[llvm-objcopy] Move elf-specific code into subfolder
In this diff the elf-specific code is moved into the subfolder ELF
(and factored out from llvm-objcopy.cpp).
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D53790
llvm-svn: 345544
diff --git a/llvm/tools/llvm-objcopy/llvm-objcopy.cpp b/llvm/tools/llvm-objcopy/llvm-objcopy.cpp
index b7e2361..deaea5e 100644
--- a/llvm/tools/llvm-objcopy/llvm-objcopy.cpp
+++ b/llvm/tools/llvm-objcopy/llvm-objcopy.cpp
@@ -10,16 +10,12 @@
#include "llvm-objcopy.h"
#include "Buffer.h"
#include "CopyConfig.h"
-#include "Object.h"
+#include "ELF/ELFObjcopy.h"
-#include "llvm/ADT/BitmaskEnum.h"
-#include "llvm/ADT/Optional.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
-#include "llvm/BinaryFormat/ELF.h"
-#include "llvm/MC/MCTargetOptions.h"
#include "llvm/Object/Archive.h"
#include "llvm/Object/ArchiveWriter.h"
#include "llvm/Object/Binary.h"
@@ -30,13 +26,9 @@
#include "llvm/Option/ArgList.h"
#include "llvm/Option/Option.h"
#include "llvm/Support/Casting.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/Support/Compression.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ErrorOr.h"
-#include "llvm/Support/FileOutputBuffer.h"
#include "llvm/Support/InitLLVM.h"
#include "llvm/Support/Memory.h"
#include "llvm/Support/Path.h"
@@ -46,8 +38,6 @@
#include <algorithm>
#include <cassert>
#include <cstdlib>
-#include <functional>
-#include <iterator>
#include <memory>
#include <string>
#include <system_error>
@@ -85,466 +75,6 @@
} // end namespace objcopy
} // end namespace llvm
-// TODO: move everything enclosed in the namespace llvm::objcopy::elf
-// into separate header+cpp files.
-namespace llvm {
-namespace objcopy {
-namespace elf {
-
-using namespace object;
-using namespace ELF;
-using SectionPred = std::function<bool(const SectionBase &Sec)>;
-
-static bool isDebugSection(const SectionBase &Sec) {
- return StringRef(Sec.Name).startswith(".debug") ||
- StringRef(Sec.Name).startswith(".zdebug") || Sec.Name == ".gdb_index";
-}
-
-static bool isDWOSection(const SectionBase &Sec) {
- return StringRef(Sec.Name).endswith(".dwo");
-}
-
-static bool onlyKeepDWOPred(const Object &Obj, const SectionBase &Sec) {
- // We can't remove the section header string table.
- if (&Sec == Obj.SectionNames)
- return false;
- // Short of keeping the string table we want to keep everything that is a DWO
- // section and remove everything else.
- return !isDWOSection(Sec);
-}
-
-static ElfType getOutputElfType(const Binary &Bin) {
- // Infer output ELF type from the input ELF object
- if (isa<ELFObjectFile<ELF32LE>>(Bin))
- return ELFT_ELF32LE;
- if (isa<ELFObjectFile<ELF64LE>>(Bin))
- return ELFT_ELF64LE;
- if (isa<ELFObjectFile<ELF32BE>>(Bin))
- return ELFT_ELF32BE;
- if (isa<ELFObjectFile<ELF64BE>>(Bin))
- return ELFT_ELF64BE;
- llvm_unreachable("Invalid ELFType");
-}
-
-static ElfType getOutputElfType(const MachineInfo &MI) {
- // Infer output ELF type from the binary arch specified
- if (MI.Is64Bit)
- return MI.IsLittleEndian ? ELFT_ELF64LE : ELFT_ELF64BE;
- else
- return MI.IsLittleEndian ? ELFT_ELF32LE : ELFT_ELF32BE;
-}
-
-static std::unique_ptr<Writer> createWriter(const CopyConfig &Config,
- Object &Obj, Buffer &Buf,
- ElfType OutputElfType) {
- if (Config.OutputFormat == "binary") {
- return llvm::make_unique<BinaryWriter>(Obj, Buf);
- }
- // Depending on the initial ELFT and OutputFormat we need a different Writer.
