diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp index 5ae693b65b2..c74f604f682 100644 --- a/lib/Transforms/IPO/GlobalOpt.cpp +++ b/lib/Transforms/IPO/GlobalOpt.cpp @@ -842,11 +842,34 @@ static void ShrinkGlobalToBoolean(GlobalVariable *GV, Constant *OtherVal) { // Change the store into a boolean store. bool StoringOther = SI->getOperand(0) == OtherVal; // Only do this if we weren't storing a loaded value. + Value *StoreVal; if (StoringOther || SI->getOperand(0) == InitVal) - new StoreInst(ConstantBool::get(StoringOther), NewGV, SI); - } else { + StoreVal = ConstantBool::get(StoringOther); + else { + // Otherwise, we are storing a previously loaded copy. To do this, + // change the copy from copying the original value to just copying the + // bool. + Instruction *StoredVal = cast(SI->getOperand(0)); + + // If we're already replaced the input, StoredVal will be a cast or + // select instruction. If not, it will be a load of the original + // global. + if (LoadInst *LI = dyn_cast(StoredVal)) { + assert(LI->getOperand(0) == GV && "Not a copy!"); + // Insert a new load, to preserve the saved value. + StoreVal = new LoadInst(NewGV, LI->getName()+".b", LI); + } else { + assert((isa(StoredVal) || isa(StoredVal)) && + "This is not a form that we understand!"); + StoreVal = StoredVal->getOperand(0); + assert(isa(StoreVal) && "Not a load of NewGV!"); + } + } + new StoreInst(StoreVal, NewGV, SI); + } else if (!UI->use_empty()) { // Change the load into a load of bool then a select. LoadInst *LI = cast(UI); + std::string Name = LI->getName(); LI->setName(""); LoadInst *NLI = new LoadInst(NewGV, Name+".b", LI); Value *NSI;