[mips][ias] Work around incorrect another microMIPS relocation evaluation exposed by r268900

As explained in r269196, microMIPS has a special case that is not correctly
implemented in LLVM. If we have a symbol 'foo' which is equivalent to
'.text+0x10'. The value of an R_MICROMIPS_LO16 relocation using 'foo' is
'foo+0x11' and not 'foo+0x10'. The in-place addend should therefore be 0x11.

This commit reverts a little more of the effect of r268900 by keeping the
symbol when the STO_MIPS_MICROMIPS flag is set for R_MIPS_GPREL32 relocations.
This fixes SingleSource/UnitTests/2003-08-11-VaListArg, and
SingleSource/UnitTests/2003-05-07-VarArgs for microMIPS.

I believe there are additional relocations that have the same issue (e.g.
R_MIPS_64, and R_MIPS_GPREL16) but for now I'm focusing on restoring our
internal buildbots back to the green state we had in r268899.

llvm-svn: 269294

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
index e47868db1a4..a5e63856401 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
@@ -518,13 +518,13 @@ bool MipsELFObjectWriter::needsRelocateWithSymbol(const MCSymbol &Sym,
 
   case ELF::R_MIPS_16:
   case ELF::R_MIPS_32:
+  case ELF::R_MIPS_GPREL32:
     if (cast<MCSymbolELF>(Sym).getOther() & ELF::STO_MIPS_MICROMIPS)
       return true;
     // fallthrough
   case ELF::R_MIPS_26:
   case ELF::R_MIPS_64:
   case ELF::R_MIPS_GPREL16:
-  case ELF::R_MIPS_GPREL32:
   case ELF::R_MIPS_PC16:
   case ELF::R_MIPS_SUB:
     return false;