, HelpText<"Set iOS deployment target">;
+def : Joined<["-"], "miphoneos-version-min=">,
+  Group<m_Group>, Alias<mios_version_min_EQ>;
 def mios_simulator_version_min_EQ : Joined<["-"], "mios-simulator-version-min=">;
-def miphonesimulator_version_min_EQ : Joined<["-"], "miphonesimulator-version-min=">, Alias<mios_simulator_version_min_EQ>;
+def : Joined<["-"], "miphonesimulator-version-min=">, Alias<mios_simulator_version_min_EQ>;
 def mkernel : Flag<["-"], "mkernel">, Group<m_Group>;
 def mlinker_version_EQ : Joined<["-"], "mlinker-version=">,
   Flags<[NoXarchOption]>;
@@ -3354,10 +3362,10 @@ def mmlir : Separate<["-"], "mmlir">, Flags<[CoreOption,FC1Option,FlangOption]>,
 def ffuchsia_api_level_EQ : Joined<["-"], "ffuchsia-api-level=">,
   Group<m_Group>, Flags<[CC1Option]>, HelpText<"Set Fuchsia API level">,
   MarshallingInfoInt<LangOpts<"FuchsiaAPILevel">>;
-def mmacosx_version_min_EQ : Joined<["-"], "mmacosx-version-min=">,
-  Group<m_Group>, HelpText<"Set Mac OS X deployment target">;
 def mmacos_version_min_EQ : Joined<["-"], "mmacos-version-min=">,
-  Group<m_Group>, Alias<mmacosx_version_min_EQ>;
+  Group<m_Group>, HelpText<"Set macOS deployment target">;
+def : Joined<["-"], "mmacosx-version-min=">,
+  Group<m_Group>, Alias<mmacos_version_min_EQ>;
 def mms_bitfields : Flag<["-"], "mms-bitfields">, Group<m_Group>, Flags<[CC1Option]>,
   HelpText<"Set the default structure layout to be compatible with the Microsoft compiler standard">,
   MarshallingInfoFlag<LangOpts<"MSBitfields">>;
@@ -3771,6 +3779,9 @@ def mstack_protector_guard_EQ : Joined<["-"], "mstack-protector-guard=">, Group<
 def mstack_protector_guard_offset_EQ : Joined<["-"], "mstack-protector-guard-offset=">, Group<m_Group>, Flags<[CC1Option]>,
   HelpText<"Use the given offset for addressing the stack-protector guard">,
   MarshallingInfoInt<CodeGenOpts<"StackProtectorGuardOffset">, "INT_MAX", "int">;
+def mstack_protector_guard_symbol_EQ : Joined<["-"], "mstack-protector-guard-symbol=">, Group<m_Group>, Flags<[CC1Option]>,
+  HelpText<"Use the given symbol for addressing the stack-protector guard">,
+  MarshallingInfoString<CodeGenOpts<"StackProtectorGuardSymbol">>;
 def mstack_protector_guard_reg_EQ : Joined<["-"], "mstack-protector-guard-reg=">, Group<m_Group>, Flags<[CC1Option]>,
   HelpText<"Use the given reg for addressing the stack-protector guard">,
   MarshallingInfoString<CodeGenOpts<"StackProtectorGuardReg">>;
@@ -3939,7 +3950,7 @@ def module_file_info : Flag<["-"], "module-file-info">, Flags<[NoXarchOption,CC1
   HelpText<"Provide information about a particular module file">;
 def mthumb : Flag<["-"], "mthumb">, Group<m_Group>;
 def mtune_EQ : Joined<["-"], "mtune=">, Group<m_Group>,
-  HelpText<"Only supported on X86 and RISC-V. Otherwise accepted for compatibility with GCC.">;
+  HelpText<"Only supported on X86, RISC-V and SystemZ. Otherwise accepted for compatibility with GCC.">;
 def multi__module : Flag<["-"], "multi_module">;
 def multiply__defined__unused : Separate<["-"], "multiply_defined_unused">;
 def multiply__defined : Separate<["-"], "multiply_defined">;
@@ -4570,6 +4581,8 @@ def mptwrite : Flag<["-"], "mptwrite">, Group<m_x86_Features_Group>;
 def mno_ptwrite : Flag<["-"], "mno-ptwrite">, Group<m_x86_Features_Group>;
 def mrdpid : Flag<["-"], "mrdpid">, Group<m_x86_Features_Group>;
 def mno_rdpid : Flag<["-"], "mno-rdpid">, Group<m_x86_Features_Group>;
+def mrdpru : Flag<["-"], "mrdpru">, Group<m_x86_Features_Group>;
+def mno_rdpru : Flag<["-"], "mno-rdpru">, Group<m_x86_Features_Group>;
 def mrdrnd : Flag<["-"], "mrdrnd">, Group<m_x86_Features_Group>;
 def mno_rdrnd : Flag<["-"], "mno-rdrnd">, Group<m_x86_Features_Group>;
 def mrtm : Flag<["-"], "mrtm">, Group<m_x86_Features_Group>;
diff --git a/clang/include/clang/Frontend/FrontendActions.h b/clang/include/clang/Frontend/FrontendActions.h
index ae829d741152..fe399850bd44 100644
--- a/clang/include/clang/Frontend/FrontendActions.h
+++ b/clang/include/clang/Frontend/FrontendActions.h
@@ -190,6 +190,10 @@ public:
 /// Dump information about the given module file, to be used for
 /// basic debugging and discovery.
 class DumpModuleInfoAction : public ASTFrontendAction {
+public:
+  // Allow other tools (ex lldb) to direct output for their use.
+  llvm::raw_ostream *OutputStream = nullptr;
+
 protected:
   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
                                                  StringRef InFile) override;
diff --git a/clang/include/clang/Lex/Preprocessor.h b/clang/include/clang/Lex/Preprocessor.h
index d130aba3ee3a..8fc24c731035 100644
--- a/clang/include/clang/Lex/Preprocessor.h
+++ b/clang/include/clang/Lex/Preprocessor.h
@@ -385,6 +385,7 @@ private:
 
     bool atTopLevel() { return S <= 0; }
     bool afterImportSeq() { return S == AfterImportSeq; }
+    bool afterTopLevelSeq() { return S == AfterTopLevelTokenSeq; }
 
   private:
     State S;
@@ -397,6 +398,67 @@ private:
   /// Our current position within a C++20 import-seq.
   ImportSeq ImportSeqState = ImportSeq::AfterTopLevelTokenSeq;
 
+  /// Track whether we are in a Global Module Fragment
+  class TrackGMF {
+  public:
+    enum GMFState : int {
+      GMFActive = 1,
+      MaybeGMF = 0,
+      BeforeGMFIntroducer = -1,
+      GMFAbsentOrEnded = -2,
+    };
+
+    TrackGMF(GMFState S) : S(S) {}
+
+    /// Saw a semicolon.
+    void handleSemi() {
+      // If it is immediately after the first instance of the module keyword,
+      // then that introduces the GMF.
+      if (S == MaybeGMF)
+        S = GMFActive;
+    }
+
+    /// Saw an 'export' identifier.
+    void handleExport() {
+      // The presence of an 'export' keyword always ends or excludes a GMF.
+      S = GMFAbsentOrEnded;
+    }
+
+    /// Saw an 'import' identifier.
+    void handleImport(bool AfterTopLevelTokenSeq) {
+      // If we see this before any 'module' kw, then we have no GMF.
+      if (AfterTopLevelTokenSeq && S == BeforeGMFIntroducer)
+        S = GMFAbsentOrEnded;
+    }
+
+    /// Saw a 'module' identifier.
+    void handleModule(bool AfterTopLevelTokenSeq) {
+      // This was the first module identifier and not preceded by any token
+      // that would exclude a GMF.  It could begin a GMF, but only if directly
+      // followed by a semicolon.
+      if (AfterTopLevelTokenSeq && S == BeforeGMFIntroducer)
+        S = MaybeGMF;
+      else
+        S = GMFAbsentOrEnded;
+    }
+
+    /// Saw any other token.
+    void handleMisc() {
+      // We saw something other than ; after the 'module' kw, so not a GMF.
+      if (S == MaybeGMF)
+        S = GMFAbsentOrEnded;
+    }
+
+    bool inGMF() { return S == GMFActive; }
+
+  private:
+    /// Track the transitions into and out of a Global Module Fragment,
+    /// if one is present.
+    GMFState S;
+  };
+
+  TrackGMF TrackGMFState = TrackGMF::BeforeGMFIntroducer;
+
   /// Whether the module import expects an identifier next. Otherwise,
   /// it expects a '.' or ';'.
   bool ModuleImportExpectsIdentifier = false;
@@ -2414,6 +2476,7 @@ private:
       None,
       ModuleBegin,
       ModuleImport,
+      HeaderUnitImport,
       SkippedModuleImport,
       Failure,
     } Kind;
diff --git a/clang/include/clang/Sema/HLSLExternalSemaSource.h b/clang/include/clang/Sema/HLSLExternalSemaSource.h
new file mode 100644
index 000000000000..439fc3d10f33
--- /dev/null
+++ b/clang/include/clang/Sema/HLSLExternalSemaSource.h
@@ -0,0 +1,41 @@
+//===--- HLSLExternalSemaSource.h - HLSL Sema Source ------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the HLSLExternalSemaSource interface.
+//
+//===----------------------------------------------------------------------===//
+#ifndef CLANG_SEMA_HLSLEXTERNALSEMASOURCE_H
+#define CLANG_SEMA_HLSLEXTERNALSEMASOURCE_H
+
+#include "clang/Sema/ExternalSemaSource.h"
+
+namespace clang {
+class NamespaceDecl;
+class Sema;
+
+class HLSLExternalSemaSource : public ExternalSemaSource {
+  Sema *SemaPtr = nullptr;
+  NamespaceDecl *HLSLNamespace;
+
+  void defineHLSLVectorAlias();
+
+public:
+  ~HLSLExternalSemaSource() override;
+
+  /// Initialize the semantic source with the Sema instance
+  /// being used to perform semantic analysis on the abstract syntax
+  /// tree.
+  void InitializeSema(Sema &S) override;
+
+  /// Inform the semantic consumer that Sema is no longer available.
+  void ForgetSema() override { SemaPtr = nullptr; }
+};
+
+} // namespace clang
+
+#endif // CLANG_SEMA_HLSLEXTERNALSEMASOURCE_H
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index ac241cf0515d..e51b9daef7d3 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -2272,6 +2272,9 @@ private:
 
   bool isAcceptableSlow(const NamedDecl *D, AcceptableKind Kind);
 
+  // Determine whether the module M belongs to the  current TU.
+  bool isModuleUnitOfCurrentTU(const Module *M) const;
+
 public:
   /// Get the module unit whose scope we are currently within.
   Module *getCurrentModule() const {
@@ -5167,6 +5170,11 @@ public:
   void DiagnoseSelfMove(const Expr *LHSExpr, const Expr *RHSExpr,
                         SourceLocation OpLoc);
 
+  /// Returns a field in a CXXRecordDecl that has the same name as the decl \p
+  /// SelfAssigned when inside a CXXMethodDecl.
+  const FieldDecl *
+  getSelfAssignmentClassMemberCandidate(const ValueDecl *SelfAssigned);
+
   /// Warn if we're implicitly casting from a _Nullable pointer type to a
   /// _Nonnull one.
   void diagnoseNullableToNonnullConversion(QualType DstType, QualType SrcType,
@@ -12997,21 +13005,29 @@ public:
   SourceLocation getLocationOfStringLiteralByte(const StringLiteral *SL,
                                                 unsigned ByteNo) const;
 
-private:
-  void CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
-                        const ArraySubscriptExpr *ASE=nullptr,
-                        bool AllowOnePastEnd=true, bool IndexNegated=false);
-  void CheckArrayAccess(const Expr *E);
+  enum FormatArgumentPassingKind {
+    FAPK_Fixed,    // values to format are fixed (no C-style variadic arguments)
+    FAPK_Variadic, // values to format are passed as variadic arguments
+    FAPK_VAList,   // values to format are passed in a va_list
+  };
+
   // Used to grab the relevant information from a FormatAttr and a
   // FunctionDeclaration.
   struct FormatStringInfo {
     unsigned FormatIdx;
     unsigned FirstDataArg;
-    bool HasVAListArg;
+    FormatArgumentPassingKind ArgPassingKind;
   };
 
   static bool getFormatStringInfo(const FormatAttr *Format, bool IsCXXMember,
-                                  FormatStringInfo *FSI);
+                                  bool IsVariadic, FormatStringInfo *FSI);
+
+private:
+  void CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
+                        const ArraySubscriptExpr *ASE = nullptr,
+                        bool AllowOnePastEnd = true, bool IndexNegated = false);
+  void CheckArrayAccess(const Expr *E);
+
   bool CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall,
                          const FunctionProtoType *Proto);
   bool CheckObjCMethodCall(ObjCMethodDecl *Method, SourceLocation loc,
@@ -13023,6 +13039,8 @@ private:
                             ArrayRef<const Expr *> Args,
                             const FunctionProtoType *Proto, SourceLocation Loc);
 
+  void checkAIXMemberAlignment(SourceLocation Loc, const Expr *Arg);
+
   void CheckArgAlignment(SourceLocation Loc, NamedDecl *FDecl,
                          StringRef ParamName, QualType ArgTy, QualType ParamTy);
 
@@ -13166,16 +13184,15 @@ public:
 
 private:
   bool CheckFormatArguments(const FormatAttr *Format,
-                            ArrayRef<const Expr *> Args,
-                            bool IsCXXMember,
-                            VariadicCallType CallType,
-                            SourceLocation Loc, SourceRange Range,
+                            ArrayRef<const Expr *> Args, bool IsCXXMember,
+                            VariadicCallType CallType, SourceLocation Loc,
+                            SourceRange Range,
                             llvm::SmallBitVector &CheckedVarArgs);
   bool CheckFormatArguments(ArrayRef<const Expr *> Args,
-                            bool HasVAListArg, unsigned format_idx,
+                            FormatArgumentPassingKind FAPK, unsigned format_idx,
                             unsigned firstDataArg, FormatStringType Type,
-                            VariadicCallType CallType,
-                            SourceLocation Loc, SourceRange range,
+                            VariadicCallType CallType, SourceLocation Loc,
+                            SourceRange range,
                             llvm::SmallBitVector &CheckedVarArgs);
 
   void CheckAbsoluteValueFunction(const CallExpr *Call,
diff --git a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h
index a01b32669ce3..50a27a211ef0 100644
--- a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h
+++ b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h
@@ -414,7 +414,8 @@ public:
   bool isArgumentConstructedDirectly(unsigned Index) const {
     // This assumes that the object was not yet removed from the state.
     return ExprEngine::getObjectUnderConstruction(
-        getState(), {getOriginExpr(), Index}, getLocationContext()).hasValue();
+               getState(), {getOriginExpr(), Index}, getLocationContext())
+        .has_value();
   }
 
   /// Some calls have parameter numbering mismatched from argument numbering.
@@ -1018,7 +1019,7 @@ public:
   SVal getObjectUnderConstruction() const {
     return ExprEngine::getObjectUnderConstruction(getState(), getOriginExpr(),
                                                   getLocationContext())
-        .getValue();
+        .value();
   }
 
   /// Number of non-placement arguments to the call. It is equal to 2 for
diff --git a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h
index 4b6cbd516628..22b405919bc1 100644
--- a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h
+++ b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h
@@ -53,21 +53,17 @@ public:
   }
 
   /// Return true if the constraint is perfectly constrained to 'true'.
-  bool isConstrainedTrue() const { return Val && Val.getValue(); }
+  bool isConstrainedTrue() const { return Val && Val.value(); }
 
   /// Return true if the constraint is perfectly constrained to 'false'.
-  bool isConstrainedFalse() const { return Val && !Val.getValue(); }
+  bool isConstrainedFalse() const { return Val && !Val.value(); }
 
   /// Return true if the constrained is perfectly constrained.
-  bool isConstrained() const {
-    return Val.hasValue();
-  }
+  bool isConstrained() const { return Val.has_value(); }
 
   /// Return true if the constrained is underconstrained and we do not know
   /// if the constraint is true of value.
-  bool isUnderconstrained() const {
-    return !Val.hasValue();
-  }
+  bool isUnderconstrained() const { return !Val.has_value(); }
 };
 
 class ConstraintManager {
diff --git a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/SMTConstraintManager.h b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/SMTConstraintManager.h
index 61cab28918db..cf515c5a809a 100644
--- a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/SMTConstraintManager.h
+++ b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/SMTConstraintManager.h
@@ -344,7 +344,7 @@ protected:
     if (!res)
       Cached[hash] = ConditionTruthVal();
     else
-      Cached[hash] = ConditionTruthVal(res.getValue());
+      Cached[hash] = ConditionTruthVal(res.value());
 
     return Cached[hash];
   }
diff --git a/clang/include/clang/Support/RISCVVIntrinsicUtils.h b/clang/include/clang/Support/RISCVVIntrinsicUtils.h
index 3b6f205f9f22..a5e7e6d35cc8 100644
--- a/clang/include/clang/Support/RISCVVIntrinsicUtils.h
+++ b/clang/include/clang/Support/RISCVVIntrinsicUtils.h
@@ -209,8 +209,8 @@ public:
   }
 
   bool isValid() const { return Valid; }
-  bool isScalar() const { return Scale && Scale.getValue() == 0; }
-  bool isVector() const { return Scale && Scale.getValue() != 0; }
+  bool isScalar() const { return Scale && Scale.value() == 0; }
+  bool isVector() const { return Scale && Scale.value() != 0; }
   bool isVector(unsigned Width) const {
     return isVector() && ElementBitwidth == Width;
   }
@@ -225,6 +225,8 @@ public:
     return isFloat() && ElementBitwidth == Width;
   }
 
+  bool isPointer() const { return IsPointer; }
+
 private:
   // Verify RVV vector type and set Valid.
   bool verifyType() const;
diff --git a/clang/include/clang/Tooling/DependencyScanning/DependencyScanningFilesystem.h b/clang/include/clang/Tooling/DependencyScanning/DependencyScanningFilesystem.h
index e0d16df92e1a..b3882c227eaf 100644
--- a/clang/include/clang/Tooling/DependencyScanning/DependencyScanningFilesystem.h
+++ b/clang/include/clang/Tooling/DependencyScanning/DependencyScanningFilesystem.h
@@ -94,9 +94,9 @@ public:
     assert(!isDirectory() && "not a file");
     assert(Contents && "contents not initialized");
     if (auto *Directives = Contents->DepDirectives.load()) {
-      if (Directives->hasValue())
+      if (Directives->has_value())
         return ArrayRef<dependency_directives_scan::Directive>(
-            Directives->getValue());
+            Directives->value());
     }
     return None;
   }
diff --git a/clang/include/clang/Tooling/DependencyScanning/DependencyScanningTool.h b/clang/include/clang/Tooling/DependencyScanning/DependencyScanningTool.h
index 3bb44e44187b..a85d333ba6b1 100644
--- a/clang/include/clang/Tooling/DependencyScanning/DependencyScanningTool.h
+++ b/clang/include/clang/Tooling/DependencyScanning/DependencyScanningTool.h
@@ -47,12 +47,12 @@ struct FullDependencies {
 
   /// Get the full command line.
   ///
-  /// \param LookupPCMPath This function is called to fill in "-fmodule-file="
-  ///                      arguments and the "-o" argument. It needs to return
-  ///                      a path for where the PCM for the given module is to
-  ///                      be located.
-  std::vector<std::string>
-  getCommandLine(std::function<StringRef(ModuleID)> LookupPCMPath) const;
+  /// \param LookupModuleOutput This function is called to fill in
+  ///                           "-fmodule-file=", "-o" and other output
+  ///                           arguments for dependencies.
+  std::vector<std::string> getCommandLine(
+      llvm::function_ref<std::string(const ModuleID &, ModuleOutputKind)>
+          LookupOutput) const;
 
   /// Get the full command line, excluding -fmodule-file=" arguments.
   std::vector<std::string> getCommandLineWithoutModulePaths() const;
diff --git a/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h b/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
index e0a4d6a554eb..05c9f56b4cf6 100644
--- a/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
+++ b/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
@@ -65,6 +65,19 @@ struct ModuleIDHasher {
   }
 };
 
+/// An output from a module compilation, such as the path of the module file.
+enum class ModuleOutputKind {
+  /// The module file (.pcm). Required.
+  ModuleFile,
+  /// The path of the dependency file (.d), if any.
+  DependencyFile,
+  /// The null-separated list of names to use as the targets in the dependency
+  /// file, if any. Defaults to the value of \c ModuleFile, as in the driver.
+  DependencyTargets,
+  /// The path of the serialized diagnostic file (.dia), if any.
+  DiagnosticSerializationFile,
+};
+
 struct ModuleDeps {
   /// The identifier of the module.
   ModuleID ID;
@@ -104,17 +117,25 @@ struct ModuleDeps {
   // the primary TU.
   bool ImportedByMainFile = false;
 
+  /// Whether the TU had a dependency file. The path in \c BuildInvocation is
+  /// cleared to avoid leaking the specific path from the TU into the module.
+  bool HadDependencyFile = false;
+
+  /// Whether the TU had serialized diagnostics. The path in \c BuildInvocation
+  /// is cleared to avoid leaking the specific path from the TU into the module.
+  bool HadSerializedDiagnostics = false;
+
   /// Compiler invocation that can be used to build this module (without paths).
   CompilerInvocation BuildInvocation;
 
   /// Gets the canonical command line suitable for passing to clang.
   ///
-  /// \param LookupPCMPath This function is called to fill in "-fmodule-file="
-  ///                      arguments and the "-o" argument. It needs to return
-  ///                      a path for where the PCM for the given module is to
-  ///                      be located.
+  /// \param LookupModuleOutput This function is called to fill in
+  ///                           "-fmodule-file=", "-o" and other output
+  ///                           arguments.
   std::vector<std::string> getCanonicalCommandLine(
-      std::function<StringRef(ModuleID)> LookupPCMPath) const;
+      llvm::function_ref<std::string(const ModuleID &, ModuleOutputKind)>
+          LookupModuleOutput) const;
 
   /// Gets the canonical command line suitable for passing to clang, excluding
   /// "-fmodule-file=" and "-o" arguments.
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 682b71a3d686..cfd7bf604542 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -3166,7 +3166,7 @@ void ASTContext::adjustDeducedFunctionResultType(FunctionDecl *FD,
 /// declaration of a function with an exception specification is permitted
 /// and preserved. Other type sugar (for instance, typedefs) is not.
 QualType ASTContext::getFunctionTypeWithExceptionSpec(
-    QualType Orig, const FunctionProtoType::ExceptionSpecInfo &ESI) {
+    QualType Orig, const FunctionProtoType::ExceptionSpecInfo &ESI) const {
   // Might have some parens.
   if (const auto *PT = dyn_cast<ParenType>(Orig))
     return getParenType(
@@ -3194,7 +3194,7 @@ QualType ASTContext::getFunctionTypeWithExceptionSpec(
 }
 
 bool ASTContext::hasSameFunctionTypeIgnoringExceptionSpec(QualType T,
-                                                          QualType U) {
+                                                          QualType U) const {
   return hasSameType(T, U) ||
          (getLangOpts().CPlusPlus17 &&
           hasSameType(getFunctionTypeWithExceptionSpec(T, EST_None),
@@ -4703,7 +4703,7 @@ QualType ASTContext::getUnresolvedUsingType(
 
 QualType ASTContext::getAttributedType(attr::Kind attrKind,
                                        QualType modifiedType,
-                                       QualType equivalentType) {
+                                       QualType equivalentType) const {
   llvm::FoldingSetNodeID id;
   AttributedType::Profile(id, attrKind, modifiedType, equivalentType);
 
@@ -5707,6 +5707,9 @@ QualType ASTContext::getAutoTypeInternal(
       !TypeConstraintConcept && !IsDependent)
     return getAutoDeductType();
 
+  if (TypeConstraintConcept)
+    TypeConstraintConcept = TypeConstraintConcept->getCanonicalDecl();
+
   // Look in the folding set for an existing type.
   void *InsertPos = nullptr;
   llvm::FoldingSetNodeID ID;
@@ -6215,8 +6218,59 @@ bool ASTContext::hasSameTemplateName(const TemplateName &X,
          getCanonicalTemplateName(Y).getAsVoidPointer();
 }
 
+bool ASTContext::isSameConstraintExpr(const Expr *XCE, const Expr *YCE) const {
+  if (!XCE != !YCE)
+    return false;
+
+  if (!XCE)
+    return true;
+
+  llvm::FoldingSetNodeID XCEID, YCEID;
+  XCE->Profile(XCEID, *this, /*Canonical=*/true);
+  YCE->Profile(YCEID, *this, /*Canonical=*/true);
+  return XCEID == YCEID;
+}
+
+bool ASTContext::isSameTypeConstraint(const TypeConstraint *XTC,
+                                      const TypeConstraint *YTC) const {
+  if (!XTC != !YTC)
+    return false;
+
+  if (!XTC)
+    return true;
+
+  auto *NCX = XTC->getNamedConcept();
+  auto *NCY = YTC->getNamedConcept();
+  if (!NCX || !NCY || !isSameEntity(NCX, NCY))
+    return false;
+  if (XTC->hasExplicitTemplateArgs() != YTC->hasExplicitTemplateArgs())
+    return false;
+  if (XTC->hasExplicitTemplateArgs())
+    if (XTC->getTemplateArgsAsWritten()->NumTemplateArgs !=
+        YTC->getTemplateArgsAsWritten()->NumTemplateArgs)
+      return false;
+
+  // Compare slowly by profiling.
+  //
+  // We couldn't compare the profiling result for the template
+  // args here. Consider the following example in different modules:
+  //
+  // template <__integer_like _Tp, C<_Tp> Sentinel>
+  // constexpr _Tp operator()(_Tp &&__t, Sentinel &&last) const {
+  //   return __t;
+  // }
+  //
+  // When we compare the profiling result for `C<_Tp>` in different
+  // modules, it will compare the type of `_Tp` in different modules.
+  // However, the type of `_Tp` in different modules refer to different
+  // types here naturally. So we couldn't compare the profiling result
+  // for the template args directly.
+  return isSameConstraintExpr(XTC->getImmediatelyDeclaredConstraint(),
+                              YTC->getImmediatelyDeclaredConstraint());
+}
+
 bool ASTContext::isSameTemplateParameter(const NamedDecl *X,
-                                         const NamedDecl *Y) {
+                                         const NamedDecl *Y) const {
   if (X->getKind() != Y->getKind())
     return false;
 
@@ -6226,32 +6280,8 @@ bool ASTContext::isSameTemplateParameter(const NamedDecl *X,
       return false;
     if (TX->hasTypeConstraint() != TY->hasTypeConstraint())
       return false;
-    const TypeConstraint *TXTC = TX->getTypeConstraint();
-    const TypeConstraint *TYTC = TY->getTypeConstraint();
-    if (!TXTC != !TYTC)
-      return false;
-    if (TXTC && TYTC) {
-      auto *NCX = TXTC->getNamedConcept();
-      auto *NCY = TYTC->getNamedConcept();
-      if (!NCX || !NCY || !isSameEntity(NCX, NCY))
-        return false;
-      if (TXTC->hasExplicitTemplateArgs() != TYTC->hasExplicitTemplateArgs())
-        return false;
-      if (TXTC->hasExplicitTemplateArgs()) {
-        auto *TXTCArgs = TXTC->getTemplateArgsAsWritten();
-        auto *TYTCArgs = TYTC->getTemplateArgsAsWritten();
-        if (TXTCArgs->NumTemplateArgs != TYTCArgs->NumTemplateArgs)
-          return false;
-        llvm::FoldingSetNodeID XID, YID;
-        for (auto &ArgLoc : TXTCArgs->arguments())
-          ArgLoc.getArgument().Profile(XID, X->getASTContext());
-        for (auto &ArgLoc : TYTCArgs->arguments())
-          ArgLoc.getArgument().Profile(YID, Y->getASTContext());
-        if (XID != YID)
-          return false;
-      }
-    }
-    return true;
+    return isSameTypeConstraint(TX->getTypeConstraint(),
+                                TY->getTypeConstraint());
   }
 
   if (auto *TX = dyn_cast<NonTypeTemplateParmDecl>(X)) {
@@ -6267,8 +6297,8 @@ bool ASTContext::isSameTemplateParameter(const NamedDecl *X,
                                      TY->getTemplateParameters());
 }
 
-bool ASTContext::isSameTemplateParameterList(const TemplateParameterList *X,
-                                             const TemplateParameterList *Y) {
+bool ASTContext::isSameTemplateParameterList(
+    const TemplateParameterList *X, const TemplateParameterList *Y) const {
   if (X->size() != Y->size())
     return false;
 
@@ -6276,19 +6306,46 @@ bool ASTContext::isSameTemplateParameterList(const TemplateParameterList *X,
     if (!isSameTemplateParameter(X->getParam(I), Y->getParam(I)))
       return false;
 
-  const Expr *XRC = X->getRequiresClause();
-  const Expr *YRC = Y->getRequiresClause();
-  if (!XRC != !YRC)
+  return isSameConstraintExpr(X->getRequiresClause(), Y->getRequiresClause());
+}
+
+bool ASTContext::isSameDefaultTemplateArgument(const NamedDecl *X,
+                                               const NamedDecl *Y) const {
+  // If the type parameter isn't the same already, we don't need to check the
+  // default argument further.
+  if (!isSameTemplateParameter(X, Y))
     return false;
-  if (XRC) {
-    llvm::FoldingSetNodeID XRCID, YRCID;
-    XRC->Profile(XRCID, *this, /*Canonical=*/true);
-    YRC->Profile(YRCID, *this, /*Canonical=*/true);
-    if (XRCID != YRCID)
+
+  if (auto *TTPX = dyn_cast<TemplateTypeParmDecl>(X)) {
+    auto *TTPY = cast<TemplateTypeParmDecl>(Y);
+    if (!TTPX->hasDefaultArgument() || !TTPY->hasDefaultArgument())
       return false;
+
+    return hasSameType(TTPX->getDefaultArgument(), TTPY->getDefaultArgument());
   }
 
-  return true;
+  if (auto *NTTPX = dyn_cast<NonTypeTemplateParmDecl>(X)) {
+    auto *NTTPY = cast<NonTypeTemplateParmDecl>(Y);
+    if (!NTTPX->hasDefaultArgument() || !NTTPY->hasDefaultArgument())
+      return false;
+
+    Expr *DefaultArgumentX = NTTPX->getDefaultArgument()->IgnoreImpCasts();
+    Expr *DefaultArgumentY = NTTPY->getDefaultArgument()->IgnoreImpCasts();
+    llvm::FoldingSetNodeID XID, YID;
+    DefaultArgumentX->Profile(XID, *this, /*Canonical=*/true);
+    DefaultArgumentY->Profile(YID, *this, /*Canonical=*/true);
+    return XID == YID;
+  }
+
+  auto *TTPX = cast<TemplateTemplateParmDecl>(X);
+  auto *TTPY = cast<TemplateTemplateParmDecl>(Y);
+
+  if (!TTPX->hasDefaultArgument() || !TTPY->hasDefaultArgument())
+    return false;
+
+  const TemplateArgument &TAX = TTPX->getDefaultArgument().getArgument();
+  const TemplateArgument &TAY = TTPY->getDefaultArgument().getArgument();
+  return hasSameTemplateName(TAX.getAsTemplate(), TAY.getAsTemplate());
 }
 
 static NamespaceDecl *getNamespace(const NestedNameSpecifier *X) {
@@ -6371,7 +6428,7 @@ static bool hasSameOverloadableAttrs(const FunctionDecl *A,
   return true;
 }
 
-bool ASTContext::isSameEntity(const NamedDecl *X, const NamedDecl *Y) {
+bool ASTContext::isSameEntity(const NamedDecl *X, const NamedDecl *Y) const {
   if (X == Y)
     return true;
 
@@ -6447,17 +6504,9 @@ bool ASTContext::isSameEntity(const NamedDecl *X, const NamedDecl *Y) {
         return false;
     }
 
-    const Expr *XRC = FuncX->getTrailingRequiresClause();
-    const Expr *YRC = FuncY->getTrailingRequiresClause();
-    if (!XRC != !YRC)
+    if (!isSameConstraintExpr(FuncX->getTrailingRequiresClause(),
+                              FuncY->getTrailingRequiresClause()))
       return false;
-    if (XRC) {
-      llvm::FoldingSetNodeID XRCID, YRCID;
-      XRC->Profile(XRCID, *this, /*Canonical=*/true);
-      YRC->Profile(YRCID, *this, /*Canonical=*/true);
-      if (XRCID != YRCID)
-        return false;
-    }
 
     auto GetTypeAsWritten = [](const FunctionDecl *FD) {
       // Map to the first declaration that we've already merged into this one.
@@ -6478,8 +6527,6 @@ bool ASTContext::isSameEntity(const NamedDecl *X, const NamedDecl *Y) {
       if (getLangOpts().CPlusPlus17 && XFPT && YFPT &&
           (isUnresolvedExceptionSpec(XFPT->getExceptionSpecType()) ||
            isUnresolvedExceptionSpec(YFPT->getExceptionSpecType())) &&
-          // FIXME: We could make isSameEntity const after we make
-          // hasSameFunctionTypeIgnoringExceptionSpec const.
           hasSameFunctionTypeIgnoringExceptionSpec(XT, YT))
         return true;
       return false;
@@ -6521,6 +6568,20 @@ bool ASTContext::isSameEntity(const NamedDecl *X, const NamedDecl *Y) {
   // and patterns match.
   if (const auto *TemplateX = dyn_cast<TemplateDecl>(X)) {
     const auto *TemplateY = cast<TemplateDecl>(Y);
+
+    // ConceptDecl wouldn't be the same if their constraint expression differs.
+    if (const auto *ConceptX = dyn_cast<ConceptDecl>(X)) {
+      const auto *ConceptY = cast<ConceptDecl>(Y);
+      const Expr *XCE = ConceptX->getConstraintExpr();
+      const Expr *YCE = ConceptY->getConstraintExpr();
+      assert(XCE && YCE && "ConceptDecl without constraint expression?");
+      llvm::FoldingSetNodeID XID, YID;
+      XCE->Profile(XID, *this, /*Canonical=*/true);
+      YCE->Profile(YID, *this, /*Canonical=*/true);
+      if (XID != YID)
+        return false;
+    }
+
     return isSameEntity(TemplateX->getTemplatedDecl(),
                         TemplateY->getTemplatedDecl()) &&
            isSameTemplateParameterList(TemplateX->getTemplateParameters(),
diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index e9730112eaa3..73c3f02e67a8 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -5667,11 +5667,6 @@ ExpectedDecl ASTNodeImporter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
     D2->setPreviousDecl(Recent);
   }
 
-  if (FromTemplated->isCompleteDefinition() &&
-      !ToTemplated->isCompleteDefinition()) {
-    // FIXME: Import definition!
-  }
-
   return D2;
 }
 
@@ -5950,11 +5945,6 @@ ExpectedDecl ASTNodeImporter::VisitVarTemplateDecl(VarTemplateDecl *D) {
     ToVarTD->setPreviousDecl(Recent);
   }
 
-  if (DTemplated->isThisDeclarationADefinition() &&
-      !ToTemplated->isThisDeclarationADefinition()) {
-    // FIXME: Import definition!
-  }
-
   return ToVarTD;
 }
 
diff --git a/clang/lib/AST/AttrImpl.cpp b/clang/lib/AST/AttrImpl.cpp
index c1e7435b22da..deb28bee5ed8 100644
--- a/clang/lib/AST/AttrImpl.cpp
+++ b/clang/lib/AST/AttrImpl.cpp
@@ -169,7 +169,7 @@ llvm::Optional<OMPDeclareTargetDeclAttr::MapTypeTy>
 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(const ValueDecl *VD) {
   llvm::Optional<OMPDeclareTargetDeclAttr *> ActiveAttr = getActiveAttr(VD);
   if (ActiveAttr)
-    return ActiveAttr.getValue()->getMapType();
+    return ActiveAttr.value()->getMapType();
   return llvm::None;
 }
 
@@ -177,7 +177,7 @@ llvm::Optional<OMPDeclareTargetDeclAttr::DevTypeTy>
 OMPDeclareTargetDeclAttr::getDeviceType(const ValueDecl *VD) {
   llvm::Optional<OMPDeclareTargetDeclAttr *> ActiveAttr = getActiveAttr(VD);
   if (ActiveAttr)
-    return ActiveAttr.getValue()->getDevType();
+    return ActiveAttr.value()->getDevType();
   return llvm::None;
 }
 
@@ -185,7 +185,7 @@ llvm::Optional<SourceLocation>
 OMPDeclareTargetDeclAttr::getLocation(const ValueDecl *VD) {
   llvm::Optional<OMPDeclareTargetDeclAttr *> ActiveAttr = getActiveAttr(VD);
   if (ActiveAttr)
-    return ActiveAttr.getValue()->getRange().getBegin();
+    return ActiveAttr.value()->getRange().getBegin();
   return llvm::None;
 }
 
diff --git a/clang/lib/AST/DeclPrinter.cpp b/clang/lib/AST/DeclPrinter.cpp
index c6a392c9c01b..3f04d9b4073e 100644
--- a/clang/lib/AST/DeclPrinter.cpp
+++ b/clang/lib/AST/DeclPrinter.cpp
@@ -1007,6 +1007,12 @@ void DeclPrinter::VisitCXXRecordDecl(CXXRecordDecl *D) {
     }
   }
 
+  if (auto *Def = D->getDefinition()) {
+      if (D->hasAttr<FinalAttr>()) {
+          Out << " final";
+      }
+  }
+
   if (D->isCompleteDefinition()) {
     // Print the base classes
     if (D->getNumBases()) {
diff --git a/clang/lib/AST/FormatString.cpp b/clang/lib/AST/FormatString.cpp
index 4977aaa51319..c0879704de4d 100644
--- a/clang/lib/AST/FormatString.cpp
+++ b/clang/lib/AST/FormatString.cpp
@@ -321,6 +321,12 @@ bool clang::analyze_format_string::ParseUTF8InvalidSpecifier(
 
 clang::analyze_format_string::ArgType::MatchKind
 ArgType::matchesType(ASTContext &C, QualType argTy) const {
+  // When using the format attribute in C++, you can receive a function or an
+  // array that will necessarily decay to a pointer when passed to the final
+  // format consumer. Apply decay before type comparison.
+  if (argTy->canDecayToPointerType())
+    argTy = C.getDecayedType(argTy);
+
   if (Ptr) {
     // It has to be a pointer.
     const PointerType *PT = argTy->getAs<PointerType>();
diff --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
index da538aa332ff..9b729e347a24 100644
--- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp
+++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
@@ -496,7 +496,7 @@ ByteCodeExprGen<Emitter>::getGlobalIdx(const VarDecl *VD) {
 
 template <class Emitter>
 const RecordType *ByteCodeExprGen<Emitter>::getRecordTy(QualType Ty) {
-  if (auto *PT = dyn_cast<PointerType>(Ty))
+  if (const PointerType *PT = dyn_cast<PointerType>(Ty))
     return PT->getPointeeType()->getAs<RecordType>();
   else
     return Ty->getAs<RecordType>();
diff --git a/clang/lib/Analysis/BodyFarm.cpp b/clang/lib/Analysis/BodyFarm.cpp
index 23d37b881069..38f100ae0a4f 100644
--- a/clang/lib/Analysis/BodyFarm.cpp
+++ b/clang/lib/Analysis/BodyFarm.cpp
@@ -699,7 +699,7 @@ static Stmt *create_OSAtomicCompareAndSwap(ASTContext &C, const FunctionDecl *D)
 Stmt *BodyFarm::getBody(const FunctionDecl *D) {
   Optional<Stmt *> &Val = Bodies[D];
   if (Val)
-    return Val.getValue();
+    return Val.value();
 
   Val = nullptr;
 
@@ -874,7 +874,7 @@ Stmt *BodyFarm::getBody(const ObjCMethodDecl *D) {
 
   Optional<Stmt *> &Val = Bodies[D];
   if (Val)
-    return Val.getValue();
+    return Val.value();
   Val = nullptr;
 
   // For now, we only synthesize getters.
diff --git a/clang/lib/Analysis/FlowSensitive/ControlFlowContext.cpp b/clang/lib/Analysis/FlowSensitive/ControlFlowContext.cpp
index fe9907a7c99b..58708b5b5efb 100644
--- a/clang/lib/Analysis/FlowSensitive/ControlFlowContext.cpp
+++ b/clang/lib/Analysis/FlowSensitive/ControlFlowContext.cpp
@@ -36,7 +36,7 @@ buildStmtToBasicBlockMap(const CFG &Cfg) {
       if (!Stmt)
         continue;
 
-      StmtToBlock[Stmt.getValue().getStmt()] = Block;
+      StmtToBlock[Stmt.value().getStmt()] = Block;
     }
     if (const Stmt *TerminatorStmt = Block->getTerminatorStmt())
       StmtToBlock[TerminatorStmt] = Block;
diff --git a/clang/lib/Analysis/FlowSensitive/DataflowAnalysisContext.cpp b/clang/lib/Analysis/FlowSensitive/DataflowAnalysisContext.cpp
index e08fc71c51dc..cd87e87a6aca 100644
--- a/clang/lib/Analysis/FlowSensitive/DataflowAnalysisContext.cpp
+++ b/clang/lib/Analysis/FlowSensitive/DataflowAnalysisContext.cpp
@@ -24,8 +24,8 @@ namespace dataflow {
 
 StorageLocation &
 DataflowAnalysisContext::getStableStorageLocation(QualType Type) {
-  assert(!Type.isNull());
-  if (Type->isStructureOrClassType() || Type->isUnionType()) {
+  if (!Type.isNull() &&
+      (Type->isStructureOrClassType() || Type->isUnionType())) {
     // FIXME: Explore options to avoid eager initialization of fields as some of
     // them might not be needed for a particular analysis.
     llvm::DenseMap<const ValueDecl *, StorageLocation *> FieldLocs;
@@ -57,8 +57,8 @@ DataflowAnalysisContext::getStableStorageLocation(const Expr &E) {
 
