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

62 files changed, 229 insertions, 157 deletions

diff --git a/llvm/include/llvm/DebugInfo/PDB/IPDBSession.h b/llvm/include/llvm/DebugInfo/PDB/IPDBSession.h
index 929c70a7997..64b7665befd 100644
--- a/llvm/include/llvm/DebugInfo/PDB/IPDBSession.h
+++ b/llvm/include/llvm/DebugInfo/PDB/IPDBSession.h
@@ -10,6 +10,7 @@
 #ifndef LLVM_DEBUGINFO_PDB_IPDBSESSION_H
 #define LLVM_DEBUGINFO_PDB_IPDBSESSION_H
 
+#include "PDBSymbol.h"
 #include "PDBTypes.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Casting.h"
@@ -44,6 +45,12 @@ public:
     return std::unique_ptr<T>(ConcreteSymbol);
   }
 
+  template <>
+  std::unique_ptr<PDBSymbol>
+  getConcreteSymbolById<PDBSymbol>(uint32_t SymbolId) const {
+    return getSymbolById(SymbolId);
+  }
+
   virtual std::unique_ptr<PDBSymbol>
   findSymbolByAddress(uint64_t Address, PDB_SymType Type) const = 0;
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbol.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbol.h
index bf511880654..e85d22875cb 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbol.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbol.h
@@ -22,6 +22,23 @@
     return RawSymbol->MethodName();                                            \
   }
 
+#define FORWARD_CONCRETE_SYMBOL_ID_METHOD_WITH_NAME(ConcreteType, PrivateName, \
+                                                    PublicName)                \
+  auto PublicName##Id() const->decltype(RawSymbol->PrivateName##Id()) {        \
+    return RawSymbol->PrivateName##Id();                                       \
+  }                                                                            \
+  std::unique_ptr<ConcreteType> PublicName() const {                           \
+    uint32_t Id = PublicName##Id();                                            \
+    return getConcreteSymbolByIdHelper<ConcreteType>(Id);                      \
+  }
+
+#define FORWARD_SYMBOL_ID_METHOD_WITH_NAME(PrivateName, PublicName)            \
+  FORWARD_CONCRETE_SYMBOL_ID_METHOD_WITH_NAME(PDBSymbol, PrivateName,          \
+                                              PublicName)
+
+#define FORWARD_SYMBOL_ID_METHOD(MethodName)                                   \
+  FORWARD_SYMBOL_ID_METHOD_WITH_NAME(MethodName, MethodName)
+
 namespace llvm {
 
 class StringRef;
@@ -29,6 +46,7 @@ class raw_ostream;
 
 namespace pdb {
 class IPDBRawSymbol;
+class IPDBSession;
 
 #define DECLARE_PDB_SYMBOL_CONCRETE_TYPE(TagValue)                             \
   static const PDB_SymType Tag = TagValue;                                     \
@@ -57,6 +75,8 @@ public:
   /// override the behavior to only dump known fields.
   virtual void dump(PDBSymDumper &Dumper) const = 0;
   void defaultDump(raw_ostream &OS, int Indent) const;
+  void dumpProperties() const;
+  void dumpChildStats() const;
 
   PDB_SymType getSymTag() const;
   uint32_t getSymIndexId() const;
@@ -66,6 +86,14 @@ public:
     return Enumerator->getNext();
   }
 
+  template <typename T> T *cast() { return llvm::dyn_cast<T>(this); }
+
+  template <typename T> const T *cast() const {
+    return llvm::dyn_cast<T>(this);
+  }
+
+  std::unique_ptr<PDBSymbol> clone() const;
+
   template <typename T>
   std::unique_ptr<ConcreteSymbolEnumerator<T>> findAllChildren() const {
     auto BaseIter = RawSymbol->findChildren(T::Tag);
@@ -91,6 +119,20 @@ public:
   std::unique_ptr<IPDBEnumSymbols> getChildStats(TagStats &Stats) const;
 
