vendor/clang/clang-trunk-r366426

1 files changed, 325 insertions, 92 deletions

diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index 41f8721468a3..f6ee7ee26d4b 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -1,9 +1,8 @@
 //===--- CGDebugInfo.cpp - Emit Debug Information for a Module ------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 //
@@ -19,6 +18,7 @@
 #include "CodeGenFunction.h"
 #include "CodeGenModule.h"
 #include "ConstantEmitter.h"
+#include "clang/Analysis/Analyses/ExprMutationAnalyzer.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclFriend.h"
 #include "clang/AST/DeclObjC.h"
@@ -373,7 +373,7 @@ CGDebugInfo::computeChecksum(FileID FID, SmallString<32> &Checksum) const {
 
   SourceManager &SM = CGM.getContext().getSourceManager();
   bool Invalid;
-  llvm::MemoryBuffer *MemBuffer = SM.getBuffer(FID, &Invalid);
+  const llvm::MemoryBuffer *MemBuffer = SM.getBuffer(FID, &Invalid);
   if (Invalid)
     return None;
 
@@ -423,8 +423,12 @@ llvm::DIFile *CGDebugInfo::getOrCreateFile(SourceLocation Loc) {
   }
 
   SmallString<32> Checksum;
+
+  // Compute the checksum if possible. If the location is affected by a #line
+  // directive that refers to a file, PLoc will have an invalid FileID, and we
+  // will correctly get no checksum.
   Optional<llvm::DIFile::ChecksumKind> CSKind =
-      computeChecksum(SM.getFileID(Loc), Checksum);
+      computeChecksum(PLoc.getFileID(), Checksum);
   Optional<llvm::DIFile::ChecksumInfo<StringRef>> CSInfo;
   if (CSKind)
     CSInfo.emplace(*CSKind, Checksum);
@@ -451,8 +455,8 @@ CGDebugInfo::createFile(StringRef FileName,
     for (; CurDirIt != CurDirE && *CurDirIt == *FileIt; ++CurDirIt, ++FileIt)
       llvm::sys::path::append(DirBuf, *CurDirIt);
     if (std::distance(llvm::sys::path::begin(CurDir), CurDirIt) == 1) {
-      // The common prefix only the root; stripping it would cause
-      // LLVM diagnostic locations to be more confusing.
+      // Don't strip the common prefix if it is only the root "/"
+      // since that would make LLVM diagnostic locations confusing.
       Dir = {};
       File = RemappedFile;
     } else {
@@ -610,12 +614,8 @@ void CGDebugInfo::CreateCompileUnit() {
   TheCU = DBuilder.createCompileUnit(
       LangTag, CUFile, CGOpts.EmitVersionIdentMetadata ? Producer : "",
       LO.Optimize || CGOpts.PrepareForLTO || CGOpts.PrepareForThinLTO,
-      CGOpts.DwarfDebugFlags, RuntimeVers,
-      (CGOpts.getSplitDwarfMode() != CodeGenOptions::NoFission)
-          ? ""
-          : CGOpts.SplitDwarfFile,
-      EmissionKind, DwoId, CGOpts.SplitDwarfInlining,
-      CGOpts.DebugInfoForProfiling,
+      CGOpts.DwarfDebugFlags, RuntimeVers, CGOpts.SplitDwarfFile, EmissionKind,
+      DwoId, CGOpts.SplitDwarfInlining, CGOpts.DebugInfoForProfiling,
       CGM.getTarget().getTriple().isNVPTX()
           ? llvm::DICompileUnit::DebugNameTableKind::None
           : static_cast<llvm::DICompileUnit::DebugNameTableKind>(
@@ -916,6 +916,11 @@ static SmallString<256> getTypeIdentifier(const TagType *Ty, CodeGenModule &CGM,
 
   if (!needsTypeIdentifier(TD, CGM, TheCU))
     return Identifier;
+  if (const auto *RD = dyn_cast<CXXRecordDecl>(TD))
+    if (RD->getDefinition())
+      if (RD->isDynamicClass() &&
+          CGM.getVTableLinkage(RD) == llvm::GlobalValue::ExternalLinkage)
+        return Identifier;
 
