diff options
Diffstat (limited to 'ELF/Driver.cpp')
| -rw-r--r-- | ELF/Driver.cpp | 485 |
1 files changed, 275 insertions, 210 deletions
diff --git a/ELF/Driver.cpp b/ELF/Driver.cpp index 47a50bb725e7..2b6925031b07 100644 --- a/ELF/Driver.cpp +++ b/ELF/Driver.cpp @@ -25,23 +25,25 @@ #include "Driver.h" #include "Config.h" -#include "Error.h" #include "Filesystem.h" #include "ICF.h" #include "InputFiles.h" #include "InputSection.h" #include "LinkerScript.h" -#include "Memory.h" #include "OutputSections.h" #include "ScriptParser.h" #include "Strings.h" #include "SymbolTable.h" +#include "Symbols.h" #include "SyntheticSections.h" #include "Target.h" -#include "Threads.h" #include "Writer.h" -#include "lld/Config/Version.h" -#include "lld/Driver/Driver.h" +#include "lld/Common/Args.h" +#include "lld/Common/Driver.h" +#include "lld/Common/ErrorHandler.h" +#include "lld/Common/Memory.h" +#include "lld/Common/Threads.h" +#include "lld/Common/Version.h" #include "llvm/ADT/StringExtras.h" #include "llvm/ADT/StringSwitch.h" #include "llvm/Support/CommandLine.h" @@ -64,27 +66,40 @@ using namespace lld::elf; Configuration *elf::Config; LinkerDriver *elf::Driver; -BumpPtrAllocator elf::BAlloc; -StringSaver elf::Saver{BAlloc}; -std::vector<SpecificAllocBase *> elf::SpecificAllocBase::Instances; - static void setConfigs(); bool elf::link(ArrayRef<const char *> Args, bool CanExitEarly, raw_ostream &Error) { - ErrorCount = 0; - ErrorOS = &Error; + errorHandler().LogName = Args[0]; + errorHandler().ErrorLimitExceededMsg = + "too many errors emitted, stopping now (use " + "-error-limit=0 to see all errors)"; + errorHandler().ErrorOS = &Error; + errorHandler().ColorDiagnostics = Error.has_colors(); InputSections.clear(); + OutputSections.clear(); Tar = nullptr; + BinaryFiles.clear(); + BitcodeFiles.clear(); + ObjectFiles.clear(); + SharedFiles.clear(); Config = make<Configuration>(); Driver = make<LinkerDriver>(); Script = make<LinkerScript>(); + Symtab = make<SymbolTable>(); Config->Argv = {Args.begin(), Args.end()}; Driver->main(Args, CanExitEarly); + + // Exit immediately if we don't need to return to the caller. + // This saves time because the overhead of calling destructors + // for all globally-allocated objects is not negligible. + if (Config->ExitEarly) + exitLld(errorCount() ? 1 : 0); + freeArena(); - return !ErrorCount; + return !errorCount(); } // Parses a linker -m option. @@ -112,12 +127,8 @@ static std::tuple<ELFKind, uint16_t, uint8_t> parseEmulation(StringRef Emul) { .Case("elf_iamcu", {ELF32LEKind, EM_IAMCU}) .Default({ELFNoneKind, EM_NONE}); - if (Ret.first == ELFNoneKind) { - if (S == "i386pe" || S == "i386pep" || S == "thumb2pe") - error("Windows targets are not supported on the ELF frontend: " + Emul); - else - error("unknown emulation: " + Emul); - } + if (Ret.first == ELFNoneKind) + error("unknown emulation: " + Emul); return std::make_tuple(Ret.first, Ret.second, OSABI); } @@ -126,19 +137,22 @@ static std::tuple<ELFKind, uint16_t, uint8_t> parseEmulation(StringRef Emul) { std::vector<std::pair<MemoryBufferRef, uint64_t>> static getArchiveMembers( MemoryBufferRef MB) { std::unique_ptr<Archive> File = - check(Archive::create(MB), + CHECK(Archive::create(MB), MB.getBufferIdentifier() + ": failed to parse archive"); std::vector<std::pair<MemoryBufferRef, uint64_t>> V; Error Err = Error::success(); + bool AddToTar = File->isThin() && Tar; for (const ErrorOr<Archive::Child> &COrErr : File->children(Err)) { Archive::Child C = - check(COrErr, MB.getBufferIdentifier() + + CHECK(COrErr, MB.getBufferIdentifier() + ": could not get the child of the archive"); MemoryBufferRef MBRef = - check(C.getMemoryBufferRef(), + CHECK(C.getMemoryBufferRef(), MB.getBufferIdentifier() + ": could not get the buffer for a child of the archive"); + if (AddToTar) + Tar->append(relativeToRoot(check(C.getFullName())), MBRef.getBuffer()); V.push_back(std::make_pair(MBRef, C.getChildOffset())); } if (Err) @@ -179,7 +193,7 @@ void LinkerDriver::addFile(StringRef Path, bool WithLOption) { } std::unique_ptr<Archive> File = - check(Archive::create(MBRef), Path + ": failed to parse archive"); + CHECK(Archive::create(MBRef), Path + ": failed to parse archive"); // If