 protected:
+  std::unique_ptr<PDBSymbol> getSymbolByIdHelper(uint32_t Id) const;
+
+  template <typename ConcreteType>
+  std::unique_ptr<ConcreteType> getConcreteSymbolByIdHelper(uint32_t Id) const {
+    auto Sym = getSymbolByIdHelper(Id);
+    if (!Sym)
+      return nullptr;
+    ConcreteType *Result = Sym->cast<ConcreteType>();
+    if (!Result)
+      return nullptr;
+    Sym.release();
+    return std::unique_ptr<ConcreteType>(Result);
+  }
+
   const IPDBSession &Session;
   const std::unique_ptr<IPDBRawSymbol> RawSymbol;
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolBlock.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolBlock.h
index d0ff62ca7c3..d81da1eaa02 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolBlock.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolBlock.h
@@ -30,7 +30,7 @@ public:
   FORWARD_SYMBOL_METHOD(getAddressOffset)
   FORWARD_SYMBOL_METHOD(getAddressSection)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getLocationType)
   FORWARD_SYMBOL_METHOD(getName)
   FORWARD_SYMBOL_METHOD(getRelativeVirtualAddress)
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompiland.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompiland.h
index f1983b3f7bf..26788017cf3 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompiland.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompiland.h
@@ -29,7 +29,7 @@ public:
   void dump(PDBSymDumper &Dumper) const override;
 
   FORWARD_SYMBOL_METHOD(isEditAndContinueEnabled)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getLibraryName)
   FORWARD_SYMBOL_METHOD(getName)
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompilandDetails.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompilandDetails.h
index bb4a78f68e2..dba50c42cf8 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompilandDetails.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompilandDetails.h
@@ -46,7 +46,7 @@ public:
   FORWARD_SYMBOL_METHOD(isLTCG)
   FORWARD_SYMBOL_METHOD(isMSILNetmodule)
   FORWARD_SYMBOL_METHOD(getLanguage)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getPlatform)
   FORWARD_SYMBOL_METHOD(getSourceFileName)
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompilandEnv.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompilandEnv.h
index a71a0ba2df5..7868f045908 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompilandEnv.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolCompilandEnv.h
@@ -26,7 +26,7 @@ public:
 
   void dump(PDBSymDumper &Dumper) const override;
 
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getName)
   std::string getValue() const;
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolData.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolData.h
index 36f32ab51c1..ad4285df4d4 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolData.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolData.h
@@ -26,8 +26,6 @@ public:
 
   DECLARE_PDB_SYMBOL_CONCRETE_TYPE(PDB_SymType::Data)
 
-  std::unique_ptr<PDBSymbol> getType() const;
-
   void dump(PDBSymDumper &Dumper) const override;
 
   FORWARD_SYMBOL_METHOD(getAccess)
@@ -35,14 +33,14 @@ public:
   FORWARD_SYMBOL_METHOD(getAddressSection)
   FORWARD_SYMBOL_METHOD(getAddressTaken)
   FORWARD_SYMBOL_METHOD(getBitPosition)
-  FORWARD_SYMBOL_METHOD(getClassParentId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
   FORWARD_SYMBOL_METHOD(isCompilerGenerated)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(getDataKind)
   FORWARD_SYMBOL_METHOD(isAggregated)
   FORWARD_SYMBOL_METHOD(isSplitted)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getLocationType)
   FORWARD_SYMBOL_METHOD(getName)
   FORWARD_SYMBOL_METHOD(getOffset)
@@ -50,7 +48,7 @@ public:
   FORWARD_SYMBOL_METHOD(getRelativeVirtualAddress)
   FORWARD_SYMBOL_METHOD(getSlot)
   FORWARD_SYMBOL_METHOD(getToken)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getType)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(getValue)
   FORWARD_SYMBOL_METHOD(getVirtualAddress)
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFunc.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFunc.h
index 7170bcbe846..5686f8716a0 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFunc.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFunc.h
@@ -11,6 +11,7 @@
 #define LLVM_DEBUGINFO_PDB_PDBSYMBOLFUNC_H
 
