void InstrProfiling::emitUses() {
if (UsedVars.empty())
return;
GlobalVariable *LLVMUsed = M->getGlobalVariable("llvm.used");
std::vector<Constant *> MergedVars;
if (LLVMUsed) {
// Collect the existing members of llvm.used.
ConstantArray *Inits = cast<ConstantArray>(LLVMUsed->getInitializer());
for (unsigned I = 0, E = Inits->getNumOperands(); I != E; ++I)
MergedVars.push_back(Inits->getOperand(I));
LLVMUsed->eraseFromParent();
}
Type *i8PTy = Type::getInt8PtrTy(M->getContext());
// Add uses for our data.
for (auto *Value : UsedVars)
MergedVars.push_back(
ConstantExpr::getBitCast(cast<Constant>(Value), i8PTy));
// Recreate llvm.used.
ArrayType *ATy = ArrayType::get(i8PTy, MergedVars.size());
LLVMUsed =
new GlobalVariable(*M, ATy, false, GlobalValue::AppendingLinkage,
ConstantArray::get(ATy, MergedVars), "llvm.used");
LLVMUsed->setSection("llvm.metadata");
}
bool StripDeadPrototypesPass::runOnModule(Module &M) {
bool MadeChange = false;
// Erase dead function prototypes.
for (Module::iterator I = M.begin(), E = M.end(); I != E; ) {
Function *F = I++;
// Function must be a prototype and unused.
if (F->isDeclaration() && F->use_empty()) {
F->eraseFromParent();
++NumDeadPrototypes;
MadeChange = true;
}
}
// Erase dead global var prototypes.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ) {
GlobalVariable *GV = I++;
// Global must be a prototype and unused.
if (GV->isDeclaration() && GV->use_empty())
GV->eraseFromParent();
}
// Return an indication of whether we changed anything or not.
return MadeChange;
}
void LTOCodeGenerator::applyScopeRestrictions() {
if (ScopeRestrictionsDone || !ShouldInternalize)
return;
Module *mergedModule = IRLinker.getModule();
// Start off with a verification pass.
legacy::PassManager passes;
passes.add(createVerifierPass());
// mark which symbols can not be internalized
Mangler Mangler(TargetMach->getDataLayout());
std::vector<const char*> MustPreserveList;
SmallPtrSet<GlobalValue*, 8> AsmUsed;
std::vector<StringRef> Libcalls;
TargetLibraryInfoImpl TLII(Triple(TargetMach->getTargetTriple()));
TargetLibraryInfo TLI(TLII);
accumulateAndSortLibcalls(Libcalls, TLI, *mergedModule, *TargetMach);
for (Module::iterator f = mergedModule->begin(),
e = mergedModule->end(); f != e; ++f)
applyRestriction(*f, Libcalls, MustPreserveList, AsmUsed, Mangler);
for (Module::global_iterator v = mergedModule->global_begin(),
e = mergedModule->global_end(); v != e; ++v)
applyRestriction(*v, Libcalls, MustPreserveList, AsmUsed, Mangler);
for (Module::alias_iterator a = mergedModule->alias_begin(),
e = mergedModule->alias_end(); a != e; ++a)
applyRestriction(*a, Libcalls, MustPreserveList, AsmUsed, Mangler);
GlobalVariable *LLVMCompilerUsed =
mergedModule->getGlobalVariable("llvm.compiler.used");
findUsedValues(LLVMCompilerUsed, AsmUsed);
if (LLVMCompilerUsed)
LLVMCompilerUsed->eraseFromParent();
if (!AsmUsed.empty()) {
llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(Context);
std::vector<Constant*> asmUsed2;
for (auto *GV : AsmUsed) {
Constant *c = ConstantExpr::getBitCast(GV, i8PTy);
asmUsed2.push_back(c);
}
llvm::ArrayType *ATy = llvm::ArrayType::get(i8PTy, asmUsed2.size());
LLVMCompilerUsed =
new llvm::GlobalVariable(*mergedModule, ATy, false,
llvm::GlobalValue::AppendingLinkage,
llvm::ConstantArray::get(ATy, asmUsed2),
"llvm.compiler.used");
LLVMCompilerUsed->setSection("llvm.metadata");
}
passes.add(createInternalizePass(MustPreserveList));
// apply scope restrictions
passes.run(*mergedModule);
ScopeRestrictionsDone = true;
}
void LTOCodeGenerator::applyScopeRestrictions() {
if (ScopeRestrictionsDone)
return;
Module *mergedModule = Linker.getModule();
// Start off with a verification pass.
