[DebugInfo] Add another level to DebugInfoKind called Constructor

The option will limit debug info by only emitting complete class
type information when its constructor is emitted.
This patch changes comparisons with LimitedDebugInfo to use the new
level instead.

Differential Revision: https://reviews.llvm.org/D72427

clang/include/clang/Basic/CodeGenOptions.h

@@ -357,6 +357,11 @@ public:
 
   /// Check if CSIR profile use is on.
   bool hasProfileCSIRUse() const { return getProfileUse() == ProfileCSIRInstr; }
+
+  /// Check if type and variable info should be emitted.
+  bool hasReducedDebugInfo() const {
+    return getDebugInfo() >= codegenoptions::DebugInfoConstructor;
+  }
 };
 
 }  // end namespace clang

clang/include/clang/Basic/DebugInfoOptions.h

@@ -34,6 +34,11 @@ enum DebugInfoKind {
   /// (-gline-tables-only).
   DebugLineTablesOnly,
 
+  /// Limit generated debug info for classes to reduce size. This emits class
+  /// type info only where the constructor is emitted, if it is a class that
+  /// has a constructor.
+  DebugInfoConstructor,
+
   /// Limit generated debug info to reduce size (-fno-standalone-debug). This
   /// emits forward decls for types that could be replaced with forward decls in
   /// the source code. For dynamic C++ classes type info is only emitted into

clang/lib/CodeGen/CGBlocks.cpp

@@ -1483,8 +1483,7 @@ void CodeGenFunction::setBlockContextParameter(const ImplicitParamDecl *D,
   Address alloc = CreateMemTemp(D->getType(), D->getName() + ".addr");
   Builder.CreateStore(arg, alloc);
   if (CGDebugInfo *DI = getDebugInfo()) {
-    if (CGM.getCodeGenOpts().getDebugInfo() >=
+    if (CGM.getCodeGenOpts().hasReducedDebugInfo()) {
-        codegenoptions::LimitedDebugInfo) {
       DI->setLocation(D->getLocation());
       DI->EmitDeclareOfBlockLiteralArgVariable(
           *BlockInfo, D->getName(), argNum,
@@ -1656,8 +1655,7 @@ CodeGenFunction::GenerateBlockFunction(GlobalDecl GD,
       const VarDecl *variable = CI.getVariable();
       DI->EmitLocation(Builder, variable->getLocation());
 
-      if (CGM.getCodeGenOpts().getDebugInfo() >=
+      if (CGM.getCodeGenOpts().hasReducedDebugInfo()) {
-          codegenoptions::LimitedDebugInfo) {
         const CGBlockInfo::Capture &capture = blockInfo.getCapture(variable);
         if (capture.isConstant()) {
           auto addr = LocalDeclMap.find(variable)->second;

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -591,6 +591,7 @@ void CGDebugInfo::CreateCompileUnit() {
   case codegenoptions::DebugDirectivesOnly:
     EmissionKind = llvm::DICompileUnit::DebugDirectivesOnly;
     break;
+  case codegenoptions::DebugInfoConstructor:
   case codegenoptions::LimitedDebugInfo:
   case codegenoptions::FullDebugInfo:
     EmissionKind = llvm::DICompileUnit::FullDebug;
@@ -2043,7 +2044,7 @@ void CGDebugInfo::CollectVTableInfo(const CXXRecordDecl *RD, llvm::DIFile *Unit,
 
 llvm::DIType *CGDebugInfo::getOrCreateRecordType(QualType RTy,
                                                  SourceLocation Loc) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   llvm::DIType *T = getOrCreateType(RTy, getOrCreateFile(Loc));
   return T;
 }
@@ -2055,7 +2056,7 @@ llvm::DIType *CGDebugInfo::getOrCreateInterfaceType(QualType D,
 
 llvm::DIType *CGDebugInfo::getOrCreateStandaloneType(QualType D,
                                                      SourceLocation Loc) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   assert(!D.isNull() && "null type");
   llvm::DIType *T = getOrCreateType(D, getOrCreateFile(Loc));
   assert(T && "could not create debug info for type");
@@ -3270,7 +3271,7 @@ void CGDebugInfo::collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,
                               DebugKind <= codegenoptions::DebugLineTablesOnly))
     LinkageName = StringRef();
 