 #include "PDBSymbol.h"
+#include "PDBSymbolTypeFunctionSig.h"
 #include "PDBTypes.h"
 
 namespace llvm {
@@ -26,8 +27,6 @@ public:
 
   void dump(PDBSymDumper &Dumper) const override;
 
-  std::unique_ptr<PDBSymbolTypeFunctionSig> getSignature() const;
-  std::unique_ptr<PDBSymbolTypeUDT> getClassParent() const;
   std::unique_ptr<IPDBEnumChildren<PDBSymbolData>> getArguments() const;
 
   DECLARE_PDB_SYMBOL_CONCRETE_TYPE(PDB_SymType::Function)
@@ -35,7 +34,7 @@ public:
   FORWARD_SYMBOL_METHOD(getAccess)
   FORWARD_SYMBOL_METHOD(getAddressOffset)
   FORWARD_SYMBOL_METHOD(getAddressSection)
-  FORWARD_SYMBOL_METHOD(getClassParentId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
   FORWARD_SYMBOL_METHOD(isCompilerGenerated)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(hasCustomCallingConvention)
@@ -54,7 +53,7 @@ public:
   FORWARD_SYMBOL_METHOD(isNaked)
   FORWARD_SYMBOL_METHOD(isStatic)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getLocalBasePointerRegisterId)
   FORWARD_SYMBOL_METHOD(getLocationType)
   FORWARD_SYMBOL_METHOD(getName)
@@ -67,7 +66,8 @@ public:
   FORWARD_SYMBOL_METHOD(isPureVirtual)
   FORWARD_SYMBOL_METHOD(getRelativeVirtualAddress)
   FORWARD_SYMBOL_METHOD(getToken)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_CONCRETE_SYMBOL_ID_METHOD_WITH_NAME(PDBSymbolTypeFunctionSig, getType,
+                                              getSignature)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(getUndecoratedName)
   FORWARD_SYMBOL_METHOD(isVirtual)
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFuncDebugEnd.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFuncDebugEnd.h
index 464389503be..3341bd9b30f 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFuncDebugEnd.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFuncDebugEnd.h
@@ -34,7 +34,7 @@ public:
   FORWARD_SYMBOL_METHOD(hasFarReturn)
   FORWARD_SYMBOL_METHOD(hasInterruptReturn)
   FORWARD_SYMBOL_METHOD(isStatic)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getLocationType)
   FORWARD_SYMBOL_METHOD(hasNoInlineAttribute)
   FORWARD_SYMBOL_METHOD(hasNoReturnAttribute)
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFuncDebugStart.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFuncDebugStart.h
index c2e3dd39be6..6729838597c 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFuncDebugStart.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolFuncDebugStart.h
@@ -33,7 +33,7 @@ public:
   FORWARD_SYMBOL_METHOD(hasFarReturn)
   FORWARD_SYMBOL_METHOD(hasInterruptReturn)
   FORWARD_SYMBOL_METHOD(isStatic)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getLocationType)
   FORWARD_SYMBOL_METHOD(hasNoInlineAttribute)
   FORWARD_SYMBOL_METHOD(hasNoReturnAttribute)
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolLabel.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolLabel.h
index 3aeae10b47b..c2b1c28c929 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolLabel.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolLabel.h
@@ -32,7 +32,7 @@ public:
   FORWARD_SYMBOL_METHOD(hasCustomCallingConvention)
   FORWARD_SYMBOL_METHOD(hasFarReturn)
   FORWARD_SYMBOL_METHOD(hasInterruptReturn)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getLocationType)
   FORWARD_SYMBOL_METHOD(getName)
   FORWARD_SYMBOL_METHOD(hasNoInlineAttribute)
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolPublicSymbol.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolPublicSymbol.h
index be073444597..c9e6ee67c57 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolPublicSymbol.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolPublicSymbol.h
@@ -32,7 +32,7 @@ public:
   FORWARD_SYMBOL_METHOD(isCode)
   FORWARD_SYMBOL_METHOD(isFunction)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getLocationType)
   FORWARD_SYMBOL_METHOD(isManagedCode)
   FORWARD_SYMBOL_METHOD(isMSILCode)
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolThunk.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolThunk.h
index 63f7a09fc88..614fad86caa 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolThunk.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolThunk.h
@@ -30,12 +30,12 @@ public:
   FORWARD_SYMBOL_METHOD(getAccess)
   FORWARD_SYMBOL_METHOD(getAddressOffset)
   FORWARD_SYMBOL_METHOD(getAddressSection)
-  FORWARD_SYMBOL_METHOD(getClassParentId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(isIntroVirtualFunction)
   FORWARD_SYMBOL_METHOD(isStatic)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getName)
   FORWARD_SYMBOL_METHOD(isPureVirtual)
   FORWARD_SYMBOL_METHOD(getRelativeVirtualAddress)
@@ -44,7 +44,7 @@ public:
   FORWARD_SYMBOL_METHOD(getTargetVirtualAddress)
   FORWARD_SYMBOL_METHOD(getTargetSection)
   FORWARD_SYMBOL_METHOD(getThunkOrdinal)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getType)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(isVirtual)
   FORWARD_SYMBOL_METHOD(getVirtualAddress)
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeArray.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeArray.h
index 57db03661fb..b70d0e852d9 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeArray.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeArray.h
@@ -25,17 +25,15 @@ public:
 
