X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FLinker%2FLinkArchives.cpp;h=99f3a1b60d28497fcb3d6a7d3a50d85da48789f5;hb=12945acd4aa40b40b1517bcf785622ab9671893f;hp=75e3df3f7f597b026ef30616e908924a91a05d54;hpb=3b3640a3733c6ecdba4a8ca2ca9d28a6ce957769;p=oota-llvm.git diff --git a/lib/Linker/LinkArchives.cpp b/lib/Linker/LinkArchives.cpp index 75e3df3f7f5..99f3a1b60d2 100644 --- a/lib/Linker/LinkArchives.cpp +++ b/lib/Linker/LinkArchives.cpp @@ -1,4 +1,4 @@ -//===- Linker.cpp - Link together LLVM objects and libraries --------------===// +//===- lib/Linker/LinkArchives.cpp - Link LLVM objects and libraries ------===// // // The LLVM Compiler Infrastructure // @@ -12,98 +12,24 @@ // //===----------------------------------------------------------------------===// -#include "gccld.h" +#include "llvm/Linker.h" #include "llvm/Module.h" -#include "llvm/PassManager.h" +#include "llvm/ModuleProvider.h" +#include "llvm/ADT/SetOperations.h" #include "llvm/Bytecode/Reader.h" -#include "llvm/Bytecode/WriteBytecodePass.h" -#include "llvm/Target/TargetData.h" -#include "llvm/Transforms/IPO.h" -#include "llvm/Transforms/Scalar.h" -#include "llvm/Transforms/Utils/Linker.h" -#include "Support/CommandLine.h" -#include "Support/FileUtilities.h" -#include "Support/Signals.h" -#include "Support/SystemUtils.h" -#include -#include +#include "llvm/Bytecode/Archive.h" +#include "llvm/Config/config.h" #include #include +#include -/// FileExists - Returns true IFF a file named FN exists and is readable. -/// -static inline bool FileExists(const std::string &FN) { - return access(FN.c_str(), R_OK | F_OK) != -1; -} - -/// IsArchive - Returns true IFF the file named FN appears to be a "ar" library -/// archive. The file named FN must exist. -/// -static inline bool IsArchive(const std::string &FN) { - // Inspect the beginning of the file to see if it contains the "ar" magic - // string. - std::string ArchiveMagic("!\012"); - char buf[1 + ArchiveMagic.size()]; - std::ifstream f(FN.c_str()); - f.read(buf, ArchiveMagic.size()); - buf[ArchiveMagic.size()] = '\0'; - return ArchiveMagic == buf; -} - -/// FindLib - locates a particular library. It will prepend and append -/// various directories, prefixes, and suffixes until it can find the library. -/// -/// Inputs: -/// Filename - Name of the file to find. -/// Paths - List of directories to search. -/// -/// Outputs: -/// None. -/// -/// Return value: -/// The name of the file is returned. -/// If the file is not found, an empty string is returned. -/// -static std::string -FindLib(const std::string &Filename, const std::vector &Paths) { - // Determine if the pathname can be found as it stands. - if (FileExists(Filename)) - return Filename; - - // If that doesn't work, convert the name into a library name. - std::string LibName = "lib" + Filename; - - // Iterate over the directories in Paths to see if we can find the library - // there. - for (unsigned Index = 0; Index != Paths.size(); ++Index) { - std::string Directory = Paths[Index] + "/"; - - if (FileExists(Directory + LibName + ".bc")) - return Directory + LibName + ".bc"; - - if (FileExists(Directory + LibName + ".so")) - return Directory + LibName + ".so"; - - if (FileExists(Directory + LibName + ".a")) - return Directory + LibName + ".a"; - } - - // One last hope: Check LLVM_LIB_SEARCH_PATH. - char *SearchPath = getenv("LLVM_LIB_SEARCH_PATH"); - if (SearchPath == NULL) - return std::string(); - - LibName = std::string(SearchPath) + "/" + LibName; - if (FileExists(LibName)) - return LibName; - - return std::string(); -} +using namespace llvm; /// GetAllDefinedSymbols - Modifies its parameter DefinedSymbols to contain the /// name of each externally-visible symbol defined in M. /// -void GetAllDefinedSymbols(Module *M, std::set &DefinedSymbols) { +static void +GetAllDefinedSymbols(Module *M, std::set &DefinedSymbols) { for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) if (I->hasName() && !I->isExternal() && !I->hasInternalLinkage()) DefinedSymbols.insert(I->getName()); @@ -124,13 +50,10 @@ void GetAllDefinedSymbols(Module *M, std::set &DefinedSymbols) { /// UndefinedSymbols - A set of C++ strings containing the name of all /// undefined symbols. /// -/// Return value: -/// None. -/// -void +static void GetAllUndefinedSymbols(Module *M, std::set &UndefinedSymbols) { std::set DefinedSymbols; - UndefinedSymbols.clear(); // Start out empty + UndefinedSymbols.clear(); for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) if (I->hasName()) { @@ -156,287 +79,102 @@ GetAllUndefinedSymbols(Module *M, std::set &UndefinedSymbols) { ++I; // Keep this symbol in the undefined symbols list } - -/// LoadObject - reads the specified bytecode object file. -/// -/// Inputs: -/// FN - The name of the file to load. -/// -/// Outputs: -/// OutErrorMessage - The error message to give back to the caller. -/// -/// Return Value: -/// A pointer to a module represening the bytecode file is returned. -/// If an error occurs, the pointer is 0. -/// -std::auto_ptr -LoadObject(const std::string & FN, std::string &OutErrorMessage) { - std::string ErrorMessage; - Module *Result = ParseBytecodeFile(FN, &ErrorMessage); - if (Result) return std::auto_ptr(Result); - OutErrorMessage = "Bytecode file '" + FN + "' corrupt!"; - if (ErrorMessage.size()) OutErrorMessage += ": " + ErrorMessage; - return std::auto_ptr(); -} - /// LinkInArchive - opens an archive library and link in all objects which /// provide symbols that are currently undefined. /// /// Inputs: -/// M - The module in which to link the archives. /// Filename - The pathname of the archive. -/// Verbose - Flags whether verbose messages should be printed. -/// -/// Outputs: -/// ErrorMessage - A C++ string detailing what error occurred, if any. /// /// Return Value: /// TRUE - An error occurred. /// FALSE - No errors. -/// -static bool LinkInArchive(Module *M, - const std::string &Filename, - std::string &ErrorMessage, - bool Verbose) -{ +bool +Linker::LinkInArchive(const sys::Path &Filename) { + + // Make sure this is an archive file we're dealing with + if (!Filename.isArchive()) + return error("File '" + Filename.toString() + "' is not an archive."); + + // Open the archive file + verbose("Linking archive file '" + Filename.toString() + "'"); + // Find all of the symbols currently undefined in the bytecode program. // If all the symbols are defined, the program is complete, and there is // no reason to link in any archive files. std::set UndefinedSymbols; - GetAllUndefinedSymbols(M, UndefinedSymbols); + GetAllUndefinedSymbols(Composite, UndefinedSymbols); + if (UndefinedSymbols.empty()) { - if (Verbose) std::cerr << " No symbols undefined, don't link library!\n"; + verbose("No symbols undefined, skipping library '" + + Filename.toString() + "'"); return false; // No need to link anything in! } - // Load in the archive objects. - if (Verbose) std::cerr << " Loading archive file '" << Filename << "'\n"; - std::vector Objects; - if (ReadArchiveFile(Filename, Objects, &ErrorMessage)) - return true; + std::string ErrMsg; + std::auto_ptr AutoArch ( + Archive::OpenAndLoadSymbols(Filename,&ErrMsg)); - // Figure out which symbols are defined by all of the modules in the archive. - std::vector > DefinedSymbols; - DefinedSymbols.resize(Objects.size()); - for (unsigned i = 0; i != Objects.size(); ++i) { - GetAllDefinedSymbols(Objects[i], DefinedSymbols[i]); - } + Archive* arch = AutoArch.get(); - // While we are linking in object files, loop. - bool Linked = true; - while (Linked) { - Linked = false; + if (!arch) + return error("Cannot read archive '" + Filename.toString() + + "': " + ErrMsg); - for (unsigned i = 0; i != Objects.size(); ++i) { - // Consider whether we need to link in this module... we only need to - // link it in if it defines some symbol which is so far undefined. - // - const std::set &DefSymbols = DefinedSymbols[i]; + // Save a set of symbols that are not defined by the archive. Since we're + // entering a loop, there's no point searching for these multiple times. This + // variable is used to "set_subtract" from the set of undefined symbols. + std::set NotDefinedByArchive; - bool ObjectRequired = false; - for (std::set::iterator I = UndefinedSymbols.begin(), - E = UndefinedSymbols.end(); I != E; ++I) - if (DefSymbols.count(*I)) { - if (Verbose) - std::cerr << " Found object providing symbol '" << *I << "'...