[llvm-commits] [llvm] r110751 - /llvm/trunk/tools/lto/LTOModule.cpp
Daniel Dunbar
daniel at zuster.org
Tue Aug 10 16:46:40 PDT 2010
Author: ddunbar
Date: Tue Aug 10 18:46:39 2010
New Revision: 110751
URL: http://llvm.org/viewvc/llvm-project?rev=110751&view=rev
Log:
LTOModule.cpp: Fix numerous style issues.
Modified:
llvm/trunk/tools/lto/LTOModule.cpp
Modified: llvm/trunk/tools/lto/LTOModule.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/lto/LTOModule.cpp?rev=110751&r1=110750&r2=110751&view=diff
==============================================================================
--- llvm/trunk/tools/lto/LTOModule.cpp (original)
+++ llvm/trunk/tools/lto/LTOModule.cpp Tue Aug 10 18:46:39 2010
@@ -4,10 +4,10 @@
//
// 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
+// This file implements the Link Time Optimization library. This library is
// intended to be used by linker to optimize code at link time.
//
//===----------------------------------------------------------------------===//
@@ -36,495 +36,472 @@
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 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::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 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::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);
+// 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(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);
+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));
+/// 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(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();
+LTOModule *LTOModule::makeLTOModule(MemoryBuffer *buffer,
+ std::string &errMsg) {
+ InitializeAllTargets();
- // parse bitcode buffer
- OwningPtr<Module> m(ParseBitcodeFile(buffer, getGlobalContext(), &errMsg));
- if (!m)
- return NULL;
+ // 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();
+ 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;
+ // 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);
+ // 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();
+const char *LTOModule::getTargetTriple() {
+ return _module->getTargetTriple().c_str();
}
-void LTOModule::setTargetTriple(const char *triple)
-{
- _module->setTargetTriple(triple);
+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);
+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);
- }
- }
+ // 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;
- }
- }
+// 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;
+ }
+ 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 = ::strdup(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 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 = ::strdup(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 = ::strdup(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)
-{
+// 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(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;
- // 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;
+ 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;
+ // string is owned by _undefines
+ _undefines[info.name] = info;
+ }
+ }
+ }
}
-void LTOModule::addAsmGlobalSymbol(const char *name) {
- // only add new define if not already defined
- if (_defines.count(name) == 0)
- 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;
+// Parse i386/ppc ObjC class list data structure.
+void LTOModule::addObjCClassRef(GlobalVariable *clgv) {
+ std::string targetclassName;
+ if (objcClassNameFromExpression(clgv->getInitializer(), targetclassName)) {
NameAndAttributes info;
- // string is owned by _undefines
- info.name = ::strdup(name.c_str());
- if (decl->hasExternalWeakLinkage())
- info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
- else
+ 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[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);
+ // string is owned by _undefines
+ _undefines[info.name] = info;
}
+ }
}
-void LTOModule::lazyParseSymbols()
-{
- if (!_symbolsParsed) {
- _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());
+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;
+ }
- // search next .globl
- pos = inlineAsm.find(glbl, pend);
- }
+ // 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;
- // 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);
- }
- }
- }
+ // add to table of symbols
+ NameAndAttributes info;
+ info.name = symbolName;
+ info.attributes = (lto_symbol_attributes)attr;
+ _symbols.push_back(info);
+ _defines[info.name] = 1;
}
-
-uint32_t LTOModule::getSymbolCount()
-{
- lazyParseSymbols();
- return _symbols.size();
+void LTOModule::addAsmGlobalSymbol(const char *name) {
+ // only add new define if not already defined
+ if (_defines.count(name) == 0)
+ 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;
}
-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;
+// 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) {
+ _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;
}
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