cmd/6l, cmd/internal/ld, cmd/internal/obj: remove Xsym/Xadd from compiler's Reloc

They don't really make any sense on this side of the compiler/linker divide.

Some of the code touching these fields was the support for R_TLS when
thechar=='6' which turns out to be dead and so I just removed all of that.

Change-Id: I4e265613c4e7fcc30a965fffb7fd5f45017f06f3
Reviewed-on: https://go-review.googlesource.com/9107
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/cmd/6l/asm.go

@@ -392,17 +392,6 @@ func elfreloc1(r *ld.Reloc, sectoff int64) int {
 		} else {
 			return -1
 		}
-
-	case obj.R_TLS:
-		if r.Siz == 4 {
-			if ld.Buildmode == ld.BuildmodeCShared {
-				ld.Thearch.Vput(ld.R_X86_64_GOTTPOFF | uint64(elfsym)<<32)
-			} else {
-				ld.Thearch.Vput(ld.R_X86_64_TPOFF32 | uint64(elfsym)<<32)
-			}
-		} else {
-			return -1
-		}
 	}
 
 	ld.Thearch.Vput(uint64(r.Xadd))

src/cmd/internal/ld/objfile.go

@@ -143,9 +143,9 @@ overwrite:
 			r.Siz = uint8(rdint(f))
 			r.Type = int32(rdint(f))
 			r.Add = rdint(f)
-			r.Xadd = rdint(f)
+			rdint(f) // Xadd, ignored
 			r.Sym = rdsym(ctxt, f, pkg)
-			r.Xsym = rdsym(ctxt, f, pkg)
+			rdsym(ctxt, f, pkg) // Xsym, ignored
 		}
 	}
 

src/cmd/internal/obj/arm/asm5.go

@@ -1673,8 +1673,6 @@ func asmout(ctxt *obj.Link, p *obj.Prog, o *Optab, out []uint32) {
 				if ctxt.Flag_shared != 0 {
 					rel.Add += ctxt.Pc - p.Pcrel.Pc - 8 - int64(rel.Siz)
 				}
-				rel.Xadd = rel.Add
-				rel.Xsym = rel.Sym
 			} else if ctxt.Flag_shared != 0 {
 				rel.Type = obj.R_PCREL
 				rel.Add += ctxt.Pc - p.Pcrel.Pc - 8

src/cmd/internal/obj/link.go

@@ -356,9 +356,7 @@ type Reloc struct {
 	Siz  uint8
 	Type int32
 	Add  int64
-	Xadd int64
 	Sym  *LSym
-	Xsym *LSym
 }
 
 // Reloc.type

src/cmd/internal/obj/objfile.go

@@ -413,9 +413,9 @@ func writesym(ctxt *Link, b *Biobuf, s *LSym) {
 		wrint(b, int64(r.Siz))
 		wrint(b, int64(r.Type))
 		wrint(b, r.Add)
-		wrint(b, r.Xadd)
+		wrint(b, 0) // Xadd, ignored
 		wrsym(b, r.Sym)
-		wrsym(b, r.Xsym)
+		wrsym(b, nil) // Xsym, ignored
 	}
 
 	if s.Type == STEXT {

src/cmd/internal/obj/x86/asm6.go

@@ -2460,11 +2460,6 @@ func vaddr(ctxt *obj.Link, p *obj.Prog, a *obj.Addr, r *obj.Reloc) int64 {
 		r.Off = -1 // caller must fill in
 		r.Sym = s
 		r.Add = a.Offset
-		if s.Type == obj.STLSBSS {
-			r.Xadd = r.Add - int64(r.Siz)
-			r.Type = obj.R_TLS
-			r.Xsym = s
-		}
 
 		return 0
 	}