 PointerValue &
 DataflowAnalysisContext::getOrCreateNullPointerValue(QualType PointeeType) {
-  assert(!PointeeType.isNull());
-  auto CanonicalPointeeType = PointeeType.getCanonicalType();
+  auto CanonicalPointeeType =
+      PointeeType.isNull() ? PointeeType : PointeeType.getCanonicalType();
   auto Res = NullPointerVals.try_emplace(CanonicalPointeeType, nullptr);
   if (Res.second) {
     auto &PointeeLoc = getStableStorageLocation(CanonicalPointeeType);
diff --git a/clang/lib/Analysis/FlowSensitive/DebugSupport.cpp b/clang/lib/Analysis/FlowSensitive/DebugSupport.cpp
new file mode 100644
index 000000000000..305d9d346089
--- /dev/null
+++ b/clang/lib/Analysis/FlowSensitive/DebugSupport.cpp
@@ -0,0 +1,197 @@
+//===- DebugSupport.cpp -----------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines functions which generate more readable forms of data
+//  structures used in the dataflow analyses, for debugging purposes.
+//
+//===----------------------------------------------------------------------===//
+
+#include <utility>
+
+#include "clang/Analysis/FlowSensitive/DebugSupport.h"
+#include "clang/Analysis/FlowSensitive/Solver.h"
+#include "clang/Analysis/FlowSensitive/Value.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/FormatAdapters.h"
+#include "llvm/Support/FormatCommon.h"
+#include "llvm/Support/FormatVariadic.h"
+
+namespace clang {
+namespace dataflow {
+
+using llvm::AlignStyle;
+using llvm::fmt_pad;
+using llvm::formatv;
+
+namespace {
+
+class DebugStringGenerator {
+public:
+  explicit DebugStringGenerator(
+      llvm::DenseMap<const AtomicBoolValue *, std::string> AtomNamesArg)
+      : Counter(0), AtomNames(std::move(AtomNamesArg)) {
+#ifndef NDEBUG
+    llvm::StringSet<> Names;
+    for (auto &N : AtomNames) {
+      assert(Names.insert(N.second).second &&
+             "The same name must not assigned to different atoms");
+    }
+#endif
+  }
+
+  /// Returns a string representation of a boolean value `B`.
+  std::string debugString(const BoolValue &B, size_t Depth = 0) {
+    std::string S;
+    switch (B.getKind()) {
+    case Value::Kind::AtomicBool: {
+      S = getAtomName(&cast<AtomicBoolValue>(B));
+      break;
+    }
+    case Value::Kind::Conjunction: {
+      auto &C = cast<ConjunctionValue>(B);
+      auto L = debugString(C.getLeftSubValue(), Depth + 1);
+      auto R = debugString(C.getRightSubValue(), Depth + 1);
+      S = formatv("(and\n{0}\n{1})", L, R);
+      break;
+    }
+    case Value::Kind::Disjunction: {
+      auto &D = cast<DisjunctionValue>(B);
+      auto L = debugString(D.getLeftSubValue(), Depth + 1);
+      auto R = debugString(D.getRightSubValue(), Depth + 1);
+      S = formatv("(or\n{0}\n{1})", L, R);
+      break;
+    }
+    case Value::Kind::Negation: {
+      auto &N = cast<NegationValue>(B);
+      S = formatv("(not\n{0})", debugString(N.getSubVal(), Depth + 1));
+      break;
+    }
+    default:
+      llvm_unreachable("Unhandled value kind");
+    }
+    auto Indent = Depth * 4;
+    return formatv("{0}", fmt_pad(S, Indent, 0));
+  }
+
+  /// Returns a string representation of a set of boolean `Constraints` and the
+  /// `Result` of satisfiability checking on the `Constraints`.
+  std::string debugString(const std::vector<BoolValue *> &Constraints,
+                          const Solver::Result &Result) {
+    auto Template = R"(
+Constraints
+------------
+{0:$[
+
+]}
+------------
+{1}.
+{2}
+)";
+
+    std::vector<std::string> ConstraintsStrings;
+    ConstraintsStrings.reserve(Constraints.size());
+    for (auto &Constraint : Constraints) {
+      ConstraintsStrings.push_back(debugString(*Constraint));
+    }
+
+    auto StatusString = debugString(Result.getStatus());
+    auto Solution = Result.getSolution();
+    auto SolutionString =
+        Solution.hasValue() ? "\n" + debugString(Solution.value()) : "";
+
+    return formatv(
+        Template,
+        llvm::make_range(ConstraintsStrings.begin(), ConstraintsStrings.end()),
+        StatusString, SolutionString);
+  }
+
+private:
+  /// Returns a string representation of a truth assignment to atom booleans.
+  std::string debugString(
+      const llvm::DenseMap<AtomicBoolValue *, Solver::Result::Assignment>
+          &AtomAssignments) {
+    size_t MaxNameLength = 0;
+    for (auto &AtomName : AtomNames) {
+      MaxNameLength = std::max(MaxNameLength, AtomName.second.size());
+    }
+
+    std::vector<std::string> Lines;
+    for (auto &AtomAssignment : AtomAssignments) {
+      auto Line = formatv("{0} = {1}",
+                          fmt_align(getAtomName(AtomAssignment.first),
+                                    AlignStyle::Left, MaxNameLength),
+                          debugString(AtomAssignment.second));
+      Lines.push_back(Line);
+    }
+    llvm::sort(Lines.begin(), Lines.end());
+
+    return formatv("{0:$[\n]}", llvm::make_range(Lines.begin(), Lines.end()));
+  }
+
+  /// Returns a string representation of a boolean assignment to true or false.
+  std::string debugString(Solver::Result::Assignment Assignment) {
+    switch (Assignment) {
+    case Solver::Result::Assignment::AssignedFalse:
+      return "False";
+    case Solver::Result::Assignment::AssignedTrue:
+      return "True";
+    }
+    llvm_unreachable("Booleans can only be assigned true/false");
+  }
+
+  /// Returns a string representation of the result status of a SAT check.
+  std::string debugString(Solver::Result::Status Status) {
+    switch (Status) {
+    case Solver::Result::Status::Satisfiable:
+      return "Satisfiable";
+    case Solver::Result::Status::Unsatisfiable:
+      return "Unsatisfiable";
+    case Solver::Result::Status::TimedOut:
+      return "TimedOut";
+    }
+    llvm_unreachable("Unhandled SAT check result status");
+  }
+
+  /// Returns the name assigned to `Atom`, either user-specified or created by
+  /// default rules (B0, B1, ...).
+  std::string getAtomName(const AtomicBoolValue *Atom) {
+    auto Entry = AtomNames.try_emplace(Atom, formatv("B{0}", Counter));
+    if (Entry.second) {
+      Counter++;
+    }
+    return Entry.first->second;
+  }
+
+  // Keep track of number of atoms without a user-specified name, used to assign
+  // non-repeating default names to such atoms.
+  size_t Counter;
+
+  // Keep track of names assigned to atoms.
+  llvm::DenseMap<const AtomicBoolValue *, std::string> AtomNames;
+};
+
+} // namespace
+
+std::string
+debugString(const BoolValue &B,
+            llvm::DenseMap<const AtomicBoolValue *, std::string> AtomNames) {
+  return DebugStringGenerator(std::move(AtomNames)).debugString(B);
+}
+
+std::string
+debugString(const std::vector<BoolValue *> &Constraints,
+            const Solver::Result &Result,
+            llvm::DenseMap<const AtomicBoolValue *, std::string> AtomNames) {
+  return DebugStringGenerator(std::move(AtomNames))
+      .debugString(Constraints, Result);
+}
+
+} // namespace dataflow
+} // namespace clang
diff --git a/clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp b/clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp
index 6443fc1b6422..6ce9dd55914d 100644
--- a/clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp
+++ b/clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp
@@ -51,7 +51,7 @@ public:
     assert(BlockIT != CFCtx.getStmtToBlock().end());
     const auto &State = BlockToState[BlockIT->getSecond()->getBlockID()];
     assert(State);
-    return &State.getValue().Env;
+    return &State.value().Env;
   }
 
 private:
@@ -212,7 +212,7 @@ static TypeErasedDataflowAnalysisState computeBlockInputState(
     if (!MaybePredState)
       continue;
 
-    TypeErasedDataflowAnalysisState PredState = MaybePredState.getValue();
+    TypeErasedDataflowAnalysisState PredState = MaybePredState.value();
     if (ApplyBuiltinTransfer) {
       if (const Stmt *PredTerminatorStmt = Pred->getTerminatorStmt()) {
         const StmtToEnvMapImpl StmtToEnv(CFCtx, BlockStates);
@@ -370,7 +370,7 @@ runTypeErasedDataflowAnalysis(
         transferBlock(CFCtx, BlockStates, *Block, InitEnv, Analysis);
 
     if (OldBlockState &&
-        Analysis.isEqualTypeErased(OldBlockState.getValue().Lattice,
+        Analysis.isEqualTypeErased(OldBlockState.value().Lattice,
                                    NewBlockState.Lattice) &&
         OldBlockState->Env.equivalentTo(NewBlockState.Env, Analysis)) {
       // The state of `Block` didn't change after transfer so there's no need to
diff --git a/clang/lib/Analysis/FlowSensitive/WatchedLiteralsSolver.cpp b/clang/lib/Analysis/FlowSensitive/WatchedLiteralsSolver.cpp
index 0e6e70d6d5d4..6a3948bd1fea 100644
--- a/clang/lib/Analysis/FlowSensitive/WatchedLiteralsSolver.cpp
+++ b/clang/lib/Analysis/FlowSensitive/WatchedLiteralsSolver.cpp
@@ -120,7 +120,13 @@ struct BooleanFormula {
   /// clauses in the formula start from the element at index 1.
   std::vector<ClauseID> NextWatched;
 
-  explicit BooleanFormula(Variable LargestVar) : LargestVar(LargestVar) {
+  /// Stores the variable identifier and value location for atomic booleans in
+  /// the formula.
+  llvm::DenseMap<Variable, AtomicBoolValue *> Atomics;
+
+  explicit BooleanFormula(Variable LargestVar,
+                          llvm::DenseMap<Variable, AtomicBoolValue *> Atomics)
+      : LargestVar(LargestVar), Atomics(std::move(Atomics)) {
     Clauses.push_back(0);
     ClauseStarts.push_back(0);
     NextWatched.push_back(0);
@@ -180,28 +186,47 @@ BooleanFormula buildBooleanFormula(const llvm::DenseSet<BoolValue *> &Vals) {
 
   // Map each sub-value in `Vals` to a unique variable.
   llvm::DenseMap<BoolValue *, Variable> SubValsToVar;
+  // Store variable identifiers and value location of atomic booleans.
+  llvm::DenseMap<Variable, AtomicBoolValue *> Atomics;
   Variable NextVar = 1;
   {
     std::queue<BoolValue *> UnprocessedSubVals;
     for (BoolValue *Val : Vals)
       UnprocessedSubVals.push(Val);
     while (!UnprocessedSubVals.empty()) {
+      Variable Var = NextVar;
       BoolValue *Val = UnprocessedSubVals.front();
       UnprocessedSubVals.pop();
 
-      if (!SubValsToVar.try_emplace(Val, NextVar).second)
+      if (!SubValsToVar.try_emplace(Val, Var).second)
         continue;
       ++NextVar;
 
       // Visit the sub-values of `Val`.
-      if (auto *C = dyn_cast<ConjunctionValue>(Val)) {
+      switch (Val->getKind()) {
+      case Value::Kind::Conjunction: {
+        auto *C = cast<ConjunctionValue>(Val);
         UnprocessedSubVals.push(&C->getLeftSubValue());
         UnprocessedSubVals.push(&C->getRightSubValue());
-      } else if (auto *D = dyn_cast<DisjunctionValue>(Val)) {
+        break;
+      }
+      case Value::Kind::Disjunction: {
+        auto *D = cast<DisjunctionValue>(Val);
         UnprocessedSubVals.push(&D->getLeftSubValue());
         UnprocessedSubVals.push(&D->getRightSubValue());
-      } else if (auto *N = dyn_cast<NegationValue>(Val)) {
+        break;
+      }
+      case Value::Kind::Negation: {
+        auto *N = cast<NegationValue>(Val);
         UnprocessedSubVals.push(&N->getSubVal());
+        break;
+      }
+      case Value::Kind::AtomicBool: {
+        Atomics[Var] = cast<AtomicBoolValue>(Val);
+        break;
+      }
+      default:
+        llvm_unreachable("buildBooleanFormula: unhandled value kind");
       }
     }
   }
@@ -212,7 +237,7 @@ BooleanFormula buildBooleanFormula(const llvm::DenseSet<BoolValue *> &Vals) {
     return ValIt->second;
   };
 
-  BooleanFormula Formula(NextVar - 1);
+  BooleanFormula Formula(NextVar - 1, std::move(Atomics));
   std::vector<bool> ProcessedSubVals(NextVar, false);
 
   // Add a conjunct for each variable that represents a top-level conjunction
@@ -383,7 +408,7 @@ public:
         // If the root level is reached, then all possible assignments lead to
         // a conflict.
         if (Level == 0)
-          return WatchedLiteralsSolver::Result::Unsatisfiable;
+          return Solver::Result::Unsatisfiable();
 
         // Otherwise, take the other branch at the most recent level where a
         // decision was made.
@@ -440,12 +465,29 @@ public:
         ++I;
       }
     }
-    return WatchedLiteralsSolver::Result::Satisfiable;
+    return Solver::Result::Satisfiable(buildSolution());
   }
 
 private:
-  // Reverses forced moves until the most recent level where a decision was made
-  // on the assignment of a variable.
+  /// Returns a satisfying truth assignment to the atomic values in the boolean
+  /// formula.
+  llvm::DenseMap<AtomicBoolValue *, Solver::Result::Assignment>
+  buildSolution() {
+    llvm::DenseMap<AtomicBoolValue *, Solver::Result::Assignment> Solution;
+    for (auto &Atomic : Formula.Atomics) {
+      // A variable may have a definite true/false assignment, or it may be
+      // unassigned indicating its truth value does not affect the result of
+      // the formula. Unassigned variables are assigned to true as a default.
+      Solution[Atomic.second] =
+          VarAssignments[Atomic.first] == Assignment::AssignedFalse
+              ? Solver::Result::Assignment::AssignedFalse
+              : Solver::Result::Assignment::AssignedTrue;
+    }
+    return Solution;
+  }
+
+  /// Reverses forced moves until the most recent level where a decision was
+  /// made on the assignment of a variable.
   void reverseForcedMoves() {
     for (; LevelStates[Level] == State::Forced; --Level) {
       const Variable Var = LevelVars[Level];
@@ -459,7 +501,7 @@ private:
     }
   }
 
-  // Updates watched literals that are affected by a variable assignment.
+  /// Updates watched literals that are affected by a variable assignment.
   void updateWatchedLiterals() {
     const Variable Var = LevelVars[Level];
 
@@ -592,7 +634,7 @@ private:
 };
 
 Solver::Result WatchedLiteralsSolver::solve(llvm::DenseSet<BoolValue *> Vals) {
-  return Vals.empty() ? WatchedLiteralsSolver::Result::Satisfiable
+  return Vals.empty() ? Solver::Result::Satisfiable({{}})
                       : WatchedLiteralsSolverImpl(Vals).solve();
 }
 
diff --git a/clang/lib/Analysis/PathDiagnostic.cpp b/clang/lib/Analysis/PathDiagnostic.cpp
index 8a7305000746..bb5f116d6940 100644
--- a/clang/lib/Analysis/PathDiagnostic.cpp
+++ b/clang/lib/Analysis/PathDiagnostic.cpp
@@ -320,7 +320,7 @@ static Optional<bool> comparePath(const PathPieces &X, const PathPieces &Y) {
   for ( ; X_I != X_end && Y_I != Y_end; ++X_I, ++Y_I) {
     Optional<bool> b = comparePiece(**X_I, **Y_I);
     if (b)
-      return b.getValue();
+      return b.value();
   }
 
   return None;
@@ -397,7 +397,7 @@ static bool compare(const PathDiagnostic &X, const PathDiagnostic &Y) {
   }
   Optional<bool> b = comparePath(X.path, Y.path);
   assert(b);
-  return b.getValue();
+  return b.value();
 }
 
 void PathDiagnosticConsumer::FlushDiagnostics(
diff --git a/clang/lib/Analysis/UninitializedValues.cpp b/clang/lib/Analysis/UninitializedValues.cpp
index 800943a99d87..7f44685355e0 100644
--- a/clang/lib/Analysis/UninitializedValues.cpp
+++ b/clang/lib/Analysis/UninitializedValues.cpp
@@ -149,7 +149,7 @@ public:
                  const VarDecl *vd) {
     const Optional<unsigned> &idx = declToIndex.getValueIndex(vd);
     assert(idx);
-    return getValueVector(block)[idx.getValue()];
+    return getValueVector(block)[idx.value()];
   }
 };
 
@@ -210,7 +210,7 @@ void CFGBlockValues::resetScratch() {
 ValueVector::reference CFGBlockValues::operator[](const VarDecl *vd) {
   const Optional<unsigned> &idx = declToIndex.getValueIndex(vd);
   assert(idx);
-  return scratch[idx.getValue()];
+  return scratch[idx.value()];
 }
 
 //------------------------------------------------------------------------====//
diff --git a/clang/lib/Basic/LangStandards.cpp b/clang/lib/Basic/LangStandards.cpp
index 5bacc3b16496..a21898dd3c62 100644
--- a/clang/lib/Basic/LangStandards.cpp
+++ b/clang/lib/Basic/LangStandards.cpp
@@ -61,8 +61,8 @@ LangStandard::Kind clang::getDefaultLanguageStandard(clang::Language Lang,
     if (CLANG_DEFAULT_STD_C != LangStandard::lang_unspecified)
       return CLANG_DEFAULT_STD_C;
 
-    // The PS4 and PS5 use C99 as the default C standard.
-    if (T.isPS())
+    // The PS4 uses C99 as the default C standard.
+    if (T.isPS4())
       return LangStandard::lang_gnu99;
     return LangStandard::lang_gnu17;
   case Language::ObjC:
diff --git a/clang/lib/Basic/MakeSupport.cpp b/clang/lib/Basic/MakeSupport.cpp
new file mode 100644
index 000000000000..37838f7bbc7b
--- /dev/null
+++ b/clang/lib/Basic/MakeSupport.cpp
@@ -0,0 +1,35 @@
+//===-- MakeSuport.cpp --------------------------------------------------*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/MakeSupport.h"
+
+void clang::quoteMakeTarget(StringRef Target, SmallVectorImpl<char> &Res) {
+  for (unsigned i = 0, e = Target.size(); i != e; ++i) {
+    switch (Target[i]) {
+    case ' ':
+    case '\t':
+      // Escape the preceding backslashes
+      for (int j = i - 1; j >= 0 && Target[j] == '\\'; --j)
+        Res.push_back('\\');
+
+      // Escape the space/tab
+      Res.push_back('\\');
+      break;
+    case '$':
+      Res.push_back('$');
+      break;
+    case '#':
+      Res.push_back('\\');
+      break;
+    default:
+      break;
+    }
+
+    Res.push_back(Target[i]);
+  }
+}
\ No newline at end of file
diff --git a/clang/lib/Basic/TargetInfo.cpp b/clang/lib/Basic/TargetInfo.cpp
index e22ed34e7da4..6685145ea6d2 100644
--- a/clang/lib/Basic/TargetInfo.cpp
+++ b/clang/lib/Basic/TargetInfo.cpp
@@ -503,7 +503,7 @@ bool TargetInfo::initFeatureMap(
 TargetInfo::CallingConvKind
 TargetInfo::getCallingConvKind(bool ClangABICompat4) const {
   if (getCXXABI() != TargetCXXABI::Microsoft &&
-      (ClangABICompat4 || getTriple().getOS() == llvm::Triple::PS4))
+      (ClangABICompat4 || getTriple().isPS4()))
     return CCK_ClangABI4OrPS4;
   return CCK_Default;
 }
diff --git a/clang/lib/Basic/Targets/RISCV.cpp b/clang/lib/Basic/Targets/RISCV.cpp
index 32dd2bad2c5c..cb2cdb50e18e 100644
--- a/clang/lib/Basic/Targets/RISCV.cpp
+++ b/clang/lib/Basic/Targets/RISCV.cpp
@@ -252,7 +252,7 @@ bool RISCVTargetInfo::hasFeature(StringRef Feature) const {
                     .Case("64bit", Is64Bit)
                     .Default(None);
   if (Result)
-    return Result.getValue();
+    return Result.value();
 
   if (ISAInfo->isSupportedExtensionFeature(Feature))
     return ISAInfo->hasExtension(Feature);
diff --git a/clang/lib/Basic/Targets/SystemZ.h b/clang/lib/Basic/Targets/SystemZ.h
index d12045c756c1..e4f242e624cb 100644
--- a/clang/lib/Basic/Targets/SystemZ.h
+++ b/clang/lib/Basic/Targets/SystemZ.h
@@ -123,6 +123,14 @@ public:
 
   void fillValidCPUList(SmallVectorImpl<StringRef> &Values) const override;
 
+  bool isValidTuneCPUName(StringRef Name) const override {
+    return isValidCPUName(Name);
+  }
+
+  void fillValidTuneCPUList(SmallVectorImpl<StringRef> &Values) const override {
+    fillValidCPUList(Values);
+  }
+
   bool setCPU(const std::string &Name) override {
     CPU = Name;
     ISARevision = getISARevision(CPU);
diff --git a/clang/lib/Basic/Targets/X86.cpp b/clang/lib/Basic/Targets/X86.cpp
index 06988830eaed..69afdf8a3584 100644
--- a/clang/lib/Basic/Targets/X86.cpp
+++ b/clang/lib/Basic/Targets/X86.cpp
@@ -297,6 +297,8 @@ bool X86TargetInfo::handleTargetFeatures(std::vector<std::string> &Features,
       HasCLDEMOTE = true;
     } else if (Feature == "+rdpid") {
       HasRDPID = true;
+    } else if (Feature == "+rdpru") {
+      HasRDPRU = true;
     } else if (Feature == "+kl") {
       HasKL = true;
     } else if (Feature == "+widekl") {
@@ -743,6 +745,8 @@ void X86TargetInfo::getTargetDefines(const LangOptions &Opts,
     Builder.defineMacro("__WIDEKL__");
   if (HasRDPID)
     Builder.defineMacro("__RDPID__");
+  if (HasRDPRU)
+    Builder.defineMacro("__RDPRU__");
   if (HasCLDEMOTE)
     Builder.defineMacro("__CLDEMOTE__");
   if (HasWAITPKG)
@@ -926,6 +930,7 @@ bool X86TargetInfo::isValidFeatureName(StringRef Name) const {
       .Case("prfchw", true)
       .Case("ptwrite", true)
       .Case("rdpid", true)
+      .Case("rdpru", true)
       .Case("rdrnd", true)
       .Case("rdseed", true)
       .Case("rtm", true)
@@ -1021,6 +1026,7 @@ bool X86TargetInfo::hasFeature(StringRef Feature) const {
       .Case("prfchw", HasPRFCHW)
       .Case("ptwrite", HasPTWRITE)
       .Case("rdpid", HasRDPID)
+      .Case("rdpru", HasRDPRU)
       .Case("rdrnd", HasRDRND)
       .Case("rdseed", HasRDSEED)
       .Case("retpoline-external-thunk", HasRetpolineExternalThunk)
diff --git a/clang/lib/Basic/Targets/X86.h b/clang/lib/Basic/Targets/X86.h
index 78e444f4e4eb..ea98dcf42de6 100644
--- a/clang/lib/Basic/Targets/X86.h
+++ b/clang/lib/Basic/Targets/X86.h
@@ -125,6 +125,7 @@ class LLVM_LIBRARY_VISIBILITY X86TargetInfo : public TargetInfo {
   bool HasMOVBE = false;
   bool HasPREFETCHWT1 = false;
   bool HasRDPID = false;
+  bool HasRDPRU = false;
   bool HasRetpolineExternalThunk = false;
   bool HasLAHFSAHF = false;
   bool HasWBNOINVD = false;
@@ -420,8 +421,8 @@ public:
 
     // Use fpret for all types.
     RealTypeUsesObjCFPRetMask =
-        (int)(FloatModeKind::Float | FloatModeKind::Double |
-              FloatModeKind::LongDouble);
+        (unsigned)(FloatModeKind::Float | FloatModeKind::Double |
+                   FloatModeKind::LongDouble);
 
     // x86-32 has atomics up to 8 bytes
     MaxAtomicPromoteWidth = 64;
@@ -700,7 +701,7 @@ public:
                                         "64-i64:64-f80:128-n8:16:32:64-S128");
 
     // Use fpret only for long double.
-    RealTypeUsesObjCFPRetMask = (int)FloatModeKind::LongDouble;
+    RealTypeUsesObjCFPRetMask = (unsigned)FloatModeKind::LongDouble;
 
     // Use fp2ret for _Complex long double.
     ComplexLongDoubleUsesFP2Ret = true;
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index eb40e446057f..7c4e35634e5d 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -788,6 +788,18 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
   SI.registerCallbacks(PIC, &FAM);
   PassBuilder PB(TM.get(), PTO, PGOOpt, &PIC);
 
+  // Enable verify-debuginfo-preserve-each for new PM.
+  DebugifyEachInstrumentation Debugify;
+  DebugInfoPerPass DebugInfoBeforePass;
+  if (CodeGenOpts.EnableDIPreservationVerify) {
+    Debugify.setDebugifyMode(DebugifyMode::OriginalDebugInfo);
+    Debugify.setDebugInfoBeforePass(DebugInfoBeforePass);
+
+    if (!CodeGenOpts.DIBugsReportFilePath.empty())
+      Debugify.setOrigDIVerifyBugsReportFilePath(
+          CodeGenOpts.DIBugsReportFilePath);
+    Debugify.registerCallbacks(PIC);
+  }
   // Attempt to load pass plugins and register their callbacks with PB.
   for (auto &PluginFN : CodeGenOpts.PassPlugins) {
     auto PassPlugin = PassPlugin::Load(PluginFN);
diff --git a/clang/lib/CodeGen/CGCUDANV.cpp b/clang/lib/CodeGen/CGCUDANV.cpp
index 6f2679cb15e4..a8bb0dd65d1a 100644
--- a/clang/lib/CodeGen/CGCUDANV.cpp
+++ b/clang/lib/CodeGen/CGCUDANV.cpp
@@ -212,8 +212,7 @@ static std::unique_ptr<MangleContext> InitDeviceMC(CodeGenModule &CGM) {
 CGNVCUDARuntime::CGNVCUDARuntime(CodeGenModule &CGM)
     : CGCUDARuntime(CGM), Context(CGM.getLLVMContext()),
       TheModule(CGM.getModule()),
-      RelocatableDeviceCode(CGM.getLangOpts().GPURelocatableDeviceCode ||
-                            CGM.getLangOpts().OffloadingNewDriver),
+      RelocatableDeviceCode(CGM.getLangOpts().GPURelocatableDeviceCode),
       DeviceMC(InitDeviceMC(CGM)) {
   CodeGen::CodeGenTypes &Types = CGM.getTypes();
   ASTContext &Ctx = CGM.getContext();
@@ -1116,7 +1115,8 @@ void CGNVCUDARuntime::createOffloadingEntries() {
   llvm::OpenMPIRBuilder OMPBuilder(CGM.getModule());
   OMPBuilder.initialize();
 
-  StringRef Section = "cuda_offloading_entries";
+  StringRef Section = CGM.getLangOpts().HIP ? "hip_offloading_entries"
+                                            : "cuda_offloading_entries";
   for (KernelInfo &I : EmittedKernels)
     OMPBuilder.emitOffloadingEntry(KernelHandles[I.Kernel],
                                    getDeviceSideName(cast<NamedDecl>(I.D)), 0,
@@ -1171,10 +1171,11 @@ llvm::Function *CGNVCUDARuntime::finalizeModule() {
     }
     return nullptr;
   }
-  if (!(CGM.getLangOpts().OffloadingNewDriver && RelocatableDeviceCode))
+  if (CGM.getLangOpts().OffloadingNewDriver && RelocatableDeviceCode)
+    createOffloadingEntries();
+  else
     return makeModuleCtorFunction();
 
-  createOffloadingEntries();
   return nullptr;
 }
 
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 4e26c35c6342..104a30dd6b25 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -1931,6 +1931,9 @@ void CodeGenModule::getDefaultFunctionAttributes(StringRef Name,
     FuncAttrs.addAttribute(llvm::Attribute::Convergent);
   }
 
+  // TODO: NoUnwind attribute should be added for other GPU modes OpenCL, HIP,
+  // SYCL, OpenMP offload. AFAIK, none of them support exceptions in device
+  // code.
   if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
     // Exceptions aren't supported in CUDA device code.
     FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
diff --git a/clang/lib/CodeGen/CGClass.cpp b/clang/lib/CodeGen/CGClass.cpp
index 153f299a1c4b..cde31711a7db 100644
--- a/clang/lib/CodeGen/CGClass.cpp
+++ b/clang/lib/CodeGen/CGClass.cpp
@@ -1783,14 +1783,14 @@ namespace {
          StartIndex = FieldIndex;
      } else if (StartIndex) {
        EHStack.pushCleanup<SanitizeDtorFieldRange>(
-           NormalAndEHCleanup, DD, StartIndex.getValue(), FieldIndex);
+           NormalAndEHCleanup, DD, StartIndex.value(), FieldIndex);
        StartIndex = None;
      }
    }
    void End() {
      if (StartIndex)
        EHStack.pushCleanup<SanitizeDtorFieldRange>(NormalAndEHCleanup, DD,
-                                                   StartIndex.getValue(), -1);
+                                                   StartIndex.value(), -1);
    }
  };
 } // end anonymous namespace
diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.cpp b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
index 305040b01c08..091eb9da5af4 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -6717,11 +6717,9 @@ llvm::Value *CGOpenMPRuntime::emitNumTeamsForTargetDirective(
     default:
       break;
     }
-  } else if (DefaultNT == -1) {
-    return nullptr;
   }
 
-  return Bld.getInt32(DefaultNT);
+  return llvm::ConstantInt::get(CGF.Int32Ty, DefaultNT);
 }
 
 static llvm::Value *getNumThreads(CodeGenFunction &CGF, const CapturedStmt *CS,
@@ -10189,9 +10187,8 @@ llvm::Function *CGOpenMPRuntime::getOrCreateUserDefinedMapperFunc(
   return UDMMap.lookup(D);
 }
 
-void CGOpenMPRuntime::emitTargetNumIterationsCall(
+llvm::Value *CGOpenMPRuntime::emitTargetNumIterationsCall(
     CodeGenFunction &CGF, const OMPExecutableDirective &D,
-    llvm::Value *DeviceID,
     llvm::function_ref<llvm::Value *(CodeGenFunction &CGF,
                                      const OMPLoopDirective &D)>
         SizeEmitter) {
@@ -10201,20 +10198,12 @@ void CGOpenMPRuntime::emitTargetNumIterationsCall(
   if (!isOpenMPDistributeDirective(Kind) || !isOpenMPTeamsDirective(Kind))
     TD = getNestedDistributeDirective(CGM.getContext(), D);
   if (!TD)
-    return;
+    return llvm::ConstantInt::get(CGF.Int64Ty, 0);
+
   const auto *LD = cast<OMPLoopDirective>(TD);
-  auto &&CodeGen = [LD, DeviceID, SizeEmitter, &D, this](CodeGenFunction &CGF,
-                                                         PrePostActionTy &) {
-    if (llvm::Value *NumIterations = SizeEmitter(CGF, *LD)) {
-      llvm::Value *RTLoc = emitUpdateLocation(CGF, D.getBeginLoc());
-      llvm::Value *Args[] = {RTLoc, DeviceID, NumIterations};
-      CGF.EmitRuntimeCall(
-          OMPBuilder.getOrCreateRuntimeFunction(
-              CGM.getModule(), OMPRTL___kmpc_push_target_tripcount_mapper),
-          Args);
-    }
-  };
-  emitInlinedDirective(CGF, OMPD_unknown, CodeGen);
+  if (llvm::Value *NumIterations = SizeEmitter(CGF, *LD))
+    return NumIterations;
+  return llvm::ConstantInt::get(CGF.Int64Ty, 0);
 }
 
 void CGOpenMPRuntime::emitTargetCall(
@@ -10308,26 +10297,34 @@ void CGOpenMPRuntime::emitTargetCall(
     // Source location for the ident struct
     llvm::Value *RTLoc = emitUpdateLocation(CGF, D.getBeginLoc());
 
-    // Emit tripcount for the target loop-based directive.
-    emitTargetNumIterationsCall(CGF, D, DeviceID, SizeEmitter);
+    // Get tripcount for the target loop-based directive.
+    llvm::Value *NumIterations =
+        emitTargetNumIterationsCall(CGF, D, SizeEmitter);
+
+    // Arguments for the target kernel.
+    SmallVector<llvm::Value *> KernelArgs{
+        CGF.Builder.getInt32(/* Version */ 1),
+        PointerNum,
+        InputInfo.BasePointersArray.getPointer(),
+        InputInfo.PointersArray.getPointer(),
+        InputInfo.SizesArray.getPointer(),
+        MapTypesArray,
+        MapNamesArray,
+        InputInfo.MappersArray.getPointer(),
+        NumIterations};
+
+    // Arguments passed to the 'nowait' variant.
+    SmallVector<llvm::Value *> NoWaitKernelArgs{
+        CGF.Builder.getInt32(0),
+        llvm::ConstantPointerNull::get(CGM.VoidPtrTy),
+        CGF.Builder.getInt32(0),
+        llvm::ConstantPointerNull::get(CGM.VoidPtrTy),
+    };
+
+    bool HasNoWait = D.hasClausesOfKind<OMPNowaitClause>();
 
-    bool HasNowait = D.hasClausesOfKind<OMPNowaitClause>();
     // The target region is an outlined function launched by the runtime
-    // via calls __tgt_target() or __tgt_target_teams().
-    //
-    // __tgt_target() launches a target region with one team and one thread,
-    // executing a serial region.  This master thread may in turn launch
-    // more threads within its team upon encountering a parallel region,
-    // however, no additional teams can be launched on the device.
-    //
-    // __tgt_target_teams() launches a target region with one or more teams,
-    // each with one or more threads.  This call is required for target
-    // constructs such as:
-    //  'target teams'
-    //  'target' / 'teams'
-    //  'target teams distribute parallel for'
-    //  'target parallel'
-    // and so on.
+    // via calls to __tgt_target_kernel().
     //
     // Note that on the host and CPU targets, the runtime implementation of
     // these calls simply call the outlined function without forking threads.
@@ -10338,70 +10335,15 @@ void CGOpenMPRuntime::emitTargetCall(
     // In contrast, on the NVPTX target, the implementation of
     // __tgt_target_teams() launches a GPU kernel with the requested number
     // of teams and threads so no additional calls to the runtime are required.
-    if (NumTeams) {
-      // If we have NumTeams defined this means that we have an enclosed teams
-      // region. Therefore we also expect to have NumThreads defined. These two
-      // values should be defined in the presence of a teams directive,
-      // regardless of having any clauses associated. If the user is using teams
-      // but no clauses, these two values will be the default that should be
-      // passed to the runtime library - a 32-bit integer with the value zero.
-      assert(NumThreads && "Thread limit expression should be available along "
-                           "with number of teams.");
-      SmallVector<llvm::Value *> OffloadingArgs = {
-          RTLoc,
-          DeviceID,
-          OutlinedFnID,
-          PointerNum,
-          InputInfo.BasePointersArray.getPointer(),
-          InputInfo.PointersArray.getPointer(),
-          InputInfo.SizesArray.getPointer(),
-          MapTypesArray,
-          MapNamesArray,
-          InputInfo.MappersArray.getPointer(),
-          NumTeams,
-          NumThreads};
-      if (HasNowait) {
-        // Add int32_t depNum = 0, void *depList = nullptr, int32_t
-        // noAliasDepNum = 0, void *noAliasDepList = nullptr.
-        OffloadingArgs.push_back(CGF.Builder.getInt32(0));
-        OffloadingArgs.push_back(llvm::ConstantPointerNull::get(CGM.VoidPtrTy));
-        OffloadingArgs.push_back(CGF.Builder.getInt32(0));
-        OffloadingArgs.push_back(llvm::ConstantPointerNull::get(CGM.VoidPtrTy));
-      }
-      Return = CGF.EmitRuntimeCall(
-          OMPBuilder.getOrCreateRuntimeFunction(
-              CGM.getModule(), HasNowait
-                                   ? OMPRTL___tgt_target_teams_nowait_mapper
-                                   : OMPRTL___tgt_target_teams_mapper),
-          OffloadingArgs);
-    } else {
-      SmallVector<llvm::Value *> OffloadingArgs = {
-          RTLoc,
-          DeviceID,
-          OutlinedFnID,
-          PointerNum,
-          InputInfo.BasePointersArray.getPointer(),
-          InputInfo.PointersArray.getPointer(),
-          InputInfo.SizesArray.getPointer(),
-          MapTypesArray,
-          MapNamesArray,
-          InputInfo.MappersArray.getPointer()};
-      if (HasNowait) {
-        // Add int32_t depNum = 0, void *depList = nullptr, int32_t
-        // noAliasDepNum = 0, void *noAliasDepList = nullptr.
-        OffloadingArgs.push_back(CGF.Builder.getInt32(0));
-        OffloadingArgs.push_back(llvm::ConstantPointerNull::get(CGM.VoidPtrTy));
-        OffloadingArgs.push_back(CGF.Builder.getInt32(0));
-        OffloadingArgs.push_back(llvm::ConstantPointerNull::get(CGM.VoidPtrTy));
-      }
-      Return = CGF.EmitRuntimeCall(
-          OMPBuilder.getOrCreateRuntimeFunction(
-              CGM.getModule(), HasNowait ? OMPRTL___tgt_target_nowait_mapper
-                                         : OMPRTL___tgt_target_mapper),
-          OffloadingArgs);
-    }
-
     // Check the error code and execute the host version if required.
+    CGF.Builder.restoreIP(
+        HasNoWait ? OMPBuilder.emitTargetKernel(
+                        CGF.Builder, Return, RTLoc, DeviceID, NumTeams,
+                        NumThreads, OutlinedFnID, KernelArgs, NoWaitKernelArgs)
+                  : OMPBuilder.emitTargetKernel(CGF.Builder, Return, RTLoc,
+                                                DeviceID, NumTeams, NumThreads,
+                                                OutlinedFnID, KernelArgs));
+
     llvm::BasicBlock *OffloadFailedBlock =
         CGF.createBasicBlock("omp_offload.failed");
     llvm::BasicBlock *OffloadContBlock =
diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.h b/clang/lib/CodeGen/CGOpenMPRuntime.h
index 7fc6a7e278e5..b95aef68335e 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.h
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.h
@@ -884,13 +884,11 @@ private:
                             llvm::Function *TaskFunction, QualType SharedsTy,
                             Address Shareds, const OMPTaskDataTy &Data);
 
-  /// Emit code that pushes the trip count of loops associated with constructs
-  /// 'target teams distribute' and 'teams distribute parallel for'.
-  /// \param SizeEmitter Emits the int64 value for the number of iterations of
-  /// the associated loop.
-  void emitTargetNumIterationsCall(
+  /// Return the trip count of loops associated with constructs / 'target teams
+  /// distribute' and 'teams distribute parallel for'. \param SizeEmitter Emits
+  /// the int64 value for the number of iterations of the associated loop.
+  llvm::Value *emitTargetNumIterationsCall(
       CodeGenFunction &CGF, const OMPExecutableDirective &D,
-      llvm::Value *DeviceID,
       llvm::function_ref<llvm::Value *(CodeGenFunction &CGF,
                                        const OMPLoopDirective &D)>
           SizeEmitter);
diff --git a/clang/lib/CodeGen/CGStmtOpenMP.cpp b/clang/lib/CodeGen/CGStmtOpenMP.cpp
index 301f5278df69..db0b2ffd3a4f 100644
--- a/clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/clang/lib/CodeGen/CGStmtOpenMP.cpp
@@ -2591,11 +2591,12 @@ static void emitOMPSimdRegion(CodeGenFunction &CGF, const OMPLoopDirective &S,
   }
 }
 
-static bool isSupportedByOpenMPIRBuilder(const OMPExecutableDirective &S) {
+static bool isSupportedByOpenMPIRBuilder(const OMPSimdDirective &S) {
   // Check for unsupported clauses
-  if (!S.clauses().empty()) {
-    // Currently no clause is supported
-    return false;
+  for (OMPClause *C : S.clauses()) {
+    // Currently only simdlen clause is supported
+    if (!isa<OMPSimdlenClause>(C))
+      return false;
   }
 
