#include "LTOModule.h"
#include "llvm/Constants.h"
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/Support/SystemUtils.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/System/Host.h"
#include "llvm/System/Path.h"
#include "llvm/System/Process.h"
#include "llvm/Target/Mangler.h"
#include "llvm/Target/SubtargetFeature.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Target/TargetSelect.h"
using namespace llvm;
bool LTOModule::isBitcodeFile(const void* mem, size_t length)
{
return llvm::sys::IdentifyFileType((char*)mem, length)
== llvm::sys::Bitcode_FileType;
}
bool LTOModule::isBitcodeFile(const char* path)
{
return llvm::sys::Path(path).isBitcodeFile();
}
bool LTOModule::isBitcodeFileForTarget(const void* mem, size_t length,
const char* triplePrefix)
{
MemoryBuffer* buffer = makeBuffer(mem, length);
if (!buffer)
return false;
return isTargetMatch(buffer, triplePrefix);
}
bool LTOModule::isBitcodeFileForTarget(const char* path,
const char* triplePrefix)
{
MemoryBuffer *buffer = MemoryBuffer::getFile(path);
if (buffer == NULL)
return false;
return isTargetMatch(buffer, triplePrefix);
}
bool LTOModule::isTargetMatch(MemoryBuffer* buffer, const char* triplePrefix)
{
OwningPtr<Module> m(getLazyBitcodeModule(buffer, getGlobalContext()));
if (!m) {
delete buffer;
return false;
}
std::string actualTarget = m->getTargetTriple();
return (strncmp(actualTarget.c_str(), triplePrefix,
strlen(triplePrefix)) == 0);
}
LTOModule::LTOModule(Module* m, TargetMachine* t)
: _module(m), _target(t), _symbolsParsed(false)
{
}
LTOModule* LTOModule::makeLTOModule(const char* path,
std::string& errMsg)
{
OwningPtr<MemoryBuffer> buffer(MemoryBuffer::getFile(path, &errMsg));
if (!buffer)
return NULL;
return makeLTOModule(buffer.get(), errMsg);
}
MemoryBuffer* LTOModule::makeBuffer(const void* mem, size_t length)
{
const char *startPtr = (char*)mem;
const char *endPtr = startPtr+length;
if (((uintptr_t)endPtr & (sys::Process::GetPageSize()-1)) == 0 ||
*endPtr != 0)
return MemoryBuffer::getMemBufferCopy(StringRef(startPtr, length));
return MemoryBuffer::getMemBuffer(StringRef(startPtr, length));
}
LTOModule* LTOModule::makeLTOModule(const void* mem, size_t length,
std::string& errMsg)
{
OwningPtr<MemoryBuffer> buffer(makeBuffer(mem, length));
if (!buffer)
return NULL;
return makeLTOModule(buffer.get(), errMsg);
}
LTOModule* LTOModule::makeLTOModule(MemoryBuffer* buffer,
std::string& errMsg)
{
InitializeAllTargets();
OwningPtr<Module> m(ParseBitcodeFile(buffer, getGlobalContext(), &errMsg));
if (!m)
return NULL;
std::string Triple = m->getTargetTriple();
if (Triple.empty())
Triple = sys::getHostTriple();
const Target* march = TargetRegistry::lookupTarget(Triple, errMsg);
if (!march)
return NULL;
SubtargetFeatures Features;
Features.getDefaultSubtargetFeatures("" , llvm::Triple(Triple));
std::string FeatureStr = Features.getString();
TargetMachine* target = march->createTargetMachine(Triple, FeatureStr);
return new LTOModule(m.take(), target);
}
const char* LTOModule::getTargetTriple()
{
return _module->getTargetTriple().c_str();
}
void LTOModule::addDefinedFunctionSymbol(Function* f, Mangler &mangler)
{
addDefinedSymbol(f, mangler, true);
for (Function::iterator b = f->begin(); b != f->end(); ++b) {