\n"; - ObjectRequired = true; - break; - } - - // We DO need to link this object into the program... - if (ObjectRequired) { - if (LinkModules(M, Objects[i], &ErrorMessage)) - return true; // Couldn't link in the right object file... - - // Since we have linked in this object, delete it from the list of - // objects to consider in this archive file. - std::swap(Objects[i], Objects.back()); - std::swap(DefinedSymbols[i], DefinedSymbols.back()); - Objects.pop_back(); - DefinedSymbols.pop_back(); - --i; // Do not skip an entry - - // The undefined symbols set should have shrunk. - GetAllUndefinedSymbols(M, UndefinedSymbols); - Linked = true; // We have linked something in! - } - } - } - - return false; -} - -/// LinkInFile - opens a bytecode file and links in all objects which -/// provide symbols that are currently undefined. -/// -/// Inputs: -/// HeadModule - The module in which to link the bytecode file. -/// Filename - The pathname of the bytecode file. -/// Verbose - Flags whether verbose messages should be printed. -/// -/// Outputs: -/// ErrorMessage - A C++ string detailing what error occurred, if any. -/// -/// Return Value: -/// TRUE - An error occurred. -/// FALSE - No errors. -/// -static bool LinkInFile(Module *HeadModule, - const std::string &Filename, - std::string &ErrorMessage, - bool Verbose) -{ - std::auto_ptr M(LoadObject(Filename, ErrorMessage)); - if (M.get() == 0) return true; - bool Result = LinkModules(HeadModule, M.get(), &ErrorMessage); - if (Verbose) std::cerr << "Linked in bytecode file '" << Filename << "'\n"; - return Result; -} - -/// LinkFiles - takes a module and a list of files and links them all together. -/// It locates the file either in the current directory, as its absolute -/// or relative pathname, or as a file somewhere in LLVM_LIB_SEARCH_PATH. -/// -/// Inputs: -/// progname - The name of the program (infamous argv[0]). -/// HeadModule - The module under which all files will be linked. -/// Files - A vector of C++ strings indicating the LLVM bytecode filenames -/// to be linked. The names can refer to a mixture of pure LLVM -/// bytecode files and archive (ar) formatted files. -/// Verbose - Flags whether verbose output should be printed while linking. -/// -/// Outputs: -/// HeadModule - The module will have the specified LLVM bytecode files linked -/// in. -/// -/// Return value: -/// FALSE - No errors. -/// TRUE - Some error occurred. -/// -bool LinkFiles(const char *progname, - Module *HeadModule, - const std::vector &Files, - bool Verbose) -{ - // String in which to receive error messages. - std::string ErrorMessage; + // While we are linking in object files, loop. + while (true) { - // Full pathname of the file - std::string Pathname; + // Find the modules we need to link into the target module + std::set Modules; + arch->findModulesDefiningSymbols(UndefinedSymbols, Modules); - // Get the library search path from the environment - char *SearchPath = getenv("LLVM_LIB_SEARCH_PATH"); + // If we didn't find any more modules to link this time, we are done + // searching this archive. + if (Modules.empty()) + break; - for (unsigned i = 0; i < Files.size(); ++i) { - // Determine where this file lives. - if (FileExists(Files[i])) { - Pathname = Files[i]; - } else { - if (SearchPath == NULL) { - std::cerr << progname << ": Cannot find linker input file '" - << Files[i] << "'\n"; - std::cerr << progname - << ": Warning: Your LLVM_LIB_SEARCH_PATH is unset.