[llvm] r361466 - [llvm-objcopy] - Many minor NFC changes to cleanup/improve the code in ELF/Object.cpp.
George Rimar via llvm-commits
llvm-commits at lists.llvm.org
Thu May 23 02:18:57 PDT 2019
Author: grimar
Date: Thu May 23 02:18:57 2019
New Revision: 361466
URL: http://llvm.org/viewvc/llvm-project?rev=361466&view=rev
Log:
[llvm-objcopy] - Many minor NFC changes to cleanup/improve the code in ELF/Object.cpp.
The code in ELF/Object.cpp is sometimes a bit hard to read because of
lots of auto used everywhere. The main intention of this patch is
to replace them with the real type for places where it is not obvious.
Also it cleanups few places.
It is NFC change, but I want to be sure that there is no objections to do that since it
is massive.
DIfferential revision: https://reviews.llvm.org/D62260
Modified:
llvm/trunk/tools/llvm-objcopy/ELF/Object.cpp
Modified: llvm/trunk/tools/llvm-objcopy/ELF/Object.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objcopy/ELF/Object.cpp?rev=361466&r1=361465&r2=361466&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/ELF/Object.cpp (original)
+++ llvm/trunk/tools/llvm-objcopy/ELF/Object.cpp Thu May 23 02:18:57 2019
@@ -37,8 +37,8 @@ using namespace object;
using namespace ELF;
template <class ELFT> void ELFWriter<ELFT>::writePhdr(const Segment &Seg) {
- uint8_t *B = Buf.getBufferStart();
- B += Obj.ProgramHdrSegment.Offset + Seg.Index * sizeof(Elf_Phdr);
+ uint8_t *B = Buf.getBufferStart() + Obj.ProgramHdrSegment.Offset +
+ Seg.Index * sizeof(Elf_Phdr);
Elf_Phdr &Phdr = *reinterpret_cast<Elf_Phdr *>(B);
Phdr.p_type = Seg.Type;
Phdr.p_flags = Seg.Flags;
@@ -67,8 +67,7 @@ void SectionBase::replaceSectionReferenc
const DenseMap<SectionBase *, SectionBase *> &) {}
template <class ELFT> void ELFWriter<ELFT>::writeShdr(const SectionBase &Sec) {
- uint8_t *B = Buf.getBufferStart();
- B += Sec.HeaderOffset;
+ uint8_t *B = Buf.getBufferStart() + Sec.HeaderOffset;
Elf_Shdr &Shdr = *reinterpret_cast<Elf_Shdr *>(B);
Shdr.sh_name = Sec.NameIndex;
Shdr.sh_type = Sec.Type;
@@ -144,10 +143,8 @@ void BinarySectionWriter::visit(const Gr
}
void SectionWriter::visit(const Section &Sec) {
- if (Sec.Type == SHT_NOBITS)
- return;
- uint8_t *Buf = Out.getBufferStart() + Sec.Offset;
- llvm::copy(Sec.Contents, Buf);
+ if (Sec.Type != SHT_NOBITS)
+ llvm::copy(Sec.Contents, Out.getBufferStart() + Sec.Offset);
}
void Section::accept(SectionVisitor &Visitor) const { Visitor.visit(*this); }
@@ -155,8 +152,7 @@ void Section::accept(SectionVisitor &Vis
void Section::accept(MutableSectionVisitor &Visitor) { Visitor.visit(*this); }
void SectionWriter::visit(const OwnedDataSection &Sec) {
- uint8_t *Buf = Out.getBufferStart() + Sec.Offset;
- llvm::copy(Sec.Data, Buf);
+ llvm::copy(Sec.Data, Out.getBufferStart() + Sec.Offset);
}
static const std::vector<uint8_t> ZlibGnuMagic = {'Z', 'L', 'I', 'B'};
@@ -227,9 +223,7 @@ void BinarySectionWriter::visit(const Co
template <class ELFT>
void ELFSectionWriter<ELFT>::visit(const CompressedSection &Sec) {
- uint8_t *Buf = Out.getBufferStart();
- Buf += Sec.Offset;
-
+ uint8_t *Buf = Out.getBufferStart() + Sec.Offset;
if (Sec.CompressionType == DebugCompressionType::None) {
std::copy(Sec.OriginalData.begin(), Sec.OriginalData.end(), Buf);
return;
@@ -323,8 +317,7 @@ void StringTableSection::accept(MutableS
template <class ELFT>
void ELFSectionWriter<ELFT>::visit(const SectionIndexSection &Sec) {
