[mips][ias] N32/N64 must not sort the relocation table.

Doing so changes the evaluation order for relocation composition.

Patch By: Daniel Sanders

Reviewers: vkalintiris, atanasyan

Differential Revision: https://reviews.llvm.org/D26401

llvm-svn: 288666

1 files changed, 7 insertions, 0 deletions

diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
index 0bfd4690f47..b2efd726da5 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
@@ -419,6 +419,13 @@ unsigned MipsELFObjectWriter::getRelocType(MCContext &Ctx,
 /// always match using the expressions from the source.
 void MipsELFObjectWriter::sortRelocs(const MCAssembler &Asm,
                                      std::vector<ELFRelocationEntry> &Relocs) {
+
+  // We do not need to sort the relocation table for RELA relocations which
+  // N32/N64 uses as the relocation addend contains the value we require,
+  // rather than it being split across a pair of relocations.
+  if (hasRelocationAddend())
+    return;
+
   if (Relocs.size() < 2)
     return;