SizeOffsetType ObjectSizeOffsetVisitor::visitGlobalVariable(GlobalVariable &GV){
if (!GV.hasDefinitiveInitializer())
return unknown();
APInt Size(IntTyBits, TD->getTypeAllocSize(GV.getType()->getElementType()));
return std::make_pair(align(Size, GV.getAlignment()), Zero);
}
Function *GCOVProfiler::insertCounterWriteout(
ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) {
FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
if (!WriteoutF)
WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage,
"__llvm_gcov_writeout", M);
WriteoutF->setUnnamedAddr(true);
WriteoutF->addFnAttr(Attribute::NoInline);
if (Options.NoRedZone)
WriteoutF->addFnAttr(Attribute::NoRedZone);
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
IRBuilder<> Builder(BB);
Constant *StartFile = getStartFileFunc();
Constant *EmitFunction = getEmitFunctionFunc();
Constant *EmitArcs = getEmitArcsFunc();
Constant *SummaryInfo = getSummaryInfoFunc();
Constant *EndFile = getEndFileFunc();
NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
if (CU_Nodes) {
for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
DICompileUnit CU(CU_Nodes->getOperand(i));
std::string FilenameGcda = mangleName(CU, "gcda");
uint32_t CfgChecksum = FileChecksums.empty() ? 0 : FileChecksums[i];
Builder.CreateCall3(StartFile,
Builder.CreateGlobalStringPtr(FilenameGcda),
Builder.CreateGlobalStringPtr(ReversedVersion),
Builder.getInt32(CfgChecksum));
for (unsigned j = 0, e = CountersBySP.size(); j != e; ++j) {
DISubprogram SP(CountersBySP[j].second);
uint32_t FuncChecksum = Funcs.empty() ? 0 : Funcs[j]->getFuncChecksum();
Builder.CreateCall5(
EmitFunction, Builder.getInt32(j),
Options.FunctionNamesInData ?
Builder.CreateGlobalStringPtr(getFunctionName(SP)) :
Constant::getNullValue(Builder.getInt8PtrTy()),
Builder.getInt32(FuncChecksum),
Builder.getInt8(Options.UseCfgChecksum),
Builder.getInt32(CfgChecksum));
GlobalVariable *GV = CountersBySP[j].first;
unsigned Arcs =
cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
Builder.CreateCall2(EmitArcs,
Builder.getInt32(Arcs),
Builder.CreateConstGEP2_64(GV, 0, 0));
}
Builder.CreateCall(SummaryInfo);
Builder.CreateCall(EndFile);
}
}
Builder.CreateRetVoid();
return WriteoutF;
}
static StringRef GetGVTypeString(const GlobalVariable &G) {
// Types of GlobalVariables are always pointer types.
Type *GType = G.getType()->getElementType();
// For now we support blacklisting struct types only.
if (StructType *SGType = dyn_cast<StructType>(GType)) {
if (!SGType->isLiteral())
return SGType->getName();
}
return "<unknown type>";
}
static std::unique_ptr<StructInfo> getCpuArchStructInfo(Module *module)
{
GlobalVariable *env = module->getGlobalVariable("cpuarchstruct_type_anchor", false);
assert(env);
assert(env->getType() && env->getType()->isPointerTy());
assert(env->getType()->getElementType() && env->getType()->getElementType()->isPointerTy());
PointerType *envDeref = dyn_cast<PointerType>(env->getType()->getElementType());
assert(envDeref && envDeref->getElementType() && envDeref->getElementType()->isStructTy());
StructType *structType = dyn_cast<StructType>(envDeref->getElementType());
assert(structType);
NamedMDNode *mdCuNodes = module->getNamedMetadata("llvm.dbg.cu");
if (!mdCuNodes) {
return nullptr;
}
std::shared_ptr<DITypeIdentifierMap> typeIdentifierMap(new DITypeIdentifierMap(generateDITypeIdentifierMap(mdCuNodes)));
DICompositeType *diStructType = nullptr;
for ( unsigned i = 0; i < mdCuNodes->getNumOperands() && !diStructType; ++i )
{
DICompileUnit diCu(mdCuNodes->getOperand(i));
for ( unsigned j = 0; j < diCu.getGlobalVariables().getNumElements(); ++j )
{
DIGlobalVariable diGlobalVar(diCu.getGlobalVariables().getElement(j));
if (diGlobalVar.getName() != "cpuarchstruct_type_anchor") {
continue;
}
assert(diGlobalVar.getType().isDerivedType());
DIDerivedType diEnvPtrType(diGlobalVar.getType());
assert(diEnvPtrType.getTypeDerivedFrom().resolve(*typeIdentifierMap).isCompositeType());
return std::unique_ptr<StructInfo>(new StructInfo(module, structType, new DICompositeType(diEnvPtrType.getTypeDerivedFrom().resolve(*typeIdentifierMap)), typeIdentifierMap));
}
}
llvm::errs() << "WARNING: Debug information for struct CPUArchState not found" << '\n';
return nullptr;
}
// Retourne un objet value contenant un entier
Value* GlobalVariableGenerator::getIndexOfMember(Module *module, std::string name) {
LLVMContext &c = module->getContext();
Type *t;
GlobalVariable *g = module->getGlobalVariable(name);
t = Type::getInt32Ty(c)->getPointerTo();
if(g->getType() != t)
KawaUtilitary::stopGenerationIR(ERROR_UNKNOW_INDEX);
Value *v = new LoadInst(g);
return v;
}
bool AMDGPUPromoteAlloca::runOnFunction(Function &F) {
const FunctionType *FTy = F.getFunctionType();
LocalMemAvailable = ST.getLocalMemorySize();
// If the function has any arguments in the local address space, then it's
// possible these arguments require the entire local memory space, so
// we cannot use local memory in the pass.
for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i) {
const Type *ParamTy = FTy->getParamType(i);
if (ParamTy->isPointerTy() &&
ParamTy->getPointerAddressSpace() == AMDGPUAS::LOCAL_ADDRESS) {
LocalMemAvailable = 0;
DEBUG(dbgs() << "Function has local memory argument. Promoting to "
"local memory disabled.\n");
break;
}
}
if (LocalMemAvailable > 0) {
// Check how much local memory is being used by global objects
for (Module::global_iterator I = Mod->global_begin(),
E = Mod->global_end(); I != E; ++I) {
GlobalVariable *GV = I;
PointerType *GVTy = GV->getType();
if (GVTy->getAddressSpace() != AMDGPUAS::LOCAL_ADDRESS)
continue;
for (Value::use_iterator U = GV->use_begin(),
UE = GV->use_end(); U != UE; ++U) {
Instruction *Use = dyn_cast<Instruction>(*U);
if (!Use)
continue;
if (Use->getParent()->getParent() == &F)
LocalMemAvailable -=
Mod->getDataLayout()->getTypeAllocSize(GVTy->getElementType());
}
}
}
LocalMemAvailable = std::max(0, LocalMemAvailable);
DEBUG(dbgs() << LocalMemAvailable << "bytes free in local memory.\n");
visit(F);
return false;
}
static void setGlobalVariableValue(Module &M, const char *Name,
Constant *Value) {
GlobalVariable *Var = M.getNamedGlobal(Name);
if (!Var) {
// This warning can happen in a program that does not use a libc
// and does not initialize TLS variables. Such a program might be
// linked with "-nostdlib".
errs() << "Warning: Variable " << Name << " not referenced\n";
} else {
if (Var->hasInitializer()) {
report_fatal_error(std::string("Variable ") + Name +
" already has an initializer");
}
Var->replaceAllUsesWith(ConstantExpr::getBitCast(Value, Var->getType()));
Var->eraseFromParent();
}
}
bool RegisterGlobals::runOnModule(Module &M) {
TD = &getAnalysis<TargetData>();
VoidTy = Type::getVoidTy(M.getContext());
VoidPtrTy = Type::getInt8PtrTy(M.getContext());
SizeTy = IntegerType::getInt64Ty(M.getContext());
// Create the function prototype
M.getOrInsertFunction("__pool_register_global", VoidTy, VoidPtrTy, SizeTy,
NULL);
RegisterGlobalPoolFunction = M.getFunction("__pool_register_global");
// Create the function that will contain the registration calls
createRegistrationFunction(M);
Module::global_iterator GI = M.global_begin(), GE = M.global_end();
for ( ; GI != GE; ++GI) {
GlobalVariable *GV = GI;
// Skip globals without a size
if (!GV->getType()->getElementType()->isSized())
continue;
// Optionally avoid registering globals with uncertain size.
if (!RegUncertain) {
// Linking can change the size of declarations
if (GV->isDeclaration())
continue;
// Linking can't change the size of defined globals with eternal linkage.