uint8_t *Buf = Out.getBufferStart() + Sec.Offset;
- auto *IndexesBuffer = reinterpret_cast<Elf_Word *>(Buf);
- llvm::copy(Sec.Indexes, IndexesBuffer);
+ llvm::copy(Sec.Indexes, reinterpret_cast<Elf_Word *>(Buf));
}
void SectionIndexSection::initialize(SectionTableRef SecTable) {
@@ -481,7 +474,7 @@ void SymbolTableSection::initialize(Sect
void SymbolTableSection::finalize() {
uint32_t MaxLocalIndex = 0;
- for (auto &Sym : Symbols) {
+ for (std::unique_ptr<Symbol> &Sym : Symbols) {
Sym->NameIndex =
SymbolNames == nullptr ? 0 : SymbolNames->findIndex(Sym->Name);
if (Sym->Binding == STB_LOCAL)
@@ -504,7 +497,7 @@ void SymbolTableSection::prepareForLayou
// If the symbol names section has been removed, don't try to add strings to
// the table.
if (SymbolNames != nullptr)
- for (auto &Sym : Symbols)
+ for (std::unique_ptr<Symbol> &Sym : Symbols)
SymbolNames->addString(Sym->Name);
}
@@ -513,7 +506,7 @@ void SymbolTableSection::fillShndxTable(
return;
// Fill section index table with real section indexes. This function must
// be called after assignOffsets.
- for (const auto &Sym : Symbols) {
+ for (const std::unique_ptr<Symbol> &Sym : Symbols) {
if (Sym->DefinedIn != nullptr && Sym->DefinedIn->Index >= SHN_LORESERVE)
SectionIndexTable->addIndex(Sym->DefinedIn->Index);
else
@@ -534,11 +527,9 @@ Symbol *SymbolTableSection::getSymbolByI
template <class ELFT>
void ELFSectionWriter<ELFT>::visit(const SymbolTableSection &Sec) {
- uint8_t *Buf = Out.getBufferStart();
- Buf += Sec.Offset;
- Elf_Sym *Sym = reinterpret_cast<Elf_Sym *>(Buf);
+ Elf_Sym *Sym = reinterpret_cast<Elf_Sym *>(Out.getBufferStart() + Sec.Offset);
// Loop though symbols setting each entry of the symbol table.
- for (auto &Symbol : Sec.Symbols) {
+ for (const std::unique_ptr<Symbol> &Symbol : Sec.Symbols) {
Sym->st_name = Symbol->NameIndex;
Sym->st_value = Symbol->Value;
Sym->st_size = Symbol->Size;
@@ -671,8 +662,7 @@ void RelocationSection::replaceSectionRe
}
void SectionWriter::visit(const DynamicRelocationSection &Sec) {
- llvm::copy(Sec.Contents,
- Out.getBufferStart() + Sec.Offset);
+ llvm::copy(Sec.Contents, Out.getBufferStart() + Sec.Offset);
}
void DynamicRelocationSection::accept(SectionVisitor &Visitor) const {
@@ -680,33 +670,32 @@ void DynamicRelocationSection::accept(Se
}
void DynamicRelocationSection::accept(MutableSectionVisitor &Visitor) {
- Visitor.visit(*this);
-}
-
-Error DynamicRelocationSection::removeSectionReferences(
- bool AllowBrokenLinks, function_ref<bool(const SectionBase *)> ToRemove) {
- if (ToRemove(Symbols)) {
- if (!AllowBrokenLinks)
- return createStringError(
- llvm::errc::invalid_argument,
+ Visitor.visit(*this);
+}
+
+Error DynamicRelocationSection::removeSectionReferences(
+ bool AllowBrokenLinks, function_ref<bool(const SectionBase *)> ToRemove) {
+ if (ToRemove(Symbols)) {
+ if (!AllowBrokenLinks)
+ return createStringError(
+ llvm::errc::invalid_argument,
"symbol table '%s' cannot be removed because it is "
"referenced by the relocation section '%s'",
- Symbols->Name.data(), this->Name.data());
- Symbols = nullptr;
- }
-
- // SecToApplyRel contains a section referenced by sh_info field. It keeps
- // a section to which the relocation section applies. When we remove any
- // sections we also remove their relocation sections. Since we do that much
- // earlier, this assert should never be triggered.