an archive file has no symbol table, it is likely that a user // is attempting LTO and using a default ar command that doesn't @@ -187,7 +201,7 @@ void LinkerDriver::addFile(StringRef Path, bool WithLOption) { // we'll handle it as if it had a symbol table. if (!File->isEmpty() && !File->hasSymbolTable()) { for (const auto &P : getArchiveMembers(MBRef)) - Files.push_back(make<LazyObjectFile>(P.first, Path, P.second)); + Files.push_back(make<LazyObjFile>(P.first, Path, P.second)); return; } @@ -216,7 +230,7 @@ void LinkerDriver::addFile(StringRef Path, bool WithLOption) { return; default: if (InLib) - Files.push_back(make<LazyObjectFile>(MBRef, "", 0)); + Files.push_back(make<LazyObjFile>(MBRef, "", 0)); else Files.push_back(createObjectFile(MBRef)); } @@ -256,6 +270,9 @@ static void checkOptions(opt::InputArgList &Args) { if (Config->EMachine == EM_MIPS && Config->GnuHash) error("the .gnu.hash section is not compatible with the MIPS target."); + if (Config->FixCortexA53Errata843419 && Config->EMachine != EM_AARCH64) + error("--fix-cortex-a53-843419 is only supported on AArch64 targets."); + if (Config->Pie && Config->Shared) error("-shared and -pie may not be used together"); @@ -265,6 +282,9 @@ static void checkOptions(opt::InputArgList &Args) { if (!Config->Shared && !Config->AuxiliaryList.empty()) error("-f may not be used without -shared"); + if (!Config->Relocatable && !Config->DefineCommon) + error("-no-define-common not supported in non relocatable output"); + if (Config->Relocatable) { if (Config->Shared) error("-r and -shared may not be used together"); @@ -277,16 +297,6 @@ static void checkOptions(opt::InputArgList &Args) { } } -static int getInteger(opt::InputArgList &Args, unsigned Key, int Default) { - int V = Default; - if (auto *Arg = Args.getLastArg(Key)) { - StringRef S = Arg->getValue(); - if (!to_integer(S, V, 10)) - error(Arg->getSpelling() + ": number expected, but got " + S); - } - return V; -} - static const char *getReproduceOption(opt::InputArgList &Args) { if (auto *Arg = Args.getLastArg(OPT_reproduce)) return Arg->getValue(); @@ -300,26 +310,12 @@ static bool hasZOption(opt::InputArgList &Args, StringRef Key) { return false; } -static uint64_t getZOptionValue(opt::InputArgList &Args, StringRef Key, - uint64_t Default) { - for (auto *Arg : Args.filtered(OPT_z)) { - std::pair<StringRef, StringRef> KV = StringRef(Arg->getValue()).split('='); - if (KV.first == Key) { - uint64_t Result = Default; - if (!to_integer(KV.second, Result)) - error("invalid " + Key + ": " + KV.second); - return Result; - } - } - return Default; -} - void LinkerDriver::main(ArrayRef<const char *> ArgsArr, bool CanExitEarly) { ELFOptTable Parser; opt::InputArgList Args = Parser.parse(ArgsArr.slice(1)); // Interpret this flag early because error() depends on them. - Config->ErrorLimit = getInteger(Args, OPT_error_limit, 20); + errorHandler().ErrorLimit = args::getInteger(Args, OPT_error_limit, 20); // Handle -help if (Args.hasArg(OPT_help)) { @@ -345,13 +341,15 @@ void LinkerDriver::main(ArrayRef<const char *> ArgsArr, bool CanExitEarly) { if (Args.hasArg(OPT_v) || Args.hasArg(OPT_version)) message(getLLDVersion() + " (compatible with GNU linkers)"); - // ld.bfd always exits after printing out the version string. - // ld.gold proceeds if a given option is -v. Because gold's behavior - // is more permissive than ld.bfd, we chose what gold does here. + // The behavior of -v or --version is a bit strange, but this is + // needed for compatibility with GNU linkers. + if (Args.hasArg(OPT_v) && !Args.hasArg(OPT_INPUT)) + return; if (Args.hasArg(OPT_version)) return; Config->ExitEarly = CanExitEarly && !Args.hasArg(OPT_full_shutdown); + errorHandler().ExitEarly = Config->ExitEarly; if (const char *Path = getReproduceOption(Args)) { // Note that --reproduce is a debug option so you can ignore it @@ -375,7 +373,7 @@ void LinkerDriver::main(ArrayRef<const char *> ArgsArr, bool CanExitEarly) { inferMachineType(); setConfigs(); checkOptions(Args); - if (ErrorCount) + if (errorCount()) return; switch (Config->EKind) { @@ -396,36 +394,19 @@ void LinkerDriver::main(ArrayRef<const char *> ArgsArr, bool CanExitEarly) { } } -static bool getArg(opt::InputArgList &Args, unsigned K1, unsigned K2, - bool Default) { - if (auto *Arg = Args.getLastArg(K1, K2)) - return Arg->getOption().getID() == K1; - return Default; -} - -static std::vector<StringRef> getArgs(opt::InputArgList &Args, int Id) { - std::vector<StringRef> V; - for (auto *Arg : Args.filtered(Id)) - V.push_back(Arg->getValue()); - return V; -} - static std::string getRpath(opt::InputArgList &Args) { - std::vector<StringRef> V = getArgs(Args, OPT_rpath); + std::vector<StringRef> V = args::getStrings(Args, OPT_rpath); return llvm::join(V.begin(), V.end(), ":"); } // Determines what we should do if there are remaining unresolved // symbols after the name resolution. static UnresolvedPolicy getUnresolvedSymbolPolicy(opt::InputArgList &Args) { - // -noinhibit-exec or -r imply some default values. - if (Args.hasArg(OPT_noinhibit_exec)) - return UnresolvedPolicy::WarnAll; if (Args.hasArg(OPT_relocatable)) return UnresolvedPolicy::IgnoreAll; - UnresolvedPolicy ErrorOrWarn = getArg(Args, OPT_error_unresolved_symbols, - OPT_warn_unresolved_symbols, true) + UnresolvedPolicy ErrorOrWarn = Args.hasFlag(OPT_error_unresolved_symbols, + OPT_warn_unresolved_symbols, true) ? UnresolvedPolicy::ReportError : UnresolvedPolicy::Warn; @@ -513,7 +494,7 @@ static StripPolicy getStrip(opt::InputArgList &Args) { return StripPolicy::Debug; } -static uint64_t parseSectionAddress(StringRef S, opt::Arg *Arg) { +static uint64_t parseSectionAddress(StringRef S, const opt::Arg &Arg) { uint64_t VA = 0; if (S.startswith("0x")) S = S.drop_front(2); @@ -528,15 +509,15 @@ static StringMap<uint64_t> getSectionStartMap(opt::InputArgList &Args) { StringRef Name; StringRef Addr; std::tie(Name, Addr) = StringRef(Arg->getValue()).split('='); - Ret[Name] = parseSectionAddress(Addr, Arg); + Ret[Name] = parseSectionAddress(Addr, *Arg); } if (auto *Arg = Args.getLastArg(OPT_Ttext)) - Ret[".text"] = parseSectionAddress(Arg->getValue(), Arg); + Ret[".text"] = parseSectionAddress(Arg->getValue(), *Arg); if (auto *Arg = Args.getLastArg(OPT_Tdata)) - Ret[".data"] = parseSectionAddress(Arg->getValue(), Arg); + Ret[".data"] = parseSectionAddress(Arg->getValue(), *Arg); if (auto *Arg = Args.getLastArg(OPT_Tbss)) - Ret[".bss"] = parseSectionAddress(Arg->getValue(), Arg); + Ret[".bss"] = parseSectionAddress(Arg->getValue(), *Arg); return Ret; } @@ -551,15 +532,15 @@ static SortSectionPolicy getSortSection(opt::InputArgList &Args) { return SortSectionPolicy::Default; } -static std::pair<bool, bool> getHashStyle(opt::InputArgList &Args) { - StringRef S = Args.getLastArgValue(OPT_hash_style, "sysv"); - if (S == "sysv") - return {true, false}; - if (S == "gnu") - return {false, true}; - if (S != "both") - error("unknown -hash-style: " + S); - return {true, true}; +static OrphanHandlingPolicy getOrphanHandling(opt::InputArgList &Args) { + StringRef S = Args.getLastArgValue(OPT_orphan_handling, "place"); + if (S == "warn") + return OrphanHandlingPolicy::Warn; + if (S == "error") + return OrphanHandlingPolicy::Error; + if (S != "place") + error("unknown --orphan-handling mode: " + S); + return OrphanHandlingPolicy::Place; } // Parse --build-id or --build-id=<style>. We handle "tree" as a @@ -589,19 +570,6 @@ getBuildId(opt::InputArgList &Args) { return {BuildIdKind::None, {}}; } -static std::vector<StringRef> getLines(MemoryBufferRef MB) { - SmallVector<StringRef, 0> Arr; - MB.getBuffer().split(Arr, '\n'); - - std::vector<StringRef> Ret; - for (StringRef S : Arr) { - S = S.trim(); - if (!S.empty()) - Ret.push_back(S); - } - return Ret; -} - static bool getCompressDebugSections(opt::InputArgList &Args) { StringRef S = Args.getLastArgValue(OPT_compress_debug_sections, "none"); if (S == "none") @@ -613,53 +581,70 @@ static bool getCompressDebugSections(opt::InputArgList &Args) { return true; } +static int parseInt(StringRef S, opt::Arg *Arg) { + int V = 0; + if (!to_integer(S, V, 10)) + error(Arg->getSpelling() + ": number expected, but got '" + S + "'"); + return V; +} + // Initializes Config members by the command line options. void LinkerDriver::readConfigs(opt::InputArgList &Args) { - Config->AllowMultipleDefinition = Args.hasArg(OPT_allow_multiple_definition); - Config->AuxiliaryList = getArgs(Args, OPT_auxiliary); + Config->AllowMultipleDefinition = + Args.hasArg(OPT_allow_multiple_definition) || hasZOption(Args, "muldefs"); + Config->AuxiliaryList = args::getStrings(Args, OPT_auxiliary); Config->Bsymbolic = Args.hasArg(OPT_Bsymbolic); Config->BsymbolicFunctions = Args.hasArg(OPT_Bsymbolic_functions); + Config->Chroot = Args.getLastArgValue(OPT_chroot); Config->CompressDebugSections = getCompressDebugSections(Args); - Config->DefineCommon = getArg(Args, OPT_define_common, OPT_no_define_common, - !Args.hasArg(OPT_relocatable)); - Config->Demangle = getArg(Args, OPT_demangle, OPT_no_demangle, true); + Config->DefineCommon = Args.hasFlag(OPT_define_common, OPT_no_define_common, + !Args.hasArg(OPT_relocatable)); + Config->Demangle = Args.hasFlag(OPT_demangle, OPT_no_demangle, true); Config->DisableVerify = Args.hasArg(OPT_disable_verify); Config->Discard = getDiscard(Args); Config->DynamicLinker = getDynamicLinker(Args); - Config->EhFrameHdr = Args.hasArg(OPT_eh_frame_hdr); + Config->EhFrameHdr = + Args.hasFlag(OPT_eh_frame_hdr, OPT_no_eh_frame_hdr, false); Config->EmitRelocs = Args.hasArg(OPT_emit_relocs); Config->EnableNewDtags = !Args.hasArg(OPT_disable_new_dtags); Config->Entry = Args.getLastArgValue(OPT_entry); Config->ExportDynamic = - getArg(Args, OPT_export_dynamic, OPT_no_export_dynamic, false); - Config->FatalWarnings = - getArg(Args, OPT_fatal_warnings, OPT_no_fatal_warnings, false); - Config->FilterList = getArgs(Args, OPT_filter); + Args.hasFlag(OPT_export_dynamic, OPT_no_export_dynamic, false); + errorHandler().FatalWarnings = + Args.hasFlag(OPT_fatal_warnings, OPT_no_fatal_warnings, false); + Config->FilterList = args::getStrings(Args, OPT_filter); Config->Fini = Args.getLastArgValue(OPT_fini, "_fini"); - Config->GcSections = getArg(Args, OPT_gc_sections, OPT_no_gc_sections, false); - Config->GdbIndex = Args.hasArg(OPT_gdb_index); - Config->ICF = getArg(Args, OPT_icf_all, OPT_icf_none, false); + Config->FixCortexA53Errata843419 = Args.hasArg(OPT_fix_cortex_a53_843419); + Config->GcSections = Args.hasFlag(OPT_gc_sections, OPT_no_gc_sections, false); + Config->GdbIndex = Args.hasFlag(OPT_gdb_index, OPT_no_gdb_index, false); + Config->ICF = Args.hasFlag(OPT_icf_all, OPT_icf_none, false); + Config->ICFData = Args.hasArg(OPT_icf_data); Config->Init = Args.getLastArgValue(OPT_init, "_init"); Config->LTOAAPipeline = Args.getLastArgValue(OPT_lto_aa_pipeline); Config->LTONewPmPasses = Args.getLastArgValue(OPT_lto_newpm_passes); - Config->LTOO = getInteger(Args, OPT_lto_O, 2); - Config->LTOPartitions = getInteger(Args, OPT_lto_partitions, 1); + Config->LTOO = args::getInteger(Args, OPT_lto_O, 2); + Config->LTOPartitions = args::getInteger(Args, OPT_lto_partitions, 1); Config->MapFile = Args.getLastArgValue(OPT_Map); Config->NoGnuUnique = Args.hasArg(OPT_no_gnu_unique); + Config->MergeArmExidx = + Args.hasFlag(OPT_merge_exidx_entries, OPT_no_merge_exidx_entries, true); Config->NoUndefinedVersion = Args.hasArg(OPT_no_undefined_version); + Config->NoinhibitExec = Args.hasArg(OPT_noinhibit_exec); Config->Nostdlib = Args.hasArg(OPT_nostdlib); Config->OFormatBinary = isOutputFormatBinary(Args); - Config->Omagic = Args.hasArg(OPT_omagic); + Config->Omagic = Args.hasFlag(OPT_omagic, OPT_no_omagic, false); Config->OptRemarksFilename = Args.getLastArgValue(OPT_opt_remarks_filename); Config->OptRemarksWithHotness = Args.hasArg(OPT_opt_remarks_with_hotness); - Config->Optimize = getInteger(Args, OPT_O, 1); + Config->Optimize = args::getInteger(Args, OPT_O, 1); + Config->OrphanHandling = getOrphanHandling(Args); Config->OutputFile = Args.getLastArgValue(OPT_o); - Config->Pie = getArg(Args, OPT_pie, OPT_nopie, false); - Config->PrintGcSections = Args.hasArg(OPT_print_gc_sections); + Config->Pie = Args.hasFlag(OPT_pie, OPT_nopie, false); + Config->PrintGcSections = + Args.hasFlag(OPT_print_gc_sections, OPT_no_print_gc_sections, false); Config->Rpath = getRpath(Args); Config->Relocatable = Args.hasArg(OPT_relocatable); Config->SaveTemps = Args.hasArg(OPT_save_temps); - Config->SearchPaths = getArgs(Args, OPT_L); + Config->SearchPaths = args::getStrings(Args, OPT_library_path); Config->SectionStartMap = getSectionStartMap(Args); Config->Shared = Args.hasArg(OPT_shared); Config->SingleRoRx = Args.hasArg(OPT_no_rosegment); @@ -667,18 +652,19 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) { Config->SortSection = getSortSection(Args); Config->Strip = getStrip(Args); Config->Sysroot = Args.getLastArgValue(OPT_sysroot); - Config->Target1Rel = getArg(Args, OPT_target1_rel, OPT_target1_abs, false); + Config->Target1Rel = Args.hasFlag(OPT_target1_rel, OPT_target1_abs, false); Config->Target2 = getTarget2(Args); Config->ThinLTOCacheDir = Args.getLastArgValue(OPT_thinlto_cache_dir); - Config->ThinLTOCachePolicy = check( + Config->ThinLTOCachePolicy = CHECK( parseCachePruningPolicy(Args.getLastArgValue(OPT_thinlto_cache_policy)), "--thinlto-cache-policy: invalid cache policy"); - Config->ThinLTOJobs = getInteger(Args, OPT_thinlto_jobs, -1u); - Config->Threads = getArg(Args, OPT_threads, OPT_no_threads, true); + Config->ThinLTOJobs = args::getInteger(Args, OPT_thinlto_jobs, -1u); + ThreadsEnabled = Args.hasFlag(OPT_threads, OPT_no_threads, true); Config->Trace = Args.hasArg(OPT_trace); - Config->Undefined = getArgs(Args, OPT_undefined); + Config->Undefined = args::getStrings(Args, OPT_undefined); Config->UnresolvedSymbols = getUnresolvedSymbolPolicy(Args); Config->Verbose = Args.hasArg(OPT_verbose); + errorHandler().Verbose = Config->Verbose; Config->WarnCommon = Args.hasArg(OPT_warn_common); Config->ZCombreloc = !hasZOption(Args, "nocombreloc"); Config->ZExecstack = hasZOption(Args, "execstack"); @@ -689,20 +675,39 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) { Config->ZOrigin = hasZOption(Args, "origin"); Config->ZRelro = !hasZOption(Args, "norelro"); Config->ZRodynamic = hasZOption(Args, "rodynamic"); - Config->ZStackSize = getZOptionValue(Args, "stack-size", 0); + Config->ZStackSize = args::getZOptionValue(Args, OPT_z, "stack-size", 0); Config->ZText = !hasZOption(Args, "notext"); Config->ZWxneeded = hasZOption(Args, "wxneeded"); + // Parse LTO plugin-related options for compatibility with gold. + for (auto *Arg : Args.filtered(OPT_plugin_opt, OPT_plugin_opt_eq)) { + StringRef S = Arg->getValue(); + if (S == "disable-verify") + Config->DisableVerify = true; + else if (S == "save-temps") + Config->SaveTemps = true; + else if (S.startswith("O")) + Config->LTOO = parseInt(S.substr(1), Arg); + else if (S.startswith("lto-partitions=")) + Config->LTOPartitions = parseInt(S.substr(15), Arg); + else if (S.startswith("jobs=")) + Config->ThinLTOJobs = parseInt(S.substr(5), Arg); + else if (!S.startswith("/") && !S.startswith("-fresolution=") && + !S.startswith("-pass-through=") && !S.startswith("mcpu=") && + !S.startswith("thinlto") && S != "-function-sections" && + S != "-data-sections") + error(Arg->getSpelling() + ": unknown option: " + S); + } + if (Config->LTOO > 3) - error("invalid optimization level for LTO: " + - Args.getLastArgValue(OPT_lto_O)); + error("invalid optimization level for LTO: " + Twine(Config->LTOO)); if (Config->LTOPartitions == 0) error("--lto-partitions: number of threads must be > 0"); if (Config->ThinLTOJobs == 0) error("--thinlto-jobs: number of threads must be > 0"); + // Parse ELF{32,64}{LE,BE} and CPU type. if (auto *Arg = Args.getLastArg(OPT_m)) { - // Parse ELF{32,64}{LE,BE} and CPU type. StringRef S = Arg->getValue(); std::tie(Config->EKind, Config->EMachine, Config->OSABI) = parseEmulation(S); @@ -710,6 +715,19 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) { Config->Emulation = S; } + // Parse -hash-style={sysv,gnu,both}. + if (auto *Arg = Args.getLastArg(OPT_hash_style)) { + StringRef S = Arg->getValue(); + if (S == "sysv") + Config->SysvHash = true; + else if (S == "gnu") + Config->GnuHash = true; + else if (S == "both") + Config->SysvHash = Config->GnuHash = true; + else + error("unknown -hash-style: " + S); + } + if (Args.hasArg(OPT_print_map)) Config->MapFile = "-"; @@ -720,25 +738,32 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) { if (Config->Omagic) Config->ZRelro = false; - std::tie(Config->SysvHash, Config->GnuHash) = getHashStyle(Args); std::tie(Config->BuildId, Config->BuildIdVector) = getBuildId(Args); + if (auto *Arg = Args.getLastArg(OPT_pack_dyn_relocs_eq)) { + StringRef S = Arg->getValue(); + if (S == "android") + Config->AndroidPackDynRelocs = true; + else if (S != "none") + error("unknown -pack-dyn-relocs format: " + S); + } + if (auto *Arg = Args.getLastArg(OPT_symbol_ordering_file)) if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue())) - Config->SymbolOrderingFile = getLines(*Buffer); + Config->SymbolOrderingFile = args::getLines(*Buffer); // If --retain-symbol-file is used, we'll keep only the symbols listed in // the file and discard all others. if (auto *Arg = Args.getLastArg(OPT_retain_symbols_file)) { Config->DefaultSymbolVersion = VER_NDX_LOCAL; if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue())) - for (StringRef S : getLines(*Buffer)) + for (StringRef S : args::getLines(*Buffer)) Config->VersionScriptGlobals.push_back( {S, /*IsExternCpp*/ false, /*HasWildcard*/ false}); } bool HasExportDynamic = - getArg(Args, OPT_export_dynamic, OPT_no_export_dynamic, false); + Args.hasFlag(OPT_export_dynamic, OPT_no_export_dynamic, false); // Parses -dynamic-list and -export-dynamic-symbol. They make some // symbols private. Note that -export-dynamic takes precedence over them @@ -749,21 +774,11 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) { readDynamicList(*Buffer); for (auto *Arg : Args.filtered(OPT_export_dynamic_symbol)) - Config->VersionScriptGlobals.push_back( + Config->DynamicList.push_back( {Arg->getValue(), /*IsExternCpp*/ false, /*HasWildcard*/ false}); - - // Dynamic lists are a simplified linker script that doesn't need the - // "global:" and implicitly ends with a "local:*". Set the variables - // needed to simulate that. - if (Args.hasArg(OPT_dynamic_list) || - Args.hasArg(OPT_export_dynamic_symbol)) { - Config->ExportDynamic = true; - if (!Config->Shared) - Config->DefaultSymbolVersion = VER_NDX_LOCAL; - } } - if (auto *Arg = Args.getLastArg(OPT_version_script)) + for (auto *Arg : Args.filtered(OPT_version_script)) if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue())) readVersionScript(*Buffer); } @@ -804,17 +819,20 @@ static bool getBinaryOption(StringRef S) { void LinkerDriver::createFiles(opt::InputArgList &Args) { for (auto *Arg : Args) { - switch (Arg->getOption().getID()) { - case OPT_l: + switch (Arg->getOption().getUnaliasedOption().getID()) { + case OPT_library: addLibrary(Arg->getValue()); break; case OPT_INPUT: addFile(Arg->getValue(), /*WithLOption=*/false); break; - case OPT_alias_script_T: case OPT_script: - if (Optional<MemoryBufferRef> MB = readFile(Arg->getValue())) - readLinkerScript(*MB); + if (Optional<std::string> Path = searchLinkerScript(Arg->getValue())) { + if (Optional<MemoryBufferRef> MB = readFile(*Path)) + readLinkerScript(*MB); + break; + } + error(Twine("cannot find linker script ") + Arg->getValue()); break; case OPT_as_needed: Config->AsNeeded = true; @@ -846,7 +864,7 @@ void LinkerDriver::createFiles(opt::InputArgList &Args) { } } - if (Files.empty() && ErrorCount == 0) + if (Files.empty() && errorCount() == 0) error("no input files"); } @@ -870,21 +888,20 @@ void LinkerDriver::inferMachineType() { // Parse -z max-page-size=<value>. The default value is defined by // each target. static uint64_t getMaxPageSize(opt::InputArgList &Args) { - uint64_t Val = - getZOptionValue(Args, "max-page-size", Target->DefaultMaxPageSize); + uint64_t Val = args::getZOptionValue(Args, OPT_z, "max-page-size", + Target->DefaultMaxPageSize); if (!isPowerOf2_64(Val)) error("max-page-size: value isn't a power of 2"); return Val; } // Parses -image-base option. -static uint64_t getImageBase(opt::InputArgList &Args) { - // Use default if no -image-base option is given. - // Because we are using "Target" here, this function - // has to be called after the variable is initialized. +static Optional<uint64_t> getImageBase(opt::InputArgList &Args) { + // Because we are using "Config->MaxPageSize" here, this function has to be + // called after the variable is initialized. auto *Arg = Args.getLastArg(OPT_image_base); if (!Arg) - return Config->Pic ? 