5606dac67e
The TargetLayout class puts two sections into the same segment if they have equal segment types and the same section flags (SHF_xxx). To be able to merge some sort of sections into the same segment we drop some flags before comparison. For example to merge string sections into Data segment we drop SHF_STRINGS and SHF_MERGE flags. The patch allows TargetLayout descendants to drop some target specific section flags. MIPS target needs that to merge .MIPS.options section which has SHF_MIPS_NOSTRIP flag into the LOAD segment. http://reviews.llvm.org/D9160 llvm-svn: 235487
703 lines
23 KiB
C++
703 lines
23 KiB
C++
//===- lib/ReaderWriter/ELF/TargetLayout.cpp ------------------------------===//
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//
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// The LLVM Linker
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include "TargetLayout.h"
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#include "llvm/ADT/ArrayRef.h"
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#include "llvm/ADT/StringSwitch.h"
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#include "llvm/Support/Errc.h"
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namespace lld {
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namespace elf {
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template <class ELFT>
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typename TargetLayout<ELFT>::SectionOrder
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TargetLayout<ELFT>::getSectionOrder(StringRef name, int32_t contentType,
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int32_t contentPermissions) {
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switch (contentType) {
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case DefinedAtom::typeResolver:
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case DefinedAtom::typeCode:
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return llvm::StringSwitch<typename TargetLayout<ELFT>::SectionOrder>(name)
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.StartsWith(".eh_frame_hdr", ORDER_EH_FRAMEHDR)
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.StartsWith(".eh_frame", ORDER_EH_FRAME)
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.StartsWith(".init", ORDER_INIT)
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.StartsWith(".fini", ORDER_FINI)
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.StartsWith(".hash", ORDER_HASH)
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.Default(ORDER_TEXT);
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case DefinedAtom::typeConstant:
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return ORDER_RODATA;
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case DefinedAtom::typeData:
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case DefinedAtom::typeDataFast:
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return llvm::StringSwitch<typename TargetLayout<ELFT>::SectionOrder>(name)
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.StartsWith(".init_array", ORDER_INIT_ARRAY)
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.StartsWith(".fini_array", ORDER_FINI_ARRAY)
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.StartsWith(".dynamic", ORDER_DYNAMIC)
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.StartsWith(".ctors", ORDER_CTORS)
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.StartsWith(".dtors", ORDER_DTORS)
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.Default(ORDER_DATA);
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case DefinedAtom::typeZeroFill:
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case DefinedAtom::typeZeroFillFast:
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return ORDER_BSS;
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case DefinedAtom::typeGOT:
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return llvm::StringSwitch<typename TargetLayout<ELFT>::SectionOrder>(name)
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.StartsWith(".got.plt", ORDER_GOT_PLT)
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.Default(ORDER_GOT);
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case DefinedAtom::typeStub:
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return ORDER_PLT;
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case DefinedAtom::typeRONote:
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return ORDER_RO_NOTE;
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case DefinedAtom::typeRWNote:
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return ORDER_RW_NOTE;
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case DefinedAtom::typeNoAlloc:
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return ORDER_NOALLOC;
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case DefinedAtom::typeThreadData:
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return ORDER_TDATA;
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case DefinedAtom::typeThreadZeroFill:
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return ORDER_TBSS;
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default:
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// If we get passed in a section push it to OTHER
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if (contentPermissions == DefinedAtom::perm___)
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return ORDER_OTHER;
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return ORDER_NOT_DEFINED;
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}
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}
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/// \brief This maps the input sections to the output section names
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template <class ELFT>
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StringRef TargetLayout<ELFT>::getInputSectionName(const DefinedAtom *da) const {
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if (da->sectionChoice() == DefinedAtom::sectionBasedOnContent) {
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switch (da->contentType()) {
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case DefinedAtom::typeCode:
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return ".text";
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case DefinedAtom::typeData:
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return ".data";
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case DefinedAtom::typeConstant:
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return ".rodata";
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case DefinedAtom::typeZeroFill:
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return ".bss";
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case DefinedAtom::typeThreadData:
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return ".tdata";
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case DefinedAtom::typeThreadZeroFill:
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return ".tbss";
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default:
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break;
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}
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}
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return da->customSectionName();
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}
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/// \brief This maps the input sections to the output section names.
