[mips] Use MipsMCExpr instead of MCSymbolRefExpr for all relocations.

Summary:
This is much closer to the way MIPS relocation expressions work
(%hi(foo + 2) rather than %hi(foo) + 2) and removes the need for the
various bodges in MipsAsmParser::evaluateRelocExpr().

Removing those bodges ensures that the constant stored in MCValue is the
full 32 or 64-bit (depending on ABI) offset from the symbol. This will be used
to correct the %hi/%lo matching needed to sort the relocation table correctly.

As part of this:
* Gave MCExpr::print() the ability to omit parenthesis when emitting a
  symbol reference inside a MipsMCExpr operator like %hi(X). Without this
  we print things like %lo(($L1)).
* %hi(%neg(%gprel(X))) is now three MipsMCExpr's instead of one. Most of
  the related special cases have been removed or moved to MipsMCExpr. We
  can remove the rest as we gain support for the less common relocations
  when they are not part of this specific combination.
* Renamed MipsMCExpr::VariantKind and the enum prefix ('VK_') to avoid confusion
  with MCSymbolRefExpr::VariantKind and its prefix (also 'VK_').
* fixup_Mips_GOT_Local and fixup_Mips_GOT_Global were found to be identical
  and merged into fixup_Mips_GOT.
* MO_GOT16 and MO_GOT turned out to be identical and have been merged into
  MO_GOT.
* VK_Mips_GOT and VK_Mips_GOT16 turned out to be the same thing so they
  have been merged into MEK_GOT

Reviewers: sdardis

Subscribers: dsanders, sdardis, llvm-commits

Differential Revision: http://reviews.llvm.org/D19716

llvm-svn: 268379

3 files changed, 3 insertions, 33 deletions

diff --git a/llvm/lib/MC/ELFObjectWriter.cpp b/llvm/lib/MC/ELFObjectWriter.cpp
index 54bdaff7f0b..4fb583d4ff1 100644
--- a/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/llvm/lib/MC/ELFObjectWriter.cpp
@@ -536,7 +536,6 @@ bool ELFObjectWriter::shouldRelocateWithSymbol(const MCAssembler &Asm,
   case MCSymbolRefExpr::VK_GOT:
   case MCSymbolRefExpr::VK_PLT:
   case MCSymbolRefExpr::VK_GOTPCREL:
-  case MCSymbolRefExpr::VK_Mips_GOT:
   case MCSymbolRefExpr::VK_PPC_GOT_LO:
   case MCSymbolRefExpr::VK_PPC_GOT_HI:
   case MCSymbolRefExpr::VK_PPC_GOT_HA:
diff --git a/llvm/lib/MC/MCELFStreamer.cpp b/llvm/lib/MC/MCELFStreamer.cpp
index 1000da9e766..6c8ce7c46eb 100644
--- a/llvm/lib/MC/MCELFStreamer.cpp
+++ b/llvm/lib/MC/MCELFStreamer.cpp
@@ -412,10 +412,6 @@ void MCELFStreamer::fixSymbolsInTLSFixups(const MCExpr *expr) {
     case MCSymbolRefExpr::VK_TPREL:
     case MCSymbolRefExpr::VK_DTPOFF:
     case MCSymbolRefExpr::VK_DTPREL:
-    case MCSymbolRefExpr::VK_Mips_TLSGD:
-    case MCSymbolRefExpr::VK_Mips_GOTTPREL:
-    case MCSymbolRefExpr::VK_Mips_TPREL_HI:
-    case MCSymbolRefExpr::VK_Mips_TPREL_LO:
     case MCSymbolRefExpr::VK_PPC_DTPMOD:
     case MCSymbolRefExpr::VK_PPC_TPREL_LO:
     case MCSymbolRefExpr::VK_PPC_TPREL_HI:
diff --git a/llvm/lib/MC/MCExpr.cpp b/llvm/lib/MC/MCExpr.cpp
index c74db853ebf..4dfb9719fa7 100644
--- a/llvm/lib/MC/MCExpr.cpp
+++ b/llvm/lib/MC/MCExpr.cpp
@@ -30,7 +30,7 @@ STATISTIC(MCExprEvaluate, "Number of MCExpr evaluations");
 }
 }
 
-void MCExpr::print(raw_ostream &OS, const MCAsmInfo *MAI) const {
+void MCExpr::print(raw_ostream &OS, const MCAsmInfo *MAI, bool InParens) const {
   switch (getKind()) {
   case MCExpr::Target:
     return cast<MCTargetExpr>(this)->printImpl(OS, MAI);
@@ -43,7 +43,8 @@ void MCExpr::print(raw_ostream &OS, const MCAsmInfo *MAI) const {
     const MCSymbol &Sym = SRE.getSymbol();
     // Parenthesize names that start with $ so that they don't look like
     // absolute names.
-    bool UseParens = Sym.getName().size() && Sym.getName()[0] == '$';
+    bool UseParens =
+        !InParens && Sym.getName().size() && Sym.getName()[0] == '$';
     if (UseParens) {
       OS << '(';
       Sym.print(OS, MAI);
@@ -264,32 +265,6 @@ StringRef MCSymbolRefExpr::getVariantKindName(VariantKind Kind) {
   case VK_PPC_GOT_TLSLD_HA: return "got@tlsld@ha";
   case VK_PPC_TLSLD: return "tlsld";
   case VK_PPC_LOCAL: return "local";
-  case VK_Mips_GPREL: return "GPREL";
-  case VK_Mips_GOT_CALL: return "GOT_CALL";
-  case VK_Mips_GOT16: return "GOT16";
-  case VK_Mips_GOT: return "GOT";
-  case VK_Mips_ABS_HI: return "ABS_HI";
-  case VK_Mips_ABS_LO: return "ABS_LO";
-  case VK_Mips_TLSGD: return "TLSGD";
-  case VK_Mips_TLSLDM: return "TLSLDM";
-  case VK_Mips_DTPREL_HI: return "DTPREL_HI";
-  case VK_Mips_DTPREL_LO: return "DTPREL_LO";
-  case VK_Mips_GOTTPREL: return "GOTTPREL";
-  case VK_Mips_TPREL_HI: return "TPREL_HI";
-  case VK_Mips_TPREL_LO: return "TPREL_LO";
-  case VK_Mips_GPOFF_HI: return "GPOFF_HI";
-  case VK_Mips_GPOFF_LO: return "GPOFF_LO";
-  case VK_Mips_GOT_DISP: return "GOT_DISP";
-  case VK_Mips_GOT_PAGE: return "GOT_PAGE";
-  case VK_Mips_GOT_OFST: return "GOT_OFST";
-  case VK_Mips_HIGHER:   return "HIGHER";
-  case VK_Mips_HIGHEST:  return "HIGHEST";
-  case VK_Mips_GOT_HI16: return "GOT_HI16";
-  case VK_Mips_GOT_LO16: return "GOT_LO16";
-  case VK_Mips_CALL_HI16: return "CALL_HI16";
-  case VK_Mips_CALL_LO16: return "CALL_LO16";
-  case VK_Mips_PCREL_HI16: return "PCREL_HI16";
-  case VK_Mips_PCREL_LO16: return "PCREL_LO16";
   case VK_COFF_IMGREL32: return "IMGREL";
   case VK_Hexagon_PCREL: return "PCREL";
   case VK_Hexagon_LO16: return "LO16";