   // TODO: This is using the RTTI name. Is there a better way to get
   // a unique string for a type?
@@ -1083,15 +1088,18 @@ llvm::DIType *CGDebugInfo::CreateType(const TemplateSpecializationType *Ty,
   assert(Ty->isTypeAlias());
   llvm::DIType *Src = getOrCreateType(Ty->getAliasedType(), Unit);
 
+  auto *AliasDecl =
+      cast<TypeAliasTemplateDecl>(Ty->getTemplateName().getAsTemplateDecl())
+          ->getTemplatedDecl();
+
+  if (AliasDecl->hasAttr<NoDebugAttr>())
+    return Src;
+
   SmallString<128> NS;
   llvm::raw_svector_ostream OS(NS);
   Ty->getTemplateName().print(OS, getPrintingPolicy(), /*qualified*/ false);
   printTemplateArgumentList(OS, Ty->template_arguments(), getPrintingPolicy());
 
-  auto *AliasDecl =
-      cast<TypeAliasTemplateDecl>(Ty->getTemplateName().getAsTemplateDecl())
-          ->getTemplatedDecl();
-
   SourceLocation Loc = AliasDecl->getLocation();
   return DBuilder.createTypedef(Src, OS.str(), getOrCreateFile(Loc),
                                 getLineNumber(Loc),
@@ -1100,15 +1108,20 @@ llvm::DIType *CGDebugInfo::CreateType(const TemplateSpecializationType *Ty,
 
 llvm::DIType *CGDebugInfo::CreateType(const TypedefType *Ty,
                                       llvm::DIFile *Unit) {
+  llvm::DIType *Underlying =
+      getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit);
+
+  if (Ty->getDecl()->hasAttr<NoDebugAttr>())
+    return Underlying;
+
   // We don't set size information, but do specify where the typedef was
   // declared.
   SourceLocation Loc = Ty->getDecl()->getLocation();
 
   // Typedefs are derived from some other type.
-  return DBuilder.createTypedef(
-      getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit),
-      Ty->getDecl()->getName(), getOrCreateFile(Loc), getLineNumber(Loc),
-      getDeclContextDescriptor(Ty->getDecl()));
+  return DBuilder.createTypedef(Underlying, Ty->getDecl()->getName(),
+                                getOrCreateFile(Loc), getLineNumber(Loc),
+                                getDeclContextDescriptor(Ty->getDecl()));
 }
 
 static unsigned getDwarfCC(CallingConv CC) {
@@ -1394,6 +1407,9 @@ void CGDebugInfo::CollectRecordFields(
             isa<VarTemplateSpecializationDecl>(V))
           continue;
 
