diff options
Diffstat (limited to 'lld/lib/ReaderWriter/ELF/HeaderChunks.cpp')
| -rw-r--r-- | lld/lib/ReaderWriter/ELF/HeaderChunks.cpp | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/lld/lib/ReaderWriter/ELF/HeaderChunks.cpp b/lld/lib/ReaderWriter/ELF/HeaderChunks.cpp new file mode 100644 index 00000000000..0bd4b3e03cf --- /dev/null +++ b/lld/lib/ReaderWriter/ELF/HeaderChunks.cpp @@ -0,0 +1,205 @@ +//===- lib/ReaderWriter/ELF/HeaderChunks.cpp ------------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "HeaderChunks.h" +#include "TargetLayout.h" +#include "llvm/ADT/STLExtras.h" + +namespace lld { +namespace elf { + +template <class ELFT> void ELFHeader<ELFT>::finalize() { + _eh.e_ident[llvm::ELF::EI_CLASS] = + (ELFT::Is64Bits) ? llvm::ELF::ELFCLASS64 : llvm::ELF::ELFCLASS32; + _eh.e_ident[llvm::ELF::EI_DATA] = + (ELFT::TargetEndianness == llvm::support::little) + ? llvm::ELF::ELFDATA2LSB + : llvm::ELF::ELFDATA2MSB; + _eh.e_type = this->_ctx.getOutputELFType(); + _eh.e_machine = this->_ctx.getOutputMachine(); +} + +template <class ELFT> +ELFHeader<ELFT>::ELFHeader(const ELFLinkingContext &ctx) + : Chunk<ELFT>("elfhdr", Chunk<ELFT>::Kind::ELFHeader, ctx) { + this->_alignment = ELFT::Is64Bits ? 8 : 4; + this->_fsize = sizeof(Elf_Ehdr); + this->_msize = sizeof(Elf_Ehdr); + memset(_eh.e_ident, 0, llvm::ELF::EI_NIDENT); + e_ident(llvm::ELF::EI_MAG0, 0x7f); + e_ident(llvm::ELF::EI_MAG1, 'E'); + e_ident(llvm::ELF::EI_MAG2, 'L'); + e_ident(llvm::ELF::EI_MAG3, 'F'); + e_ehsize(sizeof(Elf_Ehdr)); + e_flags(0); +} + +template <class ELFT> +void ELFHeader<ELFT>::write(ELFWriter *writer, TargetLayout<ELFT> &layout, + llvm::FileOutputBuffer &buffer) { + uint8_t *chunkBuffer = buffer.getBufferStart(); + uint8_t *atomContent = chunkBuffer + this->fileOffset(); + memcpy(atomContent, &_eh, fileSize()); +} + +template <class ELFT> +bool ProgramHeader<ELFT>::addSegment(Segment<ELFT> *segment) { + bool allocatedNew = false; + ELFLinkingContext::OutputMagic outputMagic = this->_ctx.getOutputMagic(); + // For segments that are not a loadable segment, we + // just pick the values directly from the segment as there + // wouldnt be any slices within that + if (segment->segmentType() != llvm::ELF::PT_LOAD) { + Elf_Phdr *phdr = allocateProgramHeader(allocatedNew); + phdr->p_type = segment->segmentType(); + phdr->p_offset = segment->fileOffset(); + phdr->p_vaddr = segment->virtualAddr(); + phdr->p_paddr = segment->virtualAddr(); + phdr->p_filesz = segment->fileSize(); + phdr->p_memsz = segment->memSize(); + phdr->p_flags = segment->flags(); + phdr->p_align = segment->alignment(); + this->_fsize = fileSize(); + this->_msize = this->_fsize; + return allocatedNew; + } + // For all other segments, use the slice + // to derive program headers + for (auto slice : segment->slices()) { + Elf_Phdr *phdr = allocateProgramHeader(allocatedNew); + phdr->p_type = segment->segmentType(); + phdr->p_offset = slice->fileOffset(); + phdr->p_vaddr = slice->virtualAddr(); + phdr->p_paddr = slice->virtualAddr(); + phdr->p_filesz = slice->fileSize(); + phdr->p_memsz = slice->memSize(); + phdr->p_flags = segment->flags(); + phdr->p_align = slice->alignment(); + uint64_t segPageSize = segment->pageSize(); + uint64_t sliceAlign = slice->alignment(); + // Alignment of PT_LOAD segments are set to the page size, but if the + // alignment of the slice is greater than the page size, set the alignment + // of the segment appropriately. + if (outputMagic != ELFLinkingContext::OutputMagic::NMAGIC && + outputMagic != ELFLinkingContext::OutputMagic::OMAGIC) { + phdr->p_align = + (phdr->p_type == llvm::ELF::PT_LOAD) + ? (segPageSize < sliceAlign) ? sliceAlign : segPageSize + : sliceAlign; + } else + phdr->p_align = slice->alignment(); + } + this->_fsize = fileSize(); + this->_msize = this->_fsize; + + return allocatedNew; +} + +template <class ELFT> +void ProgramHeader<ELFT>::write(ELFWriter *writer, TargetLayout<ELFT> &layout, + llvm::FileOutputBuffer &buffer) { + uint8_t *chunkBuffer = buffer.getBufferStart(); + uint8_t *dest = chunkBuffer + this->fileOffset(); + for (auto phi : _ph) { + memcpy(dest, phi, sizeof(Elf_Phdr)); + dest += sizeof(Elf_Phdr); + } +} + +template <class ELFT> +typename ProgramHeader<ELFT>::Elf_Phdr * +ProgramHeader<ELFT>::allocateProgramHeader(bool &allocatedNew) { + Elf_Phdr *phdr; + if (_phi == _ph.end()) { + phdr = new (_allocator) Elf_Phdr; + _ph.push_back(phdr); + _phi = _ph.end(); + allocatedNew = true; + } else { + phdr = (*_phi); + ++_phi; + } + return phdr; +} + +template <class ELFT> +SectionHeader<ELFT>::SectionHeader(const ELFLinkingContext &ctx, int32_t order) + : Chunk<ELFT>("shdr", Chunk<ELFT>::Kind::SectionHeader, ctx) { + this->_fsize = 0; + this->_alignment = 8; + this->setOrder(order); + // The first element in the list is always NULL + Elf_Shdr *nullshdr = new (_sectionAllocate.Allocate<Elf_Shdr>()) Elf_Shdr; + ::memset(nullshdr, 0, sizeof(Elf_Shdr)); + _sectionInfo.push_back(nullshdr); + this->_fsize += sizeof(Elf_Shdr); +} + +template <class ELFT> +void SectionHeader<ELFT>::appendSection(OutputSection<ELFT> *section) { + Elf_Shdr *shdr = new (_sectionAllocate.Allocate<Elf_Shdr>()) Elf_Shdr; + shdr->sh_name = _stringSection->addString(section->name()); + shdr->sh_type = section->type(); + shdr->sh_flags = section->flags(); + shdr->sh_offset = section->fileOffset(); + shdr->sh_addr = section->virtualAddr(); + if (section->isLoadableSection()) + shdr->sh_size = section->memSize(); + else + shdr->sh_size = section->fileSize(); + shdr->sh_link = section->link(); + shdr->sh_info = section->shinfo(); + shdr->sh_addralign = section->alignment(); + shdr->sh_entsize = section->entsize(); + _sectionInfo.push_back(shdr); +} + +template <class ELFT> +void SectionHeader<ELFT>::updateSection(Section<ELFT> *section) { + Elf_Shdr *shdr = _sectionInfo[section->ordinal()]; + shdr->sh_type = section->getType(); + shdr->sh_flags = section->getFlags(); + shdr->sh_offset = section->fileOffset(); + shdr->sh_addr = section->virtualAddr(); + shdr->sh_size = section->fileSize(); + shdr->sh_link = section->getLink(); + shdr->sh_info = section->getInfo(); + shdr->sh_addralign = section->alignment(); + shdr->sh_entsize = section->getEntSize(); +} + +template <class ELFT> +void SectionHeader<ELFT>::write(ELFWriter *writer, TargetLayout<ELFT> &layout, + llvm::FileOutputBuffer &buffer) { + uint8_t *chunkBuffer = buffer.getBufferStart(); + uint8_t *dest = chunkBuffer + this->fileOffset(); + for (auto shi : _sectionInfo) { + memcpy(dest, shi, sizeof(Elf_Shdr)); + dest += sizeof(Elf_Shdr); + } + _stringSection->write(writer, layout, buffer); +} + +template class ELFHeader<ELF32LE>; +template class ELFHeader<ELF32BE>; +template class ELFHeader<ELF64LE>; +template class ELFHeader<ELF64BE>; + +template class ProgramHeader<ELF32LE>; +template class ProgramHeader<ELF32BE>; +template class ProgramHeader<ELF64LE>; +template class ProgramHeader<ELF64BE>; + +template class SectionHeader<ELF32LE>; +template class SectionHeader<ELF32BE>; +template class SectionHeader<ELF64LE>; +template class SectionHeader<ELF64BE>; + +} // end namespace elf +} // end namespace lld |
