[dev.link] cmd/link: remove ARM64 special handling of GC data in shared libraries

The special case is no longer needed, didn't actually work, and
we no longer even save this map anywhere (see CL 240621 for more
information).

Change-Id: I19bcf32cace22decf50fd6414d4519cc51cbb0be
Reviewed-on: https://go-review.googlesource.com/c/go/+/241982
Reviewed-by: Austin Clements <austin@google.com>

diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go
index 4121124eb0d7afae81ea42c650a1704138bce06e..a489da02bc95a720f4bab673706614f7ed73419d 100644 (file)
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -2038,7 +2038,6 @@ func ldshlibsyms(ctxt *Link, shlib string) {
                Errorf(nil, "cannot read symbols from shared library: %s", libpath)
                return
        }
-       gcdataLocations := make(map[uint64]loader.Sym)
        for _, elfsym := range syms {
                if elf.ST_TYPE(elfsym.Info) == elf.STT_NOTYPE || elf.ST_TYPE(elfsym.Info) == elf.STT_SECTION {
                        continue
@@ -2085,7 +2084,6 @@ func ldshlibsyms(ctxt *Link, shlib string) {
                        sname := l.SymName(s)
                        if strings.HasPrefix(sname, "type.") && !strings.HasPrefix(sname, "type..") {
                                su.SetData(readelfsymboldata(ctxt, f, &elfsym))
-                               gcdataLocations[elfsym.Value+2*uint64(ctxt.Arch.PtrSize)+8+1*uint64(ctxt.Arch.PtrSize)] = s
                        }
                }
 
@@ -2106,28 +2104,6 @@ func ldshlibsyms(ctxt *Link, shlib string) {
                        su.AddReloc(loader.Reloc{Sym: s})
                }
        }
-       if ctxt.Arch.Family == sys.ARM64 {
-               for _, sect := range f.Sections {
-                       if sect.Type == elf.SHT_RELA {
-                               var rela elf.Rela64
-                               rdr := sect.Open()
-                               for {
-                                       err := binary.Read(rdr, f.ByteOrder, &rela)
-                                       if err == io.EOF {
-                                               break
-                                       } else if err != nil {
-                                               Errorf(nil, "reading relocation failed %v", err)
-                                               return
-                                       }
-                                       t := elf.R_AARCH64(rela.Info & 0xffff)
-                                       if t != elf.R_AARCH64_RELATIVE {
-                                               continue
-                                       }
-                               }
-                       }
-               }
-       }
-
        ctxt.Shlibs = append(ctxt.Shlibs, Shlib{Path: libpath, Hash: hash, Deps: deps, File: f})
 }