Revert "[ELF] Only mark as DT_NEEDED libs that are strictly necessary"

This reverts commit r219353 because that seems to break buildbots.

llvm-svn: 219369

lld/include/lld/ReaderWriter/ELFLinkingContext.h

@@ -90,15 +90,6 @@ public:
                                    const Reference &) const {
     return false;
   }
-
-  /// \brief Is this a copy relocation?
-  ///
-  /// If this is a copy relocation, its target must be an ObjectAtom. We must
-  /// include in DT_NEEDED the name of the library where this object came from.
-  virtual bool isCopyRelocation(const Reference &) const {
-    return false;
-  }
-
   bool validateImpl(raw_ostream &diagnostics) override;
 
   /// \brief Does the linker allow dynamic libraries to be linked with?

lld/lib/ReaderWriter/ELF/AArch64/AArch64LinkingContext.h

@@ -59,15 +59,6 @@ public:
     }
   }
 
-  bool isCopyRelocation(const Reference &r) const override {
-    if (r.kindNamespace() != Reference::KindNamespace::ELF)
-      return false;
-    assert(r.kindArch() == Reference::KindArch::AArch64);
-    if (r.kindValue() == llvm::ELF::R_AARCH64_COPY)
-      return true;
-    return false;
-  }
-
   bool isPLTRelocation(const DefinedAtom &,
                                const Reference &r) const override {
     if (r.kindNamespace() != Reference::KindNamespace::ELF)

lld/lib/ReaderWriter/ELF/AArch64/AArch64RelocationPass.cpp

@@ -452,7 +452,7 @@ public:
     if (obj != _objectMap.end())
       return obj->second;
 
-    auto oa = new (_file._alloc) ObjectAtom(_file, a);
+    auto oa = new (_file._alloc) ObjectAtom(_file);
     // This needs to point to the atom that we just created.
     oa->addReferenceELF_AArch64(R_AARCH64_COPY, 0, oa, 0);
 

lld/lib/ReaderWriter/ELF/Atoms.h

@@ -689,11 +689,8 @@ public:
 /// \brief Atom which represents an object for which a COPY relocation will be
 ///   generated.
 class ObjectAtom : public SimpleELFDefinedAtom {
-  const SharedLibraryAtom *_sla;
-
 public:
-  ObjectAtom(const File &f, const SharedLibraryAtom *sla)
-      : SimpleELFDefinedAtom(f), _sla(sla) {}
+  ObjectAtom(const File &f) : SimpleELFDefinedAtom(f) {}
 
   Scope scope() const override { return scopeGlobal; }
 
@@ -716,8 +713,6 @@ public:
 
   StringRef name() const override { return _name; }
 
-  const SharedLibraryAtom *getOriginalOwner() const { return _sla; }
-
   std::string _name;
   uint64_t _size;
 };

lld/lib/ReaderWriter/ELF/DefaultLayout.h

@@ -10,7 +10,6 @@
 #ifndef LLD_READER_WRITER_ELF_DEFAULT_LAYOUT_H
 #define LLD_READER_WRITER_ELF_DEFAULT_LAYOUT_H
 
-#include "Atoms.h"
 #include "Chunk.h"
 #include "HeaderChunks.h"
 #include "Layout.h"
@@ -172,7 +171,6 @@ public:
   typedef typename std::vector<lld::AtomLayout *>::iterator AbsoluteAtomIterT;
 
   typedef llvm::DenseSet<const Atom *> AtomSetT;
-  typedef llvm::DenseSet<const SharedLibraryAtom *> SharedLibraryAtomSetT;
 
   DefaultLayout(const ELFLinkingContext &context) : _context(context) {}
 
@@ -305,10 +303,6 @@ public:
     return _referencedDynAtoms.count(a);
   }
 
-  const SharedLibraryAtomSetT &getCopiedDynAtoms() const {
-    return _copiedDynAtoms;
-  }
-
 protected:
   /// \brief Allocate a new section.
   virtual AtomSection<ELFT> *createSection(
@@ -331,7 +325,6 @@ protected:
   LLD_UNIQUE_BUMP_PTR(RelocationTable<ELFT>) _pltRelocationTable;
   std::vector<lld::AtomLayout *> _absoluteAtoms;
   AtomSetT _referencedDynAtoms;
-  SharedLibraryAtomSetT _copiedDynAtoms;
   const ELFLinkingContext &_context;
 };
 