+        if (isa<VarTemplatePartialSpecializationDecl>(V))
+          continue;
+
         // Reuse the existing static member declaration if one exists
         auto MI = StaticDataMemberCache.find(V->getCanonicalDecl());
         if (MI != StaticDataMemberCache.end()) {
@@ -1726,31 +1742,37 @@ CGDebugInfo::CollectTemplateParams(const TemplateParameterList *TPList,
       QualType T = TA.getParamTypeForDecl().getDesugaredType(CGM.getContext());
       llvm::DIType *TTy = getOrCreateType(T, Unit);
       llvm::Constant *V = nullptr;
-      const CXXMethodDecl *MD;
-      // Variable pointer template parameters have a value that is the address
-      // of the variable.
-      if (const auto *VD = dyn_cast<VarDecl>(D))
-        V = CGM.GetAddrOfGlobalVar(VD);
-      // Member function pointers have special support for building them, though
-      // this is currently unsupported in LLVM CodeGen.
-      else if ((MD = dyn_cast<CXXMethodDecl>(D)) && MD->isInstance())
-        V = CGM.getCXXABI().EmitMemberFunctionPointer(MD);
-      else if (const auto *FD = dyn_cast<FunctionDecl>(D))
-        V = CGM.GetAddrOfFunction(FD);
-      // Member data pointers have special handling too to compute the fixed
-      // offset within the object.
-      else if (const auto *MPT = dyn_cast<MemberPointerType>(T.getTypePtr())) {
-        // These five lines (& possibly the above member function pointer
-        // handling) might be able to be refactored to use similar code in
-        // CodeGenModule::getMemberPointerConstant
-        uint64_t fieldOffset = CGM.getContext().getFieldOffset(D);
-        CharUnits chars =
-            CGM.getContext().toCharUnitsFromBits((int64_t)fieldOffset);
-        V = CGM.getCXXABI().EmitMemberDataPointer(MPT, chars);
+      // Skip retrieve the value if that template parameter has cuda device
+      // attribute, i.e. that value is not available at the host side.
+      if (!CGM.getLangOpts().CUDA || CGM.getLangOpts().CUDAIsDevice ||
+          !D->hasAttr<CUDADeviceAttr>()) {
+        const CXXMethodDecl *MD;
+        // Variable pointer template parameters have a value that is the address
+        // of the variable.
+        if (const auto *VD = dyn_cast<VarDecl>(D))
+          V = CGM.GetAddrOfGlobalVar(VD);
+        // Member function pointers have special support for building them,
+        // though this is currently unsupported in LLVM CodeGen.
+        else if ((MD = dyn_cast<CXXMethodDecl>(D)) && MD->isInstance())
+          V = CGM.getCXXABI().EmitMemberFunctionPointer(MD);
+        else if (const auto *FD = dyn_cast<FunctionDecl>(D))
+          V = CGM.GetAddrOfFunction(FD);
+        // Member data pointers have special handling too to compute the fixed
+        // offset within the object.
+        else if (const auto *MPT =
+                     dyn_cast<MemberPointerType>(T.getTypePtr())) {
+          // These five lines (& possibly the above member function pointer
+          // handling) might be able to be refactored to use similar code in
+          // CodeGenModule::getMemberPointerConstant
+          uint64_t fieldOffset = CGM.getContext().getFieldOffset(D);
+          CharUnits chars =
+              CGM.getContext().toCharUnitsFromBits((int64_t)fieldOffset);
+          V = CGM.getCXXABI().EmitMemberDataPointer(MPT, chars);
+        }
+        V = V->stripPointerCasts();
       }
       TemplateParams.push_back(DBuilder.createTemplateValueParameter(
-          TheCU, Name, TTy,
-          cast_or_null<llvm::Constant>(V->stripPointerCasts())));
+          TheCU, Name, TTy, cast_or_null<llvm::Constant>(V)));
     } break;
     case TemplateArgument::NullPtr: {
       QualType T = TA.getNullPtrType();
@@ -1817,32 +1839,24 @@ CGDebugInfo::CollectFunctionTemplateParams(const FunctionDecl *FD,
 }
 
 llvm::DINodeArray CGDebugInfo::CollectVarTemplateParams(const VarDecl *VL,
-    llvm::DIFile *Unit) {
-  if (auto *TS = dyn_cast<VarTemplateSpecializationDecl>(VL)) {
-    auto T = TS->getSpecializedTemplateOrPartial();
-    auto TA = TS->getTemplateArgs().asArray();
-    // Collect parameters for a partial specialization
-    if (T.is<VarTemplatePartialSpecializationDecl *>()) {
-      const TemplateParameterList *TList =
-        T.get<VarTemplatePartialSpecializationDecl *>()
-        ->getTemplateParameters();
-      return CollectTemplateParams(TList, TA, Unit);
-    }
-
-    // Collect parameters for an explicit specialization
-    if (T.is<VarTemplateDecl *>()) {
-      const TemplateParameterList *TList = T.get<VarTemplateDecl *>()
-        ->getTemplateParameters();
-      return CollectTemplateParams(TList, TA, Unit);
-    }
-  }
-  return llvm::DINodeArray();
+                                                        llvm::DIFile *Unit) {
+  // Always get the full list of parameters, not just the ones from the
+  // specialization. A partial specialization may have fewer parameters than
+  // there are arguments.
+  auto *TS = dyn_cast<VarTemplateSpecializationDecl>(VL);
+  if (!TS)
+    return llvm::DINodeArray();
+  VarTemplateDecl *T = TS->getSpecializedTemplate();
+  const TemplateParameterList *TList = T->getTemplateParameters();
+  auto TA = TS->getTemplateArgs().asArray();
+  return CollectTemplateParams(TList, TA, Unit);
 }
 