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template <class ELFT>
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StringRef
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TargetLayout<ELFT>::getOutputSectionName(StringRef archivePath,
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StringRef memberPath,
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StringRef inputSectionName) const {
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StringRef outputSectionName;
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if (_linkerScriptSema.hasLayoutCommands()) {
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script::Sema::SectionKey key = {archivePath, memberPath, inputSectionName};
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outputSectionName = _linkerScriptSema.getOutputSection(key);
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if (!outputSectionName.empty())
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return outputSectionName;
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}
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return llvm::StringSwitch<StringRef>(inputSectionName)
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.StartsWith(".text", ".text")
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.StartsWith(".ctors", ".ctors")
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.StartsWith(".dtors", ".dtors")
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.StartsWith(".rodata", ".rodata")
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.StartsWith(".gcc_except_table", ".gcc_except_table")
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.StartsWith(".data.rel.ro", ".data.rel.ro")
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.StartsWith(".data.rel.local", ".data.rel.local")
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.StartsWith(".data", ".data")
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.StartsWith(".tdata", ".tdata")
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.StartsWith(".tbss", ".tbss")
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.StartsWith(".init_array", ".init_array")
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.StartsWith(".fini_array", ".fini_array")
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.Default(inputSectionName);
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}
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/// \brief Gets the segment for a output section
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template <class ELFT>
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typename TargetLayout<ELFT>::SegmentType
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TargetLayout<ELFT>::getSegmentType(Section<ELFT> *section) const {
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switch (section->order()) {
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case ORDER_INTERP:
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return llvm::ELF::PT_INTERP;
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case ORDER_TEXT:
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case ORDER_HASH:
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case ORDER_DYNAMIC_SYMBOLS:
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case ORDER_DYNAMIC_STRINGS:
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case ORDER_DYNAMIC_RELOCS:
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case ORDER_DYNAMIC_PLT_RELOCS:
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case ORDER_REL:
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case ORDER_INIT:
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case ORDER_PLT:
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case ORDER_FINI:
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case ORDER_RODATA:
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case ORDER_EH_FRAME:
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case ORDER_CTORS:
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case ORDER_DTORS:
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return llvm::ELF::PT_LOAD;
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case ORDER_RO_NOTE:
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case ORDER_RW_NOTE:
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return llvm::ELF::PT_NOTE;
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case ORDER_DYNAMIC:
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return llvm::ELF::PT_DYNAMIC;
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case ORDER_EH_FRAMEHDR:
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return llvm::ELF::PT_GNU_EH_FRAME;
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case ORDER_GOT:
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case ORDER_GOT_PLT:
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case ORDER_DATA:
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case ORDER_BSS:
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case ORDER_INIT_ARRAY:
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case ORDER_FINI_ARRAY:
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return llvm::ELF::PT_LOAD;
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case ORDER_TDATA:
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case ORDER_TBSS:
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return llvm::ELF::PT_TLS;
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default:
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return llvm::ELF::PT_NULL;
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}
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}
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template <class ELFT>
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bool TargetLayout<ELFT>::hasOutputSegment(Section<ELFT> *section) {
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switch (section->order()) {
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case ORDER_INTERP:
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case ORDER_HASH:
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case ORDER_DYNAMIC_SYMBOLS:
