/// StripSymbolNames - Strip symbol names.
static bool StripSymbolNames(Module &M, bool PreserveDbgInfo) {
SmallPtrSet<const GlobalValue*, 8> llvmUsedValues;
findUsedValues(M.getGlobalVariable("llvm.used"), llvmUsedValues);
findUsedValues(M.getGlobalVariable("llvm.compiler.used"), llvmUsedValues);
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
if (I->hasLocalLinkage() && llvmUsedValues.count(I) == 0)
if (!PreserveDbgInfo || !I->getName().startswith("llvm.dbg"))
I->setName(""); // Internal symbols can't participate in linkage
}
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
if (I->hasLocalLinkage() && llvmUsedValues.count(I) == 0)
if (!PreserveDbgInfo || !I->getName().startswith("llvm.dbg"))
I->setName(""); // Internal symbols can't participate in linkage
StripSymtab(I->getValueSymbolTable(), PreserveDbgInfo);
}
// Remove all names from types.
StripTypeSymtab(M.getTypeSymbolTable(), PreserveDbgInfo);
return true;
}
/// AnalyzeGlobals - Scan through the users of all of the internal
/// GlobalValue's in the program. If none of them have their "address taken"
/// (really, their address passed to something nontrivial), record this fact,
/// and record the functions that they are used directly in.
void GlobalsModRef::AnalyzeGlobals(Module &M) {
std::vector<Function*> Readers, Writers;
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (I->hasLocalLinkage()) {
if (!AnalyzeUsesOfPointer(I, Readers, Writers)) {
// Remember that we are tracking this global.
NonAddressTakenGlobals.insert(I);
++NumNonAddrTakenFunctions;
}
Readers.clear(); Writers.clear();
}
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I)
if (I->hasLocalLinkage()) {
if (!AnalyzeUsesOfPointer(I, Readers, Writers)) {
// Remember that we are tracking this global, and the mod/ref fns
NonAddressTakenGlobals.insert(I);
for (unsigned i = 0, e = Readers.size(); i != e; ++i)
FunctionInfo[Readers[i]].GlobalInfo[I] |= Ref;
if (!I->isConstant()) // No need to keep track of writers to constants
for (unsigned i = 0, e = Writers.size(); i != e; ++i)
FunctionInfo[Writers[i]].GlobalInfo[I] |= Mod;
++NumNonAddrTakenGlobalVars;
// If this global holds a pointer type, see if it is an indirect global.
if (I->getType()->getElementType()->isPointerTy() &&
AnalyzeIndirectGlobalMemory(I))
++NumIndirectGlobalVars;
}
Readers.clear(); Writers.clear();
}
}
bool GlobalMerge::doInitialization(Module &M) {
DenseMap<unsigned, SmallVector<GlobalVariable*, 16> > Globals, ConstGlobals,
BSSGlobals;
const DataLayout *TD = TLI->getDataLayout();
unsigned MaxOffset = TLI->getMaximalGlobalOffset();
bool Changed = false;
// Grab all non-const globals.
for (Module::global_iterator I = M.global_begin(),
E = M.global_end(); I != E; ++I) {
// Merge is safe for "normal" internal globals only
if (!I->hasLocalLinkage() || I->isThreadLocal() || I->hasSection())
continue;
PointerType *PT = dyn_cast<PointerType>(I->getType());
assert(PT && "Global variable is not a pointer!");
unsigned AddressSpace = PT->getAddressSpace();
// Ignore fancy-aligned globals for now.
unsigned Alignment = TD->getPreferredAlignment(I);
Type *Ty = I->getType()->getElementType();
if (Alignment > TD->getABITypeAlignment(Ty))
continue;
// Ignore all 'special' globals.
if (I->getName().startswith("llvm.") ||
I->getName().startswith(".llvm."))
