make -ftime-trace also trace time spent creating debug info

[llunak]

Summary

In debug builds a noticeable time can be spent generating debug info, so make -ftime-trace track that too.

[anton-afanasyev]

LGTM, thanks!

clang/lib/CodeGen/CGDebugInfo.cpp

 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/Metadata.h"
 #include "llvm/IR/Module.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/MD5.h"
 #include "llvm/Support/Path.h"
+#include "llvm/Support/TimeProfiler.h"
 using namespace clang;
 using namespace clang::CodeGen;
 
 static uint32_t getTypeAlignIfRequired(const Type *Ty, const ASTContext &Ctx) {
   auto TI = Ctx.getTypeInfo(Ty);
   return TI.AlignIsRequired ? TI.Align : 0;
 }
 
void CGDebugInfo::completeUnusedClass(const CXXRecordDecl &D) {
   // it is retained
   RetainedTypes.push_back(CGM.getContext().getRecordType(&D).getAsOpaquePtr());
 }
 
 llvm::DIType *CGDebugInfo::getOrCreateType(QualType Ty, llvm::DIFile *Unit) {
   if (Ty.isNull())
     return nullptr;
 
+  llvm::TimeTraceScope TimeScope("DebugType", [&]() {
+    std::string Name;
+    llvm::raw_string_ostream OS(Name);
+    Ty.print(OS, getPrintingPolicy());
+    return Name;
+  });
+
   // Unwrap the type as needed for debug information.
   Ty = UnwrapTypeForDebugInfo(Ty, CGM.getContext());
 
   if (auto *T = getTypeOrNull(Ty))
     return T;
 
   llvm::DIType *Res = CreateTypeNode(Ty, Unit);
   void *TyPtr = Ty.getAsOpaquePtr();
void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
                                    QualType FnType, llvm::Function *Fn) {
   StringRef Name;
   StringRef LinkageName;
 
   const Decl *D = GD.getDecl();
   if (!D)
     return;
 
+  llvm::TimeTraceScope TimeScope("DebugFunction", [&]() {
+    std::string Name;
+    llvm::raw_string_ostream OS(Name);
+    if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
+      ND->getNameForDiagnostic(OS, getPrintingPolicy(),
+                               /*Qualified=*/true);
+    return Name;
+  });
+
   llvm::DINode::DIFlags Flags = llvm::DINode::FlagZero;
   llvm::DIFile *Unit = getOrCreateFile(Loc);
   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.

 }
 
 void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
                                      const VarDecl *D) {
   assert(DebugKind >= codegenoptions::LimitedDebugInfo);
   if (D->hasAttr<NoDebugAttr>())
     return;
 
+  llvm::TimeTraceScope TimeScope("DebugGlobalVariable", [&]() {
+    std::string Name;
+    llvm::raw_string_ostream OS(Name);
+    D->getNameForDiagnostic(OS, getPrintingPolicy(),
+                            /*Qualified=*/true);
+    return Name;
+  });
+
   // If we already created a DIGlobalVariable for this declaration, just attach
   // it to the llvm::GlobalVariable.
   auto Cached = DeclCache.find(D->getCanonicalDecl());
   if (Cached != DeclCache.end())
     return Var->addDebugInfo(
         cast<llvm::DIGlobalVariableExpression>(Cached->second));
 
   // Create global variable debug descriptor.
void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
   }
   DeclCache[D->getCanonicalDecl()].reset(GVE);
 }
 
 void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD, const APValue &Init) {
   assert(DebugKind >= codegenoptions::LimitedDebugInfo);
   if (VD->hasAttr<NoDebugAttr>())
     return;
+  llvm::TimeTraceScope TimeScope("DebugConstGlobalVariable", [&]() {
+    std::string Name;
+    llvm::raw_string_ostream OS(Name);
+    VD->getNameForDiagnostic(OS, getPrintingPolicy(),
+                             /*Qualified=*/true);
+    return Name;
+  });
+
   auto Align = getDeclAlignIfRequired(VD, CGM.getContext());
   // Create the descriptor for the variable.
   llvm::DIFile *Unit = getOrCreateFile(VD->getLocation());
   StringRef Name = VD->getName();
   llvm::DIType *Ty = getOrCreateType(VD->getType(), Unit);
 
   if (const auto *ECD = dyn_cast<EnumConstantDecl>(VD)) {
     const auto *ED = cast<EnumDecl>(ECD->getDeclContext());