   DECLARE_PDB_SYMBOL_CONCRETE_TYPE(PDB_SymType::ArrayType)
 
-  std::unique_ptr<PDBSymbol> getElementType() const;
-
   void dump(PDBSymDumper &Dumper) const override;
 
-  FORWARD_SYMBOL_METHOD(getArrayIndexTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getArrayIndexType)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(getCount)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getRank)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD_WITH_NAME(getType, getElementType)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeBaseClass.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeBaseClass.h
index aaa3ab7988d..0924efb8aa9 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeBaseClass.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeBaseClass.h
@@ -28,7 +28,7 @@ public:
   void dump(PDBSymDumper &Dumper) const override;
 
   FORWARD_SYMBOL_METHOD(getAccess)
-  FORWARD_SYMBOL_METHOD(getClassParentId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
   FORWARD_SYMBOL_METHOD(hasConstructor)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(hasAssignmentOperator)
@@ -36,14 +36,14 @@ public:
   FORWARD_SYMBOL_METHOD(hasNestedTypes)
   FORWARD_SYMBOL_METHOD(isIndirectVirtualBaseClass)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getName)
   FORWARD_SYMBOL_METHOD(isNested)
   FORWARD_SYMBOL_METHOD(getOffset)
   FORWARD_SYMBOL_METHOD(hasOverloadedOperator)
   FORWARD_SYMBOL_METHOD(isPacked)
   FORWARD_SYMBOL_METHOD(isScoped)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getType)
   FORWARD_SYMBOL_METHOD(getUdtKind)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
 
@@ -51,7 +51,7 @@ public:
   FORWARD_SYMBOL_METHOD(getVirtualBaseDispIndex)
   FORWARD_SYMBOL_METHOD(getVirtualBasePointerOffset)
   // FORWARD_SYMBOL_METHOD(getVirtualBaseTableType)
-  FORWARD_SYMBOL_METHOD(getVirtualTableShapeId)
+  FORWARD_SYMBOL_ID_METHOD(getVirtualTableShape)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeBuiltin.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeBuiltin.h
index c8f59f1f140..5b1863c42a0 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeBuiltin.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeBuiltin.h
@@ -30,7 +30,7 @@ public:
   FORWARD_SYMBOL_METHOD(getBuiltinType)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeEnum.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeEnum.h
index ade2887bac1..c5ae3c51162 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeEnum.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeEnum.h
@@ -11,6 +11,7 @@
 #define LLVM_DEBUGINFO_PDB_PDBSYMBOLTYPEENUM_H
 
 #include "PDBSymbol.h"
+#include "PDBSymbolTypeBuiltin.h"
 #include "PDBTypes.h"
 
 namespace llvm {
@@ -27,25 +28,22 @@ public:
 
   void dump(PDBSymDumper &Dumper) const override;
 
