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Diffstat (limited to 'contrib/llvm/tools/lto/LTOModule.cpp')
| -rw-r--r-- | contrib/llvm/tools/lto/LTOModule.cpp | 508 |
1 files changed, 0 insertions, 508 deletions
diff --git a/contrib/llvm/tools/lto/LTOModule.cpp b/contrib/llvm/tools/lto/LTOModule.cpp deleted file mode 100644 index c7cd585..0000000 --- a/contrib/llvm/tools/lto/LTOModule.cpp +++ /dev/null @@ -1,508 +0,0 @@ -//===-- LTOModule.cpp - LLVM Link Time Optimizer --------------------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements the Link Time Optimization library. This library is -// intended to be used by linker to optimize code at link time. -// -//===----------------------------------------------------------------------===// - -#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); -} - -// Takes ownership of buffer. -bool LTOModule::isTargetMatch(MemoryBuffer *buffer, const char *triplePrefix) { - OwningPtr<Module> m(getLazyBitcodeModule(buffer, getGlobalContext())); - // On success, m owns buffer and both are deleted at end of this method. - 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); -} - -/// makeBuffer - Create a MemoryBuffer from a memory range. MemoryBuffer -/// requires the byte past end of the buffer to be a zero. We might get lucky -/// and already be that way, otherwise make a copy. Also if next byte is on a -/// different page, don't assume it is readable. -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(); - - // parse bitcode buffer - OwningPtr<Module> m(ParseBitcodeFile(buffer, getGlobalContext(), &errMsg)); - if (!m) - return NULL; - - std::string Triple = m->getTargetTriple(); - if (Triple.empty()) - Triple = sys::getHostTriple(); - - // find machine architecture for this module - const Target *march = TargetRegistry::lookupTarget(Triple, errMsg); - if (!march) - return NULL; - - // construct LTModule, hand over ownership of module and target - SubtargetFeatures Features; - Features.getDefaultSubtargetFeatures("" /* cpu */, 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::setTargetTriple(const char *triple) { - _module->setTargetTriple(triple); -} - -void LTOModule::addDefinedFunctionSymbol(Function *f, Mangler &mangler) { - // add to list of defined symbols - addDefinedSymbol(f, mangler, true); - - // add external symbols referenced by this function. - 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); - } - } - } -} - -// Get string that data pointer points to. -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; -} - -// Parse i386/ppc ObjC class data structure. -void LTOModule::addObjCClass(GlobalVariable *clgv) { - if (ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer())) { - // second slot in __OBJC,__class is pointer to superclass name - 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 = symbolName; - info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED; - // string is owned by _undefines - _undefines[info.name] = info; - } - } - // third slot in __OBJC,__class is pointer to class name - 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; - } - } -} - - -// Parse i386/ppc ObjC category data structure. -void LTOModule::addObjCCategory(GlobalVariable *clgv) { - if (ConstantStruct *c = dyn_cast<ConstantStruct>(clgv->getInitializer())) { - // second slot in __OBJC,__category is pointer to target class name - 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 = symbolName; - info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED; - // string is owned by _undefines - _undefines[info.name] = info; - } - } - } -} - - -// Parse i386/ppc ObjC class list data structure. -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 = symbolName; - info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED; - // string is owned by _undefines - _undefines[info.name] = info; - } - } -} - - -void LTOModule::addDefinedDataSymbol(GlobalValue *v, Mangler &mangler) { - // Add to list of defined symbols. - addDefinedSymbol(v, mangler, false); - - // Special case i386/ppc ObjC data structures in magic sections: - // The issue is that the old ObjC object format did some strange - // contortions to avoid real linker symbols. For instance, the - // ObjC class data structure is allocated statically in the executable - // that defines that class. That data structures contains a pointer to - // its superclass. But instead of just initializing that part of the - // struct to the address of its superclass, and letting the static and - // dynamic linkers do the rest, the runtime works by having that field - // instead point to a C-string that is the name of the superclass. - // At runtime the objc initialization updates that pointer and sets - // it to point to the actual super class. As far as the linker - // knows it is just a pointer to a string. But then someone wanted the - // linker to issue errors at build time if the superclass was not found. - // So