From 02c44f0962c8739c447bc35688d47294f72494aa Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Mon, 5 Aug 2013 22:26:46 +0000
Subject: [PATCH] [ms-cxxabi] Handle template-template arguments

Template-template arguments appear to be a rather simple encoding of the
template's templated tag type.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@187751 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/AST/MicrosoftMangle.cpp             | 17 +++++++++------
 test/CodeGenCXX/mangle-ms-templates.cpp | 29 +++++++++++++++++++++++++
 2 files changed, 39 insertions(+), 7 deletions(-)

diff --git a/lib/AST/MicrosoftMangle.cpp b/lib/AST/MicrosoftMangle.cpp
index 68f57a9212..fb3f87ad13 100644
--- a/lib/AST/MicrosoftMangle.cpp
+++ b/lib/AST/MicrosoftMangle.cpp
@@ -123,7 +123,7 @@ private:
 #undef NON_CANONICAL_TYPE
 #undef TYPE
   
-  void mangleType(const TagType*);
+  void mangleType(const TagDecl *TD);
   void mangleDecayedArrayType(const ArrayType *T, bool IsGlobal);
   void mangleArrayType(const ArrayType *T);
   void mangleFunctionClass(const FunctionDecl *FD);
@@ -904,6 +904,9 @@ void MicrosoftCXXNameMangler::mangleTemplateArg(const TemplateDecl *TD,
       mangleTemplateArg(TD, *I, ArgIndex);
     break;
   case TemplateArgument::Template:
+    mangleType(cast<TagDecl>(
+        TA.getAsTemplate().getAsTemplateDecl()->getTemplatedDecl()));
+    break;
   case TemplateArgument::TemplateExpansion: {
     // Issue a diagnostic.
     DiagnosticsEngine &Diags = Context.getDiags();
@@ -1407,13 +1410,13 @@ void MicrosoftCXXNameMangler::mangleType(const UnresolvedUsingType *T,
 // <class-type>  ::= V <name>
 // <enum-type>   ::= W <size> <name>
 void MicrosoftCXXNameMangler::mangleType(const EnumType *T, SourceRange) {
-  mangleType(cast<TagType>(T));
+  mangleType(cast<TagType>(T)->getDecl());
 }
 void MicrosoftCXXNameMangler::mangleType(const RecordType *T, SourceRange) {
-  mangleType(cast<TagType>(T));
+  mangleType(cast<TagType>(T)->getDecl());
 }
-void MicrosoftCXXNameMangler::mangleType(const TagType *T) {
-  switch (T->getDecl()->getTagKind()) {
+void MicrosoftCXXNameMangler::mangleType(const TagDecl *TD) {
+  switch (TD->getTagKind()) {
     case TTK_Union:
       Out << 'T';
       break;
@@ -1427,10 +1430,10 @@ void MicrosoftCXXNameMangler::mangleType(const TagType *T) {
     case TTK_Enum:
       Out << 'W';
       Out << getASTContext().getTypeSizeInChars(
-                cast<EnumDecl>(T->getDecl())->getIntegerType()).getQuantity();
+                cast<EnumDecl>(TD)->getIntegerType()).getQuantity();
       break;
   }
-  mangleName(T->getDecl());
+  mangleName(TD);
 }
 
 // <type>       ::= <array-type>
diff --git a/test/CodeGenCXX/mangle-ms-templates.cpp b/test/CodeGenCXX/mangle-ms-templates.cpp
index 6e5be65824..25c8b43506 100644
--- a/test/CodeGenCXX/mangle-ms-templates.cpp
+++ b/test/CodeGenCXX/mangle-ms-templates.cpp
@@ -157,6 +157,35 @@ void variadic_class_instantiate() {
 // CHECK: call {{.*}} @"\01??0?$VariadicClass@HD_N@@QAE@XZ"
 // CHECK: call {{.*}} @"\01??0?$VariadicClass@_NDH@@QAE@XZ"
 
+template <typename T>
+struct Second {};
+
+template <typename T, template <class> class>
+struct Type {};
+
+template <template <class> class T>
+struct Type2 {};
+
+template <template <class> class T, bool B>
+struct Thing;
+
+template <template <class> class T>
+struct Thing<T, false> { };
+
+template <template <class> class T>
+struct Thing<T, true> { };
+
+void template_template_fun(Type<Thing<Second, true>, Second>) { }
+// CHECK: "\01?template_template_fun@@YAXU?$Type@U?$Thing@USecond@@$00@@USecond@@@@@Z"
+
+template <typename T>
+void template_template_specialization();
+
+template <>
+void template_template_specialization<void (Type<Thing<Second, true>, Second>)>() {
+}
+// CHECK: "\01??$template_template_specialization@$$A6AXU?$Type@U?$Thing@USecond@@$00@@USecond@@@@@Z@@YAXXZ"
+
 // PR16788
 template <decltype(nullptr)> struct S1 {};
 void f(S1<nullptr>) {}
-- 
2.40.0