// Linking can't change the size of globals with local linkage.
if (!GV->hasExternalLinkage() && !GV->hasLocalLinkage())
continue;
}
// Thread-local globals would have to be registered for each thread.
// FIXME: add support for thread-local globals
if (GV->isThreadLocal())
continue;
registerGlobal(GV);
}
return true;
}
Function *GCOVProfiler::
insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *FlushF = M->getFunction("__llvm_gcov_flush");
if (!FlushF)
FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
"__llvm_gcov_flush", M);
else
FlushF->setLinkage(GlobalValue::InternalLinkage);
FlushF->setUnnamedAddr(true);
FlushF->addFnAttr(Attribute::NoInline);
if (Options.NoRedZone)
FlushF->addFnAttr(Attribute::NoRedZone);
BasicBlock *Entry = BasicBlock::Create(*Ctx, "entry", FlushF);
// Write out the current counters.
Constant *WriteoutF = M->getFunction("__llvm_gcov_writeout");
assert(WriteoutF && "Need to create the writeout function first!");
IRBuilder<> Builder(Entry);
Builder.CreateCall(WriteoutF);
// Zero out the counters.
for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator
I = CountersBySP.begin(), E = CountersBySP.end();
I != E; ++I) {
GlobalVariable *GV = I->first;
Constant *Null = Constant::getNullValue(GV->getType()->getElementType());
Builder.CreateStore(Null, GV);
}
Type *RetTy = FlushF->getReturnType();
if (RetTy == Type::getVoidTy(*Ctx))
Builder.CreateRetVoid();
else if (RetTy->isIntegerTy())
// Used if __llvm_gcov_flush was implicitly declared.
Builder.CreateRet(ConstantInt::get(RetTy, 0));
else
report_fatal_error("invalid return type for __llvm_gcov_flush");
return FlushF;
}
/// getOrInsertGlobal - Look up the specified global in the module symbol table.
/// 1. If it does not exist, add a declaration of the global and return it.
/// 2. Else, the global exists but has the wrong type: return the function
/// with a constantexpr cast to the right type.
/// 3. Finally, if the existing global is the correct delclaration, return the
/// existing global.
Constant *Module::getOrInsertGlobal(StringRef Name, Type *Ty) {
// See if we have a definition for the specified global already.
GlobalVariable *GV = dyn_cast_or_null<GlobalVariable>(getNamedValue(Name));
if (GV == 0) {
// Nope, add it
GlobalVariable *New =
new GlobalVariable(*this, Ty, false, GlobalVariable::ExternalLinkage,
0, Name);
return New; // Return the new declaration.
}
// If the variable exists but has the wrong type, return a bitcast to the
// right type.
if (GV->getType() != PointerType::getUnqual(Ty))
return ConstantExpr::getBitCast(GV, PointerType::getUnqual(Ty));
// Otherwise, we just found the existing function or a prototype.
return GV;
}
void GCOVProfiler::
insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *FlushF = M->getFunction("__llvm_gcov_flush");
if (!FlushF)
FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
"__llvm_gcov_flush", M);
else
FlushF->setLinkage(GlobalValue::InternalLinkage);
FlushF->setUnnamedAddr(true);
Type *Int8Ty = Type::getInt8Ty(*Ctx);
Type *Int64Ty = Type::getInt64Ty(*Ctx);
BasicBlock *Entry = BasicBlock::Create(*Ctx, "entry", FlushF);
// Write out the current counters.
Constant *WriteoutF = M->getFunction("__llvm_gcov_writeout");
assert(WriteoutF && "Need to create the writeout function first!");
IRBuilder<> Builder(Entry);
Builder.CreateCall(WriteoutF);
if (TD)
// Zero out the counters.
for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator
I = CountersBySP.begin(), E = CountersBySP.end();
I != E; ++I) {
GlobalVariable *GV = I->first;
uint64_t NumBytes = TD->getTypeAllocSize(GV->getType()->getElementType());
Builder.CreateMemSet(Builder.CreateConstGEP2_64(GV, 0, 0),
ConstantInt::get(Int8Ty, 0),
ConstantInt::get(Int64Ty, NumBytes), false);
}
Type *RetTy = FlushF->getReturnType();
if (RetTy == Type::getVoidTy(*Ctx))
Builder.CreateRetVoid();
else if (RetTy->isIntegerTy())
// Used if __llvm_gcov_flush was implicitly declared.
Builder.CreateRet(ConstantInt::get(RetTy, 0));
else
report_fatal_error("invalid return type for __llvm_gcov_flush");
}
void Mapper::mapAppendingVariable(GlobalVariable &GV, Constant *InitPrefix,
bool IsOldCtorDtor,
ArrayRef<Constant *> NewMembers) {
SmallVector<Constant *, 16> Elements;
if (InitPrefix) {
unsigned NumElements =
cast<ArrayType>(InitPrefix->getType())->getNumElements();
for (unsigned I = 0; I != NumElements; ++I)
Elements.push_back(InitPrefix->getAggregateElement(I));
}
PointerType *VoidPtrTy;
Type *EltTy;
if (IsOldCtorDtor) {
// FIXME: This upgrade is done during linking to support the C API. See
// also IRLinker::linkAppendingVarProto() in IRMover.cpp.
VoidPtrTy = Type::getInt8Ty(GV.getContext())->getPointerTo();
auto &ST = *cast<StructType>(NewMembers.front()->getType());
Type *Tys[3] = {ST.getElementType(0), ST.getElementType(1), VoidPtrTy};
EltTy = StructType::get(GV.getContext(), Tys, false);
}
for (auto *V : NewMembers) {
Constant *NewV;
if (IsOldCtorDtor) {
auto *S = cast<ConstantStruct>(V);
auto *E1 = cast<Constant>(mapValue(S->getOperand(0)));
auto *E2 = cast<Constant>(mapValue(S->getOperand(1)));
Constant *Null = Constant::getNullValue(VoidPtrTy);
NewV = ConstantStruct::get(cast<StructType>(EltTy), E1, E2, Null);
} else {
NewV = cast_or_null<Constant>(mapValue(V));
}
Elements.push_back(NewV);
}
GV.setInitializer(ConstantArray::get(
cast<ArrayType>(GV.getType()->getElementType()), Elements));
}
void llvm::InsertProfilingShutdownCall(Function *Callee, Module *Mod) {
// llvm.global_dtors is an array of type { i32, void ()* }. Prepare those
// types.
Type *GlobalDtorElems[2] = {
Type::getInt32Ty(Mod->getContext()),
FunctionType::get(Type::getVoidTy(Mod->getContext()), false)->getPointerTo()
};
StructType *GlobalDtorElemTy =
StructType::get(Mod->getContext(), GlobalDtorElems, false);
// Construct the new element we'll be adding.
Constant *Elem[2] = {
ConstantInt::get(Type::getInt32Ty(Mod->getContext()), 65535),
ConstantExpr::getBitCast(Callee, GlobalDtorElems[1])
};
// If llvm.global_dtors exists, make a copy of the things in its list and
// delete it, to replace it with one that has a larger array type.
std::vector<Constant *> dtors;
if (GlobalVariable *GlobalDtors = Mod->getNamedGlobal("llvm.global_dtors")) {
if (ConstantArray *InitList =
dyn_cast<ConstantArray>(GlobalDtors->getInitializer())) {
for (unsigned i = 0, e = InitList->getType()->getNumElements();
i != e; ++i)
dtors.push_back(cast<Constant>(InitList->getOperand(i)));
}
GlobalDtors->eraseFromParent();
}
// Build up llvm.global_dtors with our new item in it.
