[ELF] - Simplify removeUnusedSyntheticSections a bit.

Previously`InX::Got` and InX::MipsGot synthetic sections
were not removed if ElfSym::GlobalOffsetTable was defined.
ElfSym::GlobalOffsetTable is a symbol for _GLOBAL_OFFSET_TABLE_.

Patch moves ElfSym::GlobalOffsetTable check out from removeUnusedSyntheticSections.
Also note that there was no point to check ElfSym::GlobalOffsetTable for MIPS case
because InX::MipsGot::empty() always returns false for non-relocatable case, and in case
of relocatable output we do not create special symbols anyways.

Differential revision: https://reviews.llvm.org/D37623

llvm-svn: 314099

diff --git a/lld/ELF/SyntheticSections.cpp b/lld/ELF/SyntheticSections.cpp
index 1f8df13..66b5351 100644 (file)
--- a/lld/ELF/SyntheticSections.cpp
+++ b/lld/ELF/SyntheticSections.cpp
@@ -656,9 +656,10 @@ uint64_t GotSection::getGlobalDynOffset(const SymbolBody &B) const {
 void GotSection::finalizeContents() { Size = NumEntries * Config->Wordsize; }
 
 bool GotSection::empty() const {
-  // If we have a relocation that is relative to GOT (such as GOTOFFREL),
-  // we need to emit a GOT even if it's empty.
-  return NumEntries == 0 && !HasGotOffRel;
+  // We need to emit a GOT even if it's empty if there's a relocation that is
+  // relative to GOT(such as GOTOFFREL) or there's a symbol that points to a GOT
+  // (i.e. _GLOBAL_OFFSET_TABLE_).
+  return NumEntries == 0 && !HasGotOffRel && !ElfSym::GlobalOffsetTable;
 }
 
 void GotSection::writeTo(uint8_t *Buf) {

diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index b4342a9..0e27bc9 100644 (file)
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -1187,8 +1187,6 @@ static void removeUnusedSyntheticSections() {
     OutputSection *OS = SS->getParent();
     if (!SS->empty() || !OS)
       continue;
-    if ((SS == InX::Got || SS == InX::MipsGot) && ElfSym::GlobalOffsetTable)
-      continue;
 
     std::vector<BaseCommand *>::iterator Empty = OS->Commands.end();
     for (auto I = OS->Commands.begin(), E = OS->Commands.end(); I != E; ++I) {