[ELF] Move ppc64noTocRelax to Ctx. NFC

Ctx was introduced in March 2022 as a more suitable place for such
singletons.

Author: MaskRay

lld/ELF/Arch/PPC64.cpp

@@ -1593,7 +1593,7 @@ void PPC64::relocateAlloc(InputSectionBase &sec, uint8_t *buf) const {
       // entry, there may be R_PPC64_TOC16_HA not paired with
       // R_PPC64_TOC16_LO_DS. Don't relax. This loses some relaxation
       // opportunities but is safe.
-      if (ppc64noTocRelax.count({rel.sym, rel.addend}) ||
+      if (ctx.ppc64noTocRelax.count({rel.sym, rel.addend}) ||
           !tryRelaxPPC64TocIndirection(rel, loc))
         relocate(loc, rel, val);
       break;

lld/ELF/Config.h

@@ -582,6 +582,11 @@ struct Ctx {
   unsigned scriptSymOrderCounter = 1;
   llvm::DenseMap<const Symbol *, unsigned> scriptSymOrder;
 
+  // The set of TOC entries (.toc + addend) for which we should not apply
+  // toc-indirect to toc-relative relaxation. const Symbol * refers to the
+  // STT_SECTION symbol associated to the .toc input section.
+  llvm::DenseSet<std::pair<const Symbol *, uint64_t>> ppc64noTocRelax;
+
   void reset();
 
   llvm::raw_fd_ostream openAuxiliaryFile(llvm::StringRef, std::error_code &);

lld/ELF/Driver.cpp

@@ -123,6 +123,7 @@ void Ctx::reset() {
   needsTlsLd.store(false, std::memory_order_relaxed);
   scriptSymOrderCounter = 1;
   scriptSymOrder.clear();
+  ppc64noTocRelax.clear();
   ltoAllVtablesHaveTypeInfos = false;
 }
 

lld/ELF/InputSection.cpp

@@ -34,8 +34,6 @@ using namespace llvm::sys;
 using namespace lld;
 using namespace lld::elf;
 
-DenseSet<std::pair<const Symbol *, uint64_t>> elf::ppc64noTocRelax;
-
 // Returns a string to construct an error message.
 std::string lld::toString(const InputSectionBase *sec) {
   return (toString(sec->file) + ":(" + sec->name + ")").str();

lld/ELF/InputSection.h

@@ -498,12 +498,6 @@ inline bool isDebugSection(const InputSectionBase &sec) {
   return (sec.flags & llvm::ELF::SHF_ALLOC) == 0 &&
          sec.name.starts_with(".debug");
 }
-
-// The set of TOC entries (.toc + addend) for which we should not apply
-// toc-indirect to toc-relative relaxation. const Symbol * refers to the
-// STT_SECTION symbol associated to the .toc input section.
-extern llvm::DenseSet<std::pair<const Symbol *, uint64_t>> ppc64noTocRelax;
-
 } // namespace elf
 
 std::string toString(const elf::InputSectionBase *);

lld/ELF/Relocations.cpp

@@ -1495,7 +1495,7 @@ void RelocationScanner::scanOne(typename Relocs<RelTy>::const_iterator &i) {
     // InputSectionBase::relocateAlloc().
     if (type == R_PPC64_TOC16_LO && sym.isSection() && isa<Defined>(sym) &&
         cast<Defined>(sym).section->name == ".toc")
-      ppc64noTocRelax.insert({&sym, addend});
+      ctx.ppc64noTocRelax.insert({&sym, addend});
 
     if ((type == R_PPC64_TLSGD && expr == R_TLSDESC_CALL) ||
         (type == R_PPC64_TLSLD && expr == R_TLSLD_HINT)) {

lld/ELF/Writer.cpp

@@ -1800,7 +1800,6 @@ template <class ELFT> void Writer<ELFT>::finalizeSections() {
     // that we can correctly decide if a dynamic relocation is needed. This is
     // called after processSymbolAssignments() because it needs to know whether
     // a linker-script-defined symbol is absolute.
-    ppc64noTocRelax.clear();
     scanRelocations<ELFT>();
     reportUndefinedSymbols();
     postScanRelocations();