@@ -589,14 +582,7 @@ ErrorOr<const lld::AtomLayout &> DefaultLayout<ELFT>::addAtom(const Atom *atom)
       if (isa<UndefinedAtom>(reloc->target()) && isLocalReloc)
         continue;
 
-      if (!_context.isCopyRelocation(*reloc)) {
-        _referencedDynAtoms.insert(reloc->target());
-        continue;
-      }
-
-      const ObjectAtom *oa = dyn_cast<ObjectAtom>(reloc->target());
-      assert (oa != nullptr && "Targets of copy relocs must be ObjectAtoms");
-      _copiedDynAtoms.insert(oa->getOriginalOwner());
+      _referencedDynAtoms.insert(reloc->target());
     }
 
     return section->appendAtom(atom);

lld/lib/ReaderWriter/ELF/Mips/MipsDynamicLibraryWriter.h

@@ -37,6 +37,10 @@ protected:
     return std::error_code();
   }
 
+  bool isNeededTagRequired(const SharedLibraryAtom *sla) const override {
+    return _writeHelper.isNeededTagRequired(sla);
+  }
+
   LLD_UNIQUE_BUMP_PTR(DynamicTable<ELFT>) createDynamicTable();
 
   LLD_UNIQUE_BUMP_PTR(DynamicSymbolTable<ELFT>) createDynamicSymbolTable();

lld/lib/ReaderWriter/ELF/Mips/MipsELFWriters.h

@@ -69,6 +69,11 @@ public:
     return file;
   }
 
+  bool isNeededTagRequired(const SharedLibraryAtom *sla) const {
+    return _targetLayout.isReferencedByDefinedAtom(sla) ||
+           _targetLayout.isCopied(sla);
+  }
+
 private:
   MipsLinkingContext &_ctx;
   MipsTargetLayout<ELFT> &_targetLayout;

lld/lib/ReaderWriter/ELF/Mips/MipsExecutableWriter.h

@@ -38,6 +38,10 @@ protected:
     return std::error_code();
   }
 
+  bool isNeededTagRequired(const SharedLibraryAtom *sla) const override {
+    return _writeHelper.isNeededTagRequired(sla);
+  }
+
   LLD_UNIQUE_BUMP_PTR(DynamicTable<ELFT>) createDynamicTable();
 
   LLD_UNIQUE_BUMP_PTR(DynamicSymbolTable<ELFT>) createDynamicSymbolTable();

lld/lib/ReaderWriter/ELF/Mips/MipsLinkingContext.cpp

@@ -65,15 +65,6 @@ bool MipsLinkingContext::isDynamicRelocation(const DefinedAtom &,
   }
 }
 
-bool MipsLinkingContext::isCopyRelocation(const Reference &r) const {
-  if (r.kindNamespace() != Reference::KindNamespace::ELF)
-    return false;
-  assert(r.kindArch() == Reference::KindArch::Mips);
-  if (r.kindValue() == llvm::ELF::R_MIPS_COPY)
-    return true;
-  return false;
-}
-
 bool MipsLinkingContext::isPLTRelocation(const DefinedAtom &,
                                          const Reference &r) const {
   if (r.kindNamespace() != Reference::KindNamespace::ELF)

lld/lib/ReaderWriter/ELF/Mips/MipsLinkingContext.h

@@ -47,7 +47,6 @@ public:
   bool isRelaOutputFormat() const override { return false; }
   bool isDynamicRelocation(const DefinedAtom &,
                            const Reference &r) const override;
-  bool isCopyRelocation(const Reference &r) const override;
   bool isPLTRelocation(const DefinedAtom &, const Reference &r) const override;
 };
 

lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp

@@ -781,7 +781,7 @@ RelocationPass<ELFT>::getObjectEntry(const SharedLibraryAtom *a) {
   if (obj != _objectMap.end())
     return obj->second;
 
