[ELF][x86-64] Add the _GLOBAL_OFFSET_TABLE_ Atom in the correct location.

Now we link against glibc without --noinhibit-exec.

llvm-svn: 174150

2 files changed, 42 insertions, 3 deletions

diff --git a/lld/lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.cpp b/lld/lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.cpp
index 3369f8dce57..398ff5fa281 100644
--- a/lld/lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.cpp
+++ b/lld/lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.cpp
@@ -16,6 +16,10 @@ using namespace elf;
 
 using namespace llvm::ELF;
 
+X86_64TargetHandler::X86_64TargetHandler(X86_64TargetInfo &targetInfo)
+    : DefaultTargetHandler(targetInfo), _gotFile(targetInfo),
+      _relocationHandler(targetInfo), _targetLayout(targetInfo) {}
+
 namespace {
 /// \brief R_X86_64_64 - word64: S + A
 void reloc64(uint8_t *location, uint64_t P, uint64_t S, int64_t A) {
@@ -87,7 +91,32 @@ ErrorOr<void> X86_64TargetRelocationHandler::applyRelocation(
   return error_code::success();
 }
 
-X86_64TargetHandler::X86_64TargetHandler(X86_64TargetInfo &targetInfo)
-    : DefaultTargetHandler(targetInfo), _relocationHandler(targetInfo),
-      _targetLayout(targetInfo) {
+namespace {
+class GLOBAL_OFFSET_TABLEAtom : public SimpleDefinedAtom {
+public:
+  GLOBAL_OFFSET_TABLEAtom(const File &f) : SimpleDefinedAtom(f) {}
+
+  virtual StringRef name() const { return "_GLOBAL_OFFSET_TABLE_"; }
+
+  virtual Scope scope() const { return scopeGlobal; }
+
+  virtual SectionChoice sectionChoice() const { return sectionCustomRequired; }
+
+  virtual StringRef customSectionName() const { return ".got"; }
+
+  virtual ContentType contentType() const { return typeGOT; }
+
+  virtual uint64_t size() const { return 0; }
+
+  virtual ContentPermissions permissions() const { return permRW_; }
+
+  virtual ArrayRef<uint8_t> rawContent() const {
+    return ArrayRef<uint8_t>();
+  }
+};
+} // end anon namespace
+
+void X86_64TargetHandler::addFiles(InputFiles &f) {
+  _gotFile.addAtom(*new (_gotFile._alloc) GLOBAL_OFFSET_TABLEAtom(_gotFile));
+  f.appendFile(_gotFile);
 }
diff --git a/lld/lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.h b/lld/lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.h
index 179a8426d0b..9428478a152 100644
--- a/lld/lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.h
+++ b/lld/lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.h
@@ -13,6 +13,8 @@
 #include "DefaultTargetHandler.h"
 #include "TargetLayout.h"
 
+#include "lld/ReaderWriter/Simple.h"
+
 namespace lld {
 namespace elf {
 typedef llvm::object::ELFType<llvm::support::little, 8, true> X86_64ELFType;
@@ -44,7 +46,15 @@ public:
     return _relocationHandler;
   }
 
+  virtual void addFiles(InputFiles &f);
+
 private:
+  class GOTFile : public SimpleFile {
+  public:
+    GOTFile(const ELFTargetInfo &eti) : SimpleFile(eti, "GOTFile") {}
+    llvm::BumpPtrAllocator _alloc;
+  } _gotFile;
+
   X86_64TargetRelocationHandler _relocationHandler;
   TargetLayout<X86_64ELFType> _targetLayout;
 };