PassManager passes;
passes.add(createVerifierPass());
// mark which symbols can not be internalized
MCContext MContext(TargetMach->getMCAsmInfo(), TargetMach->getRegisterInfo(),
NULL);
Mangler Mangler(MContext, TargetMach);
std::vector<const char*> MustPreserveList;
SmallPtrSet<GlobalValue*, 8> AsmUsed;
for (Module::iterator f = mergedModule->begin(),
e = mergedModule->end(); f != e; ++f)
applyRestriction(*f, MustPreserveList, AsmUsed, Mangler);
for (Module::global_iterator v = mergedModule->global_begin(),
e = mergedModule->global_end(); v != e; ++v)
applyRestriction(*v, MustPreserveList, AsmUsed, Mangler);
for (Module::alias_iterator a = mergedModule->alias_begin(),
e = mergedModule->alias_end(); a != e; ++a)
applyRestriction(*a, MustPreserveList, AsmUsed, Mangler);
GlobalVariable *LLVMCompilerUsed =
mergedModule->getGlobalVariable("llvm.compiler.used");
findUsedValues(LLVMCompilerUsed, AsmUsed);
if (LLVMCompilerUsed)
LLVMCompilerUsed->eraseFromParent();
if (!AsmUsed.empty()) {
llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(Context);
std::vector<Constant*> asmUsed2;
for (SmallPtrSet<GlobalValue*, 16>::const_iterator i = AsmUsed.begin(),
e = AsmUsed.end(); i !=e; ++i) {
GlobalValue *GV = *i;
Constant *c = ConstantExpr::getBitCast(GV, i8PTy);
asmUsed2.push_back(c);
}
llvm::ArrayType *ATy = llvm::ArrayType::get(i8PTy, asmUsed2.size());
LLVMCompilerUsed =
new llvm::GlobalVariable(*mergedModule, ATy, false,
llvm::GlobalValue::AppendingLinkage,
llvm::ConstantArray::get(ATy, asmUsed2),
"llvm.compiler.used");
LLVMCompilerUsed->setSection("llvm.metadata");
}
passes.add(createInternalizePass(MustPreserveList));
// apply scope restrictions
passes.run(*mergedModule);
ScopeRestrictionsDone = true;
}
void LTOCodeGenerator::applyScopeRestrictions() {
if (_scopeRestrictionsDone) return;
Module *mergedModule = _linker.getModule();
// Start off with a verification pass.