- switch (OutputElfType) {
- case ELFT_ELF32LE:
- return llvm::make_unique<ELFWriter<ELF32LE>>(Obj, Buf,
- !Config.StripSections);
- case ELFT_ELF64LE:
- return llvm::make_unique<ELFWriter<ELF64LE>>(Obj, Buf,
- !Config.StripSections);
- case ELFT_ELF32BE:
- return llvm::make_unique<ELFWriter<ELF32BE>>(Obj, Buf,
- !Config.StripSections);
- case ELFT_ELF64BE:
- return llvm::make_unique<ELFWriter<ELF64BE>>(Obj, Buf,
- !Config.StripSections);
- }
- llvm_unreachable("Invalid output format");
-}
-
-static void splitDWOToFile(const CopyConfig &Config, const Reader &Reader,
- StringRef File, ElfType OutputElfType) {
- auto DWOFile = Reader.create();
- DWOFile->removeSections(
- [&](const SectionBase &Sec) { return onlyKeepDWOPred(*DWOFile, Sec); });
- FileBuffer FB(File);
- auto Writer = createWriter(Config, *DWOFile, FB, OutputElfType);
- Writer->finalize();
- Writer->write();
-}
-
-static Error dumpSectionToFile(StringRef SecName, StringRef Filename,
- Object &Obj) {
- for (auto &Sec : Obj.sections()) {
- if (Sec.Name == SecName) {
- if (Sec.OriginalData.size() == 0)
- return make_error<StringError>("Can't dump section \"" + SecName +
- "\": it has no contents",
- object_error::parse_failed);
- Expected<std::unique_ptr<FileOutputBuffer>> BufferOrErr =
- FileOutputBuffer::create(Filename, Sec.OriginalData.size());
- if (!BufferOrErr)
- return BufferOrErr.takeError();
- std::unique_ptr<FileOutputBuffer> Buf = std::move(*BufferOrErr);
- std::copy(Sec.OriginalData.begin(), Sec.OriginalData.end(),
- Buf->getBufferStart());
- if (Error E = Buf->commit())
- return E;
- return Error::success();
- }
- }
- return make_error<StringError>("Section not found",
- object_error::parse_failed);
-}
-
-static bool isCompressed(const SectionBase &Section) {
- const char *Magic = "ZLIB";
- return StringRef(Section.Name).startswith(".zdebug") ||
- (Section.OriginalData.size() > strlen(Magic) &&
- !strncmp(reinterpret_cast<const char *>(Section.OriginalData.data()),
- Magic, strlen(Magic))) ||
- (Section.Flags & ELF::SHF_COMPRESSED);
-}
-
-static bool isCompressable(const SectionBase &Section) {
- return !isCompressed(Section) && isDebugSection(Section) &&
- Section.Name != ".gdb_index";
-}
-
-static void replaceDebugSections(
- const CopyConfig &Config, Object &Obj, SectionPred &RemovePred,
- function_ref<bool(const SectionBase &)> shouldReplace,
- function_ref<SectionBase *(const SectionBase *)> addSection) {
- SmallVector<SectionBase *, 13> ToReplace;
- SmallVector<RelocationSection *, 13> RelocationSections;
- for (auto &Sec : Obj.sections()) {
- if (RelocationSection *R = dyn_cast<RelocationSection>(&Sec)) {
- if (shouldReplace(*R->getSection()))
- RelocationSections.push_back(R);
- continue;
- }
-
- if (shouldReplace(Sec))
- ToReplace.push_back(&Sec);
- }
-
- for (SectionBase *S : ToReplace) {
- SectionBase *NewSection = addSection(S);
-
- for (RelocationSection *RS : RelocationSections) {
- if (RS->getSection() == S)
- RS->setSection(NewSection);
- }
- }
-
- RemovePred = [shouldReplace, RemovePred](const SectionBase &Sec) {
- return shouldReplace(Sec) || RemovePred(Sec);
- };
-}
-
-// 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 void handleArgs(const CopyConfig &Config, Object &Obj,
- const Reader &Reader, ElfType OutputElfType) {
-
- if (!Config.SplitDWO.empty()) {
- splitDWOToFile(Config, Reader, Config.SplitDWO, OutputElfType);
- }
-
- // TODO: update or remove symbols only if there is an option that affects
- // them.
