| // Copyright 2013 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package ld |
| |
| import ( |
| "bytes" |
| "cmd/internal/obj" |
| "fmt" |
| "log" |
| "strconv" |
| "strings" |
| ) |
| |
| const ( |
| startmagic = "\x00\x00go13ld" |
| endmagic = "\xff\xffgo13ld" |
| ) |
| |
| func ldobjfile(ctxt *Link, f *Biobuf, pkg string, length int64, pn string) { |
| start := Boffset(f) |
| ctxt.Version++ |
| var buf [8]uint8 |
| Bread(f, buf[:]) |
| if string(buf[:]) != startmagic { |
| log.Fatalf("%s: invalid file start %x %x %x %x %x %x %x %x", pn, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]) |
| } |
| c := Bgetc(f) |
| if c != 1 { |
| log.Fatalf("%s: invalid file version number %d", pn, c) |
| } |
| |
| var lib string |
| for { |
| lib = rdstring(f) |
| if lib == "" { |
| break |
| } |
| addlib(ctxt, pkg, pn, lib) |
| } |
| |
| for { |
| c = Bgetc(f) |
| Bungetc(f) |
| if c == 0xff { |
| break |
| } |
| readsym(ctxt, f, pkg, pn) |
| } |
| |
| buf = [8]uint8{} |
| Bread(f, buf[:]) |
| if string(buf[:]) != endmagic { |
| log.Fatalf("%s: invalid file end", pn) |
| } |
| |
| if Boffset(f) != start+length { |
| log.Fatalf("%s: unexpected end at %d, want %d", pn, int64(Boffset(f)), int64(start+length)) |
| } |
| } |
| |
| var readsym_ndup int |
| |
| func readsym(ctxt *Link, f *Biobuf, pkg string, pn string) { |
| if Bgetc(f) != 0xfe { |
| log.Fatalf("readsym out of sync") |
| } |
| t := int(rdint(f)) |
| name := expandpkg(rdstring(f), pkg) |
| v := int(rdint(f)) |
| if v != 0 && v != 1 { |
| log.Fatalf("invalid symbol version %d", v) |
| } |
| flags := int(rdint(f)) |
| dupok := flags & 1 |
| local := false |
| if flags&2 != 0 { |
| local = true |
| } |
| size := int(rdint(f)) |
| typ := rdsym(ctxt, f, pkg) |
| var data []byte |
| rddata(f, &data) |
| nreloc := int(rdint(f)) |
| |
| if v != 0 { |
| v = ctxt.Version |
| } |
| s := Linklookup(ctxt, name, v) |
| var dup *LSym |
| if s.Type != 0 && s.Type != obj.SXREF { |
| if (t == obj.SDATA || t == obj.SBSS || t == obj.SNOPTRBSS) && len(data) == 0 && nreloc == 0 { |
| if s.Size < int64(size) { |
| s.Size = int64(size) |
| } |
| if typ != nil && s.Gotype == nil { |
| s.Gotype = typ |
| } |
| return |
| } |
| |
| if (s.Type == obj.SDATA || s.Type == obj.SBSS || s.Type == obj.SNOPTRBSS) && len(s.P) == 0 && len(s.R) == 0 { |
| goto overwrite |
| } |
| if s.Type != obj.SBSS && s.Type != obj.SNOPTRBSS && dupok == 0 && s.Dupok == 0 { |
| log.Fatalf("duplicate symbol %s (types %d and %d) in %s and %s", s.Name, s.Type, t, s.File, pn) |
| } |
| if len(s.P) > 0 { |
| dup = s |
| s = linknewsym(ctxt, ".dup", readsym_ndup) |
| readsym_ndup++ // scratch |
| } |
| } |
| |
| overwrite: |
| s.File = pkg |
| s.Dupok = uint8(dupok) |
| if t == obj.SXREF { |
| log.Fatalf("bad sxref") |
| } |
| if t == 0 { |