-  std::unique_ptr<PDBSymbolTypeUDT> getClassParent() const;
-  std::unique_ptr<PDBSymbolTypeBuiltin> getUnderlyingType() const;
-
   FORWARD_SYMBOL_METHOD(getBuiltinType)
-  FORWARD_SYMBOL_METHOD(getClassParentId)
-  FORWARD_SYMBOL_METHOD(getUnmodifiedTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
   FORWARD_SYMBOL_METHOD(hasConstructor)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(hasAssignmentOperator)
   FORWARD_SYMBOL_METHOD(hasCastOperator)
   FORWARD_SYMBOL_METHOD(hasNestedTypes)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getName)
   FORWARD_SYMBOL_METHOD(isNested)
   FORWARD_SYMBOL_METHOD(hasOverloadedOperator)
   FORWARD_SYMBOL_METHOD(isPacked)
   FORWARD_SYMBOL_METHOD(isScoped)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_CONCRETE_SYMBOL_ID_METHOD_WITH_NAME(PDBSymbolTypeBuiltin, getType,
+                                              getUnderlyingType)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFriend.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFriend.h
index 196d149ed2a..24c13128111 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFriend.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFriend.h
@@ -27,9 +27,9 @@ public:
 
   void dump(PDBSymDumper &Dumper) const override;
 
-  FORWARD_SYMBOL_METHOD(getClassParentId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
   FORWARD_SYMBOL_METHOD(getName)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getType)
 };
 
 } // namespace llvm
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFunctionArg.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFunctionArg.h
index 5561341d7e7..3855999c473 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFunctionArg.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFunctionArg.h
@@ -27,9 +27,9 @@ public:
 
   void dump(PDBSymDumper &Dumper) const override;
 
-  FORWARD_SYMBOL_METHOD(getClassParentId)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
+  FORWARD_SYMBOL_ID_METHOD(getType)
 };
 
 } // namespace llvm
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFunctionSig.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFunctionSig.h
index 516011ff8b3..a716cd324b7 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFunctionSig.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeFunctionSig.h
@@ -25,22 +25,20 @@ public:
 
   DECLARE_PDB_SYMBOL_CONCRETE_TYPE(PDB_SymType::FunctionSig)
 
-  std::unique_ptr<PDBSymbol> getReturnType() const;
   std::unique_ptr<IPDBEnumSymbols> getArguments() const;
-  std::unique_ptr<PDBSymbol> getClassParent() const;
 
   void dump(PDBSymDumper &Dumper) const override;
   void dumpArgList(raw_ostream &OS) const;
 
   FORWARD_SYMBOL_METHOD(getCallingConvention)
-  FORWARD_SYMBOL_METHOD(getClassParentId)
-  FORWARD_SYMBOL_METHOD(getUnmodifiedTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
+  FORWARD_SYMBOL_ID_METHOD(getUnmodifiedType)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(getCount)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   // FORWARD_SYMBOL_METHOD(getObjectPointerType)
   FORWARD_SYMBOL_METHOD(getThisAdjust)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD_WITH_NAME(getType, getReturnType)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypePointer.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypePointer.h
index 7a57272adb7..47cfc8a34db 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypePointer.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypePointer.h
@@ -25,15 +25,13 @@ public:
 
   DECLARE_PDB_SYMBOL_CONCRETE_TYPE(PDB_SymType::PointerType)
 
-  std::unique_ptr<PDBSymbol> getPointeeType() const;
-
   void dump(PDBSymDumper &Dumper) const override;
 
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(isReference)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD_WITH_NAME(getType, getPointeeType)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeTypedef.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeTypedef.h
index 5ed4f8d21d9..16c1d1b88c6 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeTypedef.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeTypedef.h
@@ -28,24 +28,24 @@ public:
   void dump(PDBSymDumper &Dumper) const override;
 