 llvm::DINodeArray CGDebugInfo::CollectCXXTemplateParams(
     const ClassTemplateSpecializationDecl *TSpecial, llvm::DIFile *Unit) {
-  // Always get the full list of parameters, not just the ones from
-  // the specialization.
+  // Always get the full list of parameters, not just the ones from the
+  // specialization. A partial specialization may have fewer parameters than
+  // there are arguments.
   TemplateParameterList *TPList =
       TSpecial->getSpecializedTemplate()->getTemplateParameters();
   const TemplateArgumentList &TAList = TSpecial->getTemplateArgs();
@@ -1875,6 +1889,58 @@ StringRef CGDebugInfo::getVTableName(const CXXRecordDecl *RD) {
   return internString("_vptr$", RD->getNameAsString());
 }
 
+StringRef CGDebugInfo::getDynamicInitializerName(const VarDecl *VD,
+                                                 DynamicInitKind StubKind,
+                                                 llvm::Function *InitFn) {
+  // If we're not emitting codeview, use the mangled name. For Itanium, this is
+  // arbitrary.
+  if (!CGM.getCodeGenOpts().EmitCodeView)
+    return InitFn->getName();
+
+  // Print the normal qualified name for the variable, then break off the last
+  // NNS, and add the appropriate other text. Clang always prints the global
+  // variable name without template arguments, so we can use rsplit("::") and
+  // then recombine the pieces.
+  SmallString<128> QualifiedGV;
+  StringRef Quals;
+  StringRef GVName;
+  {
+    llvm::raw_svector_ostream OS(QualifiedGV);
+    VD->printQualifiedName(OS, getPrintingPolicy());
+    std::tie(Quals, GVName) = OS.str().rsplit("::");
+    if (GVName.empty())
+      std::swap(Quals, GVName);
+  }
+
+  SmallString<128> InitName;
+  llvm::raw_svector_ostream OS(InitName);
+  if (!Quals.empty())
+    OS << Quals << "::";
+
+  switch (StubKind) {
+  case DynamicInitKind::NoStub:
+    llvm_unreachable("not an initializer");
+  case DynamicInitKind::Initializer:
+    OS << "`dynamic initializer for '";
+    break;
+  case DynamicInitKind::AtExit:
+    OS << "`dynamic atexit destructor for '";
+    break;
+  }
+
+  OS << GVName;
+
+  // Add any template specialization args.
+  if (const auto *VTpl = dyn_cast<VarTemplateSpecializationDecl>(VD)) {
+    printTemplateArgumentList(OS, VTpl->getTemplateArgs().asArray(),
+                              getPrintingPolicy());
+  }
+
+  OS << '\'';
+
+  return internString(OS.str());
+}
+
 void CGDebugInfo::CollectVTableInfo(const CXXRecordDecl *RD, llvm::DIFile *Unit,
                                     SmallVectorImpl<llvm::Metadata *> &EltTys,
                                     llvm::DICompositeType *RecordTy) {
@@ -1954,6 +2020,20 @@ llvm::DIType *CGDebugInfo::getOrCreateStandaloneType(QualType D,
   return T;
 }
 
+void CGDebugInfo::addHeapAllocSiteMetadata(llvm::Instruction *CI,
+                                           QualType D,
+                                           SourceLocation Loc) {
+  llvm::MDNode *node;
+  if (D.getTypePtr()->isVoidPointerType()) {
+    node = llvm::MDNode::get(CGM.getLLVMContext(), None);
+  } else {
+    QualType PointeeTy = D.getTypePtr()->getPointeeType();
+    node = getOrCreateType(PointeeTy, getOrCreateFile(Loc));
+  }
+
+  CI->setMetadata("heapallocsite", node);
+}
+
 void CGDebugInfo::completeType(const EnumDecl *ED) {
   if (DebugKind <= codegenoptions::DebugLineTablesOnly)
     return;
@@ -2297,7 +2377,14 @@ CGDebugInfo::getOrCreateModuleRef(ExternalASTSource::ASTSourceDescriptor Mod,
   }
 
