diff options
| -rw-r--r-- | llvm/tools/llvm-objcopy/ELF/ELFObjcopy.cpp | 202 |
1 files changed, 106 insertions, 96 deletions
diff --git a/llvm/tools/llvm-objcopy/ELF/ELFObjcopy.cpp b/llvm/tools/llvm-objcopy/ELF/ELFObjcopy.cpp index fc1ac38ec87..1ae802ff14b 100644 --- a/llvm/tools/llvm-objcopy/ELF/ELFObjcopy.cpp +++ b/llvm/tools/llvm-objcopy/ELF/ELFObjcopy.cpp @@ -298,110 +298,94 @@ static bool isUnneededSymbol(const Symbol &Sym) { Sym.Type != STT_FILE && Sym.Type != STT_SECTION; } -// This function handles the high level operations of GNU objcopy including -// handling command line options. It's important to outline certain properties -// we expect to hold of the command line operations. Any operation that "keeps" -// should keep regardless of a remove. Additionally any removal should respect -// any previous removals. Lastly whether or not something is removed shouldn't -// depend a) on the order the options occur in or b) on some opaque priority -// system. The only priority is that keeps/copies overrule removes. -static Error handleArgs(const CopyConfig &Config, Object &Obj, - const Reader &Reader, ElfType OutputElfType) { - - if (!Config.SplitDWO.empty()) - if (Error E = - splitDWOToFile(Config, Reader, Config.SplitDWO, OutputElfType)) - return E; - - if (Config.OutputArch) { - Obj.Machine = Config.OutputArch.getValue().EMachine; - Obj.OSABI = Config.OutputArch.getValue().OSABI; - } - +static Error updateAndRemoveSymbols(const CopyConfig &Config, Object &Obj) { // TODO: update or remove symbols only if there is an option that affects // them. - if (Obj.SymbolTable) { - Obj.SymbolTable->updateSymbols([&](Symbol &Sym) { - // Common and undefined symbols don't make sense as local symbols, and can - // even cause crashes if we localize those, so skip them. - if (!Sym.isCommon() && Sym.getShndx() != SHN_UNDEF && - ((Config.LocalizeHidden && - (Sym.Visibility == STV_HIDDEN || Sym.Visibility == STV_INTERNAL)) || - is_contained(Config.SymbolsToLocalize, Sym.Name))) - Sym.Binding = STB_LOCAL; - - // Note: these two globalize flags have very similar names but different - // meanings: - // - // --globalize-symbol: promote a symbol to global - // --keep-global-symbol: all symbols except for these should be made local - // - // If --globalize-symbol is specified for a given symbol, it will be - // global in the output file even if it is not included via - // --keep-global-symbol. Because of that, make sure to check - // --globalize-symbol second. - if (!Config.SymbolsToKeepGlobal.empty() && - !is_contained(Config.SymbolsToKeepGlobal, Sym.Name) && - Sym.getShndx() != SHN_UNDEF) - Sym.Binding = STB_LOCAL; - - if (is_contained(Config.SymbolsToGlobalize, Sym.Name) && - Sym.getShndx() != SHN_UNDEF) - Sym.Binding = STB_GLOBAL; - - if (is_contained(Config.SymbolsToWeaken, Sym.Name) && - Sym.Binding == STB_GLOBAL) - Sym.Binding = STB_WEAK; - - if (Config.Weaken && Sym.Binding == STB_GLOBAL && - Sym.getShndx() != SHN_UNDEF) - Sym.Binding = STB_WEAK; - - const auto I = Config.SymbolsToRename.find(Sym.Name); - if (I != Config.SymbolsToRename.end()) - Sym.Name = I->getValue(); - - if (!Config.SymbolsPrefix.empty() && Sym.Type != STT_SECTION) - Sym.Name = (Config.SymbolsPrefix + Sym.Name).str(); - }); - - // The purpose of this loop is to mark symbols referenced by sections - // (like GroupSection or RelocationSection). This way, we know which - // symbols are still 'needed' and which are not. - if (Config.StripUnneeded || !Config.UnneededSymbolsToRemove.empty()) { - for (auto &Section : Obj.sections()) - Section.markSymbols(); - } + if (!Obj.SymbolTable) + return Error::success(); + + Obj.SymbolTable->updateSymbols([&](Symbol &Sym) { + // Common and undefined symbols don't make sense as local symbols, and can + // even cause crashes if we localize those, so skip them. + if (!Sym.isCommon() && Sym.getShndx() != SHN_UNDEF && + ((Config.LocalizeHidden && + (Sym.Visibility == STV_HIDDEN || Sym.Visibility == STV_INTERNAL)) || + is_contained(Config.SymbolsToLocalize, Sym.Name))) + Sym.Binding = STB_LOCAL; + + // Note: these two globalize flags have very similar names but different + // meanings: + // + // --globalize-symbol: promote a symbol to global + // --keep-global-symbol: all symbols except for these should be made local + // + // If --globalize-symbol is specified for a given