[mips] Implement generation of relocations "chains" used by N32 ABI

In case of using a "nested" relocation expressions like this
`%hi(%neg(%gp_rel()))`, N32 ABI requires generation of three consecutive
relocations. That differs from the N64 ABI case where all relocations
are packed into the single relocation record.

llvm-svn: 313879

1 files changed, 17 insertions, 0 deletions

diff --git a/llvm/lib/MC/ELFObjectWriter.cpp b/llvm/lib/MC/ELFObjectWriter.cpp
index b37a950908e..eef2757b93b 100644
--- a/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/llvm/lib/MC/ELFObjectWriter.cpp
@@ -1131,6 +1131,23 @@ void ELFObjectWriter::writeRelocations(const MCAssembler &Asm,
 
       if (hasRelocationAddend())
         write(uint32_t(Entry.Addend));
+
+      if (TargetObjectWriter->getEMachine() == ELF::EM_MIPS) {
+        if (uint32_t RType = TargetObjectWriter->getRType2(Entry.Type)) {
+          write(uint32_t(Entry.Offset));
+
+          ERE32.setSymbolAndType(0, RType);
+          write(ERE32.r_info);
+          write(uint32_t(0));
+        }
+        if (uint32_t RType = TargetObjectWriter->getRType3(Entry.Type)) {
+          write(uint32_t(Entry.Offset));
+
+          ERE32.setSymbolAndType(0, RType);
+          write(ERE32.r_info);
+          write(uint32_t(0));
+        }
+      }
     }
   }
 }