PassManager passes;
passes.add(createVerifierPass());
// mark which symbols can not be internalized
MCContext Context(*_target->getMCAsmInfo(), *_target->getRegisterInfo(),NULL);
Mangler mangler(Context, *_target->getTargetData());
std::vector<const char*> mustPreserveList;
SmallPtrSet<GlobalValue*, 8> asmUsed;
for (Module::iterator f = mergedModule->begin(),
e = mergedModule->end(); f != e; ++f)
applyRestriction(*f, mustPreserveList, asmUsed, mangler);
for (Module::global_iterator v = mergedModule->global_begin(),
e = mergedModule->global_end(); v != e; ++v)
applyRestriction(*v, mustPreserveList, asmUsed, mangler);
for (Module::alias_iterator a = mergedModule->alias_begin(),
e = mergedModule->alias_end(); a != e; ++a)
applyRestriction(*a, mustPreserveList, asmUsed, mangler);
GlobalVariable *LLVMCompilerUsed =
mergedModule->getGlobalVariable("llvm.compiler.used");
findUsedValues(LLVMCompilerUsed, asmUsed);
if (LLVMCompilerUsed)
LLVMCompilerUsed->eraseFromParent();
llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(_context);
std::vector<Constant*> asmUsed2;
for (SmallPtrSet<GlobalValue*, 16>::const_iterator i = asmUsed.begin(),
e = asmUsed.end(); i !=e; ++i) {
GlobalValue *GV = *i;
Constant *c = ConstantExpr::getBitCast(GV, i8PTy);
asmUsed2.push_back(c);
}
llvm::ArrayType *ATy = llvm::ArrayType::get(i8PTy, asmUsed2.size());
LLVMCompilerUsed =
new llvm::GlobalVariable(*mergedModule, ATy, false,
llvm::GlobalValue::AppendingLinkage,
llvm::ConstantArray::get(ATy, asmUsed2),
"llvm.compiler.used");
LLVMCompilerUsed->setSection("llvm.metadata");
// Add prerequisite passes needed by SAFECode
PassManagerBuilder().populateLTOPassManager(passes, /*Internalize=*/ false,
!DisableInline);
passes.add(createInternalizePass(mustPreserveList));
// apply scope restrictions
passes.run(*mergedModule);
_scopeRestrictionsDone = true;
}
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();
}
}
static void defineFuncArray(Module &M, const char *LlvmArrayName,
const char *StartSymbol,
const char *EndSymbol) {
std::vector<Constant*> Funcs;
GlobalVariable *Array = M.getNamedGlobal(LlvmArrayName);
if (Array) {
readFuncList(Array, &Funcs);
// No code should be referencing global_ctors/global_dtors,
// because this symbol is internal to LLVM.
Array->eraseFromParent();
}
Type *FuncTy = FunctionType::get(Type::getVoidTy(M.getContext()), false);
Type *FuncPtrTy = FuncTy->getPointerTo();
ArrayType *ArrayTy = ArrayType::get(FuncPtrTy, Funcs.size());
GlobalVariable *NewArray =
new GlobalVariable(M, ArrayTy, /* isConstant= */ true,
GlobalValue::InternalLinkage,
ConstantArray::get(ArrayTy, Funcs));
setGlobalVariableValue(M, StartSymbol, NewArray);
// We do this last so that LLVM gives NewArray the name
// "__{init,fini}_array_start" without adding any suffixes to
// disambiguate from the original GlobalVariable's name. This is
// not essential -- it just makes the output easier to understand
// when looking at symbols for debugging.
NewArray->setName(StartSymbol);
// We replace "__{init,fini}_array_end" with the address of the end
// of NewArray. This removes the name "__{init,fini}_array_end"
// from the output, which is not ideal for debugging. Ideally we
// would convert "__{init,fini}_array_end" to being a GlobalAlias
// that points to the end of the array. However, unfortunately LLVM
// does not generate correct code when a GlobalAlias contains a
// GetElementPtr ConstantExpr.
Constant *NewArrayEnd =
ConstantExpr::getGetElementPtr(ArrayTy, NewArray,
ConstantInt::get(M.getContext(),
APInt(32, 1)));
setGlobalVariableValue(M, EndSymbol, NewArrayEnd);
}
void MemoryInstrumenter::lowerGlobalCtors(Module &M) {
// Find llvm.global_ctors.
GlobalVariable *GV = M.getNamedGlobal("llvm.global_ctors");
if (!GV)
return;
assert(!GV->isDeclaration() && !GV->hasLocalLinkage());
// Should be an array of '{ int, void ()* }' structs. The first value is
// the init priority, which must be 65535 if the bitcode is generated using
// clang.
if (ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer())) {
for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
ConstantStruct *CS =
dyn_cast<ConstantStruct>(InitList->getOperand(i));
assert(CS);
assert(CS->getNumOperands() == 2);
// Get the priority.
ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
assert(Priority);
// TODO: For now, we assume all priorities must be 65535.
assert(Priority->equalsInt(65535));
// Get the constructor function.
