General usability improvements to generic PDB library.

1. Added some asserts to make sure concrete symbol types don't
   get constructed with RawSymbols that have an incompatible
   SymTag enum value.
2. Added new forwarding macros that auto-define an Id/Sym method
   pair whenever there is a method that returns a SymIndexId.
   Previously we would just provide one method that returned only
   the SymIndexId and it was up to the caller to use the Session
   object to get a pointer to the symbol.  Now we automatically
   get both the method that returns the Id, as well as a method
   that returns the pointer directly with just one macro.
3. Added some methods for dumping straight to stdout that can
   be used from inside the debugger for diagnostics during a
   debug session.
4. Added a clone() method and a cast<T>() method to PDBSymbol
   that can shorten some usage patterns.

llvm-svn: 299831

31 files changed, 110 insertions, 65 deletions

diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbol.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbol.cpp
index 633e11aacf1..2c8438f9c23 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbol.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbol.cpp
@@ -10,6 +10,7 @@
 #include "llvm/DebugInfo/PDB/PDBSymbol.h"
 #include "llvm/DebugInfo/PDB/IPDBEnumChildren.h"
 #include "llvm/DebugInfo/PDB/IPDBRawSymbol.h"
+#include "llvm/DebugInfo/PDB/IPDBSession.h"
 #include "llvm/DebugInfo/PDB/PDBExtras.h"
 #include "llvm/DebugInfo/PDB/PDBSymbolAnnotation.h"
 #include "llvm/DebugInfo/PDB/PDBSymbolBlock.h"
@@ -100,7 +101,7 @@ PDBSymbol::create(const IPDBSession &PDBSession,
 }
 
 #define TRY_DUMP_TYPE(Type)                                                    \
-  if (const Type *DerivedThis = dyn_cast<Type>(this))                          \
+  if (const Type *DerivedThis = this->cast<Type>())                            \
     Dumper.dump(OS, Indent, *DerivedThis);
 
 #define ELSE_TRY_DUMP_TYPE(Type, Dumper) else TRY_DUMP_TYPE(Type, Dumper)
@@ -109,6 +110,26 @@ void PDBSymbol::defaultDump(raw_ostream &OS, int Indent) const {
   RawSymbol->dump(OS, Indent);
 }
 
+void PDBSymbol::dumpProperties() const {
+  outs() << "\n";
+  defaultDump(outs(), 0);
+  outs().flush();
+}
+
+void PDBSymbol::dumpChildStats() const {
+  TagStats Stats;
+  getChildStats(Stats);
+  outs() << "\n";
+  for (auto &Stat : Stats) {
+    outs() << Stat.first << ": " << Stat.second << "\n";
+  }
+  outs().flush();
+}
+
+std::unique_ptr<PDBSymbol> PDBSymbol::clone() const {
+  return Session.getSymbolById(getSymIndexId());
+}
+
 PDB_SymType PDBSymbol::getSymTag() const { return RawSymbol->getSymTag(); }
 uint32_t PDBSymbol::getSymIndexId() const { return RawSymbol->getSymIndexId(); }
 
@@ -148,3 +169,7 @@ PDBSymbol::getChildStats(TagStats &Stats) const {
   Result->reset();
   return Result;
 }
+
+std::unique_ptr<PDBSymbol> PDBSymbol::getSymbolByIdHelper(uint32_t Id) const {
+  return Session.getSymbolById(Id);
+}
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolAnnotation.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolAnnotation.cpp
index cdb167b6191..3648272e1d0 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolAnnotation.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolAnnotation.cpp
@@ -18,7 +18,9 @@ using namespace llvm::pdb;
 
 PDBSymbolAnnotation::PDBSymbolAnnotation(const IPDBSession &PDBSession,
                                          std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Annotation);
+}
 
 void PDBSymbolAnnotation::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolBlock.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolBlock.cpp
index fd5dc9427ab..7385d3ba148 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolBlock.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolBlock.cpp
@@ -19,6 +19,8 @@ using namespace llvm::pdb;
 
