bool LowerIntrinsics::InsertRootInitializers(Function &F, AllocaInst **Roots,
unsigned Count) {
// Scroll past alloca instructions.
BasicBlock::iterator IP = F.getEntryBlock().begin();
while (isa<AllocaInst>(IP)) ++IP;
// Search for initializers in the initial BB.
SmallPtrSet<AllocaInst*,16> InitedRoots;
for (; !CouldBecomeSafePoint(IP); ++IP)
if (StoreInst *SI = dyn_cast<StoreInst>(IP))
if (AllocaInst *AI =
dyn_cast<AllocaInst>(SI->getOperand(1)->stripPointerCasts()))
InitedRoots.insert(AI);
// Add root initializers.
bool MadeChange = false;
for (AllocaInst **I = Roots, **E = Roots + Count; I != E; ++I)
if (!InitedRoots.count(*I)) {
StoreInst* SI = new StoreInst(ConstantPointerNull::get(cast<PointerType>(
cast<PointerType>((*I)->getType())->getElementType())),
*I);
SI->insertAfter(*I);
MadeChange = true;
}
return MadeChange;
}
bool LowerIntrinsics::InsertRootInitializers(Function &F, Instruction **Roots,
unsigned Count) {
// Scroll past alloca instructions.
BasicBlock::iterator IP = F.getEntryBlock().begin();
while (isa<AllocaInst>(IP)) ++IP;
// Search for initializers in the initial BB.
SmallPtrSet<AllocaInst*,16> InitedRoots;
for (; !CouldBecomeSafePoint(IP); ++IP)
if (StoreInst *SI = dyn_cast<StoreInst>(IP))
if (AllocaInst *AI =
dyn_cast<AllocaInst>(SI->getOperand(1)->stripPointerCasts()))
InitedRoots.insert(AI);
// Add root initializers.
bool MadeChange = false;
for (Instruction **II = Roots, **IE = Roots + Count; II != IE; ++II) {
// Trace back through GEPs to find the actual alloca.
Instruction *I = *II;
while (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(I))
I = cast<Instruction>(GEP->getPointerOperand());
AllocaInst *AI = cast<AllocaInst>(I);
if (!InitedRoots.count(AI)) {
Type *ElemTy = cast<PointerType>((*II)->getType())->getElementType();
PointerType *PElemTy = cast<PointerType>(ElemTy);
StoreInst* SI = new StoreInst(ConstantPointerNull::get(PElemTy), *II);
SI->insertAfter(*II);
MadeChange = true;
}
}
return MadeChange;
}
bool TartGCStrategy::insertRootInitializers(Function & fn, AllocaInst ** roots, unsigned count) {
// Scroll past alloca instructions.
BasicBlock::iterator ip = fn.getEntryBlock().begin();
while (isa<AllocaInst>(ip)) {
++ip;
}
// Search for initializers in the initial BB.
SmallPtrSet<AllocaInst*,16> initedRoots;
for (; !couldBecomeSafePoint(ip); ++ip) {
if (StoreInst * si = dyn_cast<StoreInst>(ip)) {
if (AllocaInst * ai = dyn_cast<AllocaInst>(si->getOperand(1)->stripPointerCasts())) {
initedRoots.insert(ai);
}
}
}
// Add root initializers.
bool madeChange = false;
// Initialize each root to null.
for (AllocaInst ** ai = roots, ** E = roots + count; ai != E; ++ai) {
if (!initedRoots.count(*ai)) {
Type * type = cast<PointerType>((*ai)->getType())->getElementType();
StoreInst * storeInst;
if (PointerType * ptype = dyn_cast<PointerType>(type)) {
storeInst = new StoreInst(ConstantPointerNull::get(ptype), *ai);
} else {
storeInst = new StoreInst(ConstantAggregateZero::get(type), *ai);
}
storeInst->insertAfter(*ai);
madeChange = true;
}
}
return madeChange;
}
//
// Method: runOnModule()
//
// Description:
// Entry point for this LLVM pass.
// Clone functions that take LoadInsts as arguments
//
// Inputs:
// M - A reference to the LLVM module to transform
//
// Outputs:
// M - The transformed LLVM module.
//
// Return value:
// true - The module was modified.
// false - The module was not modified.
//
bool LoadArgs::runOnModule(Module& M) {
std::map<std::pair<Function*, const Type * > , Function* > fnCache;
bool changed;
do {
changed = false;
for (Module::iterator Func = M.begin(); Func != M.end(); ++Func) {
for (Function::iterator B = Func->begin(), FE = Func->end(); B != FE; ++B) {
for (BasicBlock::iterator I = B->begin(), BE = B->end(); I != BE;) {
CallInst *CI = dyn_cast<CallInst>(I++);
if(!CI)
continue;
if(CI->hasByValArgument())
continue;
// if the CallInst calls a function, that is externally defined,
// or might be changed, ignore this call site.