Constant *FP = CS->getOperand(1);
if (FP->isNullValue())
break; // Found a null terminator, exit.
// Explicitly call the constructor at the main entry.
CallInst::Create(FP, "", Main->begin()->getFirstNonPHI());
}
}
// Clear the global_ctors array.
// Use eraseFromParent() instead of removeFromParent().
GV->eraseFromParent();
}
void PerfMonitor::addToGlobalConstructors(Function *Fn) {
const char *Name = "llvm.global_ctors";
GlobalVariable *GV = M->getGlobalVariable(Name);
std::vector<Constant *> V;
if (GV) {
Constant *Array = GV->getInitializer();
for (Value *X : Array->operand_values())
V.push_back(cast<Constant>(X));
GV->eraseFromParent();
}
StructType *ST = StructType::get(Builder.getInt32Ty(), Fn->getType(),
Builder.getInt8PtrTy());
V.push_back(
ConstantStruct::get(ST, Builder.getInt32(10), Fn,
ConstantPointerNull::get(Builder.getInt8PtrTy())));
ArrayType *Ty = ArrayType::get(ST, V.size());
GV = new GlobalVariable(*M, Ty, true, GlobalValue::AppendingLinkage,
ConstantArray::get(Ty, V), Name, nullptr,
GlobalVariable::NotThreadLocal);
}
void InitializeSoftBound:: constructCheckHandlers(Module & module){
Type* void_ty = Type::getVoidTy(module.getContext());
Type* void_ptr_ty = PointerType::getUnqual(Type::getInt8Ty(module.getContext()));
Type* size_ty = Type::getInt64Ty(module.getContext());
module.getOrInsertFunction("__softboundcets_spatial_load_dereference_check",
void_ty, void_ptr_ty, void_ptr_ty,
void_ptr_ty, size_ty, NULL);
module.getOrInsertFunction("__softboundcets_spatial_store_dereference_check",
void_ty, void_ptr_ty, void_ptr_ty,
void_ptr_ty, size_ty, NULL);
module.getOrInsertFunction("__softboundcets_temporal_load_dereference_check",
void_ty, void_ptr_ty, size_ty,
void_ptr_ty, void_ptr_ty, NULL);
module.getOrInsertFunction("__softboundcets_temporal_store_dereference_check",
void_ty, void_ptr_ty, size_ty,
void_ptr_ty, void_ptr_ty, NULL);
Function* global_init = (Function *) module.getOrInsertFunction("__softboundcets_global_init",
void_ty, NULL);
global_init->setDoesNotThrow();
global_init->setLinkage(GlobalValue::InternalLinkage);
BasicBlock* BB = BasicBlock::Create(module.getContext(),
"entry", global_init);
Function* softboundcets_init = (Function*) module.getOrInsertFunction("__softboundcets_init", void_ty, Type::getInt32Ty(module.getContext()), NULL);
SmallVector<Value*, 8> args;
Constant * const_one = ConstantInt::get(Type::getInt32Ty(module.getContext()), 1);
args.push_back(const_one);
Instruction* ret = ReturnInst::Create(module.getContext(), BB);
CallInst::Create(softboundcets_init, args, "", ret);
Type * Int32Type = IntegerType::getInt32Ty(module.getContext());
std::vector<Constant *> CtorInits;
CtorInits.push_back(ConstantInt::get(Int32Type, 0));
CtorInits.push_back(global_init);
StructType * ST = ConstantStruct::getTypeForElements(CtorInits, false);
Constant * RuntimeCtorInit = ConstantStruct::get(ST, CtorInits);
//
// Get the current set of static global constructors and add the new ctor
// to the list.
//
std::vector<Constant *> CurrentCtors;
GlobalVariable * GVCtor = module.getNamedGlobal ("llvm.global_ctors");
if (GVCtor) {
if (Constant * C = GVCtor->getInitializer()) {
for (unsigned index = 0; index < C->getNumOperands(); ++index) {
CurrentCtors.push_back (dyn_cast<Constant>(C->getOperand (index)));
}
}
}
CurrentCtors.push_back(RuntimeCtorInit);
//
// Create a new initializer.
