1 files changed, 45 insertions, 21 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index 59056b0ff5d..6d43143253e 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -1882,27 +1882,22 @@ TypeIndex CodeViewDebug::lowerTypeMemberFunction(const DISubroutineType *Ty,
   // Lower the containing class type.
   TypeIndex ClassType = getTypeIndex(ClassTy);
 
-  SmallVector<TypeIndex, 8> ReturnAndArgTypeIndices;
-  for (DITypeRef ArgTypeRef : Ty->getTypeArray())
-    ReturnAndArgTypeIndices.push_back(getTypeIndex(ArgTypeRef));
+  DITypeRefArray ReturnAndArgs = Ty->getTypeArray();
+
+  unsigned Index = 0;
+  SmallVector<TypeIndex, 8> ArgTypeIndices;
+  TypeIndex ReturnTypeIndex = getTypeIndex(ReturnAndArgs[Index++]);
 
-  // MSVC uses type none for variadic argument.
-  if (ReturnAndArgTypeIndices.size() > 1 &&
-      ReturnAndArgTypeIndices.back() == TypeIndex::Void()) {
-    ReturnAndArgTypeIndices.back() = TypeIndex::None();
-  }
-  TypeIndex ReturnTypeIndex = TypeIndex::Void();
-  ArrayRef<TypeIndex> ArgTypeIndices = None;
-  if (!ReturnAndArgTypeIndices.empty()) {
-    auto ReturnAndArgTypesRef = makeArrayRef(ReturnAndArgTypeIndices);
-    ReturnTypeIndex = ReturnAndArgTypesRef.front();
-    ArgTypeIndices = ReturnAndArgTypesRef.drop_front();
-  }
   TypeIndex ThisTypeIndex;
-  if (!IsStaticMethod && !ArgTypeIndices.empty()) {
-    ThisTypeIndex = ArgTypeIndices.front();
-    ArgTypeIndices = ArgTypeIndices.drop_front();
-  }
+  if (!IsStaticMethod && ReturnAndArgs.size() > 1)
+    ThisTypeIndex = getTypeIndexForThisPtr(ReturnAndArgs[Index++], Ty);
+
+  while (Index < ReturnAndArgs.size())
+    ArgTypeIndices.push_back(getTypeIndex(ReturnAndArgs[Index++]));
+
+  // MSVC uses type none for variadic argument.
+  if (!ArgTypeIndices.empty() && ArgTypeIndices.back() == TypeIndex::Void())
+    ArgTypeIndices.back() = TypeIndex::None();
 
   ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices);
   TypeIndex ArgListIndex = TypeTable.writeLeafType(ArgListRec);
@@ -1992,8 +1987,8 @@ static ClassOptions getCommonClassOptions(const DICompositeType *Ty) {
     CO |= ClassOptions::Nested;
 
   // Put the Scoped flag on function-local types. MSVC puts this flag for enum
-  // type only when it has an immediate function scope. Clang never puts enums 
-  // inside DILexicalBlock scopes. Enum types, as generated by clang, are 
+  // type only when it has an immediate function scope. Clang never puts enums
+  // inside DILexicalBlock scopes. Enum types, as generated by clang, are
   // always in function, class, or file scopes.
   if (Ty->getTag() == dwarf::DW_TAG_enumeration_type) {
     if (ImmediateScope && isa<DISubprogram>(ImmediateScope))
@@ -2449,6 +2444,35 @@ TypeIndex CodeViewDebug::getTypeIndex(DITypeRef TypeRef, DITypeRef ClassTyRef) {
   return recordTypeIndexForDINode(Ty, TI, ClassTy);
 }
 
+codeview::TypeIndex
+CodeViewDebug::getTypeIndexForThisPtr(DITypeRef TypeRef,
+                                      const DISubroutineType *SubroutineTy) {
+  const DIType *Ty = TypeRef.resolve();
+
+  PointerOptions Options = PointerOptions::None;
+  if (SubroutineTy->getFlags() & DINode::DIFlags::FlagLValueReference)
+    Options = PointerOptions::LValueRefThisPointer;
+  else if (SubroutineTy->getFlags() & DINode::DIFlags::FlagRValueReference)
+    Options = PointerOptions::RValueRefThisPointer;
+
+  // Check if we've already translated this type.  If there is no ref qualifier
+  // on the function then we look up this pointer type with no associated class
+  // so that the TypeIndex for the this pointer can be shared with the type
+  // index for other pointers to this class type.  If there is a ref qualifier
+  // then we lookup the pointer using the subroutine as the parent type.
+  const DIType *ParentTy = nullptr;
+  if (Options != PointerOptions::None)
+    ParentTy = SubroutineTy;
+
+  auto I = TypeIndices.find({Ty, SubroutineTy});
+  if (I != TypeIndices.end())
+    return I->second;
+
+  TypeLoweringScope S(*this);
+  TypeIndex TI = lowerTypePointer(cast<DIDerivedType>(Ty), Options);
+  return recordTypeIndexForDINode(Ty, TI, SubroutineTy);
+}
+
 TypeIndex CodeViewDebug::getTypeIndexForReferenceTo(DITypeRef TypeRef) {
   DIType *Ty = TypeRef.resolve();
   PointerRecord PR(getTypeIndex(Ty),