continue;
if (TD->getTypeAllocSize(Ty) < MaxOffset) {
if (TargetLoweringObjectFile::getKindForGlobal(I, TLI->getTargetMachine())
.isBSSLocal())
BSSGlobals[AddressSpace].push_back(I);
else if (I->isConstant())
ConstGlobals[AddressSpace].push_back(I);
else
Globals[AddressSpace].push_back(I);
}
}
for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
I = Globals.begin(), E = Globals.end(); I != E; ++I)
if (I->second.size() > 1)
Changed |= doMerge(I->second, M, false, I->first);
for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
I = BSSGlobals.begin(), E = BSSGlobals.end(); I != E; ++I)
if (I->second.size() > 1)
Changed |= doMerge(I->second, M, false, I->first);
// FIXME: This currently breaks the EH processing due to way how the
// typeinfo detection works. We might want to detect the TIs and ignore
// them in the future.
// if (ConstGlobals.size() > 1)
// Changed |= doMerge(ConstGlobals, M, true);
return Changed;
}
bool ARMGlobalMerge::doInitialization(Module &M) {
SmallVector<GlobalVariable*, 16> Globals, ConstGlobals, BSSGlobals;
const TargetData *TD = TLI->getTargetData();
unsigned MaxOffset = TLI->getMaximalGlobalOffset();
bool Changed = false;
// Disable this pass on darwin. The debugger is not yet ready to extract
// variable's info from a merged global.
if (TLI->getTargetMachine().getSubtarget<ARMSubtarget>().isTargetDarwin())
return false;
// Grab all non-const globals.
for (Module::global_iterator I = M.global_begin(),
E = M.global_end(); I != E; ++I) {
// Merge is safe for "normal" internal globals only
if (!I->hasLocalLinkage() || I->isThreadLocal() || I->hasSection())
continue;
// Ignore fancy-aligned globals for now.
if (I->getAlignment() != 0)
continue;
// Ignore all 'special' globals.
if (I->getName().startswith("llvm.") ||
I->getName().startswith(".llvm."))
continue;
if (TD->getTypeAllocSize(I->getType()->getElementType()) < MaxOffset) {
const TargetLoweringObjectFile &TLOF = TLI->getObjFileLowering();
if (TLOF.getKindForGlobal(I, TLI->getTargetMachine()).isBSSLocal())
BSSGlobals.push_back(I);
else if (I->isConstant())
ConstGlobals.push_back(I);
else
Globals.push_back(I);
}
}
if (Globals.size() > 1)
Changed |= doMerge(Globals, M, false);
if (BSSGlobals.size() > 1)
Changed |= doMerge(BSSGlobals, M, false);
// FIXME: This currently breaks the EH processing due to way how the
// typeinfo detection works. We might want to detect the TIs and ignore
// them in the future.
// if (ConstGlobals.size() > 1)
// Changed |= doMerge(ConstGlobals, M, true);
return Changed;
}
/// GetAllUndefinedSymbols - calculates the set of undefined symbols that still
/// exist in an LLVM module. This is a bit tricky because there may be two
/// symbols with the same name but different LLVM types that will be resolved to
/// each other but aren't currently (thus we need to treat it as resolved).
///
/// Inputs:
/// M - The module in which to find undefined symbols.
///
/// Outputs:
/// UndefinedSymbols - A set of C++ strings containing the name of all
/// undefined symbols.
///
static void
GetAllUndefinedSymbols(Module *M, std::set<std::string> &UndefinedSymbols) {
std::set<std::string> DefinedSymbols;
UndefinedSymbols.clear();
// If the program doesn't define a main, try pulling one in from a .a file.
// This is needed for programs where the main function is defined in an
// archive, such f2c'd programs.