GlobalVariable *GlobalDtors = new GlobalVariable(
*Mod, ArrayType::get(GlobalDtorElemTy, 1), false,
GlobalValue::AppendingLinkage, NULL, "llvm.global_dtors");
dtors.push_back(ConstantStruct::get(GlobalDtorElemTy, Elem));
GlobalDtors->setInitializer(ConstantArray::get(
cast<ArrayType>(GlobalDtors->getType()->getElementType()), dtors));
}
void PointerAnalysis::objectAnalysis()
{
llvm::DataLayout DL(module);
for (auto &globalVal: module->globals()) {
GlobalVariable *gv = dyn_cast<GlobalVariable>(&globalVal);
Type *gvt = gv->getType();
assert(gvt->isPointerTy());
globals.insert(gv);
globalBounds[gv] = sizeOf(gvt->getContainedType(0), DL);
}
Function *mainfp = module->getFunction("main");
if (mainfp == nullptr)
return;
ArgumentAttributes args( mainfp->arg_size() );
for (size_t i = 0; i < mainfp->arg_size(); i++) {
args[i] = UNBOUND_ATTR;
}
objectPass(mainfp, args);
}
//
// Method: runOnModule()
//
// Description:
// Entry point for this LLVM pass.
//
// Return value:
// true - The module was modified.
// false - The module was not modified.
//
bool
BreakConstantStrings::runOnModule (Module & M) {
bool modified = false;
const Type * Int8Type = IntegerType::getInt8Ty(getGlobalContext());
//
// Scan through all the global variables in the module. Mark a variable as
// non-constant if:
// o) The variable is constant
// o) The variable is an array of characters (Int8Ty).
// o) The variable is not in a special section (e.g. debug info section).
// This ensures that we don't mess up debug information or other special
// strings within the code.
//
Module::global_iterator i,e;
for (i = M.global_begin(), e = M.global_end(); i != e; ++i) {
GlobalVariable * GV = i;
//
// All global variables are pointer types. Find the type of what the
// global variable pointer is pointing at.
//
if (GV->isConstant() && (!GV->hasSection())) {
const PointerType * PT = dyn_cast<PointerType>(GV->getType());
if (const ArrayType * AT = dyn_cast<ArrayType>(PT->getElementType())) {
if (AT->getElementType() == Int8Type) {
modified = true;
++GVChanges;
GV->setConstant (false);
}
}
}
}
return modified;
}
void GCOVProfiler::insertCounterWriteout(
ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) {
FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
if (!WriteoutF)
WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage,
"__llvm_gcov_writeout", M);
WriteoutF->setUnnamedAddr(true);
WriteoutF->addFnAttr(Attribute::NoInline);
if (Options.NoRedZone)
WriteoutF->addFnAttr(Attribute::NoRedZone);
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
IRBuilder<> Builder(BB);
Constant *StartFile = getStartFileFunc();
Constant *EmitFunction = getEmitFunctionFunc();
Constant *EmitArcs = getEmitArcsFunc();
Constant *EndFile = getEndFileFunc();
NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
if (CU_Nodes) {
for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
DICompileUnit CU(CU_Nodes->getOperand(i));
std::string FilenameGcda = mangleName(CU, "gcda");
Builder.CreateCall2(StartFile,
Builder.CreateGlobalStringPtr(FilenameGcda),
Builder.CreateGlobalStringPtr(ReversedVersion));
for (unsigned j = 0, e = CountersBySP.size(); j != e; ++j) {
DISubprogram SP(CountersBySP[j].second);
Builder.CreateCall3(EmitFunction,
Builder.getInt32(j),
Options.FunctionNamesInData ?
Builder.CreateGlobalStringPtr(SP.getName()) :
Constant::getNullValue(Builder.getInt8PtrTy()),
Builder.getInt8(Options.UseCfgChecksum));
GlobalVariable *GV = CountersBySP[j].first;
unsigned Arcs =
cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
Builder.CreateCall2(EmitArcs,
Builder.getInt32(Arcs),
Builder.CreateConstGEP2_64(GV, 0, 0));
}
Builder.CreateCall(EndFile);
}
}
Builder.CreateRetVoid();
// Create a small bit of code that registers the "__llvm_gcov_writeout"
// function to be executed at exit.
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *F = Function::Create(FTy, GlobalValue::InternalLinkage,
"__llvm_gcov_init", M);
F->setUnnamedAddr(true);
F->setLinkage(GlobalValue::InternalLinkage);
F->addFnAttr(Attribute::NoInline);
if (Options.NoRedZone)
F->addFnAttr(Attribute::NoRedZone);
BB = BasicBlock::Create(*Ctx, "entry", F);
Builder.SetInsertPoint(BB);
FTy = FunctionType::get(Builder.getInt32Ty(),
PointerType::get(FTy, 0), false);
Constant *AtExitFn = M->getOrInsertFunction("atexit", FTy);
Builder.CreateCall(AtExitFn, WriteoutF);
Builder.CreateRetVoid();
appendToGlobalCtors(*M, F, 0);
}
void GCOVProfiler::insertCounterWriteout(
ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) {
FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
if (!WriteoutF)
WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage,
"__llvm_gcov_writeout", M);
WriteoutF->setUnnamedAddr(true);
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
IRBuilder<> Builder(BB);
Constant *StartFile = getStartFileFunc();
Constant *EmitFunction = getEmitFunctionFunc();
Constant *EmitArcs = getEmitArcsFunc();
Constant *EndFile = getEndFileFunc();
NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
if (CU_Nodes) {
for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
DICompileUnit compile_unit(CU_Nodes->getOperand(i));
std::string FilenameGcda = mangleName(compile_unit, "gcda");
Builder.CreateCall(StartFile,
Builder.CreateGlobalStringPtr(FilenameGcda));
for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator
I = CountersBySP.begin(), E = CountersBySP.end();
I != E; ++I) {
DISubprogram SP(I->second);
intptr_t ident = reinterpret_cast<intptr_t>(I->second);
Builder.CreateCall2(EmitFunction,
ConstantInt::get(Type::getInt32Ty(*Ctx), ident),
Builder.CreateGlobalStringPtr(SP.getName()));
GlobalVariable *GV = I->first;
unsigned Arcs =
cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
Builder.CreateCall2(EmitArcs,
ConstantInt::get(Type::getInt32Ty(*Ctx), Arcs),
Builder.CreateConstGEP2_64(GV, 0, 0));
}
Builder.CreateCall(EndFile);
}
}
Builder.CreateRetVoid();
// Create a small bit of code that registers the "__llvm_gcov_writeout"
// function to be executed at exit.
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *F = Function::Create(FTy, GlobalValue::InternalLinkage,
"__llvm_gcov_init", M);
F->setUnnamedAddr(true);
F->setLinkage(GlobalValue::InternalLinkage);
F->addFnAttr(Attribute::NoInline);
BB = BasicBlock::Create(*Ctx, "entry", F);
Builder.SetInsertPoint(BB);
FTy = FunctionType::get(Type::getInt32Ty(*Ctx),
PointerType::get(FTy, 0), false);
Constant *AtExitFn = M->getOrInsertFunction("atexit", FTy);
Builder.CreateCall(AtExitFn, WriteoutF);
Builder.CreateRetVoid();
appendToGlobalCtors(*M, F, 0);
}
bool AllocateDataSegment::runOnModule(Module &M) {
DataLayout DL(&M);
Type *I8 = Type::getInt8Ty(M.getContext());
Type *I32 = Type::getInt32Ty(M.getContext());
Type *IntPtrType = DL.getIntPtrType(M.getContext());
// First, we do a pass over the global variables, in which we compute
// the amount of required padding between them and consequently their
// addresses relative to the memory base of the sandbox. References to each
// global are then replaced with direct memory pointers.
uint32_t VarOffset = 0;
DenseMap<GlobalVariable*, uint32_t> VarPadding;
for (Module::global_iterator GV = M.global_begin(), E = M.global_end();
GV != E; ++GV) {
assert(GV->hasInitializer());
uint32_t Padding = getPadding(VarOffset, GV, DL);
VarPadding[GV] = Padding;
VarOffset += Padding;
GV->replaceAllUsesWith(
ConstantExpr::getIntToPtr(
ConstantInt::get(IntPtrType,
DataSegmentBaseAddress + VarOffset),
GV->getType()));
VarOffset += DL.getTypeStoreSize(GV->getType()->getPointerElementType());
}
// Using the offsets computed above, we prepare the layout and the contents
// of the desired data structure. After the type and initializer of each
// global is copied, the global is not needed any more and it is erased.