   bool IsRootModule = M ? !M->Parent : true;
-  if (CreateSkeletonCU && IsRootModule) {
+  // When a module name is specified as -fmodule-name, that module gets a
+  // clang::Module object, but it won't actually be built or imported; it will
+  // be textual.
+  if (CreateSkeletonCU && IsRootModule && Mod.getASTFile().empty() && M)
+    assert(StringRef(M->Name).startswith(CGM.getLangOpts().ModuleName) &&
+           "clang module without ASTFile must be specified by -fmodule-name");
+
+  if (CreateSkeletonCU && IsRootModule && !Mod.getASTFile().empty()) {
     // PCH files don't have a signature field in the control block,
     // but LLVM detects skeleton CUs by looking for a non-zero DWO id.
     // We use the lower 64 bits for debug info.
@@ -2314,6 +2401,7 @@ CGDebugInfo::getOrCreateModuleRef(ExternalASTSource::ASTSourceDescriptor Mod,
                           Signature);
     DIB.finalize();
   }
+
   llvm::DIModule *Parent =
       IsRootModule ? nullptr
                    : getOrCreateModuleRef(
@@ -2768,6 +2856,9 @@ static QualType UnwrapTypeForDebugInfo(QualType T, const ASTContext &C) {
     case Type::Paren:
       T = cast<ParenType>(T)->getInnerType();
       break;
+    case Type::MacroQualified:
+      T = cast<MacroQualifiedType>(T)->getUnderlyingType();
+      break;
     case Type::SubstTemplateTypeParm:
       T = cast<SubstTemplateTypeParmType>(T)->getReplacementType();
       break;
@@ -2947,6 +3038,7 @@ llvm::DIType *CGDebugInfo::CreateTypeNode(QualType Ty, llvm::DIFile *Unit) {
   case Type::DeducedTemplateSpecialization:
   case Type::Elaborated:
   case Type::Paren:
+  case Type::MacroQualified:
   case Type::SubstTemplateTypeParm:
   case Type::TypeOfExpr:
   case Type::TypeOf:
@@ -3021,9 +3113,9 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
     else
       Flags |= llvm::DINode::FlagTypePassByValue;
 
-    // Record if a C++ record is trivial type.
-    if (CXXRD->isTrivial())
-      Flags |= llvm::DINode::FlagTrivial;
+    // Record if a C++ record is non-trivial type.
+    if (!CXXRD->isTrivial())
+      Flags |= llvm::DINode::FlagNonTrivial;
   }
 
   llvm::DICompositeType *RealDecl = DBuilder.createReplaceableCompositeType(
@@ -3443,6 +3535,11 @@ void CGDebugInfo::EmitFunctionStart(GlobalDecl GD, SourceLocation Loc,
   } else if (const auto *OMD = dyn_cast<ObjCMethodDecl>(D)) {
     Name = getObjCMethodName(OMD);
     Flags |= llvm::DINode::FlagPrototyped;
+  } else if (isa<VarDecl>(D) &&
+             GD.getDynamicInitKind() != DynamicInitKind::NoStub) {
+    // This is a global initializer or atexit destructor for a global variable.
+    Name = getDynamicInitializerName(cast<VarDecl>(D), GD.getDynamicInitKind(),
+                                     Fn);
   } else {
     // Use llvm function name.
     Name = Fn->getName();
@@ -3488,6 +3585,15 @@ void CGDebugInfo::EmitFunctionStart(GlobalDecl GD, SourceLocation Loc,
   if (HasDecl && isa<FunctionDecl>(D))
     DeclCache[D->getCanonicalDecl()].reset(SP);
 
+  // We use the SPDefCache only in the case when the debug entry values option
+  // is set, in order to speed up parameters modification analysis.
+  //
+  // FIXME: Use AbstractCallee here to support ObjCMethodDecl.
+  if (CGM.getCodeGenOpts().EnableDebugEntryValues && HasDecl)
+    if (auto *FD = dyn_cast<FunctionDecl>(D))
+      if (FD->hasBody() && !FD->param_empty())
+        SPDefCache[FD].reset(SP);
+
   if (CGM.getCodeGenOpts().DwarfVersion >= 5) {
     // Starting with DWARF V5 method declarations are emitted as children of
     // the interface type.
@@ -3516,7 +3622,7 @@ void CGDebugInfo::EmitFunctionStart(GlobalDecl GD, SourceLocation Loc,
 }
 
 void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
-                                   QualType FnType) {
+                                   QualType FnType, llvm::Function *Fn) {
   StringRef Name;
   StringRef LinkageName;
 
