[llvm-pdbdump] Add guard for null pointers and remove unused code

Summary: This avoids crashing when a user tries to dump a pdb with the `-native` option.

Reviewers: zturner, llvm-commits, rnk

Reviewed By: zturner

Subscribers: mgrang

Differential Revision: https://reviews.llvm.org/D44117

llvm-svn: 326863

4 files changed, 108 insertions, 95 deletions

diff --git a/llvm/tools/llvm-pdbutil/PrettyCompilandDumper.cpp b/llvm/tools/llvm-pdbutil/PrettyCompilandDumper.cpp
index 65e8badbc99..b19b09873be 100644
--- a/llvm/tools/llvm-pdbutil/PrettyCompilandDumper.cpp
+++ b/llvm/tools/llvm-pdbutil/PrettyCompilandDumper.cpp
@@ -55,62 +55,67 @@ void CompilandDumper::start(const PDBSymbolCompiland &Symbol,
 
   if (opts & Flags::Lines) {
     const IPDBSession &Session = Symbol.getSession();
-    auto Files = Session.getSourceFilesForCompiland(Symbol);
-    Printer.Indent();
-    while (auto File = Files->getNext()) {
-      Printer.NewLine();
-      WithColor(Printer, PDB_ColorItem::Path).get() << File->getFileName();
-
-      auto Lines = Session.findLineNumbers(Symbol, *File);
+    if (auto Files = Session.getSourceFilesForCompiland(Symbol)) {
       Printer.Indent();
-      while (auto Line = Lines->getNext()) {
+      while (auto File = Files->getNext()) {
         Printer.NewLine();
-        uint32_t LineStart = Line->getLineNumber();
-        uint32_t LineEnd = Line->getLineNumberEnd();
-
-        Printer << "Line ";
-        PDB_ColorItem StatementColor = Line->isStatement()
-                                           ? PDB_ColorItem::Keyword
-                                           : PDB_ColorItem::LiteralValue;
-        WithColor(Printer, StatementColor).get() << LineStart;
-        if (LineStart != LineEnd)
-          WithColor(Printer, StatementColor).get() << " - " << LineEnd;
-
-        uint32_t ColumnStart = Line->getColumnNumber();
-        uint32_t ColumnEnd = Line->getColumnNumberEnd();
-        if (ColumnStart != 0 || ColumnEnd != 0) {
-          Printer << ", Column: ";
-          WithColor(Printer, StatementColor).get() << ColumnStart;
-          if (ColumnEnd != ColumnStart)
-            WithColor(Printer, StatementColor).get() << " - " << ColumnEnd;
-        }
-
-        Printer << ", Address: ";
-        if (Line->getLength() > 0) {
-          uint64_t AddrStart = Line->getVirtualAddress();
-          uint64_t AddrEnd = AddrStart + Line->getLength() - 1;
-          WithColor(Printer, PDB_ColorItem::Address).get()
+        WithColor(Printer, PDB_ColorItem::Path).get() << File->getFileName();
+
+        auto Lines = Session.findLineNumbers(Symbol, *File);
+        if (!Lines)
+          continue;
+
+        Printer.Indent();
+        while (auto Line = Lines->getNext()) {
+          Printer.NewLine();
+          uint32_t LineStart = Line->getLineNumber();
+          uint32_t LineEnd = Line->getLineNumberEnd();
+
+          Printer << "Line ";
+          PDB_ColorItem StatementColor = Line->isStatement()
+            ? PDB_ColorItem::Keyword
+            : PDB_ColorItem::LiteralValue;
+          WithColor(Printer, StatementColor).get() << LineStart;
+          if (LineStart != LineEnd)
+            WithColor(Printer, StatementColor).get() << " - " << LineEnd;
+
+          uint32_t ColumnStart = Line->getColumnNumber();
+          uint32_t ColumnEnd = Line->getColumnNumberEnd();
+          if (ColumnStart != 0 || ColumnEnd != 0) {
+            Printer << ", Column: ";
+            WithColor(Printer, StatementColor).get() << ColumnStart;
+            if (ColumnEnd != ColumnStart)
+              WithColor(Printer, StatementColor).get() << " - " << ColumnEnd;
+          }
+
+          Printer << ", Address: ";
+          if (Line->getLength() > 0) {
+            uint64_t AddrStart = Line->getVirtualAddress();
+            uint64_t AddrEnd = AddrStart + Line->getLength() - 1;
+            WithColor(Printer, PDB_ColorItem::Address).get()
               << "[" << format_hex(AddrStart, 10) << " - "
               << format_hex(AddrEnd, 10) << "]";
-          Printer << " (" << Line->getLength() << " bytes)";
-        } else {
-          uint64_t AddrStart = Line->getVirtualAddress();
-          WithColor(Printer, PDB_ColorItem::Address).get()
+            Printer << " (" << Line->getLength() << " bytes)";
+          } else {
+            uint64_t AddrStart = Line->getVirtualAddress();
+            WithColor(Printer, PDB_ColorItem::Address).get()
               << "[" << format_hex(AddrStart, 10) << "] ";
-          Printer << "(0 bytes)";
+            Printer << "(0 bytes)";
+          }
         }
+        Printer.Unindent();
       }
       Printer.Unindent();
     }
-    Printer.Unindent();
   }
 
