X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=tools%2Flto%2FLTOModule.cpp;h=939d0eacd1e30736a652df535c057fdcdffd94a5;hb=4bdf73025a56bd2affad27f6eae93c7f8d2a06d4;hp=7eb79053ea9786e46bc79c70bebb9be8a07925c5;hpb=db6535dd2008897f6446dcfa1ae754d1a6eb0270;p=oota-llvm.git diff --git a/tools/lto/LTOModule.cpp b/tools/lto/LTOModule.cpp index 7eb79053ea9..939d0eacd1e 100644 --- a/tools/lto/LTOModule.cpp +++ b/tools/lto/LTOModule.cpp @@ -14,6 +14,7 @@ #include "LTOModule.h" +#include "llvm/Constants.h" #include "llvm/Module.h" #include "llvm/ModuleProvider.h" #include "llvm/ADT/OwningPtr.h" @@ -108,7 +109,7 @@ MemoryBuffer* LTOModule::makeBuffer(const void* mem, size_t length) LTOModule* LTOModule::makeLTOModule(const void* mem, size_t length, - std::string& errMsg) + std::string& errMsg) { OwningPtr buffer(makeBuffer(mem, length)); if ( !buffer ) @@ -176,11 +177,141 @@ void LTOModule::addDefinedFunctionSymbol(Function* f, Mangler &mangler) } } -void LTOModule::addDefinedDataSymbol(GlobalValue* v, Mangler &mangler) +// get string that data pointer points to +bool LTOModule::objcClassNameFromExpression(Constant* c, std::string& name) +{ + if (ConstantExpr* ce = dyn_cast(c)) { + Constant* op = ce->getOperand(0); + if (GlobalVariable* gvn = dyn_cast(op)) { + Constant* cn = gvn->getInitializer(); + if (ConstantArray* ca = dyn_cast(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(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(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) +{ + 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(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(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(v)) { + addObjCClassRef(gv); + } + } + } + // add external symbols referenced by this data. for (unsigned count = 0, total = v->getNumOperands(); count != total; ++count) { @@ -192,9 +323,13 @@ void LTOModule::addDefinedDataSymbol(GlobalValue* v, Mangler &mangler) void LTOModule::addDefinedSymbol(GlobalValue* def, Mangler &mangler, bool isFunction) { + // ignore all llvm.* symbols + if ( strncmp(def->getNameStart(), "llvm.", 5) == 0 ) + return; + // string is owned by _defines const char* symbolName = ::strdup(mangler.getValueName(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; @@ -224,6 +359,8 @@ void LTOModule::addDefinedSymbol(GlobalValue* def, Mangler &mangler, // 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; @@ -239,26 +376,41 @@ void LTOModule::addDefinedSymbol(GlobalValue* def, Mangler &mangler, } void LTOModule::addAsmGlobalSymbol(const char *name) { - // string is owned by _defines - const char *symbolName = ::strdup(name); - uint32_t attr = LTO_SYMBOL_DEFINITION_REGULAR; - attr |= LTO_SYMBOL_SCOPE_DEFAULT; - - // add to table of symbols - NameAndAttributes info; - info.name = symbolName; - info.attributes = (lto_symbol_attributes)attr; - _symbols.push_back(info); - _defines[info.name] = 1; + // only add new define if not already defined + if ( _defines.count(name, &name[strlen(name)+1]) == 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) { - const char* name = mangler.getValueName(decl).c_str(); // ignore all llvm.* symbols - if ( strncmp(name, "llvm.", 5) != 0 ) { - _undefines[name] = 1; - } + if ( strncmp(decl->getNameStart(), "llvm.", 5) == 0 ) + return; + + const char* name = mangler.getValueName(decl).c_str(); + + // we already have the symbol + if (_undefines.find(name) != _undefines.end()) + return; + + NameAndAttributes info; + // string is owned by _undefines + info.name = ::strdup(name); + if (decl->hasExternalWeakLinkage()) + info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF; + else + info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED; + _undefines[name] = info; } @@ -292,6 +444,14 @@ void LTOModule::lazyParseSymbols() // Use mangler to add GlobalPrefix to names to match linker names. Mangler mangler(*_module, _target->getTargetAsmInfo()->getGlobalPrefix()); + // add chars used in ObjC method names so method names aren't mangled + mangler.markCharAcceptable('['); + mangler.markCharAcceptable(']'); + mangler.markCharAcceptable('('); + mangler.markCharAcceptable(')'); + mangler.markCharAcceptable('-'); + mangler.markCharAcceptable('+'); + mangler.markCharAcceptable(' '); // add functions for (Module::iterator f = _module->begin(); f != _module->end(); ++f) { @@ -337,16 +497,14 @@ void LTOModule::lazyParseSymbols() } // make symbols for all undefines - for (StringSet::iterator it=_undefines.begin(); + for (StringMap::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->getKeyData(), it->getKeyData()+ it->getKeyLength()) == 0 ) { - NameAndAttributes info; - info.name = it->getKeyData(); - info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED; - _symbols.push_back(info); + NameAndAttributes info = it->getValue(); + _symbols.push_back(info); } } }