Function *Main = M->getFunction("main");
if (Main == 0 || Main->isDeclaration())
UndefinedSymbols.insert("main");
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
if (I->hasName()) {
if (I->isDeclaration())
UndefinedSymbols.insert(I->getName());
else if (!I->hasLocalLinkage()) {
assert(!I->hasDLLImportLinkage()
&& "Found dllimported non-external symbol!");
DefinedSymbols.insert(I->getName());
}
}
for (Module::global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I)
if (I->hasName()) {
if (I->isDeclaration())
UndefinedSymbols.insert(I->getName());
else if (!I->hasLocalLinkage()) {
assert(!I->hasDLLImportLinkage()
&& "Found dllimported non-external symbol!");
DefinedSymbols.insert(I->getName());
}
}
for (Module::alias_iterator I = M->alias_begin(), E = M->alias_end();
I != E; ++I)
if (I->hasName())
DefinedSymbols.insert(I->getName());
// Prune out any defined symbols from the undefined symbols set...
for (std::set<std::string>::iterator I = UndefinedSymbols.begin();
I != UndefinedSymbols.end(); )
if (DefinedSymbols.count(*I))
UndefinedSymbols.erase(I++); // This symbol really is defined!
else
++I; // Keep this symbol in the undefined symbols list
}
void
AndroidBitcodeLinker::GetAllSymbols(Module *M,
std::set<std::string> &UndefinedSymbols,
std::set<std::string> &DefinedSymbols) {
UndefinedSymbols.clear();
DefinedSymbols.clear();
Function *Main = M->getFunction("main");
if (Main == 0 || Main->isDeclaration())
UndefinedSymbols.insert("main");
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
if (I->hasName()) {
if (I->isDeclaration())
UndefinedSymbols.insert(I->getName());
else if (!I->hasLocalLinkage()) {
assert(!I->hasDLLImportStorageClass()
&& "Found dllimported non-external symbol!");
DefinedSymbols.insert(I->getName());
}
}
for (Module::global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I)
if (I->hasName()) {
if (I->isDeclaration())
UndefinedSymbols.insert(I->getName());
else if (!I->hasLocalLinkage()) {
assert(!I->hasDLLImportStorageClass()
&& "Found dllimported non-external symbol!");
DefinedSymbols.insert(I->getName());
}
}
for (Module::alias_iterator I = M->alias_begin(), E = M->alias_end();
I != E; ++I)
if (I->hasName())
DefinedSymbols.insert(I->getName());
for (std::set<std::string>::iterator I = UndefinedSymbols.begin();
I != UndefinedSymbols.end(); )
if (DefinedSymbols.count(*I))
UndefinedSymbols.erase(I++);
else
++I;
}
/**
* Print the field declarations.
*/
void JVMWriter::printFields() {
out << "; Fields\n";
for(Module::global_iterator i = module->global_begin(),
e = module->global_end(); i != e; i++) {
if(i->isDeclaration()) {
out << ".extern field ";
externRefs.insert(i);
} else
out << ".field "
<< (i->hasLocalLinkage() ? "private " : "public ")
<< "static final ";
out << getValueName(i) << ' ' << getTypeDescriptor(i->getType());
if(debug >= 3)
out << " ; " << *i;
else
out << '\n';
}
out << '\n';
}
static void getSymbols(Module*M, std::vector<std::string>& symbols) {
// Loop over global variables
for (Module::global_iterator GI = M->global_begin(), GE=M->global_end(); GI != GE; ++GI)
if (!GI->isDeclaration() && !GI->hasLocalLinkage())
if (!GI->getName().empty())
symbols.push_back(GI->getName());
// Loop over functions
for (Module::iterator FI = M->begin(), FE = M->end(); FI != FE; ++FI)
if (!FI->isDeclaration() && !FI->hasLocalLinkage())
if (!FI->getName().empty())
symbols.push_back(FI->getName());
// Loop over aliases
for (Module::alias_iterator AI = M->alias_begin(), AE = M->alias_end();
AI != AE; ++AI) {
if (AI->hasName())
symbols.push_back(AI->getName());
}
}
bool ARMGlobalMerge::doInitialization(Module &M) {
SmallVector<GlobalVariable*, 16> Globals, ConstGlobals;
const TargetData *TD = TLI->getTargetData();
unsigned MaxOffset = TLI->getMaximalGlobalOffset();
bool Changed = false;
// Grab all non-const globals.