   // Check if we have a statement with the ordered directive.
@@ -2630,7 +2631,6 @@ void CodeGenFunction::EmitOMPSimdDirective(const OMPSimdDirective &S) {
       // Use the OpenMPIRBuilder if enabled.
       if (UseOMPIRBuilder) {
         // Emit the associated statement and get its loop representation.
-        llvm::DebugLoc DL = SourceLocToDebugLoc(S.getBeginLoc());
         const Stmt *Inner = S.getRawStmt();
         llvm::CanonicalLoopInfo *CLI =
             EmitOMPCollapsedCanonicalLoopNest(Inner, 1);
@@ -2638,7 +2638,15 @@ void CodeGenFunction::EmitOMPSimdDirective(const OMPSimdDirective &S) {
         llvm::OpenMPIRBuilder &OMPBuilder =
             CGM.getOpenMPRuntime().getOMPBuilder();
         // Add SIMD specific metadata
-        OMPBuilder.applySimd(DL, CLI);
+        llvm::ConstantInt *Simdlen = nullptr;
+        if (const auto *C = S.getSingleClause<OMPSimdlenClause>()) {
+          RValue Len =
+              this->EmitAnyExpr(C->getSimdlen(), AggValueSlot::ignored(),
+                                /*ignoreResult=*/true);
+          auto *Val = cast<llvm::ConstantInt>(Len.getScalarVal());
+          Simdlen = Val;
+        }
+        OMPBuilder.applySimd(CLI, Simdlen);
         return;
       }
     };
@@ -5998,18 +6006,26 @@ static std::pair<bool, RValue> emitOMPAtomicRMW(CodeGenFunction &CGF, LValue X,
     RMWOp = llvm::AtomicRMWInst::Xor;
     break;
   case BO_LT:
-    RMWOp = X.getType()->hasSignedIntegerRepresentation()
-                ? (IsXLHSInRHSPart ? llvm::AtomicRMWInst::Min
-                                   : llvm::AtomicRMWInst::Max)
-                : (IsXLHSInRHSPart ? llvm::AtomicRMWInst::UMin
-                                   : llvm::AtomicRMWInst::UMax);
+    if (IsInteger)
+      RMWOp = X.getType()->hasSignedIntegerRepresentation()
+                  ? (IsXLHSInRHSPart ? llvm::AtomicRMWInst::Min
+                                     : llvm::AtomicRMWInst::Max)
+                  : (IsXLHSInRHSPart ? llvm::AtomicRMWInst::UMin
+                                     : llvm::AtomicRMWInst::UMax);
+    else
+      RMWOp = IsXLHSInRHSPart ? llvm::AtomicRMWInst::FMin
+                              : llvm::AtomicRMWInst::FMax;
     break;
   case BO_GT:
-    RMWOp = X.getType()->hasSignedIntegerRepresentation()
-                ? (IsXLHSInRHSPart ? llvm::AtomicRMWInst::Max
-                                   : llvm::AtomicRMWInst::Min)
-                : (IsXLHSInRHSPart ? llvm::AtomicRMWInst::UMax
-                                   : llvm::AtomicRMWInst::UMin);
+    if (IsInteger)
+      RMWOp = X.getType()->hasSignedIntegerRepresentation()
+                  ? (IsXLHSInRHSPart ? llvm::AtomicRMWInst::Max
+                                     : llvm::AtomicRMWInst::Min)
+                  : (IsXLHSInRHSPart ? llvm::AtomicRMWInst::UMax
+                                     : llvm::AtomicRMWInst::UMin);
+    else
+      RMWOp = IsXLHSInRHSPart ? llvm::AtomicRMWInst::FMax
+                              : llvm::AtomicRMWInst::FMin;
     break;
   case BO_Assign:
     RMWOp = llvm::AtomicRMWInst::Xchg;
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 05942f462dd1..17c1c91c7e8f 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -898,6 +898,20 @@ void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
   if (D && D->hasAttr<NoProfileFunctionAttr>())
     Fn->addFnAttr(llvm::Attribute::NoProfile);
 
+  if (D) {
+    // Function attributes take precedence over command line flags.
+    if (auto *A = D->getAttr<FunctionReturnThunksAttr>()) {
+      switch (A->getThunkType()) {
+      case FunctionReturnThunksAttr::Kind::Keep:
+        break;
+      case FunctionReturnThunksAttr::Kind::Extern:
+        Fn->addFnAttr(llvm::Attribute::FnRetThunkExtern);
+        break;
+      }
+    } else if (CGM.getCodeGenOpts().FunctionReturnThunks)
+      Fn->addFnAttr(llvm::Attribute::FnRetThunkExtern);
+  }
+
   if (FD && (getLangOpts().OpenCL ||
              (getLangOpts().HIP && getLangOpts().CUDAIsDevice))) {
     // Add metadata for a kernel function.
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 56ed59d1e3f1..c372bab1eccb 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -445,6 +445,7 @@ void CodeGenModule::checkAliases() {
 
 void CodeGenModule::clear() {
   DeferredDeclsToEmit.clear();
+  EmittedDeferredDecls.clear();
   if (OpenMPRuntime)
     OpenMPRuntime->clear();
 }
@@ -510,6 +511,9 @@ static void setVisibilityFromDLLStorageClass(const clang::LangOptions &LO,
 
 void CodeGenModule::Release() {
   EmitDeferred();
+  DeferredDecls.insert(EmittedDeferredDecls.begin(),
+                       EmittedDeferredDecls.end());
+  EmittedDeferredDecls.clear();
   EmitVTablesOpportunistically();
   applyGlobalValReplacements();
   applyReplacements();
@@ -900,6 +904,9 @@ void CodeGenModule::Release() {
   if (!getCodeGenOpts().StackProtectorGuardReg.empty())
     getModule().setStackProtectorGuardReg(
         getCodeGenOpts().StackProtectorGuardReg);
+  if (!getCodeGenOpts().StackProtectorGuardSymbol.empty())
+    getModule().setStackProtectorGuardSymbol(
+        getCodeGenOpts().StackProtectorGuardSymbol);
   if (getCodeGenOpts().StackProtectorGuardOffset != INT_MAX)
     getModule().setStackProtectorGuardOffset(
         getCodeGenOpts().StackProtectorGuardOffset);
@@ -4286,6 +4293,9 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
       getCUDARuntime().handleVarRegistration(D, *GV);
   }
 
+  if (D)
+    SanitizerMD->reportGlobal(GV, *D);
+
   LangAS ExpectedAS =
       D ? D->getType().getAddressSpace()
         : (LangOpts.OpenCL ? LangAS::opencl_global : LangAS::Default);
diff --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index da43b9616c88..10b49da27dab 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -344,6 +344,20 @@ private:
   std::vector<GlobalDecl> DeferredDeclsToEmit;
   void addDeferredDeclToEmit(GlobalDecl GD) {
     DeferredDeclsToEmit.emplace_back(GD);
+    addEmittedDeferredDecl(GD);
+  }
+
+  /// Decls that were DeferredDecls and have now been emitted.
+  llvm::DenseMap<llvm::StringRef, GlobalDecl> EmittedDeferredDecls;
+
+  void addEmittedDeferredDecl(GlobalDecl GD) {
+    if (!llvm::isa<FunctionDecl>(GD.getDecl()))
+      return;
+    llvm::GlobalVariable::LinkageTypes L = getFunctionLinkage(GD);
+    if (llvm::GlobalValue::isLinkOnceLinkage(L) ||
+        llvm::GlobalValue::isWeakLinkage(L)) {
+      EmittedDeferredDecls[getMangledName(GD)] = GD;
+    }
   }
 
   /// List of alias we have emitted. Used to make sure that what they point to
@@ -1516,6 +1530,11 @@ public:
     NewBuilder->WeakRefReferences = std::move(WeakRefReferences);
 
     NewBuilder->TBAA = std::move(TBAA);
+
+    assert(NewBuilder->EmittedDeferredDecls.empty() &&
+           "Still have (unmerged) EmittedDeferredDecls deferred decls");
+
+    NewBuilder->EmittedDeferredDecls = std::move(EmittedDeferredDecls);
   }
 
 private:
diff --git a/clang/lib/CodeGen/CodeGenTBAA.cpp b/clang/lib/CodeGen/CodeGenTBAA.cpp
index 95763d8e18b7..0cb63fbbe9e5 100644
--- a/clang/lib/CodeGen/CodeGenTBAA.cpp
+++ b/clang/lib/CodeGen/CodeGenTBAA.cpp
@@ -335,7 +335,42 @@ llvm::MDNode *CodeGenTBAA::getBaseTypeInfoHelper(const Type *Ty) {
   if (auto *TTy = dyn_cast<RecordType>(Ty)) {
     const RecordDecl *RD = TTy->getDecl()->getDefinition();
     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
-    SmallVector<llvm::MDBuilder::TBAAStructField, 4> Fields;
+    using TBAAStructField = llvm::MDBuilder::TBAAStructField;
+    SmallVector<TBAAStructField, 4> Fields;
+    if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
+      // Handle C++ base classes. Non-virtual bases can treated a a kind of
+      // field. Virtual bases are more complex and omitted, but avoid an
+      // incomplete view for NewStructPathTBAA.
+      if (CodeGenOpts.NewStructPathTBAA && CXXRD->getNumVBases() != 0)
+        return BaseTypeMetadataCache[Ty] = nullptr;
+      for (const CXXBaseSpecifier &B : CXXRD->bases()) {
+        if (B.isVirtual())
+          continue;
+        QualType BaseQTy = B.getType();
+        const CXXRecordDecl *BaseRD = BaseQTy->getAsCXXRecordDecl();
+        if (BaseRD->isEmpty())
+          continue;
+        llvm::MDNode *TypeNode = isValidBaseType(BaseQTy)
+                                     ? getBaseTypeInfo(BaseQTy)
+                                     : getTypeInfo(BaseQTy);
+        if (!TypeNode)
+          return BaseTypeMetadataCache[Ty] = nullptr;
+        uint64_t Offset = Layout.getBaseClassOffset(BaseRD).getQuantity();
+        uint64_t Size =
+            Context.getASTRecordLayout(BaseRD).getDataSize().getQuantity();
+        Fields.push_back(
+            llvm::MDBuilder::TBAAStructField(Offset, Size, TypeNode));
+      }
+      // The order in which base class subobjects are allocated is unspecified,
+      // so may differ from declaration order. In particular, Itanium ABI will
+      // allocate a primary base first.
+      // Since we exclude empty subobjects, the objects are not overlapping and
+      // their offsets are unique.
+      llvm::sort(Fields,
+                 [](const TBAAStructField &A, const TBAAStructField &B) {
+                   return A.Offset < B.Offset;
+                 });
+    }
     for (FieldDecl *Field : RD->fields()) {
       if (Field->isZeroSize(Context) || Field->isUnnamedBitfield())
         continue;
diff --git a/clang/lib/CodeGen/SanitizerMetadata.cpp b/clang/lib/CodeGen/SanitizerMetadata.cpp
index 5f4eb9be981f..7848cf012633 100644
--- a/clang/lib/CodeGen/SanitizerMetadata.cpp
+++ b/clang/lib/CodeGen/SanitizerMetadata.cpp
@@ -60,17 +60,17 @@ void SanitizerMetadata::reportGlobal(llvm::GlobalVariable *GV,
   Meta.NoHWAddress |= CGM.isInNoSanitizeList(
       FsanitizeArgument.Mask & SanitizerKind::HWAddress, GV, Loc, Ty);
 
-  Meta.NoMemtag |= NoSanitizeAttrSet.hasOneOf(SanitizerKind::MemTag);
-  Meta.NoMemtag |= CGM.isInNoSanitizeList(
+  Meta.Memtag |=
+      static_cast<bool>(FsanitizeArgument.Mask & SanitizerKind::MemtagGlobals);
+  Meta.Memtag &= !NoSanitizeAttrSet.hasOneOf(SanitizerKind::MemTag);
+  Meta.Memtag &= !CGM.isInNoSanitizeList(
       FsanitizeArgument.Mask & SanitizerKind::MemTag, GV, Loc, Ty);
 
-  if (FsanitizeArgument.has(SanitizerKind::Address)) {
-    // TODO(hctim): Make this conditional when we migrate off llvm.asan.globals.
-    IsDynInit &= !CGM.isInNoSanitizeList(SanitizerKind::Address |
-                                             SanitizerKind::KernelAddress,
-                                         GV, Loc, Ty, "init");
-    Meta.IsDynInit = IsDynInit;
-  }
+  Meta.IsDynInit = IsDynInit && !Meta.NoAddress &&
+                   FsanitizeArgument.has(SanitizerKind::Address) &&
+                   !CGM.isInNoSanitizeList(SanitizerKind::Address |
+                                               SanitizerKind::KernelAddress,
+                                           GV, Loc, Ty, "init");
 
   GV->setSanitizerMetadata(Meta);
 }
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 0da32dae2ef6..3a8400a55741 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -2930,7 +2930,7 @@ class OffloadingActionBuilder final {
         return false;
 
       Relocatable = Args.hasFlag(options::OPT_fgpu_rdc,
-          options::OPT_fno_gpu_rdc, /*Default=*/false);
+                                 options::OPT_fno_gpu_rdc, /*Default=*/false);
 
       const ToolChain *HostTC = C.getSingleOffloadToolChain<Action::OFK_Host>();
       assert(HostTC && "No toolchain for host compilation.");
@@ -3326,7 +3326,7 @@ class OffloadingActionBuilder final {
                                                AssociatedOffloadKind);
 
       if (CompileDeviceOnly && CurPhase == FinalPhase && BundleOutput &&
-          BundleOutput.getValue()) {
+          BundleOutput.value()) {
         for (unsigned I = 0, E = GpuArchList.size(); I != E; ++I) {
           OffloadAction::DeviceDependences DDep;
           DDep.add(*CudaDeviceActions[I], *ToolChains.front(), GpuArchList[I],
@@ -4355,7 +4355,17 @@ Driver::getOffloadArchs(Compilation &C, const llvm::opt::DerivedArgList &Args,
     return KnownArchs.lookup(TC);
 
   llvm::DenseSet<StringRef> Archs;
-  for (auto &Arg : Args) {
+  for (auto *Arg : Args) {
+    // Extract any '--[no-]offload-arch' arguments intended for this toolchain.
+    std::unique_ptr<llvm::opt::Arg> ExtractedArg = nullptr;
+    if (Arg->getOption().matches(options::OPT_Xopenmp_target_EQ) &&
+        ToolChain::getOpenMPTriple(Arg->getValue(0)) == TC->getTriple()) {
+      Arg->claim();
+      unsigned Index = Args.getBaseArgs().MakeIndex(Arg->getValue(1));
+      ExtractedArg = getOpts().ParseOneArg(Args, Index);
+      Arg = ExtractedArg.get();
+    }
+
     if (Arg->getOption().matches(options::OPT_offload_arch_EQ)) {
       for (StringRef Arch : llvm::split(Arg->getValue(), ","))
         Archs.insert(getCanonicalArchString(C, Args, Arch, TC->getTriple()));
@@ -4425,8 +4435,7 @@ Action *Driver::BuildOffloadingActions(Compilation &C,
     // Get the product of all bound architectures and toolchains.
     SmallVector<std::pair<const ToolChain *, StringRef>> TCAndArchs;
     for (const ToolChain *TC : ToolChains)
-      for (StringRef Arch : getOffloadArchs(
-               C, C.getArgsForToolChain(TC, "generic", Kind), Kind, TC))
+      for (StringRef Arch : getOffloadArchs(C, Args, Kind, TC))
         TCAndArchs.push_back(std::make_pair(TC, Arch));
 
     for (unsigned I = 0, E = TCAndArchs.size(); I != E; ++I)
@@ -4477,11 +4486,23 @@ Action *Driver::BuildOffloadingActions(Compilation &C,
   if (offloadDeviceOnly())
     return C.MakeAction<OffloadAction>(DDeps, types::TY_Nothing);
 
-  Action *OffloadPackager =
-      C.MakeAction<OffloadPackagerJobAction>(OffloadActions, types::TY_Image);
   OffloadAction::DeviceDependences DDep;
-  DDep.add(*OffloadPackager, *C.getSingleOffloadToolChain<Action::OFK_Host>(),
-           nullptr, Action::OFK_None);
+  if (C.isOffloadingHostKind(Action::OFK_Cuda) &&
+      !Args.hasFlag(options::OPT_fgpu_rdc, options::OPT_fno_gpu_rdc, false)) {
+    // If we are not in RDC-mode we just emit the final CUDA fatbinary for each
+    // translation unit without requiring any linking.
+    Action *FatbinAction =
+        C.MakeAction<LinkJobAction>(OffloadActions, types::TY_CUDA_FATBIN);
+    DDep.add(*FatbinAction, *C.getSingleOffloadToolChain<Action::OFK_Cuda>(),
+             nullptr, Action::OFK_Cuda);
+  } else {
+    // Package all the offloading actions into a single output that can be
+    // embedded in the host and linked.
+    Action *PackagerAction =
+        C.MakeAction<OffloadPackagerJobAction>(OffloadActions, types::TY_Image);
+    DDep.add(*PackagerAction, *C.getSingleOffloadToolChain<Action::OFK_Host>(),
+             nullptr, Action::OFK_None);
+  }
   OffloadAction::HostDependence HDep(
       *HostAction, *C.getSingleOffloadToolChain<Action::OFK_Host>(),
       /*BoundArch=*/nullptr, isa<CompileJobAction>(HostAction) ? DDep : DDeps);
diff --git a/clang/lib/Driver/ToolChains/AVR.cpp b/clang/lib/Driver/ToolChains/AVR.cpp
index 1e866553d826..89d408823270 100644
--- a/clang/lib/Driver/ToolChains/AVR.cpp
+++ b/clang/lib/Driver/ToolChains/AVR.cpp
@@ -437,7 +437,6 @@ void AVR::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                          : getToolChain().GetProgramPath(getShortName());
 
   ArgStringList CmdArgs;
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
@@ -476,8 +475,8 @@ void AVR::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   if (SectionAddressData) {
-    std::string DataSectionArg = std::string("-Tdata=0x") +
-                                 llvm::utohexstr(SectionAddressData.getValue());
+    std::string DataSectionArg =
+        std::string("-Tdata=0x") + llvm::utohexstr(SectionAddressData.value());
     CmdArgs.push_back(Args.MakeArgString(DataSectionArg));
   } else {
     // We do not have an entry for this CPU in the address mapping table yet.
@@ -503,6 +502,7 @@ void AVR::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     // Add the link library specific to the MCU.
     CmdArgs.push_back(Args.MakeArgString(std::string("-l") + CPU));
 
+    AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
     CmdArgs.push_back("--end-group");
 
     // Add user specified linker script.
@@ -514,6 +514,8 @@ void AVR::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     // than the bare minimum supports.
     if (Linker.find("avr-ld") != std::string::npos)
       CmdArgs.push_back(Args.MakeArgString(std::string("-m") + *FamilyName));
+  } else {
+    AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
   }
 
   C.addCommand(std::make_unique<Command>(
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index c9bbdb2ac72e..97435f1a73de 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -27,6 +27,7 @@
 #include "clang/Basic/CharInfo.h"
 #include "clang/Basic/CodeGenOptions.h"
 #include "clang/Basic/LangOptions.h"
+#include "clang/Basic/MakeSupport.h"
 #include "clang/Basic/ObjCRuntime.h"
 #include "clang/Basic/Version.h"
 #include "clang/Config/config.h"
@@ -51,6 +52,7 @@
 #include "llvm/Support/Process.h"
 #include "llvm/Support/TargetParser.h"
 #include "llvm/Support/YAMLParser.h"
+#include <cctype>
 
 using namespace clang::driver;
 using namespace clang::driver::tools;
@@ -97,34 +99,6 @@ static void EscapeSpacesAndBackslashes(const char *Arg,
   }
 }
 
-// Quote target names for inclusion in GNU Make dependency files.
-// Only the characters '$', '#', ' ', '\t' are quoted.
-static void QuoteTarget(StringRef Target, SmallVectorImpl<char> &Res) {
-  for (unsigned i = 0, e = Target.size(); i != e; ++i) {
-    switch (Target[i]) {
-    case ' ':
-    case '\t':
-      // Escape the preceding backslashes
-      for (int j = i - 1; j >= 0 && Target[j] == '\\'; --j)
-        Res.push_back('\\');
-
-      // Escape the space/tab
-      Res.push_back('\\');
-      break;
-    case '$':
-      Res.push_back('$');
-      break;
-    case '#':
-      Res.push_back('\\');
-      break;
-    default:
-      break;
-    }
-
-    Res.push_back(Target[i]);
-  }
-}
-
 /// Apply \a Work on the current tool chain \a RegularToolChain and any other
 /// offloading tool chain that is associated with the current action \a JA.
 static void
@@ -567,7 +541,7 @@ static bool useFramePointerForTargetByDefault(const ArgList &Args,
     break;
   }
 
-  if (Triple.isOSNetBSD()) {
+  if (Triple.isOSFuchsia() || Triple.isOSNetBSD()) {
     return !areOptimizationsEnabled(Args);
   }
 
@@ -1144,7 +1118,7 @@ static void RenderDebugInfoCompressionArgs(const ArgList &Args,
     if (Value == "none") {
       CmdArgs.push_back("--compress-debug-sections=none");
     } else if (Value == "zlib") {
-      if (llvm::zlib::isAvailable()) {
+      if (llvm::compression::zlib::isAvailable()) {
         CmdArgs.push_back(
             Args.MakeArgString("--compress-debug-sections=" + Twine(Value)));
       } else {
@@ -1249,7 +1223,7 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
       } else {
         CmdArgs.push_back("-MT");
         SmallString<128> Quoted;
-        QuoteTarget(A->getValue(), Quoted);
+        quoteMakeTarget(A->getValue(), Quoted);
         CmdArgs.push_back(Args.MakeArgString(Quoted));
       }
     }
@@ -1274,7 +1248,7 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
 
       CmdArgs.push_back("-MT");
       SmallString<128> Quoted;
-      QuoteTarget(DepTarget, Quoted);
+      quoteMakeTarget(DepTarget, Quoted);
       CmdArgs.push_back(Args.MakeArgString(Quoted));
     }
 
@@ -2228,8 +2202,23 @@ void Clang::AddSparcTargetArgs(const ArgList &Args,
 
 void Clang::AddSystemZTargetArgs(const ArgList &Args,
                                  ArgStringList &CmdArgs) const {
-  bool HasBackchain = Args.hasFlag(options::OPT_mbackchain,
-                                   options::OPT_mno_backchain, false);
+  if (const Arg *A = Args.getLastArg(clang::driver::options::OPT_mtune_EQ)) {
+    StringRef Name = A->getValue();
+
+    std::string TuneCPU;
+    if (Name == "native")
+      TuneCPU = std::string(llvm::sys::getHostCPUName());
+    else
+      TuneCPU = std::string(Name);
+
+    if (!TuneCPU.empty()) {
+      CmdArgs.push_back("-tune-cpu");
+      CmdArgs.push_back(Args.MakeArgString(TuneCPU));
+    }
+  }
+
+  bool HasBackchain =
+      Args.hasFlag(options::OPT_mbackchain, options::OPT_mno_backchain, false);
   bool HasPackedStack = Args.hasFlag(options::OPT_mpacked_stack,
                                      options::OPT_mno_packed_stack, false);
   systemz::FloatABI FloatABI =
@@ -2341,7 +2330,7 @@ void Clang::AddHexagonTargetArgs(const ArgList &Args,
   if (auto G = toolchains::HexagonToolChain::getSmallDataThreshold(Args)) {
     CmdArgs.push_back("-mllvm");
     CmdArgs.push_back(Args.MakeArgString("-hexagon-small-data-threshold=" +
-                                         Twine(G.getValue())));
+                                         Twine(G.value())));
   }
 
   if (!Args.hasArg(options::OPT_fno_short_enums))
@@ -3231,6 +3220,16 @@ static void RenderAnalyzerOptions(const ArgList &Args, ArgStringList &CmdArgs,
   Args.AddAllArgValues(CmdArgs, options::OPT_Xanalyzer);
 }
 
+static bool isValidSymbolName(StringRef S) {
+  if (S.empty())
+    return false;
+
+  if (std::isdigit(S[0]))
+    return false;
+
+  return llvm::all_of(S, [](char C) { return std::isalnum(C) || C == '_'; });
+}
+
 static void RenderSSPOptions(const Driver &D, const ToolChain &TC,
                              const ArgList &Args, ArgStringList &CmdArgs,
                              bool KernelOrKext) {
@@ -3362,6 +3361,16 @@ static void RenderSSPOptions(const Driver &D, const ToolChain &TC,
     }
     A->render(Args, CmdArgs);
   }
+
+  if (Arg *A = Args.getLastArg(options::OPT_mstack_protector_guard_symbol_EQ)) {
+    StringRef Value = A->getValue();
+    if (!isValidSymbolName(Value)) {
+      D.Diag(diag::err_drv_argument_only_allowed_with)
+          << A->getOption().getName() << "legal symbol name";
+      return;
+    }
+    A->render(Args, CmdArgs);
+  }
 }
 
 static void RenderSCPOptions(const ToolChain &TC, const ArgList &Args,
@@ -3750,38 +3759,49 @@ static void RenderModulesOptions(Compilation &C, const Driver &D,
   Args.AddLastArg(CmdArgs, options::OPT_fmodules_prune_interval);
   Args.AddLastArg(CmdArgs, options::OPT_fmodules_prune_after);
 
-  Args.AddLastArg(CmdArgs, options::OPT_fbuild_session_timestamp);
+  if (HaveClangModules) {
+    Args.AddLastArg(CmdArgs, options::OPT_fbuild_session_timestamp);
 
-  if (Arg *A = Args.getLastArg(options::OPT_fbuild_session_file)) {
-    if (Args.hasArg(options::OPT_fbuild_session_timestamp))
-      D.Diag(diag::err_drv_argument_not_allowed_with)
-          << A->getAsString(Args) << "-fbuild-session-timestamp";
+    if (Arg *A = Args.getLastArg(options::OPT_fbuild_session_file)) {
+      if (Args.hasArg(options::OPT_fbuild_session_timestamp))
+        D.Diag(diag::err_drv_argument_not_allowed_with)
+            << A->getAsString(Args) << "-fbuild-session-timestamp";
 
-    llvm::sys::fs::file_status Status;
-    if (llvm::sys::fs::status(A->getValue(), Status))
-      D.Diag(diag::err_drv_no_such_file) << A->getValue();
-    CmdArgs.push_back(Args.MakeArgString(
-        "-fbuild-session-timestamp=" +
-        Twine((uint64_t)std::chrono::duration_cast<std::chrono::seconds>(
-                  Status.getLastModificationTime().time_since_epoch())
-                  .count())));
-  }
+      llvm::sys::fs::file_status Status;
+      if (llvm::sys::fs::status(A->getValue(), Status))
+        D.Diag(diag::err_drv_no_such_file) << A->getValue();
+      CmdArgs.push_back(Args.MakeArgString(
+          "-fbuild-session-timestamp=" +
+          Twine((uint64_t)std::chrono::duration_cast<std::chrono::seconds>(
+                    Status.getLastModificationTime().time_since_epoch())
+                    .count())));
+    }
 
-  if (Args.getLastArg(options::OPT_fmodules_validate_once_per_build_session)) {
-    if (!Args.getLastArg(options::OPT_fbuild_session_timestamp,
-                         options::OPT_fbuild_session_file))
-      D.Diag(diag::err_drv_modules_validate_once_requires_timestamp);
+    if (Args.getLastArg(
+            options::OPT_fmodules_validate_once_per_build_session)) {
+      if (!Args.getLastArg(options::OPT_fbuild_session_timestamp,
+                           options::OPT_fbuild_session_file))
+        D.Diag(diag::err_drv_modules_validate_once_requires_timestamp);
 
-    Args.AddLastArg(CmdArgs,
-                    options::OPT_fmodules_validate_once_per_build_session);
-  }
+      Args.AddLastArg(CmdArgs,
+                      options::OPT_fmodules_validate_once_per_build_session);
+    }
 
-  if (Args.hasFlag(options::OPT_fmodules_validate_system_headers,
-                   options::OPT_fno_modules_validate_system_headers,
-                   ImplicitModules))
-    CmdArgs.push_back("-fmodules-validate-system-headers");
+    if (Args.hasFlag(options::OPT_fmodules_validate_system_headers,
+                     options::OPT_fno_modules_validate_system_headers,
+                     ImplicitModules))
+      CmdArgs.push_back("-fmodules-validate-system-headers");
 
-  Args.AddLastArg(CmdArgs, options::OPT_fmodules_disable_diagnostic_validation);
+    Args.AddLastArg(CmdArgs,
+                    options::OPT_fmodules_disable_diagnostic_validation);
+  } else {
+    Args.ClaimAllArgs(options::OPT_fbuild_session_timestamp);
+    Args.ClaimAllArgs(options::OPT_fbuild_session_file);
+    Args.ClaimAllArgs(options::OPT_fmodules_validate_once_per_build_session);
+    Args.ClaimAllArgs(options::OPT_fmodules_validate_system_headers);
+    Args.ClaimAllArgs(options::OPT_fno_modules_validate_system_headers);
+    Args.ClaimAllArgs(options::OPT_fmodules_disable_diagnostic_validation);
+  }
 }
 
 static void RenderCharacterOptions(const ArgList &Args, const llvm::Triple &T,
@@ -4422,12 +4442,14 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
        Args.hasFlag(options::OPT_offload_new_driver,
                     options::OPT_no_offload_new_driver, false));
 
+  bool IsRDCMode =
+      Args.hasFlag(options::OPT_fgpu_rdc, options::OPT_fno_gpu_rdc, false);
   bool IsUsingLTO = D.isUsingLTO(IsDeviceOffloadAction);
   auto LTOMode = D.getLTOMode(IsDeviceOffloadAction);
 
   // A header module compilation doesn't have a main input file, so invent a
   // fake one as a placeholder.
-  const char *ModuleName = [&]{
+  const char *ModuleName = [&] {
     auto *ModuleNameArg = Args.getLastArg(options::OPT_fmodule_name_EQ);
     return ModuleNameArg ? ModuleNameArg->getValue() : "";
   }();
@@ -6285,10 +6307,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   if (IsCuda || IsHIP) {
-    if (!Args.hasFlag(options::OPT_fgpu_rdc, options::OPT_fno_gpu_rdc, false) &&
-        Args.hasArg(options::OPT_offload_new_driver))
-      D.Diag(diag::err_drv_no_rdc_new_driver);
-    if (Args.hasFlag(options::OPT_fgpu_rdc, options::OPT_fno_gpu_rdc, false))
+    if (IsRDCMode)
       CmdArgs.push_back("-fgpu-rdc");
     if (Args.hasFlag(options::OPT_fgpu_defer_diag,
                      options::OPT_fno_gpu_defer_diag, false))
@@ -6313,6 +6332,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   if (IsUsingLTO)
     Args.AddLastArg(CmdArgs, options::OPT_mibt_seal);
 
+  if (Arg *A = Args.getLastArg(options::OPT_mfunction_return_EQ))
+    CmdArgs.push_back(
+        Args.MakeArgString(Twine("-mfunction-return=") + A->getValue()));
+
   // Forward -f options with positive and negative forms; we translate these by
   // hand.  Do not propagate PGO options to the GPU-side compilations as the
   // profile info is for the host-side compilation only.
@@ -6956,13 +6979,22 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     }
   }
 
-  // Host-side cuda compilation receives all device-side outputs in a single
-  // fatbin as Inputs[1]. Include the binary with -fcuda-include-gpubinary.
+  // Host-side offloading compilation receives all device-side outputs. Include
+  // them in the host compilation depending on the target. If the host inputs
+  // are not empty we use the new-driver scheme, otherwise use the old scheme.
   if ((IsCuda || IsHIP) && CudaDeviceInput) {
+    CmdArgs.push_back("-fcuda-include-gpubinary");
+    CmdArgs.push_back(CudaDeviceInput->getFilename());
+  } else if (!HostOffloadingInputs.empty()) {
+    if (IsCuda && !IsRDCMode) {
+      assert(HostOffloadingInputs.size() == 1 && "Only one input expected");
       CmdArgs.push_back("-fcuda-include-gpubinary");
-      CmdArgs.push_back(CudaDeviceInput->getFilename());
-      if (Args.hasFlag(options::OPT_fgpu_rdc, options::OPT_fno_gpu_rdc, false))
-        CmdArgs.push_back("-fgpu-rdc");
+      CmdArgs.push_back(HostOffloadingInputs.front().getFilename());
+    } else {
+      for (const InputInfo Input : HostOffloadingInputs)
+        CmdArgs.push_back(Args.MakeArgString("-fembed-offload-object=" +
+                                             TC.getInputFilename(Input)));
+    }
   }
 
   if (IsCuda) {
@@ -7011,12 +7043,6 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     }
   }
 
-  // Host-side offloading recieves the device object files and embeds it in a
-  // named section including the associated target triple and architecture.
-  for (const InputInfo Input : HostOffloadingInputs)
-    CmdArgs.push_back(Args.MakeArgString("-fembed-offload-object=" +
-                                         TC.getInputFilename(Input)));
-
   if (Triple.isAMDGPU()) {
     handleAMDGPUCodeObjectVersionOptions(D, Args, CmdArgs);
 
@@ -8314,7 +8340,8 @@ void OffloadPackager::ConstructJob(Compilation &C, const JobAction &JA,
 
     ArgStringList Features;
     SmallVector<StringRef> FeatureArgs;
-    getTargetFeatures(TC->getDriver(), TC->getTriple(), Args, Features, false);
+    getTargetFeatures(TC->getDriver(), TC->getTriple(), TCArgs, Features,
+                      false);
     llvm::copy_if(Features, std::back_inserter(FeatureArgs),
                   [](StringRef Arg) { return !Arg.startswith("-target"); });
 
@@ -8382,7 +8409,7 @@ void LinkerWrapper::ConstructJob(Compilation &C, const JobAction &JA,
 
     for (StringRef LibName : BCLibs)
       CmdArgs.push_back(Args.MakeArgString(
-          "-target-library=" + Action::GetOffloadKindName(Action::OFK_OpenMP) +
+          "--bitcode-library=" + Action::GetOffloadKindName(Action::OFK_OpenMP) +
           "-" + TC->getTripleString() + "-" + Arch + "=" + LibName));
   }
 
@@ -8402,63 +8429,64 @@ void LinkerWrapper::ConstructJob(Compilation &C, const JobAction &JA,
       } else if (A->getOption().matches(options::OPT_O0))
         OOpt = "0";
       if (!OOpt.empty())
-        CmdArgs.push_back(Args.MakeArgString(Twine("-opt-level=O") + OOpt));
+        CmdArgs.push_back(Args.MakeArgString(Twine("--opt-level=O") + OOpt));
     }
   }
 
-  CmdArgs.push_back("-host-triple");
-  CmdArgs.push_back(Args.MakeArgString(TheTriple.getTriple()));
+  CmdArgs.push_back(
+      Args.MakeArgString("--host-triple=" + TheTriple.getTriple()));
   if (Args.hasArg(options::OPT_v))
-    CmdArgs.push_back("-v");
+    CmdArgs.push_back("--verbose");
 
-  // Add debug information if present.
   if (const Arg *A = Args.getLastArg(options::OPT_g_Group)) {
-    const Option &Opt = A->getOption();
-    if (Opt.matches(options::OPT_gN_Group)) {
-      if (Opt.matches(options::OPT_gline_directives_only) ||
-          Opt.matches(options::OPT_gline_tables_only))
-        CmdArgs.push_back("-gline-directives-only");
-    } else
-      CmdArgs.push_back("-g");
+    if (!A->getOption().matches(options::OPT_g0))
+      CmdArgs.push_back("--device-debug");
   }
 
   for (const auto &A : Args.getAllArgValues(options::OPT_Xcuda_ptxas))
-    CmdArgs.push_back(Args.MakeArgString("-ptxas-args=" + A));
+    CmdArgs.push_back(Args.MakeArgString("--ptxas-args=" + A));
 
   // Forward remarks passes to the LLVM backend in the wrapper.
   if (const Arg *A = Args.getLastArg(options::OPT_Rpass_EQ))
     CmdArgs.push_back(
-        Args.MakeArgString(Twine("-pass-remarks=") + A->getValue()));
+        Args.MakeArgString(Twine("--pass-remarks=") + A->getValue()));
   if (const Arg *A = Args.getLastArg(options::OPT_Rpass_missed_EQ))
     CmdArgs.push_back(
-        Args.MakeArgString(Twine("-pass-remarks-missed=") + A->getValue()));
+        Args.MakeArgString(Twine("--pass-remarks-missed=") + A->getValue()));
   if (const Arg *A = Args.getLastArg(options::OPT_Rpass_analysis_EQ))
     CmdArgs.push_back(
-        Args.MakeArgString(Twine("-pass-remarks-analysis=") + A->getValue()));
+        Args.MakeArgString(Twine("--pass-remarks-analysis=") + A->getValue()));
   if (Args.getLastArg(options::OPT_save_temps_EQ))
-    CmdArgs.push_back("-save-temps");
+    CmdArgs.push_back("--save-temps");
 
   // Construct the link job so we can wrap around it.
   Linker->ConstructJob(C, JA, Output, Inputs, Args, LinkingOutput);
   const auto &LinkCommand = C.getJobs().getJobs().back();
 
   // Forward -Xoffload-linker<-triple> arguments to the device link job.
-  for (auto *Arg : Args.filtered(options::OPT_Xoffload_linker)) {
-    StringRef Val = Arg->getValue(0);
+  for (Arg *A : Args.filtered(options::OPT_Xoffload_linker)) {
+    StringRef Val = A->getValue(0);
     if (Val.empty())
       CmdArgs.push_back(
-          Args.MakeArgString(Twine("-device-linker=") + Arg->getValue(1)));
+          Args.MakeArgString(Twine("--device-linker=") + A->getValue(1)));
     else
       CmdArgs.push_back(Args.MakeArgString(
-          "-device-linker=" +
+          "--device-linker=" +
           ToolChain::getOpenMPTriple(Val.drop_front()).getTriple() + "=" +
-          Arg->getValue(1)));
+          A->getValue(1)));
   }
   Args.ClaimAllArgs(options::OPT_Xoffload_linker);
 
+  // Forward `-mllvm` arguments to the LLVM invocations if present.
+  for (Arg *A : Args.filtered(options::OPT_mllvm)) {
+    CmdArgs.push_back("-mllvm");
+    CmdArgs.push_back(A->getValue());
+    A->claim();
+  }
+
   // Add the linker arguments to be forwarded by the wrapper.
-  CmdArgs.push_back("-linker-path");
-  CmdArgs.push_back(LinkCommand->getExecutable());
+  CmdArgs.push_back(Args.MakeArgString(Twine("--linker-path=") +
+                                       LinkCommand->getExecutable()));
   CmdArgs.push_back("--");
   for (const char *LinkArg : LinkCommand->getArguments())
     CmdArgs.push_back(LinkArg);
diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index 2d53b829b01c..1d2c085d683e 100644
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -727,7 +727,8 @@ bool tools::addOpenMPRuntime(ArgStringList &CmdArgs, const ToolChain &TC,
   if (IsOffloadingHost)
     CmdArgs.push_back("-lomptarget");
 
-  if (IsOffloadingHost && TC.getDriver().isUsingLTO(/* IsOffload */ true))
+  if (IsOffloadingHost && TC.getDriver().isUsingLTO(/* IsOffload */ true) &&
+      !Args.hasArg(options::OPT_nogpulib))
     CmdArgs.push_back("-lomptarget.devicertl");
 
   addArchSpecificRPath(TC, Args, CmdArgs);
diff --git a/clang/lib/Driver/ToolChains/Darwin.cpp b/clang/lib/Driver/ToolChains/Darwin.cpp
index 0a8a9c6eb6ff..c9e773701ac3 100644
--- a/clang/lib/Driver/ToolChains/Darwin.cpp
+++ b/clang/lib/Driver/ToolChains/Darwin.cpp
@@ -1551,10 +1551,10 @@ struct DarwinPlatform {
     options::ID Opt;
     switch (Platform) {
     case DarwinPlatformKind::MacOS:
-      Opt = options::OPT_mmacosx_version_min_EQ;
+      Opt = options::OPT_mmacos_version_min_EQ;
       break;
     case DarwinPlatformKind::IPhoneOS:
-      Opt = options::OPT_miphoneos_version_min_EQ;
+      Opt = options::OPT_mios_version_min_EQ;
       break;
     case DarwinPlatformKind::TvOS:
       Opt = options::OPT_mtvos_version_min_EQ;
@@ -1727,8 +1727,8 @@ private:
 Optional<DarwinPlatform>
 getDeploymentTargetFromOSVersionArg(DerivedArgList &Args,
                                     const Driver &TheDriver) {
-  Arg *OSXVersion = Args.getLastArg(options::OPT_mmacosx_version_min_EQ);
-  Arg *iOSVersion = Args.getLastArg(options::OPT_miphoneos_version_min_EQ,
+  Arg *macOSVersion = Args.getLastArg(options::OPT_mmacos_version_min_EQ);
+  Arg *iOSVersion = Args.getLastArg(options::OPT_mios_version_min_EQ,
                                     options::OPT_mios_simulator_version_min_EQ);
   Arg *TvOSVersion =
       Args.getLastArg(options::OPT_mtvos_version_min_EQ,
@@ -1736,15 +1736,15 @@ getDeploymentTargetFromOSVersionArg(DerivedArgList &Args,
   Arg *WatchOSVersion =
       Args.getLastArg(options::OPT_mwatchos_version_min_EQ,
                       options::OPT_mwatchos_simulator_version_min_EQ);
-  if (OSXVersion) {
+  if (macOSVersion) {
     if (iOSVersion || TvOSVersion || WatchOSVersion) {
       TheDriver.Diag(diag::err_drv_argument_not_allowed_with)
-          << OSXVersion->getAsString(Args)
+          << macOSVersion->getAsString(Args)
           << (iOSVersion ? iOSVersion
                          : TvOSVersion ? TvOSVersion : WatchOSVersion)
                  ->getAsString(Args);
     }
-    return DarwinPlatform::createOSVersionArg(Darwin::MacOS, OSXVersion);
+    return DarwinPlatform::createOSVersionArg(Darwin::MacOS, macOSVersion);
   } else if (iOSVersion) {
     if (TvOSVersion || WatchOSVersion) {
       TheDriver.Diag(diag::err_drv_argument_not_allowed_with)
diff --git a/clang/lib/Driver/ToolChains/Gnu.cpp b/clang/lib/Driver/ToolChains/Gnu.cpp
index f52bb8af5ec9..34396b0b59c2 100644
--- a/clang/lib/Driver/ToolChains/Gnu.cpp
+++ b/clang/lib/Driver/ToolChains/Gnu.cpp
@@ -2087,7 +2087,7 @@ void Generic_GCC::GCCInstallationDetector::print(raw_ostream &OS) const {
 
 bool Generic_GCC::GCCInstallationDetector::getBiarchSibling(Multilib &M) const {
   if (BiarchSibling) {
-    M = BiarchSibling.getValue();
+    M = BiarchSibling.value();
     return true;
   }
   return false;
diff --git a/clang/lib/Driver/ToolChains/Hexagon.cpp b/clang/lib/Driver/ToolChains/Hexagon.cpp
index 9142dba81d54..ed07e710fc49 100644
--- a/clang/lib/Driver/ToolChains/Hexagon.cpp
+++ b/clang/lib/Driver/ToolChains/Hexagon.cpp
@@ -340,8 +340,8 @@ constructHexagonLinkArgs(Compilation &C, const JobAction &JA,
     CmdArgs.push_back("-pie");
 
   if (auto G = toolchains::HexagonToolChain::getSmallDataThreshold(Args)) {
-    CmdArgs.push_back(Args.MakeArgString("-G" + Twine(G.getValue())));
-    UseG0 = G.getValue() == 0;
+    CmdArgs.push_back(Args.MakeArgString("-G" + Twine(G.value())));
+    UseG0 = G.value() == 0;
   }
 
