Fix PR1146: parameter attributes are longer part of

the function type, instead they belong to functions
and function calls.  This is an updated and slightly
corrected version of Reid Spencer's original patch.
The only known problem is that auto-upgrading of
bitcode files doesn't seem to work properly (see
test/Bitcode/AutoUpgradeIntrinsics.ll).  Hopefully
a bitcode guru (who might that be? :) ) will fix it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44359 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 29 insertions, 5 deletions

diff --git a/lib/VMCore/Function.cpp b/lib/VMCore/Function.cpp
index 2b83e6b..023cb55 100644
--- a/lib/VMCore/Function.cpp
+++ b/lib/VMCore/Function.cpp
@@ -161,7 +161,7 @@ ParamAttrsList::areCompatible(const ParamAttrsList *A, const ParamAttrsList *B){
 void 
 ParamAttrsList::Profile(FoldingSetNodeID &ID) const {
   for (unsigned i = 0; i < attrs.size(); ++i) {
-    unsigned val = attrs[i].attrs << 16 | attrs[i].index;
+    uint32_t val = uint32_t(attrs[i].attrs) << 16 | attrs[i].index;
     ID.AddInteger(val);
   }
 }
@@ -170,7 +170,10 @@ static ManagedStatic<FoldingSet<ParamAttrsList> > ParamAttrsLists;
 
 ParamAttrsList *
 ParamAttrsList::get(const ParamAttrsVector &attrVec) {
-  assert(!attrVec.empty() && "Illegal to create empty ParamAttrsList");
+  // If there are no attributes then return a null ParamAttrsList pointer.
+  if (attrVec.empty())
+    return 0;
+
 #ifndef NDEBUG
   for (unsigned i = 0, e = attrVec.size(); i < e; ++i) {
     assert(attrVec[i].attrs != ParamAttr::None
@@ -179,15 +182,22 @@ ParamAttrsList::get(const ParamAttrsVector &attrVec) {
            && "Misordered ParamAttrsList!");
   }
 #endif
+
+  // Otherwise, build a key to look up the existing attributes.
   ParamAttrsList key(attrVec);
   FoldingSetNodeID ID;
   key.Profile(ID);
   void *InsertPos;
   ParamAttrsList* PAL = ParamAttrsLists->FindNodeOrInsertPos(ID, InsertPos);
+
+  // If we didn't find any existing attributes of the same shape then
+  // create a new one and insert it.
   if (!PAL) {
     PAL = new ParamAttrsList(attrVec);
     ParamAttrsLists->InsertNode(PAL, InsertPos);
   }
+
+  // Return the ParamAttrsList that we found or created.
   return PAL;
 }
 
@@ -201,8 +211,8 @@ ParamAttrsList::~ParamAttrsList() {
 
 Function::Function(const FunctionType *Ty, LinkageTypes Linkage,
                    const std::string &name, Module *ParentModule)
-  : GlobalValue(PointerType::get(Ty), Value::FunctionVal, 0, 0, Linkage, name) {
-  ParamAttrs = 0;
+  : GlobalValue(PointerType::get(Ty), Value::FunctionVal, 0, 0, Linkage, name),
+    ParamAttrs(0) {
   SymTab = new ValueSymbolTable();
 
   assert((getReturnType()->isFirstClassType() ||getReturnType() == Type::VoidTy)
@@ -259,16 +269,30 @@ void Function::setParent(Module *parent) {
     LeakDetector::removeGarbageObject(this);
 }
 
-void Function::setParamAttrs(ParamAttrsList *attrs) { 
+void Function::setParamAttrs(const ParamAttrsList *attrs) {
+  // Avoid deleting the ParamAttrsList if they are setting the
+  // attributes to the same list.
+  if (ParamAttrs == attrs)
+    return;
+
+  // Drop reference on the old ParamAttrsList
   if (ParamAttrs)
     ParamAttrs->dropRef();
 
+  // Add reference to the new ParamAttrsList
   if (attrs)
     attrs->addRef();
 
+  // Set the new ParamAttrsList.
   ParamAttrs = attrs; 
 }
 
+bool Function::isStructReturn() const {
+  if (ParamAttrs)
+    return ParamAttrs->paramHasAttr(1, ParamAttr::StructRet);
+  return false;
+}
+
 const FunctionType *Function::getFunctionType() const {
   return cast<FunctionType>(getType()->getElementType());
 }