-  if (DebugKind >= codegenoptions::LimitedDebugInfo) {
+  if (CGM.getCodeGenOpts().hasReducedDebugInfo()) {
     if (const NamespaceDecl *NSDecl =
             dyn_cast_or_null<NamespaceDecl>(FD->getDeclContext()))
       FDContext = getOrCreateNamespace(NSDecl);
@@ -3957,7 +3958,7 @@ llvm::DILocalVariable *CGDebugInfo::EmitDeclare(const VarDecl *VD,
                                                 llvm::Optional<unsigned> ArgNo,
                                                 CGBuilderTy &Builder,
                                                 const bool UsePointerValue) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
   if (VD->hasAttr<NoDebugAttr>())
     return nullptr;
@@ -4091,12 +4092,12 @@ llvm::DILocalVariable *
 CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *VD, llvm::Value *Storage,
                                        CGBuilderTy &Builder,
                                        const bool UsePointerValue) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   return EmitDeclare(VD, Storage, llvm::None, Builder, UsePointerValue);
 }
 
 void CGDebugInfo::EmitLabel(const LabelDecl *D, CGBuilderTy &Builder) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
 
   if (D->hasAttr<NoDebugAttr>())
@@ -4132,7 +4133,7 @@ llvm::DIType *CGDebugInfo::CreateSelfType(const QualType &QualTy,
 void CGDebugInfo::EmitDeclareOfBlockDeclRefVariable(
     const VarDecl *VD, llvm::Value *Storage, CGBuilderTy &Builder,
     const CGBlockInfo &blockInfo, llvm::Instruction *InsertPoint) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
 
   if (Builder.GetInsertBlock() == nullptr)
@@ -4203,7 +4204,7 @@ void CGDebugInfo::EmitDeclareOfBlockDeclRefVariable(
 void CGDebugInfo::EmitDeclareOfArgVariable(const VarDecl *VD, llvm::Value *AI,
                                            unsigned ArgNo,
                                            CGBuilderTy &Builder) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   EmitDeclare(VD, AI, ArgNo, Builder);
 }
 
@@ -4260,7 +4261,7 @@ void CGDebugInfo::EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
                                                        unsigned ArgNo,
                                                        llvm::AllocaInst *Alloca,
                                                        CGBuilderTy &Builder) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   ASTContext &C = CGM.getContext();
   const BlockDecl *blockDecl = block.getBlockDecl();
 
@@ -4426,7 +4427,7 @@ llvm::DIGlobalVariableExpression *CGDebugInfo::CollectAnonRecordDecls(
 
 void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
                                      const VarDecl *D) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   if (D->hasAttr<NoDebugAttr>())
     return;
 
@@ -4495,7 +4496,7 @@ void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
 }
 
 void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD, const APValue &Init) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   if (VD->hasAttr<NoDebugAttr>())
     return;
   llvm::TimeTraceScope TimeScope("DebugConstGlobalVariable", [&]() {
@@ -4594,7 +4595,7 @@ void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD, const APValue &Init) {
 
 void CGDebugInfo::EmitExternalVariable(llvm::GlobalVariable *Var,
                                        const VarDecl *D) {
-  assert(DebugKind >= codegenoptions::LimitedDebugInfo);
+  assert(CGM.getCodeGenOpts().hasReducedDebugInfo());
   if (D->hasAttr<NoDebugAttr>())
     return;
 
