Revert constant-folding change that will miscompile in some cases.

[oota-llvm.git] / lib / VMCore / Type.cpp

diff --git a/lib/VMCore/Type.cpp b/lib/VMCore/Type.cpp
index 4554826c34bbcdd6bc5f96cec11038623bc8c9df..d7fe2d1cfbeea94daec09b222e85331f8d515ea6 100644 (file)
--- a/lib/VMCore/Type.cpp
+++ b/lib/VMCore/Type.cpp
@@ -437,16 +437,35 @@ const IntegerType *Type::Int64Ty = new BuiltinIntegerType(64);
 //                          Derived Type Constructors
 //===----------------------------------------------------------------------===//
 
+/// isValidReturnType - Return true if the specified type is valid as a return
+/// type.
+bool FunctionType::isValidReturnType(const Type *RetTy) {
+  if (RetTy->isFirstClassType())
+    return true;
+  if (RetTy == Type::VoidTy || isa<OpaqueType>(RetTy))
+    return true;
+  
+  // If this is a multiple return case, verify that each return is a first class
+  // value and that there is at least one value.
+  const StructType *SRetTy = dyn_cast<StructType>(RetTy);
+  if (SRetTy == 0 || SRetTy->getNumElements() == 0)
+    return false;
+  
+  for (unsigned i = 0, e = SRetTy->getNumElements(); i != e; ++i)
+    if (!SRetTy->getElementType(i)->isFirstClassType())
+      return false;
+  return true;
+}
+
 FunctionType::FunctionType(const Type *Result,
                            const std::vector<const Type*> &Params,
                            bool IsVarArgs)
   : DerivedType(FunctionTyID), isVarArgs(IsVarArgs) {
   ContainedTys = reinterpret_cast<PATypeHandle*>(this+1);
   NumContainedTys = Params.size() + 1; // + 1 for result type
-  assert((Result->isFirstClassType() || Result == Type::VoidTy ||
-          Result->getTypeID() == Type::StructTyID ||
-          isa<OpaqueType>(Result)) &&
-         "LLVM functions cannot return aggregates");
+  assert(isValidReturnType(Result) && "invalid return type for function");
+    
+    
   bool isAbstract = Result->isAbstract();
   new (&ContainedTys[0]) PATypeHandle(Result, this);
 
@@ -531,6 +550,7 @@ void DerivedType::dropAllTypeUses() {
 }
 
 
+namespace {
 
 /// TypePromotionGraph and graph traits - this is designed to allow us to do
 /// efficient SCC processing of type graphs.  This is the exact same as
@@ -541,6 +561,8 @@ struct TypePromotionGraph {
   TypePromotionGraph(Type *T) : Ty(T) {}
 };
 
+}
+
 namespace llvm {
   template <> struct GraphTraits<TypePromotionGraph> {
     typedef Type NodeType;
@@ -1091,9 +1113,8 @@ FunctionType *FunctionType::get(const Type *ReturnType,
                                 bool isVarArg) {
   FunctionValType VT(ReturnType, Params, isVarArg);
   FunctionType *FT = FunctionTypes->get(VT);
-  if (FT) { 
+  if (FT)
     return FT;
-  }
 
   FT = (FunctionType*) new char[sizeof(FunctionType) + 
                                 sizeof(PATypeHandle)*(Params.size()+1)];
@@ -1252,9 +1273,10 @@ StructType *StructType::get(const Type *type, ...) {
   va_list ap;
   std::vector<const llvm::Type*> StructFields;
   va_start(ap, type);
-  do {
+  while (type) {
     StructFields.push_back(type);
-  } while ((type = va_arg(ap, llvm::Type*)));
+    type = va_arg(ap, llvm::Type*);
+  }
   return llvm::StructType::get(StructFields);
 }