symbol, it will be + // global in the output file even if it is not included via + // --keep-global-symbol. Because of that, make sure to check + // --globalize-symbol second. + if (!Config.SymbolsToKeepGlobal.empty() && + !is_contained(Config.SymbolsToKeepGlobal, Sym.Name) && + Sym.getShndx() != SHN_UNDEF) + Sym.Binding = STB_LOCAL; + + if (is_contained(Config.SymbolsToGlobalize, Sym.Name) && + Sym.getShndx() != SHN_UNDEF) + Sym.Binding = STB_GLOBAL; + + if (is_contained(Config.SymbolsToWeaken, Sym.Name) && + Sym.Binding == STB_GLOBAL) + Sym.Binding = STB_WEAK; + + if (Config.Weaken && Sym.Binding == STB_GLOBAL && + Sym.getShndx() != SHN_UNDEF) + Sym.Binding = STB_WEAK; + + const auto I = Config.SymbolsToRename.find(Sym.Name); + if (I != Config.SymbolsToRename.end()) + Sym.Name = I->getValue(); + + if (!Config.SymbolsPrefix.empty() && Sym.Type != STT_SECTION) + Sym.Name = (Config.SymbolsPrefix + Sym.Name).str(); + }); + + // The purpose of this loop is to mark symbols referenced by sections + // (like GroupSection or RelocationSection). This way, we know which + // symbols are still 'needed' and which are not. + if (Config.StripUnneeded || !Config.UnneededSymbolsToRemove.empty()) { + for (auto &Section : Obj.sections()) + Section.markSymbols(); + } - auto RemoveSymbolsPred = [&](const Symbol &Sym) { - if (is_contained(Config.SymbolsToKeep, Sym.Name) || - (Config.KeepFileSymbols && Sym.Type == STT_FILE)) - return false; + auto RemoveSymbolsPred = [&](const Symbol &Sym) { + if (is_contained(Config.SymbolsToKeep, Sym.Name) || + (Config.KeepFileSymbols && Sym.Type == STT_FILE)) + return false; - if ((Config.DiscardMode == DiscardType::All || - (Config.DiscardMode == DiscardType::Locals && - StringRef(Sym.Name).startswith(".L"))) && - Sym.Binding == STB_LOCAL && Sym.getShndx() != SHN_UNDEF && - Sym.Type != STT_FILE && Sym.Type != STT_SECTION) - return true; + if ((Config.DiscardMode == DiscardType::All || + (Config.DiscardMode == DiscardType::Locals && + StringRef(Sym.Name).startswith(".L"))) && + Sym.Binding == STB_LOCAL && Sym.getShndx() != SHN_UNDEF && + Sym.Type != STT_FILE && Sym.Type != STT_SECTION) + return true; - if (Config.StripAll || Config.StripAllGNU) - return true; + if (Config.StripAll || Config.StripAllGNU) + return true; - if (is_contained(Config.SymbolsToRemove, Sym.Name)) - return true; + if (is_contained(Config.SymbolsToRemove, Sym.Name)) + return true; - if ((Config.StripUnneeded || - is_contained(Config.UnneededSymbolsToRemove, Sym.Name)) && - isUnneededSymbol(Sym)) - return true; + if ((Config.StripUnneeded || + is_contained(Config.UnneededSymbolsToRemove, Sym.Name)) && + isUnneededSymbol(Sym)) + return true; - return false; - }; - if (Error E = Obj.removeSymbols(RemoveSymbolsPred)) - return E; - } + return false; + }; + + return Obj.removeSymbols(RemoveSymbolsPred); +} +static Error replaceAndRemoveSections(const CopyConfig &Config, Object &Obj) { SectionPred RemovePred = [](const SectionBase &) { return false; }; // Removes: @@ -535,7 +519,33 @@ static Error handleArgs(const CopyConfig &Config, Object &Obj, return &Obj.addSection<DecompressedSection>(*CS); }); - if (Error E = Obj.removeSections(RemovePred)) + return Obj.removeSections(RemovePred); +} + +// This function handles the high level operations of GNU objcopy including +// handling command line options. It's important to outline certain properties +// we expect to hold of the command line operations. Any operation that "keeps" +// should keep regardless of a remove. Additionally any removal should respect +// any previous removals. Lastly whether or not something is removed shouldn't +// depend a) on the order the options occur in or b) on some opaque priority +// system. The only priority is that keeps/copies overrule removes. +static Error handleArgs(const CopyConfig &Config, Object &Obj, + const Reader &Reader, ElfType OutputElfType) { + + if (!Config.SplitDWO.empty()) + if (Error E = + splitDWOToFile(Config, Reader, Config.SplitDWO, OutputElfType)) + return E; + + if (Config.OutputArch) { + Obj.Machine = Config.OutputArch.getValue().EMachine; + Obj.OSABI = Config.OutputArch.getValue().OSABI; + } + + if (Error E = updateAndRemoveSymbols(Config, Obj)) + return E; + + if (Error E = replaceAndRemoveSections(Config, Obj)) return E; if (!Config.SectionsToRename.empty()) { |
