forked from OSchip/llvm-project
1817 lines
55 KiB
C++
1817 lines
55 KiB
C++
//===- LinkerScript.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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//
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// This file contains the parser/evaluator of the linker script.
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// It parses a linker script and write the result to Config or ScriptConfig
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// objects.
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//
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// If SECTIONS command is used, a ScriptConfig contains an AST
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// of the command which will later be consumed by createSections() and
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// assignAddresses().
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//
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//===----------------------------------------------------------------------===//
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#include "LinkerScript.h"
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#include "Config.h"
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#include "Driver.h"
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#include "InputSection.h"
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#include "OutputSections.h"
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#include "ScriptParser.h"
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#include "Strings.h"
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#include "Symbols.h"
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#include "SymbolTable.h"
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#include "Target.h"
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#include "Writer.h"
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#include "llvm/ADT/StringSwitch.h"
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#include "llvm/Support/ELF.h"
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#include "llvm/Support/FileSystem.h"
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#include "llvm/Support/MemoryBuffer.h"
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#include "llvm/Support/Path.h"
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#include "llvm/Support/StringSaver.h"
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using namespace llvm;
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using namespace llvm::ELF;
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using namespace llvm::object;
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using namespace llvm::support::endian;
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using namespace lld;
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using namespace lld::elf;
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LinkerScriptBase *elf::ScriptBase;
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ScriptConfiguration *elf::ScriptConfig;
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template <class ELFT> static void addRegular(SymbolAssignment *Cmd) {
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Symbol *Sym = Symtab<ELFT>::X->addRegular(Cmd->Name, STB_GLOBAL, STV_DEFAULT);
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Sym->Visibility = Cmd->Hidden ? STV_HIDDEN : STV_DEFAULT;
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Cmd->Sym = Sym->body();
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// If we have no SECTIONS then we don't have '.' and don't call
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// assignAddresses(). We calculate symbol value immediately in this case.
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if (!ScriptConfig->HasSections)
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cast<DefinedRegular<ELFT>>(Cmd->Sym)->Value = Cmd->Expression(0);
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}
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template <class ELFT> static void addSynthetic(SymbolAssignment *Cmd) {
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Symbol *Sym = Symtab<ELFT>::X->addSynthetic(
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Cmd->Name, nullptr, 0, Cmd->Hidden ? STV_HIDDEN : STV_DEFAULT);
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Cmd->Sym = Sym->body();
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}
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template <class ELFT> static void addSymbol(SymbolAssignment *Cmd) {
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if (Cmd->IsAbsolute)
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addRegular<ELFT>(Cmd);
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else
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addSynthetic<ELFT>(Cmd);
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}
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// If a symbol was in PROVIDE(), we need to define it only when
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// it is an undefined symbol.
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template <class ELFT> static bool shouldDefine(SymbolAssignment *Cmd) {
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if (Cmd->Name == ".")
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return false;
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if (!Cmd->Provide)
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return true;
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SymbolBody *B = Symtab<ELFT>::X->find(Cmd->Name);
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return B && B->isUndefined();
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}
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bool SymbolAssignment::classof(const BaseCommand *C) {
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return C->Kind == AssignmentKind;
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}
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bool OutputSectionCommand::classof(const BaseCommand *C) {
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return C->Kind == OutputSectionKind;
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}
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bool InputSectionDescription::classof(const BaseCommand *C) {
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return C->Kind == InputSectionKind;
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}
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bool AssertCommand::classof(const BaseCommand *C) {
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return C->Kind == AssertKind;
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}
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bool BytesDataCommand::classof(const BaseCommand *C) {
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return C->Kind == BytesDataKind;
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}
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template <class ELFT> static bool isDiscarded(InputSectionBase<ELFT> *S) {
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return !S || !S->Live;
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}
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template <class ELFT> LinkerScript<ELFT>::LinkerScript() {}
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template <class ELFT> LinkerScript<ELFT>::~LinkerScript() {}
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template <class ELFT>
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bool LinkerScript<ELFT>::shouldKeep(InputSectionBase<ELFT> *S) {
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for (InputSectionDescription *ID : Opt.KeptSections) {
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StringRef Filename = S->getFile()->getName();
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if (!ID->FileRe.match(sys::path::filename(Filename)))
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continue;
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for (SectionPattern &P : ID->SectionPatterns)
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if (P.SectionRe.match(S->Name))
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return true;
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}
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return false;
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}
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static bool comparePriority(InputSectionData *A, InputSectionData *B) {
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return getPriority(A->Name) < getPriority(B->Name);
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}
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static bool compareName(InputSectionData *A, InputSectionData *B) {
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return A->Name < B->Name;
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}
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static bool compareAlignment(InputSectionData *A, InputSectionData *B) {
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// ">" is not a mistake. Larger alignments are placed before smaller
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// alignments in order to reduce the amount of padding necessary.
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// This is compatible with GNU.
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return A->Alignment > B->Alignment;
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}
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static std::function<bool(InputSectionData *, InputSectionData *)>
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getComparator(SortSectionPolicy K) {
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switch (K) {
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case SortSectionPolicy::Alignment:
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return compareAlignment;
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case SortSectionPolicy::Name:
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return compareName;
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case SortSectionPolicy::Priority:
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return comparePriority;
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default:
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llvm_unreachable("unknown sort policy");
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}
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}
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template <class ELFT>
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static bool matchConstraints(ArrayRef<InputSectionBase<ELFT> *> Sections,
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ConstraintKind Kind) {
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if (Kind == ConstraintKind::NoConstraint)
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return true;
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bool IsRW = llvm::any_of(Sections, [=](InputSectionData *Sec2) {
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auto *Sec = static_cast<InputSectionBase<ELFT> *>(Sec2);
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return Sec->getSectionHdr()->sh_flags & SHF_WRITE;
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});
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return (IsRW && Kind == ConstraintKind::ReadWrite) ||
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(!IsRW && Kind == ConstraintKind::ReadOnly);
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}
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static void sortSections(InputSectionData **Begin, InputSectionData **End,
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SortSectionPolicy K) {
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if (K != SortSectionPolicy::Default && K != SortSectionPolicy::None)
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std::stable_sort(Begin, End, getComparator(K));
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}
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// Compute and remember which sections the InputSectionDescription matches.
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template <class ELFT>
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void LinkerScript<ELFT>::computeInputSections(InputSectionDescription *I) {
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// Collects all sections that satisfy constraints of I
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// and attach them to I.
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for (SectionPattern &Pat : I->SectionPatterns) {
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size_t SizeBefore = I->Sections.size();
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for (ObjectFile<ELFT> *F : Symtab<ELFT>::X->getObjectFiles()) {
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StringRef Filename = sys::path::filename(F->getName());
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if (!I->FileRe.match(Filename) || Pat.ExcludedFileRe.match(Filename))
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continue;
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for (InputSectionBase<ELFT> *S : F->getSections())
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if (!isDiscarded(S) && !S->OutSec && Pat.SectionRe.match(S->Name))
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I->Sections.push_back(S);
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if (Pat.SectionRe.match("COMMON"))
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I->Sections.push_back(CommonInputSection<ELFT>::X);
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}
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// Sort sections as instructed by SORT-family commands and --sort-section
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// option. Because SORT-family commands can be nested at most two depth
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// (e.g. SORT_BY_NAME(SORT_BY_ALIGNMENT(.text.*))) and because the command
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// line option is respected even if a SORT command is given, the exact
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// behavior we have here is a bit complicated. Here are the rules.
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//
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// 1. If two SORT commands are given, --sort-section is ignored.
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// 2. If one SORT command is given, and if it is not SORT_NONE,
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// --sort-section is handled as an inner SORT command.
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// 3. If one SORT command is given, and if it is SORT_NONE, don't sort.
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// 4. If no SORT command is given, sort according to --sort-section.
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InputSectionData **Begin = I->Sections.data() + SizeBefore;
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InputSectionData **End = I->Sections.data() + I->Sections.size();
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if (Pat.SortOuter != SortSectionPolicy::None) {
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if (Pat.SortInner == SortSectionPolicy::Default)
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sortSections(Begin, End, Config->SortSection);
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else
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sortSections(Begin, End, Pat.SortInner);
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sortSections(Begin, End, Pat.SortOuter);
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}
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}
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// We do not add duplicate input sections, so mark them with a dummy output
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// section for now.
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for (InputSectionData *S : I->Sections) {
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auto *S2 = static_cast<InputSectionBase<ELFT> *>(S);
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S2->OutSec = (OutputSectionBase<ELFT> *)-1;
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}
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}
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template <class ELFT>
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void LinkerScript<ELFT>::discard(ArrayRef<InputSectionBase<ELFT> *> V) {
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for (InputSectionBase<ELFT> *S : V) {
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S->Live = false;
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reportDiscarded(S);
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}
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}
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template <class ELFT>
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std::vector<InputSectionBase<ELFT> *>
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LinkerScript<ELFT>::createInputSectionList(OutputSectionCommand &OutCmd) {
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std::vector<InputSectionBase<ELFT> *> Ret;
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for (const std::unique_ptr<BaseCommand> &Base : OutCmd.Commands) {
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auto *Cmd = dyn_cast<InputSectionDescription>(Base.get());
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if (!Cmd)
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continue;
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computeInputSections(Cmd);
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for (InputSectionData *S : Cmd->Sections)
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Ret.push_back(static_cast<InputSectionBase<ELFT> *>(S));
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}
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// After we created final list we should now set OutSec pointer to null,
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// instead of -1. Otherwise we may get a crash when writing relocs, in
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// case section is discarded by linker script
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for (InputSectionBase<ELFT> *S : Ret)
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S->OutSec = nullptr;
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return Ret;
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}
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template <class ELFT>
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static SectionKey<ELFT::Is64Bits> createKey(InputSectionBase<ELFT> *C,
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StringRef OutsecName) {
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// When using linker script the merge rules are different.
