Completely rewrite ELFObjectWriter::RecordRelocation.

I started trying to fix a small issue, but this code has seen a small fix too
many.

The old code was fairly convoluted. Some of the issues it had:

* It failed to check if a symbol difference was in the some section when
  converting a relocation to pcrel.
* It failed to check if the relocation was already pcrel.
* The pcrel value computation was wrong in some cases (relocation-pc.s)
* It was missing quiet a few cases where it should not convert symbol
  relocations to section relocations, leaving the backends to patch it up.
* It would not propagate the fact that it had changed a relocation to pcrel,
  requiring a quiet nasty work around in ARM.
* It was missing comments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205076 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 34 deletions

diff --git a/lib/MC/MCELFObjectTargetWriter.cpp b/lib/MC/MCELFObjectTargetWriter.cpp
index 0c39e4a17e..4012c442e4 100644
--- a/lib/MC/MCELFObjectTargetWriter.cpp
+++ b/lib/MC/MCELFObjectTargetWriter.cpp
@@ -24,38 +24,6 @@ MCELFObjectTargetWriter::MCELFObjectTargetWriter(bool Is64Bit_,
     IsN64(IsN64_){
 }
 
-const MCSymbol *MCELFObjectTargetWriter::ExplicitRelSym(const MCAssembler &Asm,
-                                                        const MCValue &Target,
-                                                        const MCFragment &F,
-                                                        const MCFixup &Fixup,
-                                                        bool IsPCRel) const {
-  return NULL;
-}
-
-const MCSymbol *MCELFObjectTargetWriter::undefinedExplicitRelSym(const MCValue &Target,
-                                                                 const MCFixup &Fixup,
-                                                                 bool IsPCRel) const {
-  const MCSymbol &Symbol = Target.getSymA()->getSymbol();
-  return &Symbol.AliasedSymbol();
-}
-
-// ELF doesn't require relocations to be in any order. We sort by the r_offset,
-// just to match gnu as for easier comparison. The use type and index is an
-// arbitrary way of making the sort deterministic.
-static int cmpRel(const ELFRelocationEntry *AP, const ELFRelocationEntry *BP) {
-  const ELFRelocationEntry &A = *AP;
-  const ELFRelocationEntry &B = *BP;
-  if (A.r_offset != B.r_offset)
-    return B.r_offset - A.r_offset;
-  if (B.Type != A.Type)
-    return A.Type - B.Type;
-  if (B.Index != A.Index)
-    return B.Index - A.Index;
-  llvm_unreachable("ELFRelocs might be unstable!");
-}
-
-void
-MCELFObjectTargetWriter::sortRelocs(const MCAssembler &Asm,
-                                    std::vector<ELFRelocationEntry> &Relocs) {
-  array_pod_sort(Relocs.begin(), Relocs.end(), cmpRel);
+bool MCELFObjectTargetWriter::needsRelocateWithSymbol(unsigned Type) const {
+  return false;
 }