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case ORDER_DYNAMIC_STRINGS:
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case ORDER_DYNAMIC_RELOCS:
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case ORDER_DYNAMIC_PLT_RELOCS:
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case ORDER_REL:
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case ORDER_INIT:
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case ORDER_PLT:
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case ORDER_TEXT:
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case ORDER_FINI:
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case ORDER_RODATA:
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case ORDER_EH_FRAME:
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case ORDER_EH_FRAMEHDR:
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case ORDER_TDATA:
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case ORDER_TBSS:
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case ORDER_RO_NOTE:
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case ORDER_RW_NOTE:
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case ORDER_DYNAMIC:
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case ORDER_CTORS:
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case ORDER_DTORS:
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case ORDER_GOT:
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case ORDER_GOT_PLT:
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case ORDER_DATA:
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case ORDER_INIT_ARRAY:
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case ORDER_FINI_ARRAY:
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case ORDER_BSS:
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case ORDER_NOALLOC:
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return true;
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default:
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return section->hasOutputSegment();
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}
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}
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template <class ELFT>
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AtomSection<ELFT> *
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TargetLayout<ELFT>::createSection(StringRef sectionName, int32_t contentType,
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DefinedAtom::ContentPermissions permissions,
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SectionOrder sectionOrder) {
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return new (_allocator) AtomSection<ELFT>(_ctx, sectionName, contentType,
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permissions, sectionOrder);
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}
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template <class ELFT>
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AtomSection<ELFT> *
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TargetLayout<ELFT>::getSection(StringRef sectionName, int32_t contentType,
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DefinedAtom::ContentPermissions permissions,
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const DefinedAtom *da) {
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const SectionKey sectionKey(sectionName, permissions, da->file().path());
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SectionOrder sectionOrder =
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getSectionOrder(sectionName, contentType, permissions);
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auto sec = _sectionMap.find(sectionKey);
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if (sec != _sectionMap.end())
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return sec->second;
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AtomSection<ELFT> *newSec =
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createSection(sectionName, contentType, permissions, sectionOrder);
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newSec->setOutputSectionName(getOutputSectionName(
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da->file().archivePath(), da->file().memberPath(), sectionName));
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newSec->setOrder(sectionOrder);
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newSec->setArchiveNameOrPath(da->file().archivePath());
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newSec->setMemberNameOrPath(da->file().memberPath());
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_sections.push_back(newSec);
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_sectionMap.insert(std::make_pair(sectionKey, newSec));
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return newSec;
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}
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template <class ELFT>
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ErrorOr<const AtomLayout *> TargetLayout<ELFT>::addAtom(const Atom *atom) {
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if (const DefinedAtom *definedAtom = dyn_cast<DefinedAtom>(atom)) {
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// HACK: Ignore undefined atoms. We need to adjust the interface so that
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// undefined atoms can still be included in the output symbol table for
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// -noinhibit-exec.
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if (definedAtom->contentType() == DefinedAtom::typeUnknown)
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return make_error_code(llvm::errc::invalid_argument);
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const DefinedAtom::ContentPermissions permissions =
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definedAtom->permissions();
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const DefinedAtom::ContentType contentType = definedAtom->contentType();
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StringRef sectionName = getInputSectionName(definedAtom);