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// Unfortunately, linker scripts are name based. This means that expressions
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// like *(.foo*) can refer to multiple input sections that would normally be
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// placed in different output sections. We cannot put them in different
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// output sections or we would produce wrong results for
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// start = .; *(.foo.*) end = .; *(.bar)
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// and a mapping of .foo1 and .bar1 to one section and .foo2 and .bar2 to
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// another. The problem is that there is no way to layout those output
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// sections such that the .foo sections are the only thing between the
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// start and end symbols.
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// An extra annoyance is that we cannot simply disable merging of the contents
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// of SHF_MERGE sections, but our implementation requires one output section
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// per "kind" (string or not, which size/aligment).
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// Fortunately, creating symbols in the middle of a merge section is not
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// supported by bfd or gold, so we can just create multiple section in that
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// case.
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const typename ELFT::Shdr *H = C->getSectionHdr();
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typedef typename ELFT::uint uintX_t;
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uintX_t Flags = H->sh_flags & (SHF_MERGE | SHF_STRINGS);
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uintX_t Alignment = 0;
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if (isa<MergeInputSection<ELFT>>(C))
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Alignment = std::max(H->sh_addralign, H->sh_entsize);
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return SectionKey<ELFT::Is64Bits>{OutsecName, /*Type*/ 0, Flags, Alignment};
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}
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template <class ELFT>
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void LinkerScript<ELFT>::addSection(OutputSectionFactory<ELFT> &Factory,
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InputSectionBase<ELFT> *Sec,
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StringRef Name) {
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OutputSectionBase<ELFT> *OutSec;
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bool IsNew;
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std::tie(OutSec, IsNew) = Factory.create(createKey(Sec, Name), Sec);
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if (IsNew)
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OutputSections->push_back(OutSec);
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OutSec->addSection(Sec);
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}
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template <class ELFT>
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void LinkerScript<ELFT>::processCommands(OutputSectionFactory<ELFT> &Factory) {
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for (unsigned I = 0; I < Opt.Commands.size(); ++I) {
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auto Iter = Opt.Commands.begin() + I;
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const std::unique_ptr<BaseCommand> &Base1 = *Iter;
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if (auto *Cmd = dyn_cast<SymbolAssignment>(Base1.get())) {
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if (shouldDefine<ELFT>(Cmd))
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addRegular<ELFT>(Cmd);
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continue;
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}
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if (auto *Cmd = dyn_cast<AssertCommand>(Base1.get())) {
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// If we don't have SECTIONS then output sections have already been
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// created by Writer<ELFT>. The LinkerScript<ELFT>::assignAddresses
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// will not be called, so ASSERT should be evaluated now.
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if (!Opt.HasSections)
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Cmd->Expression(0);
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continue;
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}
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if (auto *Cmd = dyn_cast<OutputSectionCommand>(Base1.get())) {
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std::vector<InputSectionBase<ELFT> *> V = createInputSectionList(*Cmd);
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if (Cmd->Name == "/DISCARD/") {
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discard(V);
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continue;
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}
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if (!matchConstraints<ELFT>(V, Cmd->Constraint)) {
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for (InputSectionBase<ELFT> *S : V)
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S->OutSec = nullptr;
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Opt.Commands.erase(Iter);
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--I;
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continue;
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}
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for (const std::unique_ptr<BaseCommand> &Base : Cmd->Commands)
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if (auto *OutCmd = dyn_cast<SymbolAssignment>(Base.get()))
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if (shouldDefine<ELFT>(OutCmd))
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addSymbol<ELFT>(OutCmd);
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if (V.empty())
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continue;
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for (InputSectionBase<ELFT> *Sec : V) {
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addSection(Factory, Sec, Cmd->Name);
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if (uint32_t Subalign = Cmd->SubalignExpr ? Cmd->SubalignExpr(0) : 0)
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Sec->Alignment = Subalign;
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}
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}
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}
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}
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template <class ELFT>
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void LinkerScript<ELFT>::createSections(OutputSectionFactory<ELFT> &Factory) {
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processCommands(Factory);
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// Add orphan sections.
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for (ObjectFile<ELFT> *F : Symtab<ELFT>::X->getObjectFiles())
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for (InputSectionBase<ELFT> *S : F->getSections())
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if (!isDiscarded(S) && !S->OutSec)
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addSection(Factory, S, getOutputSectionName(S->Name, Opt.Alloc));
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}
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// Sets value of a section-defined symbol. Two kinds of
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// symbols are processed: synthetic symbols, whose value
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// is an offset from beginning of section and regular
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// symbols whose value is absolute.
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template <class ELFT>
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static void assignSectionSymbol(SymbolAssignment *Cmd,
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OutputSectionBase<ELFT> *Sec,
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typename ELFT::uint Off) {
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if (!Cmd->Sym)
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return;
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if (auto *Body = dyn_cast<DefinedSynthetic<ELFT>>(Cmd->Sym)) {
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Body->Section = Sec;
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Body->Value = Cmd->Expression(Sec->getVA() + Off) - Sec->getVA();
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return;
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}
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auto *Body = cast<DefinedRegular<ELFT>>(Cmd->Sym);
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Body->Value = Cmd->Expression(Sec->getVA() + Off);
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}
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template <class ELFT> static bool isTbss(OutputSectionBase<ELFT> *Sec) {
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return (Sec->getFlags() & SHF_TLS) && Sec->getType() == SHT_NOBITS;
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}
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template <class ELFT> void LinkerScript<ELFT>::output(InputSection<ELFT> *S) {
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if (!AlreadyOutputIS.insert(S).second)
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return;
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bool IsTbss = isTbss(CurOutSec);
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uintX_t Pos = IsTbss ? Dot + ThreadBssOffset : Dot;
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Pos = alignTo(Pos, S->Alignment);
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S->OutSecOff = Pos - CurOutSec->getVA();
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Pos += S->getSize();
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// Update output section size after adding each section. This is so that
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// SIZEOF works correctly in the case below:
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// .foo { *(.aaa) a = SIZEOF(.foo); *(.bbb) }
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CurOutSec->setSize(Pos - CurOutSec->getVA());
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if (IsTbss)
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ThreadBssOffset = Pos - Dot;
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else
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Dot = Pos;
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}
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template <class ELFT> void LinkerScript<ELFT>::flush() {
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if (!CurOutSec || !AlreadyOutputOS.insert(CurOutSec).second)
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return;
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if (auto *OutSec = dyn_cast<OutputSection<ELFT>>(CurOutSec)) {
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for (InputSection<ELFT> *I : OutSec->Sections)
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output(I);
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} else {
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Dot += CurOutSec->getSize();
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}
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}
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template <class ELFT>
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void LinkerScript<ELFT>::switchTo(OutputSectionBase<ELFT> *Sec) {
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if (CurOutSec == Sec)
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return;
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if (AlreadyOutputOS.count(Sec))
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return;
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flush();
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CurOutSec = Sec;
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Dot = alignTo(Dot, CurOutSec->getAlignment());
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CurOutSec->setVA(isTbss(CurOutSec) ? Dot + ThreadBssOffset : Dot);
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// If neither AT nor AT> is specified for an allocatable section, the linker
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// will set the LMA such that the difference between VMA and LMA for the
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// section is the same as the preceding output section in the same region
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// https://sourceware.org/binutils/docs-2.20/ld/Output-Section-LMA.html
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CurOutSec->setLMAOffset(LMAOffset);
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}
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template <class ELFT> void LinkerScript<ELFT>::process(BaseCommand &Base) {
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// This handles the assignments to symbol or to a location counter (.)
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if (auto *AssignCmd = dyn_cast<SymbolAssignment>(&Base)) {
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if (AssignCmd->Name == ".") {
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// Update to location counter means update to section size.
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Dot = AssignCmd->Expression(Dot);
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CurOutSec->setSize(Dot - CurOutSec->getVA());
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return;
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}
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assignSectionSymbol<ELFT>(AssignCmd, CurOutSec, Dot - CurOutSec->getVA());
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return;
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}
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// Handle BYTE(), SHORT(), LONG(), or QUAD().
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if (auto *DataCmd = dyn_cast<BytesDataCommand>(&Base)) {
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DataCmd->Offset = Dot - CurOutSec->getVA();
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Dot += DataCmd->Size;
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CurOutSec->setSize(Dot - CurOutSec->getVA());
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return;
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}
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// It handles single input section description command,
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// calculates and assigns the offsets for each section and also
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// updates the output section size.