for (Module::global_iterator I = M.global_begin(),
E = M.global_end(); I != E; ++I) {
// Merge is safe for "normal" internal globals only
if (!I->hasLocalLinkage() || I->isThreadLocal() || I->hasSection())
continue;
// Ignore fancy-aligned globals for now.
if (I->getAlignment() != 0)
continue;
// Ignore all 'special' globals.
if (I->getName().startswith("llvm.") ||
I->getName().startswith(".llvm."))
continue;
if (TD->getTypeAllocSize(I->getType()) < MaxOffset) {
if (I->isConstant())
ConstGlobals.push_back(I);
else
Globals.push_back(I);
}
}
if (Globals.size() > 1)
Changed |= doMerge(Globals, M, false);
// FIXME: This currently breaks the EH processing due to way how the
// typeinfo detection works. We might want to detect the TIs and ignore
// them in the future.
// if (ConstGlobals.size() > 1)
// Changed |= doMerge(ConstGlobals, M, true);
return Changed;
}
static int runCompilePasses(Module *ModuleRef,
unsigned ModuleIndex,
ThreadedFunctionQueue *FuncQueue,
const Triple &TheTriple,
TargetMachine &Target,
StringRef ProgramName,
raw_pwrite_stream &OS){
PNaClABIErrorReporter ABIErrorReporter;
if (SplitModuleCount > 1 || ExternalizeAll) {
// Add function and global names, and give them external linkage.
// This relies on LLVM's consistent auto-generation of names, we could
// maybe do our own in case something changes there.
for (Function &F : *ModuleRef) {
if (!F.hasName())
F.setName("Function");
if (F.hasInternalLinkage())
F.setLinkage(GlobalValue::ExternalLinkage);
}
for (Module::global_iterator GI = ModuleRef->global_begin(),
GE = ModuleRef->global_end();
GI != GE; ++GI) {
if (!GI->hasName())
GI->setName("Global");
if (GI->hasInternalLinkage())
GI->setLinkage(GlobalValue::ExternalLinkage);
}
if (ModuleIndex > 0) {
// Remove the initializers for all global variables, turning them into
// declarations.
for (Module::global_iterator GI = ModuleRef->global_begin(),
GE = ModuleRef->global_end();
GI != GE; ++GI) {
assert(GI->hasInitializer() && "Global variable missing initializer");
Constant *Init = GI->getInitializer();
GI->setInitializer(nullptr);
if (Init->getNumUses() == 0)
Init->destroyConstant();
}
}
}
// Make all non-weak symbols hidden for better code. We cannot do
// this for weak symbols. The linker complains when some weak
// symbols are not resolved.
for (Function &F : *ModuleRef) {
if (!F.isWeakForLinker() && !F.hasLocalLinkage())
F.setVisibility(GlobalValue::HiddenVisibility);
}
for (Module::global_iterator GI = ModuleRef->global_begin(),
GE = ModuleRef->global_end();
GI != GE; ++GI) {
if (!GI->isWeakForLinker() && !GI->hasLocalLinkage())
GI->setVisibility(GlobalValue::HiddenVisibility);
}
// Build up all of the passes that we want to do to the module.
std::unique_ptr<legacy::PassManagerBase> PM;
if (LazyBitcode)
PM.reset(new legacy::FunctionPassManager(ModuleRef));
else
PM.reset(new legacy::PassManager());
// Add the target data from the target machine, if it exists, or the module.
if (const DataLayout *DL = Target.getDataLayout())
ModuleRef->setDataLayout(*DL);
// For conformance with llc, we let the user disable LLVM IR verification with
// -disable-verify. Unlike llc, when LLVM IR verification is enabled we only
// run it once, before PNaCl ABI verification.
if (!NoVerify)
PM->add(createVerifierPass());
// Add the ABI verifier pass before the analysis and code emission passes.
if (PNaClABIVerify)
PM->add(createPNaClABIVerifyFunctionsPass(&ABIErrorReporter));
// Add the intrinsic resolution pass. It assumes ABI-conformant code.