   CmdArgs.push_back("-o");
diff --git a/clang/lib/Driver/ToolChains/MinGW.cpp b/clang/lib/Driver/ToolChains/MinGW.cpp
index c4b4f8e9b89b..ae7c4c56bf9e 100644
--- a/clang/lib/Driver/ToolChains/MinGW.cpp
+++ b/clang/lib/Driver/ToolChains/MinGW.cpp
@@ -339,8 +339,9 @@ void tools::MinGW::Linker::ConstructJob(Compilation &C, const JobAction &JA,
 
 // Simplified from Generic_GCC::GCCInstallationDetector::ScanLibDirForGCCTriple.
 static bool findGccVersion(StringRef LibDir, std::string &GccLibDir,
-                           std::string &Ver) {
-  auto Version = toolchains::Generic_GCC::GCCVersion::Parse("0.0.0");
+                           std::string &Ver,
+                           toolchains::Generic_GCC::GCCVersion &Version) {
+  Version = toolchains::Generic_GCC::GCCVersion::Parse("0.0.0");
   std::error_code EC;
   for (llvm::sys::fs::directory_iterator LI(LibDir, EC), LE; !EC && LI != LE;
        LI = LI.increment(EC)) {
@@ -371,7 +372,7 @@ void toolchains::MinGW::findGccLibDir() {
     for (StringRef CandidateSysroot : SubdirNames) {
       llvm::SmallString<1024> LibDir(Base);
       llvm::sys::path::append(LibDir, CandidateLib, "gcc", CandidateSysroot);
-      if (findGccVersion(LibDir, GccLibDir, Ver)) {
+      if (findGccVersion(LibDir, GccLibDir, Ver, GccVer)) {
         SubdirName = std::string(CandidateSysroot);
         return;
       }
@@ -438,6 +439,11 @@ toolchains::MinGW::MinGW(const Driver &D, const llvm::Triple &Triple,
   getFilePaths().push_back(GccLibDir);
   getFilePaths().push_back(
       (Base + SubdirName + llvm::sys::path::get_separator() + "lib").str());
+
+  // Gentoo
+  getFilePaths().push_back(
+      (Base + SubdirName + llvm::sys::path::get_separator() + "mingw/lib").str());
+
   getFilePaths().push_back(Base + "lib");
   // openSUSE
   getFilePaths().push_back(Base + SubdirName + "/sys-root/mingw/lib");
@@ -593,6 +599,11 @@ void toolchains::MinGW::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
   addSystemInclude(DriverArgs, CC1Args,
                    Base + SubdirName + llvm::sys::path::get_separator() +
                        "include");
+
+  // Gentoo
+  addSystemInclude(DriverArgs, CC1Args,
+                   Base + SubdirName + llvm::sys::path::get_separator() + "usr/include");
+
   addSystemInclude(DriverArgs, CC1Args, Base + "include");
 }
 
@@ -620,7 +631,7 @@ void toolchains::MinGW::AddClangCXXStdlibIncludeArgs(
   }
 
   case ToolChain::CST_Libstdcxx:
-    llvm::SmallVector<llvm::SmallString<1024>, 4> CppIncludeBases;
+    llvm::SmallVector<llvm::SmallString<1024>, 7> CppIncludeBases;
     CppIncludeBases.emplace_back(Base);
     llvm::sys::path::append(CppIncludeBases[0], SubdirName, "include", "c++");
     CppIncludeBases.emplace_back(Base);
@@ -630,6 +641,15 @@ void toolchains::MinGW::AddClangCXXStdlibIncludeArgs(
     llvm::sys::path::append(CppIncludeBases[2], "include", "c++", Ver);
     CppIncludeBases.emplace_back(GccLibDir);
     llvm::sys::path::append(CppIncludeBases[3], "include", "c++");
+    CppIncludeBases.emplace_back(GccLibDir);
+    llvm::sys::path::append(CppIncludeBases[4], "include",
+                            "g++-v" + GccVer.Text);
+    CppIncludeBases.emplace_back(GccLibDir);
+    llvm::sys::path::append(CppIncludeBases[5], "include",
+                            "g++-v" + GccVer.MajorStr + "." + GccVer.MinorStr);
+    CppIncludeBases.emplace_back(GccLibDir);
+    llvm::sys::path::append(CppIncludeBases[6], "include",
+                            "g++-v" + GccVer.MajorStr);
     for (auto &CppIncludeBase : CppIncludeBases) {
       addSystemInclude(DriverArgs, CC1Args, CppIncludeBase);
       CppIncludeBase += Slash;
diff --git a/clang/lib/Driver/ToolChains/MinGW.h b/clang/lib/Driver/ToolChains/MinGW.h
index c9553b4f4652..f15f99dc8a8c 100644
--- a/clang/lib/Driver/ToolChains/MinGW.h
+++ b/clang/lib/Driver/ToolChains/MinGW.h
@@ -103,6 +103,7 @@ private:
 
   std::string Base;
   std::string GccLibDir;
+  clang::driver::toolchains::Generic_GCC::GCCVersion GccVer;
   std::string Ver;
   std::string SubdirName;
   mutable std::unique_ptr<tools::gcc::Preprocessor> Preprocessor;
diff --git a/clang/lib/Driver/ToolChains/RISCVToolchain.cpp b/clang/lib/Driver/ToolChains/RISCVToolchain.cpp
index a048765bc6d3..3491de22d371 100644
--- a/clang/lib/Driver/ToolChains/RISCVToolchain.cpp
+++ b/clang/lib/Driver/ToolChains/RISCVToolchain.cpp
@@ -201,8 +201,11 @@ void RISCV::Linker::ConstructJob(Compilation &C, const JobAction &JA,
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
-    if (ToolChain.ShouldLinkCXXStdlib(Args))
-      ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
+    if (D.CCCIsCXX()) {
+      if (ToolChain.ShouldLinkCXXStdlib(Args))
+        ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
+      CmdArgs.push_back("-lm");
+    }
     CmdArgs.push_back("--start-group");
     CmdArgs.push_back("-lc");
     CmdArgs.push_back("-lgloss");
diff --git a/clang/lib/ExtractAPI/Serialization/SymbolGraphSerializer.cpp b/clang/lib/ExtractAPI/Serialization/SymbolGraphSerializer.cpp
index c4797cea333f..709b781968bf 100644
--- a/clang/lib/ExtractAPI/Serialization/SymbolGraphSerializer.cpp
+++ b/clang/lib/ExtractAPI/Serialization/SymbolGraphSerializer.cpp
@@ -31,14 +31,14 @@ namespace {
 /// at position \p Key.
 void serializeObject(Object &Paren, StringRef Key, Optional<Object> Obj) {
   if (Obj)
-    Paren[Key] = std::move(Obj.getValue());
+    Paren[Key] = std::move(Obj.value());
 }
 
 /// Helper function to inject a JSON array \p Array into object \p Paren at
 /// position \p Key.
 void serializeArray(Object &Paren, StringRef Key, Optional<Array> Array) {
   if (Array)
-    Paren[Key] = std::move(Array.getValue());
+    Paren[Key] = std::move(Array.value());
 }
 
 /// Serialize a \c VersionTuple \p V with the Symbol Graph semantic version
diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
index 2cb985cdc4e5..1cd28ab073da 100644
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -37,7 +37,7 @@ static bool shouldIndentWrappedSelectorName(const FormatStyle &Style,
 // Returns the length of everything up to the first possible line break after
 // the ), ], } or > matching \c Tok.
 static unsigned getLengthToMatchingParen(const FormatToken &Tok,
-                                         const std::vector<ParenState> &Stack) {
+                                         const SmallVector<ParenState> &Stack) {
   // Normally whether or not a break before T is possible is calculated and
   // stored in T.CanBreakBefore. Braces, array initializers and text proto
   // messages like `key: < ... >` are an exception: a break is possible
@@ -404,6 +404,7 @@ bool ContinuationIndenter::mustBreak(const LineState &State) {
       (State.Column + State.Line->Last->TotalLength - Previous.TotalLength >
            getColumnLimit(State) ||
        CurrentState.BreakBeforeParameter) &&
+      (!Current.isTrailingComment() || Current.NewlinesBefore > 0) &&
       (Style.AllowShortFunctionsOnASingleLine != FormatStyle::SFS_All ||
        Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeColon ||
        Style.ColumnLimit != 0)) {
@@ -793,6 +794,7 @@ void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
               (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) {
     CurrentState.LastSpace = State.Column;
   } else if (Previous.is(TT_CtorInitializerColon) &&
+             (!Current.isTrailingComment() || Current.NewlinesBefore > 0) &&
              Style.BreakConstructorInitializers ==
                  FormatStyle::BCIS_AfterColon) {
     CurrentState.Indent = State.Column;
@@ -1032,7 +1034,7 @@ unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
     // be considered bin packing unless the relevant AllowAll option is false or
     // this is a dict/object literal.
     bool PreviousIsBreakingCtorInitializerColon =
-        Previous.is(TT_CtorInitializerColon) &&
+        PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
         Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon;
     if (!(Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
           PreviousIsBreakingCtorInitializerColon) ||
diff --git a/clang/lib/Format/ContinuationIndenter.h b/clang/lib/Format/ContinuationIndenter.h
index 494a9727d5ed..620060e68861 100644
--- a/clang/lib/Format/ContinuationIndenter.h
+++ b/clang/lib/Format/ContinuationIndenter.h
@@ -434,7 +434,7 @@ struct LineState {
 
   /// A stack keeping track of properties applying to parenthesis
   /// levels.
-  std::vector<ParenState> Stack;
+  SmallVector<ParenState> Stack;
 
   /// Ignore the stack of \c ParenStates for state comparison.
   ///
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 51526dc2a681..d13907faca43 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -2386,7 +2386,7 @@ private:
 
   tooling::Replacements generateFixes() {
     tooling::Replacements Fixes;
-    std::vector<FormatToken *> Tokens;
+    SmallVector<FormatToken *> Tokens;
     std::copy(DeletedTokens.begin(), DeletedTokens.end(),
               std::back_inserter(Tokens));
 
@@ -2580,7 +2580,7 @@ struct JavaImportDirective {
   StringRef Identifier;
   StringRef Text;
   unsigned Offset;
-  std::vector<StringRef> AssociatedCommentLines;
+  SmallVector<StringRef> AssociatedCommentLines;
   bool IsStatic;
 };
 
@@ -2983,7 +2983,7 @@ tooling::Replacements sortJavaImports(const FormatStyle &Style, StringRef Code,
   llvm::Regex ImportRegex(JavaImportRegexPattern);
   SmallVector<StringRef, 4> Matches;
   SmallVector<JavaImportDirective, 16> ImportsInBlock;
-  std::vector<StringRef> AssociatedCommentLines;
+  SmallVector<StringRef> AssociatedCommentLines;
 
   bool FormattingOff = false;
 
@@ -3433,17 +3433,19 @@ LangOptions getFormattingLangOpts(const FormatStyle &Style) {
 }
 
 const char *StyleOptionHelpDescription =
-    "Coding style, currently supports:\n"
-    "  LLVM, GNU, Google, Chromium, Microsoft, Mozilla, WebKit.\n"
-    "Use -style=file to load style configuration from\n"
-    ".clang-format file located in one of the parent\n"
-    "directories of the source file (or current\n"
-    "directory for stdin).\n"
-    "Use -style=file:<format_file_path> to explicitly specify\n"
-    "the configuration file.\n"
-    "Use -style=\"{key: value, ...}\" to set specific\n"
-    "parameters, e.g.:\n"
-    "  -style=\"{BasedOnStyle: llvm, IndentWidth: 8}\"";
+    "Set coding style. <string> can be:\n"
+    "1. A preset: LLVM, GNU, Google, Chromium, Microsoft,\n"
+    "   Mozilla, WebKit.\n"
+    "2. 'file' to load style configuration from a\n"
+    "   .clang-format file in one of the parent directories\n"
+    "   of the source file (for stdin, see --assume-filename).\n"
+    "   If no .clang-format file is found, falls back to\n"
+    "   --fallback-style.\n"
+    "   --style=file is the default.\n"
+    "3. 'file:<format_file_path>' to explicitly specify\n"
+    "   the configuration file.\n"
+    "4. \"{key: value, ...}\" to set specific parameters, e.g.:\n"
+    "   --style=\"{BasedOnStyle: llvm, IndentWidth: 8}\"";
 
 static FormatStyle::LanguageKind getLanguageByFileName(StringRef FileName) {
   if (FileName.endswith(".java"))
@@ -3498,6 +3500,7 @@ FormatStyle::LanguageKind guessLanguage(StringRef FileName, StringRef Code) {
   return GuessedLanguage;
 }
 
+// Update StyleOptionHelpDescription above when changing this.
 const char *DefaultFormatStyle = "file";
 
 const char *DefaultFallbackStyle = "LLVM";
diff --git a/clang/lib/Format/FormatToken.cpp b/clang/lib/Format/FormatToken.cpp
index 2c0fee6975c2..832af463206c 100644
--- a/clang/lib/Format/FormatToken.cpp
+++ b/clang/lib/Format/FormatToken.cpp
@@ -264,7 +264,7 @@ void CommaSeparatedList::precomputeFormattingInfos(const FormatToken *Token) {
   // We can never place more than ColumnLimit / 3 items in a row (because of the
   // spaces and the comma).
   unsigned MaxItems = Style.ColumnLimit / 3;
-  std::vector<unsigned> MinSizeInColumn;
+  SmallVector<unsigned> MinSizeInColumn;
   MinSizeInColumn.reserve(MaxItems);
   for (unsigned Columns = 1; Columns <= MaxItems; ++Columns) {
     ColumnFormat Format;
diff --git a/clang/lib/Format/FormatToken.h b/clang/lib/Format/FormatToken.h
index b6cc021affae..73e32979853f 100644
--- a/clang/lib/Format/FormatToken.h
+++ b/clang/lib/Format/FormatToken.h
@@ -497,6 +497,15 @@ public:
   // in a configured macro expansion.
   llvm::Optional<MacroExpansion> MacroCtx;
 
+  /// When macro expansion introduces nodes with children, those are marked as
+  /// \c MacroParent.
+  /// FIXME: The formatting code currently hard-codes the assumption that
+  /// child nodes are introduced by blocks following an opening brace.
+  /// This is deeply baked into the code and disentangling this will require
+  /// signficant refactorings. \c MacroParent allows us to special-case the
+  /// cases in which we treat parents as block-openers for now.
+  bool MacroParent = false;
+
   bool is(tok::TokenKind Kind) const { return Tok.is(Kind); }
   bool is(TokenType TT) const { return getType() == TT; }
   bool is(const IdentifierInfo *II) const {
diff --git a/clang/lib/Format/MacroCallReconstructor.cpp b/clang/lib/Format/MacroCallReconstructor.cpp
new file mode 100644
index 000000000000..ccff183cf0da
--- /dev/null
+++ b/clang/lib/Format/MacroCallReconstructor.cpp
@@ -0,0 +1,573 @@
+//===--- MacroCallReconstructor.cpp - Format C++ code -----------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file contains the implementation of MacroCallReconstructor, which fits
+/// an reconstructed macro call to a parsed set of UnwrappedLines.
+///
+//===----------------------------------------------------------------------===//
+
+#include "Macros.h"
+
+#include "UnwrappedLineParser.h"
+#include "clang/Basic/TokenKinds.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/Support/Debug.h"
+#include <cassert>
+
+#define DEBUG_TYPE "format-reconstruct"
+
+namespace clang {
+namespace format {
+
+// Call \p Call for each token in the unwrapped line given, passing
+// the token, its parent and whether it is the first token in the line.
+template <typename T>
+void forEachToken(const UnwrappedLine &Line, const T &Call,
+                  FormatToken *Parent = nullptr) {
+  bool First = true;
+  for (const auto &N : Line.Tokens) {
+    Call(N.Tok, Parent, First);
+    First = false;
+    for (const auto &Child : N.Children) {
+      forEachToken(Child, Call, N.Tok);
+    }
+  }
+}
+
+MacroCallReconstructor::MacroCallReconstructor(
+    unsigned Level,
+    const llvm::DenseMap<FormatToken *, std::unique_ptr<UnwrappedLine>>
+        &ActiveExpansions)
+    : Level(Level), IdToReconstructed(ActiveExpansions) {
+  Result.Tokens.push_back(std::make_unique<LineNode>());
+  ActiveReconstructedLines.push_back(&Result);
+}
+
+void MacroCallReconstructor::addLine(const UnwrappedLine &Line) {
+  assert(State != Finalized);
+  LLVM_DEBUG(llvm::dbgs() << "MCR: new line...\n");
+  forEachToken(Line, [&](FormatToken *Token, FormatToken *Parent, bool First) {
+    add(Token, Parent, First);
+  });
+  assert(InProgress || finished());
+}
+
+UnwrappedLine MacroCallReconstructor::takeResult() && {
+  finalize();
+  assert(Result.Tokens.size() == 1 && Result.Tokens.front()->Children.size() == 1);
+  UnwrappedLine Final =
+      createUnwrappedLine(*Result.Tokens.front()->Children.front(), Level);
+  assert(!Final.Tokens.empty());
+  return Final;
+}
+
+// Reconstruct the position of the next \p Token, given its parent \p
+// ExpandedParent in the incoming unwrapped line. \p First specifies whether it
+// is the first token in a given unwrapped line.
+void MacroCallReconstructor::add(FormatToken *Token,
+                                 FormatToken *ExpandedParent, bool First) {
+  LLVM_DEBUG(
+      llvm::dbgs() << "MCR: Token: " << Token->TokenText << ", Parent: "
+                   << (ExpandedParent ? ExpandedParent->TokenText : "<null>")
+                   << ", First: " << First << "\n");
+  // In order to be able to find the correct parent in the reconstructed token
+  // stream, we need to continue the last open reconstruction until we find the
+  // given token if it is part of the reconstructed token stream.
+  //
+  // Note that hidden tokens can be part of the reconstructed stream in nested
+  // macro calls.
+  // For example, given
+  //   #define C(x, y) x y
+  //   #define B(x) {x}
+  // And the call:
+  //   C(a, B(b))
+  // The outer macro call will be C(a, {b}), and the hidden token '}' can be
+  // found in the reconstructed token stream of that expansion level.
+  // In the expanded token stream
+  //   a {b}
+  // 'b' is a child of '{'. We need to continue the open expansion of the ','
+  // in the call of 'C' in order to correctly set the ',' as the parent of '{',
+  // so we later set the spelled token 'b' as a child of the ','.
+  if (!ActiveExpansions.empty() && Token->MacroCtx &&
+      (Token->MacroCtx->Role != MR_Hidden ||
+       ActiveExpansions.size() != Token->MacroCtx->ExpandedFrom.size())) {
+    if (/*PassedMacroComma = */ reconstructActiveCallUntil(Token))
+      First = true;
+  }
+
+  prepareParent(ExpandedParent, First);
+
+  if (Token->MacroCtx) {
+    // If this token was generated by a macro call, add the reconstructed
+    // equivalent of the token.
+    reconstruct(Token);
+  } else {
+    // Otherwise, we add it to the current line.
+    appendToken(Token);
+  }
+}
+
+// Adjusts the stack of active reconstructed lines so we're ready to push
+// tokens. The tokens to be pushed are children of ExpandedParent in the
+// expanded code.
+//
+// This may entail:
+// - creating a new line, if the parent is on the active line
+// - popping active lines, if the parent is further up the stack
+//
+// Postcondition:
+// ActiveReconstructedLines.back() is the line that has \p ExpandedParent or its
+// reconstructed replacement token as a parent (when possible) - that is, the
+// last token in \c ActiveReconstructedLines[ActiveReconstructedLines.size()-2]
+// is the parent of ActiveReconstructedLines.back() in the reconstructed
+// unwrapped line.
+void MacroCallReconstructor::prepareParent(FormatToken *ExpandedParent,
+                                           bool NewLine) {
+  LLVM_DEBUG({
+    llvm::dbgs() << "ParentMap:\n";
+    debugParentMap();
+  });
+  // We want to find the parent in the new unwrapped line, where the expanded
+  // parent might have been replaced during reconstruction.
+  FormatToken *Parent = getParentInResult(ExpandedParent);
+  LLVM_DEBUG(llvm::dbgs() << "MCR: New parent: "
+                          << (Parent ? Parent->TokenText : "<null>") << "\n");
+
+  FormatToken *OpenMacroParent = nullptr;
+  if (!MacroCallStructure.empty()) {
+    // Inside a macro expansion, it is possible to lose track of the correct
+    // parent - either because it is already popped, for example because it was
+    // in a different macro argument (e.g. M({, })), or when we work on invalid
+    // code.
+    // Thus, we use the innermost macro call's parent as the parent at which
+    // we stop; this allows us to stay within the macro expansion and keeps
+    // any problems confined to the extent of the macro call.
+    OpenMacroParent =
+        getParentInResult(MacroCallStructure.back().MacroCallLParen);
+    LLVM_DEBUG(llvm::dbgs()
+               << "MacroCallLParen: "
+               << MacroCallStructure.back().MacroCallLParen->TokenText
+               << ", OpenMacroParent: "
+               << (OpenMacroParent ? OpenMacroParent->TokenText : "<null>")
+               << "\n");
+  }
+  if (NewLine ||
+      (!ActiveReconstructedLines.back()->Tokens.empty() &&
+       Parent == ActiveReconstructedLines.back()->Tokens.back()->Tok)) {
+    // If we are at the first token in a new line, we want to also
+    // create a new line in the resulting reconstructed unwrapped line.
+    while (ActiveReconstructedLines.back()->Tokens.empty() ||
+           (Parent != ActiveReconstructedLines.back()->Tokens.back()->Tok &&
+            ActiveReconstructedLines.back()->Tokens.back()->Tok !=
+                OpenMacroParent)) {
+      ActiveReconstructedLines.pop_back();
+      assert(!ActiveReconstructedLines.empty());
+    }
+    assert(!ActiveReconstructedLines.empty());
+    ActiveReconstructedLines.back()->Tokens.back()->Children.push_back(
+        std::make_unique<ReconstructedLine>());
+    ActiveReconstructedLines.push_back(
+        &*ActiveReconstructedLines.back()->Tokens.back()->Children.back());
+  } else if (parentLine().Tokens.back()->Tok != Parent) {
+    // If we're not the first token in a new line, pop lines until we find
+    // the child of \c Parent in the stack.
+    while (Parent != parentLine().Tokens.back()->Tok &&
+           parentLine().Tokens.back()->Tok &&
+           parentLine().Tokens.back()->Tok != OpenMacroParent) {
+      ActiveReconstructedLines.pop_back();
+      assert(!ActiveReconstructedLines.empty());
+    }
+  }
+  assert(!ActiveReconstructedLines.empty());
+}
+
+// For a given \p Parent in the incoming expanded token stream, find the
+// corresponding parent in the output.
+FormatToken *MacroCallReconstructor::getParentInResult(FormatToken *Parent) {
+  FormatToken *Mapped = SpelledParentToReconstructedParent.lookup(Parent);
+  if (!Mapped)
+    return Parent;
+  for (; Mapped; Mapped = SpelledParentToReconstructedParent.lookup(Parent)) {
+    Parent = Mapped;
+  }
+  // If we use a different token than the parent in the expanded token stream
+  // as parent, mark it as a special parent, so the formatting code knows it
+  // needs to have its children formatted.
+  Parent->MacroParent = true;
+  return Parent;
+}
+
+// Reconstruct a \p Token that was expanded from a macro call.
+void MacroCallReconstructor::reconstruct(FormatToken *Token) {
+  assert(Token->MacroCtx);
+  // A single token can be the only result of a macro call:
+  // Given: #define ID(x, y) ;
+  // And the call: ID(<some>, <tokens>)
+  // ';' in the expanded stream will reconstruct all of ID(<some>, <tokens>).
+  if (Token->MacroCtx->StartOfExpansion) {
+    startReconstruction(Token);
+    // If the order of tokens in the expanded token stream is not the
+    // same as the order of tokens in the reconstructed stream, we need
+    // to reconstruct tokens that arrive later in the stream.
+    if (Token->MacroCtx->Role != MR_Hidden) {
+      reconstructActiveCallUntil(Token);
+    }
+  }
+  assert(!ActiveExpansions.empty());
+  if (ActiveExpansions.back().SpelledI != ActiveExpansions.back().SpelledE) {
+    assert(ActiveExpansions.size() == Token->MacroCtx->ExpandedFrom.size());
+    if (Token->MacroCtx->Role != MR_Hidden) {
+      // The current token in the reconstructed token stream must be the token
+      // we're looking for - we either arrive here after startReconstruction,
+      // which initiates the stream to the first token, or after
+      // continueReconstructionUntil skipped until the expected token in the
+      // reconstructed stream at the start of add(...).
+      assert(ActiveExpansions.back().SpelledI->Tok == Token);
+      processNextReconstructed();
+    } else if (!currentLine()->Tokens.empty()) {
+      // Map all hidden tokens to the last visible token in the output.
+      // If the hidden token is a parent, we'll use the last visible
+      // token as the parent of the hidden token's children.
+      SpelledParentToReconstructedParent[Token] =
+          currentLine()->Tokens.back()->Tok;
+    } else {
+      for (auto I = ActiveReconstructedLines.rbegin(),
+                E = ActiveReconstructedLines.rend();
+           I != E; ++I) {
+        if (!(*I)->Tokens.empty()) {
+          SpelledParentToReconstructedParent[Token] = (*I)->Tokens.back()->Tok;
+          break;
+        }
+      }
+    }
+  }
+  if (Token->MacroCtx->EndOfExpansion)
+    endReconstruction(Token);
+}
+
+// Given a \p Token that starts an expansion, reconstruct the beginning of the
+// macro call.
+// For example, given: #define ID(x) x
+// And the call: ID(int a)
+// Reconstructs: ID(
+void MacroCallReconstructor::startReconstruction(FormatToken *Token) {
+  assert(Token->MacroCtx);
+  assert(!Token->MacroCtx->ExpandedFrom.empty());
+  assert(ActiveExpansions.size() <= Token->MacroCtx->ExpandedFrom.size());
+#ifndef NDEBUG
+  // Check that the token's reconstruction stack matches our current
+  // reconstruction stack.
+  for (size_t I = 0; I < ActiveExpansions.size(); ++I) {
+    assert(ActiveExpansions[I].ID ==
+           Token->MacroCtx
+               ->ExpandedFrom[Token->MacroCtx->ExpandedFrom.size() - 1 - I]);
+  }
+#endif
+  // Start reconstruction for all calls for which this token is the first token
+  // generated by the call.
+  // Note that the token's expanded from stack is inside-to-outside, and the
+  // expansions for which this token is not the first are the outermost ones.
+  ArrayRef<FormatToken *> StartedMacros =
+      makeArrayRef(Token->MacroCtx->ExpandedFrom)
+          .drop_back(ActiveExpansions.size());
+  assert(StartedMacros.size() == Token->MacroCtx->StartOfExpansion);
+  // We reconstruct macro calls outside-to-inside.
+  for (FormatToken *ID : llvm::reverse(StartedMacros)) {
+    // We found a macro call to be reconstructed; the next time our
+    // reconstruction stack is empty we know we finished an reconstruction.
+#ifndef NDEBUG
+    State = InProgress;
+#endif
+    // Put the reconstructed macro call's token into our reconstruction stack.
+    auto IU = IdToReconstructed.find(ID);
+    assert(IU != IdToReconstructed.end());
+    ActiveExpansions.push_back(
+        {ID, IU->second->Tokens.begin(), IU->second->Tokens.end()});
+    // Process the macro call's identifier.
+    processNextReconstructed();
+    if (ActiveExpansions.back().SpelledI == ActiveExpansions.back().SpelledE)
+      continue;
+    if (ActiveExpansions.back().SpelledI->Tok->is(tok::l_paren)) {
+      // Process the optional opening parenthesis.
+      processNextReconstructed();
+    }
+  }
+}
+
+// Add all tokens in the reconstruction stream to the output until we find the
+// given \p Token.
+bool MacroCallReconstructor::reconstructActiveCallUntil(FormatToken *Token) {
+  assert(!ActiveExpansions.empty());
+  bool PassedMacroComma = false;
+  // FIXME: If Token was already expanded earlier, due to
+  // a change in order, we will not find it, but need to
+  // skip it.
+  while (ActiveExpansions.back().SpelledI != ActiveExpansions.back().SpelledE &&
+         ActiveExpansions.back().SpelledI->Tok != Token) {
+    PassedMacroComma = processNextReconstructed() || PassedMacroComma;
+  }
+  return PassedMacroComma;
+}
+
+// End all reconstructions for which \p Token is the final token.
+void MacroCallReconstructor::endReconstruction(FormatToken *Token) {
+  assert(Token->MacroCtx &&
+         (ActiveExpansions.size() >= Token->MacroCtx->EndOfExpansion));
+  for (size_t I = 0; I < Token->MacroCtx->EndOfExpansion; ++I) {
+#ifndef NDEBUG
+    // Check all remaining tokens but the final closing parenthesis and optional
+    // trailing comment were already reconstructed at an inner expansion level.
+    for (auto T = ActiveExpansions.back().SpelledI;
+         T != ActiveExpansions.back().SpelledE; ++T) {
+      FormatToken *Token = T->Tok;
+      bool ClosingParen = (std::next(T) == ActiveExpansions.back().SpelledE ||
+                           std::next(T)->Tok->isTrailingComment()) &&
+                          !Token->MacroCtx && Token->is(tok::r_paren);
+      bool TrailingComment = Token->isTrailingComment();
+      bool PreviousLevel =
+          Token->MacroCtx &&
+          (ActiveExpansions.size() < Token->MacroCtx->ExpandedFrom.size());
+      if (!ClosingParen && !TrailingComment && !PreviousLevel) {
+        llvm::dbgs() << "At token: " << Token->TokenText << "\n";
+      }
+      // In addition to the following cases, we can also run into this
+      // when a macro call had more arguments than expected; in that case,
+      // the comma and the remaining tokens in the macro call will potentially
+      // end up in the line when we finish the expansion.
+      // FIXME: Add the information which arguments are unused, and assert
+      // one of the cases below plus reconstructed macro argument tokens.
+      // assert(ClosingParen || TrailingComment || PreviousLevel);
+    }
+#endif
+    // Handle the remaining open tokens:
+    // - expand the closing parenthesis, if it exists, including an optional
+    //   trailing comment
+    // - handle tokens that were already reconstructed at an inner expansion
+    //   level
+    // - handle tokens when a macro call had more than the expected number of
+    //   arguments, i.e. when #define M(x) is called as M(a, b, c) we'll end
+    //   up with the sequence ", b, c)" being open at the end of the
+    //   reconstruction; we want to gracefully handle that case
+    //
+    // FIXME: See the above debug-check for what we will need to do to be
+    // able to assert this.
+    for (auto T = ActiveExpansions.back().SpelledI;
+         T != ActiveExpansions.back().SpelledE; ++T) {
+      processNextReconstructed();
+    }
+    ActiveExpansions.pop_back();
+  }
+}
+
+void MacroCallReconstructor::debugParentMap() const {
+  llvm::DenseSet<FormatToken *> Values;
+  for (const auto &P : SpelledParentToReconstructedParent)
+    Values.insert(P.second);
+
+  for (const auto &P : SpelledParentToReconstructedParent) {
+    if (Values.contains(P.first))
+      continue;
+    llvm::dbgs() << (P.first ? P.first->TokenText : "<null>");
+    for (auto I = SpelledParentToReconstructedParent.find(P.first),
+              E = SpelledParentToReconstructedParent.end();
+         I != E; I = SpelledParentToReconstructedParent.find(I->second)) {
+      llvm::dbgs() << " -> " << (I->second ? I->second->TokenText : "<null>");
+    }
+    llvm::dbgs() << "\n";
+  }
+}
+
+// If visible, add the next token of the reconstructed token sequence to the
+// output. Returns whether reconstruction passed a comma that is part of a
+// macro call.
+bool MacroCallReconstructor::processNextReconstructed() {
+  FormatToken *Token = ActiveExpansions.back().SpelledI->Tok;
+  ++ActiveExpansions.back().SpelledI;
+  if (Token->MacroCtx) {
+    // Skip tokens that are not part of the macro call.
+    if (Token->MacroCtx->Role == MR_Hidden) {
+      return false;
+    }
+    // Skip tokens we already expanded during an inner reconstruction.
+    // For example, given: #define ID(x) {x}
+    // And the call: ID(ID(f))
+    // We get two reconstructions:
+    // ID(f) -> {f}
+    // ID({f}) -> {{f}}
+    // We reconstruct f during the first reconstruction, and skip it during the
+    // second reconstruction.
+    if (ActiveExpansions.size() < Token->MacroCtx->ExpandedFrom.size()) {
+      return false;
+    }
+  }
+  // Tokens that do not have a macro context are tokens in that are part of the
+  // macro call that have not taken part in expansion.
+  if (!Token->MacroCtx) {
+    // Put the parentheses and commas of a macro call into the same line;
+    // if the arguments produce new unwrapped lines, they will become children
+    // of the corresponding opening parenthesis or comma tokens in the
+    // reconstructed call.
+    if (Token->is(tok::l_paren)) {
+      MacroCallStructure.push_back(MacroCallState(
+          currentLine(), parentLine().Tokens.back()->Tok, Token));
+      // All tokens that are children of the previous line's last token in the
+      // reconstructed token stream will now be children of the l_paren token.
+      // For example, for the line containing the macro calls:
+      //   auto x = ID({ID(2)});
+      // We will build up a map <null> -> ( -> ( with the first and second
+      // l_paren of the macro call respectively. New lines that come in with a
+      // <null> parent will then become children of the l_paren token of the
+      // currently innermost macro call.
+      SpelledParentToReconstructedParent[MacroCallStructure.back()
+                                             .ParentLastToken] = Token;
+      appendToken(Token);
+      prepareParent(Token, /*NewLine=*/true);
+      Token->MacroParent = true;
+      return false;
+    }
+    if (!MacroCallStructure.empty()) {
+      if (Token->is(tok::comma)) {
+        // Make new lines inside the next argument children of the comma token.
+        SpelledParentToReconstructedParent
+            [MacroCallStructure.back().Line->Tokens.back()->Tok] = Token;
+        Token->MacroParent = true;
+        appendToken(Token, MacroCallStructure.back().Line);
+        prepareParent(Token, /*NewLine=*/true);
+        return true;
+      }
+      if (Token->is(tok::r_paren)) {
+        appendToken(Token, MacroCallStructure.back().Line);
+        SpelledParentToReconstructedParent.erase(
+            MacroCallStructure.back().ParentLastToken);
+        MacroCallStructure.pop_back();
+        return false;
+      }
+    }
+  }
+  // Note that any tokens that are tagged with MR_None have been passed as
+  // arguments to the macro that have not been expanded, for example:
+  // Given: #define ID(X) x
+  // When calling: ID(a, b)
+  // 'b' will be part of the reconstructed token stream, but tagged MR_None.
+  // Given that erroring out in this case would be disruptive, we continue
+  // pushing the (unformatted) token.
+  // FIXME: This can lead to unfortunate formatting decisions - give the user
+  // a hint that their macro definition is broken.
+  appendToken(Token);
+  return false;
+}
+
+void MacroCallReconstructor::finalize() {
+#ifndef NDEBUG
+  assert(State != Finalized && finished());
+  State = Finalized;
+#endif
+
+  // We created corresponding unwrapped lines for each incoming line as children
+  // the the toplevel null token.
+  assert(Result.Tokens.size() == 1 && !Result.Tokens.front()->Children.empty());
+  LLVM_DEBUG({
+    llvm::dbgs() << "Finalizing reconstructed lines:\n";
+    debug(Result, 0);
+  });
+
+  // The first line becomes the top level line in the resulting unwrapped line.
+  LineNode &Top = *Result.Tokens.front();
+  auto *I = Top.Children.begin();
+  // Every subsequent line will become a child of the last token in the previous
+  // line, which is the token prior to the first token in the line.
+  LineNode *Last = (*I)->Tokens.back().get();
+  ++I;
+  for (auto *E = Top.Children.end(); I != E; ++I) {
+    assert(Last->Children.empty());
+    Last->Children.push_back(std::move(*I));
+
+    // Mark the previous line's last token as generated by a macro expansion
+    // so the formatting algorithm can take that into account.
+    Last->Tok->MacroParent = true;
+
+    Last = Last->Children.back()->Tokens.back().get();
+  }
+  Top.Children.resize(1);
+}
+
+void MacroCallReconstructor::appendToken(FormatToken *Token,
+                                         ReconstructedLine *L) {
+  L = L ? L : currentLine();
+  LLVM_DEBUG(llvm::dbgs() << "-> " << Token->TokenText << "\n");
+  L->Tokens.push_back(std::make_unique<LineNode>(Token));
+}
+
+UnwrappedLine
+MacroCallReconstructor::createUnwrappedLine(const ReconstructedLine &Line,
+                                            int Level) {
+  UnwrappedLine Result;
+  Result.Level = Level;
+  for (const auto &N : Line.Tokens) {
+    Result.Tokens.push_back(N->Tok);
+    UnwrappedLineNode &Current = Result.Tokens.back();
+    for (const auto &Child : N->Children) {
+      if (Child->Tokens.empty())
+        continue;
+      Current.Children.push_back(createUnwrappedLine(*Child, Level + 1));
+    }
+    if (Current.Children.size() == 1 &&
+        Current.Tok->isOneOf(tok::l_paren, tok::comma)) {
+      Result.Tokens.splice(Result.Tokens.end(),
+                           Current.Children.front().Tokens);
+      Current.Children.clear();
+    }
+  }
+  return Result;
+}
+
+void MacroCallReconstructor::debug(const ReconstructedLine &Line, int Level) {
+  for (int i = 0; i < Level; ++i)
+    llvm::dbgs() << " ";
+  for (const auto &N : Line.Tokens) {
+    if (!N)
+      continue;
+    if (N->Tok)
+      llvm::dbgs() << N->Tok->TokenText << " ";
+    for (const auto &Child : N->Children) {
+      llvm::dbgs() << "\n";
+      debug(*Child, Level + 1);
+      for (int i = 0; i < Level; ++i)
+        llvm::dbgs() << " ";
+    }
+  }
+  llvm::dbgs() << "\n";
+}
+
+MacroCallReconstructor::ReconstructedLine &
+MacroCallReconstructor::parentLine() {
+  return **std::prev(std::prev(ActiveReconstructedLines.end()));
+}
+
+MacroCallReconstructor::ReconstructedLine *
+MacroCallReconstructor::currentLine() {
+  return ActiveReconstructedLines.back();
+}
+
+MacroCallReconstructor::MacroCallState::MacroCallState(
+    MacroCallReconstructor::ReconstructedLine *Line,
+    FormatToken *ParentLastToken, FormatToken *MacroCallLParen)
+    : Line(Line), ParentLastToken(ParentLastToken),
+      MacroCallLParen(MacroCallLParen) {
+  LLVM_DEBUG(
+      llvm::dbgs() << "ParentLastToken: "
+                   << (ParentLastToken ? ParentLastToken->TokenText : "<null>")
+                   << "\n");
+
+  assert(MacroCallLParen->is(tok::l_paren));
+}
+
+} // namespace format
+} // namespace clang
diff --git a/clang/lib/Format/Macros.h b/clang/lib/Format/Macros.h
index da03beb09145..b26799c20f8c 100644
--- a/clang/lib/Format/Macros.h
+++ b/clang/lib/Format/Macros.h
@@ -1,4 +1,4 @@
-//===--- MacroExpander.h - Format C++ code ----------------------*- C++ -*-===//
+//===--- Macros.h - Format C++ code -----------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
@@ -22,40 +22,38 @@
 /// spelled token streams into expanded token streams when it encounters a
 /// macro call. The UnwrappedLineParser continues to parse UnwrappedLines
 /// from the expanded token stream.
-/// After the expanded unwrapped lines are parsed, the MacroUnexpander matches
-/// the spelled token stream into unwrapped lines that best resemble the
-/// structure of the expanded unwrapped lines.
+/// After the expanded unwrapped lines are parsed, the MacroCallReconstructor
+/// matches the spelled token stream into unwrapped lines that best resemble the
+/// structure of the expanded unwrapped lines. These reconstructed unwrapped
+/// lines are aliasing the tokens in the expanded token stream, so that token
+/// annotations will be reused when formatting the spelled macro calls.
 ///
-/// When formatting, clang-format formats the expanded unwrapped lines first,
-/// determining the token types. Next, it formats the spelled unwrapped lines,
-/// keeping the token types fixed, while allowing other formatting decisions
-/// to change.
+/// When formatting, clang-format annotates and formats the expanded unwrapped
+/// lines first, determining the token types. Next, it formats the spelled
+/// unwrapped lines, keeping the token types fixed, while allowing other
+/// formatting decisions to change.
 ///
 //===----------------------------------------------------------------------===//
 