0 : Target->DefaultImageBase; + return None; StringRef S = Arg->getValue(); uint64_t V; @@ -897,21 +914,6 @@ static uint64_t getImageBase(opt::InputArgList &Args) { return V; } -// Parses --defsym=alias option. -static std::vector<std::pair<StringRef, StringRef>> -getDefsym(opt::InputArgList &Args) { - std::vector<std::pair<StringRef, StringRef>> Ret; - for (auto *Arg : Args.filtered(OPT_defsym)) { - StringRef From; - StringRef To; - std::tie(From, To) = StringRef(Arg->getValue()).split('='); - if (!isValidCIdentifier(To)) - error("--defsym: symbol name expected, but got " + To); - Ret.push_back({From, To}); - } - return Ret; -} - // Parses `--exclude-libs=lib,lib,...`. // The library names may be delimited by commas or colons. static DenseSet<StringRef> getExcludeLibs(opt::InputArgList &Args) { @@ -930,33 +932,50 @@ static DenseSet<StringRef> getExcludeLibs(opt::InputArgList &Args) { return Ret; } +static Optional<StringRef> getArchiveName(InputFile *File) { + if (isa<ArchiveFile>(File)) + return File->getName(); + if (!File->ArchiveName.empty()) + return File->ArchiveName; + return None; +} + // Handles the -exclude-libs option. If a static library file is specified // by the -exclude-libs option, all public symbols from the archive become // private unless otherwise specified by version scripts or something. // A special library name "ALL" means all archive files. // // This is not a popular option, but some programs such as bionic libc use it. +template <class ELFT> static void excludeLibs(opt::InputArgList &Args, ArrayRef<InputFile *> Files) { DenseSet<StringRef> Libs = getExcludeLibs(Args); bool All = Libs.count("ALL"); for (InputFile *File : Files) - if (auto *F = dyn_cast<ArchiveFile>(File)) - if (All || Libs.count(path::filename(F->getName()))) - for (Symbol *Sym : F->getSymbols()) - Sym->VersionId = VER_NDX_LOCAL; + if (Optional<StringRef> Archive = getArchiveName(File)) + if (All || Libs.count(path::filename(*Archive))) + for (Symbol *Sym : File->getSymbols()) + if (!Sym->isLocal()) + Sym->VersionId = VER_NDX_LOCAL; } // Do actual linking. Note that when this function is called, // all linker scripts have already been parsed. template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) { - SymbolTable<ELFT> Symtab; - elf::Symtab<ELFT>::X = &Symtab; Target = getTarget(); Config->MaxPageSize = getMaxPageSize(Args); Config->ImageBase = getImageBase(Args); + // If a -hash-style option was not given, set to a default value, + // which varies depending on the target. + if (!Args.hasArg(OPT_hash_style)) { + if (Config->EMachine == EM_MIPS) + Config->SysvHash = true; + else + Config->SysvHash = Config->GnuHash = true; + } + // Default output filename is "a.out" by the Unix tradition. if (Config->OutputFile.empty()) Config->OutputFile = "a.out"; @@ -968,7 +987,7 @@ template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) { error("cannot open output file " + Config->OutputFile + ": " + E.message()); if (auto E = tryCreateFile(Config->MapFile)) error("cannot open map file " + Config->MapFile + ": " + E.message()); - if (ErrorCount) + if (errorCount()) return; // Use default entry point name if no name was given via the command @@ -981,67 +1000,113 @@ template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) { // Handle --trace-symbol. for (auto *Arg : Args.filtered(OPT_trace_symbol)) - Symtab.trace(Arg->getValue()); + Symtab->trace(Arg->getValue()); // Add all files to the symbol table. This will add almost all // symbols that we need to the symbol table. for (InputFile *F : Files) - Symtab.addFile(F); + Symtab->addFile<ELFT>(F); + + // Process -defsym option. + for (auto *Arg : Args.filtered(OPT_defsym)) { + StringRef From; + StringRef To; + std::tie(From, To) = StringRef(Arg->getValue()).split('='); + readDefsym(From, MemoryBufferRef(To, "-defsym")); + } + + // Now that we have every file, we can decide if we will need a + // dynamic symbol table. + // We need one if we were asked to export dynamic symbols or if we are + // producing a shared library. + // We also need one if any shared libraries are used and for pie executables + // (probably because the dynamic linker needs it). + Config->HasDynSymTab = + !SharedFiles.empty() || Config->Pic || Config->ExportDynamic; + + // Some symbols (such as __ehdr_start) are defined lazily only when there + // are undefined symbols for them, so we add these to trigger that logic. + for (StringRef Sym : Script->ReferencedSymbols) + Symtab->addUndefined<ELFT>(Sym); + + // Handle the `--undefined <sym>` options. + for (StringRef S : Config->Undefined) + Symtab->fetchIfLazy<ELFT>(S); // If an entry symbol is in a static archive, pull out that file now // to complete the symbol table. After this, no new names except a // few linker-synthesized ones will be added to the symbol table. - if (Symtab.find(Config->Entry)) - Symtab.addUndefined(Config->Entry); + Symtab->fetchIfLazy<ELFT>(Config->Entry); // Return if there were name resolution errors. - if (ErrorCount) + if (errorCount()) return; - // Handle the `--undefined <sym>` options. - Symtab.scanUndefinedFlags(); - // Handle undefined symbols in DSOs. - Symtab.scanShlibUndefined(); + Symtab->scanShlibUndefined<ELFT>(); // Handle the -exclude-libs option. if (Args.hasArg(OPT_exclude_libs)) - excludeLibs(Args, Files); + excludeLibs<ELFT>(Args, Files); + + // Create ElfHeader early. We need a dummy section in + // addReservedSymbols to mark the created symbols as not absolute. + Out::ElfHeader = make<OutputSection>("", 0, SHF_ALLOC); + Out::ElfHeader->Size = sizeof(typename ELFT::Ehdr); + + // We need to create some reserved symbols such as _end. Create them. + if (!Config->Relocatable) + addReservedSymbols<ELFT>(); // Apply version scripts. - Symtab.scanVersionScript(); + Symtab->scanVersionScript(); // Create wrapped symbols for -wrap option. for (auto *Arg : Args.filtered(OPT_wrap)) - Symtab.addSymbolWrap(Arg->getValue()); - - // Create alias symbols for -defsym option. - for (std::pair<StringRef, StringRef> &Def : getDefsym(Args)) - Symtab.addSymbolAlias(Def.first, Def.second); + Symtab->addSymbolWrap<ELFT>(Arg->getValue()); - Symtab.addCombinedLTOObject(); - if (ErrorCount) + Symtab->addCombinedLTOObject<ELFT>(); + if (errorCount()) return; - // Some symbols (such as __ehdr_start) are defined lazily only when there - // are undefined symbols for them, so we add these to trigger that logic. - for (StringRef Sym : Script->Opt.ReferencedSymbols) - Symtab.addUndefined(Sym); - - // Apply symbol renames for -wrap and -defsym - Symtab.applySymbolRenames(); + // Apply symbol renames for -wrap. + Symtab->applySymbolWrap(); // Now that we have a complete list of input files. // Beyond this point, no new files are added. // Aggregate all input sections into one place. - for (elf::ObjectFile<ELFT> *F : Symtab.getObjectFiles()) + for (InputFile *F : ObjectFiles) for (InputSectionBase *S : F->getSections()) if (S && S != &InputSection::Discarded) InputSections.push_back(S); - for (BinaryFile *F : Symtab.getBinaryFiles()) + for (BinaryFile *F : BinaryFiles) for (InputSectionBase *S : F->getSections()) InputSections.push_back(cast<InputSection>(S)); + // We do not want to emit debug sections if --strip-all + // or -strip-debug are given. + if (Config->Strip != StripPolicy::None) + llvm::erase_if(InputSections, [](InputSectionBase *S) { + return S->Name.startswith(".debug") || S->Name.startswith(".zdebug"); + }); + + Config->EFlags = Target->calcEFlags(); + + if (Config->EMachine == EM_ARM) { + // FIXME: These warnings can be removed when lld only uses these features + // when the input objects have been compiled with an architecture that + // supports them. + if (Config->ARMHasBlx == false) + warn("lld uses blx instruction, no object with architecture supporting " + "feature detected."); + if (Config->ARMJ1J2BranchEncoding == false) + warn("lld uses extended branch encoding, no object with architecture " + "supporting feature detected."); + if (Config->ARMHasMovtMovw == false) + warn("lld may use movt/movw, no object with architecture supporting " + "feature detected."); + } + // This adds a .comment section containing a version string. We have to add it // before decompressAndMergeSections because the .comment section is a // mergeable section. @@ -1050,9 +1115,9 @@ template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) { // Do size optimizations: garbage collection, merging of SHF_MERGE sections // and identical code folding. - if (Config->GcSections) - markLive<ELFT>(); - decompressAndMergeSections(); + markLive<ELFT>(); + decompressSections(); + mergeSections(); if (Config->ICF) doIcf<ELFT>(); |