@@ -3526,7 +3632,9 @@ void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
 
   llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
   llvm::DIFile *Unit = getOrCreateFile(Loc);
-  llvm::DIScope *FDContext = getDeclContextDescriptor(D);
+  bool IsDeclForCallSite = Fn ? true : false;
+  llvm::DIScope *FDContext =
+      IsDeclForCallSite ? Unit : getDeclContextDescriptor(D);
   llvm::DINodeArray TParamsArray;
   if (isa<FunctionDecl>(D)) {
     // If there is a DISubprogram for this function available then use it.
@@ -3553,10 +3661,38 @@ void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
   if (CGM.getLangOpts().Optimize)
     SPFlags |= llvm::DISubprogram::SPFlagOptimized;
 
-  DBuilder.retainType(DBuilder.createFunction(
+  llvm::DISubprogram *SP = DBuilder.createFunction(
       FDContext, Name, LinkageName, Unit, LineNo,
       getOrCreateFunctionType(D, FnType, Unit), ScopeLine, Flags, SPFlags,
-      TParamsArray.get(), getFunctionDeclaration(D)));
+      TParamsArray.get(), getFunctionDeclaration(D));
+
+  if (IsDeclForCallSite)
+    Fn->setSubprogram(SP);
+
+  DBuilder.retainType(SP);
+}
+
+void CGDebugInfo::EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
+                                          QualType CalleeType,
+                                          const FunctionDecl *CalleeDecl) {
+  auto &CGOpts = CGM.getCodeGenOpts();
+  if (!CGOpts.EnableDebugEntryValues || !CGM.getLangOpts().Optimize ||
+      !CallOrInvoke ||
+      CGM.getCodeGenOpts().getDebugInfo() < codegenoptions::LimitedDebugInfo)
+    return;
+
+  auto *Func = CallOrInvoke->getCalledFunction();
+  if (!Func)
+    return;
+
+  // If there is no DISubprogram attached to the function being called,
+  // create the one describing the function in order to have complete
+  // call site debug info.
+  if (Func->getSubprogram())
+    return;
+
+  if (!CalleeDecl->isStatic() && !CalleeDecl->isInlined())
+    EmitFunctionDecl(CalleeDecl, CalleeDecl->getLocation(), CalleeType, Func);
 }
 
 void CGDebugInfo::EmitInlineFunctionStart(CGBuilderTy &Builder, GlobalDecl GD) {
@@ -3735,7 +3871,8 @@ CGDebugInfo::EmitTypeForVarWithBlocksAttr(const VarDecl *VD,
 llvm::DILocalVariable *CGDebugInfo::EmitDeclare(const VarDecl *VD,
                                                 llvm::Value *Storage,
                                                 llvm::Optional<unsigned> ArgNo,
-                                                CGBuilderTy &Builder) {
+                                                CGBuilderTy &Builder,
+                                                const bool UsePointerValue) {
   assert(DebugKind >= codegenoptions::LimitedDebugInfo);
   assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
   if (VD->hasAttr<NoDebugAttr>())
@@ -3840,6 +3977,16 @@ llvm::DILocalVariable *CGDebugInfo::EmitDeclare(const VarDecl *VD,
     }
   }
 
+  // Clang stores the sret pointer provided by the caller in a static alloca.
+  // Use DW_OP_deref to tell the debugger to load the pointer and treat it as
+  // the address of the variable.
+  if (UsePointerValue) {
+    assert(std::find(Expr.begin(), Expr.end(), llvm::dwarf::DW_OP_deref) ==
+               Expr.end() &&
+           "Debug info already contains DW_OP_deref.");
+    Expr.push_back(llvm::dwarf::DW_OP_deref);
+  }
+
   // Create the descriptor for the variable.
   auto *D = ArgNo ? DBuilder.createParameterVariable(
                         Scope, Name, *ArgNo, Unit, Line, Ty,
@@ -3853,14 +4000,46 @@ llvm::DILocalVariable *CGDebugInfo::EmitDeclare(const VarDecl *VD,
                          llvm::DebugLoc::get(Line, Column, Scope, CurInlinedAt),
                          Builder.GetInsertBlock());
 