SmallVector<Type*, 10> TemplateLayout;
SmallVector<Constant*, 10> TemplateData;
for (Module::global_iterator It = M.global_begin(), E = M.global_end();
It != E; ) {
GlobalVariable *GV = It++;
uint32_t Padding = VarPadding[GV];
if (Padding > 0) {
Type *PaddingType = ArrayType::get(I8, Padding);
TemplateLayout.push_back(PaddingType);
TemplateData.push_back(ConstantAggregateZero::get(PaddingType));
}
TemplateLayout.push_back(GV->getType()->getPointerElementType());
TemplateData.push_back(GV->getInitializer());
GV->eraseFromParent();
}
// Finally, we create the struct and size global variables.
StructType *TemplateType =
StructType::create(M.getContext(), ExternalSymName_DataSegment);
TemplateType->setBody(TemplateLayout, /*isPacked=*/true);
Constant *Template = ConstantStruct::get(TemplateType, TemplateData);
new GlobalVariable(M, Template->getType(), /*isConstant=*/true,
GlobalVariable::ExternalLinkage, Template,
ExternalSymName_DataSegment);
Constant *TemplateSize =
ConstantInt::get(I32, DL.getTypeAllocSize(TemplateType));
new GlobalVariable(M, TemplateSize->getType(), /*isConstant=*/true,
GlobalVariable::ExternalLinkage, TemplateSize,
ExternalSymName_DataSegmentSize);
return true;
}
/// emit_global_to_llvm - Emit the specified VAR_DECL or aggregate CONST_DECL to
/// LLVM as a global variable. This function implements the end of
/// assemble_variable.
void emit_global_to_llvm(tree decl) {
if (errorcount || sorrycount) return;
// FIXME: Support alignment on globals: DECL_ALIGN.
// FIXME: DECL_PRESERVE_P indicates the var is marked with attribute 'used'.
// Global register variables don't turn into LLVM GlobalVariables.
if (TREE_CODE(decl) == VAR_DECL && DECL_REGISTER(decl))
return;
timevar_push(TV_LLVM_GLOBALS);
// Get or create the global variable now.
GlobalVariable *GV = cast<GlobalVariable>(DECL_LLVM(decl));
// Convert the initializer over.
Constant *Init;
if (DECL_INITIAL(decl) == 0 || DECL_INITIAL(decl) == error_mark_node) {
// This global should be zero initialized. Reconvert the type in case the
// forward def of the global and the real def differ in type (e.g. declared
// as 'int A[]', and defined as 'int A[100]').
Init = Constant::getNullValue(ConvertType(TREE_TYPE(decl)));
} else {
assert((TREE_CONSTANT(DECL_INITIAL(decl)) ||
TREE_CODE(DECL_INITIAL(decl)) == STRING_CST) &&
"Global initializer should be constant!");
// Temporarily set an initializer for the global, so we don't infinitely
// recurse. If we don't do this, we can hit cases where we see "oh a global
// with an initializer hasn't been initialized yet, call emit_global_to_llvm
// on it". When constructing the initializer it might refer to itself.
// this can happen for things like void *G = &G;
//
GV->setInitializer(UndefValue::get(GV->getType()->getElementType()));
Init = TreeConstantToLLVM::Convert(DECL_INITIAL(decl));
}
// If we had a forward definition that has a type that disagrees with our
// initializer, insert a cast now. This sort of thing occurs when we have a
// global union, and the LLVM type followed a union initializer that is
// different from the union element used for the type.
if (GV->getType()->getElementType() != Init->getType()) {
GV->removeFromParent();
GlobalVariable *NGV = new GlobalVariable(Init->getType(), GV->isConstant(),
GlobalValue::ExternalLinkage, 0,
GV->getName(), TheModule);
GV->replaceAllUsesWith(ConstantExpr::getBitCast(NGV, GV->getType()));
delete GV;
SET_DECL_LLVM(decl, NGV);
GV = NGV;
}
// Set the initializer.
GV->setInitializer(Init);
// Set thread local (TLS)
if (TREE_CODE(decl) == VAR_DECL && DECL_THREAD_LOCAL(decl))
GV->setThreadLocal(true);
// Set the linkage.
if (!TREE_PUBLIC(decl)) {
GV->setLinkage(GlobalValue::InternalLinkage);
} else if (DECL_WEAK(decl) || DECL_ONE_ONLY(decl) ||
(DECL_COMMON(decl) && // DECL_COMMON is only meaningful if no init
(!DECL_INITIAL(decl) || DECL_INITIAL(decl) == error_mark_node))) {
// llvm-gcc also includes DECL_VIRTUAL_P here.
GV->setLinkage(GlobalValue::WeakLinkage);
} else if (DECL_COMDAT(decl)) {
GV->setLinkage(GlobalValue::LinkOnceLinkage);
}
#ifdef TARGET_ADJUST_LLVM_LINKAGE
TARGET_ADJUST_LLVM_LINKAGE(GV,decl);
#endif /* TARGET_ADJUST_LLVM_LINKAGE */
// Handle visibility style
if (TREE_PUBLIC(decl)) {
if (DECL_VISIBILITY(decl) == VISIBILITY_HIDDEN)
GV->setVisibility(GlobalValue::HiddenVisibility);
else if (DECL_VISIBILITY(decl) == VISIBILITY_PROTECTED)
GV->setVisibility(GlobalValue::ProtectedVisibility);
}
// Set the section for the global.
if (TREE_CODE(decl) == VAR_DECL || TREE_CODE(decl) == CONST_DECL) {
if (DECL_SECTION_NAME(decl)) {
GV->setSection(TREE_STRING_POINTER(DECL_SECTION_NAME(decl)));
#ifdef LLVM_IMPLICIT_TARGET_GLOBAL_VAR_SECTION
} else if (const char *Section =
LLVM_IMPLICIT_TARGET_GLOBAL_VAR_SECTION(decl)) {
GV->setSection(Section);
#endif
}
// Set the alignment for the global if one of the following condition is met
// 1) DECL_ALIGN_UNIT does not match alignment as per ABI specification
// 2) DECL_ALIGN is set by user.
if (DECL_ALIGN_UNIT(decl)) {
unsigned TargetAlign = getTargetData().getABITypeAlignment(GV->getType()->getElementType());
if (DECL_USER_ALIGN(decl) || TargetAlign != DECL_ALIGN_UNIT(decl))
GV->setAlignment(DECL_ALIGN_UNIT(decl));
}
// Handle used decls
if (DECL_PRESERVE_P (decl)) {
const Type *SBP= PointerType::get(Type::Int8Ty);
AttributeUsedGlobals.push_back(ConstantExpr::getBitCast(GV, SBP));
}
// Add annotate attributes for globals
if (DECL_ATTRIBUTES(decl))
AddAnnotateAttrsToGlobal(GV, decl);
}
if (TheDebugInfo) TheDebugInfo->EmitGlobalVariable(GV, decl);
timevar_pop(TV_LLVM_GLOBALS);
}
bool ConstantMerge::runOnModule(Module &M) {
TD = getAnalysisIfAvailable<TargetData>();
// Find all the globals that are marked "used". These cannot be merged.
SmallPtrSet<const GlobalValue*, 8> UsedGlobals;
FindUsedValues(M.getGlobalVariable("llvm.used"), UsedGlobals);
FindUsedValues(M.getGlobalVariable("llvm.compiler.used"), UsedGlobals);
// Map unique <constants, has-unknown-alignment> pairs to globals. We don't
// want to merge globals of unknown alignment with those of explicit
// alignment. If we have TargetData, we always know the alignment.
