Move the support for using .init_array from ARM to the generic

TargetLoweringObjectFileELF. Use this to support it on X86. Unlike ARM,
on X86 it is not easy to find out if .init_array should be used or not, so
the decision is made via TargetOptions and defaults to off.

Add a command line option to llc that enables it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158692 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/X86/X86TargetObjectFile.cpp

@@ -9,12 +9,15 @@
 
 #include "X86TargetObjectFile.h"
 #include "X86TargetMachine.h"
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCSectionELF.h"
 #include "llvm/MC/MCSectionMachO.h"
 #include "llvm/Target/Mangler.h"
 #include "llvm/Support/Dwarf.h"
+#include "llvm/Support/ELF.h"
 using namespace llvm;
 using namespace dwarf;
 
@@ -42,3 +45,9 @@ getCFIPersonalitySymbol(const GlobalValue *GV, Mangler *Mang,
                         MachineModuleInfo *MMI) const {
   return Mang->getSymbol(GV);
 }
+
+void
+X86LinuxTargetObjectFile::Initialize(MCContext &Ctx, const TargetMachine &TM) {
+  TargetLoweringObjectFileELF::Initialize(Ctx, TM);
+  InitializeELF(TM.Options.UseInitArray);
+}