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auto &ICmd = cast<InputSectionDescription>(Base);
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for (InputSectionData *ID : ICmd.Sections) {
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auto *IB = static_cast<InputSectionBase<ELFT> *>(ID);
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switchTo(IB->OutSec);
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if (auto *I = dyn_cast<InputSection<ELFT>>(IB))
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output(I);
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else
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flush();
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}
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}
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template <class ELFT>
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static std::vector<OutputSectionBase<ELFT> *>
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findSections(StringRef Name,
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const std::vector<OutputSectionBase<ELFT> *> &Sections) {
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std::vector<OutputSectionBase<ELFT> *> Ret;
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for (OutputSectionBase<ELFT> *Sec : Sections)
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if (Sec->getName() == Name)
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Ret.push_back(Sec);
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return Ret;
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}
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template <class ELFT>
|
|
void LinkerScript<ELFT>::assignOffsets(OutputSectionCommand *Cmd) {
|
|
if (Cmd->LMAExpr)
|
|
LMAOffset = Cmd->LMAExpr(Dot) - Dot;
|
|
std::vector<OutputSectionBase<ELFT> *> Sections =
|
|
findSections(Cmd->Name, *OutputSections);
|
|
if (Sections.empty())
|
|
return;
|
|
switchTo(Sections[0]);
|
|
// Find the last section output location. We will output orphan sections
|
|
// there so that end symbols point to the correct location.
|
|
auto E = std::find_if(Cmd->Commands.rbegin(), Cmd->Commands.rend(),
|
|
[](const std::unique_ptr<BaseCommand> &Cmd) {
|
|
return !isa<SymbolAssignment>(*Cmd);
|
|
})
|
|
.base();
|
|
for (auto I = Cmd->Commands.begin(); I != E; ++I)
|
|
process(**I);
|
|
for (OutputSectionBase<ELFT> *Base : Sections)
|
|
switchTo(Base);
|
|
flush();
|
|
std::for_each(E, Cmd->Commands.end(),
|
|
[this](std::unique_ptr<BaseCommand> &B) { process(*B.get()); });
|
|
}
|
|
|
|
template <class ELFT> void LinkerScript<ELFT>::adjustSectionsBeforeSorting() {
|
|
// It is common practice to use very generic linker scripts. So for any
|
|
// given run some of the output sections in the script will be empty.
|
|
// We could create corresponding empty output sections, but that would
|
|
// clutter the output.
|
|
// We instead remove trivially empty sections. The bfd linker seems even
|
|
// more aggressive at removing them.
|
|
auto Pos = std::remove_if(
|
|
Opt.Commands.begin(), Opt.Commands.end(),
|
|
[&](const std::unique_ptr<BaseCommand> &Base) {
|
|
auto *Cmd = dyn_cast<OutputSectionCommand>(Base.get());
|
|
if (!Cmd)
|
|
return false;
|
|
std::vector<OutputSectionBase<ELFT> *> Secs =
|
|
findSections(Cmd->Name, *OutputSections);
|
|
if (!Secs.empty())
|
|
return false;
|
|
for (const std::unique_ptr<BaseCommand> &I : Cmd->Commands)
|
|
if (!isa<InputSectionDescription>(I.get()))
|
|
return false;
|
|
return true;
|
|
});
|
|
Opt.Commands.erase(Pos, Opt.Commands.end());
|
|
|
|
// If the output section contains only symbol assignments, create a
|
|
// corresponding output section. The bfd linker seems to only create them if
|
|
// '.' is assigned to, but creating these section should not have any bad
|
|
// consequeces and gives us a section to put the symbol in.
|
|
uintX_t Flags = SHF_ALLOC;
|
|
uint32_t Type = 0;
|
|
for (const std::unique_ptr<BaseCommand> &Base : Opt.Commands) {
|
|
auto *Cmd = dyn_cast<OutputSectionCommand>(Base.get());
|
|
if (!Cmd)
|
|
continue;
|
|
std::vector<OutputSectionBase<ELFT> *> Secs =
|
|
findSections(Cmd->Name, *OutputSections);
|
|
if (!Secs.empty()) {
|
|
Flags = Secs[0]->getFlags();
|
|
Type = Secs[0]->getType();
|
|
continue;
|
|
}
|
|
|
|
auto *OutSec = new OutputSection<ELFT>(Cmd->Name, Type, Flags);
|
|
Out<ELFT>::Pool.emplace_back(OutSec);
|
|
OutputSections->push_back(OutSec);
|
|
}
|
|
}
|
|
|
|
// When placing orphan sections, we want to place them after symbol assignments
|
|
// so that an orphan after
|
|
// begin_foo = .;
|
|
// foo : { *(foo) }
|
|
// end_foo = .;
|
|
// doesn't break the intended meaning of the begin/end symbols.
|
|
// We don't want to go over sections since Writer<ELFT>::sortSections is the
|
|
// one in charge of deciding the order of the sections.
|
|
// We don't want to go over alignments, since doing so in
|
|
// rx_sec : { *(rx_sec) }
|
|
// . = ALIGN(0x1000);
|
|
// /* The RW PT_LOAD starts here*/
|
|
// rw_sec : { *(rw_sec) }
|
|
// would mean that the RW PT_LOAD would become unaligned.
|
|
static bool shouldSkip(const BaseCommand &Cmd) {
|
|
if (isa<OutputSectionCommand>(Cmd))
|
|
return false;
|
|
const auto *Assign = dyn_cast<SymbolAssignment>(&Cmd);
|
|
if (!Assign)
|
|
return true;
|
|
return Assign->Name != ".";
|
|
}
|
|
|
|
template <class ELFT>
|
|
void LinkerScript<ELFT>::assignAddresses(std::vector<PhdrEntry<ELFT>> &Phdrs) {
|
|
// Orphan sections are sections present in the input files which
|
|
// are not explicitly placed into the output file by the linker script.
|
|
// We place orphan sections at end of file.
|
|
// Other linkers places them using some heuristics as described in
|
|
// https://sourceware.org/binutils/docs/ld/Orphan-Sections.html#Orphan-Sections.
|
|
|
|
// The OutputSections are already in the correct order.
|
|
// This loops creates or moves commands as needed so that they are in the
|
|
// correct order.
|
|
int CmdIndex = 0;
|
|
for (OutputSectionBase<ELFT> *Sec : *OutputSections) {
|
|
StringRef Name = Sec->getName();
|
|
|
|
// Find the last spot where we can insert a command and still get the
|
|
// correct result.
|
|
auto CmdIter = Opt.Commands.begin() + CmdIndex;
|
|
auto E = Opt.Commands.end();
|
|
while (CmdIter != E && shouldSkip(**CmdIter)) {
|
|
++CmdIter;
|
|
++CmdIndex;
|
|
}
|
|
|
|
auto Pos =
|
|
std::find_if(CmdIter, E, [&](const std::unique_ptr<BaseCommand> &Base) {
|
|
auto *Cmd = dyn_cast<OutputSectionCommand>(Base.get());
|
|
return Cmd && Cmd->Name == Name;
|
|
});
|
|
if (Pos == E) {
|
|
Opt.Commands.insert(CmdIter,
|
|
llvm::make_unique<OutputSectionCommand>(Name));
|
|
++CmdIndex;
|
|
continue;
|
|
}
|
|
|
|
// Continue from where we found it.
|
|
CmdIndex = (Pos - Opt.Commands.begin()) + 1;
|
|
continue;
|
|
}
|
|
|
|
// Assign addresses as instructed by linker script SECTIONS sub-commands.
|
|
Dot = 0;
|
|
|
|
for (const std::unique_ptr<BaseCommand> &Base : Opt.Commands) {
|
|
if (auto *Cmd = dyn_cast<SymbolAssignment>(Base.get())) {
|
|
if (Cmd->Name == ".") {
|
|
Dot = Cmd->Expression(Dot);
|
|
} else if (Cmd->Sym) {
|
|
cast<DefinedRegular<ELFT>>(Cmd->Sym)->Value = Cmd->Expression(Dot);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
if (auto *Cmd = dyn_cast<AssertCommand>(Base.get())) {
|
|
Cmd->Expression(Dot);
|
|
continue;
|
|
}
|
|
|
|
auto *Cmd = cast<OutputSectionCommand>(Base.get());
|
|
|
|
if (Cmd->AddrExpr)
|
|
Dot = Cmd->AddrExpr(Dot);
|
|
|
|
assignOffsets(Cmd);
|
|
}
|
|
|
|
uintX_t MinVA = std::numeric_limits<uintX_t>::max();
|
|
for (OutputSectionBase<ELFT> *Sec : *OutputSections) {
|
|
if (Sec->getFlags() & SHF_ALLOC)
|
|
MinVA = std::min(MinVA, Sec->getVA());
|
|
else
|
|
Sec->setVA(0);
|
|
}
|
|
|
|
uintX_t HeaderSize = getHeaderSize();
|
|
auto FirstPTLoad =
|
|
std::find_if(Phdrs.begin(), Phdrs.end(), [](const PhdrEntry<ELFT> &E) {
|
|
return E.H.p_type == PT_LOAD;
|
|
});
|
|
if (HeaderSize <= MinVA && FirstPTLoad != Phdrs.end()) {
|
|
// ELF and Program headers need to be right before the first section in
|
|
// memory. Set their addresses accordingly.
|
|
MinVA = alignDown(MinVA - HeaderSize, Target->PageSize);
|
|
Out<ELFT>::ElfHeader->setVA(MinVA);
|
|
Out<ELFT>::ProgramHeaders->setVA(Out<ELFT>::ElfHeader->getSize() + MinVA);
|
|
FirstPTLoad->First = Out<ELFT>::ElfHeader;
|
|
if (!FirstPTLoad->Last)
|
|
FirstPTLoad->Last = Out<ELFT>::ProgramHeaders;
|
|
} else if (!FirstPTLoad->First) {
|
|
// Sometimes the very first PT_LOAD segment can be empty.
|
|
// This happens if (all conditions met):
|
|
// - Linker script is used
|
|
// - First section in ELF image is not RO
|
|
// - Not enough space for program headers.
|
|
// The code below removes empty PT_LOAD segment and updates
|
|
// program headers size.
|
|
Phdrs.erase(FirstPTLoad);
|
|
Out<ELFT>::ProgramHeaders->setSize(sizeof(typename ELFT::Phdr) *
|
|
Phdrs.size());
|
|
}
|
|
}
|
|
|
|
// Creates program headers as instructed by PHDRS linker script command.