   FORWARD_SYMBOL_METHOD(getBuiltinType)
-  FORWARD_SYMBOL_METHOD(getClassParentId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
   FORWARD_SYMBOL_METHOD(hasConstructor)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(hasAssignmentOperator)
   FORWARD_SYMBOL_METHOD(hasCastOperator)
   FORWARD_SYMBOL_METHOD(hasNestedTypes)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getName)
   FORWARD_SYMBOL_METHOD(isNested)
   FORWARD_SYMBOL_METHOD(hasOverloadedOperator)
   FORWARD_SYMBOL_METHOD(isPacked)
   FORWARD_SYMBOL_METHOD(isReference)
   FORWARD_SYMBOL_METHOD(isScoped)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getType)
   FORWARD_SYMBOL_METHOD(getUdtKind)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
-  FORWARD_SYMBOL_METHOD(getVirtualTableShapeId)
+  FORWARD_SYMBOL_ID_METHOD(getVirtualTableShape)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeUDT.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeUDT.h
index 1874dfef34f..47a4525a47b 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeUDT.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeUDT.h
@@ -27,15 +27,15 @@ public:
 
   void dump(PDBSymDumper &Dumper) const override;
 
-  FORWARD_SYMBOL_METHOD(getClassParentId)
-  FORWARD_SYMBOL_METHOD(getUnmodifiedTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
+  FORWARD_SYMBOL_ID_METHOD(getUnmodifiedType)
   FORWARD_SYMBOL_METHOD(hasConstructor)
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(hasAssignmentOperator)
   FORWARD_SYMBOL_METHOD(hasCastOperator)
   FORWARD_SYMBOL_METHOD(hasNestedTypes)
   FORWARD_SYMBOL_METHOD(getLength)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getName)
   FORWARD_SYMBOL_METHOD(isNested)
   FORWARD_SYMBOL_METHOD(hasOverloadedOperator)
@@ -43,7 +43,7 @@ public:
   FORWARD_SYMBOL_METHOD(isScoped)
   FORWARD_SYMBOL_METHOD(getUdtKind)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
-  FORWARD_SYMBOL_METHOD(getVirtualTableShapeId)
+  FORWARD_SYMBOL_ID_METHOD(getVirtualTableShape)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
 }
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeVTable.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeVTable.h
index baf7ab79d60..17612ff4606 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeVTable.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeVTable.h
@@ -27,10 +27,10 @@ public:
 
   void dump(PDBSymDumper &Dumper) const override;
 
-  FORWARD_SYMBOL_METHOD(getClassParentId)
+  FORWARD_SYMBOL_ID_METHOD(getClassParent)
   FORWARD_SYMBOL_METHOD(isConstType)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
-  FORWARD_SYMBOL_METHOD(getTypeId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
+  FORWARD_SYMBOL_ID_METHOD(getType)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeVTableShape.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeVTableShape.h
index 431fc1ac862..8acaabea5bb 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeVTableShape.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolTypeVTableShape.h
@@ -29,7 +29,7 @@ public:
 
   FORWARD_SYMBOL_METHOD(isConstType)
   FORWARD_SYMBOL_METHOD(getCount)
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(isUnalignedType)
   FORWARD_SYMBOL_METHOD(isVolatileType)
 };
diff --git a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolUsingNamespace.h b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolUsingNamespace.h
index a273fe159c1..70fbd5b84c3 100644
--- a/llvm/include/llvm/DebugInfo/PDB/PDBSymbolUsingNamespace.h
+++ b/llvm/include/llvm/DebugInfo/PDB/PDBSymbolUsingNamespace.h
@@ -27,7 +27,7 @@ public:
 
   void dump(PDBSymDumper &Dumper) const override;
 
-  FORWARD_SYMBOL_METHOD(getLexicalParentId)
+  FORWARD_SYMBOL_ID_METHOD(getLexicalParent)
   FORWARD_SYMBOL_METHOD(getName)
 };
 