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AtomSection<ELFT> *section =
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getSection(sectionName, contentType, permissions, definedAtom);
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// Add runtime relocations to the .rela section.
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for (const auto &reloc : *definedAtom) {
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bool isLocalReloc = true;
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if (_ctx.isDynamicRelocation(*reloc)) {
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getDynamicRelocationTable()->addRelocation(*definedAtom, *reloc);
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isLocalReloc = false;
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} else if (_ctx.isPLTRelocation(*reloc)) {
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getPLTRelocationTable()->addRelocation(*definedAtom, *reloc);
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isLocalReloc = false;
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}
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if (!reloc->target())
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continue;
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// Ignore undefined atoms that are not target of dynamic relocations
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if (isa<UndefinedAtom>(reloc->target()) && isLocalReloc)
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continue;
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if (_ctx.isCopyRelocation(*reloc)) {
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_copiedDynSymNames.insert(definedAtom->name());
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continue;
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}
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_referencedDynAtoms.insert(reloc->target());
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}
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return section->appendAtom(atom);
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}
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const AbsoluteAtom *absoluteAtom = cast<AbsoluteAtom>(atom);
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// Absolute atoms are not part of any section, they are global for the whole
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// link
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_absoluteAtoms.push_back(
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new (_allocator) AtomLayout(absoluteAtom, 0, absoluteAtom->value()));
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return _absoluteAtoms.back();
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}
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/// Output sections with the same name into a OutputSection
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template <class ELFT> void TargetLayout<ELFT>::createOutputSections() {
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OutputSection<ELFT> *outputSection;
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for (auto &si : _sections) {
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Section<ELFT> *section = dyn_cast<Section<ELFT>>(si);
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if (!section)
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continue;
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const std::pair<StringRef, OutputSection<ELFT> *> currentOutputSection(
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section->outputSectionName(), nullptr);
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std::pair<typename OutputSectionMapT::iterator, bool> outputSectionInsert(
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_outputSectionMap.insert(currentOutputSection));
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if (!outputSectionInsert.second) {
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outputSection = outputSectionInsert.first->second;
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} else {
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outputSection = new (_allocator.Allocate<OutputSection<ELFT>>())
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OutputSection<ELFT>(section->outputSectionName());
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_outputSections.push_back(outputSection);
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outputSectionInsert.first->second = outputSection;
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}
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outputSection->appendSection(section);
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}
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}
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template <class ELFT>
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uint64_t
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TargetLayout<ELFT>::getLookupSectionFlags(const OutputSection<ELFT> *os) const {
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uint64_t flags = os->flags();
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if (!(flags & llvm::ELF::SHF_WRITE) && _ctx.mergeRODataToTextSegment())
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flags &= ~llvm::ELF::SHF_EXECINSTR;
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// Merge string sections into Data segment itself
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flags &= ~(llvm::ELF::SHF_STRINGS | llvm::ELF::SHF_MERGE);
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// Merge the TLS section into the DATA segment itself
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flags &= ~(llvm::ELF::SHF_TLS);
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return flags;
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}
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template <class ELFT> void TargetLayout<ELFT>::assignSectionsToSegments() {
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ScopedTask task(getDefaultDomain(), "assignSectionsToSegments");