PM->add(createResolvePNaClIntrinsicsPass());
// Add an appropriate TargetLibraryInfo pass for the module's triple.
TargetLibraryInfoImpl TLII(TheTriple);
// The -disable-simplify-libcalls flag actually disables all builtin optzns.
if (DisableSimplifyLibCalls)
TLII.disableAllFunctions();
PM->add(new TargetLibraryInfoWrapperPass(TLII));
// Allow subsequent passes and the backend to better optimize instructions
// that were simplified for PNaCl's ABI. This pass uses the TargetLibraryInfo
// above.
PM->add(createBackendCanonicalizePass());
// Ask the target to add backend passes as necessary. We explicitly ask it
// not to add the verifier pass because we added it earlier.
if (Target.addPassesToEmitFile(*PM, OS, FileType,
/* DisableVerify */ true)) {
errs() << ProgramName
<< ": target does not support generation of this file type!\n";
return 1;
}
if (LazyBitcode) {
auto FPM = static_cast<legacy::FunctionPassManager *>(PM.get());
FPM->doInitialization();
unsigned FuncIndex = 0;
switch (SplitModuleSched) {
case SplitModuleStatic:
for (Function &F : *ModuleRef) {
if (FuncQueue->GrabFunctionStatic(FuncIndex, ModuleIndex)) {
FPM->run(F);
CheckABIVerifyErrors(ABIErrorReporter, "Function " + F.getName());
F.Dematerialize();
}
++FuncIndex;
}
break;
case SplitModuleDynamic:
unsigned ChunkSize = 0;
unsigned NumFunctions = FuncQueue->Size();
Module::iterator I = ModuleRef->begin();
while (FuncIndex < NumFunctions) {
ChunkSize = FuncQueue->RecommendedChunkSize();
unsigned NextIndex;
bool grabbed = FuncQueue->GrabFunctionDynamic(FuncIndex, ChunkSize,
NextIndex);
if (grabbed) {
while (FuncIndex < NextIndex) {
if (!I->isMaterializable() && I->isDeclaration()) {
++I;
continue;
}
FPM->run(*I);
CheckABIVerifyErrors(ABIErrorReporter, "Function " + I->getName());
I->Dematerialize();
++FuncIndex;
++I;
}
} else {
while (FuncIndex < NextIndex) {
if (!I->isMaterializable() && I->isDeclaration()) {
++I;
continue;
}
++FuncIndex;
++I;
}
}
}
break;
}
FPM->doFinalization();
} else
static_cast<legacy::PassManager *>(PM.get())->run(*ModuleRef);
return 0;
}
bool InternalizePass::runOnModule(Module &M) {
CallGraph *CG = getAnalysisIfAvailable<CallGraph>();
CallGraphNode *ExternalNode = CG ? CG->getExternalCallingNode() : 0;
if (ExternalNames.empty()) {
// Return if we're not in 'all but main' mode and have no external api
if (!AllButMain)
return false;
// If no list or file of symbols was specified, check to see if there is a
// "main" symbol defined in the module. If so, use it, otherwise do not
// internalize the module, it must be a library or something.
//
Function *MainFunc = M.getFunction("main");
if (MainFunc == 0 || MainFunc->isDeclaration())
return false; // No main found, must be a library...
// Preserve main, internalize all else.
ExternalNames.insert(MainFunc->getName());
}
bool Changed = false;
// Never internalize functions which code-gen might insert.
