Invert the section relocation map.

It now points from rel section to section. Use it to set sh_info, avoiding
a brittle name lookup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228889 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Rafael Espindola 2015-02-11 23:38:33 +00:00
parent 723be8820c
commit 9fbdbaa2d1

View File

@ -273,9 +273,10 @@ class ELFObjectWriter : public MCObjectWriter {
void ExecutePostLayoutBinding(MCAssembler &Asm,
const MCAsmLayout &Layout) override;
void WriteSectionHeader(MCAssembler &Asm, const GroupMapTy &GroupMap,
void writeSectionHeader(MCAssembler &Asm, const GroupMapTy &GroupMap,
const MCAsmLayout &Layout,
const SectionIndexMapTy &SectionIndexMap,
const RelMapTy &RelMap,
const SectionOffsetMapTy &SectionOffsetMap);
void ComputeSectionOrder(MCAssembler &Asm,
@ -298,8 +299,9 @@ class ELFObjectWriter : public MCObjectWriter {
bool IsPCRel) const override;
void WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
void WriteSection(MCAssembler &Asm,
void writeSection(MCAssembler &Asm,
const SectionIndexMapTy &SectionIndexMap,
const RelMapTy &RelMap,
uint32_t GroupSymbolIndex,
uint64_t Offset, uint64_t Size, uint64_t Alignment,
const MCSectionELF &Section);
@ -968,7 +970,7 @@ void ELFObjectWriter::computeIndexMap(MCAssembler &Asm,
if (MCSectionData *RelSD = createRelocationSection(Asm, SD)) {
const MCSectionELF *RelSection =
static_cast<const MCSectionELF *>(&RelSD->getSection());
RelMap[&Section] = RelSection;
RelMap[RelSection] = &Section;
SectionIndexMap[RelSection] = Index++;
}
}
@ -1300,20 +1302,21 @@ void ELFObjectWriter::CompressDebugSections(MCAssembler &Asm,
void ELFObjectWriter::WriteRelocations(MCAssembler &Asm, MCAsmLayout &Layout,
const RelMapTy &RelMap) {
for (MCAssembler::const_iterator it = Asm.begin(),
ie = Asm.end(); it != ie; ++it) {
const MCSectionData &SD = *it;
const MCSectionELF &Section =
static_cast<const MCSectionELF&>(SD.getSection());
for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) {
MCSectionData &RelSD = *it;
const MCSectionELF &RelSection =
static_cast<const MCSectionELF &>(RelSD.getSection());
const MCSectionELF *RelaSection = RelMap.lookup(&Section);
if (!RelaSection)
unsigned Type = RelSection.getType();
if (Type != ELF::SHT_REL && Type != ELF::SHT_RELA)
continue;
MCSectionData &RelaSD = Asm.getOrCreateSectionData(*RelaSection);
RelaSD.setAlignment(is64Bit() ? 8 : 4);
MCDataFragment *F = new MCDataFragment(&RelaSD);
WriteRelocationsFragment(Asm, F, &*it);
const MCSectionELF *Section = RelMap.lookup(&RelSection);
MCSectionData &SD = Asm.getOrCreateSectionData(*Section);
RelSD.setAlignment(is64Bit() ? 8 : 4);
MCDataFragment *F = new MCDataFragment(&RelSD);
WriteRelocationsFragment(Asm, F, &SD);
}
}
@ -1492,8 +1495,9 @@ void ELFObjectWriter::createIndexedSections(MCAssembler &Asm,
}
}
void ELFObjectWriter::WriteSection(MCAssembler &Asm,
void ELFObjectWriter::writeSection(MCAssembler &Asm,
const SectionIndexMapTy &SectionIndexMap,
const RelMapTy &RelMap,
uint32_t GroupSymbolIndex,
uint64_t Offset, uint64_t Size,
uint64_t Alignment,
@ -1511,15 +1515,7 @@ void ELFObjectWriter::WriteSection(MCAssembler &Asm,
case ELF::SHT_RELA: {
sh_link = SymbolTableIndex;
assert(sh_link && ".symtab not found");
// Remove ".rel" and ".rela" prefixes.
unsigned SecNameLen = (Section.getType() == ELF::SHT_REL) ? 4 : 5;
StringRef SectionName = Section.getSectionName().substr(SecNameLen);
StringRef GroupName =
Section.getGroup() ? Section.getGroup()->getName() : "";
const MCSectionELF *InfoSection = Asm.getContext().getELFSection(
SectionName, ELF::SHT_PROGBITS, 0, 0, GroupName);
const MCSectionELF *InfoSection = RelMap.find(&Section)->second;
sh_info = SectionIndexMap.lookup(InfoSection);
break;
}
@ -1630,11 +1626,10 @@ void ELFObjectWriter::WriteDataSectionData(MCAssembler &Asm,
}
}
void ELFObjectWriter::WriteSectionHeader(MCAssembler &Asm,
const GroupMapTy &GroupMap,
const MCAsmLayout &Layout,
const SectionIndexMapTy &SectionIndexMap,
const SectionOffsetMapTy &SectionOffsetMap) {
void ELFObjectWriter::writeSectionHeader(
MCAssembler &Asm, const GroupMapTy &GroupMap, const MCAsmLayout &Layout,
const SectionIndexMapTy &SectionIndexMap, const RelMapTy &RelMap,
const SectionOffsetMapTy &SectionOffsetMap) {
const unsigned NumSections = Asm.size() + 1;
std::vector<const MCSectionELF*> Sections;
@ -1665,7 +1660,7 @@ void ELFObjectWriter::WriteSectionHeader(MCAssembler &Asm,
uint64_t Size = GetSectionAddressSize(Layout, SD);
WriteSection(Asm, SectionIndexMap, GroupSymbolIndex,
writeSection(Asm, SectionIndexMap, RelMap, GroupSymbolIndex,
SectionOffsetMap.lookup(&Section), Size,
SD.getAlignment(), Section);
}
@ -1785,7 +1780,7 @@ void ELFObjectWriter::WriteObject(MCAssembler &Asm,
WriteZeros(Padding);
// ... then the section header table ...
WriteSectionHeader(Asm, GroupMap, Layout, SectionIndexMap,
writeSectionHeader(Asm, GroupMap, Layout, SectionIndexMap, RelMap,
SectionOffsetMap);
// ... and then the remaining sections ...