- assert(!SecToApplyRel || !ToRemove(SecToApplyRel));
-
- return Error::success();
-}
-
-Error Section::removeSectionReferences(bool AllowBrokenDependency,
- function_ref<bool(const SectionBase *)> ToRemove) {
- if (ToRemove(LinkSection)) {
+ Symbols->Name.data(), this->Name.data());
+ Symbols = nullptr;
+ }
+
+ // SecToApplyRel contains a section referenced by sh_info field. It keeps
+ // a section to which the relocation section applies. When we remove any
+ // sections we also remove their relocation sections. Since we do that much
+ // earlier, this assert should never be triggered.
+ assert(!SecToApplyRel || !ToRemove(SecToApplyRel));
+ return Error::success();
+}
+
+Error Section::removeSectionReferences(bool AllowBrokenDependency,
+ function_ref<bool(const SectionBase *)> ToRemove) {
+ if (ToRemove(LinkSection)) {
if (!AllowBrokenDependency)
return createStringError(llvm::errc::invalid_argument,
"section '%s' cannot be removed because it is "
@@ -744,13 +733,13 @@ void GroupSection::replaceSectionReferen
}
void Section::initialize(SectionTableRef SecTable) {
- if (Link != ELF::SHN_UNDEF) {
- LinkSection =
- SecTable.getSection(Link, "Link field value " + Twine(Link) +
- " in section " + Name + " is invalid");
- if (LinkSection->Type == ELF::SHT_SYMTAB)
- LinkSection = nullptr;
- }
+ if (Link == ELF::SHN_UNDEF)
+ return;
+ LinkSection =
+ SecTable.getSection(Link, "Link field value " + Twine(Link) +
+ " in section " + Name + " is invalid");
+ if (LinkSection->Type == ELF::SHT_SYMTAB)
+ LinkSection = nullptr;
}
void Section::finalize() { this->Link = LinkSection ? LinkSection->Index : 0; }
@@ -800,7 +789,7 @@ void ELFSectionWriter<ELFT>::visit(const
ELF::Elf32_Word *Buf =
reinterpret_cast<ELF::Elf32_Word *>(Out.getBufferStart() + Sec.Offset);
*Buf++ = Sec.FlagWord;
- for (const auto *S : Sec.GroupMembers)
+ for (SectionBase *S : Sec.GroupMembers)
support::endian::write32<ELFT::TargetEndianness>(Buf++, S->Index);
}
@@ -908,16 +897,15 @@ void BinaryELFBuilder::addData(SymbolTab
}
void BinaryELFBuilder::initSections() {
- for (auto &Section : Obj->sections()) {
+ for (SectionBase &Section : Obj->sections())
Section.initialize(Obj->sections());
- }
}
std::unique_ptr<Object> BinaryELFBuilder::build() {
initFileHeader();
initHeaderSegment();
- StringTableSection *StrTab = addStrTab();
- SymbolTableSection *SymTab = addSymTab(StrTab);
+
+ SymbolTableSection *SymTab = addSymTab(addStrTab());
initSections();
addData(SymTab);
@@ -925,7 +913,7 @@ std::unique_ptr<Object> BinaryELFBuilder
}
template <class ELFT> void ELFBuilder<ELFT>::setParentSegment(Segment &Child) {
- for (auto &Parent : Obj.segments()) {
+ for (Segment &Parent : Obj.segments()) {
// Every segment will overlap with itself but we don't want a segment to
// be it's own parent so we avoid that situation.