|
|
template <class ELFT>
|
|
std::vector<PhdrEntry<ELFT>> LinkerScript<ELFT>::createPhdrs() {
|
|
std::vector<PhdrEntry<ELFT>> Ret;
|
|
|
|
// Process PHDRS and FILEHDR keywords because they are not
|
|
// real output sections and cannot be added in the following loop.
|
|
for (const PhdrsCommand &Cmd : Opt.PhdrsCommands) {
|
|
Ret.emplace_back(Cmd.Type, Cmd.Flags == UINT_MAX ? PF_R : Cmd.Flags);
|
|
PhdrEntry<ELFT> &Phdr = Ret.back();
|
|
|
|
if (Cmd.HasFilehdr)
|
|
Phdr.add(Out<ELFT>::ElfHeader);
|
|
if (Cmd.HasPhdrs)
|
|
Phdr.add(Out<ELFT>::ProgramHeaders);
|
|
|
|
if (Cmd.LMAExpr) {
|
|
Phdr.H.p_paddr = Cmd.LMAExpr(0);
|
|
Phdr.HasLMA = true;
|
|
}
|
|
}
|
|
|
|
// Add output sections to program headers.
|
|
PhdrEntry<ELFT> *Load = nullptr;
|
|
uintX_t Flags = PF_R;
|
|
for (OutputSectionBase<ELFT> *Sec : *OutputSections) {
|
|
if (!(Sec->getFlags() & SHF_ALLOC))
|
|
break;
|
|
|
|
std::vector<size_t> PhdrIds = getPhdrIndices(Sec->getName());
|
|
if (!PhdrIds.empty()) {
|
|
// Assign headers specified by linker script
|
|
for (size_t Id : PhdrIds) {
|
|
Ret[Id].add(Sec);
|
|
if (Opt.PhdrsCommands[Id].Flags == UINT_MAX)
|
|
Ret[Id].H.p_flags |= Sec->getPhdrFlags();
|
|
}
|
|
} else {
|
|
// If we have no load segment or flags've changed then we want new load
|
|
// segment.
|
|
uintX_t NewFlags = Sec->getPhdrFlags();
|
|
if (Load == nullptr || Flags != NewFlags) {
|
|
Load = &*Ret.emplace(Ret.end(), PT_LOAD, NewFlags);
|
|
Flags = NewFlags;
|
|
}
|
|
Load->add(Sec);
|
|
}
|
|
}
|
|
return Ret;
|
|
}
|
|
|
|
template <class ELFT> bool LinkerScript<ELFT>::ignoreInterpSection() {
|
|
// Ignore .interp section in case we have PHDRS specification
|
|
// and PT_INTERP isn't listed.
|
|
return !Opt.PhdrsCommands.empty() &&
|
|
llvm::find_if(Opt.PhdrsCommands, [](const PhdrsCommand &Cmd) {
|
|
return Cmd.Type == PT_INTERP;
|
|
}) == Opt.PhdrsCommands.end();
|
|
}
|
|
|
|
template <class ELFT>
|
|
ArrayRef<uint8_t> LinkerScript<ELFT>::getFiller(StringRef Name) {
|
|
for (const std::unique_ptr<BaseCommand> &Base : Opt.Commands)
|
|
if (auto *Cmd = dyn_cast<OutputSectionCommand>(Base.get()))
|
|
if (Cmd->Name == Name)
|
|
return Cmd->Filler;
|
|
return {};
|
|
}
|
|
|
|
template <class ELFT>
|
|
static void writeInt(uint8_t *Buf, uint64_t Data, uint64_t Size) {
|
|
const endianness E = ELFT::TargetEndianness;
|
|
|
|
switch (Size) {
|
|
case 1:
|
|
*Buf = (uint8_t)Data;
|
|
break;
|
|
case 2:
|
|
write16<E>(Buf, Data);
|
|
break;
|
|
case 4:
|
|
write32<E>(Buf, Data);
|
|
break;
|
|
case 8:
|
|
write64<E>(Buf, Data);
|
|
break;
|
|
default:
|
|
llvm_unreachable("unsupported Size argument");
|
|
}
|
|
}
|
|
|
|
template <class ELFT>
|
|
void LinkerScript<ELFT>::writeDataBytes(StringRef Name, uint8_t *Buf) {
|
|
int I = getSectionIndex(Name);
|
|
if (I == INT_MAX)
|
|
return;
|
|
|
|
OutputSectionCommand *Cmd =
|
|
dyn_cast<OutputSectionCommand>(Opt.Commands[I].get());
|
|
for (const std::unique_ptr<BaseCommand> &Base2 : Cmd->Commands)
|
|
if (auto *DataCmd = dyn_cast<BytesDataCommand>(Base2.get()))
|
|
writeInt<ELFT>(&Buf[DataCmd->Offset], DataCmd->Data, DataCmd->Size);
|
|
}
|
|
|
|
template <class ELFT> bool LinkerScript<ELFT>::hasLMA(StringRef Name) {
|
|
for (const std::unique_ptr<BaseCommand> &Base : Opt.Commands)
|
|
if (auto *Cmd = dyn_cast<OutputSectionCommand>(Base.get()))
|
|
if (Cmd->LMAExpr && Cmd->Name == Name)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
// Returns the index of the given section name in linker script
|
|
// SECTIONS commands. Sections are laid out as the same order as they
|
|
// were in the script. If a given name did not appear in the script,
|
|
// it returns INT_MAX, so that it will be laid out at end of file.
|
|
template <class ELFT> int LinkerScript<ELFT>::getSectionIndex(StringRef Name) {
|
|
int I = 0;
|
|
for (std::unique_ptr<BaseCommand> &Base : Opt.Commands) {
|
|
if (auto *Cmd = dyn_cast<OutputSectionCommand>(Base.get()))
|
|
if (Cmd->Name == Name)
|
|
return I;
|
|
++I;
|
|
}
|
|
return INT_MAX;
|
|
}
|
|
|
|
template <class ELFT> bool LinkerScript<ELFT>::hasPhdrsCommands() {
|
|
return !Opt.PhdrsCommands.empty();
|
|
}
|
|
|
|
template <class ELFT>
|
|
uint64_t LinkerScript<ELFT>::getOutputSectionAddress(StringRef Name) {
|
|
for (OutputSectionBase<ELFT> *Sec : *OutputSections)
|
|
if (Sec->getName() == Name)
|
|
return Sec->getVA();
|
|
error("undefined section " + Name);
|
|
return 0;
|
|
}
|
|
|
|
template <class ELFT>
|
|
uint64_t LinkerScript<ELFT>::getOutputSectionLMA(StringRef Name) {
|
|
for (OutputSectionBase<ELFT> *Sec : *OutputSections)
|
|
if (Sec->getName() == Name)
|
|
return Sec->getLMA();
|
|
error("undefined section " + Name);
|
|
return 0;
|
|
}
|
|
|
|
template <class ELFT>
|
|
uint64_t LinkerScript<ELFT>::getOutputSectionSize(StringRef Name) {
|
|
for (OutputSectionBase<ELFT> *Sec : *OutputSections)
|
|
if (Sec->getName() == Name)
|
|
return Sec->getSize();
|
|
error("undefined section " + Name);
|
|
return 0;
|
|
}
|
|
|
|
template <class ELFT>
|
|
uint64_t LinkerScript<ELFT>::getOutputSectionAlign(StringRef Name) {
|
|
for (OutputSectionBase<ELFT> *Sec : *OutputSections)
|
|
if (Sec->getName() == Name)
|
|
return Sec->getAlignment();
|
|
error("undefined section " + Name);
|
|
return 0;
|
|
}
|
|
|
|
template <class ELFT> uint64_t LinkerScript<ELFT>::getHeaderSize() {
|
|
return elf::getHeaderSize<ELFT>();
|
|
}
|
|
|
|
template <class ELFT> uint64_t LinkerScript<ELFT>::getSymbolValue(StringRef S) {
|
|
if (SymbolBody *B = Symtab<ELFT>::X->find(S))
|
|
return B->getVA<ELFT>();
|
|
error("symbol not found: " + S);
|
|
return 0;
|
|
}
|
|
|
|
template <class ELFT> bool LinkerScript<ELFT>::isDefined(StringRef S) {
|
|
return Symtab<ELFT>::X->find(S) != nullptr;
|
|
}
|
|
|
|
// Returns indices of ELF headers containing specific section, identified
|
|
// by Name. Each index is a zero based number of ELF header listed within
|
|
// PHDRS {} script block.