for (BasicBlock::iterator i = b->begin(); i != b->end(); ++i) {
for (unsigned count = 0, total = i->getNumOperands();
count != total; ++count) {
findExternalRefs(i->getOperand(count), mangler);
}
}
}
}
bool LTOModule::objcClassNameFromExpression(Constant* c, std::string& name)
{
if (ConstantExpr* ce = dyn_cast<ConstantExpr>(c)) {
Constant* op = ce->getOperand(0);
if (GlobalVariable* gvn = dyn_cast<GlobalVariable>(op)) {
Constant* cn = gvn->getInitializer();
if (ConstantArray* ca = dyn_cast<ConstantArray>(cn)) {
if (ca->isCString()) {
name = ".objc_class_name_" + ca->getAsString();
return true;
}
}
}
}
return false;
}
void LTOModule::addObjCClass(GlobalVariable* clgv)
{
if (ConstantStruct* c = dyn_cast<ConstantStruct>(clgv->getInitializer())) {
std::string superclassName;
if (objcClassNameFromExpression(c->getOperand(1), superclassName)) {
NameAndAttributes info;
if (_undefines.find(superclassName.c_str()) == _undefines.end()) {
const char* symbolName = ::strdup(superclassName.c_str());
info.name = ::strdup(symbolName);
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
_undefines[info.name] = info;
}
}
std::string className;
if (objcClassNameFromExpression(c->getOperand(2), className)) {
const char* symbolName = ::strdup(className.c_str());
NameAndAttributes info;
info.name = symbolName;
info.attributes = (lto_symbol_attributes)
(LTO_SYMBOL_PERMISSIONS_DATA |
LTO_SYMBOL_DEFINITION_REGULAR |
LTO_SYMBOL_SCOPE_DEFAULT);
_symbols.push_back(info);
_defines[info.name] = 1;
}
}
}
void LTOModule::addObjCCategory(GlobalVariable* clgv)
{
if (ConstantStruct* c = dyn_cast<ConstantStruct>(clgv->getInitializer())) {
std::string targetclassName;
if (objcClassNameFromExpression(c->getOperand(1), targetclassName)) {
NameAndAttributes info;
if (_undefines.find(targetclassName.c_str()) == _undefines.end()) {
const char* symbolName = ::strdup(targetclassName.c_str());
info.name = ::strdup(symbolName);
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
_undefines[info.name] = info;
}
}
}
}
void LTOModule::addObjCClassRef(GlobalVariable* clgv)
{
std::string targetclassName;
if (objcClassNameFromExpression(clgv->getInitializer(), targetclassName)) {
NameAndAttributes info;
if (_undefines.find(targetclassName.c_str()) == _undefines.end()) {
const char* symbolName = ::strdup(targetclassName.c_str());
info.name = ::strdup(symbolName);
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
_undefines[info.name] = info;
}
}
}
void LTOModule::addDefinedDataSymbol(GlobalValue* v, Mangler& mangler)
{
addDefinedSymbol(v, mangler, false);
if (v->hasSection() ) {
if (v->getSection().compare(0, 15, "__OBJC,__class,") == 0) {
if (GlobalVariable* gv = dyn_cast<GlobalVariable>(v)) {
addObjCClass(gv);
}
}
else if (v->getSection().compare(0, 18, "__OBJC,__category,") == 0) {
if (GlobalVariable* gv = dyn_cast<GlobalVariable>(v)) {
addObjCCategory(gv);
}
}
else if (v->getSection().compare(0, 18, "__OBJC,__cls_refs,") == 0) {
if (GlobalVariable* gv = dyn_cast<GlobalVariable>(v)) {
addObjCClassRef(gv);
}
}
}
for (unsigned count = 0, total = v->getNumOperands();
count != total; ++count) {
findExternalRefs(v->getOperand(count), mangler);
}
}
void LTOModule::addDefinedSymbol(GlobalValue* def, Mangler &mangler,
bool isFunction)
{
if (def->getName().startswith("llvm."))