//
ArrayType * AT = ArrayType::get (RuntimeCtorInit-> getType(),
CurrentCtors.size());
Constant * NewInit = ConstantArray::get (AT, CurrentCtors);
//
// Create the new llvm.global_ctors global variable and remove the old one
// if it existed.
//
Value * newGVCtor = new GlobalVariable (module,
NewInit->getType(),
false,
GlobalValue::AppendingLinkage,
NewInit,
"llvm.global_ctors");
if (GVCtor) {
newGVCtor->takeName (GVCtor);
GVCtor->eraseFromParent ();
}
}
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;
}
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();
}
}
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;
}
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;
}
// With -fembed-bitcode, save a copy of the llvm IR as data in the
// __LLVM,__bitcode section.
void clang::EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
llvm::MemoryBufferRef Buf) {
if (CGOpts.getEmbedBitcode() == CodeGenOptions::Embed_Off)
return;
// Save llvm.compiler.used and remote it.
SmallVector<Constant*, 2> UsedArray;
SmallSet<GlobalValue*, 4> UsedGlobals;
Type *UsedElementType = Type::getInt8Ty(M->getContext())->getPointerTo(0);
GlobalVariable *Used = collectUsedGlobalVariables(*M, UsedGlobals, true);
for (auto *GV : UsedGlobals) {
if (GV->getName() != "llvm.embedded.module" &&
GV->getName() != "llvm.cmdline")
UsedArray.push_back(
ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
}
if (Used)
Used->eraseFromParent();
// Embed the bitcode for the llvm module.
std::string Data;
ArrayRef<uint8_t> ModuleData;
Triple T(M->getTargetTriple());
// Create a constant that contains the bitcode.
// In case of embedding a marker, ignore the input Buf and use the empty
// ArrayRef. It is also legal to create a bitcode marker even Buf is empty.
if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Marker) {
if (!isBitcode((const unsigned char *)Buf.getBufferStart(),
(const unsigned char *)Buf.getBufferEnd())) {
// If the input is LLVM Assembly, bitcode is produced by serializing
// the module. Use-lists order need to be perserved in this case.
llvm::raw_string_ostream OS(Data);
llvm::WriteBitcodeToFile(M, OS, /* ShouldPreserveUseListOrder */ true);
ModuleData =
ArrayRef<uint8_t>((const uint8_t *)OS.str().data(), OS.str().size());
} else
// If the input is LLVM bitcode, write the input byte stream directly.
ModuleData = ArrayRef<uint8_t>((const uint8_t *)Buf.getBufferStart(),
Buf.getBufferSize());
}
llvm::Constant *ModuleConstant =
llvm::ConstantDataArray::get(M->getContext(), ModuleData);
llvm::GlobalVariable *GV = new llvm::GlobalVariable(
*M, ModuleConstant->getType(), true, llvm::GlobalValue::PrivateLinkage,
ModuleConstant);
GV->setSection(getSectionNameForBitcode(T));
UsedArray.push_back(
ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
if (llvm::GlobalVariable *Old =
M->getGlobalVariable("llvm.embedded.module", true)) {
assert(Old->hasOneUse() &&
"llvm.embedded.module can only be used once in llvm.compiler.used");
GV->takeName(Old);
Old->eraseFromParent();
} else {
GV->setName("llvm.embedded.module");
}
// Skip if only bitcode needs to be embedded.
if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Bitcode) {
// Embed command-line options.