@@ -4619,7 +4620,7 @@ llvm::DIScope *CGDebugInfo::getCurrentContextDescriptor(const Decl *D) {
 }
 
 void CGDebugInfo::EmitUsingDirective(const UsingDirectiveDecl &UD) {
-  if (CGM.getCodeGenOpts().getDebugInfo() < codegenoptions::LimitedDebugInfo)
+  if (!CGM.getCodeGenOpts().hasReducedDebugInfo())
     return;
   const NamespaceDecl *NSDecl = UD.getNominatedNamespace();
   if (!NSDecl->isAnonymousNamespace() ||
@@ -4632,7 +4633,7 @@ void CGDebugInfo::EmitUsingDirective(const UsingDirectiveDecl &UD) {
 }
 
 void CGDebugInfo::EmitUsingDecl(const UsingDecl &UD) {
-  if (CGM.getCodeGenOpts().getDebugInfo() < codegenoptions::LimitedDebugInfo)
+  if (!CGM.getCodeGenOpts().hasReducedDebugInfo())
     return;
   assert(UD.shadow_size() &&
          "We shouldn't be codegening an invalid UsingDecl containing no decls");
@@ -4673,7 +4674,7 @@ void CGDebugInfo::EmitImportDecl(const ImportDecl &ID) {
 
 llvm::DIImportedEntity *
 CGDebugInfo::EmitNamespaceAlias(const NamespaceAliasDecl &NA) {
-  if (CGM.getCodeGenOpts().getDebugInfo() < codegenoptions::LimitedDebugInfo)
+  if (!CGM.getCodeGenOpts().hasReducedDebugInfo())
     return nullptr;
   auto &VH = NamespaceAliasCache[&NA];
   if (VH)
@@ -4795,7 +4796,7 @@ void CGDebugInfo::finalize() {
 }
 
 void CGDebugInfo::EmitExplicitCastType(QualType Ty) {
-  if (CGM.getCodeGenOpts().getDebugInfo() < codegenoptions::LimitedDebugInfo)
+  if (!CGM.getCodeGenOpts().hasReducedDebugInfo())
     return;
 
   if (auto *DieTy = getOrCreateType(Ty, TheCU->getFile()))

clang/lib/CodeGen/CGDecl.cpp

@@ -446,8 +446,7 @@ void CodeGenFunction::EmitStaticVarDecl(const VarDecl &D,
 
   // Emit global variable debug descriptor for static vars.
   CGDebugInfo *DI = getDebugInfo();
-  if (DI &&
+  if (DI && CGM.getCodeGenOpts().hasReducedDebugInfo()) {
-      CGM.getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo) {
     DI->setLocation(D.getLocation());
     DI->EmitGlobalVariable(var, &D);
   }
@@ -1394,8 +1393,7 @@ CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
     EmitVariablyModifiedType(Ty);
 
   auto *DI = getDebugInfo();
-  bool EmitDebugInfo = DI && CGM.getCodeGenOpts().getDebugInfo() >=
+  bool EmitDebugInfo = DI && CGM.getCodeGenOpts().hasReducedDebugInfo();
-                                 codegenoptions::LimitedDebugInfo;
 
   Address address = Address::invalid();
   Address AllocaAddr = Address::invalid();
@@ -2496,9 +2494,7 @@ void CodeGenFunction::EmitParmDecl(const VarDecl &D, ParamValue Arg,
 
   // Emit debug info for param declarations in non-thunk functions.
   if (CGDebugInfo *DI = getDebugInfo()) {
-    if (CGM.getCodeGenOpts().getDebugInfo() >=
+    if (CGM.getCodeGenOpts().hasReducedDebugInfo() && !CurFuncIsThunk) {
-            codegenoptions::LimitedDebugInfo &&
-        !CurFuncIsThunk) {
       DI->EmitDeclareOfArgVariable(&D, DeclPtr.getPointer(), ArgNo, Builder);
     }
   }

clang/lib/CodeGen/CGStmt.cpp

@@ -562,8 +562,7 @@ void CodeGenFunction::EmitLabel(const LabelDecl *D) {
 
   // Emit debug info for labels.
   if (CGDebugInfo *DI = getDebugInfo()) {
-    if (CGM.getCodeGenOpts().getDebugInfo() >=
+    if (CGM.getCodeGenOpts().hasReducedDebugInfo()) {
-        codegenoptions::LimitedDebugInfo) {
       DI->setLocation(D->getLocation());
       DI->EmitLabel(D, Builder);
     }

