#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/DepthFirstIterator.h"
+#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/IRBuilder.h"
bool isInstrumented(const Function *F);
bool isInstrumented(const GlobalAlias *GA);
FunctionType *getArgsFunctionType(FunctionType *T);
+ FunctionType *getTrampolineFunctionType(FunctionType *T);
FunctionType *getCustomFunctionType(FunctionType *T);
InstrumentedABI getInstrumentedABI();
WrapperKind getWrapperKind(Function *F);
Function *buildWrapperFunction(Function *F, StringRef NewFName,
GlobalValue::LinkageTypes NewFLink,
FunctionType *NewFT);
+ Constant *getOrBuildTrampolineFunction(FunctionType *FT, StringRef FName);
public:
DataFlowSanitizer(StringRef ABIListFile = StringRef(),
return FunctionType::get(RetType, ArgTypes, T->isVarArg());
}
-FunctionType *DataFlowSanitizer::getCustomFunctionType(FunctionType *T) {
+FunctionType *DataFlowSanitizer::getTrampolineFunctionType(FunctionType *T) {
assert(!T->isVarArg());
llvm::SmallVector<Type *, 4> ArgTypes;
+ ArgTypes.push_back(T->getPointerTo());
std::copy(T->param_begin(), T->param_end(), std::back_inserter(ArgTypes));
for (unsigned i = 0, e = T->getNumParams(); i != e; ++i)
ArgTypes.push_back(ShadowTy);
return FunctionType::get(T->getReturnType(), ArgTypes, false);
}
+FunctionType *DataFlowSanitizer::getCustomFunctionType(FunctionType *T) {
+ assert(!T->isVarArg());
+ llvm::SmallVector<Type *, 4> ArgTypes;
+ for (FunctionType::param_iterator i = T->param_begin(), e = T->param_end();
+ i != e; ++i) {
+ FunctionType *FT;
+ if (isa<PointerType>(*i) && (FT = dyn_cast<FunctionType>(cast<PointerType>(
+ *i)->getElementType()))) {
+ ArgTypes.push_back(getTrampolineFunctionType(FT)->getPointerTo());
+ ArgTypes.push_back(Type::getInt8PtrTy(*Ctx));
+ } else {
+ ArgTypes.push_back(*i);
+ }
+ }
+ for (unsigned i = 0, e = T->getNumParams(); i != e; ++i)
+ ArgTypes.push_back(ShadowTy);
+ Type *RetType = T->getReturnType();
+ if (!RetType->isVoidTy())
+ ArgTypes.push_back(ShadowPtrTy);
+ return FunctionType::get(T->getReturnType(), ArgTypes, false);
+}
+
bool DataFlowSanitizer::doInitialization(Module &M) {
DL = getAnalysisIfAvailable<DataLayout>();
if (!DL)
return NewF;
}
+Constant *DataFlowSanitizer::getOrBuildTrampolineFunction(FunctionType *FT,
+ StringRef FName) {
+ FunctionType *FTT = getTrampolineFunctionType(FT);
+ Constant *C = Mod->getOrInsertFunction(FName, FTT);
+ Function *F = dyn_cast<Function>(C);
+ if (F && F->isDeclaration()) {
+ F->setLinkage(GlobalValue::LinkOnceODRLinkage);
+ BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", F);
+ std::vector<Value *> Args;
+ Function::arg_iterator AI = F->arg_begin(); ++AI;
+ for (unsigned N = FT->getNumParams(); N != 0; ++AI, --N)
+ Args.push_back(&*AI);
+ CallInst *CI =
+ CallInst::Create(&F->getArgumentList().front(), Args, "", BB);
+ ReturnInst *RI;
+ if (FT->getReturnType()->isVoidTy())
+ RI = ReturnInst::Create(*Ctx, BB);
+ else
+ RI = ReturnInst::Create(*Ctx, CI, BB);
+
+ DFSanFunction DFSF(*this, F, /*IsNativeABI=*/true);
+ Function::arg_iterator ValAI = F->arg_begin(), ShadowAI = AI; ++ValAI;
+ for (unsigned N = FT->getNumParams(); N != 0; ++ValAI, ++ShadowAI, --N)
+ DFSF.ValShadowMap[ValAI] = ShadowAI;
+ DFSanVisitor(DFSF).visitCallInst(*CI);
+ if (!FT->getReturnType()->isVoidTy())
+ new StoreInst(DFSF.getShadow(RI->getReturnValue()),
+ &F->getArgumentList().back(), RI);
+ }
+
+ return C;
+}
+
bool DataFlowSanitizer::runOnModule(Module &M) {
if (!DL)
return false;
FnsToInstrument.push_back(&*i);
}
- // Give function aliases prefixes when necessary.
+ // Give function aliases prefixes when necessary, and build wrappers where the
+ // instrumentedness is inconsistent.
for (Module::alias_iterator i = M.alias_begin(), e = M.alias_end(); i != e;) {
GlobalAlias *GA = &*i;
++i;
bool GAInst = isInstrumented(GA), FInst = isInstrumented(F);
if (GAInst && FInst) {
addGlobalNamePrefix(GA);
+ } else if (GAInst != FInst) {
+ // Non-instrumented alias of an instrumented function, or vice versa.
+ // Replace the alias with a native-ABI wrapper of the aliasee. The pass
+ // below will take care of instrumenting it.
+ Function *NewF =
+ buildWrapperFunction(F, "", GA->getLinkage(), F->getFunctionType());
+ GA->replaceAllUsesWith(NewF);
+ NewF->takeName(GA);
+ GA->eraseFromParent();
+ FnsToInstrument.push_back(NewF);
}
}
}
FunctionType *NewFT = getInstrumentedABI() == IA_Args
? getArgsFunctionType(FT)
: FT;
- Function *NewF =
- buildWrapperFunction(&F, std::string("dfsw$") + std::string(F.getName()),
- GlobalValue::LinkOnceODRLinkage, NewFT);
+ Function *NewF = buildWrapperFunction(
+ &F, std::string("dfsw$") + std::string(F.getName()),
+ GlobalValue::LinkOnceODRLinkage, NewFT);
if (getInstrumentedABI() == IA_TLS)
NewF->removeAttributes(AttributeSet::FunctionIndex, ReadOnlyNoneAttrs);
BasicBlock *Tail = BI->getSuccessor(0);
PHINode *Phi = PHINode::Create(ShadowTy, 2, "", Tail->begin());
Phi->addIncoming(Call, Call->getParent());
- Phi->addIncoming(ZeroShadow, Head);
+ Phi->addIncoming(V1, Head);
Pos = Phi;
return Phi;
} else {
std::vector<Value *> Args;
CallSite::arg_iterator i = CS.arg_begin();
- for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)
- Args.push_back(*i);
+ for (unsigned n = FT->getNumParams(); n != 0; ++i, --n) {
+ Type *T = (*i)->getType();
+ FunctionType *ParamFT;
+ if (isa<PointerType>(T) &&
+ (ParamFT = dyn_cast<FunctionType>(
+ cast<PointerType>(T)->getElementType()))) {
+ std::string TName = "dfst";
+ TName += utostr(FT->getNumParams() - n);
+ TName += "$";
+ TName += F->getName();
+ Constant *T = DFSF.DFS.getOrBuildTrampolineFunction(ParamFT, TName);
+ Args.push_back(T);
+ Args.push_back(
+ IRB.CreateBitCast(*i, Type::getInt8PtrTy(*DFSF.DFS.Ctx)));
+ } else {
+ Args.push_back(*i);
+ }
+ }
i = CS.arg_begin();
for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)