 #ifndef CLANG_LIB_FORMAT_MACROS_H
 #define CLANG_LIB_FORMAT_MACROS_H
 
+#include <list>
+#include <map>
 #include <string>
-#include <unordered_map>
 #include <vector>
 
-#include "Encoding.h"
 #include "FormatToken.h"
 #include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 
-namespace llvm {
-class MemoryBuffer;
-} // namespace llvm
-
 namespace clang {
-class IdentifierTable;
-class SourceManager;
-
 namespace format {
-struct FormatStyle;
+
+struct UnwrappedLine;
+struct UnwrappedLineNode;
 
 /// Takes a set of macro definitions as strings and allows expanding calls to
 /// those macros.
@@ -130,10 +128,253 @@ private:
   const FormatStyle &Style;
   llvm::SpecificBumpPtrAllocator<FormatToken> &Allocator;
   IdentifierTable &IdentTable;
-  std::vector<std::unique_ptr<llvm::MemoryBuffer>> Buffers;
+  SmallVector<std::unique_ptr<llvm::MemoryBuffer>> Buffers;
   llvm::StringMap<Definition> Definitions;
 };
 
+/// Converts a sequence of UnwrappedLines containing expanded macros into a
+/// single UnwrappedLine containing the macro calls.  This UnwrappedLine may be
+/// broken into child lines, in a way that best conveys the structure of the
+/// expanded code.
+///
+/// In the simplest case, a spelled UnwrappedLine contains one macro, and after
+/// expanding it we have one expanded UnwrappedLine.  In general, macro
+/// expansions can span UnwrappedLines, and multiple macros can contribute
+/// tokens to the same line.  We keep consuming expanded lines until:
+/// *   all expansions that started have finished (we're not chopping any macros
+///     in half)
+/// *   *and* we've reached the end of a *spelled* unwrapped line.
+///
+/// A single UnwrappedLine represents this chunk of code.
+///
+/// After this point, the state of the spelled/expanded stream is "in sync"
+/// (both at the start of an UnwrappedLine, with no macros open), so the
+/// Unexpander can be thrown away and parsing can continue.
+///
+/// Given a mapping from the macro name identifier token in the macro call
+/// to the tokens of the macro call, for example:
+/// CLASSA -> CLASSA({public: void x();})
+///
+/// When getting the formatted lines of the expansion via the \c addLine method
+/// (each '->' specifies a call to \c addLine ):
+/// -> class A {
+/// -> public:
+/// ->   void x();
+/// -> };
+///
+/// Creates the tree of unwrapped lines containing the macro call tokens so that
+/// the macro call tokens fit the semantic structure of the expanded formatted
+/// lines:
+/// -> CLASSA({
+/// -> public:
+/// ->   void x();
+/// -> })
+class MacroCallReconstructor {
+public:
+  /// Create an Reconstructor whose resulting \p UnwrappedLine will start at
+  /// \p Level, using the map from name identifier token to the corresponding
+  /// tokens of the spelled macro call.
+  MacroCallReconstructor(
+      unsigned Level,
+      const llvm::DenseMap<FormatToken *, std::unique_ptr<UnwrappedLine>>
+          &ActiveExpansions);
+
+  /// For the given \p Line, match all occurences of tokens expanded from a
+  /// macro to unwrapped lines in the spelled macro call so that the resulting
+  /// tree of unwrapped lines best resembles the structure of unwrapped lines
+  /// passed in via \c addLine.
+  void addLine(const UnwrappedLine &Line);
+
+  /// Check whether at the current state there is no open macro expansion
+  /// that needs to be processed to finish an macro call.
+  /// Only when \c finished() is true, \c takeResult() can be called to retrieve
+  /// the resulting \c UnwrappedLine.
+  /// If there are multiple subsequent macro calls within an unwrapped line in
+  /// the spelled token stream, the calling code may also continue to call
+  /// \c addLine() when \c finished() is true.
+  bool finished() const { return ActiveExpansions.empty(); }
+
+  /// Retrieve the formatted \c UnwrappedLine containing the orginal
+  /// macro calls, formatted according to the expanded token stream received
+  /// via \c addLine().
+  /// Generally, this line tries to have the same structure as the expanded,
+  /// formatted unwrapped lines handed in via \c addLine(), with the exception
+  /// that for multiple top-level lines, each subsequent line will be the
+  /// child of the last token in its predecessor. This representation is chosen
+  /// because it is a precondition to the formatter that we get what looks like
+  /// a single statement in a single \c UnwrappedLine (i.e. matching parens).
+  ///
+  /// If a token in a macro argument is a child of a token in the expansion,
+  /// the parent will be the corresponding token in the macro call.
+  /// For example:
+  ///   #define C(a, b) class C { a b
+  ///   C(int x;, int y;)
+  /// would expand to
+  ///   class C { int x; int y;
+  /// where in a formatted line "int x;" and "int y;" would both be new separate
+  /// lines.
+  ///
+  /// In the result, "int x;" will be a child of the opening parenthesis in "C("
+  /// and "int y;" will be a child of the "," token:
+  ///   C (
+  ///     \- int x;
+  ///     ,
+  ///     \- int y;
+  ///     )
+  UnwrappedLine takeResult() &&;
+
+private:
+  void add(FormatToken *Token, FormatToken *ExpandedParent, bool First);
+  void prepareParent(FormatToken *ExpandedParent, bool First);
+  FormatToken *getParentInResult(FormatToken *Parent);
+  void reconstruct(FormatToken *Token);
+  void startReconstruction(FormatToken *Token);
+  bool reconstructActiveCallUntil(FormatToken *Token);
+  void endReconstruction(FormatToken *Token);
+  bool processNextReconstructed();
+  void finalize();
+
+  struct ReconstructedLine;
+
+  void appendToken(FormatToken *Token, ReconstructedLine *L = nullptr);
+  UnwrappedLine createUnwrappedLine(const ReconstructedLine &Line, int Level);
+  void debug(const ReconstructedLine &Line, int Level);
+  ReconstructedLine &parentLine();
+  ReconstructedLine *currentLine();
+  void debugParentMap() const;
+
+#ifndef NDEBUG
+  enum ReconstructorState {
+    Start,      // No macro expansion was found in the input yet.
+    InProgress, // During a macro reconstruction.
+    Finalized,  // Past macro reconstruction, the result is finalized.
+  };
+  ReconstructorState State = Start;
+#endif
+
+  // Node in which we build up the resulting unwrapped line; this type is
+  // analogous to UnwrappedLineNode.
+  struct LineNode {
+    LineNode() = default;
+    LineNode(FormatToken *Tok) : Tok(Tok) {}
+    FormatToken *Tok = nullptr;
+    llvm::SmallVector<std::unique_ptr<ReconstructedLine>> Children;
+  };
+
+  // Line in which we build up the resulting unwrapped line.
+  // FIXME: Investigate changing UnwrappedLine to a pointer type and using it
+  // instead of rolling our own type.
+  struct ReconstructedLine {
+    llvm::SmallVector<std::unique_ptr<LineNode>> Tokens;
+  };
+
+  // The line in which we collect the resulting reconstructed output.
+  // To reduce special cases in the algorithm, the first level of the line
+  // contains a single null token that has the reconstructed incoming
+  // lines as children.
+  // In the end, we stich the lines together so that each subsequent line
+  // is a child of the last token of the previous line. This is necessary
+  // in order to format the overall expression as a single logical line -
+  // if we created separate lines, we'd format them with their own top-level
+  // indent depending on the semantic structure, which is not desired.
+  ReconstructedLine Result;
+
+  // Stack of currently "open" lines, where each line's predecessor's last
+  // token is the parent token for that line.
+  llvm::SmallVector<ReconstructedLine *> ActiveReconstructedLines;
+
+  // Maps from the expanded token to the token that takes its place in the
+  // reconstructed token stream in terms of parent-child relationships.
+  // Note that it might take multiple steps to arrive at the correct
+  // parent in the output.
+  // Given: #define C(a, b) []() { a; b; }
+  // And a call: C(f(), g())
+  // The structure in the incoming formatted unwrapped line will be:
+  // []() {
+  //      |- f();
+  //      \- g();
+  // }
+  // with f and g being children of the opening brace.
+  // In the reconstructed call:
+  // C(f(), g())
+  //  \- f()
+  //      \- g()
+  // We want f to be a child of the opening parenthesis and g to be a child
+  // of the comma token in the macro call.
+  // Thus, we map
+  // { -> (
+  // and add
+  // ( -> ,
+  // once we're past the comma in the reconstruction.
+  llvm::DenseMap<FormatToken *, FormatToken *>
+      SpelledParentToReconstructedParent;
+
+  // Keeps track of a single expansion while we're reconstructing tokens it
+  // generated.
+  struct Expansion {
+    // The identifier token of the macro call.
+    FormatToken *ID;
+    // Our current position in the reconstruction.
+    std::list<UnwrappedLineNode>::iterator SpelledI;
+    // The end of the reconstructed token sequence.
+    std::list<UnwrappedLineNode>::iterator SpelledE;
+  };
+
+  // Stack of macro calls for which we're in the middle of an expansion.
+  llvm::SmallVector<Expansion> ActiveExpansions;
+
+  struct MacroCallState {
+    MacroCallState(ReconstructedLine *Line, FormatToken *ParentLastToken,
+                   FormatToken *MacroCallLParen);
+
+    ReconstructedLine *Line;
+
+    // The last token in the parent line or expansion, or nullptr if the macro
+    // expansion is on a top-level line.
+    //
+    // For example, in the macro call:
+    //   auto f = []() { ID(1); };
+    // The MacroCallState for ID will have '{' as ParentLastToken.
+    //
+    // In the macro call:
+    //   ID(ID(void f()));
+    // The MacroCallState of the outer ID will have nullptr as ParentLastToken,
+    // while the MacroCallState for the inner ID will have the '(' of the outer
+    // ID as ParentLastToken.
+    //
+    // In the macro call:
+    //   ID2(a, ID(b));
+    // The MacroCallState of ID will have ',' as ParentLastToken.
+    FormatToken *ParentLastToken;
+
+    // The l_paren of this MacroCallState's macro call.
+    FormatToken *MacroCallLParen;
+  };
+
+  // Keeps track of the lines into which the opening brace/parenthesis &
+  // argument separating commas for each level in the macro call go in order to
+  // put the corresponding closing brace/parenthesis into the same line in the
+  // output and keep track of which parents in the expanded token stream map to
+  // which tokens in the reconstructed stream.
+  // When an opening brace/parenthesis has children, we want the structure of
+  // the output line to be:
+  // |- MACRO
+  // |- (
+  // |  \- <argument>
+  // |- ,
+  // |  \- <argument>
+  // \- )
+  llvm::SmallVector<MacroCallState> MacroCallStructure;
+
+  // Level the generated UnwrappedLine will be at.
+  const unsigned Level;
+
+  // Maps from identifier of the macro call to an unwrapped line containing
+  // all tokens of the macro call.
+  const llvm::DenseMap<FormatToken *, std::unique_ptr<UnwrappedLine>>
+      &IdToReconstructed;
+};
+
 } // namespace format
 } // namespace clang
 
diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 029cb9097871..98c012994f45 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -4734,7 +4734,7 @@ bool TokenAnnotator::canBreakBefore(const AnnotatedLine &Line,
     // the first list element. Otherwise, it should be placed outside of the
     // list.
     return Left.is(BK_BracedInit) ||
-           (Left.is(TT_CtorInitializerColon) &&
+           (Left.is(TT_CtorInitializerColon) && Right.NewlinesBefore > 0 &&
             Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon);
   }
   if (Left.is(tok::question) && Right.is(tok::colon))
@@ -4894,8 +4894,10 @@ bool TokenAnnotator::canBreakBefore(const AnnotatedLine &Line,
   if (Right.is(tok::identifier) && Right.Next && Right.Next->is(TT_DictLiteral))
     return true;
 
-  if (Left.is(TT_CtorInitializerColon))
-    return Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon;
+  if (Left.is(TT_CtorInitializerColon)) {
+    return Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon &&
+           (!Right.isTrailingComment() || Right.NewlinesBefore > 0);
+  }
   if (Right.is(TT_CtorInitializerColon))
     return Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon;
   if (Left.is(TT_CtorInitializerComma) &&
diff --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp
index 22509a504246..abeb93d23776 100644
--- a/clang/lib/Format/UnwrappedLineFormatter.cpp
+++ b/clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -59,14 +59,12 @@ public:
     Offset = getIndentOffset(*Line.First);
     // Update the indent level cache size so that we can rely on it
     // having the right size in adjustToUnmodifiedline.
-    while (IndentForLevel.size() <= Line.Level)
-      IndentForLevel.push_back(-1);
+    skipLine(Line, /*UnknownIndent=*/true);
     if (Line.InPPDirective) {
       unsigned IndentWidth =
           (Style.PPIndentWidth >= 0) ? Style.PPIndentWidth : Style.IndentWidth;
       Indent = Line.Level * IndentWidth + AdditionalIndent;
     } else {
-      IndentForLevel.resize(Line.Level + 1);
       Indent = getIndent(Line.Level);
     }
     if (static_cast<int>(Indent) + Offset >= 0)
@@ -77,9 +75,9 @@ public:
 
   /// Update the indent state given that \p Line indent should be
   /// skipped.
-  void skipLine(const AnnotatedLine &Line) {
-    while (IndentForLevel.size() <= Line.Level)
-      IndentForLevel.push_back(Indent);
+  void skipLine(const AnnotatedLine &Line, bool UnknownIndent = false) {
+    if (Line.Level >= IndentForLevel.size())
+      IndentForLevel.resize(Line.Level + 1, UnknownIndent ? -1 : Indent);
   }
 
   /// Update the level indent to adapt to the given \p Line.
@@ -91,6 +89,7 @@ public:
     unsigned LevelIndent = Line.First->OriginalColumn;
     if (static_cast<int>(LevelIndent) - Offset >= 0)
       LevelIndent -= Offset;
+    assert(Line.Level < IndentForLevel.size());
     if ((!Line.First->is(tok::comment) || IndentForLevel[Line.Level] == -1) &&
         !Line.InPPDirective) {
       IndentForLevel[Line.Level] = LevelIndent;
@@ -159,7 +158,7 @@ private:
   const unsigned AdditionalIndent;
 
   /// The indent in characters for each level.
-  std::vector<int> IndentForLevel;
+  SmallVector<int> IndentForLevel;
 
   /// Offset of the current line relative to the indent level.
   ///
@@ -1133,7 +1132,7 @@ private:
   typedef std::pair<OrderedPenalty, StateNode *> QueueItem;
 
   /// The BFS queue type.
-  typedef std::priority_queue<QueueItem, std::vector<QueueItem>,
+  typedef std::priority_queue<QueueItem, SmallVector<QueueItem>,
                               std::greater<QueueItem>>
       QueueType;
 
diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index d3383292f7a3..97c3d86282a0 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -15,6 +15,7 @@
 #include "UnwrappedLineParser.h"
 #include "FormatToken.h"
 #include "TokenAnnotator.h"
+#include "clang/Basic/TokenKinds.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
@@ -1910,15 +1911,12 @@ void UnwrappedLineParser::parseStructuralElement(
         break;
 
       auto OneTokenSoFar = [&]() {
-        const UnwrappedLineNode *Tok = &Line->Tokens.front(),
-                                *End = Tok + Line->Tokens.size();
-        while (Tok != End && Tok->Tok->is(tok::comment))
-          ++Tok;
-        // In Verilog, macro invocations start with a backtick which the code
-        // treats as a hash.  Skip it.
-        if (Style.isVerilog() && Tok != End && Tok->Tok->is(tok::hash))
-          ++Tok;
-        return End - Tok == 1;
+        auto I = Line->Tokens.begin(), E = Line->Tokens.end();
+        while (I != E && I->Tok->is(tok::comment))
+          ++I;
+        while (I != E && Style.isVerilog() && I->Tok->is(tok::hash))
+          ++I;
+        return I != E && (++I == E);
       };
       if (OneTokenSoFar()) {
         if (FormatTok->is(tok::colon) && !Line->MustBeDeclaration) {
diff --git a/clang/lib/Format/UnwrappedLineParser.h b/clang/lib/Format/UnwrappedLineParser.h
index 8f63870412d0..3394bfab8b8e 100644
--- a/clang/lib/Format/UnwrappedLineParser.h
+++ b/clang/lib/Format/UnwrappedLineParser.h
@@ -20,6 +20,7 @@
 #include "clang/Format/Format.h"
 #include "llvm/ADT/BitVector.h"
 #include "llvm/Support/Regex.h"
+#include <list>
 #include <stack>
 #include <vector>
 
@@ -38,7 +39,7 @@ struct UnwrappedLine {
   UnwrappedLine();
 
   /// The \c Tokens comprising this \c UnwrappedLine.
-  std::vector<UnwrappedLineNode> Tokens;
+  std::list<UnwrappedLineNode> Tokens;
 
   /// The indent level of the \c UnwrappedLine.
   unsigned Level;
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index b982ca72c78c..2cd7efd862ec 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -115,9 +115,9 @@ bool CompilerInstance::createTarget() {
     auto TO = std::make_shared<TargetOptions>();
     TO->Triple = llvm::Triple::normalize(getFrontendOpts().AuxTriple);
     if (getFrontendOpts().AuxTargetCPU)
-      TO->CPU = getFrontendOpts().AuxTargetCPU.getValue();
+      TO->CPU = getFrontendOpts().AuxTargetCPU.value();
     if (getFrontendOpts().AuxTargetFeatures)
-      TO->FeaturesAsWritten = getFrontendOpts().AuxTargetFeatures.getValue();
+      TO->FeaturesAsWritten = getFrontendOpts().AuxTargetFeatures.value();
     TO->HostTriple = getTarget().getTriple().str();
     setAuxTarget(TargetInfo::CreateTargetInfo(getDiagnostics(), TO));
   }
@@ -757,6 +757,8 @@ void CompilerInstance::createSema(TranslationUnitKind TUKind,
 // Output Files
 
 void CompilerInstance::clearOutputFiles(bool EraseFiles) {
+  // The ASTConsumer can own streams that write to the output files.
+  assert(!hasASTConsumer() && "ASTConsumer should be reset");
   // Ignore errors that occur when trying to discard the temp file.
   for (OutputFile &OF : OutputFiles) {
     if (EraseFiles) {
@@ -1235,8 +1237,7 @@ compileModuleImpl(CompilerInstance &ImportingInstance, SourceLocation ImportLoc,
 
   // Execute the action to actually build the module in-place. Use a separate
   // thread so that we get a stack large enough.
-  llvm::CrashRecoveryContext CRC;
-  CRC.RunSafelyOnThread(
+  bool Crashed = !llvm::CrashRecoveryContext().RunSafelyOnThread(
       [&]() {
         GenerateModuleFromModuleMapAction Action;
         Instance.ExecuteAction(Action);
@@ -1249,9 +1250,15 @@ compileModuleImpl(CompilerInstance &ImportingInstance, SourceLocation ImportLoc,
                                             diag::remark_module_build_done)
     << ModuleName;
 
-  // Delete any remaining temporary files related to Instance, in case the
-  // module generation thread crashed.
-  Instance.clearOutputFiles(/*EraseFiles=*/true);
+  if (Crashed) {
+    // Clear the ASTConsumer if it hasn't been already, in case it owns streams
+    // that must be closed before clearing output files.
+    Instance.setSema(nullptr);
+    Instance.setASTConsumer(nullptr);
+
+    // Delete any remaining temporary files related to Instance.
+    Instance.clearOutputFiles(/*EraseFiles=*/true);
+  }
 
   // If \p AllowPCMWithCompilerErrors is set return 'success' even if errors
   // occurred.
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index abef4cf65496..48cd6a394107 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1485,6 +1485,9 @@ void CompilerInvocation::GenerateCodeGenArgs(
   if (Opts.IBTSeal)
     GenerateArg(Args, OPT_mibt_seal, SA);
 
+  if (Opts.FunctionReturnThunks)
+    GenerateArg(Args, OPT_mfunction_return_EQ, "thunk-extern", SA);
+
   for (const auto &F : Opts.LinkBitcodeFiles) {
     bool Builtint = F.LinkFlags == llvm::Linker::Flags::LinkOnlyNeeded &&
                     F.PropagateAttrs && F.Internalize;
@@ -1825,6 +1828,27 @@ bool CompilerInvocation::ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args,
       Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << Name;
   }
 
+  if (const Arg *A = Args.getLastArg(OPT_mfunction_return_EQ)) {
+    auto Val = llvm::StringSwitch<llvm::FunctionReturnThunksKind>(A->getValue())
+                   .Case("keep", llvm::FunctionReturnThunksKind::Keep)
+                   .Case("thunk-extern", llvm::FunctionReturnThunksKind::Extern)
+                   .Default(llvm::FunctionReturnThunksKind::Invalid);
+    // SystemZ might want to add support for "expolines."
+    if (!T.isX86())
+      Diags.Report(diag::err_drv_argument_not_allowed_with)
+          << A->getSpelling() << T.getTriple();
+    else if (Val == llvm::FunctionReturnThunksKind::Invalid)
+      Diags.Report(diag::err_drv_invalid_value)
+          << A->getAsString(Args) << A->getValue();
+    else if (Val == llvm::FunctionReturnThunksKind::Extern &&
+             Args.getLastArgValue(OPT_mcmodel_EQ).equals("large"))
+      Diags.Report(diag::err_drv_argument_not_allowed_with)
+          << A->getAsString(Args)
+          << Args.getLastArg(OPT_mcmodel_EQ)->getAsString(Args);
+    else
+      Opts.FunctionReturnThunks = static_cast<unsigned>(Val);
+  }
+
   if (Opts.PrepareForLTO && Args.hasArg(OPT_mibt_seal))
     Opts.IBTSeal = 1;
 
@@ -1952,7 +1976,7 @@ bool CompilerInvocation::ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args,
     } else {
       Opts.DiagnosticsHotnessThreshold = *ResultOrErr;
       if ((!Opts.DiagnosticsHotnessThreshold ||
-           Opts.DiagnosticsHotnessThreshold.getValue() > 0) &&
+           Opts.DiagnosticsHotnessThreshold.value() > 0) &&
           !UsingProfile)
         Diags.Report(diag::warn_drv_diagnostics_hotness_requires_pgo)
             << "-fdiagnostics-hotness-threshold=";
@@ -1969,7 +1993,7 @@ bool CompilerInvocation::ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args,
     } else {
       Opts.DiagnosticsMisExpectTolerance = *ResultOrErr;
       if ((!Opts.DiagnosticsMisExpectTolerance ||
-           Opts.DiagnosticsMisExpectTolerance.getValue() > 0) &&
+           Opts.DiagnosticsMisExpectTolerance.value() > 0) &&
           !UsingProfile)
         Diags.Report(diag::warn_drv_diagnostics_misexpect_requires_pgo)
             << "-fdiagnostics-misexpect-tolerance=";
diff --git a/clang/lib/Frontend/FrontendAction.cpp b/clang/lib/Frontend/FrontendAction.cpp
index 65160dd7e0b1..ed3e314cc73b 100644
--- a/clang/lib/Frontend/FrontendAction.cpp
+++ b/clang/lib/Frontend/FrontendAction.cpp
@@ -24,6 +24,7 @@
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/PreprocessorOptions.h"
 #include "clang/Parse/ParseAST.h"
+#include "clang/Sema/HLSLExternalSemaSource.h"
 #include "clang/Serialization/ASTDeserializationListener.h"
 #include "clang/Serialization/ASTReader.h"
 #include "clang/Serialization/GlobalModuleIndex.h"
@@ -580,6 +581,7 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
   auto FailureCleanup = llvm::make_scope_exit([&]() {
     if (HasBegunSourceFile)
       CI.getDiagnosticClient().EndSourceFile();
+    CI.setASTConsumer(nullptr);
     CI.clearOutputFiles(/*EraseFiles=*/true);
     CI.getLangOpts().setCompilingModule(LangOptions::CMK_None);
     setCurrentInput(FrontendInputFile());
@@ -1014,6 +1016,13 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
     CI.getASTContext().setExternalSource(Override);
   }
 
+  // Setup HLSL External Sema Source
+  if (CI.getLangOpts().HLSL && CI.hasASTContext()) {
+    IntrusiveRefCntPtr<ExternalASTSource> HLSLSema(
+        new HLSLExternalSemaSource());
+    CI.getASTContext().setExternalSource(HLSLSema);
+  }
+
   FailureCleanup.release();
   return true;
 }
diff --git a/clang/lib/Frontend/FrontendActions.cpp b/clang/lib/Frontend/FrontendActions.cpp
index f61c83a2a465..f833541caa25 100644
--- a/clang/lib/Frontend/FrontendActions.cpp
+++ b/clang/lib/Frontend/FrontendActions.cpp
@@ -854,8 +854,9 @@ void DumpModuleInfoAction::ExecuteAction() {
     std::error_code EC;
     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str(), EC,
                                            llvm::sys::fs::OF_TextWithCRLF));
+    OutputStream = OutFile.get();
   }
-  llvm::raw_ostream &Out = OutFile.get()? *OutFile.get() : llvm::outs();
+  llvm::raw_ostream &Out = OutputStream ? *OutputStream : llvm::outs();
 
   Out << "Information for module file '" << getCurrentFile() << "':\n";
   auto &FileMgr = getCompilerInstance().getFileManager();
diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp
index fe3736c07c3c..d0360696ff9c 100644
--- a/clang/lib/Frontend/InitPreprocessor.cpp
+++ b/clang/lib/Frontend/InitPreprocessor.cpp
@@ -832,11 +832,11 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
 
       unsigned minor = 0;
       if (tuple.getMinor())
-        minor = tuple.getMinor().getValue();
+        minor = tuple.getMinor().value();
 
       unsigned subminor = 0;
       if (tuple.getSubminor())
-        subminor = tuple.getSubminor().getValue();
+        subminor = tuple.getSubminor().value();
 
       Builder.defineMacro("__OBJFW_RUNTIME_ABI__",
                           Twine(tuple.getMajor() * 10000 + minor * 100 +
diff --git a/clang/lib/Headers/hlsl/hlsl_basic_types.h b/clang/lib/Headers/hlsl/hlsl_basic_types.h
index 2069990f5c06..e68715f1a6a4 100644
--- a/clang/lib/Headers/hlsl/hlsl_basic_types.h
+++ b/clang/lib/Headers/hlsl/hlsl_basic_types.h
@@ -27,38 +27,38 @@ typedef long int64_t;
 // built-in vector data types:
 
 #ifdef __HLSL_ENABLE_16_BIT
-typedef int16_t int16_t2 __attribute__((ext_vector_type(2)));
-typedef int16_t int16_t3 __attribute__((ext_vector_type(3)));
-typedef int16_t int16_t4 __attribute__((ext_vector_type(4)));
-typedef uint16_t uint16_t2 __attribute__((ext_vector_type(2)));
-typedef uint16_t uint16_t3 __attribute__((ext_vector_type(3)));
-typedef uint16_t uint16_t4 __attribute__((ext_vector_type(4)));
+typedef vector<int16_t, 2> int16_t2;
+typedef vector<int16_t, 3> int16_t3;
+typedef vector<int16_t, 4> int16_t4;
+typedef vector<uint16_t, 2> uint16_t2;
+typedef vector<uint16_t, 3> uint16_t3;
+typedef vector<uint16_t, 4> uint16_t4;
 #endif
 
-typedef int int2 __attribute__((ext_vector_type(2)));
-typedef int int3 __attribute__((ext_vector_type(3)));
-typedef int int4 __attribute__((ext_vector_type(4)));
-typedef uint uint2 __attribute__((ext_vector_type(2)));
-typedef uint uint3 __attribute__((ext_vector_type(3)));
-typedef uint uint4 __attribute__((ext_vector_type(4)));
-typedef int64_t int64_t2 __attribute__((ext_vector_type(2)));
-typedef int64_t int64_t3 __attribute__((ext_vector_type(3)));
-typedef int64_t int64_t4 __attribute__((ext_vector_type(4)));
-typedef uint64_t uint64_t2 __attribute__((ext_vector_type(2)));
-typedef uint64_t uint64_t3 __attribute__((ext_vector_type(3)));
-typedef uint64_t uint64_t4 __attribute__((ext_vector_type(4)));
+typedef vector<int, 2> int2;
+typedef vector<int, 3> int3;
+typedef vector<int, 4> int4;
+typedef vector<uint, 2> uint2;
+typedef vector<uint, 3> uint3;
+typedef vector<uint, 4> uint4;
+typedef vector<int64_t, 2> int64_t2;
+typedef vector<int64_t, 3> int64_t3;
+typedef vector<int64_t, 4> int64_t4;
+typedef vector<uint64_t, 2> uint64_t2;
+typedef vector<uint64_t, 3> uint64_t3;
+typedef vector<uint64_t, 4> uint64_t4;
 
 #ifdef __HLSL_ENABLE_16_BIT
-typedef half half2 __attribute__((ext_vector_type(2)));
-typedef half half3 __attribute__((ext_vector_type(3)));
-typedef half half4 __attribute__((ext_vector_type(4)));
+typedef vector<half, 2> half2;
+typedef vector<half, 3> half3;
+typedef vector<half, 4> half4;
 #endif
 
-typedef float float2 __attribute__((ext_vector_type(2)));
-typedef float float3 __attribute__((ext_vector_type(3)));
-typedef float float4 __attribute__((ext_vector_type(4)));
-typedef double double2 __attribute__((ext_vector_type(2)));
-typedef double double3 __attribute__((ext_vector_type(3)));
-typedef double double4 __attribute__((ext_vector_type(4)));
+typedef vector<float, 2> float2;
+typedef vector<float, 3> float3;
+typedef vector<float, 4> float4;
+typedef vector<double, 2> double2;
+typedef vector<double, 3> double3;
+typedef vector<double, 4> double4;
 
 #endif //_HLSL_HLSL_BASIC_TYPES_H_
diff --git a/clang/lib/Headers/opencl-c.h b/clang/lib/Headers/opencl-c.h
index ed647d9e9c06..72a6bfeafd6a 100644
--- a/clang/lib/Headers/opencl-c.h
+++ b/clang/lib/Headers/opencl-c.h
@@ -10467,12 +10467,6 @@ float __ovld __cnfn fast_distance(float, float);
 float __ovld __cnfn fast_distance(float2, float2);
 float __ovld __cnfn fast_distance(float3, float3);
 float __ovld __cnfn fast_distance(float4, float4);
-#ifdef cl_khr_fp16
-half __ovld __cnfn fast_distance(half, half);
-half __ovld __cnfn fast_distance(half2, half2);
-half __ovld __cnfn fast_distance(half3, half3);
-half __ovld __cnfn fast_distance(half4, half4);
-#endif //cl_khr_fp16
 
 /**
  * Returns the length of vector p computed as:
@@ -10482,12 +10476,6 @@ float __ovld __cnfn fast_length(float);
 float __ovld __cnfn fast_length(float2);
 float __ovld __cnfn fast_length(float3);
 float __ovld __cnfn fast_length(float4);
-#ifdef cl_khr_fp16
-half __ovld __cnfn fast_length(half);
-half __ovld __cnfn fast_length(half2);
-half __ovld __cnfn fast_length(half3);
-half __ovld __cnfn fast_length(half4);
-#endif //cl_khr_fp16
 
 /**
  * Returns a vector in the same direction as p but with a
@@ -10514,12 +10502,6 @@ float __ovld __cnfn fast_normalize(float);
 float2 __ovld __cnfn fast_normalize(float2);
 float3 __ovld __cnfn fast_normalize(float3);
 float4 __ovld __cnfn fast_normalize(float4);
-#ifdef cl_khr_fp16
-half __ovld __cnfn fast_normalize(half);
-half2 __ovld __cnfn fast_normalize(half2);
-half3 __ovld __cnfn fast_normalize(half3);
-half4 __ovld __cnfn fast_normalize(half4);
-#endif //cl_khr_fp16
 
 // OpenCL v1.1 s6.11.6, v1.2 s6.12.6, v2.0 s6.13.6 - Relational Functions
 
diff --git a/clang/lib/Headers/rdpruintrin.h b/clang/lib/Headers/rdpruintrin.h
new file mode 100644
index 000000000000..89732bb8b3cf
--- /dev/null
+++ b/clang/lib/Headers/rdpruintrin.h
@@ -0,0 +1,57 @@
+/*===---- rdpruintrin.h - RDPRU intrinsics ---------------------------------===
+ *
+ * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+ * See https://llvm.org/LICENSE.txt for license information.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ *
+ *===-----------------------------------------------------------------------===
+ */
+
+#if !defined __X86INTRIN_H
+#error "Never use <rdpruintrin.h> directly; include <x86intrin.h> instead."
+#endif
+
+#ifndef __RDPRUINTRIN_H
+#define __RDPRUINTRIN_H
+
+/* Define the default attributes for the functions in this file. */
+#define __DEFAULT_FN_ATTRS \
+  __attribute__((__always_inline__, __nodebug__,  __target__("rdpru")))
+
+
+/// Reads the content of a processor register.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic corresponds to the <c> RDPRU </c> instruction.
+///
+/// \param reg_id
+///    A processor register identifier.
+static __inline__ unsigned long long __DEFAULT_FN_ATTRS
+__rdpru (int reg_id)
+{
+  return __builtin_ia32_rdpru(reg_id);
+}
+
+#define __RDPRU_MPERF 0
+#define __RDPRU_APERF 1
+
+/// Reads the content of processor register MPERF.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic generates instruction <c> RDPRU </c> to read the value of
+/// register MPERF.
+#define __mperf() __builtin_ia32_rdpru(__RDPRU_MPERF)
+
+/// Reads the content of processor register APERF.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic generates instruction <c> RDPRU </c> to read the value of
+/// register APERF.
+#define __aperf() __builtin_ia32_rdpru(__RDPRU_APERF)
+
+#undef __DEFAULT_FN_ATTRS
+
+#endif /* __RDPRUINTRIN_H */
diff --git a/clang/lib/Headers/stdatomic.h b/clang/lib/Headers/stdatomic.h
index 780bcc2dfea1..3a0b9cc056be 100644
--- a/clang/lib/Headers/stdatomic.h
+++ b/clang/lib/Headers/stdatomic.h
@@ -158,10 +158,6 @@ typedef _Atomic(uintmax_t)          atomic_uintmax_t;
 typedef struct atomic_flag { atomic_bool _Value; } atomic_flag;
 
 #define ATOMIC_FLAG_INIT { 0 }
-#if __cplusplus >= 202002L && !defined(_CLANG_DISABLE_CRT_DEPRECATION_WARNINGS)
-/* ATOMIC_FLAG_INIT was deprecated in C++20 but is not deprecated in C. */
-#pragma clang deprecated(ATOMIC_FLAG_INIT)
-#endif
 
 /* These should be provided by the libc implementation. */
 #ifdef __cplusplus
diff --git a/clang/lib/Headers/x86intrin.h b/clang/lib/Headers/x86intrin.h
index 768d0e56ab05..450fd008dab9 100644
--- a/clang/lib/Headers/x86intrin.h
+++ b/clang/lib/Headers/x86intrin.h
@@ -59,5 +59,9 @@
 #include <clzerointrin.h>
 #endif
 
+#if !(defined(_MSC_VER) || defined(__SCE__)) || __has_feature(modules) ||      \
+    defined(__RDPRU__)
+#include <rdpruintrin.h>
+#endif
 
 #endif /* __X86INTRIN_H */
diff --git a/clang/lib/Lex/DependencyDirectivesScanner.cpp b/clang/lib/Lex/DependencyDirectivesScanner.cpp
index be7b7d6e17b2..567ca81f6ac2 100644
--- a/clang/lib/Lex/DependencyDirectivesScanner.cpp
+++ b/clang/lib/Lex/DependencyDirectivesScanner.cpp
@@ -550,7 +550,7 @@ Scanner::tryLexIdentifierOrSkipLine(const char *&First, const char *const End) {
 StringRef Scanner::lexIdentifier(const char *&First, const char *const End) {
   Optional<StringRef> Id = tryLexIdentifierOrSkipLine(First, End);
   assert(Id && "expected identifier token");
-  return Id.getValue();
+  return Id.value();
 }
 
 bool Scanner::isNextIdentifierOrSkipLine(StringRef Id, const char *&First,
diff --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
index 6820057642be..b3aac9df6546 100644
--- a/clang/lib/Lex/Lexer.cpp
+++ b/clang/lib/Lex/Lexer.cpp
@@ -2392,13 +2392,37 @@ bool Lexer::SkipLineComment(Token &Result, const char *CurPtr,
   //
   // This loop terminates with CurPtr pointing at the newline (or end of buffer)
   // character that ends the line comment.
+
+  // C++23 [lex.phases] p1
+  // Diagnose invalid UTF-8 if the corresponding warning is enabled, emitting a
+  // diagnostic only once per entire ill-formed subsequence to avoid
+  // emiting to many diagnostics (see http://unicode.org/review/pr-121.html).
+  bool UnicodeDecodingAlreadyDiagnosed = false;
+
   char C;
   while (true) {
     C = *CurPtr;
     // Skip over characters in the fast loop.
-    while (C != 0 &&                // Potentially EOF.
-           C != '\n' && C != '\r')  // Newline or DOS-style newline.
+    while (isASCII(C) && C != 0 &&   // Potentially EOF.
+           C != '\n' && C != '\r') { // Newline or DOS-style newline.
       C = *++CurPtr;
+      UnicodeDecodingAlreadyDiagnosed = false;
+    }
+
+    if (!isASCII(C)) {
+      unsigned Length = llvm::getUTF8SequenceSize(
+          (const llvm::UTF8 *)CurPtr, (const llvm::UTF8 *)BufferEnd);
+      if (Length == 0) {
+        if (!UnicodeDecodingAlreadyDiagnosed && !isLexingRawMode())
+          Diag(CurPtr, diag::warn_invalid_utf8_in_comment);
+        UnicodeDecodingAlreadyDiagnosed = true;
+        ++CurPtr;
+      } else {
+        UnicodeDecodingAlreadyDiagnosed = false;
+        CurPtr += Length;
+      }
+      continue;
+    }
 
     const char *NextLine = CurPtr;
     if (C != 0) {
@@ -2665,6 +2689,12 @@ bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr,
   if (C == '/')
     C = *CurPtr++;
 
+  // C++23 [lex.phases] p1
+  // Diagnose invalid UTF-8 if the corresponding warning is enabled, emitting a
+  // diagnostic only once per entire ill-formed subsequence to avoid
+  // emiting to many diagnostics (see http://unicode.org/review/pr-121.html).
+  bool UnicodeDecodingAlreadyDiagnosed = false;
+
   while (true) {
     // Skip over all non-interesting characters until we find end of buffer or a
     // (probably ending) '/' character.
@@ -2673,14 +2703,21 @@ bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr,
         // doesn't check for '\0'.
         !(PP && PP->getCodeCompletionFileLoc() == FileLoc)) {
       // While not aligned to a 16-byte boundary.
-      while (C != '/' && ((intptr_t)CurPtr & 0x0F) != 0)
+      while (C != '/' && (intptr_t)CurPtr % 16 != 0) {
+        if (!isASCII(C))
+          goto MultiByteUTF8;
         C = *CurPtr++;
-
+      }
       if (C == '/') goto FoundSlash;
 
 #ifdef __SSE2__
       __m128i Slashes = _mm_set1_epi8('/');
-      while (CurPtr+16 <= BufferEnd) {
+      while (CurPtr + 16 < BufferEnd) {
+        int Mask = _mm_movemask_epi8(*(const __m128i *)CurPtr);
+        if (LLVM_UNLIKELY(Mask != 0)) {
+          goto MultiByteUTF8;
+        }
+        // look for slashes
         int cmp = _mm_movemask_epi8(_mm_cmpeq_epi8(*(const __m128i*)CurPtr,
                                     Slashes));
         if (cmp != 0) {
@@ -2693,21 +2730,38 @@ bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr,
         CurPtr += 16;
       }
 #elif __ALTIVEC__
+      __vector unsigned char LongUTF = {0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+                                        0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+                                        0x80, 0x80, 0x80, 0x80};
       __vector unsigned char Slashes = {
         '/', '/', '/', '/',  '/', '/', '/', '/',
         '/', '/', '/', '/',  '/', '/', '/', '/'
       };
-      while (CurPtr + 16 <= BufferEnd &&
-             !vec_any_eq(*(const __vector unsigned char *)CurPtr, Slashes))
+      while (CurPtr + 16 < BufferEnd) {
+        if (LLVM_UNLIKELY(
+                vec_any_ge(*(const __vector unsigned char *)CurPtr, LongUTF)))
+          goto MultiByteUTF8;
+        if (vec_any_eq(*(const __vector unsigned char *)CurPtr, Slashes)) {
+          break;
+        }
         CurPtr += 16;
+      }
+
 #else
-      // Scan for '/' quickly.  Many block comments are very large.
-      while (CurPtr[0] != '/' &&
-             CurPtr[1] != '/' &&
-             CurPtr[2] != '/' &&
-             CurPtr[3] != '/' &&
-             CurPtr+4 < BufferEnd) {
-        CurPtr += 4;
+      while (CurPtr + 16 < BufferEnd) {
+        bool HasNonASCII = false;
+        for (unsigned I = 0; I < 16; ++I)
+          HasNonASCII |= !isASCII(CurPtr[I]);
+
+        if (LLVM_UNLIKELY(HasNonASCII))
+          goto MultiByteUTF8;
+
+        bool HasSlash = false;
+        for (unsigned I = 0; I < 16; ++I)
+          HasSlash |= CurPtr[I] == '/';
+        if (HasSlash)
+          break;
+        CurPtr += 16;
       }
 #endif
 
@@ -2715,9 +2769,30 @@ bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr,
       C = *CurPtr++;
     }
 
