Apply upstream lld fix for compressed input sections on BE targets

Merge commit c6ebc651b6fa from llvm git (by Simon Atanasyan):

  [LLD] Support compressed input sections on big-endian targets

  This patch enables compressed input sections on big-endian targets by
  checking the target endianness and selecting an appropriate `Chdr`
  structure.

  Fixes PR51369

  Differential Revision: https://reviews.llvm.org/D107635

Reported by:	emaste
MFC after:	3 days
This commit is contained in:
Dimitry Andric 2021-08-07 13:14:11 +02:00
parent b30e7cb7fa
commit d69d07569e
2 changed files with 21 additions and 27 deletions

View File

@ -88,7 +88,22 @@ InputSectionBase::InputSectionBase(InputFile *file, uint64_t flags,
if (!zlib::isAvailable())
error(toString(file) + ": contains a compressed section, " +
"but zlib is not available");
parseCompressedHeader();
switch (config->ekind) {
case ELF32LEKind:
parseCompressedHeader<ELF32LE>();
break;
case ELF32BEKind:
parseCompressedHeader<ELF32BE>();
break;
case ELF64LEKind:
parseCompressedHeader<ELF64LE>();
break;
case ELF64BEKind:
parseCompressedHeader<ELF64BE>();
break;
default:
llvm_unreachable("unknown ELFT");
}
}
}
@ -210,10 +225,7 @@ OutputSection *SectionBase::getOutputSection() {
// When a section is compressed, `rawData` consists with a header followed
// by zlib-compressed data. This function parses a header to initialize
// `uncompressedSize` member and remove the header from `rawData`.
void InputSectionBase::parseCompressedHeader() {
using Chdr64 = typename ELF64LE::Chdr;
using Chdr32 = typename ELF32LE::Chdr;
template <typename ELFT> void InputSectionBase::parseCompressedHeader() {
// Old-style header
if (name.startswith(".zdebug")) {
if (!toStringRef(rawData).startswith("ZLIB")) {
@ -239,32 +251,13 @@ void InputSectionBase::parseCompressedHeader() {
assert(flags & SHF_COMPRESSED);
flags &= ~(uint64_t)SHF_COMPRESSED;
// New-style 64-bit header
if (config->is64) {
if (rawData.size() < sizeof(Chdr64)) {
error(toString(this) + ": corrupted compressed section");
return;
}
auto *hdr = reinterpret_cast<const Chdr64 *>(rawData.data());
if (hdr->ch_type != ELFCOMPRESS_ZLIB) {
error(toString(this) + ": unsupported compression type");
return;
}
uncompressedSize = hdr->ch_size;
alignment = std::max<uint32_t>(hdr->ch_addralign, 1);
rawData = rawData.slice(sizeof(*hdr));
return;
}
// New-style 32-bit header
if (rawData.size() < sizeof(Chdr32)) {
// New-style header
if (rawData.size() < sizeof(typename ELFT::Chdr)) {
error(toString(this) + ": corrupted compressed section");
return;
}
auto *hdr = reinterpret_cast<const Chdr32 *>(rawData.data());
auto *hdr = reinterpret_cast<const typename ELFT::Chdr *>(rawData.data());
if (hdr->ch_type != ELFCOMPRESS_ZLIB) {
error(toString(this) + ": unsupported compression type");
return;

View File

@ -238,6 +238,7 @@ class InputSectionBase : public SectionBase {
}
protected:
template <typename ELFT>
void parseCompressedHeader();
void uncompress() const;