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Move clearOutputSections earlier. 

Now removeUnusedSyntheticSections operates entirely on the linker
script.

llvm-svn: 307043
This commit is contained in:
Rafael Espindola 2017-07-03 16:54:39 +00:00
parent bdfb3b1d5f
commit c080ff64dc
1 changed files with 19 additions and 7 deletions
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26
lld/ELF/Writer.cpp
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@ -1132,7 +1132,7 @@ static void applySynthetic(const std::vector<SyntheticSection *> &Sections,
// to make them visible from linkescript side. But not all sections are always
// required to be in output. For example we don't need dynamic section content
// sometimes. This function filters out such unused sections from the output.
static void removeUnusedSyntheticSections(std::vector<OutputSection *> &V) {
static void removeUnusedSyntheticSections() {
// All input synthetic sections that can be empty are placed after
// all regular ones. We iterate over them all and exit at first
// non-synthetic.
@ -1145,12 +1145,24 @@ static void removeUnusedSyntheticSections(std::vector<OutputSection *> &V) {
continue;
if ((SS == InX::Got || SS == InX::MipsGot) && ElfSym::GlobalOffsetTable)
continue;
OS->Sections.erase(std::find(OS->Sections.begin(), OS->Sections.end(), SS));
SS->Live = false;
OutputSectionCommand *Cmd = Script->getCmd(OS);
BaseCommand **Empty = nullptr;
for (BaseCommand *&B : Cmd->Commands) {
if (auto *ISD = dyn_cast<InputSectionDescription>(B)) {
auto I = std::find(ISD->Sections.begin(), ISD->Sections.end(), SS);
if (I != ISD->Sections.end())
ISD->Sections.erase(I);
if (ISD->Sections.empty())
Empty = &B;
}
}
if (Empty)
Cmd->Commands.erase(std::vector<BaseCommand *>::iterator(Empty));
// If there are no other sections in the output section, remove it from the
// output.
if (OS->Sections.empty()) {
V.erase(std::find(V.begin(), V.end(), OS));
if (Cmd->Commands.empty()) {
// Also remove script commands matching the output section.
auto &Cmds = Script->Opt.Commands;
auto I = std::remove_if(Cmds.begin(), Cmds.end(), [&](BaseCommand *Cmd) {
@ -1227,9 +1239,9 @@ template <class ELFT> void Writer<ELFT>::finalizeSections() {
return;
addPredefinedSections();
removeUnusedSyntheticSections(OutputSections);
clearOutputSections();
removeUnusedSyntheticSections();
sortSections();
// Now that we have the final list, create a list of all the