ExternalNames.insert("__stack_chk_fail");
// Mark all functions not in the api as internal.
// FIXME: maybe use private linkage?
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (!I->isDeclaration() && // Function must be defined here
// Available externally is really just a "declaration with a body".
!I->hasAvailableExternallyLinkage() &&
!I->hasLocalLinkage() && // Can't already have internal linkage
!ExternalNames.count(I->getName())) {// Not marked to keep external?
I->setLinkage(GlobalValue::InternalLinkage);
// Remove a callgraph edge from the external node to this function.
if (ExternalNode) ExternalNode->removeOneAbstractEdgeTo((*CG)[I]);
Changed = true;
++NumFunctions;
DEBUG(dbgs() << "Internalizing func " << I->getName() << "\n");
}
// Never internalize the llvm.used symbol. It is used to implement
// attribute((used)).
// FIXME: Shouldn't this just filter on llvm.metadata section??
ExternalNames.insert("llvm.used");
ExternalNames.insert("llvm.compiler.used");
// Never internalize anchors used by the machine module info, else the info
// won't find them. (see MachineModuleInfo.)
ExternalNames.insert("llvm.global_ctors");
ExternalNames.insert("llvm.global_dtors");
ExternalNames.insert("llvm.global.annotations");
// Never internalize symbols code-gen inserts.
ExternalNames.insert("__stack_chk_guard");
// Mark all global variables with initializers that are not in the api as
// internal as well.
// FIXME: maybe use private linkage?
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I)
if (!I->isDeclaration() && !I->hasLocalLinkage() &&
// Available externally is really just a "declaration with a body".
!I->hasAvailableExternallyLinkage() &&
!ExternalNames.count(I->getName())) {
I->setLinkage(GlobalValue::InternalLinkage);
Changed = true;
++NumGlobals;
DEBUG(dbgs() << "Internalized gvar " << I->getName() << "\n");
}
// Mark all aliases that are not in the api as internal as well.
for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end();
I != E; ++I)
if (!I->isDeclaration() && !I->hasInternalLinkage() &&
// Available externally is really just a "declaration with a body".
!I->hasAvailableExternallyLinkage() &&
!ExternalNames.count(I->getName())) {
I->setLinkage(GlobalValue::InternalLinkage);
Changed = true;
++NumAliases;
DEBUG(dbgs() << "Internalized alias " << I->getName() << "\n");
}
return Changed;
}
bool GlobalMerge::doInitialization(Module &M) {
if (!EnableGlobalMerge)
return false;
DenseMap<unsigned, SmallVector<GlobalVariable*, 16> > Globals, ConstGlobals,
BSSGlobals;
const TargetLowering *TLI = TM->getTargetLowering();
const DataLayout *DL = TLI->getDataLayout();
unsigned MaxOffset = TLI->getMaximalGlobalOffset();
bool Changed = false;
setMustKeepGlobalVariables(M);
// Grab all non-const globals.
for (Module::global_iterator I = M.global_begin(),
E = M.global_end(); I != E; ++I) {
// Merge is safe for "normal" internal globals only
if (!I->hasLocalLinkage() || I->isThreadLocal() || I->hasSection())
continue;
PointerType *PT = dyn_cast<PointerType>(I->getType());
assert(PT && "Global variable is not a pointer!");
unsigned AddressSpace = PT->getAddressSpace();
// Ignore fancy-aligned globals for now.
unsigned Alignment = DL->getPreferredAlignment(I);
Type *Ty = I->getType()->getElementType();
if (Alignment > DL->getABITypeAlignment(Ty))
continue;
// Ignore all 'special' globals.
if (I->getName().startswith("llvm.") ||
I->getName().startswith(".llvm."))