if (&Child != &Parent && segmentOverlapsSegment(Child, Parent)) {
@@ -956,7 +944,7 @@ template <class ELFT> void ELFBuilder<EL
Seg.MemSize = Phdr.p_memsz;
Seg.Align = Phdr.p_align;
Seg.Index = Index++;
- for (auto &Section : Obj.sections()) {
+ for (SectionBase &Section : Obj.sections()) {
if (sectionWithinSegment(Section, Seg)) {
Seg.addSection(&Section);
if (!Section.ParentSegment ||
@@ -987,7 +975,7 @@ template <class ELFT> void ELFBuilder<EL
// Now we do an O(n^2) loop through the segments in order to match up
// segments.
- for (auto &Child : Obj.segments())
+ for (Segment &Child : Obj.segments())
setParentSegment(Child);
setParentSegment(ElfHdr);
setParentSegment(PrHdr);
@@ -998,14 +986,14 @@ void ELFBuilder<ELFT>::initGroupSection(
if (GroupSec->Align % sizeof(ELF::Elf32_Word) != 0)
error("invalid alignment " + Twine(GroupSec->Align) + " of group section '" +
GroupSec->Name + "'");
- auto SecTable = Obj.sections();
+ SectionTableRef SecTable = Obj.sections();
auto SymTab = SecTable.template getSectionOfType<SymbolTableSection>(
GroupSec->Link,
"link field value '" + Twine(GroupSec->Link) + "' in section '" +
GroupSec->Name + "' is invalid",
"link field value '" + Twine(GroupSec->Link) + "' in section '" +
GroupSec->Name + "' is not a symbol table");
- auto Sym = SymTab->getSymbolByIndex(GroupSec->Info);
+ Symbol *Sym = SymTab->getSymbolByIndex(GroupSec->Info);
if (!Sym)
error("info field value '" + Twine(GroupSec->Info) + "' in section '" +
GroupSec->Name + "' is not a valid symbol index");
@@ -1294,8 +1282,7 @@ std::unique_ptr<Object> ELFReader::creat
}
template <class ELFT> void ELFWriter<ELFT>::writeEhdr() {
- uint8_t *B = Buf.getBufferStart();
- Elf_Ehdr &Ehdr = *reinterpret_cast<Elf_Ehdr *>(B);
+ Elf_Ehdr &Ehdr = *reinterpret_cast<Elf_Ehdr *>(Buf.getBufferStart());
std::fill(Ehdr.e_ident, Ehdr.e_ident + 16, 0);
Ehdr.e_ident[EI_MAG0] = 0x7f;
Ehdr.e_ident[EI_MAG1] = 'E';
@@ -1357,10 +1344,10 @@ template <class ELFT> void ELFWriter<ELF
}
template <class ELFT> void ELFWriter<ELFT>::writeShdrs() {
- uint8_t *B = Buf.getBufferStart() + Obj.SHOffset;
// This reference serves to write the dummy section header at the begining
// of the file. It is not used for anything else
- Elf_Shdr &Shdr = *reinterpret_cast<Elf_Shdr *>(B);
+ Elf_Shdr &Shdr =
+ *reinterpret_cast<Elf_Shdr *>(Buf.getBufferStart() + Obj.SHOffset);
Shdr.sh_name = 0;
Shdr.sh_type = SHT_NULL;
Shdr.sh_flags = 0;
@@ -1381,12 +1368,12 @@ template <class ELFT> void ELFWriter<ELF
Shdr.sh_addralign = 0;
Shdr.sh_entsize = 0;
- for (auto &Sec : Obj.sections())
+ for (SectionBase &Sec : Obj.sections())
writeShdr(Sec);
}
template <class ELFT> void ELFWriter<ELFT>::writeSectionData() {
- for (auto &Sec : Obj.sections())
+ for (SectionBase &Sec : Obj.sections())
// Segments are responsible for writing their contents, so only write the
// section data if the section is not in a segment. Note that this renders
// sections in segments effectively immutable.