 PDBSymbolBlock::PDBSymbolBlock(const IPDBSession &PDBSession,
                                std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Block);
+}
 
 void PDBSymbolBlock::dump(PDBSymDumper &Dumper) const { Dumper.dump(*this); }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolCompiland.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolCompiland.cpp
index ebff08846ca..854cf42d1ba 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolCompiland.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolCompiland.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolCompiland::PDBSymbolCompiland(const IPDBSession &PDBSession,
                                        std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Compiland);
+}
 
 void PDBSymbolCompiland::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolCompilandDetails.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolCompilandDetails.cpp
index 6dbd5228f2c..e08450e0ad0 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolCompilandDetails.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolCompilandDetails.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolCompilandDetails::PDBSymbolCompilandDetails(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::CompilandDetails);
+}
 
 void PDBSymbolCompilandDetails::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolCompilandEnv.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolCompilandEnv.cpp
index 9c7f0b1be56..2f1c43666ae 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolCompilandEnv.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolCompilandEnv.cpp
@@ -20,7 +20,9 @@ using namespace llvm::pdb;
 
 PDBSymbolCompilandEnv::PDBSymbolCompilandEnv(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::CompilandEnv);
+}
 
 std::string PDBSymbolCompilandEnv::getValue() const {
   Variant Value = RawSymbol->getValue();
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolCustom.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolCustom.cpp
index 0ea387a0eab..9ec20bb62d7 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolCustom.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolCustom.cpp
@@ -20,7 +20,9 @@ using namespace llvm::pdb;
 
 PDBSymbolCustom::PDBSymbolCustom(const IPDBSession &PDBSession,
                                  std::unique_ptr<IPDBRawSymbol> CustomSymbol)
-    : PDBSymbol(PDBSession, std::move(CustomSymbol)) {}
+    : PDBSymbol(PDBSession, std::move(CustomSymbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Custom);
+}
 
 void PDBSymbolCustom::getDataBytes(llvm::SmallVector<uint8_t, 32> &bytes) {
   RawSymbol->getDataBytes(bytes);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolData.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolData.cpp
index 62bb6f3f41e..60026689c6f 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolData.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolData.cpp
@@ -19,10 +19,8 @@ using namespace llvm::pdb;
 
 PDBSymbolData::PDBSymbolData(const IPDBSession &PDBSession,
                              std::unique_ptr<IPDBRawSymbol> DataSymbol)
-    : PDBSymbol(PDBSession, std::move(DataSymbol)) {}
-
-std::unique_ptr<PDBSymbol> PDBSymbolData::getType() const {
-  return Session.getSymbolById(getTypeId());
+    : PDBSymbol(PDBSession, std::move(DataSymbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Data);
 }
 
 void PDBSymbolData::dump(PDBSymDumper &Dumper) const { Dumper.dump(*this); }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolExe.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolExe.cpp
index 60101c168a7..b9fcac78c36 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolExe.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolExe.cpp
@@ -18,6 +18,8 @@ using namespace llvm::pdb;
 
 PDBSymbolExe::PDBSymbolExe(const IPDBSession &PDBSession,
                            std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Exe);
+}
 
 void PDBSymbolExe::dump(PDBSymDumper &Dumper) const { Dumper.dump(*this); }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolFunc.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolFunc.cpp
index 35251c0cc1c..3c0bd25ed09 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolFunc.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolFunc.cpp
@@ -85,10 +85,8 @@ private:
 
 PDBSymbolFunc::PDBSymbolFunc(const IPDBSession &PDBSession,
                              std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
-
-std::unique_ptr<PDBSymbolTypeFunctionSig> PDBSymbolFunc::getSignature() const {
-  return Session.getConcreteSymbolById<PDBSymbolTypeFunctionSig>(getTypeId());
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Function);
 }
 
 std::unique_ptr<IPDBEnumChildren<PDBSymbolData>>
@@ -96,8 +94,4 @@ PDBSymbolFunc::getArguments() const {
   return llvm::make_unique<FunctionArgEnumerator>(Session, *this);
 }
 
-std::unique_ptr<PDBSymbolTypeUDT> PDBSymbolFunc::getClassParent() const {
-  return Session.getConcreteSymbolById<PDBSymbolTypeUDT>(getClassParentId());
-}
-
 void PDBSymbolFunc::dump(PDBSymDumper &Dumper) const { Dumper.dump(*this); }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolFuncDebugEnd.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolFuncDebugEnd.cpp
index 77e996f651d..482c95e3a85 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolFuncDebugEnd.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolFuncDebugEnd.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolFuncDebugEnd::PDBSymbolFuncDebugEnd(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::FuncDebugEnd);
+}
 
 void PDBSymbolFuncDebugEnd::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolFuncDebugStart.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolFuncDebugStart.cpp
index 9c653879176..ae23c7619e2 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolFuncDebugStart.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolFuncDebugStart.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolFuncDebugStart::PDBSymbolFuncDebugStart(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::FuncDebugStart);
+}
 
 void PDBSymbolFuncDebugStart::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolLabel.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolLabel.cpp
index d2cfd11c35e..a67a20d8e35 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolLabel.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolLabel.cpp
@@ -18,6 +18,8 @@ using namespace llvm::pdb;
 