| log.Fatalf("missing type for %s in %s", name, pn) |
| } |
| if t == obj.SBSS && (s.Type == obj.SRODATA || s.Type == obj.SNOPTRBSS) { |
| t = int(s.Type) |
| } |
| s.Type = int16(t) |
| if s.Size < int64(size) { |
| s.Size = int64(size) |
| } |
| s.Local = local |
| if typ != nil { // if bss sym defined multiple times, take type from any one def |
| s.Gotype = typ |
| } |
| if dup != nil && typ != nil { |
| dup.Gotype = typ |
| } |
| s.P = data |
| s.P = s.P[:len(data)] |
| if nreloc > 0 { |
| s.R = make([]Reloc, nreloc) |
| s.R = s.R[:nreloc] |
| var r *Reloc |
| for i := 0; i < nreloc; i++ { |
| r = &s.R[i] |
| r.Off = int32(rdint(f)) |
| r.Siz = uint8(rdint(f)) |
| r.Type = int32(rdint(f)) |
| r.Add = rdint(f) |
| rdint(f) // Xadd, ignored |
| r.Sym = rdsym(ctxt, f, pkg) |
| rdsym(ctxt, f, pkg) // Xsym, ignored |
| } |
| } |
| |
| if len(s.P) > 0 && dup != nil && len(dup.P) > 0 && strings.HasPrefix(s.Name, "gclocals·") { |
| // content-addressed garbage collection liveness bitmap symbol. |
| // double check for hash collisions. |
| if !bytes.Equal(s.P, dup.P) { |
| log.Fatalf("dupok hash collision for %s in %s and %s", s.Name, s.File, pn) |
| } |
| } |
| |
| if s.Type == obj.STEXT { |
| s.Args = int32(rdint(f)) |
| s.Locals = int32(rdint(f)) |
| s.Nosplit = uint8(rdint(f)) |
| v := int(rdint(f)) |
| s.Leaf = uint8(v & 1) |
| s.Cfunc = uint8(v & 2) |
| n := int(rdint(f)) |
| var a *Auto |
| for i := 0; i < n; i++ { |
| a = new(Auto) |
| a.Asym = rdsym(ctxt, f, pkg) |
| a.Aoffset = int32(rdint(f)) |
| a.Name = int16(rdint(f)) |
| a.Gotype = rdsym(ctxt, f, pkg) |
| a.Link = s.Autom |
| s.Autom = a |
| } |
| |
| s.Pcln = new(Pcln) |
| pc := s.Pcln |
| rddata(f, &pc.Pcsp.P) |
| rddata(f, &pc.Pcfile.P) |
| rddata(f, &pc.Pcline.P) |
| n = int(rdint(f)) |
| pc.Pcdata = make([]Pcdata, n) |
| pc.Npcdata = n |
| for i := 0; i < n; i++ { |
| rddata(f, &pc.Pcdata[i].P) |
| } |
| n = int(rdint(f)) |
| pc.Funcdata = make([]*LSym, n) |
| pc.Funcdataoff = make([]int64, n) |
| pc.Nfuncdata = n |
| for i := 0; i < n; i++ { |
| pc.Funcdata[i] = rdsym(ctxt, f, pkg) |
| } |
| for i := 0; i < n; i++ { |
| pc.Funcdataoff[i] = rdint(f) |
| } |
| n = int(rdint(f)) |
| pc.File = make([]*LSym, n) |
| pc.Nfile = n |
| for i := 0; i < n; i++ { |
| pc.File[i] = rdsym(ctxt, f, pkg) |
| } |
| |
| if dup == nil { |
| if s.Onlist != 0 { |
| log.Fatalf("symbol %s listed multiple times", s.Name) |
| } |
| s.Onlist = 1 |
| if ctxt.Etextp != nil { |
| ctxt.Etextp.Next = s |
| } else { |
| ctxt.Textp = s |
| } |
| ctxt.Etextp = s |
| } |
| } |
| |
| if ctxt.Debugasm != 0 { |
| fmt.Fprintf(ctxt.Bso, "%s ", s.Name) |
| if s.Version != 0 { |
| fmt.Fprintf(ctxt.Bso, "v=%d ", s.Version) |
| } |
| if s.Type != 0 { |
| fmt.Fprintf(ctxt.Bso, "t=%d ", s.Type) |
| } |