DenseMap<PointerIntPair<Constant*, 1, bool>, GlobalVariable*> CMap;
// Replacements - This vector contains a list of replacements to perform.
SmallVector<std::pair<GlobalVariable*, GlobalVariable*>, 32> Replacements;
bool MadeChange = false;
// Iterate constant merging while we are still making progress. Merging two
// constants together may allow us to merge other constants together if the
// second level constants have initializers which point to the globals that
// were just merged.
while (1) {
// First: Find the canonical constants others will be merged with.
for (Module::global_iterator GVI = M.global_begin(), E = M.global_end();
GVI != E; ) {
GlobalVariable *GV = GVI++;
// If this GV is dead, remove it.
GV->removeDeadConstantUsers();
if (GV->use_empty() && GV->hasLocalLinkage()) {
GV->eraseFromParent();
continue;
}
// Only process constants with initializers in the default address space.
if (!GV->isConstant() || !GV->hasDefinitiveInitializer() ||
GV->getType()->getAddressSpace() != 0 || GV->hasSection() ||
// Don't touch values marked with attribute(used).
UsedGlobals.count(GV))
continue;
// This transformation is legal for weak ODR globals in the sense it
// doesn't change semantics, but we really don't want to perform it
// anyway; it's likely to pessimize code generation, and some tools
// (like the Darwin linker in cases involving CFString) don't expect it.
if (GV->isWeakForLinker())
continue;
Constant *Init = GV->getInitializer();
// Check to see if the initializer is already known.
PointerIntPair<Constant*, 1, bool> Pair(Init, hasKnownAlignment(GV));
GlobalVariable *&Slot = CMap[Pair];
// If this is the first constant we find or if the old one is local,
// replace with the current one. If the current is externally visible
// it cannot be replace, but can be the canonical constant we merge with.
if (Slot == 0 || IsBetterCannonical(*GV, *Slot))
Slot = GV;
}
// Second: identify all globals that can be merged together, filling in
// the Replacements vector. We cannot do the replacement in this pass
// because doing so may cause initializers of other globals to be rewritten,
// invalidating the Constant* pointers in CMap.
for (Module::global_iterator GVI = M.global_begin(), E = M.global_end();
GVI != E; ) {
GlobalVariable *GV = GVI++;
// Only process constants with initializers in the default address space.
if (!GV->isConstant() || !GV->hasDefinitiveInitializer() ||
GV->getType()->getAddressSpace() != 0 || GV->hasSection() ||
// Don't touch values marked with attribute(used).
UsedGlobals.count(GV))
continue;
// We can only replace constant with local linkage.
if (!GV->hasLocalLinkage())
continue;
Constant *Init = GV->getInitializer();
// Check to see if the initializer is already known.
PointerIntPair<Constant*, 1, bool> Pair(Init, hasKnownAlignment(GV));
GlobalVariable *Slot = CMap[Pair];
if (!Slot || Slot == GV)
continue;
if (!Slot->hasUnnamedAddr() && !GV->hasUnnamedAddr())
continue;
if (!GV->hasUnnamedAddr())
Slot->setUnnamedAddr(false);
// Make all uses of the duplicate constant use the canonical version.
Replacements.push_back(std::make_pair(GV, Slot));
}
if (Replacements.empty())
return MadeChange;
CMap.clear();
// Now that we have figured out which replacements must be made, do them all
// now. This avoid invalidating the pointers in CMap, which are unneeded
// now.
for (unsigned i = 0, e = Replacements.size(); i != e; ++i) {
// Bump the alignment if necessary.
if (Replacements[i].first->getAlignment() ||
Replacements[i].second->getAlignment()) {
Replacements[i].second->setAlignment(std::max(
Replacements[i].first->getAlignment(),
Replacements[i].second->getAlignment()));
}
// Eliminate any uses of the dead global.
Replacements[i].first->replaceAllUsesWith(Replacements[i].second);
// Delete the global value from the module.
assert(Replacements[i].first->hasLocalLinkage() &&
"Refusing to delete an externally visible global variable.");
Replacements[i].first->eraseFromParent();
}
NumMerged += Replacements.size();
Replacements.clear();
}
}
// This function replaces all global variables with new variables that have
// trailing redzones. It also creates a function that poisons
// redzones and inserts this function into llvm.global_ctors.
bool AddressSanitizer::insertGlobalRedzones(Module &M) {
SmallVector<GlobalVariable *, 16> GlobalsToChange;
for (Module::GlobalListType::iterator G = M.getGlobalList().begin(),
E = M.getGlobalList().end(); G != E; ++G) {
Type *Ty = cast<PointerType>(G->getType())->getElementType();
DEBUG(dbgs() << "GLOBAL: " << *G);
if (!Ty->isSized()) continue;
if (!G->hasInitializer()) continue;
// Touch only those globals that will not be defined in other modules.
// Don't handle ODR type linkages since other modules may be built w/o asan.
if (G->getLinkage() != GlobalVariable::ExternalLinkage &&
G->getLinkage() != GlobalVariable::PrivateLinkage &&
G->getLinkage() != GlobalVariable::InternalLinkage)
continue;
// Two problems with thread-locals:
// - The address of the main thread's copy can't be computed at link-time.
// - Need to poison all copies, not just the main thread's one.
if (G->isThreadLocal())
continue;
// For now, just ignore this Alloca if the alignment is large.
if (G->getAlignment() > RedzoneSize) continue;
// Ignore all the globals with the names starting with "\01L_OBJC_".
// Many of those are put into the .cstring section. The linker compresses
// that section by removing the spare \0s after the string terminator, so
// our redzones get broken.
if ((G->getName().find("\01L_OBJC_") == 0) ||
(G->getName().find("\01l_OBJC_") == 0)) {
DEBUG(dbgs() << "Ignoring \\01L_OBJC_* global: " << *G);
continue;
}
if (G->hasSection()) {
StringRef Section(G->getSection());
// Ignore the globals from the __OBJC section. The ObjC runtime assumes
// those conform to /usr/lib/objc/runtime.h, so we can't add redzones to
// them.
if ((Section.find("__OBJC,") == 0) ||
(Section.find("__DATA, __objc_") == 0)) {
DEBUG(dbgs() << "Ignoring ObjC runtime global: " << *G);
continue;
}
// See http://code.google.com/p/address-sanitizer/issues/detail?id=32
// Constant CFString instances are compiled in the following way:
// -- the string buffer is emitted into
// __TEXT,__cstring,cstring_literals
// -- the constant NSConstantString structure referencing that buffer
// is placed into __DATA,__cfstring
// Therefore there's no point in placing redzones into __DATA,__cfstring.
// Moreover, it causes the linker to crash on OS X 10.7
if (Section.find("__DATA,__cfstring") == 0) {
DEBUG(dbgs() << "Ignoring CFString: " << *G);
continue;
}
}
GlobalsToChange.push_back(G);
}
size_t n = GlobalsToChange.size();
if (n == 0) return false;
// A global is described by a structure
// size_t beg;
// size_t size;
// size_t size_with_redzone;
// const char *name;
// We initialize an array of such structures and pass it to a run-time call.
StructType *GlobalStructTy = StructType::get(IntptrTy, IntptrTy,
IntptrTy, IntptrTy, NULL);
SmallVector<Constant *, 16> Initializers(n);
IRBuilder<> IRB(CtorInsertBefore);
for (size_t i = 0; i < n; i++) {
GlobalVariable *G = GlobalsToChange[i];
PointerType *PtrTy = cast<PointerType>(G->getType());
Type *Ty = PtrTy->getElementType();
uint64_t SizeInBytes = TD->getTypeStoreSizeInBits(Ty) / 8;
uint64_t RightRedzoneSize = RedzoneSize +
(RedzoneSize - (SizeInBytes % RedzoneSize));
Type *RightRedZoneTy = ArrayType::get(IRB.getInt8Ty(), RightRedzoneSize);
StructType *NewTy = StructType::get(Ty, RightRedZoneTy, NULL);
Constant *NewInitializer = ConstantStruct::get(
NewTy, G->getInitializer(),
Constant::getNullValue(RightRedZoneTy), NULL);
SmallString<2048> DescriptionOfGlobal = G->getName();
DescriptionOfGlobal += " (";
DescriptionOfGlobal += M.getModuleIdentifier();
DescriptionOfGlobal += ")";
GlobalVariable *Name = createPrivateGlobalForString(M, DescriptionOfGlobal);
// Create a new global variable with enough space for a redzone.
