Cherry pick -r124899 from llvm root

llvm-trunk/lib/MC/ELFObjectWriter.cpp

Index: llvm-trunk/lib/MC/ELFObjectWriter.cpp
===================================================================
--- a/llvm-trunk/lib/MC/ELFObjectWriter.cpp
+++ b/llvm-trunk/lib/MC/ELFObjectWriter.cpp
@@ -276,6 +276,20 @@
 
     virtual void WriteHeader(uint64_t SectionDataSize, unsigned NumberOfSections);
 
+    /// Default e_flags = 0
+    virtual void WriteEFlags() { 
+      // @LOCALMOD-BEGIN

[robertm, 2011/02/23 15:08:58]

I am confused which way are you cherry picking.
Why is there a LOCAMOD here?

[jasonwkim, 2011/02/23 15:28:17]

Because our code uses EF_NACL_ALIGN_32 which the upstream doesn't know about,
thus the @LOCALMOD

This code was lifted from line 477 of the PNACL ELFObjectWriter.cpp I am also
merely preserving the localmod that was there

+      switch (TargetObjectWriter->getOSType()) {
+      case Triple::NativeClient:
+        Write32(ELF::EF_NACL_ALIGN_32);
+        break;
+      default:
+        Write32(0);   // e_flags = whatever the target wants
+        break;
+      }
+      // @LOCALMOD-END
+    }
+
     virtual void WriteSymbolEntry(MCDataFragment *SymtabF, MCDataFragment *ShndxF,
                           uint64_t name, uint8_t info,
                           uint64_t value, uint64_t size,
@@ -387,11 +401,16 @@
 
   class ARMELFObjectWriter : public ELFObjectWriter {
   public:
+    // FIXME: MCAssembler can't yet return the Subtarget,
+    enum { DefaultEABIVersion = 0x05000000U };
+
     ARMELFObjectWriter(MCELFObjectTargetWriter *MOTW,
                        raw_ostream &_OS,
                        bool IsLittleEndian);
 
     virtual ~ARMELFObjectWriter();
+
+    virtual void WriteEFlags();
   protected:
     virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
                                   bool IsPCRel, bool IsRelocWithSymbol,
@@ -474,16 +493,8 @@
   WriteWord(SectionDataSize + (is64Bit() ? sizeof(ELF::Elf64_Ehdr) :
             sizeof(ELF::Elf32_Ehdr)));  // e_shoff = sec hdr table off in bytes
 
-  // @LOCALMOD-BEGIN
-  switch (TargetObjectWriter->getOSType()) {
-  case Triple::NativeClient:
-    Write32(ELF::EF_NACL_ALIGN_32);
-    break;
-  default:
-    Write32(0);   // e_flags = whatever the target wants
-    break;
-  }
-  // @LOCALMOD-END
+   // e_flags = whatever the target wants
+  WriteEFlags();
 
   // e_ehsize = ELF header size
   Write16(is64Bit() ? sizeof(ELF::Elf64_Ehdr) : sizeof(ELF::Elf32_Ehdr));
@@ -1495,7 +1506,6 @@
 
 /// START OF SUBCLASSES for ELFObjectWriter
 //===- ARMELFObjectWriter -------------------------------------------===//
-
 ARMELFObjectWriter::ARMELFObjectWriter(MCELFObjectTargetWriter *MOTW,
                                        raw_ostream &_OS,
                                        bool IsLittleEndian)
@@ -1505,6 +1515,20 @@
 ARMELFObjectWriter::~ARMELFObjectWriter()
 {}
 
+// FIXME: get the real EABI Version from the Triple.
+void ARMELFObjectWriter::WriteEFlags() {
+  // @LOCALMOD-BEGIN
+  unsigned e_flag = ELF::EF_ARM_EABIMASK & DefaultEABIVersion;
+  switch (TargetObjectWriter->getOSType()) {
+  case Triple::NativeClient:
+    e_flag |= ELF::EF_NACL_ALIGN_32;
+    break;
+  default: break;
+  }
+  Write32(e_flag);
+  // @LOCALMOD-END
+}
+
 unsigned ARMELFObjectWriter::GetRelocType(const MCValue &Target,
                                           const MCFixup &Fixup,
                                           bool IsPCRel,