-    // Loop to scan the remainder.
-    while (C != '/' && C != '\0')
+    // Loop to scan the remainder, warning on invalid UTF-8
+    // if the corresponding warning is enabled, emitting a diagnostic only once
+    // per sequence that cannot be decoded.
+    while (C != '/' && C != '\0') {
+      if (isASCII(C)) {
+        UnicodeDecodingAlreadyDiagnosed = false;
+        C = *CurPtr++;
+        continue;
+      }
+    MultiByteUTF8:
+      // CurPtr is 1 code unit past C, so to decode
+      // the codepoint, we need to read from the previous position.
+      unsigned Length = llvm::getUTF8SequenceSize(
+          (const llvm::UTF8 *)CurPtr - 1, (const llvm::UTF8 *)BufferEnd);
+      if (Length == 0) {
+        if (!UnicodeDecodingAlreadyDiagnosed && !isLexingRawMode())
+          Diag(CurPtr - 1, diag::warn_invalid_utf8_in_comment);
+        UnicodeDecodingAlreadyDiagnosed = true;
+      } else {
+        UnicodeDecodingAlreadyDiagnosed = false;
+        CurPtr += Length - 1;
+      }
       C = *CurPtr++;
+    }
 
     if (C == '/') {
   FoundSlash:
@@ -3212,7 +3287,10 @@ llvm::Optional<uint32_t> Lexer::tryReadNumericUCN(const char *&StartPtr,
   }
 
   if (Delimited && PP) {
-    Diag(BufferPtr, diag::ext_delimited_escape_sequence) << /*delimited*/ 0;
+    Diag(BufferPtr, PP->getLangOpts().CPlusPlus2b
+                        ? diag::warn_cxx2b_delimited_escape_sequence
+                        : diag::ext_delimited_escape_sequence)
+        << /*delimited*/ 0 << (PP->getLangOpts().CPlusPlus ? 1 : 0);
   }
 
   if (Result) {
@@ -3296,7 +3374,10 @@ llvm::Optional<uint32_t> Lexer::tryReadNamedUCN(const char *&StartPtr,
   }
 
   if (Diagnose && PP && !LooseMatch)
-    Diag(BufferPtr, diag::ext_delimited_escape_sequence) << /*named*/ 1;
+    Diag(BufferPtr, PP->getLangOpts().CPlusPlus2b
+                        ? diag::warn_cxx2b_delimited_escape_sequence
+                        : diag::ext_delimited_escape_sequence)
+        << /*named*/ 1 << (PP->getLangOpts().CPlusPlus ? 1 : 0);
 
   if (LooseMatch)
     Res = LooseMatch->CodePoint;
diff --git a/clang/lib/Lex/LiteralSupport.cpp b/clang/lib/Lex/LiteralSupport.cpp
index ebf30c9f01a9..53635a7385ec 100644
--- a/clang/lib/Lex/LiteralSupport.cpp
+++ b/clang/lib/Lex/LiteralSupport.cpp
@@ -311,8 +311,9 @@ static unsigned ProcessCharEscape(const char *ThisTokBegin,
           << tok::r_brace;
     else if (!HadError) {
       Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf,
-           diag::ext_delimited_escape_sequence)
-          << /*delimited*/ 0;
+           Features.CPlusPlus2b ? diag::warn_cxx2b_delimited_escape_sequence
+                                : diag::ext_delimited_escape_sequence)
+          << /*delimited*/ 0 << (Features.CPlusPlus ? 1 : 0);
     }
   }
 
@@ -641,8 +642,9 @@ static bool ProcessUCNEscape(const char *ThisTokBegin, const char *&ThisTokBuf,
 
   if ((IsDelimitedEscapeSequence || IsNamedEscapeSequence) && Diags)
     Diag(Diags, Features, Loc, ThisTokBegin, UcnBegin, ThisTokBuf,
-         diag::ext_delimited_escape_sequence)
-        << (IsNamedEscapeSequence ? 1 : 0);
+         Features.CPlusPlus2b ? diag::warn_cxx2b_delimited_escape_sequence
+                              : diag::ext_delimited_escape_sequence)
+        << (IsNamedEscapeSequence ? 1 : 0) << (Features.CPlusPlus ? 1 : 0);
 
   return true;
 }
diff --git a/clang/lib/Lex/MacroInfo.cpp b/clang/lib/Lex/MacroInfo.cpp
index 310b95f36771..eae12beb6244 100644
--- a/clang/lib/Lex/MacroInfo.cpp
+++ b/clang/lib/Lex/MacroInfo.cpp
@@ -213,7 +213,7 @@ MacroDirective::DefInfo MacroDirective::getDefinition() {
       isPublic = VisMD->isPublic();
   }
 
-  return DefInfo(nullptr, UndefLoc, !isPublic || isPublic.getValue());
+  return DefInfo(nullptr, UndefLoc, !isPublic || isPublic.value());
 }
 
 const MacroDirective::DefInfo
diff --git a/clang/lib/Lex/ModuleMap.cpp b/clang/lib/Lex/ModuleMap.cpp
index c791e3e4e5ca..57e344622f25 100644
--- a/clang/lib/Lex/ModuleMap.cpp
+++ b/clang/lib/Lex/ModuleMap.cpp
@@ -1219,8 +1219,8 @@ void ModuleMap::resolveHeaderDirectives(
     Module *Mod, llvm::Optional<const FileEntry *> File) const {
   bool NeedsFramework = false;
   SmallVector<Module::UnresolvedHeaderDirective, 1> NewHeaders;
-  const auto Size = File ? File.getValue()->getSize() : 0;
-  const auto ModTime = File ? File.getValue()->getModificationTime() : 0;
+  const auto Size = File ? File.value()->getSize() : 0;
+  const auto ModTime = File ? File.value()->getModificationTime() : 0;
 
   for (auto &Header : Mod->UnresolvedHeaders) {
     if (File && ((Header.ModTime && Header.ModTime != ModTime) ||
diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp
index 4dcef01e3e4c..352e1f217819 100644
--- a/clang/lib/Lex/PPDirectives.cpp
+++ b/clang/lib/Lex/PPDirectives.cpp
@@ -1983,6 +1983,10 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
     EnterAnnotationToken(SourceRange(HashLoc, EndLoc),
                          tok::annot_module_begin, Action.ModuleForHeader);
     break;
+  case ImportAction::HeaderUnitImport:
+    EnterAnnotationToken(SourceRange(HashLoc, EndLoc), tok::annot_header_unit,
+                         Action.ModuleForHeader);
+    break;
   case ImportAction::ModuleImport:
     EnterAnnotationToken(SourceRange(HashLoc, EndLoc),
                          tok::annot_module_include, Action.ModuleForHeader);
@@ -2191,6 +2195,17 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
   // known to have no effect beyond its effect on module visibility -- that is,
   // if it's got an include guard that is already defined, set to Import if it
   // is a modular header we've already built and should import.
+
+  // For C++20 Modules
+  // [cpp.include]/7 If the header identified by the header-name denotes an
+  // importable header, it is implementation-defined whether the #include
+  // preprocessing directive is instead replaced by an import directive.
+  // For this implementation, the translation is permitted when we are parsing
+  // the Global Module Fragment, and not otherwise (the cases where it would be
+  // valid to replace an include with an import are highly constrained once in
+  // named module purview; this choice avoids considerable complexity in
+  // determining valid cases).
+
   enum { Enter, Import, Skip, IncludeLimitReached } Action = Enter;
 
   if (PPOpts->SingleFileParseMode)
@@ -2203,13 +2218,34 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
       alreadyIncluded(*File))
     Action = IncludeLimitReached;
 
+  bool MaybeTranslateInclude = Action == Enter && File && SuggestedModule &&
+                               !isForModuleBuilding(SuggestedModule.getModule(),
+                                                    getLangOpts().CurrentModule,
+                                                    getLangOpts().ModuleName);
+
+  // FIXME: We do not have a good way to disambiguate C++ clang modules from
+  // C++ standard modules (other than use/non-use of Header Units).
+  Module *SM = SuggestedModule.getModule();
+  // Maybe a usable Header Unit
+  bool UsableHeaderUnit = false;
+  if (getLangOpts().CPlusPlusModules && SM && SM->isHeaderUnit()) {
+    if (TrackGMFState.inGMF() || IsImportDecl)
+      UsableHeaderUnit = true;
+    else if (!IsImportDecl) {
+      // This is a Header Unit that we do not include-translate
+      SuggestedModule = ModuleMap::KnownHeader();
+      SM = nullptr;
+    }
+  }
+  // Maybe a usable clang header module.
+  bool UsableHeaderModule =
+      (getLangOpts().CPlusPlusModules || getLangOpts().Modules) && SM &&
+      !SM->isHeaderUnit();
+
   // Determine whether we should try to import the module for this #include, if
   // there is one. Don't do so if precompiled module support is disabled or we
   // are processing this module textually (because we're building the module).
-  if (Action == Enter && File && SuggestedModule && getLangOpts().Modules &&
-      !isForModuleBuilding(SuggestedModule.getModule(),
-                           getLangOpts().CurrentModule,
-                           getLangOpts().ModuleName)) {
+  if (MaybeTranslateInclude && (UsableHeaderUnit || UsableHeaderModule)) {
     // If this include corresponds to a module but that module is
     // unavailable, diagnose the situation and bail out.
     // FIXME: Remove this; loadModule does the same check (but produces
@@ -2226,7 +2262,7 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
     // FIXME: Should we have a second loadModule() overload to avoid this
     // extra lookup step?
     SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
-    for (Module *Mod = SuggestedModule.getModule(); Mod; Mod = Mod->Parent)
+    for (Module *Mod = SM; Mod; Mod = Mod->Parent)
       Path.push_back(std::make_pair(getIdentifierInfo(Mod->Name),
                                     FilenameTok.getLocation()));
     std::reverse(Path.begin(), Path.end());
@@ -2293,9 +2329,12 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
   // Ask HeaderInfo if we should enter this #include file.  If not, #including
   // this file will have no effect.
   if (Action == Enter && File &&
-      !HeaderInfo.ShouldEnterIncludeFile(
-          *this, &File->getFileEntry(), EnterOnce, getLangOpts().Modules,
-          SuggestedModule.getModule(), IsFirstIncludeOfFile)) {
+      !HeaderInfo.ShouldEnterIncludeFile(*this, &File->getFileEntry(),
+                                         EnterOnce, getLangOpts().Modules, SM,
+                                         IsFirstIncludeOfFile)) {
+    // C++ standard modules:
+    // If we are not in the GMF, then we textually include only
+    // clang modules:
     // Even if we've already preprocessed this header once and know that we
     // don't need to see its contents again, we still need to import it if it's
     // modular because we might not have imported it from this submodule before.
@@ -2303,7 +2342,10 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
     // FIXME: We don't do this when compiling a PCH because the AST
     // serialization layer can't cope with it. This means we get local
     // submodule visibility semantics wrong in that case.
-    Action = (SuggestedModule && !getLangOpts().CompilingPCH) ? Import : Skip;
+    if (UsableHeaderUnit && !getLangOpts().CompilingPCH)
+      Action = TrackGMFState.inGMF() ? Import : Skip;
+    else
+      Action = (SuggestedModule && !getLangOpts().CompilingPCH) ? Import : Skip;
   }
 
   // Check for circular inclusion of the main file.
@@ -2440,8 +2482,8 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
   switch (Action) {
   case Skip:
     // If we don't need to enter the file, stop now.
-    if (Module *M = SuggestedModule.getModule())
-      return {ImportAction::SkippedModuleImport, M};
+    if (SM)
+      return {ImportAction::SkippedModuleImport, SM};
     return {ImportAction::None};
 
   case IncludeLimitReached:
@@ -2451,16 +2493,15 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
 
   case Import: {
     // If this is a module import, make it visible if needed.
-    Module *M = SuggestedModule.getModule();
-    assert(M && "no module to import");
+    assert(SM && "no module to import");
 
-    makeModuleVisible(M, EndLoc);
+    makeModuleVisible(SM, EndLoc);
 
     if (IncludeTok.getIdentifierInfo()->getPPKeywordID() ==
         tok::pp___include_macros)
       return {ImportAction::None};
 
-    return {ImportAction::ModuleImport, M};
+    return {ImportAction::ModuleImport, SM};
   }
 
   case Enter:
@@ -2492,13 +2533,14 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
     return {ImportAction::None};
 
   // Determine if we're switching to building a new submodule, and which one.
-  if (auto *M = SuggestedModule.getModule()) {
-    if (M->getTopLevelModule()->ShadowingModule) {
+  // This does not apply for C++20 modules header units.
+  if (SM && !SM->isHeaderUnit()) {
+    if (SM->getTopLevelModule()->ShadowingModule) {
       // We are building a submodule that belongs to a shadowed module. This
       // means we find header files in the shadowed module.
-      Diag(M->DefinitionLoc, diag::err_module_build_shadowed_submodule)
-        << M->getFullModuleName();
-      Diag(M->getTopLevelModule()->ShadowingModule->DefinitionLoc,
+      Diag(SM->DefinitionLoc, diag::err_module_build_shadowed_submodule)
+          << SM->getFullModuleName();
+      Diag(SM->getTopLevelModule()->ShadowingModule->DefinitionLoc,
            diag::note_previous_definition);
       return {ImportAction::None};
     }
@@ -2511,22 +2553,22 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
     // that PCH, which means we should enter the submodule. We need to teach
     // the AST serialization layer to deal with the resulting AST.
     if (getLangOpts().CompilingPCH &&
-        isForModuleBuilding(M, getLangOpts().CurrentModule,
+        isForModuleBuilding(SM, getLangOpts().CurrentModule,
                             getLangOpts().ModuleName))
       return {ImportAction::None};
 
     assert(!CurLexerSubmodule && "should not have marked this as a module yet");
-    CurLexerSubmodule = M;
+    CurLexerSubmodule = SM;
 
     // Let the macro handling code know that any future macros are within
     // the new submodule.
-    EnterSubmodule(M, EndLoc, /*ForPragma*/false);
+    EnterSubmodule(SM, EndLoc, /*ForPragma*/ false);
 
     // Let the parser know that any future declarations are within the new
     // submodule.
     // FIXME: There's no point doing this if we're handling a #__include_macros
     // directive.
-    return {ImportAction::ModuleBegin, M};
+    return {ImportAction::ModuleBegin, SM};
   }
 
   assert(!IsImportDecl && "failed to diagnose missing module for import decl");
diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index bf46e5422bc8..f3be2107f985 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -1326,10 +1326,10 @@ already_lexed:
         // The last ')' has been reached; return the value if one found or
         // a diagnostic and a dummy value.
         if (Result) {
-          OS << Result.getValue();
+          OS << Result.value();
           // For strict conformance to __has_cpp_attribute rules, use 'L'
           // suffix for dated literals.
-          if (Result.getValue() > 1)
+          if (Result.value() > 1)
             OS << 'L';
         } else {
           OS << 0;
diff --git a/clang/lib/Lex/PreprocessingRecord.cpp b/clang/lib/Lex/PreprocessingRecord.cpp
index 673ef637e396..2146a7c04217 100644
--- a/clang/lib/Lex/PreprocessingRecord.cpp
+++ b/clang/lib/Lex/PreprocessingRecord.cpp
@@ -115,7 +115,7 @@ bool PreprocessingRecord::isEntityInFileID(iterator PPEI, FileID FID) {
     Optional<bool> IsInFile =
         ExternalSource->isPreprocessedEntityInFileID(LoadedIndex, FID);
     if (IsInFile)
-      return IsInFile.getValue();
+      return IsInFile.value();
 
     // The external source did not provide a definite answer, go and deserialize
     // the entity to check it.
diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 281f01fb28a4..5310db3c882b 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -941,6 +941,9 @@ void Preprocessor::Lex(Token &Result) {
 
   // Update ImportSeqState to track our position within a C++20 import-seq
   // if this token is being produced as a result of phase 4 of translation.
+  // Update TrackGMFState to decide if we are currently in a Global Module
+  // Fragment. GMF state updates should precede ImportSeq ones, since GMF state
+  // depends on the prevailing ImportSeq state in two cases.
   if (getLangOpts().CPlusPlusModules && LexLevel == 1 &&
       !Result.getFlag(Token::IsReinjected)) {
     switch (Result.getKind()) {
@@ -953,7 +956,11 @@ void Preprocessor::Lex(Token &Result) {
     case tok::r_brace:
       ImportSeqState.handleCloseBrace();
       break;
+    // This token is injected to represent the translation of '#include "a.h"'
+    // into "import a.h;". Mimic the notional ';'.
+    case tok::annot_module_include:
     case tok::semi:
+      TrackGMFState.handleSemi();
       ImportSeqState.handleSemi();
       break;
     case tok::header_name:
@@ -961,10 +968,12 @@ void Preprocessor::Lex(Token &Result) {
       ImportSeqState.handleHeaderName();
       break;
     case tok::kw_export:
+      TrackGMFState.handleExport();
       ImportSeqState.handleExport();
       break;
     case tok::identifier:
       if (Result.getIdentifierInfo()->isModulesImport()) {
+        TrackGMFState.handleImport(ImportSeqState.afterTopLevelSeq());
         ImportSeqState.handleImport();
         if (ImportSeqState.afterImportSeq()) {
           ModuleImportLoc = Result.getLocation();
@@ -973,9 +982,13 @@ void Preprocessor::Lex(Token &Result) {
           CurLexerKind = CLK_LexAfterModuleImport;
         }
         break;
+      } else if (Result.getIdentifierInfo() == getIdentifierInfo("module")) {
+        TrackGMFState.handleModule(ImportSeqState.afterTopLevelSeq());
+        break;
       }
       LLVM_FALLTHROUGH;
     default:
+      TrackGMFState.handleMisc();
       ImportSeqState.handleMisc();
       break;
     }
@@ -1222,6 +1235,7 @@ bool Preprocessor::LexAfterModuleImport(Token &Result) {
       LLVM_FALLTHROUGH;
 
     case ImportAction::ModuleImport:
+    case ImportAction::HeaderUnitImport:
     case ImportAction::SkippedModuleImport:
       // We chose to import (or textually enter) the file. Convert the
       // header-name token into a header unit annotation token.
diff --git a/clang/lib/Parse/ParseOpenMP.cpp b/clang/lib/Parse/ParseOpenMP.cpp
index 08dccf9e43f7..5f53f9d684e7 100644
--- a/clang/lib/Parse/ParseOpenMP.cpp
+++ b/clang/lib/Parse/ParseOpenMP.cpp
@@ -1884,11 +1884,11 @@ void Parser::ParseOMPDeclareTargetClauses(
         if (DevTypeData) {
           if (DeviceTypeLoc.isValid()) {
             // We already saw another device_type clause, diagnose it.
-            Diag(DevTypeData.getValue().Loc,
+            Diag(DevTypeData.value().Loc,
                  diag::warn_omp_more_one_device_type_clause);
             break;
           }
-          switch (static_cast<OpenMPDeviceType>(DevTypeData.getValue().Type)) {
+          switch (static_cast<OpenMPDeviceType>(DevTypeData.value().Type)) {
           case OMPC_DEVICE_TYPE_any:
             DTCI.DT = OMPDeclareTargetDeclAttr::DT_Any;
             break;
@@ -3634,20 +3634,20 @@ OMPClause *Parser::ParseOpenMPSimpleClause(OpenMPClauseKind Kind,
   if (!Val || ParseOnly)
     return nullptr;
   if (getLangOpts().OpenMP < 51 && Kind == OMPC_default &&
-      (static_cast<DefaultKind>(Val.getValue().Type) == OMP_DEFAULT_private ||
-       static_cast<DefaultKind>(Val.getValue().Type) ==
+      (static_cast<DefaultKind>(Val.value().Type) == OMP_DEFAULT_private ||
+       static_cast<DefaultKind>(Val.value().Type) ==
            OMP_DEFAULT_firstprivate)) {
-    Diag(Val.getValue().LOpen, diag::err_omp_invalid_dsa)
-        << getOpenMPClauseName(static_cast<DefaultKind>(Val.getValue().Type) ==
+    Diag(Val.value().LOpen, diag::err_omp_invalid_dsa)
+        << getOpenMPClauseName(static_cast<DefaultKind>(Val.value().Type) ==
                                        OMP_DEFAULT_private
                                    ? OMPC_private
                                    : OMPC_firstprivate)
         << getOpenMPClauseName(OMPC_default) << "5.1";
     return nullptr;
   }
-  return Actions.ActOnOpenMPSimpleClause(
-      Kind, Val.getValue().Type, Val.getValue().TypeLoc, Val.getValue().LOpen,
-      Val.getValue().Loc, Val.getValue().RLoc);
+  return Actions.ActOnOpenMPSimpleClause(Kind, Val.value().Type,
+                                         Val.value().TypeLoc, Val.value().LOpen,
+                                         Val.value().Loc, Val.value().RLoc);
 }
 
 /// Parsing of OpenMP clauses like 'ordered'.
diff --git a/clang/lib/Parse/Parser.cpp b/clang/lib/Parse/Parser.cpp
index 6f63d01bc8ad..ab8748c2c63d 100644
--- a/clang/lib/Parse/Parser.cpp
+++ b/clang/lib/Parse/Parser.cpp
@@ -663,12 +663,22 @@ bool Parser::ParseTopLevelDecl(DeclGroupPtrTy &Result,
     return false;
   }
 
-  case tok::annot_module_include:
-    Actions.ActOnModuleInclude(Tok.getLocation(),
-                               reinterpret_cast<Module *>(
-                                   Tok.getAnnotationValue()));
+  case tok::annot_module_include: {
+    auto Loc = Tok.getLocation();
+    Module *Mod = reinterpret_cast<Module *>(Tok.getAnnotationValue());
+    // FIXME: We need a better way to disambiguate C++ clang modules and
+    // standard C++ modules.
+    if (!getLangOpts().CPlusPlusModules || !Mod->isHeaderUnit())
+      Actions.ActOnModuleInclude(Loc, Mod);
+    else {
+      DeclResult Import =
+          Actions.ActOnModuleImport(Loc, SourceLocation(), Loc, Mod);
+      Decl *ImportDecl = Import.isInvalid() ? nullptr : Import.get();
+      Result = Actions.ConvertDeclToDeclGroup(ImportDecl);
+    }
     ConsumeAnnotationToken();
     return false;
+  }
 
   case tok::annot_module_begin:
     Actions.ActOnModuleBegin(Tok.getLocation(), reinterpret_cast<Module *>(
diff --git a/clang/lib/Sema/HLSLExternalSemaSource.cpp b/clang/lib/Sema/HLSLExternalSemaSource.cpp
new file mode 100644
index 000000000000..56c2dd40bd9a
--- /dev/null
+++ b/clang/lib/Sema/HLSLExternalSemaSource.cpp
@@ -0,0 +1,96 @@
+//===--- HLSLExternalSemaSource.cpp - HLSL Sema Source --------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Sema/HLSLExternalSemaSource.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/Basic/AttrKinds.h"
+#include "clang/Sema/Sema.h"
+
+using namespace clang;
+
+HLSLExternalSemaSource::~HLSLExternalSemaSource() {}
+
+void HLSLExternalSemaSource::InitializeSema(Sema &S) {
+  SemaPtr = &S;
+  ASTContext &AST = SemaPtr->getASTContext();
+  IdentifierInfo &HLSL = AST.Idents.get("hlsl", tok::TokenKind::identifier);
+  HLSLNamespace =
+      NamespaceDecl::Create(AST, AST.getTranslationUnitDecl(), false,
+                            SourceLocation(), SourceLocation(), &HLSL, nullptr);
+  HLSLNamespace->setImplicit(true);
+  AST.getTranslationUnitDecl()->addDecl(HLSLNamespace);
+  defineHLSLVectorAlias();
+
+  // This adds a `using namespace hlsl` directive. In DXC, we don't put HLSL's
+  // built in types inside a namespace, but we are planning to change that in
+  // the near future. In order to be source compatible older versions of HLSL
+  // will need to implicitly use the hlsl namespace. For now in clang everything
+  // will get added to the namespace, and we can remove the using directive for
+  // future language versions to match HLSL's evolution.
+  auto *UsingDecl = UsingDirectiveDecl::Create(
+      AST, AST.getTranslationUnitDecl(), SourceLocation(), SourceLocation(),
+      NestedNameSpecifierLoc(), SourceLocation(), HLSLNamespace,
+      AST.getTranslationUnitDecl());
+
+  AST.getTranslationUnitDecl()->addDecl(UsingDecl);
+}
+
+void HLSLExternalSemaSource::defineHLSLVectorAlias() {
+  ASTContext &AST = SemaPtr->getASTContext();
+
+  llvm::SmallVector<NamedDecl *> TemplateParams;
+
+  auto *TypeParam = TemplateTypeParmDecl::Create(
+      AST, HLSLNamespace, SourceLocation(), SourceLocation(), 0, 0,
+      &AST.Idents.get("element", tok::TokenKind::identifier), false, false);
+  TypeParam->setDefaultArgument(AST.getTrivialTypeSourceInfo(AST.FloatTy));
+
+  TemplateParams.emplace_back(TypeParam);
+
+  auto *SizeParam = NonTypeTemplateParmDecl::Create(
+      AST, HLSLNamespace, SourceLocation(), SourceLocation(), 0, 1,
+      &AST.Idents.get("element_count", tok::TokenKind::identifier), AST.IntTy,
+      false, AST.getTrivialTypeSourceInfo(AST.IntTy));
+  Expr *LiteralExpr =
+      IntegerLiteral::Create(AST, llvm::APInt(AST.getIntWidth(AST.IntTy), 4),
+                             AST.IntTy, SourceLocation());
+  SizeParam->setDefaultArgument(LiteralExpr);
+  TemplateParams.emplace_back(SizeParam);
+
+  auto *ParamList =
+      TemplateParameterList::Create(AST, SourceLocation(), SourceLocation(),
+                                    TemplateParams, SourceLocation(), nullptr);
+
+  IdentifierInfo &II = AST.Idents.get("vector", tok::TokenKind::identifier);
+
+  QualType AliasType = AST.getDependentSizedExtVectorType(
+      AST.getTemplateTypeParmType(0, 0, false, TypeParam),
+      DeclRefExpr::Create(
+          AST, NestedNameSpecifierLoc(), SourceLocation(), SizeParam, false,
+          DeclarationNameInfo(SizeParam->getDeclName(), SourceLocation()),
+          AST.IntTy, VK_LValue),
+      SourceLocation());
+
+  auto *Record = TypeAliasDecl::Create(AST, HLSLNamespace, SourceLocation(),
+                                       SourceLocation(), &II,
+                                       AST.getTrivialTypeSourceInfo(AliasType));
+  Record->setImplicit(true);
+
+  auto *Template =
+      TypeAliasTemplateDecl::Create(AST, HLSLNamespace, SourceLocation(),
+                                    Record->getIdentifier(), ParamList, Record);
+
+  Record->setDescribedAliasTemplate(Template);
+  Template->setImplicit(true);
+  Template->setLexicalDeclContext(Record->getDeclContext());
+  HLSLNamespace->addDecl(Template);
+}
diff --git a/clang/lib/Sema/SemaCUDA.cpp b/clang/lib/Sema/SemaCUDA.cpp
index 8f8144d658d8..185ccebe2717 100644
--- a/clang/lib/Sema/SemaCUDA.cpp
+++ b/clang/lib/Sema/SemaCUDA.cpp
@@ -381,13 +381,13 @@ bool Sema::inferCUDATargetForImplicitSpecialMember(CXXRecordDecl *ClassDecl,
       InferredTarget = BaseMethodTarget;
     } else {
       bool ResolutionError = resolveCalleeCUDATargetConflict(
-          InferredTarget.getValue(), BaseMethodTarget,
+          InferredTarget.value(), BaseMethodTarget,
           InferredTarget.getPointer());
       if (ResolutionError) {
         if (Diagnose) {
           Diag(ClassDecl->getLocation(),
                diag::note_implicit_member_target_infer_collision)
-              << (unsigned)CSM << InferredTarget.getValue() << BaseMethodTarget;
+              << (unsigned)CSM << InferredTarget.value() << BaseMethodTarget;
         }
         MemberDecl->addAttr(CUDAInvalidTargetAttr::CreateImplicit(Context));
         return true;
@@ -425,14 +425,13 @@ bool Sema::inferCUDATargetForImplicitSpecialMember(CXXRecordDecl *ClassDecl,
       InferredTarget = FieldMethodTarget;
     } else {
       bool ResolutionError = resolveCalleeCUDATargetConflict(
-          InferredTarget.getValue(), FieldMethodTarget,
+          InferredTarget.value(), FieldMethodTarget,
           InferredTarget.getPointer());
       if (ResolutionError) {
         if (Diagnose) {
           Diag(ClassDecl->getLocation(),
                diag::note_implicit_member_target_infer_collision)
-              << (unsigned)CSM << InferredTarget.getValue()
-              << FieldMethodTarget;
+              << (unsigned)CSM << InferredTarget.value() << FieldMethodTarget;
         }
         MemberDecl->addAttr(CUDAInvalidTargetAttr::CreateImplicit(Context));
         return true;
@@ -445,9 +444,9 @@ bool Sema::inferCUDATargetForImplicitSpecialMember(CXXRecordDecl *ClassDecl,
   // it's the least restrictive option that can be invoked from any target.
   bool NeedsH = true, NeedsD = true;
   if (InferredTarget) {
-    if (InferredTarget.getValue() == CFT_Device)
+    if (InferredTarget.value() == CFT_Device)
       NeedsH = false;
-    else if (InferredTarget.getValue() == CFT_Host)
+    else if (InferredTarget.value() == CFT_Host)
       NeedsD = false;
   }
 
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 79420cc27699..aed1d9befe2b 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -109,6 +109,11 @@ SourceLocation Sema::getLocationOfStringLiteralByte(const StringLiteral *SL,
                                Context.getTargetInfo());
 }
 
+static constexpr unsigned short combineFAPK(Sema::FormatArgumentPassingKind A,
+                                            Sema::FormatArgumentPassingKind B) {
+  return (A << 8) | B;
+}
+
 /// Checks that a call expression's argument count is at least the desired
 /// number. This is useful when doing custom type-checking on a variadic
 /// function. Returns true on error.
@@ -1875,7 +1880,7 @@ static ExprResult SemaBuiltinLaunder(Sema &S, CallExpr *TheCall) {
   }();
   if (DiagSelect) {
     S.Diag(TheCall->getBeginLoc(), diag::err_builtin_launder_invalid_arg)
-        << DiagSelect.getValue() << TheCall->getSourceRange();
+        << DiagSelect.value() << TheCall->getSourceRange();
     return ExprError();
   }
 
@@ -2408,7 +2413,7 @@ Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID,
     bool ReturnsPointer = BuiltinID == Builtin::BIaddressof ||
                           BuiltinID == Builtin::BI__addressof;
     if (!(Param->isReferenceType() &&
-          (ReturnsPointer ? Result->isPointerType()
+          (ReturnsPointer ? Result->isAnyPointerType()
                           : Result->isReferenceType()) &&
           Context.hasSameUnqualifiedType(Param->getPointeeType(),
                                          Result->getPointeeType()))) {
@@ -5403,10 +5408,16 @@ bool Sema::CheckX86BuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
 /// Returns true when the format fits the function and the FormatStringInfo has
 /// been populated.
 bool Sema::getFormatStringInfo(const FormatAttr *Format, bool IsCXXMember,
-                               FormatStringInfo *FSI) {
-  FSI->HasVAListArg = Format->getFirstArg() == 0;
+                               bool IsVariadic, FormatStringInfo *FSI) {
+  if (Format->getFirstArg() == 0)
+    FSI->ArgPassingKind = FAPK_VAList;
+  else if (IsVariadic)
+    FSI->ArgPassingKind = FAPK_Variadic;
+  else
+    FSI->ArgPassingKind = FAPK_Fixed;
   FSI->FormatIdx = Format->getFormatIdx() - 1;
-  FSI->FirstDataArg = FSI->HasVAListArg ? 0 : Format->getFirstArg() - 1;
+  FSI->FirstDataArg =
+      FSI->ArgPassingKind == FAPK_VAList ? 0 : Format->getFirstArg() - 1;
 
   // The way the format attribute works in GCC, the implicit this argument
   // of member functions is counted. However, it doesn't appear in our own
@@ -5461,7 +5472,7 @@ static void CheckNonNullArgument(Sema &S,
 bool Sema::GetFormatNSStringIdx(const FormatAttr *Format, unsigned &Idx) {
   FormatStringInfo FSI;
   if ((GetFormatStringType(Format) == FST_NSString) &&
-      getFormatStringInfo(Format, false, &FSI)) {
+      getFormatStringInfo(Format, false, true, &FSI)) {
     Idx = FSI.FormatIdx;
     return true;
   }
@@ -5615,6 +5626,40 @@ static void CheckNonNullArguments(Sema &S,
   }
 }
 
+// 16 byte ByVal alignment not due to a vector member is not honoured by XL
+// on AIX. Emit a warning here that users are generating binary incompatible
+// code to be safe.
+// Here we try to get information about the alignment of the struct member
+// from the struct passed to the caller function. We only warn when the struct
+// is passed byval, hence the series of checks and early returns if we are a not
+// passing a struct byval.
+void Sema::checkAIXMemberAlignment(SourceLocation Loc, const Expr *Arg) {
+  const auto *ICE = dyn_cast<ImplicitCastExpr>(Arg->IgnoreParens());
+  if (!ICE)
+    return;
+
+  const auto *DR = dyn_cast<DeclRefExpr>(ICE->getSubExpr());
+  if (!DR)
+    return;
+
+  const auto *PD = dyn_cast<ParmVarDecl>(DR->getDecl());
+  if (!PD || !PD->getType()->isRecordType())
+    return;
+
+  QualType ArgType = Arg->getType();
+  for (const FieldDecl *FD :
+       ArgType->castAs<RecordType>()->getDecl()->fields()) {
+    if (const auto *AA = FD->getAttr<AlignedAttr>()) {
+      CharUnits Alignment =
+          Context.toCharUnitsFromBits(AA->getAlignment(Context));
+      if (Alignment.getQuantity() == 16) {
+        Diag(FD->getLocation(), diag::warn_not_xl_compatible) << FD;
+        Diag(Loc, diag::note_misaligned_member_used_here) << PD;
+      }
+    }
+  }
+}
+
 /// Warn if a pointer or reference argument passed to a function points to an
 /// object that is less aligned than the parameter. This can happen when
 /// creating a typedef with a lower alignment than the original type and then
@@ -5725,6 +5770,12 @@ void Sema::checkCall(NamedDecl *FDecl, const FunctionProtoType *Proto,
         if (Arg->containsErrors())
           continue;
 
+        if (Context.getTargetInfo().getTriple().isOSAIX() && FDecl && Arg &&
+            FDecl->hasLinkage() &&
+            FDecl->getFormalLinkage() != InternalLinkage &&
+            CallType == VariadicDoesNotApply)
+          checkAIXMemberAlignment((Arg->getExprLoc()), Arg);
+
         QualType ParamTy = Proto->getParamType(ArgIdx);
         QualType ArgTy = Arg->getType();
         CheckArgAlignment(Arg->getExprLoc(), FDecl, std::to_string(ArgIdx + 1),
@@ -7695,7 +7746,7 @@ bool Sema::SemaBuiltinOSLogFormat(CallExpr *TheCall) {
     llvm::SmallBitVector CheckedVarArgs(NumArgs, false);
     ArrayRef<const Expr *> Args(TheCall->getArgs(), TheCall->getNumArgs());
     bool Success = CheckFormatArguments(
-        Args, /*HasVAListArg*/ false, FormatIdx, FirstDataArg, FST_OSLog,
+        Args, FAPK_Variadic, FormatIdx, FirstDataArg, FST_OSLog,
         VariadicFunction, TheCall->getBeginLoc(), SourceRange(),
         CheckedVarArgs);
     if (!Success)
@@ -8412,19 +8463,15 @@ class FormatStringLiteral {
   SourceLocation getEndLoc() const LLVM_READONLY { return FExpr->getEndLoc(); }
 };
 
-}  // namespace
+} // namespace
 
-static void CheckFormatString(Sema &S, const FormatStringLiteral *FExpr,
-                              const Expr *OrigFormatExpr,
-                              ArrayRef<const Expr *> Args,
-                              bool HasVAListArg, unsigned format_idx,
-                              unsigned firstDataArg,
-                              Sema::FormatStringType Type,
-                              bool inFunctionCall,
-                              Sema::VariadicCallType CallType,
-                              llvm::SmallBitVector &CheckedVarArgs,
-                              UncoveredArgHandler &UncoveredArg,
-                              bool IgnoreStringsWithoutSpecifiers);
+static void CheckFormatString(
+    Sema &S, const FormatStringLiteral *FExpr, const Expr *OrigFormatExpr,
+    ArrayRef<const Expr *> Args, Sema::FormatArgumentPassingKind APK,
+    unsigned format_idx, unsigned firstDataArg, Sema::FormatStringType Type,
+    bool inFunctionCall, Sema::VariadicCallType CallType,
+    llvm::SmallBitVector &CheckedVarArgs, UncoveredArgHandler &UncoveredArg,
+    bool IgnoreStringsWithoutSpecifiers);
 
 // Determine if an expression is a string literal or constant string.
 // If this function returns false on the arguments to a function expecting a
@@ -8432,16 +8479,15 @@ static void CheckFormatString(Sema &S, const FormatStringLiteral *FExpr,
 // True string literals are then checked by CheckFormatString.
 static StringLiteralCheckType
 checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
-                      bool HasVAListArg, unsigned format_idx,
+                      Sema::FormatArgumentPassingKind APK, unsigned format_idx,
                       unsigned firstDataArg, Sema::FormatStringType Type,
                       Sema::VariadicCallType CallType, bool InFunctionCall,
                       llvm::SmallBitVector &CheckedVarArgs,
-                      UncoveredArgHandler &UncoveredArg,
-                      llvm::APSInt Offset,
+                      UncoveredArgHandler &UncoveredArg, llvm::APSInt Offset,
                       bool IgnoreStringsWithoutSpecifiers = false) {
   if (S.isConstantEvaluated())
     return SLCT_NotALiteral;
- tryAgain:
+tryAgain:
   assert(Offset.isSigned() && "invalid offset");
 
   if (E->isTypeDependent() || E->isValueDependent())
@@ -8486,9 +8532,8 @@ checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
     if (!CheckLeft)
       Left = SLCT_UncheckedLiteral;
     else {
-      Left = checkFormatStringExpr(S, C->getTrueExpr(), Args,
-                                   HasVAListArg, format_idx, firstDataArg,
-                                   Type, CallType, InFunctionCall,
+      Left = checkFormatStringExpr(S, C->getTrueExpr(), Args, APK, format_idx,
+                                   firstDataArg, Type, CallType, InFunctionCall,
                                    CheckedVarArgs, UncoveredArg, Offset,
                                    IgnoreStringsWithoutSpecifiers);
       if (Left == SLCT_NotALiteral || !CheckRight) {
@@ -8497,8 +8542,8 @@ checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
     }
 
     StringLiteralCheckType Right = checkFormatStringExpr(
-        S, C->getFalseExpr(), Args, HasVAListArg, format_idx, firstDataArg,
-        Type, CallType, InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
+        S, C->getFalseExpr(), Args, APK, format_idx, firstDataArg, Type,
+        CallType, InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
         IgnoreStringsWithoutSpecifiers);
 
     return (CheckLeft && Left < Right) ? Left : Right;
@@ -8548,42 +8593,85 @@ checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
             if (InitList->isStringLiteralInit())
               Init = InitList->getInit(0)->IgnoreParenImpCasts();
           }
-          return checkFormatStringExpr(S, Init, Args,
-                                       HasVAListArg, format_idx,
-                                       firstDataArg, Type, CallType,
-                                       /*InFunctionCall*/ false, CheckedVarArgs,
-                                       UncoveredArg, Offset);
+          return checkFormatStringExpr(
+              S, Init, Args, APK, format_idx, firstDataArg, Type, CallType,
+              /*InFunctionCall*/ false, CheckedVarArgs, UncoveredArg, Offset);
         }
       }
 
