Make the AttrListPtr object a part of the LLVMContext.

When code deletes the context, the AttributeImpls that the AttrListPtr points to
are now invalid. Therefore, instead of keeping a separate managed static for the
AttrListPtrs that's reference counted, move it into the LLVMContext and delete
it when deleting the AttributeImpls.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168354 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 46 insertions, 86 deletions

diff --git a/lib/VMCore/Attributes.cpp b/lib/VMCore/Attributes.cpp
index 68aa954..55722bc 100644
--- a/lib/VMCore/Attributes.cpp
+++ b/lib/VMCore/Attributes.cpp
@@ -355,62 +355,8 @@ uint64_t AttributesImpl::getStackAlignment() const {
 // AttributeListImpl Definition
 //===----------------------------------------------------------------------===//
 
-namespace llvm {
-  class AttributeListImpl;
-}
-
-static ManagedStatic<FoldingSet<AttributeListImpl> > AttributesLists;
-
-namespace llvm {
-static ManagedStatic<sys::SmartMutex<true> > ALMutex;
-
-class AttributeListImpl : public FoldingSetNode {
-  sys::cas_flag RefCount;
-
-  // AttributesList is uniqued, these should not be publicly available.
-  void operator=(const AttributeListImpl &) LLVM_DELETED_FUNCTION;
-  AttributeListImpl(const AttributeListImpl &) LLVM_DELETED_FUNCTION;
-  ~AttributeListImpl();                        // Private implementation
-public:
-  SmallVector<AttributeWithIndex, 4> Attrs;
-
-  AttributeListImpl(ArrayRef<AttributeWithIndex> attrs)
-    : Attrs(attrs.begin(), attrs.end()) {
-    RefCount = 0;
-  }
-
-  void AddRef() {
-    sys::SmartScopedLock<true> Lock(*ALMutex);
-    ++RefCount;
-  }
-  void DropRef() {
-    sys::SmartScopedLock<true> Lock(*ALMutex);
-    if (!AttributesLists.isConstructed())
-      return;
-    sys::cas_flag new_val = --RefCount;
-    if (new_val == 0)
-      delete this;
-  }
-
-  void Profile(FoldingSetNodeID &ID) const {
-    Profile(ID, Attrs);
-  }
-  static void Profile(FoldingSetNodeID &ID, ArrayRef<AttributeWithIndex> Attrs){
-    for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
-      ID.AddInteger(Attrs[i].Attrs.Raw());
-      ID.AddInteger(Attrs[i].Index);
-    }
-  }
-};
-
-} // end llvm namespace
-
-AttributeListImpl::~AttributeListImpl() {
-  // NOTE: Lock must be acquired by caller.
-  AttributesLists->RemoveNode(this);
-}
-
-AttrListPtr AttrListPtr::get(ArrayRef<AttributeWithIndex> Attrs) {
+AttrListPtr AttrListPtr::get(LLVMContext &C,
+                             ArrayRef<AttributeWithIndex> Attrs) {
   // If there are no attributes then return a null AttributesList pointer.
   if (Attrs.empty())
     return AttrListPtr();
@@ -425,51 +371,36 @@ AttrListPtr AttrListPtr::get(ArrayRef<AttributeWithIndex> Attrs) {
 #endif
 
   // Otherwise, build a key to look up the existing attributes.
+  LLVMContextImpl *pImpl = C.pImpl;
   FoldingSetNodeID ID;
   AttributeListImpl::Profile(ID, Attrs);
-  void *InsertPos;
-
-  sys::SmartScopedLock<true> Lock(*ALMutex);
 
-  AttributeListImpl *PAL =
-    AttributesLists->FindNodeOrInsertPos(ID, InsertPos);
+  void *InsertPoint;
+  AttributeListImpl *PA = pImpl->AttrsLists.FindNodeOrInsertPos(ID,
+                                                                InsertPoint);
 
   // If we didn't find any existing attributes of the same shape then
   // create a new one and insert it.
-  if (!PAL) {
-    PAL = new AttributeListImpl(Attrs);
-    AttributesLists->InsertNode(PAL, InsertPos);
+  if (!PA) {
+    PA = new AttributeListImpl(Attrs);
+    pImpl->AttrsLists.InsertNode(PA, InsertPoint);
   }
 
   // Return the AttributesList that we found or created.
-  return AttrListPtr(PAL);
+  return AttrListPtr(PA);
 }
 
 //===----------------------------------------------------------------------===//
 // AttrListPtr Method Implementations
 //===----------------------------------------------------------------------===//
 
-AttrListPtr::AttrListPtr(AttributeListImpl *LI) : AttrList(LI) {
-  if (LI) LI->AddRef();
-}
-
-AttrListPtr::AttrListPtr(const AttrListPtr &P) : AttrList(P.AttrList) {
-  if (AttrList) AttrList->AddRef();
-}
-
 const AttrListPtr &AttrListPtr::operator=(const AttrListPtr &RHS) {
-  sys::SmartScopedLock<true> Lock(*ALMutex);
   if (AttrList == RHS.AttrList) return *this;
-  if (AttrList) AttrList->DropRef();
+
   AttrList = RHS.AttrList;
-  if (AttrList) AttrList->AddRef();
   return *this;
 }
 