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ELFLinkingContext::OutputMagic outputMagic = _ctx.getOutputMagic();
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// sort the sections by their order as defined by the layout
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sortInputSections();
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// Create output sections.
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createOutputSections();
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// Finalize output section layout.
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finalizeOutputSectionLayout();
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// Set the ordinal after sorting the sections
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int ordinal = 1;
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for (auto osi : _outputSections) {
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osi->setOrdinal(ordinal);
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for (auto ai : osi->sections()) {
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ai->setOrdinal(ordinal);
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}
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++ordinal;
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}
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for (auto osi : _outputSections) {
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for (auto section : osi->sections()) {
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if (!hasOutputSegment(section))
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continue;
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osi->setLoadableSection(section->isLoadableSection());
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// Get the segment type for the section
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int64_t segmentType = getSegmentType(section);
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osi->setHasSegment();
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section->setSegmentType(segmentType);
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StringRef segmentName = section->segmentKindToStr();
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uint64_t lookupSectionFlag = getLookupSectionFlags(osi);
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Segment<ELFT> *segment;
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// We need a separate segment for sections that don't have
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// the segment type to be PT_LOAD
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if (segmentType != llvm::ELF::PT_LOAD) {
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const AdditionalSegmentKey key(segmentType, lookupSectionFlag);
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const std::pair<AdditionalSegmentKey, Segment<ELFT> *>
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additionalSegment(key, nullptr);
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std::pair<typename AdditionalSegmentMapT::iterator, bool>
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additionalSegmentInsert(
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_additionalSegmentMap.insert(additionalSegment));
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if (!additionalSegmentInsert.second) {
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segment = additionalSegmentInsert.first->second;
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} else {
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segment =
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new (_allocator) Segment<ELFT>(_ctx, segmentName, segmentType);
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additionalSegmentInsert.first->second = segment;
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_segments.push_back(segment);
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}
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segment->append(section);
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}
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if (segmentType == llvm::ELF::PT_NULL)
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continue;
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// If the output magic is set to OutputMagic::NMAGIC or
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// OutputMagic::OMAGIC, Place the data alongside text in one single
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// segment
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if (outputMagic == ELFLinkingContext::OutputMagic::NMAGIC ||
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outputMagic == ELFLinkingContext::OutputMagic::OMAGIC)
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lookupSectionFlag = llvm::ELF::SHF_EXECINSTR | llvm::ELF::SHF_ALLOC |
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llvm::ELF::SHF_WRITE;
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// Use the flags of the merged Section for the segment
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const SegmentKey key("PT_LOAD", lookupSectionFlag);
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const std::pair<SegmentKey, Segment<ELFT> *> currentSegment(key, nullptr);
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std::pair<typename SegmentMapT::iterator, bool> segmentInsert(
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_segmentMap.insert(currentSegment));
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if (!segmentInsert.second) {
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segment = segmentInsert.first->second;
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} else {
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segment =
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new (_allocator) Segment<ELFT>(_ctx, "PT_LOAD", llvm::ELF::PT_LOAD);
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segmentInsert.first->second = segment;
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_segments.push_back(segment);
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}