@@ -1409,8 +1396,7 @@ template <class ELFT> void ELFWriter<ELF
continue;
uint64_t Offset =
Sec.OriginalOffset - Parent->OriginalOffset + Parent->Offset;
- uint8_t *B = Buf.getBufferStart();
- std::memset(B + Offset, 0, Sec.Size);
+ std::memset(Buf.getBufferStart() + Offset, 0, Sec.Size);
}
}
@@ -1515,20 +1501,20 @@ static uint64_t layoutSegments(std::vect
// then it's acceptable, but not ideal, to simply move it to after the
// segments. So we can simply layout segments one after the other accounting
// for alignment.
- for (auto &Segment : Segments) {
+ for (Segment *Seg : Segments) {
// We assume that segments have been ordered by OriginalOffset and Index
// such that a parent segment will always come before a child segment in
// OrderedSegments. This means that the Offset of the ParentSegment should
// already be set and we can set our offset relative to it.
- if (Segment->ParentSegment != nullptr) {
- auto Parent = Segment->ParentSegment;
- Segment->Offset =
- Parent->Offset + Segment->OriginalOffset - Parent->OriginalOffset;
+ if (Seg->ParentSegment != nullptr) {
+ Segment *Parent = Seg->ParentSegment;
+ Seg->Offset =
+ Parent->Offset + Seg->OriginalOffset - Parent->OriginalOffset;
} else {
- Offset = alignToAddr(Offset, Segment->VAddr, Segment->Align);
- Segment->Offset = Offset;
+ Offset = alignToAddr(Offset, Seg->VAddr, Seg->Align);
+ Seg->Offset = Offset;
}
- Offset = std::max(Offset, Segment->Offset + Segment->FileSize);
+ Offset = std::max(Offset, Seg->Offset + Seg->FileSize);
}
return Offset;
}
@@ -1565,7 +1551,7 @@ static uint64_t layoutSections(Range Sec
}
template <class ELFT> void ELFWriter<ELFT>::initEhdrSegment() {
- auto &ElfHdr = Obj.ElfHdrSegment;
+ Segment &ElfHdr = Obj.ElfHdrSegment;
ElfHdr.Type = PT_PHDR;
ElfHdr.Flags = 0;
ElfHdr.OriginalOffset = ElfHdr.Offset = 0;
@@ -1580,7 +1566,7 @@ template <class ELFT> void ELFWriter<ELF
// so that we know that anytime ->ParentSegment is set that segment has
// already had its offset properly set.
std::vector<Segment *> OrderedSegments;
- for (auto &Segment : Obj.segments())
+ for (Segment &Segment : Obj.segments())
OrderedSegments.push_back(&Segment);
OrderedSegments.push_back(&Obj.ElfHdrSegment);
OrderedSegments.push_back(&Obj.ProgramHdrSegment);
@@ -1635,7 +1621,7 @@ template <class ELFT> Error ELFWriter<EL
// we go to see if we will actully need large indexes.
bool NeedsLargeIndexes = false;
if (Obj.sections().size() >= SHN_LORESERVE) {
- auto Sections = Obj.sections();
+ SectionTableRef Sections = Obj.sections();
NeedsLargeIndexes =
std::any_of(Sections.begin() + SHN_LORESERVE, Sections.end(),
[](const SectionBase &Sec) { return Sec.HasSymbol; });
@@ -1693,7 +1679,7 @@ template <class ELFT> Error ELFWriter<EL
// Now that all strings are added we want to finalize string table builders,
// because that affects section sizes which in turn affects section offsets.
