[X86] Replace reloc_global_offset_table8 with R_X86_64_GOTPC64

Author: MaskRay

llvm/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp

@@ -638,7 +638,6 @@ const MCFixupKindInfo &X86AsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
       {"reloc_signed_4byte", 0, 32, 0},
       {"reloc_signed_4byte_relax", 0, 32, 0},
       {"reloc_global_offset_table", 0, 32, 0},
-      {"reloc_global_offset_table8", 0, 64, 0},
       {"reloc_branch_4byte_pcrel", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
       // clang-format on
   };
@@ -696,7 +695,6 @@ static unsigned getFixupKindSize(unsigned Kind) {
   case FK_PCRel_8:
   case FK_SecRel_8:
   case FK_Data_8:
-  case X86::reloc_global_offset_table8:
     return 8;
   }
 }

llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp

@@ -54,10 +54,6 @@ static X86_64RelType getType64(MCFixupKind Kind,
     llvm_unreachable("Unimplemented");
   case FK_NONE:
     return RT64_NONE;
-  case X86::reloc_global_offset_table8:
-    Modifier = MCSymbolRefExpr::VK_GOT;
-    IsPCRel = true;
-    return RT64_64;
   case FK_Data_8:
     return RT64_64;
   case X86::reloc_signed_4byte:

llvm/lib/Target/X86/MCTargetDesc/X86FixupKinds.h

@@ -35,7 +35,6 @@ enum Fixups {
   reloc_global_offset_table,                 // 32-bit, relative to the start
                                              // of the instruction. Used only
                                              // for _GLOBAL_OFFSET_TABLE_.
-  reloc_global_offset_table8,                // 64-bit variant.
   reloc_branch_4byte_pcrel,                  // 32-bit PC relative branch.
   // Marker
   LastTargetFixupKind,

llvm/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp

@@ -14,6 +14,7 @@
 #include "MCTargetDesc/X86FixupKinds.h"
 #include "MCTargetDesc/X86MCTargetDesc.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/BinaryFormat/ELF.h"
 #include "llvm/MC/MCCodeEmitter.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCExpr.h"
@@ -542,7 +543,8 @@ void X86MCCodeEmitter::emitImmediate(const MCOperand &DispOp, SMLoc Loc,
       assert(ImmOffset == 0);
 
       if (Size == 8) {
-        FixupKind = MCFixupKind(X86::reloc_global_offset_table8);
+        FixupKind =
+            MCFixupKind(FirstLiteralRelocationKind + ELF::R_X86_64_GOTPC64);
       } else {
         assert(Size == 4);
         FixupKind = MCFixupKind(X86::reloc_global_offset_table);