|
|
template <class ELFT>
|
|
std::vector<size_t> LinkerScript<ELFT>::getPhdrIndices(StringRef SectionName) {
|
|
for (const std::unique_ptr<BaseCommand> &Base : Opt.Commands) {
|
|
auto *Cmd = dyn_cast<OutputSectionCommand>(Base.get());
|
|
if (!Cmd || Cmd->Name != SectionName)
|
|
continue;
|
|
|
|
std::vector<size_t> Ret;
|
|
for (StringRef PhdrName : Cmd->Phdrs)
|
|
Ret.push_back(getPhdrIndex(PhdrName));
|
|
return Ret;
|
|
}
|
|
return {};
|
|
}
|
|
|
|
template <class ELFT>
|
|
size_t LinkerScript<ELFT>::getPhdrIndex(StringRef PhdrName) {
|
|
size_t I = 0;
|
|
for (PhdrsCommand &Cmd : Opt.PhdrsCommands) {
|
|
if (Cmd.Name == PhdrName)
|
|
return I;
|
|
++I;
|
|
}
|
|
error("section header '" + PhdrName + "' is not listed in PHDRS");
|
|
return 0;
|
|
}
|
|
|
|
class elf::ScriptParser : public ScriptParserBase {
|
|
typedef void (ScriptParser::*Handler)();
|
|
|
|
public:
|
|
ScriptParser(StringRef S, bool B) : ScriptParserBase(S), IsUnderSysroot(B) {}
|
|
|
|
void readLinkerScript();
|
|
void readVersionScript();
|
|
|
|
private:
|
|
void addFile(StringRef Path);
|
|
|
|
void readAsNeeded();
|
|
void readEntry();
|
|
void readExtern();
|
|
void readGroup();
|
|
void readInclude();
|
|
void readOutput();
|
|
void readOutputArch();
|
|
void readOutputFormat();
|
|
void readPhdrs();
|
|
void readSearchDir();
|
|
void readSections();
|
|
void readVersion();
|
|
void readVersionScriptCommand();
|
|
|
|
SymbolAssignment *readAssignment(StringRef Name);
|
|
BytesDataCommand *readBytesDataCommand(StringRef Tok);
|
|
std::vector<uint8_t> readFill();
|
|
OutputSectionCommand *readOutputSectionDescription(StringRef OutSec);
|
|
std::vector<uint8_t> readOutputSectionFiller(StringRef Tok);
|
|
std::vector<StringRef> readOutputSectionPhdrs();
|
|
InputSectionDescription *readInputSectionDescription(StringRef Tok);
|
|
Regex readFilePatterns();
|
|
std::vector<SectionPattern> readInputSectionsList();
|
|
InputSectionDescription *readInputSectionRules(StringRef FilePattern);
|
|
unsigned readPhdrType();
|
|
SortSectionPolicy readSortKind();
|
|
SymbolAssignment *readProvideHidden(bool Provide, bool Hidden);
|
|
SymbolAssignment *readProvideOrAssignment(StringRef Tok, bool MakeAbsolute);
|
|
void readSort();
|
|
Expr readAssert();
|
|
|
|
Expr readExpr();
|
|
Expr readExpr1(Expr Lhs, int MinPrec);
|
|
StringRef readParenLiteral();
|
|
Expr readPrimary();
|
|
Expr readTernary(Expr Cond);
|
|
Expr readParenExpr();
|
|
|
|
// For parsing version script.
|
|
void readExtern(std::vector<SymbolVersion> *Globals);
|
|
void readVersionDeclaration(StringRef VerStr);
|
|
void readGlobal(StringRef VerStr);
|
|
void readLocal();
|
|
|
|
ScriptConfiguration &Opt = *ScriptConfig;
|
|
StringSaver Saver = {ScriptConfig->Alloc};
|
|
bool IsUnderSysroot;
|
|
};
|
|
|
|
void ScriptParser::readVersionScript() {
|
|
readVersionScriptCommand();
|
|
if (!atEOF())
|
|
setError("EOF expected, but got " + next());
|
|
}
|
|
|
|
void ScriptParser::readVersionScriptCommand() {
|
|
if (skip("{")) {
|
|
readVersionDeclaration("");
|
|
return;
|
|
}
|
|
|
|
while (!atEOF() && !Error && peek() != "}") {
|
|
StringRef VerStr = next();
|
|
if (VerStr == "{") {
|
|
setError("anonymous version definition is used in "
|
|
"combination with other version definitions");
|
|
return;
|
|
}
|
|
expect("{");
|
|
readVersionDeclaration(VerStr);
|
|
}
|
|
}
|
|
|
|
void ScriptParser::readVersion() {
|
|
expect("{");
|
|
readVersionScriptCommand();
|
|
expect("}");
|
|
}
|
|
|
|
void ScriptParser::readLinkerScript() {
|
|
while (!atEOF()) {
|
|
StringRef Tok = next();
|
|
if (Tok == ";")
|
|
continue;
|
|
|
|
if (Tok == "ASSERT") {
|
|
Opt.Commands.emplace_back(new AssertCommand(readAssert()));
|
|
} else if (Tok == "ENTRY") {
|
|
readEntry();
|
|
} else if (Tok == "EXTERN") {
|
|
readExtern();
|
|
} else if (Tok == "GROUP" || Tok == "INPUT") {
|
|
readGroup();
|
|
} else if (Tok == "INCLUDE") {
|
|
readInclude();
|
|
} else if (Tok == "OUTPUT") {
|
|
readOutput();
|
|
} else if (Tok == "OUTPUT_ARCH") {
|
|
readOutputArch();
|
|
} else if (Tok == "OUTPUT_FORMAT") {
|
|
readOutputFormat();
|
|
} else if (Tok == "PHDRS") {
|
|
readPhdrs();
|
|
} else if (Tok == "SEARCH_DIR") {
|
|
readSearchDir();
|
|
} else if (Tok == "SECTIONS") {
|
|
readSections();
|
|
} else if (Tok == "VERSION") {
|
|
readVersion();
|
|
} else if (SymbolAssignment *Cmd = readProvideOrAssignment(Tok, true)) {
|
|
Opt.Commands.emplace_back(Cmd);
|
|
} else {
|
|
setError("unknown directive: " + Tok);
|
|
}
|
|
}
|
|
}
|
|
|
|
void ScriptParser::addFile(StringRef S) {
|
|
if (IsUnderSysroot && S.startswith("/")) {
|
|
SmallString<128> Path;
|
|
(Config->Sysroot + S).toStringRef(Path);
|
|
if (sys::fs::exists(Path)) {
|
|
Driver->addFile(Saver.save(Path.str()));
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (sys::path::is_absolute(S)) {
|
|
Driver->addFile(S);
|
|
} else if (S.startswith("=")) {
|
|
if (Config->Sysroot.empty())
|
|
Driver->addFile(S.substr(1));
|
|
else
|
|
Driver->addFile(Saver.save(Config->Sysroot + "/" + S.substr(1)));
|
|
} else if (S.startswith("-l")) {
|
|
Driver->addLibrary(S.substr(2));
|
|
} else if (sys::fs::exists(S)) {
|
|
Driver->addFile(S);
|
|
} else {
|
|
std::string Path = findFromSearchPaths(S);
|
|
if (Path.empty())
|
|
setError("unable to find " + S);
|
|
else
|
|
Driver->addFile(Saver.save(Path));
|
|
}
|
|
}
|
|
|
|
void ScriptParser::readAsNeeded() {
|
|
expect("(");
|
|
bool Orig = Config->AsNeeded;
|
|
Config->AsNeeded = true;
|
|
while (!Error && !skip(")"))
|
|
addFile(unquote(next()));
|
|
Config->AsNeeded = Orig;
|
|
}
|
|
|
|
void ScriptParser::readEntry() {
|
|
// -e <symbol> takes predecence over ENTRY(<symbol>).
|
|
expect("(");
|
|
StringRef Tok = next();
|
|
if (Config->Entry.empty())
|
|
Config->Entry = Tok;
|
|
expect(")");
|
|
}
|
|
|
|
void ScriptParser::readExtern() {
|
|
expect("(");
|
|
while (!Error && !skip(")"))
|
|
Config->Undefined.push_back(next());
|
|
}
|
|
|
|
void ScriptParser::readGroup() {
|
|
expect("(");
|
|
while (!Error && !skip(")")) {
|
|
StringRef Tok = next();
|
|
if (Tok == "AS_NEEDED")
|
|
readAsNeeded();
|
|
else
|
|
addFile(unquote(Tok));
|
|
}
|
|
}
|
|
|
|
void ScriptParser::readInclude() {
|
|
StringRef Tok = next();
|
|
auto MBOrErr = MemoryBuffer::getFile(unquote(Tok));
|
|
if (!MBOrErr) {
|
|
setError("cannot open " + Tok);
|
|
return;
|
|
}
|
|
std::unique_ptr<MemoryBuffer> &MB = *MBOrErr;
|
|
StringRef S = Saver.save(MB->getMemBufferRef().getBuffer());
|
|
std::vector<StringRef> V = tokenize(S);
|
|
Tokens.insert(Tokens.begin() + Pos, V.begin(), V.end());
|
|
}
|
|
|
|
void ScriptParser::readOutput() {
|
|
// -o <file> takes predecence over OUTPUT(<file>).
|
|
expect("(");
|
|
StringRef Tok = next();
|
|
if (Config->OutputFile.empty())
|
|
Config->OutputFile = unquote(Tok);
|
|
expect(")");
|
|
}
|
|
|
|
void ScriptParser::readOutputArch() {
|
|
// Error checking only for now.
|
|
expect("(");
|
|
next();
|
|
expect(")");
|
|
}
|
|
|
|
void ScriptParser::readOutputFormat() {
|
|
// Error checking only for now.
|
|
expect("(");
|
|
next();
|
|
StringRef Tok = next();
|
|
if (Tok == ")")
|
|
return;
|
|
if (Tok != ",") {
|
|
setError("unexpected token: " + Tok);
|
|
return;
|
|
}
|
|
next();
|
|
expect(",");
|
|
next();
|
|
expect(")");
|
|
}
|
|
|
|
void ScriptParser::readPhdrs() {
|
|
expect("{");
|
|
while (!Error && !skip("}")) {
|
|
StringRef Tok = next();
|
|
Opt.PhdrsCommands.push_back(
|
|
{Tok, PT_NULL, false, false, UINT_MAX, nullptr});
|
|
PhdrsCommand &PhdrCmd = Opt.PhdrsCommands.back();
|
|
|
|
PhdrCmd.Type = readPhdrType();
|
|
do {
|
|
Tok = next();
|
|
if (Tok == ";")
|
|
break;
|
|
if (Tok == "FILEHDR")
|
|
PhdrCmd.HasFilehdr = true;
|
|
else if (Tok == "PHDRS")
|
|
PhdrCmd.HasPhdrs = true;
|
|
else if (Tok == "AT")
|
|
PhdrCmd.LMAExpr = readParenExpr();
|
|
else if (Tok == "FLAGS") {
|
|
expect("(");
|
|
// Passing 0 for the value of dot is a bit of a hack. It means that
|
|
// we accept expressions like ".|1".