- for (auto &Sec : Obj.sections())
+ for (SectionBase &Sec : Obj.sections())
if (auto StrTab = dyn_cast<StringTableSection>(&Sec))
StrTab->prepareForLayout();
@@ -1707,7 +1693,7 @@ template <class ELFT> Error ELFWriter<EL
// Finally now that all offsets and indexes have been set we can finalize any
// remaining issues.
uint64_t Offset = Obj.SHOffset + sizeof(Elf_Shdr);
- for (auto &Section : Obj.sections()) {
+ for (SectionBase &Section : Obj.sections()) {
Section.HeaderOffset = Offset;
Offset += sizeof(Elf_Shdr);
if (WriteSectionHeaders)
@@ -1722,11 +1708,9 @@ template <class ELFT> Error ELFWriter<EL
}
Error BinaryWriter::write() {
- for (auto &Section : Obj.sections()) {
- if ((Section.Flags & SHF_ALLOC) == 0)
- continue;
- Section.accept(*SecWriter);
- }
+ for (auto &Section : Obj.sections())
+ if (Section.Flags & SHF_ALLOC)
+ Section.accept(*SecWriter);
return Buf.commit();
}
@@ -1739,11 +1723,9 @@ Error BinaryWriter::finalize() {
// already had it's offset properly set. We only want to consider the segments
// that will affect layout of allocated sections so we only add those.
std::vector<Segment *> OrderedSegments;
- for (auto &Section : Obj.sections()) {
- if ((Section.Flags & SHF_ALLOC) != 0 && Section.ParentSegment != nullptr) {
+ for (SectionBase &Section : Obj.sections())
+ if ((Section.Flags & SHF_ALLOC) != 0 && Section.ParentSegment != nullptr)
OrderedSegments.push_back(Section.ParentSegment);
- }
- }
// For binary output, we're going to use physical addresses instead of
// virtual addresses, since a binary output is used for cases like ROM
@@ -1770,8 +1752,8 @@ Error BinaryWriter::finalize() {
// our layout algorithm to proceed as expected while not writing out the gap
// at the start.
if (!OrderedSegments.empty()) {
- auto Seg = OrderedSegments[0];
- auto Sec = Seg->firstSection();
+ Segment *Seg = OrderedSegments[0];
+ const SectionBase *Sec = Seg->firstSection();
auto Diff = Sec->OriginalOffset - Seg->OriginalOffset;
Seg->OriginalOffset += Diff;
// The size needs to be shrunk as well.
@@ -1780,7 +1762,7 @@ Error BinaryWriter::finalize() {
// section.
Seg->PAddr += Diff;
uint64_t LowestPAddr = Seg->PAddr;
- for (auto &Segment : OrderedSegments) {
+ for (Segment *Segment : OrderedSegments) {
Segment->Offset = Segment->PAddr - LowestPAddr;
Offset = std::max(Offset, Segment->Offset + Segment->FileSize);
}
@@ -1791,11 +1773,9 @@ Error BinaryWriter::finalize() {
// not hold. Then pass such a range to LayoutSections instead of constructing
// AllocatedSections here.
std::vector<SectionBase *> AllocatedSections;
- for (auto &Section : Obj.sections()) {
- if ((Section.Flags & SHF_ALLOC) == 0)
- continue;
- AllocatedSections.push_back(&Section);
- }
+ for (SectionBase &Section : Obj.sections())
+ if (Section.Flags & SHF_ALLOC)
+ AllocatedSections.push_back(&Section);
layoutSections(make_pointee_range(AllocatedSections), Offset);
// Now that every section has been laid out we just need to compute the total
@@ -1803,10 +1783,9 @@ Error BinaryWriter::finalize() {
// LayoutSections, because we want to truncate the last segment to the end of
// its last section, to match GNU objcopy's behaviour.
TotalSize = 0;
- for (const auto &Section : AllocatedSections) {
+ for (SectionBase *Section : AllocatedSections)
if (Section->Type != SHT_NOBITS)
TotalSize = std::max(TotalSize, Section->Offset + Section->Size);
- }
if (Error E = Buf.allocate(TotalSize))
return E;
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