continue;
// Ignore all "required" globals:
if (isMustKeepGlobalVariable(I))
continue;
if (DL->getTypeAllocSize(Ty) < MaxOffset) {
if (TargetLoweringObjectFile::getKindForGlobal(I, TLI->getTargetMachine())
.isBSSLocal())
BSSGlobals[AddressSpace].push_back(I);
else if (I->isConstant())
ConstGlobals[AddressSpace].push_back(I);
else
Globals[AddressSpace].push_back(I);
}
}
for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
I = Globals.begin(), E = Globals.end(); I != E; ++I)
if (I->second.size() > 1)
Changed |= doMerge(I->second, M, false, I->first);
for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
I = BSSGlobals.begin(), E = BSSGlobals.end(); I != E; ++I)
if (I->second.size() > 1)
Changed |= doMerge(I->second, M, false, I->first);
if (EnableGlobalMergeOnConst)
for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
I = ConstGlobals.begin(), E = ConstGlobals.end(); I != E; ++I)
if (I->second.size() > 1)
Changed |= doMerge(I->second, M, true, I->first);
return Changed;
}
bool InternalizePass::runOnModule(Module &M) {
CallGraph *CG = getAnalysisIfAvailable<CallGraph>();
CallGraphNode *ExternalNode = CG ? CG->getExternalCallingNode() : 0;
bool Changed = false;
// Never internalize functions which code-gen might insert.
// FIXME: We should probably add this (and the __stack_chk_guard) via some
// type of call-back in CodeGen.
ExternalNames.insert("__stack_chk_fail");
// Mark all functions not in the api as internal.
// FIXME: maybe use private linkage?
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (!I->isDeclaration() && // Function must be defined here
// Available externally is really just a "declaration with a body".
!I->hasAvailableExternallyLinkage() &&
!I->hasLocalLinkage() && // Can't already have internal linkage
!ExternalNames.count(I->getName())) {// Not marked to keep external?
I->setLinkage(GlobalValue::InternalLinkage);
// Remove a callgraph edge from the external node to this function.
if (ExternalNode) ExternalNode->removeOneAbstractEdgeTo((*CG)[I]);
Changed = true;
++NumFunctions;
DEBUG(dbgs() << "Internalizing func " << I->getName() << "\n");
}
// Never internalize the llvm.used symbol. It is used to implement
// attribute((used)).
// FIXME: Shouldn't this just filter on llvm.metadata section??
ExternalNames.insert("llvm.used");
ExternalNames.insert("llvm.compiler.used");
// Never internalize anchors used by the machine module info, else the info
// won't find them. (see MachineModuleInfo.)
ExternalNames.insert("llvm.global_ctors");
ExternalNames.insert("llvm.global_dtors");
ExternalNames.insert("llvm.global.annotations");
// Never internalize symbols code-gen inserts.
ExternalNames.insert("__stack_chk_guard");
// Mark all global variables with initializers that are not in the api as
// internal as well.
// FIXME: maybe use private linkage?
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I)
if (!I->isDeclaration() && !I->hasLocalLinkage() &&
// Available externally is really just a "declaration with a body".
!I->hasAvailableExternallyLinkage() &&
!ExternalNames.count(I->getName())) {
I->setLinkage(GlobalValue::InternalLinkage);
Changed = true;
++NumGlobals;
DEBUG(dbgs() << "Internalized gvar " << I->getName() << "\n");
}
// Mark all aliases that are not in the api as internal as well.
for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end();
I != E; ++I)
if (!I->isDeclaration() && !I->hasInternalLinkage() &&
// Available externally is really just a "declaration with a body".
!I->hasAvailableExternallyLinkage() &&
!ExternalNames.count(I->getName())) {
I->setLinkage(GlobalValue::InternalLinkage);
Changed = true;
++NumAliases;
DEBUG(dbgs() << "Internalized alias " << I->getName() << "\n");
}
return Changed;
}
/// Based on GetAllUndefinedSymbols() from LLVM3.2
///
/// GetAllUndefinedSymbols - calculates the set of undefined symbols that still
/// exist in an LLVM module. This is a bit tricky because there may be two
/// symbols with the same name but different LLVM types that will be resolved to
/// each other but aren't currently (thus we need to treat it as resolved).
