121 lines
3.9 KiB
C++
121 lines
3.9 KiB
C++
//===- lib/ReaderWriter/ELF/ARM/ARMELFWriters.h ---------------------------===//
|
|
//
|
|
// The LLVM Linker
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
#ifndef LLD_READER_WRITER_ELF_ARM_ARM_ELF_WRITERS_H
|
|
#define LLD_READER_WRITER_ELF_ARM_ARM_ELF_WRITERS_H
|
|
|
|
#include "ARMLinkingContext.h"
|
|
#include "ARMSymbolTable.h"
|
|
#include "llvm/Support/ELF.h"
|
|
|
|
namespace lld {
|
|
namespace elf {
|
|
|
|
template <class WriterT> class ARMELFWriter : public WriterT {
|
|
public:
|
|
ARMELFWriter(ARMLinkingContext &ctx, TargetLayout<ELF32LE> &layout);
|
|
|
|
void finalizeDefaultAtomValues() override;
|
|
|
|
/// \brief Create symbol table.
|
|
unique_bump_ptr<SymbolTable<ELF32LE>> createSymbolTable() override;
|
|
|
|
// Setup the ELF header.
|
|
std::error_code setELFHeader() override;
|
|
|
|
protected:
|
|
static const char *gotSymbol;
|
|
static const char *dynamicSymbol;
|
|
|
|
private:
|
|
ARMLinkingContext &_ctx;
|
|
TargetLayout<ELF32LE> &_armLayout;
|
|
};
|
|
|
|
template <class WriterT>
|
|
const char *ARMELFWriter<WriterT>::gotSymbol = "_GLOBAL_OFFSET_TABLE_";
|
|
template <class WriterT>
|
|
const char *ARMELFWriter<WriterT>::dynamicSymbol = "_DYNAMIC";
|
|
|
|
template <class WriterT>
|
|
ARMELFWriter<WriterT>::ARMELFWriter(ARMLinkingContext &ctx,
|
|
TargetLayout<ELF32LE> &layout)
|
|
: WriterT(ctx, layout), _ctx(ctx), _armLayout(layout) {}
|
|
|
|
template <class WriterT>
|
|
void ARMELFWriter<WriterT>::finalizeDefaultAtomValues() {
|
|
// Finalize the atom values that are part of the parent.
|
|
WriterT::finalizeDefaultAtomValues();
|
|
|
|
if (auto *gotAtom = _armLayout.findAbsoluteAtom(gotSymbol)) {
|
|
if (auto gotpltSection = _armLayout.findOutputSection(".got.plt"))
|
|
gotAtom->_virtualAddr = gotpltSection->virtualAddr();
|
|
else if (auto gotSection = _armLayout.findOutputSection(".got"))
|
|
gotAtom->_virtualAddr = gotSection->virtualAddr();
|
|
else
|
|
gotAtom->_virtualAddr = 0;
|
|
}
|
|
|
|
if (auto *dynamicAtom = _armLayout.findAbsoluteAtom(dynamicSymbol)) {
|
|
if (auto dynamicSection = _armLayout.findOutputSection(".dynamic"))
|
|
dynamicAtom->_virtualAddr = dynamicSection->virtualAddr();
|
|
else
|
|
dynamicAtom->_virtualAddr = 0;
|
|
}
|
|
|
|
// Set required by gcc libc __ehdr_start symbol with pointer to ELF header
|
|
if (auto ehdr = _armLayout.findAbsoluteAtom("__ehdr_start"))
|
|
ehdr->_virtualAddr = this->_elfHeader->virtualAddr();
|
|
|
|
// Set required by gcc libc symbols __exidx_start/__exidx_end
|
|
this->updateScopeAtomValues("exidx", ".ARM.exidx");
|
|
}
|
|
|
|
template <class WriterT>
|
|
unique_bump_ptr<SymbolTable<ELF32LE>>
|
|
ARMELFWriter<WriterT>::createSymbolTable() {
|
|
return unique_bump_ptr<SymbolTable<ELF32LE>>(new (this->_alloc)
|
|
ARMSymbolTable(_ctx));
|
|
}
|
|
|
|
template <class WriterT> std::error_code ARMELFWriter<WriterT>::setELFHeader() {
|
|
if (std::error_code ec = WriterT::setELFHeader())
|
|
return ec;
|
|
|
|
// Set ARM-specific flags.
|
|
this->_elfHeader->e_flags(llvm::ELF::EF_ARM_EABI_VER5 |
|
|
llvm::ELF::EF_ARM_VFP_FLOAT);
|
|
|
|
StringRef entryName = _ctx.entrySymbolName();
|
|
if (const AtomLayout *al = _armLayout.findAtomLayoutByName(entryName)) {
|
|
if (const auto *ea = dyn_cast<DefinedAtom>(al->_atom)) {
|
|
switch (ea->codeModel()) {
|
|
case DefinedAtom::codeNA:
|
|
if (al->_virtualAddr & 0x3) {
|
|
llvm::report_fatal_error(
|
|
"Two least bits must be zero for ARM entry point");
|
|
}
|
|
break;
|
|
case DefinedAtom::codeARMThumb:
|
|
// Fixup entry point for Thumb code.
|
|
this->_elfHeader->e_entry(al->_virtualAddr | 0x1);
|
|
break;
|
|
default:
|
|
llvm_unreachable("Wrong code model of entry point atom");
|
|
}
|
|
}
|
|
}
|
|
|
|
return std::error_code();
|
|
}
|
|
|
|
} // namespace elf
|
|
} // namespace lld
|
|
|
|
#endif // LLD_READER_WRITER_ELF_ARM_ARM_ELF_WRITERS_H
|