 PDBSymbolLabel::PDBSymbolLabel(const IPDBSession &PDBSession,
                                std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Label);
+}
 
 void PDBSymbolLabel::dump(PDBSymDumper &Dumper) const { Dumper.dump(*this); }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolPublicSymbol.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolPublicSymbol.cpp
index 97d66874081..87bb4044216 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolPublicSymbol.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolPublicSymbol.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolPublicSymbol::PDBSymbolPublicSymbol(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::PublicSymbol);
+}
 
 void PDBSymbolPublicSymbol::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolThunk.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolThunk.cpp
index ef8897d12af..b2648197f9c 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolThunk.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolThunk.cpp
@@ -18,6 +18,8 @@ using namespace llvm::pdb;
 
 PDBSymbolThunk::PDBSymbolThunk(const IPDBSession &PDBSession,
                                std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Thunk);
+}
 
 void PDBSymbolThunk::dump(PDBSymDumper &Dumper) const { Dumper.dump(*this); }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeArray.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeArray.cpp
index c010cc5d767..cf9b6fee98d 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeArray.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeArray.cpp
@@ -19,10 +19,8 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeArray::PDBSymbolTypeArray(const IPDBSession &PDBSession,
                                        std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
-
-std::unique_ptr<PDBSymbol> PDBSymbolTypeArray::getElementType() const {
-  return Session.getSymbolById(getTypeId());
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::ArrayType);
 }
 
 void PDBSymbolTypeArray::dump(PDBSymDumper &Dumper) const {
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeBaseClass.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeBaseClass.cpp
index 382c397b24d..0ee18d47162 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeBaseClass.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeBaseClass.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeBaseClass::PDBSymbolTypeBaseClass(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::BaseClass);
+}
 
 void PDBSymbolTypeBaseClass::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeBuiltin.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeBuiltin.cpp
index e5d65bf5d1f..0bf563af7df 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeBuiltin.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeBuiltin.cpp
@@ -18,7 +18,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeBuiltin::PDBSymbolTypeBuiltin(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::BuiltinType);
+}
 
 void PDBSymbolTypeBuiltin::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeCustom.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeCustom.cpp
index 1d80c97f9ed..f617d8d0c2d 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeCustom.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeCustom.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeCustom::PDBSymbolTypeCustom(const IPDBSession &PDBSession,
                                          std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::CustomType);
+}
 
 void PDBSymbolTypeCustom::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeDimension.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeDimension.cpp
index 535d97dcd21..68ba87c1cdf 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeDimension.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeDimension.cpp
@@ -20,7 +20,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeDimension::PDBSymbolTypeDimension(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Dimension);
+}
 
 void PDBSymbolTypeDimension::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeEnum.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeEnum.cpp
index 788f2b732aa..2addea072c8 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeEnum.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeEnum.cpp
@@ -21,15 +21,8 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeEnum::PDBSymbolTypeEnum(const IPDBSession &PDBSession,
                                      std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
-
-std::unique_ptr<PDBSymbolTypeUDT> PDBSymbolTypeEnum::getClassParent() const {
-  return Session.getConcreteSymbolById<PDBSymbolTypeUDT>(getClassParentId());
-}
-
-std::unique_ptr<PDBSymbolTypeBuiltin>
-PDBSymbolTypeEnum::getUnderlyingType() const {
-  return Session.getConcreteSymbolById<PDBSymbolTypeBuiltin>(getTypeId());
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Enum);
 }
 
 void PDBSymbolTypeEnum::dump(PDBSymDumper &Dumper) const { Dumper.dump(*this); }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFriend.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFriend.cpp
index 5831baebb99..ec27985e91d 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFriend.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFriend.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeFriend::PDBSymbolTypeFriend(const IPDBSession &PDBSession,
                                          std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Friend);
+}
 
 void PDBSymbolTypeFriend::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFunctionArg.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFunctionArg.cpp
index c6f586db9e5..4d5cd63f685 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFunctionArg.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFunctionArg.cpp
@@ -18,7 +18,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeFunctionArg::PDBSymbolTypeFunctionArg(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::FunctionArg);
+}
 
 void PDBSymbolTypeFunctionArg::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFunctionSig.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFunctionSig.cpp
index 057ae260885..1d53c7daabf 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFunctionSig.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeFunctionSig.cpp
@@ -68,10 +68,8 @@ private:
 