///
/// Inputs:
/// M - The module in which to find undefined symbols.
///
/// Outputs:
/// UndefinedSymbols - A set of C++ strings containing the name of all
/// undefined symbols.
///
static void
GetAllUndefinedSymbols(Module *M, std::set<std::string> &UndefinedSymbols) {
static const std::string llvmIntrinsicPrefix="llvm.";
std::set<std::string> DefinedSymbols;
UndefinedSymbols.clear();
KLEE_DEBUG_WITH_TYPE("klee_linker",
dbgs() << "*** Computing undefined symbols ***\n");
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
if (I->hasName()) {
if (I->isDeclaration())
UndefinedSymbols.insert(I->getName());
else if (!I->hasLocalLinkage()) {
#if LLVM_VERSION_CODE < LLVM_VERSION(3, 5)
assert(!I->hasDLLImportLinkage() && "Found dllimported non-external symbol!");
#else
assert(!I->hasDLLImportStorageClass() && "Found dllimported non-external symbol!");
#endif
DefinedSymbols.insert(I->getName());
}
}
for (Module::global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I)
if (I->hasName()) {
if (I->isDeclaration())
UndefinedSymbols.insert(I->getName());
else if (!I->hasLocalLinkage()) {
#if LLVM_VERSION_CODE < LLVM_VERSION(3, 5)
assert(!I->hasDLLImportLinkage() && "Found dllimported non-external symbol!");
#else
assert(!I->hasDLLImportStorageClass() && "Found dllimported non-external symbol!");
#endif
DefinedSymbols.insert(I->getName());
}
}
for (Module::alias_iterator I = M->alias_begin(), E = M->alias_end();
I != E; ++I)
if (I->hasName())
DefinedSymbols.insert(I->getName());
// Prune out any defined symbols from the undefined symbols set
// and other symbols we don't want to treat as an undefined symbol
std::vector<std::string> SymbolsToRemove;
for (std::set<std::string>::iterator I = UndefinedSymbols.begin();
I != UndefinedSymbols.end(); ++I )
{
if (DefinedSymbols.count(*I))
{
SymbolsToRemove.push_back(*I);
continue;
}
// Strip out llvm intrinsics
if ( (I->size() >= llvmIntrinsicPrefix.size() ) &&
(I->compare(0, llvmIntrinsicPrefix.size(), llvmIntrinsicPrefix) == 0) )
{
KLEE_DEBUG_WITH_TYPE("klee_linker", dbgs() << "LLVM intrinsic " << *I <<
" has will be removed from undefined symbols"<< "\n");
SymbolsToRemove.push_back(*I);
continue;
}
// Symbol really is undefined
KLEE_DEBUG_WITH_TYPE("klee_linker",
dbgs() << "Symbol " << *I << " is undefined.\n");
}
// Remove KLEE intrinsics from set of undefined symbols
for (SpecialFunctionHandler::const_iterator sf = SpecialFunctionHandler::begin(),
se = SpecialFunctionHandler::end(); sf != se; ++sf)
{
if (UndefinedSymbols.find(sf->name) == UndefinedSymbols.end())
continue;
SymbolsToRemove.push_back(sf->name);
KLEE_DEBUG_WITH_TYPE("klee_linker",
dbgs() << "KLEE intrinsic " << sf->name <<
" has will be removed from undefined symbols"<< "\n");
}
// Now remove the symbols from undefined set.
for (size_t i = 0, j = SymbolsToRemove.size(); i < j; ++i )
UndefinedSymbols.erase(SymbolsToRemove[i]);
KLEE_DEBUG_WITH_TYPE("klee_linker",
dbgs() << "*** Finished computing undefined symbols ***\n");
}