Codegen support for nullptr from C++0x.

llvm-svn: 81835

clang/lib/AST/ExprConstant.cpp

@@ -383,7 +383,8 @@ APValue PointerExprEvaluator::VisitCastExpr(const CastExpr* E) {
 
    // Check for pointer->pointer cast
   if (SubExpr->getType()->isPointerType() ||
-      SubExpr->getType()->isObjCObjectPointerType()) {
+      SubExpr->getType()->isObjCObjectPointerType() ||
+      SubExpr->getType()->isNullPtrType()) {
     APValue Result;
     if (EvaluatePointer(SubExpr, Result, Info))
       return Result;

clang/lib/CodeGen/CGExprScalar.cpp

@@ -308,6 +308,10 @@ public:
     return 0;
   }
 
+  Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
+    return llvm::Constant::getNullValue(ConvertType(E->getType()));
+  }
+    
   // Binary Operators.
   Value *EmitMul(const BinOpInfo &Ops) {
     if (CGF.getContext().getLangOptions().OverflowChecking

clang/lib/CodeGen/CodeGenTypes.cpp

@@ -229,6 +229,12 @@ const llvm::Type *CodeGenTypes::ConvertNewType(QualType T) {
       return getTypeForFormat(getLLVMContext(),
                               Context.getFloatTypeSemantics(T));
 
+    case BuiltinType::NullPtr: {
+      // Model std::nullptr_t as i8*
+      const llvm::Type *Ty = llvm::IntegerType::get(getLLVMContext(), 8);
+      return llvm::PointerType::getUnqual(Ty);
+    }
+        
     case BuiltinType::UInt128:
     case BuiltinType::Int128:
       return llvm::IntegerType::get(getLLVMContext(), 128);

clang/test/CodeGenCXX/nullptr.cpp

@@ -0,0 +1,7 @@
+// RUN: clang-cc -std=c++0x  %s -emit-llvm -o %t
+
+int* a = nullptr;
+
+void f() {
+  int* a = nullptr;
+}