diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp
index c86ee30..e948329 100644
--- a/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -18,7 +18,6 @@
 #include "llvm/InlineAsm.h"
 #include "llvm/Instructions.h"
 #include "llvm/Module.h"
-#include "llvm/ParamAttrsList.h"
 #include "llvm/AutoUpgrade.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
@@ -32,11 +31,7 @@
   std::vector<PATypeHolder>().swap(TypeList);
   ValueList.clear();
   
-  // Drop references to ParamAttrs.
-  for (unsigned i = 0, e = ParamAttrs.size(); i != e; ++i)
-    ParamAttrs[i]->dropRef();
-  
-  std::vector<const ParamAttrsList*>().swap(ParamAttrs);
+  std::vector<PAListPtr>().swap(ParamAttrs);
   std::vector<BasicBlock*>().swap(FunctionBBs);
   std::vector<Function*>().swap(FunctionsWithBodies);
   DeferredFunctionInfo.clear();
@@ -205,7 +200,7 @@
   
   SmallVector<uint64_t, 64> Record;
   
-  ParamAttrsVector Attrs;
+  SmallVector<ParamAttrsWithIndex, 8> Attrs;
   
   // Read all the records.
   while (1) {
@@ -242,13 +237,8 @@
         if (Record[i+1] != ParamAttr::None)
           Attrs.push_back(ParamAttrsWithIndex::get(Record[i], Record[i+1]));
       }
-      if (Attrs.empty()) {
-        ParamAttrs.push_back(0);
-      } else {
-        ParamAttrs.push_back(ParamAttrsList::get(Attrs));
-        ParamAttrs.back()->addRef();
-      }
 
+      ParamAttrs.push_back(PAListPtr::get(Attrs.begin(), Attrs.end()));
       Attrs.clear();
       break;
     }
@@ -1062,8 +1052,7 @@
       Func->setCallingConv(Record[1]);
       bool isProto = Record[2];
       Func->setLinkage(GetDecodedLinkage(Record[3]));
-      const ParamAttrsList *PAL = getParamAttrs(Record[4]);
-      Func->setParamAttrs(PAL);
+      Func->setParamAttrs(getParamAttrs(Record[4]));
       
       Func->setAlignment((1 << Record[5]) >> 1);
       if (Record[6]) {
@@ -1427,7 +1416,7 @@
     case bitc::FUNC_CODE_INST_INVOKE: {
       // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
       if (Record.size() < 4) return Error("Invalid INVOKE record");
-      const ParamAttrsList *PAL = getParamAttrs(Record[0]);
+      PAListPtr PAL = getParamAttrs(Record[0]);
       unsigned CCInfo = Record[1];
       BasicBlock *NormalBB = getBasicBlock(Record[2]);
       BasicBlock *UnwindBB = getBasicBlock(Record[3]);
@@ -1565,7 +1554,7 @@
       if (Record.size() < 3)
         return Error("Invalid CALL record");
       
-      const ParamAttrsList *PAL = getParamAttrs(Record[0]);
+      PAListPtr PAL = getParamAttrs(Record[0]);
       unsigned CCInfo = Record[1];
       
       unsigned OpNum = 2;
diff --git a/lib/Bitcode/Reader/BitcodeReader.h b/lib/Bitcode/Reader/BitcodeReader.h
index d7df1a1..9a140d9 100644
--- a/lib/Bitcode/Reader/BitcodeReader.h
+++ b/lib/Bitcode/Reader/BitcodeReader.h
@@ -15,6 +15,7 @@
 #define BITCODE_READER_H
 
 #include "llvm/ModuleProvider.h"
+#include "llvm/ParameterAttributes.h"
 #include "llvm/Type.h"
 #include "llvm/User.h"
 #include "llvm/Bitcode/BitstreamReader.h"
@@ -24,7 +25,6 @@
 
 namespace llvm {
   class MemoryBuffer;
-  class ParamAttrsList;
   
 class BitcodeReaderValueList : public User {
   std::vector<Use> Uses;
@@ -93,7 +93,7 @@
   /// ParamAttrs - The set of parameter attributes by index.  Index zero in the
   /// file is for null, and is thus not represented here.  As such all indices
   /// are off by one.
-  std::vector<const ParamAttrsList*> ParamAttrs;
+  std::vector<PAListPtr> ParamAttrs;
   
   /// FunctionBBs - While parsing a function body, this is a list of the basic
   /// blocks for the function.
@@ -156,10 +156,10 @@
     if (ID >= FunctionBBs.size()) return 0; // Invalid ID
     return FunctionBBs[ID];
   }
-  const ParamAttrsList *getParamAttrs(unsigned i) const {
+  PAListPtr getParamAttrs(unsigned i) const {
     if (i-1 < ParamAttrs.size())
       return ParamAttrs[i-1];
-    return 0;
+    return PAListPtr();
   }
   