   if (opts & Flags::Children) {
-    auto ChildrenEnum = Symbol.findAllChildren();
-    Printer.Indent();
-    while (auto Child = ChildrenEnum->getNext())
-      Child->dump(*this);
-    Printer.Unindent();
+    if (auto ChildrenEnum = Symbol.findAllChildren()) {
+      Printer.Indent();
+      while (auto Child = ChildrenEnum->getNext())
+        Child->dump(*this);
+      Printer.Unindent();
+    }
   }
 }
 
diff --git a/llvm/tools/llvm-pdbutil/PrettyExternalSymbolDumper.cpp b/llvm/tools/llvm-pdbutil/PrettyExternalSymbolDumper.cpp
index fc40d90cee9..739a95e6342 100644
--- a/llvm/tools/llvm-pdbutil/PrettyExternalSymbolDumper.cpp
+++ b/llvm/tools/llvm-pdbutil/PrettyExternalSymbolDumper.cpp
@@ -21,9 +21,10 @@ ExternalSymbolDumper::ExternalSymbolDumper(LinePrinter &P)
     : PDBSymDumper(true), Printer(P) {}
 
 void ExternalSymbolDumper::start(const PDBSymbolExe &Symbol) {
-  auto Vars = Symbol.findAllChildren<PDBSymbolPublicSymbol>();
-  while (auto Var = Vars->getNext())
-    Var->dump(*this);
+  if (auto Vars = Symbol.findAllChildren<PDBSymbolPublicSymbol>()) {
+    while (auto Var = Vars->getNext())
+      Var->dump(*this);
+  }
 }
 
 void ExternalSymbolDumper::dump(const PDBSymbolPublicSymbol &Symbol) {
diff --git a/llvm/tools/llvm-pdbutil/PrettyTypeDumper.cpp b/llvm/tools/llvm-pdbutil/PrettyTypeDumper.cpp
index 0f6086395ad..5c4c82b5ffe 100644
--- a/llvm/tools/llvm-pdbutil/PrettyTypeDumper.cpp
+++ b/llvm/tools/llvm-pdbutil/PrettyTypeDumper.cpp
@@ -135,7 +135,6 @@ filterAndSortClassDefs(LinePrinter &Printer, Enumerator &E,
 TypeDumper::TypeDumper(LinePrinter &P) : PDBSymDumper(true), Printer(P) {}
 
 void TypeDumper::start(const PDBSymbolExe &Exe) {
-  auto Children = Exe.findAllChildren();
   if (opts::pretty::Enums) {
     if (auto Enums = Exe.findAllChildren<PDBSymbolTypeEnum>()) {
       Printer.NewLine();
diff --git a/llvm/tools/llvm-pdbutil/llvm-pdbutil.cpp b/llvm/tools/llvm-pdbutil/llvm-pdbutil.cpp
index 089f7256536..a2a97596dc9 100644
--- a/llvm/tools/llvm-pdbutil/llvm-pdbutil.cpp
+++ b/llvm/tools/llvm-pdbutil/llvm-pdbutil.cpp
@@ -857,6 +857,8 @@ static void dumpPretty(StringRef Path) {
   LinePrinter Printer(2, UseColor, Stream);
 
   auto GlobalScope(Session->getGlobalScope());
+  if (!GlobalScope)
+    return;
   std::string FileName(GlobalScope->getSymbolsFileName());
 
   WithColor(Printer, PDB_ColorItem::None).get() << "Summary for ";
@@ -893,15 +895,16 @@ static void dumpPretty(StringRef Path) {
     Printer.NewLine();
     WithColor(Printer, PDB_ColorItem::SectionHeader).get()
         << "---COMPILANDS---";
-    Printer.Indent();
-    auto Compilands = GlobalScope->findAllChildren<PDBSymbolCompiland>();
-    CompilandDumper Dumper(Printer);
-    CompilandDumpFlags options = CompilandDumper::Flags::None;
-    if (opts::pretty::Lines)
-      options = options | CompilandDumper::Flags::Lines;
-    while (auto Compiland = Compilands->getNext())
-      Dumper.start(*Compiland, options);
-    Printer.Unindent();
+    if (auto Compilands = GlobalScope->findAllChildren<PDBSymbolCompiland>()) {
+      Printer.Indent();
+      CompilandDumper Dumper(Printer);
+      CompilandDumpFlags options = CompilandDumper::Flags::None;
+      if (opts::pretty::Lines)
+        options = options | CompilandDumper::Flags::Lines;
+      while (auto Compiland = Compilands->getNext())
+        Dumper.start(*Compiland, options);
+      Printer.Unindent();
+    }
   }
 