ArrayRef<uint8_t> CmdData(const_cast<uint8_t *>(CGOpts.CmdArgs.data()),
CGOpts.CmdArgs.size());
llvm::Constant *CmdConstant =
llvm::ConstantDataArray::get(M->getContext(), CmdData);
GV = new llvm::GlobalVariable(*M, CmdConstant->getType(), true,
llvm::GlobalValue::PrivateLinkage,
CmdConstant);
GV->setSection(getSectionNameForCommandline(T));
UsedArray.push_back(
ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
if (llvm::GlobalVariable *Old =
M->getGlobalVariable("llvm.cmdline", true)) {
assert(Old->hasOneUse() &&
"llvm.cmdline can only be used once in llvm.compiler.used");
GV->takeName(Old);
Old->eraseFromParent();
} else {
GV->setName("llvm.cmdline");
}
}
if (UsedArray.empty())
return;
// Recreate llvm.compiler.used.
ArrayType *ATy = ArrayType::get(UsedElementType, UsedArray.size());
auto *NewUsed = new GlobalVariable(
*M, ATy, false, llvm::GlobalValue::AppendingLinkage,
llvm::ConstantArray::get(ATy, UsedArray), "llvm.compiler.used");
NewUsed->setSection("llvm.metadata");
}
// 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;
}
// destructively move the contents of src into dest
// this assumes that the targets of the two modules are the same
// including the DataLayout and ModuleFlags (for example)
// and that there is no module-level assembly
static void jl_merge_module(Module *dest, std::unique_ptr<Module> src)
{
assert(dest != src.get());
for (Module::global_iterator I = src->global_begin(), E = src->global_end(); I != E;) {
GlobalVariable *sG = &*I;
GlobalValue *dG = dest->getNamedValue(sG->getName());
++I;
// Replace a declaration with the definition:
if (dG) {
if (sG->isDeclaration()) {
sG->replaceAllUsesWith(dG);
sG->eraseFromParent();
continue;
}
else {
dG->replaceAllUsesWith(sG);
dG->eraseFromParent();
}
}
// Reparent the global variable:
sG->removeFromParent();
dest->getGlobalList().push_back(sG);
// Comdat is owned by the Module, recreate it in the new parent:
addComdat(sG);
}
for (Module::iterator I = src->begin(), E = src->end(); I != E;) {
Function *sG = &*I;
GlobalValue *dG = dest->getNamedValue(sG->getName());
++I;
// Replace a declaration with the definition:
if (dG) {
if (sG->isDeclaration()) {
sG->replaceAllUsesWith(dG);
sG->eraseFromParent();
continue;
}
else {
dG->replaceAllUsesWith(sG);
dG->eraseFromParent();
}
}
// Reparent the global variable:
sG->removeFromParent();
dest->getFunctionList().push_back(sG);
// Comdat is owned by the Module, recreate it in the new parent:
addComdat(sG);
}
for (Module::alias_iterator I = src->alias_begin(), E = src->alias_end(); I != E;) {
GlobalAlias *sG = &*I;
GlobalValue *dG = dest->getNamedValue(sG->getName());
++I;
if (dG) {
if (!dG->isDeclaration()) { // aliases are always definitions, so this test is reversed from the above two
sG->replaceAllUsesWith(dG);
sG->eraseFromParent();
continue;
}
else {
dG->replaceAllUsesWith(sG);
dG->eraseFromParent();
}
}
sG->removeFromParent();
dest->getAliasList().push_back(sG);
}
// metadata nodes need to be explicitly merged not just copied
// so there are special passes here for each known type of metadata
NamedMDNode *sNMD = src->getNamedMetadata("llvm.dbg.cu");
if (sNMD) {
NamedMDNode *dNMD = dest->getOrInsertNamedMetadata("llvm.dbg.cu");
#ifdef LLVM35
for (NamedMDNode::op_iterator I = sNMD->op_begin(), E = sNMD->op_end(); I != E; ++I) {
dNMD->addOperand(*I);
}
#else