return;
const char* symbolName = ::strdup(mangler.getNameWithPrefix(def).c_str());
uint32_t align = def->getAlignment();
uint32_t attr = align ? CountTrailingZeros_32(def->getAlignment()) : 0;
if (isFunction)
attr |= LTO_SYMBOL_PERMISSIONS_CODE;
else {
GlobalVariable* gv = dyn_cast<GlobalVariable>(def);
if (gv && gv->isConstant())
attr |= LTO_SYMBOL_PERMISSIONS_RODATA;
else
attr |= LTO_SYMBOL_PERMISSIONS_DATA;
}
if (def->hasWeakLinkage() || def->hasLinkOnceLinkage()) {
attr |= LTO_SYMBOL_DEFINITION_WEAK;
}
else if (def->hasCommonLinkage()) {
attr |= LTO_SYMBOL_DEFINITION_TENTATIVE;
}
else {
attr |= LTO_SYMBOL_DEFINITION_REGULAR;
}
if (def->hasHiddenVisibility())
attr |= LTO_SYMBOL_SCOPE_HIDDEN;
else if (def->hasProtectedVisibility())
attr |= LTO_SYMBOL_SCOPE_PROTECTED;
else if (def->hasExternalLinkage() || def->hasWeakLinkage()
|| def->hasLinkOnceLinkage() || def->hasCommonLinkage())
attr |= LTO_SYMBOL_SCOPE_DEFAULT;
else
attr |= LTO_SYMBOL_SCOPE_INTERNAL;
NameAndAttributes info;
info.name = symbolName;
info.attributes = (lto_symbol_attributes)attr;
_symbols.push_back(info);
_defines[info.name] = 1;
}
void LTOModule::addAsmGlobalSymbol(const char *name) {
if (_defines.count(name))
return;
const char *symbolName = ::strdup(name);
uint32_t attr = LTO_SYMBOL_DEFINITION_REGULAR;
attr |= LTO_SYMBOL_SCOPE_DEFAULT;
NameAndAttributes info;
info.name = symbolName;
info.attributes = (lto_symbol_attributes)attr;
_symbols.push_back(info);
_defines[info.name] = 1;
}
void LTOModule::addPotentialUndefinedSymbol(GlobalValue* decl, Mangler &mangler)
{
if (decl->getName().startswith("llvm."))
return;
if (isa<GlobalAlias>(decl))
return;
std::string name = mangler.getNameWithPrefix(decl);
if (_undefines.find(name) != _undefines.end())
return;
NameAndAttributes info;
info.name = ::strdup(name.c_str());
if (decl->hasExternalWeakLinkage())
info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
else
info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;
_undefines[name] = info;
}
void LTOModule::findExternalRefs(Value* value, Mangler &mangler) {
if (GlobalValue* gv = dyn_cast<GlobalValue>(value)) {
if (!gv->hasExternalLinkage())
addPotentialUndefinedSymbol(gv, mangler);
return;
}
if (Constant* c = dyn_cast<Constant>(value)) {
for (unsigned i = 0, e = c->getNumOperands(); i != e; ++i)
findExternalRefs(c->getOperand(i), mangler);
}
}
void LTOModule::lazyParseSymbols()
{
if (!_symbolsParsed) {
_symbolsParsed = true;
MCContext Context(*_target->getMCAsmInfo());
Mangler mangler(Context, *_target->getTargetData());
for (Module::iterator f = _module->begin(); f != _module->end(); ++f) {
if (f->isDeclaration())
addPotentialUndefinedSymbol(f, mangler);
else
addDefinedFunctionSymbol(f, mangler);
}
for (Module::global_iterator v = _module->global_begin(),
e = _module->global_end(); v != e; ++v) {
if (v->isDeclaration())
addPotentialUndefinedSymbol(v, mangler);
else
addDefinedDataSymbol(v, mangler);
}
const std::string &inlineAsm = _module->getModuleInlineAsm();
const std::string glbl = ".globl";
std::string asmSymbolName;
std::string::size_type pos = inlineAsm.find(glbl, 0);
while (pos != std::string::npos) {
pos = pos + 6;
std::string::size_type pbegin = inlineAsm.find_first_not_of(' ', pos);
if (pbegin == std::string::npos)
break;
std::string::size_type pend = inlineAsm.find_first_of('\n', pbegin);
if (pend == std::string::npos)
break;
asmSymbolName.assign(inlineAsm, pbegin, pend - pbegin);
addAsmGlobalSymbol(asmSymbolName.c_str());
pos = inlineAsm.find(glbl, pend);
}
for (StringMap<NameAndAttributes>::iterator it=_undefines.begin();
it != _undefines.end(); ++it) {
if (_defines.count(it->getKey()) == 0) {
NameAndAttributes info = it->getValue();
_symbols.push_back(info);
}
}
}
}
uint32_t LTOModule::getSymbolCount()
{
lazyParseSymbols();
return _symbols.size();
}
lto_symbol_attributes LTOModule::getSymbolAttributes(uint32_t index)
{
lazyParseSymbols();
if (index < _symbols.size())
return _symbols[index].attributes;
else
return lto_symbol_attributes(0);
}
const char* LTOModule::getSymbolName(uint32_t index)
{
lazyParseSymbols();
if (index < _symbols.size())
return _symbols[index].name;
else
return NULL;
}