-      // For vprintf* functions (i.e., HasVAListArg==true), we add a
-      // special check to see if the format string is a function parameter
-      // of the function calling the printf function.  If the function
-      // has an attribute indicating it is a printf-like function, then we
-      // should suppress warnings concerning non-literals being used in a call
-      // to a vprintf function.  For example:
+      // When the format argument is an argument of this function, and this
+      // function also has the format attribute, there are several interactions
+      // for which there shouldn't be a warning. For instance, when calling
+      // v*printf from a function that has the printf format attribute, we
+      // should not emit a warning about using `fmt`, even though it's not
+      // constant, because the arguments have already been checked for the
+      // caller of `logmessage`:
       //
-      // void
-      // logmessage(char const *fmt __attribute__ (format (printf, 1, 2)), ...){
-      //      va_list ap;
-      //      va_start(ap, fmt);
-      //      vprintf(fmt, ap);  // Do NOT emit a warning about "fmt".
-      //      ...
+      //  __attribute__((format(printf, 1, 2)))
+      //  void logmessage(char const *fmt, ...) {
+      //    va_list ap;
+      //    va_start(ap, fmt);
+      //    vprintf(fmt, ap);  /* do not emit a warning about "fmt" */
+      //    ...
       // }
-      if (HasVAListArg) {
-        if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(VD)) {
-          if (const Decl *D = dyn_cast<Decl>(PV->getDeclContext())) {
-            int PVIndex = PV->getFunctionScopeIndex() + 1;
-            for (const auto *PVFormat : D->specific_attrs<FormatAttr>()) {
-              // adjust for implicit parameter
-              if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D))
-                if (MD->isInstance())
-                  ++PVIndex;
+      //
+      // Another interaction that we need to support is calling a variadic
+      // format function from a format function that has fixed arguments. For
+      // instance:
+      //
+      //  __attribute__((format(printf, 1, 2)))
+      //  void logstring(char const *fmt, char const *str) {
+      //    printf(fmt, str);  /* do not emit a warning about "fmt" */
+      //  }
+      //
+      // Same (and perhaps more relatably) for the variadic template case:
+      //
+      //  template<typename... Args>
+      //  __attribute__((format(printf, 1, 2)))
+      //  void log(const char *fmt, Args&&... args) {
+      //    printf(fmt, forward<Args>(args)...);
+      //           /* do not emit a warning about "fmt" */
+      //  }
+      //
+      // Due to implementation difficulty, we only check the format, not the
+      // format arguments, in all cases.
+      //
+      if (const auto *PV = dyn_cast<ParmVarDecl>(VD)) {
+        if (const auto *D = dyn_cast<Decl>(PV->getDeclContext())) {
+          for (const auto *PVFormat : D->specific_attrs<FormatAttr>()) {
+            bool IsCXXMember = false;
+            if (const auto *MD = dyn_cast<CXXMethodDecl>(D))
+              IsCXXMember = MD->isInstance();
+
+            bool IsVariadic = false;
+            if (const FunctionType *FnTy = D->getFunctionType())
+              IsVariadic = cast<FunctionProtoType>(FnTy)->isVariadic();
+            else if (const auto *BD = dyn_cast<BlockDecl>(D))
+              IsVariadic = BD->isVariadic();
+            else if (const auto *OMD = dyn_cast<ObjCMethodDecl>(D))
+              IsVariadic = OMD->isVariadic();
+
+            Sema::FormatStringInfo CallerFSI;
+            if (Sema::getFormatStringInfo(PVFormat, IsCXXMember, IsVariadic,
+                                          &CallerFSI)) {
               // We also check if the formats are compatible.
               // We can't pass a 'scanf' string to a 'printf' function.
-              if (PVIndex == PVFormat->getFormatIdx() &&
-                  Type == S.GetFormatStringType(PVFormat))
-                return SLCT_UncheckedLiteral;
+              if (PV->getFunctionScopeIndex() == CallerFSI.FormatIdx &&
+                  Type == S.GetFormatStringType(PVFormat)) {
+                // Lastly, check that argument passing kinds transition in a
+                // way that makes sense:
+                // from a caller with FAPK_VAList, allow FAPK_VAList
+                // from a caller with FAPK_Fixed, allow FAPK_Fixed
+                // from a caller with FAPK_Fixed, allow FAPK_Variadic
+                // from a caller with FAPK_Variadic, allow FAPK_VAList
+                switch (combineFAPK(CallerFSI.ArgPassingKind, APK)) {
+                case combineFAPK(Sema::FAPK_VAList, Sema::FAPK_VAList):
+                case combineFAPK(Sema::FAPK_Fixed, Sema::FAPK_Fixed):
+                case combineFAPK(Sema::FAPK_Fixed, Sema::FAPK_Variadic):
+                case combineFAPK(Sema::FAPK_Variadic, Sema::FAPK_VAList):
+                  return SLCT_UncheckedLiteral;
+                }
+              }
             }
           }
         }
@@ -8602,8 +8690,8 @@ checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
       for (const auto *FA : ND->specific_attrs<FormatArgAttr>()) {
         const Expr *Arg = CE->getArg(FA->getFormatIdx().getASTIndex());
         StringLiteralCheckType Result = checkFormatStringExpr(
-            S, Arg, Args, HasVAListArg, format_idx, firstDataArg, Type,
-            CallType, InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
+            S, Arg, Args, APK, format_idx, firstDataArg, Type, CallType,
+            InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
             IgnoreStringsWithoutSpecifiers);
         if (IsFirst) {
           CommonResult = Result;
@@ -8618,12 +8706,10 @@ checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
         if (BuiltinID == Builtin::BI__builtin___CFStringMakeConstantString ||
             BuiltinID == Builtin::BI__builtin___NSStringMakeConstantString) {
           const Expr *Arg = CE->getArg(0);
-          return checkFormatStringExpr(S, Arg, Args,
-                                       HasVAListArg, format_idx,
-                                       firstDataArg, Type, CallType,
-                                       InFunctionCall, CheckedVarArgs,
-                                       UncoveredArg, Offset,
-                                       IgnoreStringsWithoutSpecifiers);
+          return checkFormatStringExpr(
+              S, Arg, Args, APK, format_idx, firstDataArg, Type, CallType,
+              InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
+              IgnoreStringsWithoutSpecifiers);
         }
       }
     }
@@ -8651,8 +8737,8 @@ checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
 
         const Expr *Arg = ME->getArg(FA->getFormatIdx().getASTIndex());
         return checkFormatStringExpr(
-            S, Arg, Args, HasVAListArg, format_idx, firstDataArg, Type,
-            CallType, InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
+            S, Arg, Args, APK, format_idx, firstDataArg, Type, CallType,
+            InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
             IgnoreStringsWithoutSpecifiers);
       }
     }
@@ -8675,9 +8761,8 @@ checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
         return SLCT_NotALiteral;
       }
       FormatStringLiteral FStr(StrE, Offset.sextOrTrunc(64).getSExtValue());
-      CheckFormatString(S, &FStr, E, Args, HasVAListArg, format_idx,
-                        firstDataArg, Type, InFunctionCall, CallType,
-                        CheckedVarArgs, UncoveredArg,
+      CheckFormatString(S, &FStr, E, Args, APK, format_idx, firstDataArg, Type,
+                        InFunctionCall, CallType, CheckedVarArgs, UncoveredArg,
                         IgnoreStringsWithoutSpecifiers);
       return SLCT_CheckedLiteral;
     }
@@ -8756,24 +8841,25 @@ Sema::FormatStringType Sema::GetFormatStringType(const FormatAttr *Format) {
 /// functions) for correct use of format strings.
 /// Returns true if a format string has been fully checked.
 bool Sema::CheckFormatArguments(const FormatAttr *Format,
-                                ArrayRef<const Expr *> Args,
-                                bool IsCXXMember,
-                                VariadicCallType CallType,
-                                SourceLocation Loc, SourceRange Range,
+                                ArrayRef<const Expr *> Args, bool IsCXXMember,
+                                VariadicCallType CallType, SourceLocation Loc,
+                                SourceRange Range,
                                 llvm::SmallBitVector &CheckedVarArgs) {
   FormatStringInfo FSI;
-  if (getFormatStringInfo(Format, IsCXXMember, &FSI))
-    return CheckFormatArguments(Args, FSI.HasVAListArg, FSI.FormatIdx,
+  if (getFormatStringInfo(Format, IsCXXMember, CallType != VariadicDoesNotApply,
+                          &FSI))
+    return CheckFormatArguments(Args, FSI.ArgPassingKind, FSI.FormatIdx,
                                 FSI.FirstDataArg, GetFormatStringType(Format),
                                 CallType, Loc, Range, CheckedVarArgs);
   return false;
 }
 
 bool Sema::CheckFormatArguments(ArrayRef<const Expr *> Args,
-                                bool HasVAListArg, unsigned format_idx,
-                                unsigned firstDataArg, FormatStringType Type,
-                                VariadicCallType CallType,
-                                SourceLocation Loc, SourceRange Range,
+                                Sema::FormatArgumentPassingKind APK,
+                                unsigned format_idx, unsigned firstDataArg,
+                                FormatStringType Type,
+                                VariadicCallType CallType, SourceLocation Loc,
+                                SourceRange Range,
                                 llvm::SmallBitVector &CheckedVarArgs) {
   // CHECK: printf/scanf-like function is called with no format string.
   if (format_idx >= Args.size()) {
@@ -8796,12 +8882,11 @@ bool Sema::CheckFormatArguments(ArrayRef<const Expr *> Args,
   // ObjC string uses the same format specifiers as C string, so we can use
   // the same format string checking logic for both ObjC and C strings.
   UncoveredArgHandler UncoveredArg;
-  StringLiteralCheckType CT =
-      checkFormatStringExpr(*this, OrigFormatExpr, Args, HasVAListArg,
-                            format_idx, firstDataArg, Type, CallType,
-                            /*IsFunctionCall*/ true, CheckedVarArgs,
-                            UncoveredArg,
-                            /*no string offset*/ llvm::APSInt(64, false) = 0);
+  StringLiteralCheckType CT = checkFormatStringExpr(
+      *this, OrigFormatExpr, Args, APK, format_idx, firstDataArg, Type,
+      CallType,
+      /*IsFunctionCall*/ true, CheckedVarArgs, UncoveredArg,
+      /*no string offset*/ llvm::APSInt(64, false) = 0);
 
   // Generate a diagnostic where an uncovered argument is detected.
   if (UncoveredArg.hasUncoveredArg()) {
@@ -8864,7 +8949,7 @@ protected:
   const unsigned FirstDataArg;
   const unsigned NumDataArgs;
   const char *Beg; // Start of format string.
-  const bool HasVAListArg;
+  const Sema::FormatArgumentPassingKind ArgPassingKind;
   ArrayRef<const Expr *> Args;
   unsigned FormatIdx;
   llvm::SmallBitVector CoveredArgs;
@@ -8879,14 +8964,15 @@ public:
   CheckFormatHandler(Sema &s, const FormatStringLiteral *fexpr,
                      const Expr *origFormatExpr,
                      const Sema::FormatStringType type, unsigned firstDataArg,
-                     unsigned numDataArgs, const char *beg, bool hasVAListArg,
+                     unsigned numDataArgs, const char *beg,
+                     Sema::FormatArgumentPassingKind APK,
                      ArrayRef<const Expr *> Args, unsigned formatIdx,
                      bool inFunctionCall, Sema::VariadicCallType callType,
                      llvm::SmallBitVector &CheckedVarArgs,
                      UncoveredArgHandler &UncoveredArg)
       : S(s), FExpr(fexpr), OrigFormatExpr(origFormatExpr), FSType(type),
         FirstDataArg(firstDataArg), NumDataArgs(numDataArgs), Beg(beg),
-        HasVAListArg(hasVAListArg), Args(Args), FormatIdx(formatIdx),
+        ArgPassingKind(APK), Args(Args), FormatIdx(formatIdx),
         inFunctionCall(inFunctionCall), CallType(callType),
         CheckedVarArgs(CheckedVarArgs), UncoveredArg(UncoveredArg) {
     CoveredArgs.resize(numDataArgs);
@@ -9122,8 +9208,8 @@ const Expr *CheckFormatHandler::getDataArg(unsigned i) const {
 void CheckFormatHandler::DoneProcessing() {
   // Does the number of data arguments exceed the number of
   // format conversions in the format string?
-  if (!HasVAListArg) {
-      // Find any arguments that weren't covered.
+  if (ArgPassingKind != Sema::FAPK_VAList) {
+    // Find any arguments that weren't covered.
     CoveredArgs.flip();
     signed notCoveredArg = CoveredArgs.find_first();
     if (notCoveredArg >= 0) {
@@ -9318,13 +9404,13 @@ public:
                      const Expr *origFormatExpr,
                      const Sema::FormatStringType type, unsigned firstDataArg,
                      unsigned numDataArgs, bool isObjC, const char *beg,
-                     bool hasVAListArg, ArrayRef<const Expr *> Args,
-                     unsigned formatIdx, bool inFunctionCall,
-                     Sema::VariadicCallType CallType,
+                     Sema::FormatArgumentPassingKind APK,
+                     ArrayRef<const Expr *> Args, unsigned formatIdx,
+                     bool inFunctionCall, Sema::VariadicCallType CallType,
                      llvm::SmallBitVector &CheckedVarArgs,
                      UncoveredArgHandler &UncoveredArg)
       : CheckFormatHandler(s, fexpr, origFormatExpr, type, firstDataArg,
-                           numDataArgs, beg, hasVAListArg, Args, formatIdx,
+                           numDataArgs, beg, APK, Args, formatIdx,
                            inFunctionCall, CallType, CheckedVarArgs,
                            UncoveredArg) {}
 
@@ -9399,17 +9485,16 @@ void CheckPrintfHandler::handleInvalidMaskType(StringRef MaskType) {
 }
 
 bool CheckPrintfHandler::HandleAmount(
-                               const analyze_format_string::OptionalAmount &Amt,
-                               unsigned k, const char *startSpecifier,
-                               unsigned specifierLen) {
+    const analyze_format_string::OptionalAmount &Amt, unsigned k,
+    const char *startSpecifier, unsigned specifierLen) {
   if (Amt.hasDataArgument()) {
-    if (!HasVAListArg) {
+    if (ArgPassingKind != Sema::FAPK_VAList) {
       unsigned argIndex = Amt.getArgIndex();
       if (argIndex >= NumDataArgs) {
         EmitFormatDiagnostic(S.PDiag(diag::warn_printf_asterisk_missing_arg)
-                               << k,
+                                 << k,
                              getLocationOfByte(Amt.getStart()),
-                             /*IsStringLocation*/true,
+                             /*IsStringLocation*/ true,
                              getSpecifierRange(startSpecifier, specifierLen));
         // Don't do any more checking.  We will just emit
         // spurious errors.
@@ -9805,7 +9890,7 @@ bool CheckPrintfHandler::HandlePrintfSpecifier(
     HandleNonStandardConversionSpecifier(CS, startSpecifier, specifierLen);
 
   // The remaining checks depend on the data arguments.
-  if (HasVAListArg)
+  if (ArgPassingKind == Sema::FAPK_VAList)
     return true;
 
   if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex))
@@ -9953,6 +10038,12 @@ CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
     ExprTy = TET->getUnderlyingExpr()->getType();
   }
 
+  // When using the format attribute in C++, you can receive a function or an
+  // array that will necessarily decay to a pointer when passed to the final
+  // format consumer. Apply decay before type comparison.
+  if (ExprTy->canDecayToPointerType())
+    ExprTy = S.Context.getDecayedType(ExprTy);
+
   // Diagnose attempts to print a boolean value as a character. Unlike other
   // -Wformat diagnostics, this is fine from a type perspective, but it still
   // doesn't make sense.
@@ -10173,6 +10264,7 @@ CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
     // Since the warning for passing non-POD types to variadic functions
     // was deferred until now, we emit a warning for non-POD
     // arguments here.
+    bool EmitTypeMismatch = false;
     switch (S.isValidVarArgType(ExprTy)) {
     case Sema::VAK_Valid:
     case Sema::VAK_ValidInCXX11: {
@@ -10198,17 +10290,23 @@ CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
     }
     case Sema::VAK_Undefined:
     case Sema::VAK_MSVCUndefined:
-      EmitFormatDiagnostic(S.PDiag(diag::warn_non_pod_vararg_with_format_string)
-                               << S.getLangOpts().CPlusPlus11 << ExprTy
-                               << CallType
-                               << AT.getRepresentativeTypeName(S.Context) << CSR
-                               << E->getSourceRange(),
-                           E->getBeginLoc(), /*IsStringLocation*/ false, CSR);
-      checkForCStrMembers(AT, E);
+      if (CallType == Sema::VariadicDoesNotApply) {
+        EmitTypeMismatch = true;
+      } else {
+        EmitFormatDiagnostic(
+            S.PDiag(diag::warn_non_pod_vararg_with_format_string)
+                << S.getLangOpts().CPlusPlus11 << ExprTy << CallType
+                << AT.getRepresentativeTypeName(S.Context) << CSR
+                << E->getSourceRange(),
+            E->getBeginLoc(), /*IsStringLocation*/ false, CSR);
+        checkForCStrMembers(AT, E);
+      }
       break;
 
     case Sema::VAK_Invalid:
-      if (ExprTy->isObjCObjectType())
+      if (CallType == Sema::VariadicDoesNotApply)
+        EmitTypeMismatch = true;
+      else if (ExprTy->isObjCObjectType())
         EmitFormatDiagnostic(
             S.PDiag(diag::err_cannot_pass_objc_interface_to_vararg_format)
                 << S.getLangOpts().CPlusPlus11 << ExprTy << CallType
@@ -10224,6 +10322,19 @@ CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
       break;
     }
 
+    if (EmitTypeMismatch) {
+      // The function is not variadic, so we do not generate warnings about
+      // being allowed to pass that object as a variadic argument. Instead,
+      // since there are inherently no printf specifiers for types which cannot
+      // be passed as variadic arguments, emit a plain old specifier mismatch
+      // argument.
+      EmitFormatDiagnostic(
+          S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
+              << AT.getRepresentativeTypeName(S.Context) << ExprTy << false
+              << E->getSourceRange(),
+          E->getBeginLoc(), false, CSR);
+    }
+
     assert(FirstDataArg + FS.getArgIndex() < CheckedVarArgs.size() &&
            "format string specifier index out of range");
     CheckedVarArgs[FirstDataArg + FS.getArgIndex()] = true;
@@ -10241,13 +10352,13 @@ public:
   CheckScanfHandler(Sema &s, const FormatStringLiteral *fexpr,
                     const Expr *origFormatExpr, Sema::FormatStringType type,
                     unsigned firstDataArg, unsigned numDataArgs,
-                    const char *beg, bool hasVAListArg,
+                    const char *beg, Sema::FormatArgumentPassingKind APK,
                     ArrayRef<const Expr *> Args, unsigned formatIdx,
                     bool inFunctionCall, Sema::VariadicCallType CallType,
                     llvm::SmallBitVector &CheckedVarArgs,
                     UncoveredArgHandler &UncoveredArg)
       : CheckFormatHandler(s, fexpr, origFormatExpr, type, firstDataArg,
-                           numDataArgs, beg, hasVAListArg, Args, formatIdx,
+                           numDataArgs, beg, APK, Args, formatIdx,
                            inFunctionCall, CallType, CheckedVarArgs,
                            UncoveredArg) {}
 
@@ -10351,7 +10462,7 @@ bool CheckScanfHandler::HandleScanfSpecifier(
     HandleNonStandardConversionSpecifier(CS, startSpecifier, specifierLen);
 
   // The remaining checks depend on the data arguments.
-  if (HasVAListArg)
+  if (ArgPassingKind == Sema::FAPK_VAList)
     return true;
 
   if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex))
@@ -10408,17 +10519,13 @@ bool CheckScanfHandler::HandleScanfSpecifier(
   return true;
 }
 
-static void CheckFormatString(Sema &S, const FormatStringLiteral *FExpr,
-                              const Expr *OrigFormatExpr,
-                              ArrayRef<const Expr *> Args,
-                              bool HasVAListArg, unsigned format_idx,
-                              unsigned firstDataArg,
-                              Sema::FormatStringType Type,
-                              bool inFunctionCall,
-                              Sema::VariadicCallType CallType,
-                              llvm::SmallBitVector &CheckedVarArgs,
-                              UncoveredArgHandler &UncoveredArg,
-                              bool IgnoreStringsWithoutSpecifiers) {
+static void CheckFormatString(
+    Sema &S, const FormatStringLiteral *FExpr, const Expr *OrigFormatExpr,
+    ArrayRef<const Expr *> Args, Sema::FormatArgumentPassingKind APK,
+    unsigned format_idx, unsigned firstDataArg, Sema::FormatStringType Type,
+    bool inFunctionCall, Sema::VariadicCallType CallType,
+    llvm::SmallBitVector &CheckedVarArgs, UncoveredArgHandler &UncoveredArg,
+    bool IgnoreStringsWithoutSpecifiers) {
   // CHECK: is the format string a wide literal?
   if (!FExpr->isAscii() && !FExpr->isUTF8()) {
     CheckFormatHandler::EmitFormatDiagnostic(
@@ -10469,23 +10576,21 @@ static void CheckFormatString(Sema &S, const FormatStringLiteral *FExpr,
       Type == Sema::FST_OSTrace) {
     CheckPrintfHandler H(
         S, FExpr, OrigFormatExpr, Type, firstDataArg, numDataArgs,
-        (Type == Sema::FST_NSString || Type == Sema::FST_OSTrace), Str,
-        HasVAListArg, Args, format_idx, inFunctionCall, CallType,
-        CheckedVarArgs, UncoveredArg);
-
-    if (!analyze_format_string::ParsePrintfString(H, Str, Str + StrLen,
-                                                  S.getLangOpts(),
-                                                  S.Context.getTargetInfo(),
-                                            Type == Sema::FST_FreeBSDKPrintf))
+        (Type == Sema::FST_NSString || Type == Sema::FST_OSTrace), Str, APK,
+        Args, format_idx, inFunctionCall, CallType, CheckedVarArgs,
+        UncoveredArg);
+
+    if (!analyze_format_string::ParsePrintfString(
+            H, Str, Str + StrLen, S.getLangOpts(), S.Context.getTargetInfo(),
+            Type == Sema::FST_FreeBSDKPrintf))
       H.DoneProcessing();
   } else if (Type == Sema::FST_Scanf) {
     CheckScanfHandler H(S, FExpr, OrigFormatExpr, Type, firstDataArg,
-                        numDataArgs, Str, HasVAListArg, Args, format_idx,
-                        inFunctionCall, CallType, CheckedVarArgs, UncoveredArg);
+                        numDataArgs, Str, APK, Args, format_idx, inFunctionCall,
+                        CallType, CheckedVarArgs, UncoveredArg);
 
-    if (!analyze_format_string::ParseScanfString(H, Str, Str + StrLen,
-                                                 S.getLangOpts(),
-                                                 S.Context.getTargetInfo()))
+    if (!analyze_format_string::ParseScanfString(
+            H, Str, Str + StrLen, S.getLangOpts(), S.Context.getTargetInfo()))
       H.DoneProcessing();
   } // TODO: handle other formats
 }
@@ -16765,9 +16870,15 @@ void Sema::DiagnoseSelfMove(const Expr *LHSExpr, const Expr *RHSExpr,
         RHSDeclRef->getDecl()->getCanonicalDecl())
       return;
 
-    Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
-                                        << LHSExpr->getSourceRange()
-                                        << RHSExpr->getSourceRange();
+    auto D = Diag(OpLoc, diag::warn_self_move)
+             << LHSExpr->getType() << LHSExpr->getSourceRange()
+             << RHSExpr->getSourceRange();
+    if (const FieldDecl *F =
+            getSelfAssignmentClassMemberCandidate(RHSDeclRef->getDecl()))
+      D << 1 << F
+        << FixItHint::CreateInsertion(LHSDeclRef->getBeginLoc(), "this->");
+    else
+      D << 0;
     return;
   }
 
@@ -16802,16 +16913,16 @@ void Sema::DiagnoseSelfMove(const Expr *LHSExpr, const Expr *RHSExpr,
         RHSDeclRef->getDecl()->getCanonicalDecl())
       return;
 
-    Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
-                                        << LHSExpr->getSourceRange()
-                                        << RHSExpr->getSourceRange();
+    Diag(OpLoc, diag::warn_self_move)
+        << LHSExpr->getType() << 0 << LHSExpr->getSourceRange()
+        << RHSExpr->getSourceRange();
     return;
   }
 
   if (isa<CXXThisExpr>(LHSBase) && isa<CXXThisExpr>(RHSBase))
-    Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
-                                        << LHSExpr->getSourceRange()
-                                        << RHSExpr->getSourceRange();
+    Diag(OpLoc, diag::warn_self_move)
+        << LHSExpr->getType() << 0 << LHSExpr->getSourceRange()
+        << RHSExpr->getSourceRange();
 }
 
 //===--- Layout compatibility ----------------------------------------------//
diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index 8c9ed5389488..86bad736227d 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -5362,8 +5362,8 @@ private:
       // Overwrite existing if the new member has more info.
       // The preference of . vs :: vs -> is fairly arbitrary.
       if (/*Inserted*/ R.second ||
-          std::make_tuple(M.ArgTypes.hasValue(), M.ResultType != nullptr,
-                          M.Operator) > std::make_tuple(O.ArgTypes.hasValue(),
+          std::make_tuple(M.ArgTypes.has_value(), M.ResultType != nullptr,
+                          M.Operator) > std::make_tuple(O.ArgTypes.has_value(),
                                                         O.ResultType != nullptr,
                                                         O.Operator))
         O = std::move(M);
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 1139088ecde2..5a546503cced 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -1625,22 +1625,20 @@ bool Sema::CheckRedeclarationModuleOwnership(NamedDecl *New, NamedDecl *Old) {
   Module *NewM = New->getOwningModule();
   Module *OldM = Old->getOwningModule();
 
-  if (NewM && NewM->Kind == Module::PrivateModuleFragment)
+  if (NewM && NewM->isPrivateModule())
     NewM = NewM->Parent;
-  if (OldM && OldM->Kind == Module::PrivateModuleFragment)
+  if (OldM && OldM->isPrivateModule())
     OldM = OldM->Parent;
 
-  // If we have a decl in a module partition, it is part of the containing
-  // module (which is the only thing that can be importing it).
-  if (NewM && OldM &&
-      (OldM->Kind == Module::ModulePartitionInterface ||
-       OldM->Kind == Module::ModulePartitionImplementation)) {
-    return false;
-  }
-
   if (NewM == OldM)
     return false;
 
+  // Partitions are part of the module, but a partition could import another
+  // module, so verify that the PMIs agree.
+  if (NewM && OldM && (NewM->isModulePartition() || OldM->isModulePartition()))
+    return NewM->getPrimaryModuleInterfaceName() ==
+           OldM->getPrimaryModuleInterfaceName();
+
   bool NewIsModuleInterface = NewM && NewM->isModulePurview();
   bool OldIsModuleInterface = OldM && OldM->isModulePurview();
   if (NewIsModuleInterface || OldIsModuleInterface) {
@@ -3209,6 +3207,45 @@ static void mergeParamDeclAttributes(ParmVarDecl *newDecl,
   if (!foundAny) newDecl->dropAttrs();
 }
 
+static bool EquivalentArrayTypes(QualType Old, QualType New,
+                                 const ASTContext &Ctx) {
+
+  auto NoSizeInfo = [&Ctx](QualType Ty) {
+    if (Ty->isIncompleteArrayType() || Ty->isPointerType())
+      return true;
+    if (const auto *VAT = Ctx.getAsVariableArrayType(Ty))
+      return VAT->getSizeModifier() == ArrayType::ArraySizeModifier::Star;
+    return false;
+  };
+
+  // `type[]` is equivalent to `type *` and `type[*]`.
+  if (NoSizeInfo(Old) && NoSizeInfo(New))
+    return true;
+
+  // Don't try to compare VLA sizes, unless one of them has the star modifier.
+  if (Old->isVariableArrayType() && New->isVariableArrayType()) {
+    const auto *OldVAT = Ctx.getAsVariableArrayType(Old);
+    const auto *NewVAT = Ctx.getAsVariableArrayType(New);
+    if ((OldVAT->getSizeModifier() == ArrayType::ArraySizeModifier::Star) ^
+        (NewVAT->getSizeModifier() == ArrayType::ArraySizeModifier::Star))
+      return false;
+    return true;
+  }
+
+  // Only compare size, ignore Size modifiers and CVR.
+  if (Old->isConstantArrayType() && New->isConstantArrayType()) {
+    return Ctx.getAsConstantArrayType(Old)->getSize() ==
+           Ctx.getAsConstantArrayType(New)->getSize();
+  }
+
+  // Don't try to compare dependent sized array
+  if (Old->isDependentSizedArrayType() && New->isDependentSizedArrayType()) {
+    return true;
+  }
+
+  return Old == New;
+}
+
 static void mergeParamDeclTypes(ParmVarDecl *NewParam,
                                 const ParmVarDecl *OldParam,
                                 Sema &S) {
@@ -3234,6 +3271,19 @@ static void mergeParamDeclTypes(ParmVarDecl *NewParam,
       NewParam->setType(NewT);
     }
   }
+  const auto *OldParamDT = dyn_cast<DecayedType>(OldParam->getType());
+  const auto *NewParamDT = dyn_cast<DecayedType>(NewParam->getType());
+  if (OldParamDT && NewParamDT &&
+      OldParamDT->getPointeeType() == NewParamDT->getPointeeType()) {
+    QualType OldParamOT = OldParamDT->getOriginalType();
+    QualType NewParamOT = NewParamDT->getOriginalType();
+    if (!EquivalentArrayTypes(OldParamOT, NewParamOT, S.getASTContext())) {
+      S.Diag(NewParam->getLocation(), diag::warn_inconsistent_array_form)
+          << NewParam << NewParamOT;
+      S.Diag(OldParam->getLocation(), diag::note_previous_declaration_as)
+          << OldParamOT;
+    }
+  }
 }
 
 namespace {
@@ -15464,7 +15514,7 @@ void Sema::AddKnownFunctionAttributesForReplaceableGlobalAllocationFunction(
   //         specified by the value of this argument.
   if (AlignmentParam && !FD->hasAttr<AllocAlignAttr>()) {
     FD->addAttr(AllocAlignAttr::CreateImplicit(
-        Context, ParamIdx(AlignmentParam.getValue(), FD), FD->getLocation()));
+        Context, ParamIdx(AlignmentParam.value(), FD), FD->getLocation()));
   }
 
   // FIXME:
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index f79523983ed8..838fd48357fb 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -2673,7 +2673,7 @@ static void handleAvailabilityAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
         if (IOSToWatchOSMapping) {
           if (auto MappedVersion = IOSToWatchOSMapping->map(
                   Version, MinimumWatchOSVersion, None)) {
-            return MappedVersion.getValue();
+            return MappedVersion.value();
           }
         }
 
@@ -2682,10 +2682,10 @@ static void handleAvailabilityAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
         if (NewMajor >= 2) {
           if (Version.getMinor()) {
             if (Version.getSubminor())
-              return VersionTuple(NewMajor, Version.getMinor().getValue(),
-                                  Version.getSubminor().getValue());
+              return VersionTuple(NewMajor, Version.getMinor().value(),
+                                  Version.getSubminor().value());
             else
-              return VersionTuple(NewMajor, Version.getMinor().getValue());
+              return VersionTuple(NewMajor, Version.getMinor().value());
           }
           return VersionTuple(NewMajor);
         }
@@ -3886,12 +3886,10 @@ static void handleFormatAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
 
   // check if the function is variadic if the 3rd argument non-zero
   if (FirstArg != 0) {
-    if (isFunctionOrMethodVariadic(D)) {
+    if (isFunctionOrMethodVariadic(D))
       ++NumArgs; // +1 for ...
-    } else {
-      S.Diag(D->getLocation(), diag::err_format_attribute_requires_variadic);
-      return;
-    }
+    else
+      S.Diag(D->getLocation(), diag::warn_gcc_requires_variadic_function) << AL;
   }
 
   // strftime requires FirstArg to be 0 because it doesn't read from any
@@ -4314,13 +4312,6 @@ void Sema::AddAlignedAttr(Decl *D, const AttributeCommonInfo &CI, Expr *E,
     return;
 
   uint64_t AlignVal = Alignment.getZExtValue();
-  // 16 byte ByVal alignment not due to a vector member is not honoured by XL
-  // on AIX. Emit a warning here that users are generating binary incompatible
-  // code to be safe.
-  if (AlignVal >= 16 && isa<FieldDecl>(D) &&
-      Context.getTargetInfo().getTriple().isOSAIX())
-    Diag(AttrLoc, diag::warn_not_xl_compatible) << E->getSourceRange();
-
   // C++11 [dcl.align]p2:
   //   -- if the constant expression evaluates to zero, the alignment
   //      specifier shall have no effect
@@ -8002,6 +7993,26 @@ static void handleZeroCallUsedRegsAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   D->addAttr(ZeroCallUsedRegsAttr::Create(S.Context, Kind, AL));
 }
 
+static void handleFunctionReturnThunksAttr(Sema &S, Decl *D,
+                                           const ParsedAttr &AL) {
+  StringRef KindStr;
+  SourceLocation LiteralLoc;
+  if (!S.checkStringLiteralArgumentAttr(AL, 0, KindStr, &LiteralLoc))
+    return;
+
+  FunctionReturnThunksAttr::Kind Kind;
+  if (!FunctionReturnThunksAttr::ConvertStrToKind(KindStr, Kind)) {
+    S.Diag(LiteralLoc, diag::warn_attribute_type_not_supported)
+        << AL << KindStr;
+    return;
+  }
+  // FIXME: it would be good to better handle attribute merging rather than
+  // silently replacing the existing attribute, so long as it does not break
+  // the expected codegen tests.
+  D->dropAttr<FunctionReturnThunksAttr>();
+  D->addAttr(FunctionReturnThunksAttr::Create(S.Context, Kind, AL));
+}
+
 static void handleSYCLKernelAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   // The 'sycl_kernel' attribute applies only to function templates.
   const auto *FD = cast<FunctionDecl>(D);
@@ -8868,6 +8879,9 @@ ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D, const ParsedAttr &AL,
   case ParsedAttr::AT_ZeroCallUsedRegs:
     handleZeroCallUsedRegsAttr(S, D, AL);
     break;
+  case ParsedAttr::AT_FunctionReturnThunks:
+    handleFunctionReturnThunksAttr(S, D, AL);
+    break;
 
   // Microsoft attributes:
   case ParsedAttr::AT_LayoutVersion:
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index b9ecde6f20a0..742c4828b8dc 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -14600,6 +14600,40 @@ static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode(
   return Opc;
 }
 
+const FieldDecl *
+Sema::getSelfAssignmentClassMemberCandidate(const ValueDecl *SelfAssigned) {
+  // Explore the case for adding 'this->' to the LHS of a self assignment, very
+  // common for setters.
+  // struct A {
+  // int X;
+  // -void setX(int X) { X = X; }
+  // +void setX(int X) { this->X = X; }
+  // };
+
+  // Only consider parameters for self assignment fixes.
+  if (!isa<ParmVarDecl>(SelfAssigned))
+    return nullptr;
+  const auto *Method =
+      dyn_cast_or_null<CXXMethodDecl>(getCurFunctionDecl(true));
+  if (!Method)
+    return nullptr;
+
+  const CXXRecordDecl *Parent = Method->getParent();
+  // In theory this is fixable if the lambda explicitly captures this, but
+  // that's added complexity that's rarely going to be used.
+  if (Parent->isLambda())
+    return nullptr;
+
+  // FIXME: Use an actual Lookup operation instead of just traversing fields
+  // in order to get base class fields.
+  auto Field =
+      llvm::find_if(Parent->fields(),
+                    [Name(SelfAssigned->getDeclName())](const FieldDecl *F) {
+                      return F->getDeclName() == Name;
+                    });
+  return (Field != Parent->field_end()) ? *Field : nullptr;
+}
+
 /// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself.
 /// This warning suppressed in the event of macro expansions.
 static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr,
@@ -14630,10 +14664,16 @@ static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr,
     if (RefTy->getPointeeType().isVolatileQualified())
       return;
 
-  S.Diag(OpLoc, IsBuiltin ? diag::warn_self_assignment_builtin
-                          : diag::warn_self_assignment_overloaded)
-      << LHSDeclRef->getType() << LHSExpr->getSourceRange()
-      << RHSExpr->getSourceRange();
+  auto Diag = S.Diag(OpLoc, IsBuiltin ? diag::warn_self_assignment_builtin
+                                      : diag::warn_self_assignment_overloaded)
+              << LHSDeclRef->getType() << LHSExpr->getSourceRange()
+              << RHSExpr->getSourceRange();
+  if (const FieldDecl *SelfAssignField =
+          S.getSelfAssignmentClassMemberCandidate(RHSDecl))
+    Diag << 1 << SelfAssignField
+         << FixItHint::CreateInsertion(LHSDeclRef->getBeginLoc(), "this->");
+  else
+    Diag << 0;
 }
 
 /// Check if a bitwise-& is performed on an Objective-C pointer.  This
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 0d73fcf8bf4e..11f33c7c6363 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -5394,6 +5394,39 @@ static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
   return false;
 }
 
+namespace {
+void DiagnoseBuiltinDeprecation(Sema& S, TypeTrait Kind,
+                                SourceLocation KWLoc) {
+  TypeTrait Replacement;
+  switch (Kind) {
+    case UTT_HasNothrowAssign:
+    case UTT_HasNothrowMoveAssign:
+      Replacement = BTT_IsNothrowAssignable;
+      break;
+    case UTT_HasNothrowCopy:
+    case UTT_HasNothrowConstructor:
+      Replacement = TT_IsNothrowConstructible;
+      break;
+    case UTT_HasTrivialAssign:
+    case UTT_HasTrivialMoveAssign:
+      Replacement = BTT_IsTriviallyAssignable;
+      break;
+    case UTT_HasTrivialCopy:
+    case UTT_HasTrivialDefaultConstructor:
+    case UTT_HasTrivialMoveConstructor:
+      Replacement = TT_IsTriviallyConstructible;
+      break;
+    case UTT_HasTrivialDestructor:
+      Replacement = UTT_IsTriviallyDestructible;
+      break;
+    default:
+      return;
+  }
+  S.Diag(KWLoc, diag::warn_deprecated_builtin)
+    << getTraitSpelling(Kind) << getTraitSpelling(Replacement);
+}
+}
+
 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
                                 ArrayRef<TypeSourceInfo *> Args,
                                 SourceLocation RParenLoc) {
@@ -5403,6 +5436,8 @@ ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
                                *this, Kind, KWLoc, Args[0]->getType()))
     return ExprError();
 
+  DiagnoseBuiltinDeprecation(*this, Kind, KWLoc);
+
   bool Dependent = false;
   for (unsigned I = 0, N = Args.size(); I != N; ++I) {
     if (Args[I]->getType()->isDependentType()) {
diff --git a/clang/lib/Sema/SemaModule.cpp b/clang/lib/Sema/SemaModule.cpp
index 3aa124d457b0..e9a1ac17ce86 100644
--- a/clang/lib/Sema/SemaModule.cpp
+++ b/clang/lib/Sema/SemaModule.cpp
@@ -935,3 +935,16 @@ void Sema::PopGlobalModuleFragment() {
          "left the wrong module scope, which is not global module fragment");
   ModuleScopes.pop_back();
 }
+
+bool Sema::isModuleUnitOfCurrentTU(const Module *M) const {
+  assert(M);
+
+  Module *CurrentModuleUnit = getCurrentModule();
+
+  // If we are not in a module currently, M must not be the module unit of
+  // current TU.
+  if (!CurrentModuleUnit)
+    return false;
+
+  return M->isSubModuleOf(CurrentModuleUnit->getTopLevelModule());
+}
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index 6f501965552e..dc1470bf7a9d 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -840,21 +840,21 @@ public:
   /// false - otherwise.
   bool isOrderedRegion() const {
     if (const SharingMapTy *Top = getTopOfStackOrNull())
-      return Top->OrderedRegion.hasValue();
+      return Top->OrderedRegion.has_value();
     return false;
   }
   /// Returns optional parameter for the ordered region.
   std::pair<const Expr *, OMPOrderedClause *> getOrderedRegionParam() const {
     if (const SharingMapTy *Top = getTopOfStackOrNull())
       if (Top->OrderedRegion)
-        return Top->OrderedRegion.getValue();
+        return Top->OrderedRegion.value();
     return std::make_pair(nullptr, nullptr);
   }
   /// Returns true, if parent region is ordered (has associated
   /// 'ordered' clause), false - otherwise.
   bool isParentOrderedRegion() const {
     if (const SharingMapTy *Parent = getSecondOnStackOrNull())
-      return Parent->OrderedRegion.hasValue();
+      return Parent->OrderedRegion.has_value();
     return false;
   }
   /// Returns optional parameter for the ordered region.
@@ -862,7 +862,7 @@ public:
   getParentOrderedRegionParam() const {
     if (const SharingMapTy *Parent = getSecondOnStackOrNull())
       if (Parent->OrderedRegion)
-        return Parent->OrderedRegion.getValue();
+        return Parent->OrderedRegion.value();
     return std::make_pair(nullptr, nullptr);
   }
   /// Marks current region as nowait (it has a 'nowait' clause).
@@ -7831,9 +7831,9 @@ public:
   /// Return true if any expression is dependent.
   bool dependent() const;
   /// Returns true if the initializer forms non-rectangular loop.
-  bool doesInitDependOnLC() const { return InitDependOnLC.hasValue(); }
+  bool doesInitDependOnLC() const { return InitDependOnLC.has_value(); }
   /// Returns true if the condition forms non-rectangular loop.
-  bool doesCondDependOnLC() const { return CondDependOnLC.hasValue(); }
+  bool doesCondDependOnLC() const { return CondDependOnLC.has_value(); }
   /// Returns index of the loop we depend on (starting from 1), or 0 otherwise.
   unsigned getLoopDependentIdx() const {
     return InitDependOnLC.value_or(CondDependOnLC.value_or(0));
@@ -7942,18 +7942,18 @@ bool OpenMPIterationSpaceChecker::setStep(Expr *NewStep, bool Subtract) {
     if (!TestIsLessOp)
       TestIsLessOp = IsConstPos || (IsUnsigned && !Subtract);
     if (UB &&
-        (IsConstZero || (TestIsLessOp.getValue()
-                             ? (IsConstNeg || (IsUnsigned && Subtract))
-                             : (IsConstPos || (IsUnsigned && !Subtract))))) {
+        (IsConstZero ||
+         (TestIsLessOp.value() ? (IsConstNeg || (IsUnsigned && Subtract))
+                               : (IsConstPos || (IsUnsigned && !Subtract))))) {
       SemaRef.Diag(NewStep->getExprLoc(),
                    diag::err_omp_loop_incr_not_compatible)
-          << LCDecl << TestIsLessOp.getValue() << NewStep->getSourceRange();
+          << LCDecl << TestIsLessOp.value() << NewStep->getSourceRange();
       SemaRef.Diag(ConditionLoc,
                    diag::note_omp_loop_cond_requres_compatible_incr)
-          << TestIsLessOp.getValue() << ConditionSrcRange;
+          << TestIsLessOp.value() << ConditionSrcRange;
       return true;
     }
-    if (TestIsLessOp.getValue() == Subtract) {
+    if (TestIsLessOp.value() == Subtract) {
       NewStep =
           SemaRef.CreateBuiltinUnaryOp(NewStep->getExprLoc(), UO_Minus, NewStep)
               .get();
@@ -8708,8 +8708,8 @@ Expr *OpenMPIterationSpaceChecker::buildNumIterations(
       UBVal = MinUB.get();
     }
   }
-  Expr *UBExpr = TestIsLessOp.getValue() ? UBVal : LBVal;
-  Expr *LBExpr = TestIsLessOp.getValue() ? LBVal : UBVal;
+  Expr *UBExpr = TestIsLessOp.value() ? UBVal : LBVal;
+  Expr *LBExpr = TestIsLessOp.value() ? LBVal : UBVal;
   Expr *Upper = tryBuildCapture(SemaRef, UBExpr, Captures).get();
   Expr *Lower = tryBuildCapture(SemaRef, LBExpr, Captures).get();
   if (!Upper || !Lower)
@@ -8772,12 +8772,12 @@ std::pair<Expr *, Expr *> OpenMPIterationSpaceChecker::buildMinMaxValues(
   // init value.
   Expr *MinExpr = nullptr;
   Expr *MaxExpr = nullptr;
-  Expr *LBExpr = TestIsLessOp.getValue() ? LB : UB;
-  Expr *UBExpr = TestIsLessOp.getValue() ? UB : LB;
-  bool LBNonRect = TestIsLessOp.getValue() ? InitDependOnLC.hasValue()
-                                           : CondDependOnLC.hasValue();
-  bool UBNonRect = TestIsLessOp.getValue() ? CondDependOnLC.hasValue()
-                                           : InitDependOnLC.hasValue();
+  Expr *LBExpr = TestIsLessOp.value() ? LB : UB;
+  Expr *UBExpr = TestIsLessOp.value() ? UB : LB;
+  bool LBNonRect = TestIsLessOp.value() ? InitDependOnLC.has_value()
+                                        : CondDependOnLC.has_value();
+  bool UBNonRect = TestIsLessOp.value() ? CondDependOnLC.has_value()
+                                        : InitDependOnLC.has_value();
   Expr *Lower =
       LBNonRect ? LBExpr : tryBuildCapture(SemaRef, LBExpr, Captures).get();
   Expr *Upper =
@@ -8901,8 +8901,8 @@ Expr *OpenMPIterationSpaceChecker::buildPreCond(
 
