From 0e650017acdbbeb0c590e77bbea88c200ea1caef Mon Sep 17 00:00:00 2001
From: Anders Carlsson <andersca@mac.com>
Date: Sun, 17 May 2009 17:41:20 +0000
Subject: [PATCH] Add support for converting member pointer types to LLVM
 types. Also mangle pointer to member functions correctly and add tests.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@71981 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CodeGenTypes.cpp | 19 +++++++++++++------
 lib/CodeGen/Mangle.cpp       |  7 ++++++-
 test/CodeGenCXX/mangle.cpp   | 10 +++++++++-
 3 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/lib/CodeGen/CodeGenTypes.cpp b/lib/CodeGen/CodeGenTypes.cpp
index a9d4615d2a..af791f6318 100644
--- a/lib/CodeGen/CodeGenTypes.cpp
+++ b/lib/CodeGen/CodeGenTypes.cpp
@@ -385,12 +385,19 @@ const llvm::Type *CodeGenTypes::ConvertNewType(QualType T) {
     return llvm::PointerType::get(PointeeType, FTy.getAddressSpace());
   }
 
-  case Type::MemberPointer:
-    // FIXME: Implement C++ pointer-to-member. The GCC representation is
-    // documented here:
-    // http://gcc.gnu.org/onlinedocs/gccint/Type-Layout.html#Type-Layout
-    assert(0 && "FIXME: We can't handle member pointers yet.");
-    return llvm::OpaqueType::get();
+  case Type::MemberPointer: {
+    // FIXME: This is ABI dependent. We use the Itanium C++ ABI.
+    // http://www.codesourcery.com/public/cxx-abi/abi.html#member-pointers
+    // If we ever want to support other ABIs this needs to be abstracted.
+
+    QualType ETy = cast<MemberPointerType>(Ty).getPointeeType();
+    if (ETy->isFunctionType()) {
+      return llvm::StructType::get(ConvertType(Context.getPointerDiffType()), 
+                                   ConvertType(Context.getPointerDiffType()),
+                                   NULL);
+    } else
+      return ConvertType(Context.getPointerDiffType());
+  }
 
   case Type::TemplateSpecialization:
     assert(false && "Dependent types can't get here");
diff --git a/lib/CodeGen/Mangle.cpp b/lib/CodeGen/Mangle.cpp
index c27ef4fd97..c09a13a59f 100644
--- a/lib/CodeGen/Mangle.cpp
+++ b/lib/CodeGen/Mangle.cpp
@@ -608,7 +608,12 @@ void CXXNameMangler::mangleType(const MemberPointerType *T) {
   //  <pointer-to-member-type> ::= M <class type> <member type>
   Out << 'M';
   mangleType(QualType(T->getClass(), 0));
-  mangleType(T->getPointeeType());
+  QualType PointeeType = T->getPointeeType();
+  if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(PointeeType)) {
+    mangleCVQualifiers(FPT->getTypeQuals());
+    mangleType(FPT);
+  } else 
+    mangleType(PointeeType);
 }
 
 void CXXNameMangler::mangleType(const TemplateTypeParmType *T) {
diff --git a/test/CodeGenCXX/mangle.cpp b/test/CodeGenCXX/mangle.cpp
index 86a72011da..ef36a8b23c 100644
--- a/test/CodeGenCXX/mangle.cpp
+++ b/test/CodeGenCXX/mangle.cpp
@@ -75,5 +75,13 @@ void f(S3<true>) {}
 // RUN: grep "_Z1f2S3ILb0EE" %t | count 1 &&
 void f(S3<false>) {}
 
-// RUN: grep "_Z2f22S3ILb1EE" %t | count 1 
+// RUN: grep "_Z2f22S3ILb1EE" %t | count 1 &&
 void f2(S3<100>) {}
+
+struct S;
+
+// RUN: grep "_Z1fM1SKFvvE" %t | count 1 &&
+void f(void (S::*)() const) {}
+
+// RUN: grep "_Z1fM1SFvvE" %t | count 1
+void f(void (S::*)()) {}
-- 
2.40.0