-AttrListPtr::~AttrListPtr() {
-  if (AttrList) AttrList->DropRef();
-}
-
 /// getNumSlots - Return the number of slots used in this attribute list.
 /// This is the number of arguments that have an attribute set on them
 /// (including the function itself).
@@ -507,6 +438,7 @@ bool AttrListPtr::hasAttrSomewhere(Attributes::AttrVal Attr) const {
   for (unsigned i = 0, e = Attrs.size(); i != e; ++i)
     if (Attrs[i].Attrs.hasAttribute(Attr))
       return true;
+
   return false;
 }
 
@@ -562,7 +494,7 @@ AttrListPtr AttrListPtr::addAttr(LLVMContext &C, unsigned Idx,
                        OldAttrList.begin()+i, OldAttrList.end());
   }
 
-  return get(NewAttrList);
+  return get(C, NewAttrList);
 }
 
 AttrListPtr AttrListPtr::removeAttr(LLVMContext &C, unsigned Idx,
@@ -601,7 +533,7 @@ AttrListPtr AttrListPtr::removeAttr(LLVMContext &C, unsigned Idx,
   NewAttrList.insert(NewAttrList.end(),
                      OldAttrList.begin()+i, OldAttrList.end());
 
-  return get(NewAttrList);
+  return get(C, NewAttrList);
 }
 
 void AttrListPtr::dump() const {
diff --git a/lib/VMCore/AttributesImpl.h b/lib/VMCore/AttributesImpl.h
index b4a0f61..5c107e1 100644
--- a/lib/VMCore/AttributesImpl.h
+++ b/lib/VMCore/AttributesImpl.h
@@ -15,12 +15,11 @@
 #ifndef LLVM_ATTRIBUTESIMPL_H
 #define LLVM_ATTRIBUTESIMPL_H
 
+#include "llvm/Attributes.h"
 #include "llvm/ADT/FoldingSet.h"
 
 namespace llvm {
 
-class Attributes;
-
 class AttributesImpl : public FoldingSetNode {
   uint64_t Bits;                // FIXME: We will be expanding this.
 public:
@@ -46,6 +45,27 @@ public:
   }
 };
 
+class AttributeListImpl : public FoldingSetNode {
+  // AttributesList is uniqued, these should not be publicly available.
+  void operator=(const AttributeListImpl &) LLVM_DELETED_FUNCTION;
+  AttributeListImpl(const AttributeListImpl &) LLVM_DELETED_FUNCTION;
+public:
+  SmallVector<AttributeWithIndex, 4> Attrs;
+
+  AttributeListImpl(ArrayRef<AttributeWithIndex> attrs)
+    : Attrs(attrs.begin(), attrs.end()) {}
+
+  void Profile(FoldingSetNodeID &ID) const {
+    Profile(ID, Attrs);
+  }
+  static void Profile(FoldingSetNodeID &ID, ArrayRef<AttributeWithIndex> Attrs){
+    for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
+      ID.AddInteger(Attrs[i].Attrs.Raw());
+      ID.AddInteger(Attrs[i].Index);
+    }
+  }
+};
+
 } // end llvm namespace
 
 #endif
diff --git a/lib/VMCore/LLVMContextImpl.cpp b/lib/VMCore/LLVMContextImpl.cpp
index 74247bd..d35d284 100644
--- a/lib/VMCore/LLVMContextImpl.cpp
+++ b/lib/VMCore/LLVMContextImpl.cpp
@@ -97,11 +97,18 @@ LLVMContextImpl::~LLVMContextImpl() {
 
   // Destroy attributes.
   for (FoldingSetIterator<AttributesImpl> I = AttrsSet.begin(),
-         E = AttrsSet.end(); I != E;) {
+         E = AttrsSet.end(); I != E; ) {
     FoldingSetIterator<AttributesImpl> Elem = I++;
     delete &*Elem;
   }
 
+  // Destroy attribute lists.
+  for (FoldingSetIterator<AttributeListImpl> I = AttrsLists.begin(),
+         E = AttrsLists.end(); I != E; ) {
+    FoldingSetIterator<AttributeListImpl> Elem = I++;
+    delete &*Elem;
+  }
+
   // Destroy MDNodes.  ~MDNode can move and remove nodes between the MDNodeSet
   // and the NonUniquedMDNodes sets, so copy the values out first.
   SmallVector<MDNode*, 8> MDNodes;
diff --git a/lib/VMCore/LLVMContextImpl.h b/lib/VMCore/LLVMContextImpl.h
index ee31814..90cf424 100644
--- a/lib/VMCore/LLVMContextImpl.h
+++ b/lib/VMCore/LLVMContextImpl.h
@@ -256,7 +256,8 @@ public:
   FPMapTy FPConstants;
 
   FoldingSet<AttributesImpl> AttrsSet;
-  
+  FoldingSet<AttributeListImpl> AttrsLists;
+
   StringMap<Value*> MDStringCache;
 
   FoldingSet<MDNode> MDNodeSet;