   if (opts::pretty::Classes || opts::pretty::Enums || opts::pretty::Typedefs) {
@@ -916,12 +919,13 @@ static void dumpPretty(StringRef Path) {
   if (opts::pretty::Symbols) {
     Printer.NewLine();
     WithColor(Printer, PDB_ColorItem::SectionHeader).get() << "---SYMBOLS---";
-    Printer.Indent();
-    auto Compilands = GlobalScope->findAllChildren<PDBSymbolCompiland>();
-    CompilandDumper Dumper(Printer);
-    while (auto Compiland = Compilands->getNext())
-      Dumper.start(*Compiland, true);
-    Printer.Unindent();
+    if (auto Compilands = GlobalScope->findAllChildren<PDBSymbolCompiland>()) {
+      Printer.Indent();
+      CompilandDumper Dumper(Printer);
+      while (auto Compiland = Compilands->getNext())
+        Dumper.start(*Compiland, true);
+      Printer.Unindent();
+    }
   }
 
   if (opts::pretty::Globals) {
@@ -929,45 +933,49 @@ static void dumpPretty(StringRef Path) {
     WithColor(Printer, PDB_ColorItem::SectionHeader).get() << "---GLOBALS---";
     Printer.Indent();
     if (shouldDumpSymLevel(opts::pretty::SymLevel::Functions)) {
-      FunctionDumper Dumper(Printer);
-      auto Functions = GlobalScope->findAllChildren<PDBSymbolFunc>();
-      if (opts::pretty::SymbolOrder == opts::pretty::SymbolSortMode::None) {
-        while (auto Function = Functions->getNext()) {
-          Printer.NewLine();
-          Dumper.start(*Function, FunctionDumper::PointerType::None);
-        }
-      } else {
-        std::vector<std::unique_ptr<PDBSymbolFunc>> Funcs;
-        while (auto Func = Functions->getNext())
-          Funcs.push_back(std::move(Func));
-        std::sort(Funcs.begin(), Funcs.end(),
-                  opts::pretty::compareFunctionSymbols);
-        for (const auto &Func : Funcs) {
-          Printer.NewLine();
-          Dumper.start(*Func, FunctionDumper::PointerType::None);
+      if (auto Functions = GlobalScope->findAllChildren<PDBSymbolFunc>()) {
+        FunctionDumper Dumper(Printer);
+        if (opts::pretty::SymbolOrder == opts::pretty::SymbolSortMode::None) {
+          while (auto Function = Functions->getNext()) {
+            Printer.NewLine();
+            Dumper.start(*Function, FunctionDumper::PointerType::None);
+          }
+        } else {
+          std::vector<std::unique_ptr<PDBSymbolFunc>> Funcs;
+          while (auto Func = Functions->getNext())
+            Funcs.push_back(std::move(Func));
+          std::sort(Funcs.begin(), Funcs.end(),
+                    opts::pretty::compareFunctionSymbols);
+          for (const auto &Func : Funcs) {
+            Printer.NewLine();
+            Dumper.start(*Func, FunctionDumper::PointerType::None);
+          }
         }
       }
     }
     if (shouldDumpSymLevel(opts::pretty::SymLevel::Data)) {
-      auto Vars = GlobalScope->findAllChildren<PDBSymbolData>();
-      VariableDumper Dumper(Printer);
-      if (opts::pretty::SymbolOrder == opts::pretty::SymbolSortMode::None) {
-        while (auto Var = Vars->getNext())
-          Dumper.start(*Var);
-      } else {
-        std::vector<std::unique_ptr<PDBSymbolData>> Datas;
-        while (auto Var = Vars->getNext())
-          Datas.push_back(std::move(Var));
-        std::sort(Datas.begin(), Datas.end(), opts::pretty::compareDataSymbols);
-        for (const auto &Var : Datas)
-          Dumper.start(*Var);
+      if (auto Vars = GlobalScope->findAllChildren<PDBSymbolData>()) {
+        VariableDumper Dumper(Printer);
+        if (opts::pretty::SymbolOrder == opts::pretty::SymbolSortMode::None) {
+          while (auto Var = Vars->getNext())
+            Dumper.start(*Var);
+        } else {
+          std::vector<std::unique_ptr<PDBSymbolData>> Datas;
+          while (auto Var = Vars->getNext())
+            Datas.push_back(std::move(Var));
+          std::sort(Datas.begin(), Datas.end(),
+                    opts::pretty::compareDataSymbols);
+          for (const auto &Var : Datas)
+            Dumper.start(*Var);
+        }
       }
     }
     if (shouldDumpSymLevel(opts::pretty::SymLevel::Thunks)) {
-      auto Thunks = GlobalScope->findAllChildren<PDBSymbolThunk>();
-      CompilandDumper Dumper(Printer);
-      while (auto Thunk = Thunks->getNext())
-        Dumper.dump(*Thunk);
+      if (auto Thunks = GlobalScope->findAllChildren<PDBSymbolThunk>()) {
+        CompilandDumper Dumper(Printer);
+        while (auto Thunk = Thunks->getNext())
+          Dumper.dump(*Thunk);
+      }
     }
     Printer.Unindent();
   }