-  auto oa = new (_file._alloc) ObjectAtom(_file, a);
+  auto oa = new (_file._alloc) ObjectAtom(_file);
   oa->addReferenceELF_Mips(R_MIPS_COPY, 0, oa, 0);
   oa->_name = a->name();
   oa->_size = a->size();

lld/lib/ReaderWriter/ELF/Mips/MipsTargetHandler.h

@@ -62,6 +62,26 @@ public:
     }
   }
 
+  ErrorOr<const lld::AtomLayout &> addAtom(const Atom *atom) override {
+    // Maintain:
+    // 1. Set of shared library atoms referenced by regular defined atoms.
+    // 2. Set of shared library atoms have corresponding R_MIPS_COPY copies.
+    if (const auto *da = dyn_cast<DefinedAtom>(atom))
+      for (const Reference *ref : *da) {
+        if (ref->kindNamespace() == lld::Reference::KindNamespace::ELF) {
+          assert(ref->kindArch() == Reference::KindArch::Mips);
+          if (ref->kindValue() == llvm::ELF::R_MIPS_COPY)
+            _copiedDynSymNames.insert(atom->name());
+        }
+      }
+
+    return TargetLayout<ELFType>::addAtom(atom);
+  }
+
+  bool isCopied(const SharedLibraryAtom *sla) const {
+    return _copiedDynSymNames.count(sla->name());
+  }
+
   /// \brief GP offset relative to .got section.
   uint64_t getGPOffset() const { return 0x7FF0; }
 
@@ -89,6 +109,7 @@ private:
   MipsPLTSection<ELFType> *_pltSection;
   llvm::Optional<AtomLayout *> _gpAtom;
   llvm::Optional<AtomLayout *> _gpDispAtom;
+  llvm::StringSet<> _copiedDynSymNames;
 };
 
 /// \brief Mips Runtime file.

lld/lib/ReaderWriter/ELF/OutputELFWriter.h

@@ -180,14 +180,11 @@ template <class ELFT>
 void OutputELFWriter<ELFT>::buildDynamicSymbolTable(const File &file) {
   ScopedTask task(getDefaultDomain(), "buildDynamicSymbolTable");
   for (const auto &sla : file.sharedLibrary()) {
-    if (!isDynSymEntryRequired(sla))
-      continue;
-    _dynamicSymbolTable->addSymbol(sla, ELF::SHN_UNDEF);
+    if (isDynSymEntryRequired(sla))
+      _dynamicSymbolTable->addSymbol(sla, ELF::SHN_UNDEF);
     if (isNeededTagRequired(sla))
       _soNeeded.insert(sla->loadName());
   }
-  for (const auto &sla : _layout.getCopiedDynAtoms())
-    _soNeeded.insert(sla->loadName());
   // Never mark the dynamic linker as DT_NEEDED
   _soNeeded.erase(sys::path::filename(_context.getInterpreter()));
   for (const auto &loadName : _soNeeded) {

lld/lib/ReaderWriter/ELF/X86_64/X86_64LinkingContext.h

@@ -58,15 +58,6 @@ public:
     }
   }
 
-  bool isCopyRelocation(const Reference &r) const override {
-    if (r.kindNamespace() != Reference::KindNamespace::ELF)
-      return false;
-    assert(r.kindArch() == Reference::KindArch::x86_64);
-    if (r.kindValue() == llvm::ELF::R_X86_64_COPY)
-      return true;
-    return false;
-  }
-
   virtual bool isPLTRelocation(const DefinedAtom &,
                                const Reference &r) const override {
     if (r.kindNamespace() != Reference::KindNamespace::ELF)

lld/lib/ReaderWriter/ELF/X86_64/X86_64RelocationPass.cpp

@@ -430,7 +430,7 @@ public:
     if (obj != _objectMap.end())
       return obj->second;
 
-    auto oa = new (_file._alloc) ObjectAtom(_file, a);
+    auto oa = new (_file._alloc) ObjectAtom(_file);
     // This needs to point to the atom that we just created.
     oa->addReferenceELF_x86_64(R_X86_64_COPY, 0, oa, 0);