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);
diff --git a/llvm/tools/llvm-pdbdump/PrettyClassDefinitionDumper.cpp b/llvm/tools/llvm-pdbdump/PrettyClassDefinitionDumper.cpp
index 333313ee7ef..07e1662c47b 100644
--- a/llvm/tools/llvm-pdbdump/PrettyClassDefinitionDumper.cpp
+++ b/llvm/tools/llvm-pdbdump/PrettyClassDefinitionDumper.cpp
@@ -70,26 +70,24 @@ void ClassDefinitionDumper::start(const PDBSymbolTypeUDT &Class) {
 
     if (opts::pretty::ClassFormat ==
         opts::pretty::ClassDefinitionFormat::LayoutOnly) {
-      if (auto Data = dyn_cast<PDBSymbolData>(Child.get())) {
+      if (auto Data = Child->cast<PDBSymbolData>()) {
         switch (Data->getLocationType()) {
         case PDB_LocType::ThisRel:
         case PDB_LocType::BitField:
           break;
         default:
           // All other types of data field do not occupy any storage (e.g. are
-          // const),
-          // so in layout mode we skip them.
+          // const), so in layout mode we skip them.
           continue;
         }
       } else {
         // Only data symbols affect record layout, so skip any non-data symbols
-        // if
-        // we're in record layout mode.
+        // if we're in record layout mode.
         continue;
       }
     }
 
-    if (auto Func = dyn_cast<PDBSymbolFunc>(Child.get())) {
+    if (auto Func = Child->cast<PDBSymbolFunc>()) {
       if (Func->isCompilerGenerated() && opts::pretty::ExcludeCompilerGenerated)
         continue;
 
diff --git a/llvm/tools/llvm-pdbdump/PrettyFunctionDumper.cpp b/llvm/tools/llvm-pdbdump/PrettyFunctionDumper.cpp
index 2f6ca894fad..0e0da026e56 100644
--- a/llvm/tools/llvm-pdbdump/PrettyFunctionDumper.cpp
+++ b/llvm/tools/llvm-pdbdump/PrettyFunctionDumper.cpp
@@ -195,10 +195,7 @@ void FunctionDumper::start(const PDBSymbolFunc &Symbol, PointerType Pointer) {
 }
 
 void FunctionDumper::dump(const PDBSymbolTypeArray &Symbol) {
-  uint32_t ElementTypeId = Symbol.getTypeId();
-  auto ElementType = Symbol.getSession().getSymbolById(ElementTypeId);
-  if (!ElementType)
-    return;
+  auto ElementType = Symbol.getElementType();
 
   ElementType->dump(*this);
   Printer << "[";
@@ -232,12 +229,11 @@ void FunctionDumper::dump(const PDBSymbolTypeTypedef &Symbol) {
 }
 
 void FunctionDumper::dump(const PDBSymbolTypePointer &Symbol) {
-  uint32_t PointeeId = Symbol.getTypeId();
-  auto PointeeType = Symbol.getSession().getSymbolById(PointeeId);
+  auto PointeeType = Symbol.getPointeeType();
   if (!PointeeType)
     return;
 
-  if (auto FuncSig = dyn_cast<PDBSymbolTypeFunctionSig>(PointeeType.get())) {
+  if (auto FuncSig = PointeeType->cast<PDBSymbolTypeFunctionSig>()) {
     FunctionDumper NestedDumper(Printer);
     PointerType Pointer =
         Symbol.isReference() ? PointerType::Reference : PointerType::Pointer;
diff --git a/llvm/tools/llvm-pdbdump/PrettyTypeDumper.cpp b/llvm/tools/llvm-pdbdump/PrettyTypeDumper.cpp
index 88148fb2074..023806c7cb1 100644
--- a/llvm/tools/llvm-pdbdump/PrettyTypeDumper.cpp
+++ b/llvm/tools/llvm-pdbdump/PrettyTypeDumper.cpp
@@ -66,8 +66,6 @@ void TypeDumper::start(const PDBSymbolExe &Exe) {
 void TypeDumper::dump(const PDBSymbolTypeEnum &Symbol) {
   assert(opts::pretty::Enums);
 
