Debug Info: generate a unique identifier for C++ struct, class, union, and enum.

We use CXX mangler to generate unique identifier for external C++ struct,
union, class and enum. Types with unique identifier are added to retained
types by DIBuilder.

Testing cases are updated to reflect the unique identifier generated for types.
The order of MDNodes is changed because of retained types and testing cases
are updated accordingly.

Testing case debug-info-uuid.cpp now emits error with Itanium mangler, since
uuid is not yet handled in Itanium mangler. And it will check for the error
message.

llvm-svn: 189622

1 files changed, 37 insertions, 6 deletions

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index fd495fe7733..fe503982be3 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -599,6 +599,30 @@ llvm::DIType CGDebugInfo::CreateType(const PointerType *Ty,
                                Ty->getPointeeType(), Unit);
 }
 
+/// In C++ mode, types have linkage, so we can rely on the ODR and
+/// on their mangled names, if they're external.
+static SmallString<256>
+getUniqueTagTypeName(const TagType *Ty, CodeGenModule &CGM,
+                     llvm::DICompileUnit TheCU) {
+  SmallString<256> FullName;
+  // FIXME: ODR should apply to ObjC++ exactly the same wasy it does to C++.
+  // For now, only apply ODR with C++.
+  const TagDecl *TD = Ty->getDecl();
+  if (TheCU.getLanguage() != llvm::dwarf::DW_LANG_C_plus_plus ||
+      !TD->isExternallyVisible())
+    return FullName;
+  // Microsoft Mangler does not have support for mangleCXXRTTIName yet.
+  if (CGM.getTarget().getCXXABI().isMicrosoft())
+    return FullName;
+
+  // TODO: This is using the RTTI name. Is there a better way to get
+  // a unique string for a type?
+  llvm::raw_svector_ostream Out(FullName);
+  CGM.getCXXABI().getMangleContext().mangleCXXRTTIName(QualType(Ty, 0), Out);
+  Out.flush();
+  return FullName;
+}
+
 // Creates a forward declaration for a RecordDecl in the given context.
 llvm::DICompositeType
 CGDebugInfo::getOrCreateRecordFwdDecl(const RecordType *Ty,
@@ -621,7 +645,9 @@ CGDebugInfo::getOrCreateRecordFwdDecl(const RecordType *Ty,
   }
 
   // Create the type.
-  return DBuilder.createForwardDecl(Tag, RDName, Ctx, DefUnit, Line);
+  SmallString<256> FullName = getUniqueTagTypeName(Ty, CGM, TheCU);
+  return DBuilder.createForwardDecl(Tag, RDName, Ctx, DefUnit, Line, 0, 0, 0,
+                                    FullName);
 }
 
 // Walk up the context chain and create forward decls for record decls,
@@ -1884,6 +1910,8 @@ llvm::DIType CGDebugInfo::CreateEnumType(const EnumType *Ty) {
     Align = CGM.getContext().getTypeAlign(ED->getTypeForDecl());
   }
 
+  SmallString<256> FullName = getUniqueTagTypeName(Ty, CGM, TheCU);
+
   // If this is just a forward declaration, construct an appropriately
   // marked node and just return it.
   if (!ED->getDefinition()) {
@@ -1894,7 +1922,7 @@ llvm::DIType CGDebugInfo::CreateEnumType(const EnumType *Ty) {
     StringRef EDName = ED->getName();
     return DBuilder.createForwardDecl(llvm::dwarf::DW_TAG_enumeration_type,
                                       EDName, EDContext, DefUnit, Line, 0,
-                                      Size, Align);
+                                      Size, Align, FullName);
   }
 
   // Create DIEnumerator elements for each enumerator.
@@ -1920,7 +1948,7 @@ llvm::DIType CGDebugInfo::CreateEnumType(const EnumType *Ty) {
   llvm::DIType DbgTy =
     DBuilder.createEnumerationType(EnumContext, ED->getName(), DefUnit, Line,
                                    Size, Align, EltArray,
-                                   ClassTy);
+                                   ClassTy, FullName);
   return DbgTy;
 }
 
@@ -2270,20 +2298,23 @@ llvm::DICompositeType CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
   uint64_t Align = CGM.getContext().getTypeAlign(Ty);
   llvm::DICompositeType RealDecl;
 
+  SmallString<256> FullName = getUniqueTagTypeName(Ty, CGM, TheCU);
+
   if (RD->isUnion())
     RealDecl = DBuilder.createUnionType(RDContext, RDName, DefUnit, Line,
-                                        Size, Align, 0, llvm::DIArray());
+                                        Size, Align, 0, llvm::DIArray(), 0,
+                                        FullName);
   else if (RD->isClass()) {
     // FIXME: This could be a struct type giving a default visibility different
     // than C++ class type, but needs llvm metadata changes first.
     RealDecl = DBuilder.createClassType(RDContext, RDName, DefUnit, Line,
                                         Size, Align, 0, 0, llvm::DIType(),
                                         llvm::DIArray(), llvm::DIType(),
-                                        llvm::DIArray());
+                                        llvm::DIArray(), FullName);
   } else
     RealDecl = DBuilder.createStructType(RDContext, RDName, DefUnit, Line,
                                          Size, Align, 0, llvm::DIType(),
-                                         llvm::DIArray());
+                                         llvm::DIArray(), 0, 0, FullName);
 
   RegionMap[Ty->getDecl()] = llvm::WeakVH(RealDecl);
   TypeCache[QualType(Ty, 0).getAsOpaquePtr()] = RealDecl;