GlobalVariable *NewGlobal = new GlobalVariable(
M, NewTy, G->isConstant(), G->getLinkage(),
NewInitializer, "", G, G->isThreadLocal());
NewGlobal->copyAttributesFrom(G);
NewGlobal->setAlignment(RedzoneSize);
Value *Indices2[2];
Indices2[0] = IRB.getInt32(0);
Indices2[1] = IRB.getInt32(0);
G->replaceAllUsesWith(
ConstantExpr::getGetElementPtr(NewGlobal, Indices2, true));
NewGlobal->takeName(G);
G->eraseFromParent();
Initializers[i] = ConstantStruct::get(
GlobalStructTy,
ConstantExpr::getPointerCast(NewGlobal, IntptrTy),
ConstantInt::get(IntptrTy, SizeInBytes),
ConstantInt::get(IntptrTy, SizeInBytes + RightRedzoneSize),
ConstantExpr::getPointerCast(Name, IntptrTy),
NULL);
DEBUG(dbgs() << "NEW GLOBAL:\n" << *NewGlobal);
}
ArrayType *ArrayOfGlobalStructTy = ArrayType::get(GlobalStructTy, n);
GlobalVariable *AllGlobals = new GlobalVariable(
M, ArrayOfGlobalStructTy, false, GlobalVariable::PrivateLinkage,
ConstantArray::get(ArrayOfGlobalStructTy, Initializers), "");
Function *AsanRegisterGlobals = cast<Function>(M.getOrInsertFunction(
kAsanRegisterGlobalsName, IRB.getVoidTy(), IntptrTy, IntptrTy, NULL));
AsanRegisterGlobals->setLinkage(Function::ExternalLinkage);
IRB.CreateCall2(AsanRegisterGlobals,
IRB.CreatePointerCast(AllGlobals, IntptrTy),
ConstantInt::get(IntptrTy, n));
// We also need to unregister globals at the end, e.g. when a shared library
// gets closed.
Function *AsanDtorFunction = Function::Create(
FunctionType::get(Type::getVoidTy(*C), false),
GlobalValue::InternalLinkage, kAsanModuleDtorName, &M);
BasicBlock *AsanDtorBB = BasicBlock::Create(*C, "", AsanDtorFunction);
IRBuilder<> IRB_Dtor(ReturnInst::Create(*C, AsanDtorBB));
Function *AsanUnregisterGlobals = cast<Function>(M.getOrInsertFunction(
kAsanUnregisterGlobalsName, IRB.getVoidTy(), IntptrTy, IntptrTy, NULL));
AsanUnregisterGlobals->setLinkage(Function::ExternalLinkage);
IRB_Dtor.CreateCall2(AsanUnregisterGlobals,
IRB.CreatePointerCast(AllGlobals, IntptrTy),
ConstantInt::get(IntptrTy, n));
appendToGlobalDtors(M, AsanDtorFunction, kAsanCtorAndCtorPriority);
DEBUG(dbgs() << M);
return true;
}
std::unique_ptr<StructInfo> StructInfo::getFromGlobalPointer(Module *module, llvm::StringRef name)
{
GlobalVariable *var = module->getGlobalVariable(name, false);
if (!var || !var->getType() || !var->getType()->isPointerTy()) {
assert(false);
llvm::errs() << "StructInfo: Cannot get global variable " << name << ", or it is not a pointer." << '\n';
return nullptr;
}
PointerType *varDeref = dyn_cast<PointerType>(var->getType()->getElementType());
if (!varDeref || !varDeref->getElementType())
{
assert(false);
llvm::errs() << "StructInfo: Pointer not valid." << '\n';
return nullptr;
}
StructType *structType = dyn_cast<StructType>(varDeref->getElementType());
if (!structType) {
assert(false);
llvm::errs() << "StructInfo: Cannot get struct type." << '\n';
return nullptr;
}
NamedMDNode *mdCuNodes = module->getNamedMetadata("llvm.dbg.cu");
if (!mdCuNodes) {
assert(false);
llvm::errs() << "StructInfo: Cannot find metadata." << '\n';
return nullptr;
}
std::shared_ptr<DITypeIdentifierMap> typeIdentifierMap(new DITypeIdentifierMap(generateDITypeIdentifierMap(mdCuNodes)));
DICompositeType *diStructType = nullptr;
for ( unsigned i = 0; i < mdCuNodes->getNumOperands() && !diStructType; ++i )
{
DICompileUnit diCu(mdCuNodes->getOperand(i));
for ( unsigned j = 0; j < diCu.getGlobalVariables().getNumElements(); ++j )
{
DIGlobalVariable diGlobalVar(diCu.getGlobalVariables().getElement(j));
if (diGlobalVar.getName() != name) {
continue;
}
//Go through pointers until we reach a structure
DIType diStructType(diGlobalVar.getType());
while (diStructType.isDerivedType() && !diStructType.isCompositeType()) {
diStructType = std::unique_ptr<DIDerivedType>(new DIDerivedType(diStructType))->getTypeDerivedFrom().resolve(*typeIdentifierMap);
}
if (!diStructType.isCompositeType()) {
llvm::errs() << "StructInfo: Global variable " << name << " does not point to a composite type: " << diStructType.getName() << '\n';
assert(false);
return nullptr;
}
return std::unique_ptr<StructInfo>(new StructInfo(
module,
structType,
new DICompositeType(diStructType),
typeIdentifierMap));
}
}
assert(false);
llvm::errs() << "StructInfo: Did not find global variable " << name << " in debug information." << '\n';
return nullptr;
}
// This function replaces all global variables with new variables that have
// trailing redzones. It also creates a function that poisons
// redzones and inserts this function into llvm.global_ctors.
bool AddressSanitizer::insertGlobalRedzones(Module &M) {
SmallVector<GlobalVariable *, 16> GlobalsToChange;
for (Module::GlobalListType::iterator G = M.global_begin(),
E = M.global_end(); G != E; ++G) {
if (ShouldInstrumentGlobal(G))
GlobalsToChange.push_back(G);
}
size_t n = GlobalsToChange.size();
if (n == 0) return false;
// A global is described by a structure
// size_t beg;
// size_t size;
// size_t size_with_redzone;
// const char *name;
// size_t has_dynamic_init;
// We initialize an array of such structures and pass it to a run-time call.
StructType *GlobalStructTy = StructType::get(IntptrTy, IntptrTy,
IntptrTy, IntptrTy,
IntptrTy, NULL);
SmallVector<Constant *, 16> Initializers(n), DynamicInit;
IRBuilder<> IRB(CtorInsertBefore);
if (ClInitializers)
FindDynamicInitializers(M);
// The addresses of the first and last dynamically initialized globals in
// this TU. Used in initialization order checking.
Value *FirstDynamic = 0, *LastDynamic = 0;
for (size_t i = 0; i < n; i++) {
GlobalVariable *G = GlobalsToChange[i];
PointerType *PtrTy = cast<PointerType>(G->getType());
Type *Ty = PtrTy->getElementType();
uint64_t SizeInBytes = TD->getTypeAllocSize(Ty);
uint64_t RightRedzoneSize = RedzoneSize +
(RedzoneSize - (SizeInBytes % RedzoneSize));
Type *RightRedZoneTy = ArrayType::get(IRB.getInt8Ty(), RightRedzoneSize);
// Determine whether this global should be poisoned in initialization.
bool GlobalHasDynamicInitializer = HasDynamicInitializer(G);
// Don't check initialization order if this global is blacklisted.