for (unsigned i = 0, l = sNMD->getNumOperands(); i < l; i++) {
dNMD->addOperand(sNMD->getOperand(i));
}
#endif
}
}
void HeterotbbTransform::rewrite_CPP(Module &M) {
// Collect initial set of hetero functions
vector<Instruction *> toDelete;
DenseMap<Function*, Function *> FunctionMap[2];
templat = NULL;
templat_join = NULL;
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
//if (isa<UnaryInst>(I))
if (!I->isDeclaration()) {
//DEBUG(dbgs() << "Func"<<*I<<"\n\n");
for (Function::iterator BBI = I->begin(), BBE = I->end(); BBI != BBE; ++BBI) {
for (BasicBlock::iterator INSNI = BBI->begin(), INSNE = BBI->end(); INSNI != INSNE; ++INSNI) {
if (isa<CallInst>(INSNI) || isa<InvokeInst>(INSNI)) {
//DEBUG(dbgs()<<*INSNI<<"\n");
CallSite CI(cast<Instruction>(INSNI));
// errs()<<"INS"<<INSNI<<"\n";
if (CI.getCalledFunction() == NULL) continue;
int type =0;
type = is_hetero_function_f(M, CI);//return a 1 for parallel_for and 2 for parallel_reduce
if (type) {
//CI->dump();
DEBUG(dbgs() << type<<":Hetero_fun "<<CI.getCalledFunction()->getName()<<"\n");
//get the kernel body
Function *f= get_hetero_func(M,CI);
//@_ZNK12diff_testingclEi
if(f!=NULL)//should never be null if the body is called.
{
DEBUG(dbgs() << " Kernel: "<<f->getName()<<"\n");
//create new function for the kernel
Function *nf=NULL;
if(FunctionMap[type-1].find(f)==FunctionMap[type-1].end()) {
nf = write_new_hetero_kernel(M,f,type);
FunctionMap[type-1][f]=nf;
DEBUG(dbgs() << " New Kernel Created: "<<nf->getName()<<" created\n\n");
/* Added by Raj to add inline attributes recursively*/
add_inline_attributes(nf);
}
else {
nf=FunctionMap[type-1][f];
DEBUG(dbgs() << " Kernel Exists: "<<nf->getName()<<" created\n\n");
}
//rewrite the hetero call site to offload
if(isa<CallInst>(INSNI))
rewrite_call_site(M,CI,nf,type);
else if(isa<InvokeInst>(INSNI)) //must be invoke
rewrite_invoke_site(M,CI,nf,type);
else {
DEBUG(dbgs()<<"ERROR\n");
}
//delete the old call site
toDelete.push_back(INSNI);
}
else {
DEBUG(dbgs() << " Parallel for/reduce hetero do not call any functions\n\n");
}
}
/*
#ifdef HETERO_GCD_H
else if(hetero_function = get_hetero_function(M, CI)) {
entry_hetero_function_set.insert(hetero_function);
#ifdef HETERO_GCD_ALLOC_TO_MALLOC
block2insnMap.insert(pair<Function *, Instruction *>(hetero_function, INSNI));
#endif
}
#endif
*/
}
}
}
}
}
while(!toDelete.empty()) {
Instruction *g = toDelete.back();
toDelete.pop_back();
// g->replaceAllUsesWith(UndefValue::get(g->getType()));
g->eraseFromParent();
}
/* delete the template functions */
if (templat_join != NULL) {
templat_join->replaceAllUsesWith(UndefValue::get(templat_join->getType()));
templat_join->eraseFromParent();
}
if (templat != NULL) {
templat->replaceAllUsesWith(UndefValue::get(templat->getType()));
templat->eraseFromParent();
}
//erase the annotation
GlobalVariable *annot = M.getGlobalVariable("opencl_metadata");
if (annot != NULL) annot->eraseFromParent();
annot = M.getGlobalVariable("opencl_metadata_type");
if (annot != NULL) annot->eraseFromParent();
annot = M.getGlobalVariable("opencl_kernel_join_name_locals");
if (annot != NULL) annot->eraseFromParent();
annot = M.getGlobalVariable("opencl_kernel_join_name_parameters");
if (annot != NULL) annot->eraseFromParent();
annot = M.getGlobalVariable("opencl_kernel_join_name_local_arr");
if (annot != NULL) annot->eraseFromParent();
}
