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[ELF] - Handle EhInputSection Live bit in MarkLive.cpp 

Since MarkLive.cpp is the place where we set Live flags for
other sections, it looks correct to do that there.
Benefit is that we stop spreading GC logic outsize of MarkLive.cpp.

Differential revision: https://reviews.llvm.org/D40454

llvm-svn: 319435
This commit is contained in:
George Rimar 2017-11-30 14:01:06 +00:00
parent db7e77047c
commit 2e610cd470
2 changed files with 9 additions and 10 deletions
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7
lld/ELF/InputSection.cpp
View File

@ -808,12 +808,7 @@ template <class ELFT>
EhInputSection::EhInputSection(ObjFile<ELFT> *F,
const typename ELFT::Shdr *Header,
StringRef Name)
: InputSectionBase(F, Header, Name, InputSectionBase::EHFrame) {
// Mark .eh_frame sections as live by default because there are
// usually no relocations that point to .eh_frames. Otherwise,
// the garbage collector would drop all .eh_frame sections.
this->Live = true;
}
: InputSectionBase(F, Header, Name, InputSectionBase::EHFrame) {}
SyntheticSection *EhInputSection::getParent() const {
return cast_or_null<SyntheticSection>(Parent);

12
lld/ELF/MarkLive.cpp
View File

@ -241,11 +241,15 @@ template <class ELFT> static void doGcSections() {
// Preserve special sections and those which are specified in linker
// script KEEP command.
for (InputSectionBase *Sec : InputSections) {
// .eh_frame is always marked as live now, but also it can reference to
// sections that contain personality. We preserve all non-text sections
// referred by .eh_frame here.
if (auto *EH = dyn_cast_or_null<EhInputSection>(Sec))
// Mark .eh_frame sections as live because there are usually no relocations
// that point to .eh_frames. Otherwise, the garbage collector would drop
// all of them. We also want to preserve personality routines and LSDA
// referenced by .eh_frame sections, so we scan them for that here.
if (auto *EH = dyn_cast_or_null<EhInputSection>(Sec)) {
EH->Live = true;
scanEhFrameSection<ELFT>(*EH, Enqueue);
}
if (Sec->Flags & SHF_LINK_ORDER)
continue;
if (isReserved<ELFT>(Sec) || Script->shouldKeep(Sec))