   ExprResult CondExpr = SemaRef.BuildBinOp(
       S, DefaultLoc,
-      TestIsLessOp.getValue() ? (TestIsStrictOp ? BO_LT : BO_LE)
-                              : (TestIsStrictOp ? BO_GT : BO_GE),
+      TestIsLessOp.value() ? (TestIsStrictOp ? BO_LT : BO_LE)
+                           : (TestIsStrictOp ? BO_GT : BO_GE),
       NewLB.get(), NewUB.get());
   if (CondExpr.isUsable()) {
     if (!SemaRef.Context.hasSameUnqualifiedType(CondExpr.get()->getType(),
@@ -8978,12 +8978,10 @@ Expr *OpenMPIterationSpaceChecker::buildOrderedLoopData(
       !SemaRef.getLangOpts().CPlusPlus)
     return nullptr;
   // Upper - Lower
-  Expr *Upper = TestIsLessOp.getValue()
-                    ? Cnt
-                    : tryBuildCapture(SemaRef, LB, Captures).get();
-  Expr *Lower = TestIsLessOp.getValue()
-                    ? tryBuildCapture(SemaRef, LB, Captures).get()
-                    : Cnt;
+  Expr *Upper =
+      TestIsLessOp.value() ? Cnt : tryBuildCapture(SemaRef, LB, Captures).get();
+  Expr *Lower =
+      TestIsLessOp.value() ? tryBuildCapture(SemaRef, LB, Captures).get() : Cnt;
   if (!Upper || !Lower)
     return nullptr;
 
@@ -11570,7 +11568,7 @@ protected:
   bool checkType(ErrorInfoTy &ErrorInfo) const;
 
   static bool CheckValue(const Expr *E, ErrorInfoTy &ErrorInfo,
-                         bool ShouldBeLValue) {
+                         bool ShouldBeLValue, bool ShouldBeInteger = false) {
     if (ShouldBeLValue && !E->isLValue()) {
       ErrorInfo.Error = ErrorTy::XNotLValue;
       ErrorInfo.ErrorLoc = ErrorInfo.NoteLoc = E->getExprLoc();
@@ -11586,8 +11584,7 @@ protected:
         ErrorInfo.ErrorRange = ErrorInfo.NoteRange = E->getSourceRange();
         return false;
       }
-
-      if (!QTy->isIntegerType()) {
+      if (ShouldBeInteger && !QTy->isIntegerType()) {
         ErrorInfo.Error = ErrorTy::NotInteger;
         ErrorInfo.ErrorLoc = ErrorInfo.NoteLoc = E->getExprLoc();
         ErrorInfo.ErrorRange = ErrorInfo.NoteRange = E->getSourceRange();
@@ -11890,7 +11887,7 @@ bool OpenMPAtomicCompareCaptureChecker::checkType(ErrorInfoTy &ErrorInfo) {
   if (V && !CheckValue(V, ErrorInfo, true))
     return false;
 
-  if (R && !CheckValue(R, ErrorInfo, true))
+  if (R && !CheckValue(R, ErrorInfo, true, true))
     return false;
 
   return true;
@@ -22588,27 +22585,27 @@ void Sema::ActOnOpenMPDeclareTargetName(NamedDecl *ND, SourceLocation Loc,
   auto *VD = cast<ValueDecl>(ND);
   llvm::Optional<OMPDeclareTargetDeclAttr *> ActiveAttr =
       OMPDeclareTargetDeclAttr::getActiveAttr(VD);
-  if (ActiveAttr && ActiveAttr.getValue()->getDevType() != DTCI.DT &&
-      ActiveAttr.getValue()->getLevel() == Level) {
+  if (ActiveAttr && ActiveAttr.value()->getDevType() != DTCI.DT &&
+      ActiveAttr.value()->getLevel() == Level) {
     Diag(Loc, diag::err_omp_device_type_mismatch)
         << OMPDeclareTargetDeclAttr::ConvertDevTypeTyToStr(DTCI.DT)
         << OMPDeclareTargetDeclAttr::ConvertDevTypeTyToStr(
-               ActiveAttr.getValue()->getDevType());
+               ActiveAttr.value()->getDevType());
     return;
   }
-  if (ActiveAttr && ActiveAttr.getValue()->getMapType() != MT &&
-      ActiveAttr.getValue()->getLevel() == Level) {
+  if (ActiveAttr && ActiveAttr.value()->getMapType() != MT &&
+      ActiveAttr.value()->getLevel() == Level) {
     Diag(Loc, diag::err_omp_declare_target_to_and_link) << ND;
     return;
   }
 
-  if (ActiveAttr && ActiveAttr.getValue()->getLevel() == Level)
+  if (ActiveAttr && ActiveAttr.value()->getLevel() == Level)
     return;
 
   Expr *IndirectE = nullptr;
   bool IsIndirect = false;
   if (DTCI.Indirect) {
-    IndirectE = DTCI.Indirect.getValue();
+    IndirectE = DTCI.Indirect.value();
     if (!IndirectE)
       IsIndirect = true;
   }
@@ -22702,13 +22699,13 @@ void Sema::checkDeclIsAllowedInOpenMPTarget(Expr *E, Decl *D,
         llvm::Optional<OMPDeclareTargetDeclAttr *> ActiveAttr =
             OMPDeclareTargetDeclAttr::getActiveAttr(VD);
         unsigned Level = DeclareTargetNesting.size();
-        if (ActiveAttr && ActiveAttr.getValue()->getLevel() >= Level)
+        if (ActiveAttr && ActiveAttr.value()->getLevel() >= Level)
           return;
         DeclareTargetContextInfo &DTCI = DeclareTargetNesting.back();
         Expr *IndirectE = nullptr;
         bool IsIndirect = false;
         if (DTCI.Indirect) {
-          IndirectE = DTCI.Indirect.getValue();
+          IndirectE = DTCI.Indirect.value();
           if (!IndirectE)
             IsIndirect = true;
         }
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index dbfe6164bda2..67cf8f0371c5 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -2695,8 +2695,15 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
   for (TemplateParameterList::iterator NewParam = NewParams->begin(),
                                     NewParamEnd = NewParams->end();
        NewParam != NewParamEnd; ++NewParam) {
-    // Variables used to diagnose redundant default arguments
+    // Whether we've seen a duplicate default argument in the same translation
+    // unit.
     bool RedundantDefaultArg = false;
+    // Whether we've found inconsis inconsitent default arguments in different
+    // translation unit.
+    bool InconsistentDefaultArg = false;
+    // The name of the module which contains the inconsistent default argument.
+    std::string PrevModuleName;
+
     SourceLocation OldDefaultLoc;
     SourceLocation NewDefaultLoc;
 
@@ -2729,7 +2736,16 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
         OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc();
         NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc();
         SawDefaultArgument = true;
-        RedundantDefaultArg = true;
+
+        if (!OldTypeParm->getOwningModule() ||
+            isModuleUnitOfCurrentTU(OldTypeParm->getOwningModule()))
+          RedundantDefaultArg = true;
+        else if (!getASTContext().isSameDefaultTemplateArgument(OldTypeParm,
+                                                                NewTypeParm)) {
+          InconsistentDefaultArg = true;
+          PrevModuleName =
+              OldTypeParm->getImportedOwningModule()->getFullModuleName();
+        }
         PreviousDefaultArgLoc = NewDefaultLoc;
       } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) {
         // Merge the default argument from the old declaration to the
@@ -2774,7 +2790,15 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
         OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc();
         NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc();
         SawDefaultArgument = true;
-        RedundantDefaultArg = true;
+        if (!OldNonTypeParm->getOwningModule() ||
+            isModuleUnitOfCurrentTU(OldNonTypeParm->getOwningModule()))
+          RedundantDefaultArg = true;
+        else if (!getASTContext().isSameDefaultTemplateArgument(
+                     OldNonTypeParm, NewNonTypeParm)) {
+          InconsistentDefaultArg = true;
+          PrevModuleName =
+              OldNonTypeParm->getImportedOwningModule()->getFullModuleName();
+        }
         PreviousDefaultArgLoc = NewDefaultLoc;
       } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) {
         // Merge the default argument from the old declaration to the
@@ -2818,7 +2842,15 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
         OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation();
         NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation();
         SawDefaultArgument = true;
-        RedundantDefaultArg = true;
+        if (!OldTemplateParm->getOwningModule() ||
+            isModuleUnitOfCurrentTU(OldTemplateParm->getOwningModule()))
+          RedundantDefaultArg = true;
+        else if (!getASTContext().isSameDefaultTemplateArgument(
+                     OldTemplateParm, NewTemplateParm)) {
+          InconsistentDefaultArg = true;
+          PrevModuleName =
+              OldTemplateParm->getImportedOwningModule()->getFullModuleName();
+        }
         PreviousDefaultArgLoc = NewDefaultLoc;
       } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) {
         // Merge the default argument from the old declaration to the
@@ -2845,13 +2877,32 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
       Invalid = true;
     }
 
+    // [basic.def.odr]/13:
+    //     There can be more than one definition of a
+    //     ...
+    //     default template argument
+    //     ...
+    //     in a program provided that each definition appears in a different
+    //     translation unit and the definitions satisfy the [same-meaning
+    //     criteria of the ODR].
+    //
+    // Simply, the design of modules allows the definition of template default
+    // argument to be repeated across translation unit. Note that the ODR is
+    // checked elsewhere. But it is still not allowed to repeat template default
+    // argument in the same translation unit.
     if (RedundantDefaultArg) {
-      // C++ [temp.param]p12:
-      //   A template-parameter shall not be given default arguments
-      //   by two different declarations in the same scope.
       Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition);
       Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg);
       Invalid = true;
+    } else if (InconsistentDefaultArg) {
+      // We could only diagnose about the case that the OldParam is imported.
+      // The case NewParam is imported should be handled in ASTReader.
+      Diag(NewDefaultLoc,
+           diag::err_template_param_default_arg_inconsistent_redefinition);
+      Diag(OldDefaultLoc,
+           diag::note_template_param_prev_default_arg_in_other_module)
+          << PrevModuleName;
+      Invalid = true;
     } else if (MissingDefaultArg && TPC != TPC_FunctionTemplate) {
       // C++ [temp.param]p11:
       //   If a template-parameter of a class template has a default
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index d7558017948a..bd166ff6f594 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -469,8 +469,8 @@ static void instantiateOMPDeclareVariantAttr(
   if (!DeclVarData)
     return;
 
-  E = DeclVarData.getValue().second;
-  FD = DeclVarData.getValue().first;
+  E = DeclVarData.value().second;
+  FD = DeclVarData.value().first;
 
   if (auto *VariantDRE = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts())) {
     if (auto *VariantFD = dyn_cast<FunctionDecl>(VariantDRE->getDecl())) {
@@ -4840,7 +4840,8 @@ void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
                                      /*Complain*/DefinitionRequired)) {
     if (DefinitionRequired)
       Function->setInvalidDecl();
-    else if (TSK == TSK_ExplicitInstantiationDefinition) {
+    else if (TSK == TSK_ExplicitInstantiationDefinition ||
+             (Function->isConstexpr() && !Recursive)) {
       // Try again at the end of the translation unit (at which point a
       // definition will be required).
       assert(!Recursive);
@@ -4855,7 +4856,7 @@ void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
         Diag(PatternDecl->getLocation(), diag::note_forward_template_decl);
         if (getLangOpts().CPlusPlus11)
           Diag(PointOfInstantiation, diag::note_inst_declaration_hint)
-            << Function;
+              << Function;
       }
     }
 
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index d853805bf97e..04ade0a3b9d0 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -1462,18 +1462,19 @@ bool ASTReader::ReadSLocEntry(int ID) {
     unsigned RecCode = MaybeRecCode.get();
 
     if (RecCode == SM_SLOC_BUFFER_BLOB_COMPRESSED) {
-      if (!llvm::zlib::isAvailable()) {
+      if (!llvm::compression::zlib::isAvailable()) {
         Error("zlib is not available");
         return nullptr;
       }
-      SmallString<0> Uncompressed;
-      if (llvm::Error E =
-              llvm::zlib::uncompress(Blob, Uncompressed, Record[0])) {
+      SmallVector<uint8_t, 0> Uncompressed;
+      if (llvm::Error E = llvm::compression::zlib::uncompress(
+              llvm::arrayRefFromStringRef(Blob), Uncompressed, Record[0])) {
         Error("could not decompress embedded file contents: " +
               llvm::toString(std::move(E)));
         return nullptr;
       }
-      return llvm::MemoryBuffer::getMemBufferCopy(Uncompressed, Name);
+      return llvm::MemoryBuffer::getMemBufferCopy(
+          llvm::toStringRef(Uncompressed), Name);
     } else if (RecCode == SM_SLOC_BUFFER_BLOB) {
       return llvm::MemoryBuffer::getMemBuffer(Blob.drop_back(1), Name, true);
     } else {
@@ -5171,8 +5172,9 @@ namespace {
     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
                                  bool Complain,
                                  std::string &SuggestedPredefines) override {
-      return checkPreprocessorOptions(ExistingPPOpts, PPOpts, nullptr, FileMgr,
-                                      SuggestedPredefines, ExistingLangOpts);
+      return checkPreprocessorOptions(PPOpts, ExistingPPOpts, /*Diags=*/nullptr,
+                                      FileMgr, SuggestedPredefines,
+                                      ExistingLangOpts);
     }
   };
 
diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 1787909bb6f7..fac8fc141d2c 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -1888,8 +1888,8 @@ void ASTWriter::WriteHeaderSearch(const HeaderSearch &HS) {
         // without this file existing on disk.
         if (!U.Size || (!U.ModTime && IncludeTimestamps)) {
           PP->Diag(U.FileNameLoc, diag::err_module_no_size_mtime_for_header)
-            << WritingModule->getFullModuleName() << U.Size.hasValue()
-            << U.FileName;
+              << WritingModule->getFullModuleName() << U.Size.has_value()
+              << U.FileName;
           continue;
         }
 
@@ -2000,12 +2000,13 @@ static void emitBlob(llvm::BitstreamWriter &Stream, StringRef Blob,
 
   // Compress the buffer if possible. We expect that almost all PCM
   // consumers will not want its contents.
-  SmallString<0> CompressedBuffer;
-  if (llvm::zlib::isAvailable()) {
-    llvm::zlib::compress(Blob.drop_back(1), CompressedBuffer);
+  SmallVector<uint8_t, 0> CompressedBuffer;
+  if (llvm::compression::zlib::isAvailable()) {
+    llvm::compression::zlib::compress(
+        llvm::arrayRefFromStringRef(Blob.drop_back(1)), CompressedBuffer);
     RecordDataType Record[] = {SM_SLOC_BUFFER_BLOB_COMPRESSED, Blob.size() - 1};
     Stream.EmitRecordWithBlob(SLocBufferBlobCompressedAbbrv, Record,
-                              CompressedBuffer);
+                              llvm::toStringRef(CompressedBuffer));
     return;
   }
 
diff --git a/clang/lib/StaticAnalyzer/Checkers/BasicObjCFoundationChecks.cpp b/clang/lib/StaticAnalyzer/Checkers/BasicObjCFoundationChecks.cpp
index 330ca90b7659..ca76e2d83381 100644
--- a/clang/lib/StaticAnalyzer/Checkers/BasicObjCFoundationChecks.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/BasicObjCFoundationChecks.cpp
@@ -769,7 +769,7 @@ void VariadicMethodTypeChecker::checkPreObjCMessage(const ObjCMethodCall &msg,
     if (!errorNode)
       errorNode = C.generateNonFatalErrorNode();
 
-    if (!errorNode.getValue())
+    if (!errorNode.value())
       continue;
 
     SmallString<128> sbuf;
@@ -787,7 +787,7 @@ void VariadicMethodTypeChecker::checkPreObjCMessage(const ObjCMethodCall &msg,
     os << "'";
 
     auto R = std::make_unique<PathSensitiveBugReport>(*BT, os.str(),
-                                                      errorNode.getValue());
+                                                      errorNode.value());
     R->addRange(msg.getArgSourceRange(I));
     C.emitReport(std::move(R));
   }
diff --git a/clang/lib/StaticAnalyzer/Checkers/CStringChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
index 2e4c8e643698..987cf65d6fec 100644
--- a/clang/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
@@ -848,7 +848,7 @@ SVal CStringChecker::getCStringLength(CheckerContext &C, ProgramStateRef &state,
     SValBuilder &svalBuilder = C.getSValBuilder();
     QualType sizeTy = svalBuilder.getContext().getSizeType();
     const StringLiteral *strLit = cast<StringRegion>(MR)->getStringLiteral();
-    return svalBuilder.makeIntVal(strLit->getByteLength(), sizeTy);
+    return svalBuilder.makeIntVal(strLit->getLength(), sizeTy);
   }
   case MemRegion::SymbolicRegionKind:
   case MemRegion::AllocaRegionKind:
diff --git a/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
index 92d7cef78b13..36464707d06a 100644
--- a/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
@@ -1189,9 +1189,10 @@ MallocChecker::performKernelMalloc(const CallEvent &Call, CheckerContext &C,
   }
 
   NonLoc Flags = V.castAs<NonLoc>();
-  NonLoc ZeroFlag = C.getSValBuilder()
-      .makeIntVal(KernelZeroFlagVal.getValue(), FlagsEx->getType())
-      .castAs<NonLoc>();
+  NonLoc ZeroFlag =
+      C.getSValBuilder()
+          .makeIntVal(KernelZeroFlagVal.value(), FlagsEx->getType())
+          .castAs<NonLoc>();
   SVal MaskedFlagsUC = C.getSValBuilder().evalBinOpNN(State, BO_And,
                                                       Flags, ZeroFlag,
                                                       FlagsEx->getType());
@@ -1239,7 +1240,7 @@ void MallocChecker::checkKernelMalloc(const CallEvent &Call,
   llvm::Optional<ProgramStateRef> MaybeState =
       performKernelMalloc(Call, C, State);
   if (MaybeState)
-    State = MaybeState.getValue();
+    State = MaybeState.value();
   else
     State = MallocMemAux(C, Call, Call.getArgExpr(0), UndefinedVal(), State,
                          AF_Malloc);
diff --git a/clang/lib/StaticAnalyzer/Checkers/NonNullParamChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/NonNullParamChecker.cpp
index 3481936e572b..fb6afd0fdabc 100644
--- a/clang/lib/StaticAnalyzer/Checkers/NonNullParamChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/NonNullParamChecker.cpp
@@ -136,10 +136,10 @@ void NonNullParamChecker::checkPreCall(const CallEvent &Call,
     if (!DV)
       continue;
 
-    assert(!HasRefTypeParam || isa<Loc>(DV.getValue()));
+    assert(!HasRefTypeParam || isa<Loc>(DV.value()));
 
     // Process the case when the argument is not a location.
-    if (ExpectedToBeNonNull && !isa<Loc>(DV.getValue())) {
+    if (ExpectedToBeNonNull && !isa<Loc>(DV.value())) {
       // If the argument is a union type, we want to handle a potential
       // transparent_union GCC extension.
       if (!ArgE)
diff --git a/clang/lib/StaticAnalyzer/Checkers/UnixAPIChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/UnixAPIChecker.cpp
index 9da44d5c0d39..aa3f4524798a 100644
--- a/clang/lib/StaticAnalyzer/Checkers/UnixAPIChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/UnixAPIChecker.cpp
@@ -234,7 +234,8 @@ void UnixAPIMisuseChecker::CheckOpenVariant(CheckerContext &C,
   }
   NonLoc oflags = V.castAs<NonLoc>();
   NonLoc ocreateFlag = C.getSValBuilder()
-      .makeIntVal(Val_O_CREAT.getValue(), oflagsEx->getType()).castAs<NonLoc>();
+                           .makeIntVal(Val_O_CREAT.value(), oflagsEx->getType())
+                           .castAs<NonLoc>();
   SVal maskedFlagsUC = C.getSValBuilder().evalBinOpNN(state, BO_And,
                                                       oflags, ocreateFlag,
                                                       oflagsEx->getType());
diff --git a/clang/lib/StaticAnalyzer/Core/AnalyzerOptions.cpp b/clang/lib/StaticAnalyzer/Core/AnalyzerOptions.cpp
index 79d19a3b99f2..009cbd4559b5 100644
--- a/clang/lib/StaticAnalyzer/Core/AnalyzerOptions.cpp
+++ b/clang/lib/StaticAnalyzer/Core/AnalyzerOptions.cpp
@@ -78,7 +78,7 @@ AnalyzerOptions::getExplorationStrategy() const {
                 ExplorationStrategyKind::BFSBlockDFSContents)
           .Default(None);
   assert(K && "User mode is invalid.");
-  return K.getValue();
+  return K.value();
 }
 
 CTUPhase1InliningKind AnalyzerOptions::getCTUPhase1Inlining() const {
@@ -89,7 +89,7 @@ CTUPhase1InliningKind AnalyzerOptions::getCTUPhase1Inlining() const {
                .Case("all", CTUPhase1InliningKind::All)
                .Default(None);
   assert(K && "CTU inlining mode is invalid.");
-  return K.getValue();
+  return K.value();
 }
 
 IPAKind AnalyzerOptions::getIPAMode() const {
@@ -102,7 +102,7 @@ IPAKind AnalyzerOptions::getIPAMode() const {
           .Default(None);
   assert(K && "IPA Mode is invalid.");
 
-  return K.getValue();
+  return K.value();
 }
 
 bool
diff --git a/clang/lib/StaticAnalyzer/Core/BugReporter.cpp b/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
index a2efe14f1045..4d6b82e63f6a 100644
--- a/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugReporter.cpp
@@ -2363,15 +2363,15 @@ PathSensitiveBugReport::getInterestingnessKind(const MemRegion *R) const {
 }
 
 bool PathSensitiveBugReport::isInteresting(SVal V) const {
-  return getInterestingnessKind(V).hasValue();
+  return getInterestingnessKind(V).has_value();
 }
 
 bool PathSensitiveBugReport::isInteresting(SymbolRef sym) const {
-  return getInterestingnessKind(sym).hasValue();
+  return getInterestingnessKind(sym).has_value();
 }
 
 bool PathSensitiveBugReport::isInteresting(const MemRegion *R) const {
-  return getInterestingnessKind(R).hasValue();
+  return getInterestingnessKind(R).has_value();
 }
 
 bool PathSensitiveBugReport::isInteresting(const LocationContext *LC)  const {
diff --git a/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp b/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
index 5b72c91ccd74..2caa5bbc16df 100644
--- a/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
@@ -2950,7 +2950,7 @@ PathDiagnosticPieceRef ConditionBRVisitor::VisitTrueTest(
   PathDiagnosticLocation Loc(Cond, SM, LCtx);
   auto event = std::make_shared<PathDiagnosticEventPiece>(Loc, Message);
   if (shouldPrune)
-    event->setPrunable(shouldPrune.getValue());
+    event->setPrunable(shouldPrune.value());
   return event;
 }
 
@@ -3084,9 +3084,9 @@ bool ConditionBRVisitor::printValue(const Expr *CondVarExpr, raw_ostream &Out,
       Out << (TookTrue ? "not equal to 0" : "0");
   } else {
     if (Ty->isBooleanType())
-      Out << (IntValue.getValue()->getBoolValue() ? "true" : "false");
+      Out << (IntValue.value()->getBoolValue() ? "true" : "false");
     else
-      Out << *IntValue.getValue();
+      Out << *IntValue.value();
   }
 
   return true;
@@ -3282,7 +3282,7 @@ void FalsePositiveRefutationBRVisitor::finalizeVisitor(
   if (!IsSAT)
     return;
 
-  if (!IsSAT.getValue())
+  if (!IsSAT.value())
     BR.markInvalid("Infeasible constraints", EndPathNode->getLocationContext());
 }
 
diff --git a/clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp b/clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
index 5f8a84591b2a..e1649f0b3df6 100644
--- a/clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
+++ b/clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
@@ -1016,7 +1016,7 @@ bool ExprEngine::shouldInlineCall(const CallEvent &Call, const Decl *D,
   // Check if this function has been marked as non-inlinable.
   Optional<bool> MayInline = Engine.FunctionSummaries->mayInline(D);
   if (MayInline) {
-    if (!MayInline.getValue())
+    if (!MayInline.value())
       return false;
 
   } else {
diff --git a/clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp b/clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
index 93c19a688b9a..d35646bfba91 100644
--- a/clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
+++ b/clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
@@ -407,11 +407,11 @@ void PlistPrinter::ReportMacroExpansions(raw_ostream &o, unsigned indent) {
 
     // Output the macro name.
     Indent(o, indent) << "<key>name</key>";
-    EmitString(o, MacroName.getValue()) << '\n';
+    EmitString(o, MacroName.value()) << '\n';
 
     // Output what it expands into.
     Indent(o, indent) << "<key>expansion</key>";
-    EmitString(o, ExpansionText.getValue()) << '\n';
+    EmitString(o, ExpansionText.value()) << '\n';
 
     // Finish up.
     --indent;
diff --git a/clang/lib/StaticAnalyzer/Core/SValBuilder.cpp b/clang/lib/StaticAnalyzer/Core/SValBuilder.cpp
index 13fac37899cd..cf3d13ffb7ba 100644
--- a/clang/lib/StaticAnalyzer/Core/SValBuilder.cpp
+++ b/clang/lib/StaticAnalyzer/Core/SValBuilder.cpp
@@ -113,6 +113,8 @@ nonloc::SymbolVal SValBuilder::makeNonLoc(const SymExpr *operand,
                                           QualType fromTy, QualType toTy) {
   assert(operand);
   assert(!Loc::isLocType(toTy));
+  if (fromTy == toTy)
+    return operand;
   return nonloc::SymbolVal(SymMgr.getCastSymbol(operand, fromTy, toTy));
 }
 
@@ -1101,6 +1103,10 @@ nonloc::SymbolVal SValBuilder::simplifySymbolCast(nonloc::SymbolVal V,
   SymbolRef RootSym = cast<SymbolCast>(SE)->getOperand();
   QualType RT = RootSym->getType().getCanonicalType();
 
+  // FIXME support simplification from non-integers.
+  if (!RT->isIntegralOrEnumerationType())
+    return makeNonLoc(SE, T, CastTy);
+
   BasicValueFactory &BVF = getBasicValueFactory();
   APSIntType CTy = BVF.getAPSIntType(CastTy);
   APSIntType TTy = BVF.getAPSIntType(T);
diff --git a/clang/lib/Support/RISCVVIntrinsicUtils.cpp b/clang/lib/Support/RISCVVIntrinsicUtils.cpp
index d4d3f22c9327..19eb65b39b0a 100644
--- a/clang/lib/Support/RISCVVIntrinsicUtils.cpp
+++ b/clang/lib/Support/RISCVVIntrinsicUtils.cpp
@@ -114,7 +114,7 @@ bool RVVType::verifyType() const {
     return false;
   if (isFloat() && ElementBitwidth == 8)
     return false;
-  unsigned V = Scale.getValue();
+  unsigned V = Scale.value();
   switch (ElementBitwidth) {
   case 1:
   case 8:
@@ -798,7 +798,7 @@ RVVType::computeTypes(BasicType BT, int Log2LMUL, unsigned NF,
     if (!T)
       return llvm::None;
     // Record legal type index
-    Types.push_back(T.getValue());
+    Types.push_back(T.value());
   }
   return Types;
 }
diff --git a/clang/lib/Tooling/DependencyScanning/DependencyScanningTool.cpp b/clang/lib/Tooling/DependencyScanning/DependencyScanningTool.cpp
index 26c2b2b2f394..43127ea2df98 100644
--- a/clang/lib/Tooling/DependencyScanning/DependencyScanningTool.cpp
+++ b/clang/lib/Tooling/DependencyScanning/DependencyScanningTool.cpp
@@ -9,16 +9,19 @@
 #include "clang/Tooling/DependencyScanning/DependencyScanningTool.h"
 #include "clang/Frontend/Utils.h"
 
-namespace clang {
-namespace tooling {
-namespace dependencies {
+using namespace clang;
+using namespace tooling;
+using namespace dependencies;
 
 std::vector<std::string> FullDependencies::getCommandLine(
-    std::function<StringRef(ModuleID)> LookupPCMPath) const {
+    llvm::function_ref<std::string(const ModuleID &, ModuleOutputKind)>
+        LookupModuleOutput) const {
   std::vector<std::string> Ret = getCommandLineWithoutModulePaths();
 
-  for (ModuleID MID : ClangModuleDeps)
-    Ret.push_back(("-fmodule-file=" + LookupPCMPath(MID)).str());
+  for (ModuleID MID : ClangModuleDeps) {
+    auto PCM = LookupModuleOutput(MID, ModuleOutputKind::ModuleFile);
+    Ret.push_back("-fmodule-file=" + PCM);
+  }
 
   return Ret;
 }
@@ -192,7 +195,3 @@ DependencyScanningTool::getFullDependencies(
     return std::move(Result);
   return Consumer.getFullDependencies(CommandLine);
 }
-
-} // end namespace dependencies
-} // end namespace tooling
-} // end namespace clang
diff --git a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
index f7d96130b971..725bb2c318ac 100644
--- a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
+++ b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
@@ -8,6 +8,7 @@
 
 #include "clang/Tooling/DependencyScanning/ModuleDepCollector.h"
 
+#include "clang/Basic/MakeSupport.h"
 #include "clang/Frontend/CompilerInstance.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Tooling/DependencyScanning/DependencyScanningWorker.h"
@@ -56,6 +57,9 @@ CompilerInvocation ModuleDepCollector::makeInvocationForModuleBuildWithoutPaths(
   CI.getFrontendOpts().OutputFile.clear();
   CI.getCodeGenOpts().MainFileName.clear();
   CI.getCodeGenOpts().DwarfDebugFlags.clear();
+  CI.getDiagnosticOpts().DiagnosticSerializationFile.clear();
+  CI.getDependencyOutputOpts().OutputFile.clear();
+  CI.getDependencyOutputOpts().Targets.clear();
 
   CI.getFrontendOpts().ProgramAction = frontend::GenerateModule;
   CI.getLangOpts()->ModuleName = Deps.ID.ModuleName;
@@ -107,18 +111,47 @@ serializeCompilerInvocation(const CompilerInvocation &CI) {
   return std::vector<std::string>{Args.begin(), Args.end()};
 }
 
+static std::vector<std::string> splitString(std::string S, char Separator) {
+  SmallVector<StringRef> Segments;
+  StringRef(S).split(Segments, Separator, /*MaxSplit=*/-1, /*KeepEmpty=*/false);
+  std::vector<std::string> Result;
+  Result.reserve(Segments.size());
+  for (StringRef Segment : Segments)
+    Result.push_back(Segment.str());
+  return Result;
+}
+
 std::vector<std::string> ModuleDeps::getCanonicalCommandLine(
-    std::function<StringRef(ModuleID)> LookupPCMPath) const {
+    llvm::function_ref<std::string(const ModuleID &, ModuleOutputKind)>
+        LookupModuleOutput) const {
   CompilerInvocation CI(BuildInvocation);
   FrontendOptions &FrontendOpts = CI.getFrontendOpts();
 
   InputKind ModuleMapInputKind(FrontendOpts.DashX.getLanguage(),
                                InputKind::Format::ModuleMap);
   FrontendOpts.Inputs.emplace_back(ClangModuleMapFile, ModuleMapInputKind);
-  FrontendOpts.OutputFile = std::string(LookupPCMPath(ID));
+  FrontendOpts.OutputFile =
+      LookupModuleOutput(ID, ModuleOutputKind::ModuleFile);
+  if (HadSerializedDiagnostics)
+    CI.getDiagnosticOpts().DiagnosticSerializationFile =
+        LookupModuleOutput(ID, ModuleOutputKind::DiagnosticSerializationFile);
+  if (HadDependencyFile) {
+    DependencyOutputOptions &DepOpts = CI.getDependencyOutputOpts();
+    DepOpts.OutputFile =
+        LookupModuleOutput(ID, ModuleOutputKind::DependencyFile);
+    DepOpts.Targets = splitString(
+        LookupModuleOutput(ID, ModuleOutputKind::DependencyTargets), '\0');
+    if (!DepOpts.OutputFile.empty() && DepOpts.Targets.empty()) {
+      // Fallback to -o as dependency target, as in the driver.
+      SmallString<128> Target;
+      quoteMakeTarget(FrontendOpts.OutputFile, Target);
+      DepOpts.Targets.push_back(std::string(Target));
+    }
+  }
 
   for (ModuleID MID : ClangModuleDeps)
-    FrontendOpts.ModuleFiles.emplace_back(LookupPCMPath(MID));
+    FrontendOpts.ModuleFiles.push_back(
+        LookupModuleOutput(MID, ModuleOutputKind::ModuleFile));
 
   return serializeCompilerInvocation(CI);
 }
@@ -309,6 +342,12 @@ ModuleID ModuleDepCollectorPP::handleTopLevelModule(const Module *M) {
           optimizeHeaderSearchOpts(BuildInvocation.getHeaderSearchOpts(),
                                    *MDC.ScanInstance.getASTReader(), *MF);
       });
+  MD.HadSerializedDiagnostics = !MDC.OriginalInvocation.getDiagnosticOpts()
+                                     .DiagnosticSerializationFile.empty();
+  MD.HadDependencyFile =
+      !MDC.OriginalInvocation.getDependencyOutputOpts().OutputFile.empty();
+  // FIXME: HadSerializedDiagnostics and HadDependencyFile should be included in
+  // the context hash since it can affect the command-line.
   MD.ID.ContextHash = MD.BuildInvocation.getModuleHash();
 
   llvm::DenseSet<const Module *> AddedModules;
diff --git a/clang/tools/clang-format/ClangFormat.cpp b/clang/tools/clang-format/ClangFormat.cpp
index 07110a0db091..269bc59506b2 100644
--- a/clang/tools/clang-format/ClangFormat.cpp
+++ b/clang/tools/clang-format/ClangFormat.cpp
@@ -70,16 +70,18 @@ static cl::opt<std::string>
                   cl::desc("The name of the predefined style used as a\n"
                            "fallback in case clang-format is invoked with\n"
                            "-style=file, but can not find the .clang-format\n"
-                           "file to use.\n"
+                           "file to use. Defaults to 'LLVM'.\n"
                            "Use -fallback-style=none to skip formatting."),
                   cl::init(clang::format::DefaultFallbackStyle),
                   cl::cat(ClangFormatCategory));
 
 static cl::opt<std::string> AssumeFileName(
     "assume-filename",
-    cl::desc("Override filename used to determine the language.\n"
-             "When reading from stdin, clang-format assumes this\n"
-             "filename to determine the language.\n"
+    cl::desc("Set filename used to determine the language and to find\n"
+             ".clang-format file.\n"
+             "Only used when reading from stdin.\n"
+             "If this is not passed, the .clang-format file is searched\n"
+             "relative to the current working directory when reading stdin.\n"
              "Unrecognized filenames are treated as C++.\n"
              "supported:\n"
              "  CSharp: .cs\n"
@@ -244,8 +246,12 @@ static bool fillRanges(MemoryBuffer *Code,
         errs() << "error: invalid <start line>:<end line> pair\n";
         return true;
       }
+      if (FromLine < 1) {
+        errs() << "error: start line should be at least 1\n";
+        return true;
+      }
       if (FromLine > ToLine) {
-        errs() << "error: start line should be less than end line\n";
+        errs() << "error: start line should not exceed end line\n";
         return true;
       }
       SourceLocation Start = Sources.translateLineCol(ID, FromLine, 1);
diff --git a/clang/tools/driver/driver.cpp b/clang/tools/driver/driver.cpp
index 0e21106535ec..34335a599a00 100644
--- a/clang/tools/driver/driver.cpp
+++ b/clang/tools/driver/driver.cpp
@@ -408,7 +408,7 @@ int clang_main(int Argc, char **Argv) {
     llvm::Optional<std::string> OptCL = llvm::sys::Process::GetEnv("CL");
     if (OptCL) {
       SmallVector<const char *, 8> PrependedOpts;
-      getCLEnvVarOptions(OptCL.getValue(), Saver, PrependedOpts);
+      getCLEnvVarOptions(OptCL.value(), Saver, PrependedOpts);
 
       // Insert right after the program name to prepend to the argument list.
       Args.insert(Args.begin() + 1, PrependedOpts.begin(), PrependedOpts.end());
@@ -417,7 +417,7 @@ int clang_main(int Argc, char **Argv) {
     llvm::Optional<std::string> Opt_CL_ = llvm::sys::Process::GetEnv("_CL_");
     if (Opt_CL_) {
       SmallVector<const char *, 8> AppendedOpts;
-      getCLEnvVarOptions(Opt_CL_.getValue(), Saver, AppendedOpts);
+      getCLEnvVarOptions(Opt_CL_.value(), Saver, AppendedOpts);
 
       // Insert at the end of the argument list to append.
       Args.append(AppendedOpts.begin(), AppendedOpts.end());
diff --git a/clang/utils/TableGen/RISCVVEmitter.cpp b/clang/utils/TableGen/RISCVVEmitter.cpp
index 068e6a0c072c..db4cd77d8c53 100644
--- a/clang/utils/TableGen/RISCVVEmitter.cpp
+++ b/clang/utils/TableGen/RISCVVEmitter.cpp
@@ -105,6 +105,16 @@ void emitCodeGenSwitchBody(const RVVIntrinsic *RVVI, raw_ostream &OS) {
     return;
   }
 
+  // Cast pointer operand of vector load intrinsic.
+  for (const auto &I : enumerate(RVVI->getInputTypes())) {
+    if (I.value()->isPointer()) {
+      assert(RVVI->getIntrinsicTypes().front() == -1 &&
+             "RVVI should be vector load intrinsic.");
+      OS << "  Ops[" << I.index() << "] = Builder.CreateBitCast(Ops[";
+      OS << I.index() << "], ResultType->getPointerTo());\n";
+    }
+  }
+
   if (RVVI->isMasked()) {
     if (RVVI->hasVL()) {
       OS << "  std::rotate(Ops.begin(), Ops.begin() + 1, Ops.end() - 1);\n";
@@ -218,7 +228,7 @@ void RVVEmitter::createHeader(raw_ostream &OS) {
     auto T = RVVType::computeType(BasicType::Int8, Log2LMUL,
                                   PrototypeDescriptor::Mask);
     if (T)
-      printType(T.getValue());
+      printType(T.value());
   }
   // Print RVV int/float types.
   for (char I : StringRef("csil")) {
@@ -226,13 +236,13 @@ void RVVEmitter::createHeader(raw_ostream &OS) {
     for (int Log2LMUL : Log2LMULs) {
       auto T = RVVType::computeType(BT, Log2LMUL, PrototypeDescriptor::Vector);
       if (T) {
-        printType(T.getValue());
+        printType(T.value());
         auto UT = RVVType::computeType(
             BT, Log2LMUL,
             PrototypeDescriptor(BaseTypeModifier::Vector,
                                 VectorTypeModifier::NoModifier,
                                 TypeModifier::UnsignedInteger));
-        printType(UT.getValue());
+        printType(UT.value());
       }
     }
   }
@@ -241,7 +251,7 @@ void RVVEmitter::createHeader(raw_ostream &OS) {
     auto T = RVVType::computeType(BasicType::Float16, Log2LMUL,
                                   PrototypeDescriptor::Vector);
     if (T)
-      printType(T.getValue());
+      printType(T.value());
   }
   OS << "#endif\n";
 
@@ -250,7 +260,7 @@ void RVVEmitter::createHeader(raw_ostream &OS) {
     auto T = RVVType::computeType(BasicType::Float32, Log2LMUL,
                                   PrototypeDescriptor::Vector);
     if (T)
-      printType(T.getValue());
+      printType(T.value());
   }
   OS << "#endif\n";
 
@@ -259,7 +269,7 @@ void RVVEmitter::createHeader(raw_ostream &OS) {
     auto T = RVVType::computeType(BasicType::Float64, Log2LMUL,
                                   PrototypeDescriptor::Vector);
     if (T)
-      printType(T.getValue());
+      printType(T.value());
   }
   OS << "#endif\n\n";