 PDBSymbolTypeFunctionSig::PDBSymbolTypeFunctionSig(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
-
-std::unique_ptr<PDBSymbol> PDBSymbolTypeFunctionSig::getReturnType() const {
-  return Session.getSymbolById(getTypeId());
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::FunctionSig);
 }
 
 std::unique_ptr<IPDBEnumSymbols>
@@ -79,13 +77,6 @@ PDBSymbolTypeFunctionSig::getArguments() const {
   return llvm::make_unique<FunctionArgEnumerator>(Session, *this);
 }
 
-std::unique_ptr<PDBSymbol> PDBSymbolTypeFunctionSig::getClassParent() const {
-  uint32_t ClassId = getClassParentId();
-  if (ClassId == 0)
-    return nullptr;
-  return Session.getSymbolById(ClassId);
-}
-
 void PDBSymbolTypeFunctionSig::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
 }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeManaged.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeManaged.cpp
index 072d2cfd42f..86e0ec4f856 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeManaged.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeManaged.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeManaged::PDBSymbolTypeManaged(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::ManagedType);
+}
 
 void PDBSymbolTypeManaged::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypePointer.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypePointer.cpp
index 699771450a5..f93b12d11ad 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypePointer.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypePointer.cpp
@@ -19,10 +19,8 @@ using namespace llvm::pdb;
 
 PDBSymbolTypePointer::PDBSymbolTypePointer(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
-
-std::unique_ptr<PDBSymbol> PDBSymbolTypePointer::getPointeeType() const {
-  return Session.getSymbolById(getTypeId());
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::PointerType);
 }
 
 void PDBSymbolTypePointer::dump(PDBSymDumper &Dumper) const {
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeTypedef.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeTypedef.cpp
index 0f283b9e21a..102b540e0fe 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeTypedef.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeTypedef.cpp
@@ -18,7 +18,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeTypedef::PDBSymbolTypeTypedef(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::Typedef);
+}
 
 void PDBSymbolTypeTypedef::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeUDT.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeUDT.cpp
index c71838cc7a6..4a9a9ed5fda 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeUDT.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeUDT.cpp
@@ -18,6 +18,8 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeUDT::PDBSymbolTypeUDT(const IPDBSession &PDBSession,
                                    std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::UDT);
+}
 
 void PDBSymbolTypeUDT::dump(PDBSymDumper &Dumper) const { Dumper.dump(*this); }
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeVTable.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeVTable.cpp
index 6b76db5912c..9a21855f57f 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeVTable.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeVTable.cpp
@@ -18,7 +18,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeVTable::PDBSymbolTypeVTable(const IPDBSession &PDBSession,
                                          std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::VTable);
+}
 
 void PDBSymbolTypeVTable::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeVTableShape.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeVTableShape.cpp
index ef509d64bf6..a516a4d2c42 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolTypeVTableShape.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolTypeVTableShape.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolTypeVTableShape::PDBSymbolTypeVTableShape(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::VTableShape);
+}
 
 void PDBSymbolTypeVTableShape::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolUsingNamespace.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolUsingNamespace.cpp
index 6a62d554f42..020aec9e98a 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolUsingNamespace.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolUsingNamespace.cpp
@@ -19,7 +19,9 @@ using namespace llvm::pdb;
 
 PDBSymbolUsingNamespace::PDBSymbolUsingNamespace(
     const IPDBSession &PDBSession, std::unique_ptr<IPDBRawSymbol> Symbol)
-    : PDBSymbol(PDBSession, std::move(Symbol)) {}
+    : PDBSymbol(PDBSession, std::move(Symbol)) {
+  assert(RawSymbol->getSymTag() == PDB_SymType::UsingNamespace);
+}
 
 void PDBSymbolUsingNamespace::dump(PDBSymDumper &Dumper) const {
   Dumper.dump(*this);