they figured out a way in mach-o object format to use an absolute - // symbols (.objc_class_name_Foo = 0) and a floating reference - // (.reference .objc_class_name_Bar) to cause the linker into erroring when - // a class was missing. - // The following synthesizes the implicit .objc_* symbols for the linker - // from the ObjC data structures generated by the front end. - if (v->hasSection() /* && isTargetDarwin */) { - // special case if this data blob is an ObjC class definition - if (v->getSection().compare(0, 15, "__OBJC,__class,") == 0) { - if (GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) { - addObjCClass(gv); - } - } - - // special case if this data blob is an ObjC category definition - else if (v->getSection().compare(0, 18, "__OBJC,__category,") == 0) { - if (GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) { - addObjCCategory(gv); - } - } - - // special case if this data blob is the list of referenced classes - else if (v->getSection().compare(0, 18, "__OBJC,__cls_refs,") == 0) { - if (GlobalVariable *gv = dyn_cast<GlobalVariable>(v)) { - addObjCClassRef(gv); - } - } - } - - // add external symbols referenced by this data. - for (unsigned count = 0, total = v->getNumOperands(); - count != total; ++count) { - findExternalRefs(v->getOperand(count), mangler); - } -} - - -void LTOModule::addDefinedSymbol(GlobalValue *def, Mangler &mangler, - bool isFunction) { - // ignore all llvm.* symbols - if (def->getName().startswith("llvm.")) - return; - - // string is owned by _defines - const char *symbolName = ::strdup(mangler.getNameWithPrefix(def).c_str()); - - // set alignment part log2() can have rounding errors - uint32_t align = def->getAlignment(); - uint32_t attr = align ? CountTrailingZeros_32(def->getAlignment()) : 0; - - // set permissions part - 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; - } - - // set definition part - 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; - } - - // set scope part - 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; - - // add to table of symbols - 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) { - // only add new define if not already defined - if (_defines.count(name)) - return; - - // string is owned by _defines - 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) { - // ignore all llvm.* symbols - if (decl->getName().startswith("llvm.")) - return; - - // ignore all aliases - if (isa<GlobalAlias>(decl)) - return; - - std::string name = mangler.getNameWithPrefix(decl); - - // we already have the symbol - if (_undefines.find(name) != _undefines.end()) - return; - - NameAndAttributes info; - // string is owned by _undefines - 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; -} - - - -// Find external symbols referenced by VALUE. This is a recursive function. -void LTOModule::findExternalRefs(Value *value, Mangler &mangler) { - if (GlobalValue *gv = dyn_cast<GlobalValue>(value)) { - if (!gv->hasExternalLinkage()) - addPotentialUndefinedSymbol(gv, mangler); - // If this is a variable definition, do not recursively process - // initializer. It might contain a reference to this variable - // and cause an infinite loop. The initializer will be - // processed in addDefinedDataSymbol(). - return; - } - - // GlobalValue, even with InternalLinkage type, may have operands with - // ExternalLinkage type. Do not ignore these operands. - if (Constant *c = dyn_cast<Constant>(value)) { - // Handle ConstantExpr, ConstantStruct, ConstantArry etc. - for (unsigned i = 0, e = c->getNumOperands(); i != e; ++i) - findExternalRefs(c->getOperand(i), mangler); - } -} - -void LTOModule::lazyParseSymbols() { - if (_symbolsParsed) - return; - - _symbolsParsed = true; - - // Use mangler to add GlobalPrefix to names to match linker names. - MCContext Context(*_target->getMCAsmInfo()); - Mangler mangler(Context, *_target->getTargetData()); - - // add functions - for (Module::iterator f = _module->begin(); f != _module->end(); ++f) { - if (f->isDeclaration()) - addPotentialUndefinedSymbol(f, mangler); - else - addDefinedFunctionSymbol(f, mangler); - } - - // add data - 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); - } - - // add asm globals - 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) { - // eat .globl - pos = pos + 6; - - // skip white space between .globl and symbol name - std::string::size_type pbegin = inlineAsm.find_first_not_of(' ', pos); - if (pbegin == std::string::npos) - break; - - // find end-of-line - 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()); - - // search next .globl - pos = inlineAsm.find(glbl, pend); - } - - // make symbols for all undefines - for (StringMap<NameAndAttributes>::iterator it=_undefines.begin(); - it != _undefines.end(); ++it) { - // if this symbol also has a definition, then don't make an undefine - // because it is a tentative definition - 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; -} |