clang/lib/CodeGen/CGStmtOpenMP.cpp

@@ -567,8 +567,7 @@ CodeGenFunction::GenerateOpenMPCapturedStmtFunction(const CapturedStmt &S) {
   const CapturedDecl *CD = S.getCapturedDecl();
   // Build the argument list.
   bool NeedWrapperFunction =
-      getDebugInfo() &&
+      getDebugInfo() && CGM.getCodeGenOpts().hasReducedDebugInfo();
-      CGM.getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo;
   FunctionArgList Args;
   llvm::MapVector<const Decl *, std::pair<const VarDecl *, Address>> LocalAddrs;
   llvm::DenseMap<const Decl *, std::pair<const Expr *, llvm::Value *>> VLASizes;

clang/lib/CodeGen/CodeGenFunction.cpp

@@ -2110,7 +2110,7 @@ void CodeGenFunction::EmitDeclRefExprDbgValue(const DeclRefExpr *E,
                                               const APValue &Init) {
   assert(Init.hasValue() && "Invalid DeclRefExpr initializer!");
   if (CGDebugInfo *Dbg = getDebugInfo())
-    if (CGM.getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo)
+    if (CGM.getCodeGenOpts().hasReducedDebugInfo())
       Dbg->EmitGlobalVariable(E->getDecl(), Init);
 }
 

clang/lib/CodeGen/CodeGenModule.cpp

@@ -4118,13 +4118,13 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
 
   // Emit global variable debug information.
   if (CGDebugInfo *DI = getModuleDebugInfo())
-    if (getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo)
+    if (getCodeGenOpts().hasReducedDebugInfo())
       DI->EmitGlobalVariable(GV, D);
 }
 
 void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) {
   if (CGDebugInfo *DI = getModuleDebugInfo())
-    if (getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo) {
+    if (getCodeGenOpts().hasReducedDebugInfo()) {
       QualType ASTTy = D->getType();
       llvm::Type *Ty = getTypes().ConvertTypeForMem(D->getType());
       llvm::PointerType *PTy =
@@ -5371,7 +5371,7 @@ void CodeGenModule::EmitTopLevelDecl(Decl *D) {
     ObjCRuntime->GenerateClass(OMD);
     // Emit global variable debug information.
     if (CGDebugInfo *DI = getModuleDebugInfo())
-      if (getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo)
+      if (getCodeGenOpts().hasReducedDebugInfo())
         DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType(
             OMD->getClassInterface()), OMD->getLocation());
     break;

clang/lib/Driver/ToolChains/Clang.cpp

@@ -999,6 +999,9 @@ static void RenderDebugEnablingArgs(const ArgList &Args, ArgStringList &CmdArgs,
   case codegenoptions::DebugLineTablesOnly:
     CmdArgs.push_back("-debug-info-kind=line-tables-only");
     break;
+  case codegenoptions::DebugInfoConstructor:
+    CmdArgs.push_back("-debug-info-kind=constructor");
+    break;
   case codegenoptions::LimitedDebugInfo:
     CmdArgs.push_back("-debug-info-kind=limited");
     break;

clang/lib/Frontend/CompilerInvocation.cpp

@@ -731,6 +731,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
         llvm::StringSwitch<unsigned>(A->getValue())
             .Case("line-tables-only", codegenoptions::DebugLineTablesOnly)
             .Case("line-directives-only", codegenoptions::DebugDirectivesOnly)
+            .Case("constructor", codegenoptions::DebugInfoConstructor)
             .Case("limited", codegenoptions::LimitedDebugInfo)
             .Case("standalone", codegenoptions::FullDebugInfo)
             .Default(~0U);
@@ -787,8 +788,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
       llvm::Triple::arm, llvm::Triple::armeb};
 
   llvm::Triple T(TargetOpts.Triple);
-  if (Opts.OptimizationLevel > 0 &&
+  if (Opts.OptimizationLevel > 0 && Opts.hasReducedDebugInfo() &&
-      Opts.getDebugInfo() >= codegenoptions::LimitedDebugInfo &&
       llvm::is_contained(DebugEntryValueArchs, T.getArch()))
     Opts.EnableDebugEntryValues = Args.hasArg(OPT_femit_debug_entry_values);