Mips direct object xgot support

This patch provides support for the MIPS relocations:

    *)  R_MIPS_GOT_HI16
    *)  R_MIPS_GOT_LO16
    *)  R_MIPS_CALL_HI16
    *)  R_MIPS_CALL_LO16

These are used for large GOT instruction sequences.

Contributer: Jack Carter
llvm-svn: 168471
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
index 9a35bb6..c078794 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
@@ -42,6 +42,8 @@
   case Mips::fixup_Mips_GOT_PAGE:
   case Mips::fixup_Mips_GOT_OFST:
   case Mips::fixup_Mips_GOT_DISP:
+  case Mips::fixup_Mips_GOT_LO16:
+  case Mips::fixup_Mips_CALL_LO16:
     break;
   case Mips::fixup_Mips_PC16:
     // So far we are only using this type for branches.
@@ -60,6 +62,8 @@
     break;
   case Mips::fixup_Mips_HI16:
   case Mips::fixup_Mips_GOT_Local:
+  case Mips::fixup_Mips_GOT_HI16:
+  case Mips::fixup_Mips_CALL_HI16:
     // Get the 2nd 16-bits. Also add 1 if bit 15 is 1.
     Value = ((Value + 0x8000) >> 16) & 0xffff;
     break;
@@ -179,7 +183,11 @@
       { "fixup_Mips_GOT_OFST",     0,     16,   0 },
       { "fixup_Mips_GOT_DISP",     0,     16,   0 },
       { "fixup_Mips_HIGHER",       0,     16,   0 },
-      { "fixup_Mips_HIGHEST",      0,     16,   0 }
+      { "fixup_Mips_HIGHEST",      0,     16,   0 },
+      { "fixup_Mips_GOT_HI16",     0,     16,   0 },
+      { "fixup_Mips_GOT_LO16",     0,     16,   0 },
+      { "fixup_Mips_CALL_HI16",    0,     16,   0 },
+      { "fixup_Mips_CALL_LO16",    0,     16,   0 }
     };
 
     if (Kind < FirstTargetFixupKind)
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
index 5d240fe..f82e203 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
@@ -179,6 +179,18 @@
   case Mips::fixup_Mips_HIGHEST:
     Type = ELF::R_MIPS_HIGHEST;
     break;
+  case Mips::fixup_Mips_GOT_HI16:
+    Type = ELF::R_MIPS_GOT_HI16;
+    break;
+  case Mips::fixup_Mips_GOT_LO16:
+    Type = ELF::R_MIPS_GOT_LO16;
+    break;
+  case Mips::fixup_Mips_CALL_HI16:
+    Type = ELF::R_MIPS_CALL_HI16;
+    break;
+  case Mips::fixup_Mips_CALL_LO16:
+    Type = ELF::R_MIPS_CALL_LO16;
+    break;
   }
   return Type;
 }
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h b/llvm/lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h
index 77faec5..f963900 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h
@@ -116,6 +116,18 @@
     // resulting in - R_MIPS_HIGHEST
     fixup_Mips_HIGHEST,
 
+    // resulting in - R_MIPS_GOT_HI16
+    fixup_Mips_GOT_HI16,
+
+    // resulting in - R_MIPS_GOT_LO16
+    fixup_Mips_GOT_LO16,
+
+    // resulting in - R_MIPS_CALL_HI16
+    fixup_Mips_CALL_HI16,
+
+    // resulting in - R_MIPS_CALL_LO16
+    fixup_Mips_CALL_LO16,
+
     // Marker
     LastTargetFixupKind,
     NumTargetFixupKinds = LastTargetFixupKind - FirstTargetFixupKind
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp
index 7fbdae0..da1e4552 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp
@@ -287,6 +287,18 @@
   case MCSymbolRefExpr::VK_Mips_HIGHEST:
     FixupKind = Mips::fixup_Mips_HIGHEST;
     break;
+  case MCSymbolRefExpr::VK_Mips_GOT_HI16:
+    FixupKind = Mips::fixup_Mips_GOT_HI16;
+    break;
+  case MCSymbolRefExpr::VK_Mips_GOT_LO16:
+    FixupKind = Mips::fixup_Mips_GOT_LO16;
+    break;
+  case MCSymbolRefExpr::VK_Mips_CALL_HI16:
+    FixupKind = Mips::fixup_Mips_CALL_HI16;
+    break;
+  case MCSymbolRefExpr::VK_Mips_CALL_LO16:
+    FixupKind = Mips::fixup_Mips_CALL_LO16;
+    break;
   } // switch
 
   Fixups.push_back(MCFixup::Create(0, MO.getExpr(), MCFixupKind(FixupKind)));