From e9d34dc7afe06c9adaacad7a678a0cbbf749ea75 Mon Sep 17 00:00:00 2001
From: Anders Carlsson <andersca@mac.com>
Date: Tue, 29 Sep 2009 02:09:01 +0000
Subject: [PATCH] Improve support for member function pointers.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@83039 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CGExprAgg.cpp       | 15 +++++++++++++++
 lib/CodeGen/CGExprConstant.cpp  | 11 +++++++++--
 lib/CodeGen/CodeGenFunction.cpp |  3 ++-
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/lib/CodeGen/CGExprAgg.cpp b/lib/CodeGen/CGExprAgg.cpp
index f710b036a6..3bc8c12974 100644
--- a/lib/CodeGen/CGExprAgg.cpp
+++ b/lib/CodeGen/CGExprAgg.cpp
@@ -198,6 +198,21 @@ void AggExprEmitter::VisitCastExpr(CastExpr *E) {
            "Implicit cast types must be compatible");
     Visit(E->getSubExpr());
     break;
+
+  case CastExpr::CK_NullToMemberPointer: {
+    QualType T = E->getType();
+    const llvm::Type *PtrDiffTy = 
+      CGF.ConvertType(CGF.getContext().getPointerDiffType());
+
+    llvm::Value *NullValue = llvm::Constant::getNullValue(PtrDiffTy);
+    llvm::Value *Ptr = Builder.CreateStructGEP(DestPtr, 0, "ptr");
+    Builder.CreateStore(NullValue, Ptr, VolatileDest);
+    
+    llvm::Value *Adj = Builder.CreateStructGEP(DestPtr, 1, "adj");
+    Builder.CreateStore(NullValue, Adj, VolatileDest);
+
+    break;
+  }
   }
 }
 
diff --git a/lib/CodeGen/CGExprConstant.cpp b/lib/CodeGen/CGExprConstant.cpp
index d1713626ef..3f010b17b0 100644
--- a/lib/CodeGen/CGExprConstant.cpp
+++ b/lib/CodeGen/CGExprConstant.cpp
@@ -785,6 +785,13 @@ llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E,
   return C;
 }
 
+static inline bool isDataMemberPointerType(QualType T) {
+  if (const MemberPointerType *MPT = T->getAs<MemberPointerType>())
+    return !MPT->getPointeeType()->isFunctionType();
+  
+  return false;
+}
+
 llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) {
   // No need to check for member pointers when not compiling C++.
   if (!getContext().getLangOptions().CPlusPlus)
@@ -795,7 +802,7 @@ llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) {
     QualType ElementTy = CAT->getElementType();
 
     // FIXME: Handle arrays of structs that contain member pointers.
-    if (Context.getBaseElementType(ElementTy)->isMemberPointerType()) {
+    if (isDataMemberPointerType(Context.getBaseElementType(ElementTy))) {
       llvm::Constant *Element = EmitNullConstant(ElementTy);
       uint64_t NumElements = CAT->getSize().getZExtValue();
       std::vector<llvm::Constant *> Array(NumElements);
@@ -821,7 +828,7 @@ llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) {
   }
 
   // FIXME: Handle structs that contain member pointers.
-  if (T->isMemberPointerType())
+  if (isDataMemberPointerType(T))
     return llvm::Constant::getAllOnesValue(getTypes().ConvertTypeForMem(T));
 
   return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T));
diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
index fff1a84f70..72009daef6 100644
--- a/lib/CodeGen/CodeGenFunction.cpp
+++ b/lib/CodeGen/CodeGenFunction.cpp
@@ -66,7 +66,8 @@ const llvm::Type *CodeGenFunction::ConvertType(QualType T) {
 }
 
 bool CodeGenFunction::hasAggregateLLVMType(QualType T) {
-  return T->isRecordType() || T->isArrayType() || T->isAnyComplexType();
+  return T->isRecordType() || T->isArrayType() || T->isAnyComplexType() ||
+    T->isMemberFunctionPointerType();
 }
 
 void CodeGenFunction::EmitReturnBlock() {
-- 
2.40.0