- if (Obj.SymbolTable) {
- Obj.SymbolTable->updateSymbols([&](Symbol &Sym) {
- if ((Config.LocalizeHidden &&
- (Sym.Visibility == STV_HIDDEN || Sym.Visibility == STV_INTERNAL)) ||
- (!Config.SymbolsToLocalize.empty() &&
- 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.Binding = STB_LOCAL;
-
- if (!Config.SymbolsToGlobalize.empty() &&
- is_contained(Config.SymbolsToGlobalize, Sym.Name))
- Sym.Binding = STB_GLOBAL;
-
- if (!Config.SymbolsToWeaken.empty() &&
- 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) {
- for (auto &Section : Obj.sections())
- Section.markSymbols();
- }
-
- Obj.removeSymbols([&](const Symbol &Sym) {
- if ((!Config.SymbolsToKeep.empty() &&
- is_contained(Config.SymbolsToKeep, Sym.Name)) ||
- (Config.KeepFileSymbols && Sym.Type == STT_FILE))
- return false;
-
- if (Config.DiscardAll && 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.SymbolsToRemove.empty() &&
- is_contained(Config.SymbolsToRemove, Sym.Name)) {
- return true;
- }
-
- if (Config.StripUnneeded && !Sym.Referenced &&
- (Sym.Binding == STB_LOCAL || Sym.getShndx() == SHN_UNDEF) &&
- Sym.Type != STT_FILE && Sym.Type != STT_SECTION)
- return true;
-
- return false;
- });
- }
-
- SectionPred RemovePred = [](const SectionBase &) { return false; };
-
- // Removes:
- if (!Config.ToRemove.empty()) {
- RemovePred = [&Config](const SectionBase &Sec) {
- return is_contained(Config.ToRemove, Sec.Name);
- };
- }
-
- if (Config.StripDWO || !Config.SplitDWO.empty())
- RemovePred = [RemovePred](const SectionBase &Sec) {
- return isDWOSection(Sec) || RemovePred(Sec);
- };
-
- if (Config.ExtractDWO)
- RemovePred = [RemovePred, &Obj](const SectionBase &Sec) {
- return onlyKeepDWOPred(Obj, Sec) || RemovePred(Sec);
- };
-
- if (Config.StripAllGNU)
- RemovePred = [RemovePred, &Obj](const SectionBase &Sec) {
- if (RemovePred(Sec))
- return true;
- if ((Sec.Flags & SHF_ALLOC) != 0)
- return false;
- if (&Sec == Obj.SectionNames)
- return false;
- switch (Sec.Type) {
- case SHT_SYMTAB:
- case SHT_REL:
- case SHT_RELA:
- case SHT_STRTAB:
- return true;
- }
- return isDebugSection(Sec);
- };
-
- if (Config.StripSections) {
- RemovePred = [RemovePred](const SectionBase &Sec) {
- return RemovePred(Sec) || (Sec.Flags & SHF_ALLOC) == 0;
- };
- }
-
- if (Config.StripDebug) {
- RemovePred = [RemovePred](const SectionBase &Sec) {
- return RemovePred(Sec) || isDebugSection(Sec);
- };
- }
-
- if (Config.StripNonAlloc)
- RemovePred = [RemovePred, &Obj](const SectionBase &Sec) {
- if (RemovePred(Sec))
- return true;
- if (&Sec == Obj.SectionNames)
- return false;
- return (Sec.Flags & SHF_ALLOC) == 0;
- };
-
- if (Config.StripAll)
- RemovePred = [RemovePred, &Obj](const SectionBase &Sec) {
- if (RemovePred(Sec))
- return true;
- if (&Sec == Obj.SectionNames)
- return false;
- if (StringRef(Sec.Name).startswith(".gnu.warning"))
- return false;
- return (Sec.Flags & SHF_ALLOC) == 0;
- };
-
- // Explicit copies:
- if (!Config.OnlyKeep.empty()) {
- RemovePred = [&Config, RemovePred, &Obj](const SectionBase &Sec) {
- // Explicitly keep these sections regardless of previous removes.
- if (is_contained(Config.OnlyKeep, Sec.Name))
- return false;
-
- // Allow all implicit removes.
- if (RemovePred(Sec))
- return true;
-
- // Keep special sections.
- if (Obj.SectionNames == &Sec)
- return false;
- if (Obj.SymbolTable == &Sec ||
- (Obj.SymbolTable && Obj.SymbolTable->getStrTab() == &Sec))
- return false;
-
- // Remove everything else.
- return true;
- };
- }
-
- if (!Config.Keep.empty()) {
- RemovePred = [Config, RemovePred](const SectionBase &Sec) {
- // Explicitly keep these sections regardless of previous removes.
- if (is_contained(Config.Keep, Sec.Name))
- return false;
- // Otherwise defer to RemovePred.
- return RemovePred(Sec);
- };
- }
-
- // This has to be the last predicate assignment.
- // If the option --keep-symbol has been specified
- // and at least one of those symbols is present
- // (equivalently, the updated symbol table is not empty)
- // the symbol table and the string table should not be removed.