GlobalHasDynamicInitializer &= !BL->isInInit(*G);
StructType *NewTy = StructType::get(Ty, RightRedZoneTy, NULL);
Constant *NewInitializer = ConstantStruct::get(
NewTy, G->getInitializer(),
Constant::getNullValue(RightRedZoneTy), NULL);
SmallString<2048> DescriptionOfGlobal = G->getName();
DescriptionOfGlobal += " (";
DescriptionOfGlobal += M.getModuleIdentifier();
DescriptionOfGlobal += ")";
GlobalVariable *Name = createPrivateGlobalForString(M, DescriptionOfGlobal);
// Create a new global variable with enough space for a redzone.
GlobalVariable *NewGlobal = new GlobalVariable(
M, NewTy, G->isConstant(), G->getLinkage(),
NewInitializer, "", G, G->getThreadLocalMode());
NewGlobal->copyAttributesFrom(G);
NewGlobal->setAlignment(RedzoneSize);
Value *Indices2[2];
Indices2[0] = IRB.getInt32(0);
Indices2[1] = IRB.getInt32(0);
G->replaceAllUsesWith(
ConstantExpr::getGetElementPtr(NewGlobal, Indices2, true));
NewGlobal->takeName(G);
G->eraseFromParent();
Initializers[i] = ConstantStruct::get(
GlobalStructTy,
ConstantExpr::getPointerCast(NewGlobal, IntptrTy),
ConstantInt::get(IntptrTy, SizeInBytes),
ConstantInt::get(IntptrTy, SizeInBytes + RightRedzoneSize),
ConstantExpr::getPointerCast(Name, IntptrTy),
ConstantInt::get(IntptrTy, GlobalHasDynamicInitializer),
NULL);
// Populate the first and last globals declared in this TU.
if (ClInitializers && GlobalHasDynamicInitializer) {
LastDynamic = ConstantExpr::getPointerCast(NewGlobal, IntptrTy);
if (FirstDynamic == 0)
FirstDynamic = LastDynamic;
}
DEBUG(dbgs() << "NEW GLOBAL:\n" << *NewGlobal);
}
ArrayType *ArrayOfGlobalStructTy = ArrayType::get(GlobalStructTy, n);
GlobalVariable *AllGlobals = new GlobalVariable(
M, ArrayOfGlobalStructTy, false, GlobalVariable::PrivateLinkage,
ConstantArray::get(ArrayOfGlobalStructTy, Initializers), "");
// Create calls for poisoning before initializers run and unpoisoning after.
if (ClInitializers && FirstDynamic && LastDynamic)
createInitializerPoisonCalls(M, FirstDynamic, LastDynamic);
Function *AsanRegisterGlobals = checkInterfaceFunction(M.getOrInsertFunction(
kAsanRegisterGlobalsName, IRB.getVoidTy(),
IntptrTy, IntptrTy, NULL));
AsanRegisterGlobals->setLinkage(Function::ExternalLinkage);
IRB.CreateCall2(AsanRegisterGlobals,
IRB.CreatePointerCast(AllGlobals, IntptrTy),
ConstantInt::get(IntptrTy, n));
// We also need to unregister globals at the end, e.g. when a shared library
// gets closed.
Function *AsanDtorFunction = Function::Create(
FunctionType::get(Type::getVoidTy(*C), false),
GlobalValue::InternalLinkage, kAsanModuleDtorName, &M);
BasicBlock *AsanDtorBB = BasicBlock::Create(*C, "", AsanDtorFunction);
IRBuilder<> IRB_Dtor(ReturnInst::Create(*C, AsanDtorBB));
Function *AsanUnregisterGlobals =
checkInterfaceFunction(M.getOrInsertFunction(
kAsanUnregisterGlobalsName,
IRB.getVoidTy(), IntptrTy, IntptrTy, NULL));
AsanUnregisterGlobals->setLinkage(Function::ExternalLinkage);
IRB_Dtor.CreateCall2(AsanUnregisterGlobals,
IRB.CreatePointerCast(AllGlobals, IntptrTy),
ConstantInt::get(IntptrTy, n));
appendToGlobalDtors(M, AsanDtorFunction, kAsanCtorAndCtorPriority);
DEBUG(dbgs() << M);
return true;
}
bool GenericToNVVM::runOnModule(Module &M) {
// Create a clone of each global variable that has the default address space.
// The clone is created with the global address space specifier, and the pair
// of original global variable and its clone is placed in the GVMap for later
// use.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E;) {
GlobalVariable *GV = &*I++;
if (GV->getType()->getAddressSpace() == llvm::ADDRESS_SPACE_GENERIC &&
!llvm::isTexture(*GV) && !llvm::isSurface(*GV) &&
!llvm::isSampler(*GV) && !GV->getName().startswith("llvm.")) {
GlobalVariable *NewGV = new GlobalVariable(
M, GV->getValueType(), GV->isConstant(),
GV->getLinkage(),
GV->hasInitializer() ? GV->getInitializer() : nullptr,
"", GV, GV->getThreadLocalMode(), llvm::ADDRESS_SPACE_GLOBAL);
NewGV->copyAttributesFrom(GV);
GVMap[GV] = NewGV;
}
}
// Return immediately, if every global variable has a specific address space
// specifier.
if (GVMap.empty()) {
return false;
}
// Walk through the instructions in function defitinions, and replace any use
// of original global variables in GVMap with a use of the corresponding
// copies in GVMap. If necessary, promote constants to instructions.
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
if (I->isDeclaration()) {
continue;
}
IRBuilder<> Builder(I->getEntryBlock().getFirstNonPHIOrDbg());
for (Function::iterator BBI = I->begin(), BBE = I->end(); BBI != BBE;
++BBI) {
for (BasicBlock::iterator II = BBI->begin(), IE = BBI->end(); II != IE;
++II) {
for (unsigned i = 0, e = II->getNumOperands(); i < e; ++i) {
Value *Operand = II->getOperand(i);
if (isa<Constant>(Operand)) {
II->setOperand(
i, remapConstant(&M, &*I, cast<Constant>(Operand), Builder));
}
}
}
}
ConstantToValueMap.clear();
}
// Copy GVMap over to a standard value map.
ValueToValueMapTy VM;
for (auto I = GVMap.begin(), E = GVMap.end(); I != E; ++I)
VM[I->first] = I->second;
// Walk through the metadata section and update the debug information
// associated with the global variables in the default address space.
for (NamedMDNode &I : M.named_metadata()) {
remapNamedMDNode(VM, &I);
}
// Walk through the global variable initializers, and replace any use of
// original global variables in GVMap with a use of the corresponding copies
// in GVMap. The copies need to be bitcast to the original global variable
// types, as we cannot use cvta in global variable initializers.
for (GVMapTy::iterator I = GVMap.begin(), E = GVMap.end(); I != E;) {
GlobalVariable *GV = I->first;
GlobalVariable *NewGV = I->second;
// Remove GV from the map so that it can be RAUWed. Note that
// DenseMap::erase() won't invalidate any iterators but this one.
auto Next = std::next(I);
GVMap.erase(I);
I = Next;
Constant *BitCastNewGV = ConstantExpr::getPointerCast(NewGV, GV->getType());
// At this point, the remaining uses of GV should be found only in global
// variable initializers, as other uses have been already been removed
// while walking through the instructions in function definitions.
GV->replaceAllUsesWith(BitCastNewGV);
std::string Name = GV->getName();
GV->eraseFromParent();
NewGV->setName(Name);
}
assert(GVMap.empty() && "Expected it to be empty by now");
return true;
}
GlobalVariable *
InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) {
GlobalVariable *Name = Inc->getName();
auto It = RegionCounters.find(Name);
if (It != RegionCounters.end())
return It->second;
// Move the name variable to the right section. Place them in a COMDAT group
// if the associated function is a COMDAT. This will make sure that
// only one copy of counters of the COMDAT function will be emitted after
// linking.