+  if (CGM.getCodeGenOpts().EnableDebugEntryValues && ArgNo) {
+    if (auto *PD = dyn_cast<ParmVarDecl>(VD))
+      ParamCache[PD].reset(D);
+  }
+
   return D;
 }
 
 llvm::DILocalVariable *
 CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *VD, llvm::Value *Storage,
-                                       CGBuilderTy &Builder) {
+                                       CGBuilderTy &Builder,
+                                       const bool UsePointerValue) {
   assert(DebugKind >= codegenoptions::LimitedDebugInfo);
-  return EmitDeclare(VD, Storage, llvm::None, Builder);
+  return EmitDeclare(VD, Storage, llvm::None, Builder, UsePointerValue);
+}
+
+void CGDebugInfo::EmitLabel(const LabelDecl *D, CGBuilderTy &Builder) {
+  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
+
+  if (D->hasAttr<NoDebugAttr>())
+    return;
+
+  auto *Scope = cast<llvm::DIScope>(LexicalBlockStack.back());
+  llvm::DIFile *Unit = getOrCreateFile(D->getLocation());
+
+  // Get location information.
+  unsigned Line = getLineNumber(D->getLocation());
+  unsigned Column = getColumnNumber(D->getLocation());
+
+  StringRef Name = D->getName();
+
+  // Create the descriptor for the label.
+  auto *L =
+      DBuilder.createLabel(Scope, Name, Unit, Line, CGM.getLangOpts().Optimize);
+
+  // Insert an llvm.dbg.label into the current block.
+  DBuilder.insertLabel(L,
+                       llvm::DebugLoc::get(Line, Column, Scope, CurInlinedAt),
+                       Builder.GetInsertBlock());
 }
 
 llvm::DIType *CGDebugInfo::CreateSelfType(const QualType &QualTy,
@@ -4125,7 +4304,7 @@ void CGDebugInfo::EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
 
 llvm::DIDerivedType *
 CGDebugInfo::getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D) {
-  if (!D->isStaticDataMember())
+  if (!D || !D->isStaticDataMember())
     return nullptr;
 
   auto MI = StaticDataMemberCache.find(D->getCanonicalDecl());
@@ -4207,6 +4386,14 @@ void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
     SmallVector<int64_t, 4> Expr;
     unsigned AddressSpace =
         CGM.getContext().getTargetAddressSpace(D->getType());
+    if (CGM.getLangOpts().CUDA && CGM.getLangOpts().CUDAIsDevice) {
+      if (D->hasAttr<CUDASharedAttr>())
+        AddressSpace =
+            CGM.getContext().getTargetAddressSpace(LangAS::cuda_shared);
+      else if (D->hasAttr<CUDAConstantAttr>())
+        AddressSpace =
+            CGM.getContext().getTargetAddressSpace(LangAS::cuda_constant);
+    }
     AppendAddressSpaceXDeref(AddressSpace, Expr);
 
     GVE = DBuilder.createGlobalVariableExpression(
@@ -4229,22 +4416,32 @@ void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD, const APValue &Init) {
   llvm::DIFile *Unit = getOrCreateFile(VD->getLocation());
   StringRef Name = VD->getName();
   llvm::DIType *Ty = getOrCreateType(VD->getType(), Unit);
+
+  // Do not use global variables for enums, unless in CodeView.
   if (const auto *ECD = dyn_cast<EnumConstantDecl>(VD)) {
     const auto *ED = cast<EnumDecl>(ECD->getDeclContext());
     assert(isa<EnumType>(ED->getTypeForDecl()) && "Enum without EnumType?");
-    Ty = getOrCreateType(QualType(ED->getTypeForDecl(), 0), Unit);
+    (void)ED;
+
+    // If CodeView, emit enums as global variables, unless they are defined
+    // inside a class. We do this because MSVC doesn't emit S_CONSTANTs for
+    // enums in classes, and because it is difficult to attach this scope
+    // information to the global variable.
+    if (!CGM.getCodeGenOpts().EmitCodeView ||
+        isa<RecordDecl>(ED->getDeclContext()))
+      return;
   }
-  // Do not use global variables for enums.
-  //
-  // FIXME: why not?
-  if (Ty->getTag() == llvm::dwarf::DW_TAG_enumeration_type)
-    return;
-  // Do not emit separate definitions for function local const/statics.
+
+  llvm::DIScope *DContext = nullptr;
+
+  // Do not emit separate definitions for function local consts.
   if (isa<FunctionDecl>(VD->getDeclContext()))
     return;
+
+  // Emit definition for static members in CodeView.
   VD = cast<ValueDecl>(VD->getCanonicalDecl());
-  auto *VarD = cast<VarDecl>(VD);
-  if (VarD->isStaticDataMember()) {
+  auto *VarD = dyn_cast<VarDecl>(VD);
+  if (VarD && VarD->isStaticDataMember()) {
     auto *RD = cast<RecordDecl>(VarD->getDeclContext());
     getDeclContextDescriptor(VarD);
     // Ensure that the type is retained even though it's otherwise unreferenced.
@@ -4253,10 +4450,16 @@ void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD, const APValue &Init) {
     // through its scope.
     RetainedTypes.push_back(
         CGM.getContext().getRecordType(RD).getAsOpaquePtr());
-    return;
-  }
 