|
|
PhdrCmd.Flags = readExpr()(0);
|
|
expect(")");
|
|
} else
|
|
setError("unexpected header attribute: " + Tok);
|
|
} while (!Error);
|
|
}
|
|
}
|
|
|
|
void ScriptParser::readSearchDir() {
|
|
expect("(");
|
|
StringRef Tok = next();
|
|
if (!Config->Nostdlib)
|
|
Config->SearchPaths.push_back(unquote(Tok));
|
|
expect(")");
|
|
}
|
|
|
|
void ScriptParser::readSections() {
|
|
Opt.HasSections = true;
|
|
expect("{");
|
|
while (!Error && !skip("}")) {
|
|
StringRef Tok = next();
|
|
BaseCommand *Cmd = readProvideOrAssignment(Tok, true);
|
|
if (!Cmd) {
|
|
if (Tok == "ASSERT")
|
|
Cmd = new AssertCommand(readAssert());
|
|
else
|
|
Cmd = readOutputSectionDescription(Tok);
|
|
}
|
|
Opt.Commands.emplace_back(Cmd);
|
|
}
|
|
}
|
|
|
|
static int precedence(StringRef Op) {
|
|
return StringSwitch<int>(Op)
|
|
.Cases("*", "/", 5)
|
|
.Cases("+", "-", 4)
|
|
.Cases("<<", ">>", 3)
|
|
.Cases("<", "<=", ">", ">=", "==", "!=", 2)
|
|
.Cases("&", "|", 1)
|
|
.Default(-1);
|
|
}
|
|
|
|
Regex ScriptParser::readFilePatterns() {
|
|
std::vector<StringRef> V;
|
|
while (!Error && !skip(")"))
|
|
V.push_back(next());
|
|
return compileGlobPatterns(V);
|
|
}
|
|
|
|
SortSectionPolicy ScriptParser::readSortKind() {
|
|
if (skip("SORT") || skip("SORT_BY_NAME"))
|
|
return SortSectionPolicy::Name;
|
|
if (skip("SORT_BY_ALIGNMENT"))
|
|
return SortSectionPolicy::Alignment;
|
|
if (skip("SORT_BY_INIT_PRIORITY"))
|
|
return SortSectionPolicy::Priority;
|
|
if (skip("SORT_NONE"))
|
|
return SortSectionPolicy::None;
|
|
return SortSectionPolicy::Default;
|
|
}
|
|
|
|
// Method reads a list of sequence of excluded files and section globs given in
|
|
// a following form: ((EXCLUDE_FILE(file_pattern+))? section_pattern+)+
|
|
// Example: *(.foo.1 EXCLUDE_FILE (*a.o) .foo.2 EXCLUDE_FILE (*b.o) .foo.3)
|
|
// The semantics of that is next:
|
|
// * Include .foo.1 from every file.
|
|
// * Include .foo.2 from every file but a.o
|
|
// * Include .foo.3 from every file but b.o
|
|
std::vector<SectionPattern> ScriptParser::readInputSectionsList() {
|
|
std::vector<SectionPattern> Ret;
|
|
while (!Error && peek() != ")") {
|
|
Regex ExcludeFileRe;
|
|
if (skip("EXCLUDE_FILE")) {
|
|
expect("(");
|
|
ExcludeFileRe = readFilePatterns();
|
|
}
|
|
|
|
std::vector<StringRef> V;
|
|
while (!Error && peek() != ")" && peek() != "EXCLUDE_FILE")
|
|
V.push_back(next());
|
|
|
|
if (!V.empty())
|
|
Ret.push_back({std::move(ExcludeFileRe), compileGlobPatterns(V)});
|
|
else
|
|
setError("section pattern is expected");
|
|
}
|
|
return Ret;
|
|
}
|
|
|
|
// Section pattern grammar can have complex expressions, for example:
|
|
// *(SORT(.foo.* EXCLUDE_FILE (*file1.o) .bar.*) .bar.* SORT(.zed.*))
|
|
// Generally is a sequence of globs and excludes that may be wrapped in a SORT()
|
|
// commands, like: SORT(glob0) glob1 glob2 SORT(glob4)
|
|
// This methods handles wrapping sequences of excluded files and section globs
|
|
// into SORT() if that needed and reads them all.
|
|
InputSectionDescription *
|
|
ScriptParser::readInputSectionRules(StringRef FilePattern) {
|
|
auto *Cmd = new InputSectionDescription(FilePattern);
|
|
expect("(");
|
|
while (!HasError && !skip(")")) {
|
|
SortSectionPolicy Outer = readSortKind();
|
|
SortSectionPolicy Inner = SortSectionPolicy::Default;
|
|
std::vector<SectionPattern> V;
|
|
if (Outer != SortSectionPolicy::Default) {
|
|
expect("(");
|
|
Inner = readSortKind();
|
|
if (Inner != SortSectionPolicy::Default) {
|
|
expect("(");
|
|
V = readInputSectionsList();
|
|
expect(")");
|
|
} else {
|
|
V = readInputSectionsList();
|
|
}
|
|
expect(")");
|
|
} else {
|
|
V = readInputSectionsList();
|
|
}
|
|
|
|
for (SectionPattern &Pat : V) {
|
|
Pat.SortInner = Inner;
|
|
Pat.SortOuter = Outer;
|
|
}
|
|
|
|
std::move(V.begin(), V.end(), std::back_inserter(Cmd->SectionPatterns));
|
|
}
|
|
return Cmd;
|
|
}
|
|
|
|
InputSectionDescription *
|
|
ScriptParser::readInputSectionDescription(StringRef Tok) {
|
|
// Input section wildcard can be surrounded by KEEP.
|
|
// https://sourceware.org/binutils/docs/ld/Input-Section-Keep.html#Input-Section-Keep
|
|
if (Tok == "KEEP") {
|
|
expect("(");
|
|
StringRef FilePattern = next();
|
|
InputSectionDescription *Cmd = readInputSectionRules(FilePattern);
|
|
expect(")");
|
|
Opt.KeptSections.push_back(Cmd);
|
|
return Cmd;
|
|
}
|
|
return readInputSectionRules(Tok);
|
|
}
|
|
|
|
void ScriptParser::readSort() {
|
|
expect("(");
|
|
expect("CONSTRUCTORS");
|
|
expect(")");
|
|
}
|
|
|
|
Expr ScriptParser::readAssert() {
|
|
expect("(");
|
|
Expr E = readExpr();
|
|
expect(",");
|
|
StringRef Msg = unquote(next());
|
|
expect(")");
|
|
return [=](uint64_t Dot) {
|
|
uint64_t V = E(Dot);
|
|
if (!V)
|
|
error(Msg);
|
|
return V;
|
|
};
|
|
}
|
|
|
|
// Reads a FILL(expr) command. We handle the FILL command as an
|
|
// alias for =fillexp section attribute, which is different from
|
|
// what GNU linkers do.
|
|
// https://sourceware.org/binutils/docs/ld/Output-Section-Data.html
|
|
std::vector<uint8_t> ScriptParser::readFill() {
|
|
expect("(");
|
|
std::vector<uint8_t> V = readOutputSectionFiller(next());
|
|
expect(")");
|
|
expect(";");
|
|
return V;
|
|
}
|
|
|
|
OutputSectionCommand *
|
|
ScriptParser::readOutputSectionDescription(StringRef OutSec) {
|
|
OutputSectionCommand *Cmd = new OutputSectionCommand(OutSec);
|
|
|
|
// Read an address expression.
|
|
// https://sourceware.org/binutils/docs/ld/Output-Section-Address.html#Output-Section-Address
|
|
if (peek() != ":")
|
|
Cmd->AddrExpr = readExpr();
|
|
|
|
expect(":");
|
|
|
|
if (skip("AT"))
|
|
Cmd->LMAExpr = readParenExpr();
|
|
if (skip("ALIGN"))
|
|
Cmd->AlignExpr = readParenExpr();
|
|
if (skip("SUBALIGN"))
|
|
Cmd->SubalignExpr = readParenExpr();
|
|
|
|
// Parse constraints.
|
|
if (skip("ONLY_IF_RO"))
|
|
Cmd->Constraint = ConstraintKind::ReadOnly;
|
|
if (skip("ONLY_IF_RW"))
|
|
Cmd->Constraint = ConstraintKind::ReadWrite;
|
|
expect("{");
|
|
|
|
while (!Error && !skip("}")) {
|
|
StringRef Tok = next();
|
|
if (SymbolAssignment *Assignment = readProvideOrAssignment(Tok, false))
|
|
Cmd->Commands.emplace_back(Assignment);
|
|
else if (BytesDataCommand *Data = readBytesDataCommand(Tok))
|
|
Cmd->Commands.emplace_back(Data);
|
|
else if (Tok == "FILL")
|
|
Cmd->Filler = readFill();
|
|
else if (Tok == "SORT")
|
|
readSort();
|
|
else if (peek() == "(")
|
|
Cmd->Commands.emplace_back(readInputSectionDescription(Tok));
|
|
else
|
|
setError("unknown command " + Tok);
|
|
}
|
|
Cmd->Phdrs = readOutputSectionPhdrs();
|
|
|
|
if (skip("="))
|
|
Cmd->Filler = readOutputSectionFiller(next());
|
|
else if (peek().startswith("="))
|
|
Cmd->Filler = readOutputSectionFiller(next().drop_front());
|
|
|
|
return Cmd;
|
|
}
|
|
|
|
// Read "=<number>" where <number> is an octal/decimal/hexadecimal number.