| if s.Dupok != 0 { |
| fmt.Fprintf(ctxt.Bso, "dupok ") |
| } |
| if s.Cfunc != 0 { |
| fmt.Fprintf(ctxt.Bso, "cfunc ") |
| } |
| if s.Nosplit != 0 { |
| fmt.Fprintf(ctxt.Bso, "nosplit ") |
| } |
| fmt.Fprintf(ctxt.Bso, "size=%d value=%d", int64(s.Size), int64(s.Value)) |
| if s.Type == obj.STEXT { |
| fmt.Fprintf(ctxt.Bso, " args=%#x locals=%#x", uint64(s.Args), uint64(s.Locals)) |
| } |
| fmt.Fprintf(ctxt.Bso, "\n") |
| var c int |
| var j int |
| for i := 0; i < len(s.P); { |
| fmt.Fprintf(ctxt.Bso, "\t%#04x", uint(i)) |
| for j = i; j < i+16 && j < len(s.P); j++ { |
| fmt.Fprintf(ctxt.Bso, " %02x", s.P[j]) |
| } |
| for ; j < i+16; j++ { |
| fmt.Fprintf(ctxt.Bso, " ") |
| } |
| fmt.Fprintf(ctxt.Bso, " ") |
| for j = i; j < i+16 && j < len(s.P); j++ { |
| c = int(s.P[j]) |
| if ' ' <= c && c <= 0x7e { |
| fmt.Fprintf(ctxt.Bso, "%c", c) |
| } else { |
| fmt.Fprintf(ctxt.Bso, ".") |
| } |
| } |
| |
| fmt.Fprintf(ctxt.Bso, "\n") |
| i += 16 |
| } |
| |
| var r *Reloc |
| for i := 0; i < len(s.R); i++ { |
| r = &s.R[i] |
| fmt.Fprintf(ctxt.Bso, "\trel %d+%d t=%d %s+%d\n", int(r.Off), r.Siz, r.Type, r.Sym.Name, int64(r.Add)) |
| } |
| } |
| } |
| |
| func rdint(f *Biobuf) int64 { |
| var c int |
| |
| uv := uint64(0) |
| for shift := 0; ; shift += 7 { |
| if shift >= 64 { |
| log.Fatalf("corrupt input") |
| } |
| c = Bgetc(f) |
| uv |= uint64(c&0x7F) << uint(shift) |
| if c&0x80 == 0 { |
| break |
| } |
| } |
| |
| return int64(uv>>1) ^ (int64(uint64(uv)<<63) >> 63) |
| } |
| |
| func rdstring(f *Biobuf) string { |
| n := rdint(f) |
| p := make([]byte, n) |
| Bread(f, p) |
| return string(p) |
| } |
| |
| func rddata(f *Biobuf, pp *[]byte) { |
| n := rdint(f) |
| *pp = make([]byte, n) |
| Bread(f, *pp) |
| } |
| |
| var symbuf []byte |
| |
| func rdsym(ctxt *Link, f *Biobuf, pkg string) *LSym { |
| n := int(rdint(f)) |
| if n == 0 { |
| rdint(f) |
| return nil |
| } |
| |
| if len(symbuf) < n { |
| symbuf = make([]byte, n) |
| } |
| Bread(f, symbuf[:n]) |
| p := string(symbuf[:n]) |
| v := int(rdint(f)) |
| if v != 0 { |
| v = ctxt.Version |
| } |
| s := Linklookup(ctxt, expandpkg(p, pkg), v) |
| |
| if v == 0 && s.Name[0] == '$' && s.Type == 0 { |
| if strings.HasPrefix(s.Name, "$f32.") { |
| x, _ := strconv.ParseUint(s.Name[5:], 16, 32) |
| i32 := int32(x) |
| s.Type = obj.SRODATA |
| s.Local = true |
| Adduint32(ctxt, s, uint32(i32)) |
| s.Reachable = false |
| } else if strings.HasPrefix(s.Name, "$f64.") || strings.HasPrefix(s.Name, "$i64.") { |
| x, _ := strconv.ParseUint(s.Name[5:], 16, 64) |
| i64 := int64(x) |
| s.Type = obj.SRODATA |
| s.Local = true |
| Adduint64(ctxt, s, uint64(i64)) |
| s.Reachable = false |
| } |
| } |
| if v == 0 && strings.HasPrefix(s.Name, "runtime.gcbits.0x") { |
| s.Local = true |
| } |
| return s |
| } |