Function *F = CI->getCalledFunction();
if (!F || (F->isDeclaration() || F->mayBeOverridden()))
continue;
if(F->hasStructRetAttr())
continue;
if(F->isVarArg())
continue;
// find the argument we must replace
Function::arg_iterator ai = F->arg_begin(), ae = F->arg_end();
unsigned argNum = 0;
for(; argNum < CI->getNumArgOperands();argNum++, ++ai) {
// do not care about dead arguments
if(ai->use_empty())
continue;
if(F->getAttributes().getParamAttributes(argNum).hasAttrSomewhere(Attribute::SExt) ||
F->getAttributes().getParamAttributes(argNum).hasAttrSomewhere(Attribute::ZExt))
continue;
if (isa<LoadInst>(CI->getArgOperand(argNum)))
break;
}
// if no argument was a GEP operator to be changed
if(ai == ae)
continue;
LoadInst *LI = dyn_cast<LoadInst>(CI->getArgOperand(argNum));
Instruction * InsertPt = &(Func->getEntryBlock().front());
AllocaInst *NewVal = new AllocaInst(LI->getType(), "",InsertPt);
StoreInst *Copy = new StoreInst(LI, NewVal);
Copy->insertAfter(LI);
/*if(LI->getParent() != CI->getParent())
continue;
// Also check that there is no store after the load.
// TODO: Check if the load/store do not alias.
BasicBlock::iterator bii = LI->getParent()->begin();
Instruction *BII = bii;
while(BII != LI) {
++bii;
BII = bii;
}
while(BII != CI) {
if(isa<StoreInst>(BII))
break;
++bii;
BII = bii;
}
if(isa<StoreInst>(bii)){
continue;
}*/
// Construct the new Type
// Appends the struct Type at the beginning
std::vector<Type*>TP;
for(unsigned c = 0; c < CI->getNumArgOperands();c++) {
if(c == argNum)
TP.push_back(LI->getPointerOperand()->getType());
TP.push_back(CI->getArgOperand(c)->getType());
}
//return type is same as that of original instruction
FunctionType *NewFTy = FunctionType::get(CI->getType(), TP, false);
numSimplified++;
//if(numSimplified > 1000)
//return true;
Function *NewF;
std::map<std::pair<Function*, const Type* > , Function* >::iterator Test;
Test = fnCache.find(std::make_pair(F, NewFTy));
if(Test != fnCache.end()) {
NewF = Test->second;
} else {
NewF = Function::Create(NewFTy,
GlobalValue::InternalLinkage,
F->getName().str() + ".TEST",
&M);
fnCache[std::make_pair(F, NewFTy)] = NewF;
Function::arg_iterator NI = NewF->arg_begin();
ValueToValueMapTy ValueMap;
unsigned count = 0;
for (Function::arg_iterator II = F->arg_begin(); NI != NewF->arg_end(); ++count, ++NI) {
if(count == argNum) {
NI->setName("LDarg");
continue;
}
ValueMap[II] = NI;
NI->setName(II->getName());
NI->addAttr(F->getAttributes().getParamAttributes(II->getArgNo() + 1));
++II;
}
// Perform the cloning.
SmallVector<ReturnInst*,100> Returns;
CloneFunctionInto(NewF, F, ValueMap, false, Returns);
std::vector<Value*> fargs;
for(Function::arg_iterator ai = NewF->arg_begin(),
ae= NewF->arg_end(); ai != ae; ++ai) {
fargs.push_back(ai);
}
NewF->setAttributes(NewF->getAttributes().addAttributes(
F->getContext(), 0, F->getAttributes().getRetAttributes()));
NewF->setAttributes(NewF->getAttributes().addAttributes(
F->getContext(), ~0, F->getAttributes().getFnAttributes()));
//Get the point to insert the GEP instr.
Instruction *InsertPoint;
for (BasicBlock::iterator insrt = NewF->front().begin(); isa<AllocaInst>(InsertPoint = insrt); ++insrt) {;}
LoadInst *LI_new = new LoadInst(fargs.at(argNum), "", InsertPoint);
fargs.at(argNum+1)->replaceAllUsesWith(LI_new);
}
//this does not seem to be a good idea
AttributeSet NewCallPAL=AttributeSet();
// Get the initial attributes of the call
AttributeSet CallPAL = CI->getAttributes();
AttributeSet RAttrs = CallPAL.getRetAttributes();
AttributeSet FnAttrs = CallPAL.getFnAttributes();
if (!RAttrs.isEmpty())
NewCallPAL=NewCallPAL.addAttributes(F->getContext(),0, RAttrs);
SmallVector<Value*, 8> Args;
for(unsigned j =0;j<CI->getNumArgOperands();j++) {
if(j == argNum) {
Args.push_back(NewVal);
}
Args.push_back(CI->getArgOperand(j));
// position in the NewCallPAL
AttributeSet Attrs = CallPAL.getParamAttributes(j+1);
if (!Attrs.isEmpty())
NewCallPAL=NewCallPAL.addAttributes(F->getContext(),Args.size(), Attrs);
}
// Create the new attributes vec.
if (!FnAttrs.isEmpty())
NewCallPAL=NewCallPAL.addAttributes(F->getContext(),~0, FnAttrs);
CallInst *CallI = CallInst::Create(NewF,Args,"", CI);
CallI->setCallingConv(CI->getCallingConv());
CallI->setAttributes(NewCallPAL);
CI->replaceAllUsesWith(CallI);
CI->eraseFromParent();
changed = true;
}
}
}
} while(changed);
return true;
}