|
|
// https://sourceware.org/binutils/docs/ld/Output-Section-Fill.html
|
|
//
|
|
// ld.gold is not fully compatible with ld.bfd. ld.bfd handles
|
|
// hexstrings as blobs of arbitrary sizes, while ld.gold handles them
|
|
// as 32-bit big-endian values. We will do the same as ld.gold does
|
|
// because it's simpler than what ld.bfd does.
|
|
std::vector<uint8_t> ScriptParser::readOutputSectionFiller(StringRef Tok) {
|
|
uint32_t V;
|
|
if (Tok.getAsInteger(0, V)) {
|
|
setError("invalid filler expression: " + Tok);
|
|
return {};
|
|
}
|
|
return {uint8_t(V >> 24), uint8_t(V >> 16), uint8_t(V >> 8), uint8_t(V)};
|
|
}
|
|
|
|
SymbolAssignment *ScriptParser::readProvideHidden(bool Provide, bool Hidden) {
|
|
expect("(");
|
|
SymbolAssignment *Cmd = readAssignment(next());
|
|
Cmd->Provide = Provide;
|
|
Cmd->Hidden = Hidden;
|
|
expect(")");
|
|
expect(";");
|
|
return Cmd;
|
|
}
|
|
|
|
SymbolAssignment *ScriptParser::readProvideOrAssignment(StringRef Tok,
|
|
bool MakeAbsolute) {
|
|
SymbolAssignment *Cmd = nullptr;
|
|
if (peek() == "=" || peek() == "+=") {
|
|
Cmd = readAssignment(Tok);
|
|
expect(";");
|
|
} else if (Tok == "PROVIDE") {
|
|
Cmd = readProvideHidden(true, false);
|
|
} else if (Tok == "HIDDEN") {
|
|
Cmd = readProvideHidden(false, true);
|
|
} else if (Tok == "PROVIDE_HIDDEN") {
|
|
Cmd = readProvideHidden(true, true);
|
|
}
|
|
if (Cmd && MakeAbsolute)
|
|
Cmd->IsAbsolute = true;
|
|
return Cmd;
|
|
}
|
|
|
|
static uint64_t getSymbolValue(StringRef S, uint64_t Dot) {
|
|
if (S == ".")
|
|
return Dot;
|
|
return ScriptBase->getSymbolValue(S);
|
|
}
|
|
|
|
SymbolAssignment *ScriptParser::readAssignment(StringRef Name) {
|
|
StringRef Op = next();
|
|
bool IsAbsolute = false;
|
|
Expr E;
|
|
assert(Op == "=" || Op == "+=");
|
|
if (skip("ABSOLUTE")) {
|
|
E = readParenExpr();
|
|
IsAbsolute = true;
|
|
} else {
|
|
E = readExpr();
|
|
}
|
|
if (Op == "+=")
|
|
E = [=](uint64_t Dot) { return getSymbolValue(Name, Dot) + E(Dot); };
|
|
return new SymbolAssignment(Name, E, IsAbsolute);
|
|
}
|
|
|
|
// This is an operator-precedence parser to parse a linker
|
|
// script expression.
|
|
Expr ScriptParser::readExpr() { return readExpr1(readPrimary(), 0); }
|
|
|
|
static Expr combine(StringRef Op, Expr L, Expr R) {
|
|
if (Op == "*")
|
|
return [=](uint64_t Dot) { return L(Dot) * R(Dot); };
|
|
if (Op == "/") {
|
|
return [=](uint64_t Dot) -> uint64_t {
|
|
uint64_t RHS = R(Dot);
|
|
if (RHS == 0) {
|
|
error("division by zero");
|
|
return 0;
|
|
}
|
|
return L(Dot) / RHS;
|
|
};
|
|
}
|
|
if (Op == "+")
|
|
return [=](uint64_t Dot) { return L(Dot) + R(Dot); };
|
|
if (Op == "-")
|
|
return [=](uint64_t Dot) { return L(Dot) - R(Dot); };
|
|
if (Op == "<<")
|
|
return [=](uint64_t Dot) { return L(Dot) << R(Dot); };
|
|
if (Op == ">>")
|
|
return [=](uint64_t Dot) { return L(Dot) >> R(Dot); };
|
|
if (Op == "<")
|
|
return [=](uint64_t Dot) { return L(Dot) < R(Dot); };
|
|
if (Op == ">")
|
|
return [=](uint64_t Dot) { return L(Dot) > R(Dot); };
|
|
if (Op == ">=")
|
|
return [=](uint64_t Dot) { return L(Dot) >= R(Dot); };
|
|
if (Op == "<=")
|
|
return [=](uint64_t Dot) { return L(Dot) <= R(Dot); };
|
|
if (Op == "==")
|
|
return [=](uint64_t Dot) { return L(Dot) == R(Dot); };
|
|
if (Op == "!=")
|
|
return [=](uint64_t Dot) { return L(Dot) != R(Dot); };
|
|
if (Op == "&")
|
|
return [=](uint64_t Dot) { return L(Dot) & R(Dot); };
|
|
if (Op == "|")
|
|
return [=](uint64_t Dot) { return L(Dot) | R(Dot); };
|
|
llvm_unreachable("invalid operator");
|
|
}
|
|
|
|
// This is a part of the operator-precedence parser. This function
|
|
// assumes that the remaining token stream starts with an operator.
|
|
Expr ScriptParser::readExpr1(Expr Lhs, int MinPrec) {
|
|
while (!atEOF() && !Error) {
|
|
// Read an operator and an expression.
|
|
StringRef Op1 = peek();
|
|
if (Op1 == "?")
|
|
return readTernary(Lhs);
|
|
if (precedence(Op1) < MinPrec)
|
|
break;
|
|
next();
|
|
Expr Rhs = readPrimary();
|
|
|
|
// Evaluate the remaining part of the expression first if the
|
|
// next operator has greater precedence than the previous one.
|
|
// For example, if we have read "+" and "3", and if the next
|
|
// operator is "*", then we'll evaluate 3 * ... part first.
|
|
while (!atEOF()) {
|
|
StringRef Op2 = peek();
|
|
if (precedence(Op2) <= precedence(Op1))
|
|
break;
|
|
Rhs = readExpr1(Rhs, precedence(Op2));
|
|
}
|
|
|
|
Lhs = combine(Op1, Lhs, Rhs);
|
|
}
|
|
return Lhs;
|
|
}
|
|
|
|
uint64_t static getConstant(StringRef S) {
|
|
if (S == "COMMONPAGESIZE")
|
|
return Target->PageSize;
|
|
if (S == "MAXPAGESIZE")
|
|
return Config->MaxPageSize;
|
|
error("unknown constant: " + S);
|
|
return 0;
|
|
}
|
|
|
|
// Parses Tok as an integer. Returns true if successful.
|
|
// It recognizes hexadecimal (prefixed with "0x" or suffixed with "H")
|
|
// and decimal numbers. Decimal numbers may have "K" (kilo) or
|
|
// "M" (mega) prefixes.
|
|
static bool readInteger(StringRef Tok, uint64_t &Result) {
|
|
if (Tok.startswith("-")) {
|
|
if (!readInteger(Tok.substr(1), Result))
|
|
return false;
|
|
Result = -Result;
|
|
return true;
|
|
}
|
|
if (Tok.startswith_lower("0x"))
|
|
return !Tok.substr(2).getAsInteger(16, Result);
|
|
if (Tok.endswith_lower("H"))
|
|
return !Tok.drop_back().getAsInteger(16, Result);
|
|
|
|
int Suffix = 1;
|
|
if (Tok.endswith_lower("K")) {
|
|
Suffix = 1024;
|
|
Tok = Tok.drop_back();
|
|
} else if (Tok.endswith_lower("M")) {
|
|
Suffix = 1024 * 1024;
|
|
Tok = Tok.drop_back();
|
|
}
|
|
if (Tok.getAsInteger(10, Result))
|
|
return false;
|
|
Result *= Suffix;
|
|
return true;
|
|
}
|
|
|
|
BytesDataCommand *ScriptParser::readBytesDataCommand(StringRef Tok) {
|
|
int Size = StringSwitch<unsigned>(Tok)
|
|
.Case("BYTE", 1)
|
|
.Case("SHORT", 2)
|
|
.Case("LONG", 4)
|
|
.Case("QUAD", 8)
|
|
.Default(-1);
|
|
if (Size == -1)
|
|
return nullptr;
|
|
|
|
expect("(");
|
|
uint64_t Val = 0;
|
|
StringRef S = next();
|
|
if (!readInteger(S, Val))
|
|
setError("unexpected value: " + S);
|
|
expect(")");
|
|
return new BytesDataCommand(Val, Size);
|
|
}
|
|
|
|
StringRef ScriptParser::readParenLiteral() {
|
|
expect("(");
|
|
StringRef Tok = next();
|
|
expect(")");
|
|
return Tok;
|
|
}
|
|
|
|
Expr ScriptParser::readPrimary() {
|
|
if (peek() == "(")
|
|
return readParenExpr();
|
|
|
|
StringRef Tok = next();
|
|
|
|
if (Tok == "~") {
|
|
Expr E = readPrimary();
|
|
return [=](uint64_t Dot) { return ~E(Dot); };
|
|
}
|
|
if (Tok == "-") {
|
|
Expr E = readPrimary();
|
|
return [=](uint64_t Dot) { return -E(Dot); };
|
|
}
|
|
|
|
// Built-in functions are parsed here.
