3 files changed, 16 insertions, 9 deletions
diff --git a/lib/IR/AsmWriter.cpp b/lib/IR/AsmWriter.cpp
index 7afefdc7ac..398e3d5f2a 100644
--- a/lib/IR/AsmWriter.cpp
+++ b/lib/IR/AsmWriter.cpp
@@ -1786,6 +1786,9 @@ void AssemblyWriter::printInstruction(const Instruction &I) {
       (isa<StoreInst>(I) && cast<StoreInst>(I).isAtomic()))
     Out << " atomic";
 
+  if (isa<AtomicCmpXchgInst>(I) && cast<AtomicCmpXchgInst>(I).isWeak())
+    Out << " weak";
+
   // If this is a volatile operation, print out the volatile marker.
   if ((isa<LoadInst>(I)  && cast<LoadInst>(I).isVolatile()) ||
       (isa<StoreInst>(I) && cast<StoreInst>(I).isVolatile()) ||
diff --git a/lib/IR/Instruction.cpp b/lib/IR/Instruction.cpp
index abb4e45576..86421c4ae9 100644
--- a/lib/IR/Instruction.cpp
+++ b/lib/IR/Instruction.cpp
@@ -300,6 +300,7 @@ static bool haveSameSpecialState(const Instruction *I1, const Instruction *I2,
            FI->getSynchScope() == cast<FenceInst>(I2)->getSynchScope();
   if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(I1))
     return CXI->isVolatile() == cast<AtomicCmpXchgInst>(I2)->isVolatile() &&
+           CXI->isWeak() == cast<AtomicCmpXchgInst>(I2)->isWeak() &&
            CXI->getSuccessOrdering() ==
                cast<AtomicCmpXchgInst>(I2)->getSuccessOrdering() &&
            CXI->getFailureOrdering() ==
diff --git a/lib/IR/Instructions.cpp b/lib/IR/Instructions.cpp
index 051d63f7fc..a5ceacb563 100644
--- a/lib/IR/Instructions.cpp
+++ b/lib/IR/Instructions.cpp
@@ -1251,10 +1251,11 @@ AtomicCmpXchgInst::AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal,
                                      AtomicOrdering FailureOrdering,
                                      SynchronizationScope SynchScope,
                                      Instruction *InsertBefore)
-  : Instruction(Cmp->getType(), AtomicCmpXchg,
-                OperandTraits<AtomicCmpXchgInst>::op_begin(this),
-                OperandTraits<AtomicCmpXchgInst>::operands(this),
-                InsertBefore) {
+    : Instruction(
+          StructType::get(Cmp->getType(), Type::getInt1Ty(Cmp->getContext()),
+                          nullptr),
+          AtomicCmpXchg, OperandTraits<AtomicCmpXchgInst>::op_begin(this),
+          OperandTraits<AtomicCmpXchgInst>::operands(this), InsertBefore) {
   Init(Ptr, Cmp, NewVal, SuccessOrdering, FailureOrdering, SynchScope);
 }
 
@@ -1263,13 +1264,14 @@ AtomicCmpXchgInst::AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal,
                                      AtomicOrdering FailureOrdering,
                                      SynchronizationScope SynchScope,
                                      BasicBlock *InsertAtEnd)
-  : Instruction(Cmp->getType(), AtomicCmpXchg,
-                OperandTraits<AtomicCmpXchgInst>::op_begin(this),
-                OperandTraits<AtomicCmpXchgInst>::operands(this),
-                InsertAtEnd) {
+    : Instruction(
+          StructType::get(Cmp->getType(), Type::getInt1Ty(Cmp->getContext()),
+                          nullptr),
+          AtomicCmpXchg, OperandTraits<AtomicCmpXchgInst>::op_begin(this),
+          OperandTraits<AtomicCmpXchgInst>::operands(this), InsertAtEnd) {
   Init(Ptr, Cmp, NewVal, SuccessOrdering, FailureOrdering, SynchScope);
 }
- 
+
 //===----------------------------------------------------------------------===//
 //                       AtomicRMWInst Implementation
 //===----------------------------------------------------------------------===//
@@ -3604,6 +3606,7 @@ AtomicCmpXchgInst *AtomicCmpXchgInst::clone_impl() const {
                           getSuccessOrdering(), getFailureOrdering(),
                           getSynchScope());
   Result->setVolatile(isVolatile());
+  Result->setWeak(isWeak());
   return Result;
 }