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// Insert chunks with linker script expressions that occur at this
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// point, just before appending a new input section
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addExtraChunksToSegment(segment, section->archivePath(),
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section->memberPath(),
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section->inputSectionName());
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segment->append(section);
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}
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}
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if (_ctx.isDynamic() && !_ctx.isDynamicLibrary()) {
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Segment<ELFT> *segment = new (_allocator) ProgramHeaderSegment<ELFT>(_ctx);
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_segments.push_back(segment);
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segment->append(_elfHeader);
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segment->append(_programHeader);
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}
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}
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template <class ELFT> void TargetLayout<ELFT>::assignVirtualAddress() {
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if (_segments.empty())
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return;
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std::sort(_segments.begin(), _segments.end(), Segment<ELFT>::compareSegments);
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uint64_t baseAddress = _ctx.getBaseAddress();
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// HACK: This is a super dirty hack. The elf header and program header are
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// not part of a section, but we need them to be loaded at the base address
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// so that AT_PHDR is set correctly by the loader and so they are accessible
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// at runtime. To do this we simply prepend them to the first loadable Segment
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// and let the layout logic take care of it.
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Segment<ELFT> *firstLoadSegment = nullptr;
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for (auto si : _segments) {
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if (si->segmentType() == llvm::ELF::PT_LOAD) {
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firstLoadSegment = si;
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si->firstSection()->setAlign(si->alignment());
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break;
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}
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}
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assert(firstLoadSegment != nullptr && "No loadable segment!");
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firstLoadSegment->prepend(_programHeader);
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firstLoadSegment->prepend(_elfHeader);
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bool newSegmentHeaderAdded = true;
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bool virtualAddressAssigned = false;
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bool fileOffsetAssigned = false;
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while (true) {
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for (auto si : _segments) {
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si->finalize();
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// Don't add PT_NULL segments into the program header
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if (si->segmentType() != llvm::ELF::PT_NULL)
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newSegmentHeaderAdded = _programHeader->addSegment(si);
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}
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if (!newSegmentHeaderAdded && virtualAddressAssigned)
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break;
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uint64_t address = baseAddress;
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// start assigning virtual addresses
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for (auto &si : _segments) {
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if ((si->segmentType() != llvm::ELF::PT_LOAD) &&
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(si->segmentType() != llvm::ELF::PT_NULL))
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continue;
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if (si->segmentType() == llvm::ELF::PT_NULL) {
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si->assignVirtualAddress(0 /*non loadable*/);
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} else {
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if (virtualAddressAssigned && (address != baseAddress) &&
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(address == si->virtualAddr()))
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break;
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si->assignVirtualAddress(address);
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}
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address = si->virtualAddr() + si->memSize();
|
|
}
|
|
uint64_t baseFileOffset = 0;
|
|
uint64_t fileoffset = baseFileOffset;
|
|
for (auto &si : _segments) {
|
|
if ((si->segmentType() != llvm::ELF::PT_LOAD) &&
|
|
(si->segmentType() != llvm::ELF::PT_NULL))
|
|
continue;
|
|
if (fileOffsetAssigned && (fileoffset != baseFileOffset) &&
|
|
(fileoffset == si->fileOffset()))
|
|
break;
|
|
si->assignFileOffsets(fileoffset);
|
|
fileoffset = si->fileOffset() + si->fileSize();
|
|
}
|
|
virtualAddressAssigned = true;
|
|
fileOffsetAssigned = true;
|
|
_programHeader->resetProgramHeaders();
|
|
}
|
|