|
|
// https://sourceware.org/binutils/docs/ld/Builtin-Functions.html.
|
|
if (Tok == "ADDR") {
|
|
StringRef Name = readParenLiteral();
|
|
return
|
|
[=](uint64_t Dot) { return ScriptBase->getOutputSectionAddress(Name); };
|
|
}
|
|
if (Tok == "LOADADDR") {
|
|
StringRef Name = readParenLiteral();
|
|
return [=](uint64_t Dot) { return ScriptBase->getOutputSectionLMA(Name); };
|
|
}
|
|
if (Tok == "ASSERT")
|
|
return readAssert();
|
|
if (Tok == "ALIGN") {
|
|
Expr E = readParenExpr();
|
|
return [=](uint64_t Dot) { return alignTo(Dot, E(Dot)); };
|
|
}
|
|
if (Tok == "CONSTANT") {
|
|
StringRef Name = readParenLiteral();
|
|
return [=](uint64_t Dot) { return getConstant(Name); };
|
|
}
|
|
if (Tok == "DEFINED") {
|
|
expect("(");
|
|
StringRef Tok = next();
|
|
expect(")");
|
|
return [=](uint64_t Dot) { return ScriptBase->isDefined(Tok) ? 1 : 0; };
|
|
}
|
|
if (Tok == "SEGMENT_START") {
|
|
expect("(");
|
|
next();
|
|
expect(",");
|
|
Expr E = readExpr();
|
|
expect(")");
|
|
return [=](uint64_t Dot) { return E(Dot); };
|
|
}
|
|
if (Tok == "DATA_SEGMENT_ALIGN") {
|
|
expect("(");
|
|
Expr E = readExpr();
|
|
expect(",");
|
|
readExpr();
|
|
expect(")");
|
|
return [=](uint64_t Dot) { return alignTo(Dot, E(Dot)); };
|
|
}
|
|
if (Tok == "DATA_SEGMENT_END") {
|
|
expect("(");
|
|
expect(".");
|
|
expect(")");
|
|
return [](uint64_t Dot) { return Dot; };
|
|
}
|
|
// GNU linkers implements more complicated logic to handle
|
|
// DATA_SEGMENT_RELRO_END. We instead ignore the arguments and just align to
|
|
// the next page boundary for simplicity.
|
|
if (Tok == "DATA_SEGMENT_RELRO_END") {
|
|
expect("(");
|
|
readExpr();
|
|
expect(",");
|
|
readExpr();
|
|
expect(")");
|
|
return [](uint64_t Dot) { return alignTo(Dot, Target->PageSize); };
|
|
}
|
|
if (Tok == "SIZEOF") {
|
|
StringRef Name = readParenLiteral();
|
|
return [=](uint64_t Dot) { return ScriptBase->getOutputSectionSize(Name); };
|
|
}
|
|
if (Tok == "ALIGNOF") {
|
|
StringRef Name = readParenLiteral();
|
|
return
|
|
[=](uint64_t Dot) { return ScriptBase->getOutputSectionAlign(Name); };
|
|
}
|
|
if (Tok == "SIZEOF_HEADERS")
|
|
return [=](uint64_t Dot) { return ScriptBase->getHeaderSize(); };
|
|
|
|
// Tok is a literal number.
|
|
uint64_t V;
|
|
if (readInteger(Tok, V))
|
|
return [=](uint64_t Dot) { return V; };
|
|
|
|
// Tok is a symbol name.
|
|
if (Tok != "." && !isValidCIdentifier(Tok))
|
|
setError("malformed number: " + Tok);
|
|
return [=](uint64_t Dot) { return getSymbolValue(Tok, Dot); };
|
|
}
|
|
|
|
Expr ScriptParser::readTernary(Expr Cond) {
|
|
next();
|
|
Expr L = readExpr();
|
|
expect(":");
|
|
Expr R = readExpr();
|
|
return [=](uint64_t Dot) { return Cond(Dot) ? L(Dot) : R(Dot); };
|
|
}
|
|
|
|
Expr ScriptParser::readParenExpr() {
|
|
expect("(");
|
|
Expr E = readExpr();
|
|
expect(")");
|
|
return E;
|
|
}
|
|
|
|
std::vector<StringRef> ScriptParser::readOutputSectionPhdrs() {
|
|
std::vector<StringRef> Phdrs;
|
|
while (!Error && peek().startswith(":")) {
|
|
StringRef Tok = next();
|
|
Tok = (Tok.size() == 1) ? next() : Tok.substr(1);
|
|
if (Tok.empty()) {
|
|
setError("section header name is empty");
|
|
break;
|
|
}
|
|
Phdrs.push_back(Tok);
|
|
}
|
|
return Phdrs;
|
|
}
|
|
|
|
unsigned ScriptParser::readPhdrType() {
|
|
StringRef Tok = next();
|
|
unsigned Ret = StringSwitch<unsigned>(Tok)
|
|
.Case("PT_NULL", PT_NULL)
|
|
.Case("PT_LOAD", PT_LOAD)
|
|
.Case("PT_DYNAMIC", PT_DYNAMIC)
|
|
.Case("PT_INTERP", PT_INTERP)
|
|
.Case("PT_NOTE", PT_NOTE)
|
|
.Case("PT_SHLIB", PT_SHLIB)
|
|
.Case("PT_PHDR", PT_PHDR)
|
|
.Case("PT_TLS", PT_TLS)
|
|
.Case("PT_GNU_EH_FRAME", PT_GNU_EH_FRAME)
|
|
.Case("PT_GNU_STACK", PT_GNU_STACK)
|
|
.Case("PT_GNU_RELRO", PT_GNU_RELRO)
|
|
.Default(-1);
|
|
|
|
if (Ret == (unsigned)-1) {
|
|
setError("invalid program header type: " + Tok);
|
|
return PT_NULL;
|
|
}
|
|
return Ret;
|
|
}
|
|
|
|
void ScriptParser::readVersionDeclaration(StringRef VerStr) {
|
|
// Identifiers start at 2 because 0 and 1 are reserved
|
|
// for VER_NDX_LOCAL and VER_NDX_GLOBAL constants.
|
|
size_t VersionId = Config->VersionDefinitions.size() + 2;
|
|
Config->VersionDefinitions.push_back({VerStr, VersionId});
|
|
|
|
if (skip("global:") || peek() != "local:")
|
|
readGlobal(VerStr);
|
|
if (skip("local:"))
|
|
readLocal();
|
|
expect("}");
|
|
|
|
// Each version may have a parent version. For example, "Ver2" defined as
|
|
// "Ver2 { global: foo; local: *; } Ver1;" has "Ver1" as a parent. This
|
|
// version hierarchy is, probably against your instinct, purely for human; the
|
|
// runtime doesn't care about them at all. In LLD, we simply skip the token.
|
|
if (!VerStr.empty() && peek() != ";")
|
|
next();
|
|
expect(";");
|
|
}
|
|
|
|
void ScriptParser::readLocal() {
|
|
Config->DefaultSymbolVersion = VER_NDX_LOCAL;
|
|
expect("*");
|
|
expect(";");
|
|
}
|
|
|
|
void ScriptParser::readExtern(std::vector<SymbolVersion> *Globals) {
|
|
expect("\"C++\"");
|
|
expect("{");
|
|
|
|
for (;;) {
|
|
if (peek() == "}" || Error)
|
|
break;
|
|
bool HasWildcard = !peek().startswith("\"") && hasWildcard(peek());
|
|
Globals->push_back({unquote(next()), true, HasWildcard});
|
|
expect(";");
|
|
}
|
|
|
|
expect("}");
|
|
expect(";");
|
|
}
|
|
|
|
void ScriptParser::readGlobal(StringRef VerStr) {
|
|
std::vector<SymbolVersion> *Globals;
|
|
if (VerStr.empty())
|
|
Globals = &Config->VersionScriptGlobals;
|
|
else
|
|
Globals = &Config->VersionDefinitions.back().Globals;
|
|
|
|
for (;;) {
|
|
if (skip("extern"))
|
|
readExtern(Globals);
|
|
|
|
StringRef Cur = peek();
|
|
if (Cur == "}" || Cur == "local:" || Error)
|
|
return;
|
|
next();
|
|
Globals->push_back({unquote(Cur), false, hasWildcard(Cur)});
|
|
expect(";");
|
|
}
|
|
}
|
|
|
|
static bool isUnderSysroot(StringRef Path) {
|
|
if (Config->Sysroot == "")
|
|
return false;
|
|
for (; !Path.empty(); Path = sys::path::parent_path(Path))
|
|
if (sys::fs::equivalent(Config->Sysroot, Path))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
void elf::readLinkerScript(MemoryBufferRef MB) {
|
|
StringRef Path = MB.getBufferIdentifier();
|
|
ScriptParser(MB.getBuffer(), isUnderSysroot(Path)).readLinkerScript();
|
|
}
|
|
|
|
void elf::readVersionScript(MemoryBufferRef MB) {
|
|
ScriptParser(MB.getBuffer(), false).readVersionScript();
|
|
}
|
|
|
|
template class elf::LinkerScript<ELF32LE>;
|
|
template class elf::LinkerScript<ELF32BE>;
|
|
template class elf::LinkerScript<ELF64LE>;
|
|
template class elf::LinkerScript<ELF64BE>;
|