-  if (Symbol.getUnmodifiedTypeId() != 0)
-    return;
   if (Printer.IsTypeExcluded(Symbol.getName()))
     return;
   // Dump member enums when dumping their class definition.
diff --git a/llvm/tools/llvm-pdbdump/PrettyTypedefDumper.cpp b/llvm/tools/llvm-pdbdump/PrettyTypedefDumper.cpp
index c458755cb78..861f7e28b38 100644
--- a/llvm/tools/llvm-pdbdump/PrettyTypedefDumper.cpp
+++ b/llvm/tools/llvm-pdbdump/PrettyTypedefDumper.cpp
@@ -53,11 +53,8 @@ void TypedefDumper::dump(const PDBSymbolTypePointer &Symbol) {
     WithColor(Printer, PDB_ColorItem::Keyword).get() << "const ";
   if (Symbol.isVolatileType())
     WithColor(Printer, PDB_ColorItem::Keyword).get() << "volatile ";
-  uint32_t PointeeId = Symbol.getTypeId();
-  auto PointeeType = Symbol.getSession().getSymbolById(PointeeId);
-  if (!PointeeType)
-    return;
-  if (auto FuncSig = dyn_cast<PDBSymbolTypeFunctionSig>(PointeeType.get())) {
+  auto PointeeType = Symbol.getPointeeType();
+  if (auto FuncSig = PointeeType->cast<PDBSymbolTypeFunctionSig>()) {
     FunctionDumper::PointerType Pointer = FunctionDumper::PointerType::Pointer;
     if (Symbol.isReference())
       Pointer = FunctionDumper::PointerType::Reference;
diff --git a/llvm/tools/llvm-pdbdump/PrettyVariableDumper.cpp b/llvm/tools/llvm-pdbdump/PrettyVariableDumper.cpp
index e1469186ad8..c565fcf0dd8 100644
--- a/llvm/tools/llvm-pdbdump/PrettyVariableDumper.cpp
+++ b/llvm/tools/llvm-pdbdump/PrettyVariableDumper.cpp
@@ -101,7 +101,7 @@ void VariableDumper::dump(const PDBSymbolTypePointer &Symbol) {
   if (!PointeeType)
     return;
 
-  if (auto Func = dyn_cast<PDBSymbolFunc>(PointeeType.get())) {
+  if (auto Func = PointeeType->cast<PDBSymbolFunc>()) {
     FunctionDumper NestedDumper(Printer);
     FunctionDumper::PointerType Pointer =
         Symbol.isReference() ? FunctionDumper::PointerType::Reference
@@ -128,11 +128,11 @@ void VariableDumper::dump(const PDBSymbolTypeUDT &Symbol) {
 
 void VariableDumper::dumpSymbolTypeAndName(const PDBSymbol &Type,
                                            StringRef Name) {
-  if (auto *ArrayType = dyn_cast<PDBSymbolTypeArray>(&Type)) {
+  if (auto *ArrayType = Type.cast<PDBSymbolTypeArray>()) {
     std::string IndexSpec;
     raw_string_ostream IndexStream(IndexSpec);
     std::unique_ptr<PDBSymbol> ElementType = ArrayType->getElementType();
-    while (auto NestedArray = dyn_cast<PDBSymbolTypeArray>(ElementType.get())) {
+    while (auto NestedArray = ElementType->cast<PDBSymbolTypeArray>()) {
       IndexStream << "[";
       IndexStream << NestedArray->getCount();
       IndexStream << "]";
@@ -154,10 +154,9 @@ bool VariableDumper::tryDumpFunctionPointer(const PDBSymbol &Type,
                                             StringRef Name) {
   // Function pointers come across as pointers to function signatures.  But the
   // signature carries no name, so we have to handle this case separately.
-  if (auto *PointerType = dyn_cast<PDBSymbolTypePointer>(&Type)) {
+  if (auto *PointerType = Type.cast<PDBSymbolTypePointer>()) {
     auto PointeeType = PointerType->getPointeeType();
-    if (auto *FunctionSig =
-            dyn_cast<PDBSymbolTypeFunctionSig>(PointeeType.get())) {
+    if (auto *FunctionSig = PointeeType->cast<PDBSymbolTypeFunctionSig>()) {
       FunctionDumper Dumper(Printer);
       FunctionDumper::PointerType PT = FunctionDumper::PointerType::Pointer;
       if (PointerType->isReference())