[codeview] Return type indices for typedefs

Use the type index of the underlying type unless we have a typedef from
long to HRESULT; HRESULT typedefs are translated to T_HRESULT.

llvm-svn: 271494

2 files changed, 13 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index dec6770537e..7c167ba0c43 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -731,6 +731,8 @@ void CodeViewDebug::beginFunction(const MachineFunction *MF) {
 TypeIndex CodeViewDebug::lowerType(const DIType *Ty) {
   // Generic dispatch for lowering an unknown type.
   switch (Ty->getTag()) {
+  case dwarf::DW_TAG_typedef:
+    return lowerTypeAlias(cast<DIDerivedType>(Ty));
   case dwarf::DW_TAG_base_type:
     return lowerTypeBasic(cast<DIBasicType>(Ty));
   case dwarf::DW_TAG_pointer_type:
@@ -748,6 +750,16 @@ TypeIndex CodeViewDebug::lowerType(const DIType *Ty) {
   }
 }
 
+TypeIndex CodeViewDebug::lowerTypeAlias(const DIDerivedType *Ty) {
+  // TODO: MSVC emits a S_UDT record.
+  DITypeRef UnderlyingTypeRef = Ty->getBaseType();
+  TypeIndex UnderlyingTypeIndex = getTypeIndex(UnderlyingTypeRef);
+  if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::Int32Long) &&
+      Ty->getName() == "HRESULT")
+    return TypeIndex(SimpleTypeKind::HResult);
+  return UnderlyingTypeIndex;
+}
+
 TypeIndex CodeViewDebug::lowerTypeBasic(const DIBasicType *Ty) {
   TypeIndex Index;
   dwarf::TypeKind Kind;
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
index 41350d42f7e..24d785b8d4b 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
@@ -190,6 +190,7 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
   codeview::TypeIndex getTypeIndex(DITypeRef Ty);
 
   codeview::TypeIndex lowerType(const DIType *Ty);
+  codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty);
   codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty);
   codeview::TypeIndex lowerTypePointer(const DIDerivedType *Ty);
   codeview::TypeIndex lowerTypeMemberPointer(const DIDerivedType *Ty);