\n"; - return true; - } + // Any symbols remaining in UndefinedSymbols after + // findModulesDefiningSymbols are ones that the archive does not define. So + // we add them to the NotDefinedByArchive variable now. + NotDefinedByArchive.insert(UndefinedSymbols.begin(), + UndefinedSymbols.end()); - Pathname = std::string(SearchPath)+"/"+Files[i]; - if (!FileExists(Pathname)) { - std::cerr << progname << ": Cannot find linker input file '" - << Files[i] << "'\n"; - return true; - } - } + // Loop over all the ModuleProviders that we got back from the archive + for (std::set::iterator I=Modules.begin(), E=Modules.end(); + I != E; ++I) { - // A user may specify an ar archive without -l, perhaps because it - // is not installed as a library. Detect that and link the library. - if (IsArchive(Pathname)) { - if (Verbose) - std::cerr << "Trying to link archive '" << Pathname << "'\n"; + // Get the module we must link in. + std::auto_ptr AutoModule( (*I)->releaseModule() ); + Module* aModule = AutoModule.get(); - if (LinkInArchive(HeadModule, Pathname, ErrorMessage, Verbose)) { - PrintAndReturn(progname, ErrorMessage, - ": Error linking in archive '" + Pathname + "'"); - return true; - } - } else { - if (Verbose) - std::cerr << "Trying to link bytecode file '" << Pathname << "'\n"; + verbose(" Linking in module: " + aModule->getModuleIdentifier()); - if (LinkInFile(HeadModule, Pathname, ErrorMessage, Verbose)) { - PrintAndReturn(progname, ErrorMessage, - ": Error linking in bytecode file '" + Pathname + "'"); - return true; - } + // Link it in + if (LinkInModule(aModule)) + return error("Cannot link in module '" + + aModule->getModuleIdentifier() + "': " + Error); } - } - return false; -} - -/// LinkLibraries - takes the specified library files and links them into the -/// main bytecode object file. -/// -/// Inputs: -/// progname - The name of the program (infamous argv[0]). -/// HeadModule - The module into which all necessary libraries will be linked. -/// Libraries - The list of libraries to link into the module. -/// LibPaths - The list of library paths in which to find libraries. -/// Verbose - Flags whether verbose messages should be printed. -/// Native - Flags whether native code is being generated. -/// -/// Outputs: -/// HeadModule - The module will have all necessary libraries linked in. -/// -/// Return value: -/// FALSE - No error. -/// TRUE - Error. -/// -bool LinkLibraries(const char *progname, - Module *HeadModule, - const std::vector &Libraries, - const std::vector &LibPaths, - bool Verbose, - bool Native) -{ - // String in which to receive error messages. - std::string ErrorMessage; - - for (unsigned i = 0; i < Libraries.size(); ++i) { - // Determine where this library lives. - std::string Pathname = FindLib(Libraries[i], LibPaths); - if (Pathname.empty()) { - // If the pathname does not exist, then continue to the next one if - // we're doing a native link and give an error if we're doing a bytecode - // link. - if (!Native) { - PrintAndReturn(progname, "Cannot find library -l" + Libraries[i] + "\n"); - return true; - } - } - - // A user may specify an ar archive without -l, perhaps because it - // is not installed as a library. Detect that and link the library. - if (IsArchive(Pathname)) { - if (Verbose) - std::cerr << "Trying to link archive '" << Pathname << "' (-l" << Libraries[i] << ")\n"; - - if (LinkInArchive(HeadModule, Pathname, ErrorMessage, Verbose)) { - PrintAndReturn(progname, ErrorMessage, - ": Error linking in archive '" + Pathname + "' (-l" + Libraries[i] + ")"); - return true; - } - } else { - if (Verbose) - std::cerr << "Trying to link bytecode file '" << Pathname << "' (-l" << Libraries[i] << ")\n"; - - if (LinkInFile(HeadModule, Pathname, ErrorMessage, Verbose)) { - PrintAndReturn(progname, ErrorMessage, - ": error linking in bytecode file '" + Pathname + "' (-l" + Libraries[i] + ")"); - return true; - } - } + // Get the undefined symbols from the aggregate module. This recomputes the + // symbols we still need after the new modules have been linked in. + GetAllUndefinedSymbols(Composite, UndefinedSymbols); + + // At this point we have two sets of undefined symbols: UndefinedSymbols + // which holds the undefined symbols from all the modules, and + // NotDefinedByArchive which holds symbols we know the archive doesn't + // define. There's no point searching for symbols that we won't find in the + // archive so we subtract these sets. + set_subtract(UndefinedSymbols, NotDefinedByArchive); + + // If there's no symbols left, no point in continuing to search the + // archive. + if (UndefinedSymbols.empty()) + break; } - + return false; }