   /// getValueTypePair - Read a value/type pair out of the specified record from
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index aaad226..96f045c 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -20,7 +20,6 @@
 #include "llvm/InlineAsm.h"
 #include "llvm/Instructions.h"
 #include "llvm/Module.h"
-#include "llvm/ParamAttrsList.h"
 #include "llvm/TypeSymbolTable.h"
 #include "llvm/ValueSymbolTable.h"
 #include "llvm/Support/MathExtras.h"
@@ -109,17 +108,18 @@
 // Emit information about parameter attributes.
 static void WriteParamAttrTable(const ValueEnumerator &VE, 
                                 BitstreamWriter &Stream) {
-  const std::vector<const ParamAttrsList*> &Attrs = VE.getParamAttrs();
+  const std::vector<PAListPtr> &Attrs = VE.getParamAttrs();
   if (Attrs.empty()) return;
   
   Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
 
   SmallVector<uint64_t, 64> Record;
   for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
-    const ParamAttrsList *A = Attrs[i];
-    for (unsigned op = 0, e = A->size(); op != e; ++op) {
-      Record.push_back(A->getParamIndex(op));
-      Record.push_back(A->getParamAttrsAtIndex(op));
+    const PAListPtr &A = Attrs[i];
+    for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
+      const ParamAttrsWithIndex &PAWI = A.getSlot(i);
+      Record.push_back(PAWI.Index);
+      Record.push_back(PAWI.Attrs);
     }
     
     Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
diff --git a/lib/Bitcode/Writer/ValueEnumerator.cpp b/lib/Bitcode/Writer/ValueEnumerator.cpp
index d2efe07..09a1db3 100644
--- a/lib/Bitcode/Writer/ValueEnumerator.cpp
+++ b/lib/Bitcode/Writer/ValueEnumerator.cpp
@@ -245,10 +245,10 @@
   }
 }
 
-void ValueEnumerator::EnumerateParamAttrs(const ParamAttrsList *PAL) {
-  if (PAL == 0) return;  // null is always 0.
+void ValueEnumerator::EnumerateParamAttrs(const PAListPtr &PAL) {
+  if (PAL.isEmpty()) return;  // null is always 0.
   // Do a lookup.
-  unsigned &Entry = ParamAttrMap[PAL];
+  unsigned &Entry = ParamAttrMap[PAL.getRawPointer()];
   if (Entry == 0) {
     // Never saw this before, add it.
     ParamAttrs.push_back(PAL);
diff --git a/lib/Bitcode/Writer/ValueEnumerator.h b/lib/Bitcode/Writer/ValueEnumerator.h
index 9fb916a..dc40d01 100644
--- a/lib/Bitcode/Writer/ValueEnumerator.h
+++ b/lib/Bitcode/Writer/ValueEnumerator.h
@@ -15,6 +15,7 @@
 #define VALUE_ENUMERATOR_H
 
 #include "llvm/ADT/DenseMap.h"
+#include "llvm/ParameterAttributes.h"
 #include <vector>
 
 namespace llvm {
@@ -24,7 +25,7 @@
 class BasicBlock;
 class Function;
 class Module;
-class ParamAttrsList;
+class PAListPtr;
 class TypeSymbolTable;
 class ValueSymbolTable;
 
@@ -44,9 +45,9 @@
   ValueMapType ValueMap;
   ValueList Values;
   
-  typedef DenseMap<const ParamAttrsList*, unsigned> ParamAttrMapType;
+  typedef DenseMap<void*, unsigned> ParamAttrMapType;
   ParamAttrMapType ParamAttrMap;
-  std::vector<const ParamAttrsList*> ParamAttrs;
+  std::vector<PAListPtr> ParamAttrs;
   
   /// BasicBlocks - This contains all the basic blocks for the currently
   /// incorporated function.  Their reverse mapping is stored in ValueMap.
@@ -75,9 +76,9 @@
     return I->second-1;
   }
   
-  unsigned getParamAttrID(const ParamAttrsList *PAL) const {
-    if (PAL == 0) return 0;  // Null maps to zero.
-    ParamAttrMapType::const_iterator I = ParamAttrMap.find(PAL);
+  unsigned getParamAttrID(const PAListPtr &PAL) const {
+    if (PAL.isEmpty()) return 0;  // Null maps to zero.
+    ParamAttrMapType::const_iterator I = ParamAttrMap.find(PAL.getRawPointer());
     assert(I != ParamAttrMap.end() && "ParamAttr not in ValueEnumerator!");
     return I->second;
   }
@@ -94,7 +95,7 @@
   const std::vector<const BasicBlock*> &getBasicBlocks() const {
     return BasicBlocks; 
   }
-  const std::vector<const ParamAttrsList*> &getParamAttrs() const {
+  const std::vector<PAListPtr> &getParamAttrs() const {
     return ParamAttrs;
   }
 
@@ -115,7 +116,7 @@
   void EnumerateValue(const Value *V);
   void EnumerateType(const Type *T);
   void EnumerateOperandType(const Value *V);
-  void EnumerateParamAttrs(const ParamAttrsList *PAL);
+  void EnumerateParamAttrs(const PAListPtr &PAL);
   
   void EnumerateTypeSymbolTable(const TypeSymbolTable &ST);
   void EnumerateValueSymbolTable(const ValueSymbolTable &ST);