- if ((!Config.SymbolsToKeep.empty() || Config.KeepFileSymbols) &&
- Obj.SymbolTable && !Obj.SymbolTable->empty()) {
- RemovePred = [&Obj, RemovePred](const SectionBase &Sec) {
- if (&Sec == Obj.SymbolTable || &Sec == Obj.SymbolTable->getStrTab())
- return false;
- return RemovePred(Sec);
- };
- }
-
- if (Config.CompressionType != DebugCompressionType::None)
- replaceDebugSections(Config, Obj, RemovePred, isCompressable,
- [&Config, &Obj](const SectionBase *S) {
- return &Obj.addSection<CompressedSection>(
- *S, Config.CompressionType);
- });
- else if (Config.DecompressDebugSections)
- replaceDebugSections(
- Config, Obj, RemovePred,
- [](const SectionBase &S) { return isa<CompressedSection>(&S); },
- [&Obj](const SectionBase *S) {
- auto CS = cast<CompressedSection>(S);
- return &Obj.addSection<DecompressedSection>(*CS);
- });
-
- Obj.removeSections(RemovePred);
-
- if (!Config.SectionsToRename.empty()) {
- for (auto &Sec : Obj.sections()) {
- const auto Iter = Config.SectionsToRename.find(Sec.Name);
- if (Iter != Config.SectionsToRename.end()) {
- const SectionRename &SR = Iter->second;
- Sec.Name = SR.NewName;
- if (SR.NewFlags.hasValue()) {
- // Preserve some flags which should not be dropped when setting flags.
- // Also, preserve anything OS/processor dependant.
- const uint64_t PreserveMask = ELF::SHF_COMPRESSED | ELF::SHF_EXCLUDE |
- ELF::SHF_GROUP | ELF::SHF_LINK_ORDER |
- ELF::SHF_MASKOS | ELF::SHF_MASKPROC |
- ELF::SHF_TLS | ELF::SHF_INFO_LINK;
- Sec.Flags = (Sec.Flags & PreserveMask) |
- (SR.NewFlags.getValue() & ~PreserveMask);
- }
- }
- }
- }
-
- if (!Config.AddSection.empty()) {
- for (const auto &Flag : Config.AddSection) {
- auto SecPair = Flag.split("=");
- auto SecName = SecPair.first;
- auto File = SecPair.second;
- auto BufOrErr = MemoryBuffer::getFile(File);
- if (!BufOrErr)
- reportError(File, BufOrErr.getError());
- auto Buf = std::move(*BufOrErr);
- auto BufPtr = reinterpret_cast<const uint8_t *>(Buf->getBufferStart());
- auto BufSize = Buf->getBufferSize();
- Obj.addSection<OwnedDataSection>(SecName,
- ArrayRef<uint8_t>(BufPtr, BufSize));
- }
- }
-
- if (!Config.DumpSection.empty()) {
- for (const auto &Flag : Config.DumpSection) {
- std::pair<StringRef, StringRef> SecPair = Flag.split("=");
- StringRef SecName = SecPair.first;
- StringRef File = SecPair.second;
- if (Error E = dumpSectionToFile(SecName, File, Obj))
- reportError(Config.InputFilename, std::move(E));
- }
- }
-
- if (!Config.AddGnuDebugLink.empty())
- Obj.addSection<GnuDebugLinkSection>(Config.AddGnuDebugLink);
-}
-
-void executeObjcopyOnRawBinary(const CopyConfig &Config, MemoryBuffer &In,
- Buffer &Out) {
- BinaryReader Reader(Config.BinaryArch, &In);
- std::unique_ptr<Object> Obj = Reader.create();
-
- const ElfType OutputElfType = getOutputElfType(Config.BinaryArch);
- handleArgs(Config, *Obj, Reader, OutputElfType);
- std::unique_ptr<Writer> Writer =
- createWriter(Config, *Obj, Out, OutputElfType);
- Writer->finalize();
- Writer->write();
-}
-
-void executeObjcopyOnBinary(const CopyConfig &Config,
- object::ELFObjectFileBase &In, Buffer &Out) {
- ELFReader Reader(&In);
- std::unique_ptr<Object> Obj = Reader.create();
- const ElfType OutputElfType = getOutputElfType(In);
- handleArgs(Config, *Obj, Reader, OutputElfType);
- std::unique_ptr<Writer> Writer =
- createWriter(Config, *Obj, Out, OutputElfType);
- Writer->finalize();
- Writer->write();
-}
-
-} // end namespace elf
-} // end namespace objcopy
-} // end namespace llvm
-
using namespace llvm;
using namespace llvm::object;
using namespace llvm::objcopy;