Section<ELFT> *section;
|
|
// Fix the offsets of all the atoms within a section
|
|
for (auto &si : _sections) {
|
|
section = dyn_cast<Section<ELFT>>(si);
|
|
if (section && TargetLayout<ELFT>::hasOutputSegment(section))
|
|
section->assignFileOffsets(section->fileOffset());
|
|
}
|
|
// Set the size of the merged Sections
|
|
for (auto osi : _outputSections) {
|
|
uint64_t sectionfileoffset = 0;
|
|
uint64_t startFileOffset = 0;
|
|
uint64_t sectionsize = 0;
|
|
bool isFirstSection = true;
|
|
for (auto si : osi->sections()) {
|
|
if (isFirstSection) {
|
|
startFileOffset = si->fileOffset();
|
|
isFirstSection = false;
|
|
}
|
|
sectionfileoffset = si->fileOffset();
|
|
sectionsize = si->fileSize();
|
|
}
|
|
sectionsize = (sectionfileoffset - startFileOffset) + sectionsize;
|
|
osi->setFileOffset(startFileOffset);
|
|
osi->setSize(sectionsize);
|
|
}
|
|
// Set the virtual addr of the merged Sections
|
|
for (auto osi : _outputSections) {
|
|
uint64_t sectionstartaddr = 0;
|
|
uint64_t startaddr = 0;
|
|
uint64_t sectionsize = 0;
|
|
bool isFirstSection = true;
|
|
for (auto si : osi->sections()) {
|
|
if (isFirstSection) {
|
|
startaddr = si->virtualAddr();
|
|
isFirstSection = false;
|
|
}
|
|
sectionstartaddr = si->virtualAddr();
|
|
sectionsize = si->memSize();
|
|
}
|
|
sectionsize = (sectionstartaddr - startaddr) + sectionsize;
|
|
osi->setMemSize(sectionsize);
|
|
osi->setAddr(startaddr);
|
|
}
|
|
}
|
|
|
|
template <class ELFT>
|
|
void TargetLayout<ELFT>::assignFileOffsetsForMiscSections() {
|
|
uint64_t fileoffset = 0;
|
|
uint64_t size = 0;
|
|
for (auto si : _segments) {
|
|
// Don't calculate offsets from non loadable segments
|
|
if ((si->segmentType() != llvm::ELF::PT_LOAD) &&
|
|
(si->segmentType() != llvm::ELF::PT_NULL))
|
|
continue;
|
|
fileoffset = si->fileOffset();
|
|
size = si->fileSize();
|
|
}
|
|
fileoffset = fileoffset + size;
|
|
Section<ELFT> *section;
|
|
for (auto si : _sections) {
|
|
section = dyn_cast<Section<ELFT>>(si);
|
|
if (section && TargetLayout<ELFT>::hasOutputSegment(section))
|
|
continue;
|
|
fileoffset = llvm::RoundUpToAlignment(fileoffset, si->alignment());
|
|
si->setFileOffset(fileoffset);
|
|
si->setVirtualAddr(0);
|
|
fileoffset += si->fileSize();
|
|
}
|
|
}
|
|
|
|
template <class ELFT> void TargetLayout<ELFT>::sortInputSections() {
|
|
// First, sort according to default layout's order
|
|
std::stable_sort(
|
|
_sections.begin(), _sections.end(),
|
|
[](Chunk<ELFT> *A, Chunk<ELFT> *B) { return A->order() < B->order(); });
|
|
|
|
if (!_linkerScriptSema.hasLayoutCommands())
|
|
return;
|
|
|
|
// Sort the sections by their order as defined by the linker script
|
|
std::stable_sort(
|
|
this->_sections.begin(), this->_sections.end(),
|
|
[this](Chunk<ELFT> *A, Chunk<ELFT> *B) {
|
|
auto *a = dyn_cast<Section<ELFT>>(A);
|
|
auto *b = dyn_cast<Section<ELFT>>(B);
|
|
|
|
if (a == nullptr)
|
|
return false;
|
|
if (b == nullptr)
|
|
return true;
|
|
|
|
return _linkerScriptSema.less(
|
|
{a->archivePath(), a->memberPath(), a->inputSectionName()},
|
|
{b->archivePath(), b->memberPath(), b->inputSectionName()});
|
|
});
|
|
// Now try to arrange sections with no mapping rules to sections with
|
|
// similar content
|
|
auto p = this->_sections.begin();
|
|
// Find first section that has no assigned rule id
|
|
while (p != this->_sections.end()) {
|
|
auto *sect = dyn_cast<AtomSection<ELFT>>(*p);
|
|
if (!sect)
|
|
break;
|
|
|
|
if (!_linkerScriptSema.hasMapping({sect->archivePath(), sect->memberPath(),
|
|
sect->inputSectionName()}))
|
|
break;
|
|
|
|
++p;
|
|
}
|
|
// For all sections that have no assigned rule id, try to move them near a
|
|
// section with similar contents
|
|
if (p != this->_sections.begin()) {
|
|
for (; p != this->_sections.end(); ++p) {
|
|
auto q = p;
|
|
--q;
|
|
while (q != this->_sections.begin() &&
|
|
(*q)->getContentType() != (*p)->getContentType())
|
|
--q;
|
|
if ((*q)->getContentType() != (*p)->getContentType())
|
|
continue;
|
|
++q;
|
|
for (auto i = p; i != q;) {
|
|
auto next = i--;
|
|
std::iter_swap(i, next);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
template <class ELFT>
|
|
const AtomLayout *
|
|
TargetLayout<ELFT>::findAtomLayoutByName(StringRef name) const {
|
|
for (auto sec : _sections)
|
|
if (auto section = dyn_cast<Section<ELFT>>(sec))
|
|
if (auto *al = section->findAtomLayoutByName(name))
|
|
return al;
|
|
return nullptr;
|
|
}
|
|
|
|
template <class ELFT>
|
|
void TargetLayout<ELFT>::addExtraChunksToSegment(Segment<ELFT> *segment,
|
|
StringRef archivePath,
|
|
StringRef memberPath,
|
|
StringRef sectionName) {
|
|
if (!_linkerScriptSema.hasLayoutCommands())
|
|
return;
|
|
std::vector<const script::SymbolAssignment *> exprs =
|
|
_linkerScriptSema.getExprs({archivePath, memberPath, sectionName});
|
|
for (auto expr : exprs) {
|
|
auto expChunk =
|
|
new (this->_allocator) ExpressionChunk<ELFT>(this->_ctx, expr);
|
|
segment->append(expChunk);
|
|
}
|
|
}
|
|
|
|
template <class ELFT>
|
|
RelocationTable<ELFT> *TargetLayout<ELFT>::getDynamicRelocationTable() {
|
|
if (!_dynamicRelocationTable) {
|
|
_dynamicRelocationTable = std::move(createRelocationTable(
|
|
_ctx.isRelaOutputFormat() ? ".rela.dyn" : ".rel.dyn",
|
|
ORDER_DYNAMIC_RELOCS));
|
|
addSection(_dynamicRelocationTable.get());
|
|
}
|
|
return _dynamicRelocationTable.get();
|
|
}
|
|
|
|
template <class ELFT>
|
|
RelocationTable<ELFT> *TargetLayout<ELFT>::getPLTRelocationTable() {
|
|
if (!_pltRelocationTable) {
|
|
_pltRelocationTable = std::move(createRelocationTable(
|
|
_ctx.isRelaOutputFormat() ? ".rela.plt" : ".rel.plt",
|
|
ORDER_DYNAMIC_PLT_RELOCS));
|
|
addSection(_pltRelocationTable.get());
|
|
}
|
|
return _pltRelocationTable.get();
|
|
}
|
|
|
|
template <class ELFT> uint64_t TargetLayout<ELFT>::getTLSSize() const {
|
|
for (const auto &phdr : *_programHeader)
|
|
if (phdr->p_type == llvm::ELF::PT_TLS)
|
|
return phdr->p_memsz;
|
|
return 0;
|
|
}
|
|
|
|
template class TargetLayout<ELF32LE>;
|
|
template class TargetLayout<ELF32BE>;
|
|
template class TargetLayout<ELF64LE>;
|
|
template class TargetLayout<ELF64BE>;
|
|
|
|
} // end namespace elf
|
|
} // end namespace lld
|