-  llvm::DIScope *DContext = getDeclContextDescriptor(VD);
+    if (!CGM.getCodeGenOpts().EmitCodeView)
+      return;
+
+    // Use the global scope for static members.
+    DContext = getContextDescriptor(
+        cast<Decl>(CGM.getContext().getTranslationUnitDecl()), TheCU);
+  } else {
+    DContext = getDeclContextDescriptor(VD);
+  }
 
   auto &GV = DeclCache[VD];
   if (GV)
@@ -4393,6 +4596,29 @@ void CGDebugInfo::setDwoId(uint64_t Signature) {
   TheCU->setDWOId(Signature);
 }
 
+/// Analyzes each function parameter to determine whether it is constant
+/// throughout the function body.
+static void analyzeParametersModification(
+    ASTContext &Ctx,
+    llvm::DenseMap<const FunctionDecl *, llvm::TrackingMDRef> &SPDefCache,
+    llvm::DenseMap<const ParmVarDecl *, llvm::TrackingMDRef> &ParamCache) {
+  for (auto &SP : SPDefCache) {
+    auto *FD = SP.first;
+    assert(FD->hasBody() && "Functions must have body here");
+    const Stmt *FuncBody = (*FD).getBody();
+    for (auto Parm : FD->parameters()) {
+      ExprMutationAnalyzer FuncAnalyzer(*FuncBody, Ctx);
+      if (FuncAnalyzer.isMutated(Parm))
+        continue;
+
+      auto I = ParamCache.find(Parm);
+      assert(I != ParamCache.end() && "Parameters should be already cached");
+      auto *DIParm = cast<llvm::DILocalVariable>(I->second);
+      DIParm->setIsNotModified();
+    }
+  }
+}
+
 void CGDebugInfo::finalize() {
   // Creating types might create further types - invalidating the current
   // element and the size(), so don't cache/reference them.
@@ -4465,6 +4691,10 @@ void CGDebugInfo::finalize() {
     if (auto MD = TypeCache[RT])
       DBuilder.retainType(cast<llvm::DIType>(MD));
 
+  if (CGM.getCodeGenOpts().EnableDebugEntryValues)
+    // This will be used to emit debug entry values.
+    analyzeParametersModification(CGM.getContext(), SPDefCache, ParamCache);
+
   DBuilder.finalize();
 }
 
@@ -4497,7 +4727,10 @@ llvm::DINode::DIFlags CGDebugInfo::getCallSiteRelatedAttrs() const {
   // were part of DWARF v4.
   bool SupportsDWARFv4Ext =
       CGM.getCodeGenOpts().DwarfVersion == 4 &&
-      CGM.getCodeGenOpts().getDebuggerTuning() == llvm::DebuggerKind::LLDB;
+      (CGM.getCodeGenOpts().getDebuggerTuning() == llvm::DebuggerKind::LLDB ||
+       (CGM.getCodeGenOpts().EnableDebugEntryValues &&
+       CGM.getCodeGenOpts().getDebuggerTuning() == llvm::DebuggerKind::GDB));
+
   if (!SupportsDWARFv4Ext && CGM.getCodeGenOpts().DwarfVersion < 5)
     return llvm::DINode::FlagZero;