Function *Fn = Inc->getParent()->getParent();
Comdat *ProfileVarsComdat = nullptr;
if (Fn->hasComdat())
ProfileVarsComdat = M->getOrInsertComdat(StringRef(getVarName(Inc, "vars")));
Name->setSection(getNameSection());
Name->setAlignment(1);
Name->setComdat(ProfileVarsComdat);
uint64_t NumCounters = Inc->getNumCounters()->getZExtValue();
LLVMContext &Ctx = M->getContext();
ArrayType *CounterTy = ArrayType::get(Type::getInt64Ty(Ctx), NumCounters);
// Create the counters variable.
auto *Counters = new GlobalVariable(*M, CounterTy, false, Name->getLinkage(),
Constant::getNullValue(CounterTy),
getVarName(Inc, "counters"));
Counters->setVisibility(Name->getVisibility());
Counters->setSection(getCountersSection());
Counters->setAlignment(8);
Counters->setComdat(ProfileVarsComdat);
RegionCounters[Inc->getName()] = Counters;
// Create data variable.
auto *NameArrayTy = Name->getType()->getPointerElementType();
auto *Int32Ty = Type::getInt32Ty(Ctx);
auto *Int64Ty = Type::getInt64Ty(Ctx);
auto *Int8PtrTy = Type::getInt8PtrTy(Ctx);
auto *Int64PtrTy = Type::getInt64PtrTy(Ctx);
Type *DataTypes[] = {Int32Ty, Int32Ty, Int64Ty, Int8PtrTy, Int64PtrTy};
auto *DataTy = StructType::get(Ctx, makeArrayRef(DataTypes));
Constant *DataVals[] = {
ConstantInt::get(Int32Ty, NameArrayTy->getArrayNumElements()),
ConstantInt::get(Int32Ty, NumCounters),
ConstantInt::get(Int64Ty, Inc->getHash()->getZExtValue()),
ConstantExpr::getBitCast(Name, Int8PtrTy),
ConstantExpr::getBitCast(Counters, Int64PtrTy)};
auto *Data = new GlobalVariable(*M, DataTy, true, Name->getLinkage(),
ConstantStruct::get(DataTy, DataVals),
getVarName(Inc, "data"));
Data->setVisibility(Name->getVisibility());
Data->setSection(getDataSection());
Data->setAlignment(8);
Data->setComdat(ProfileVarsComdat);
// Mark the data variable as used so that it isn't stripped out.
UsedVars.push_back(Data);
return Counters;
}
void SMT12Writer::declareGlobalVariable(const GlobalVariable & v) {
m_out << ":extrafuns ((" << NameDecorator<Value>(&v)
<< " " << NameDecorator<Type>(v.getType()) << "))\n";
}
bool ConstantMerge::runOnModule(Module &M) {
// Find all the globals that are marked "used". These cannot be merged.
SmallPtrSet<const GlobalValue*, 8> UsedGlobals;
FindUsedValues(M.getGlobalVariable("llvm.used"), UsedGlobals);
FindUsedValues(M.getGlobalVariable("llvm.compiler.used"), UsedGlobals);
// Map unique constant/section pairs to globals. We don't want to merge
// globals in different sections.
DenseMap<Constant*, GlobalVariable*> CMap;
// Replacements - This vector contains a list of replacements to perform.
SmallVector<std::pair<GlobalVariable*, GlobalVariable*>, 32> Replacements;
bool MadeChange = false;
// Iterate constant merging while we are still making progress. Merging two
// constants together may allow us to merge other constants together if the
// second level constants have initializers which point to the globals that
// were just merged.
while (1) {
// First pass: identify all globals that can be merged together, filling in
// the Replacements vector. We cannot do the replacement in this pass
// because doing so may cause initializers of other globals to be rewritten,
// invalidating the Constant* pointers in CMap.
//
for (Module::global_iterator GVI = M.global_begin(), E = M.global_end();
GVI != E; ) {
GlobalVariable *GV = GVI++;
// If this GV is dead, remove it.
GV->removeDeadConstantUsers();
if (GV->use_empty() && GV->hasLocalLinkage()) {
GV->eraseFromParent();
continue;
}
// Only process constants with initializers in the default addres space.
if (!GV->isConstant() ||!GV->hasDefinitiveInitializer() ||
GV->getType()->getAddressSpace() != 0 || !GV->getSection().empty() ||
// Don't touch values marked with attribute(used).
UsedGlobals.count(GV))
continue;
Constant *Init = GV->getInitializer();
// Check to see if the initializer is already known.
GlobalVariable *&Slot = CMap[Init];
if (Slot == 0) { // Nope, add it to the map.
Slot = GV;
} else if (GV->hasLocalLinkage()) { // Yup, this is a duplicate!
// Make all uses of the duplicate constant use the canonical version.
Replacements.push_back(std::make_pair(GV, Slot));
}
}
if (Replacements.empty())
return MadeChange;
CMap.clear();
// Now that we have figured out which replacements must be made, do them all
// now. This avoid invalidating the pointers in CMap, which are unneeded
// now.
for (unsigned i = 0, e = Replacements.size(); i != e; ++i) {
// Eliminate any uses of the dead global.
Replacements[i].first->replaceAllUsesWith(Replacements[i].second);
// Delete the global value from the module.
Replacements[i].first->eraseFromParent();
}
NumMerged += Replacements.size();
Replacements.clear();
}
}
//
// Method: runOnModule()
//
// Description:
// Entry point for this pass.
//
bool
Dyncount::runOnModule (Module & M) {
//
// Create two global counters within the module.
//
TS = &getAnalysis<dsa::TypeSafety<TDDataStructures> >();
ConstantInt * Zero = ConstantInt::get (Type::getInt64Ty(M.getContext()), 0);
GlobalVariable * Total = new GlobalVariable (M,
Type::getInt64Ty(M.getContext()),
false,
GlobalValue::InternalLinkage,
Zero,
"Total");
GlobalVariable * Safe = new GlobalVariable (M,
Type::getInt64Ty(M.getContext()),
false,
GlobalValue::InternalLinkage,
Zero,
"Safe");
for (Module::iterator F = M.begin(); F != M.end(); ++F){
for (Function::iterator B = F->begin(), FE = F->end(); B != FE; ++B) {
for (BasicBlock::iterator I = B->begin(), BE = B->end(); I != BE; I++) {
if(LoadInst *LI = dyn_cast<LoadInst>(I)) {
instrumentLoad(Total, LI);
if(TS->isTypeSafe(LI->getOperand(0),LI->getParent()->getParent()))
instrumentLoad(Safe, LI);
// check if safe
} else if(StoreInst *SI = dyn_cast<StoreInst>(I)) {
instrumentStore(Total, SI);
if(TS->isTypeSafe(SI->getOperand(1),SI->getParent()->getParent()))
instrumentStore(Safe, SI);
// check if safe
}
}
}
}
//
// Add a call to main() that will record the values on exit().
//
Function *MainFunc = M.getFunction("main") ? M.getFunction("main")
: M.getFunction ("MAIN__");
BasicBlock & BB = MainFunc->getEntryBlock();
Constant * Setup = M.getOrInsertFunction ("DYN_COUNT_setup", Type::getVoidTy(M.getContext()), Total->getType(), Safe->getType(), NULL);
std::vector<Value *> args;
args.push_back (Total);
args.push_back (Safe);
CallInst::Create (Setup, args, "", BB.getFirstNonPHI());
return true;
}
virtual bool runOnFunction(Function &F) {
//F.dump();
bool changed = false;
for (inst_iterator inst_it = inst_begin(F), _inst_end = inst_end(F); inst_it != _inst_end; ++inst_it) {
LoadInst *li = dyn_cast<LoadInst>(&*inst_it);
if (!li) continue;
ConstantExpr *ce = dyn_cast<ConstantExpr>(li->getOperand(0));
// Not 100% sure what the isGEPWithNoNotionalOverIndexing() means, but
// at least it checks if it's a gep:
if (ce && ce->isGEPWithNoNotionalOverIndexing() && ce->getOperand(0)->getType() == g.llvm_flavor_type_ptr) {
changed = handleFlavor(li, ce);
}
GlobalVariable *gv = dyn_cast<GlobalVariable>(li->getOperand(0));
if (!gv) continue;
llvm::Type* gv_t = gv->getType();
if (gv_t == g.llvm_bool_type_ptr->getPointerTo()) {
changed = handleBool(li, gv) || changed;
continue;
}
if (gv_t == g.llvm_class_type_ptr->getPointerTo()) {
changed = handleCls(li, gv) || changed;
continue;
}
}
return changed;
}
