| // Inferno utils/6l/span.c |
| // http://code.google.com/p/inferno-os/source/browse/utils/6l/span.c |
| // |
| // Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved. |
| // Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net) |
| // Portions Copyright © 1997-1999 Vita Nuova Limited |
| // Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com) |
| // Portions Copyright © 2004,2006 Bruce Ellis |
| // Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net) |
| // Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others |
| // Portions Copyright © 2009 The Go Authors. All rights reserved. |
| // |
| // Permission is hereby granted, free of charge, to any person obtaining a copy |
| // of this software and associated documentation files (the "Software"), to deal |
| // in the Software without restriction, including without limitation the rights |
| // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| // copies of the Software, and to permit persons to whom the Software is |
| // furnished to do so, subject to the following conditions: |
| // |
| // The above copyright notice and this permission notice shall be included in |
| // all copies or substantial portions of the Software. |
| // |
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| // THE SOFTWARE. |
| |
| package ld |
| |
| import ( |
| "cmd/internal/obj" |
| "fmt" |
| "path/filepath" |
| "strings" |
| ) |
| |
| // Symbol table. |
| |
| func putelfstr(s string) int { |
| if len(Elfstrdat) == 0 && s != "" { |
| // first entry must be empty string |
| putelfstr("") |
| } |
| |
| // When dynamically linking, we create LSym's by reading the names from |
| // the symbol tables of the shared libraries and so the names need to |
| // match exactly. Tools like DTrace will have to wait for now. |
| if !DynlinkingGo() { |
| // Rewrite · to . for ASCII-only tools like DTrace (sigh) |
| s = strings.Replace(s, "·", ".", -1) |
| } |
| |
| n := len(s) + 1 |
| for len(Elfstrdat)+n > cap(Elfstrdat) { |
| Elfstrdat = append(Elfstrdat[:cap(Elfstrdat)], 0)[:len(Elfstrdat)] |
| } |
| |
| off := len(Elfstrdat) |
| Elfstrdat = Elfstrdat[:off+n] |
| copy(Elfstrdat[off:], s) |
| |
| return off |
| } |
| |
| func putelfsyment(off int, addr int64, size int64, info int, shndx int, other int) { |
| switch Thearch.Thechar { |
| case '6', '7', '9': |
| Thearch.Lput(uint32(off)) |
| Cput(uint8(info)) |
| Cput(uint8(other)) |
| Thearch.Wput(uint16(shndx)) |
| Thearch.Vput(uint64(addr)) |
| Thearch.Vput(uint64(size)) |
| Symsize += ELF64SYMSIZE |
| |
| default: |
| Thearch.Lput(uint32(off)) |
| Thearch.Lput(uint32(addr)) |
| Thearch.Lput(uint32(size)) |
| Cput(uint8(info)) |
| Cput(uint8(other)) |
| Thearch.Wput(uint16(shndx)) |
| Symsize += ELF32SYMSIZE |
| } |
| } |
| |
| var numelfsym int = 1 // 0 is reserved |
| |
| var elfbind int |
| |
| func putelfsym(x *LSym, s string, t int, addr int64, size int64, ver int, go_ *LSym) { |
| var type_ int |
| |
| switch t { |
| default: |
| return |
| |
| case 'T': |
| type_ = STT_FUNC |
| |
| case 'D': |
| type_ = STT_OBJECT |
| |
| case 'B': |
| type_ = STT_OBJECT |
| |
| case 'U': |
| // ElfType is only set for symbols read from Go shared libraries, but |
| // for other symbols it is left as STT_NOTYPE which is fine. |
| type_ = int(x.ElfType) |
| |
| case 't': |
| type_ = STT_TLS |
| } |
| |
| xo := x |
| for xo.Outer != nil { |
| xo = xo.Outer |
| } |
| |
| var elfshnum int |
| if xo.Type == obj.SDYNIMPORT || xo.Type == obj.SHOSTOBJ { |
| elfshnum = SHN_UNDEF |
| } else { |
| if xo.Sect == nil { |
| Ctxt.Cursym = x |
| Diag("missing section in putelfsym") |
| return |
| } |
| if xo.Sect.Elfsect == nil { |
| Ctxt.Cursym = x |
| Diag("missing ELF section in putelfsym") |
| return |
| } |
| elfshnum = xo.Sect.Elfsect.shnum |
| } |
| |
| // One pass for each binding: STB_LOCAL, STB_GLOBAL, |
| // maybe one day STB_WEAK. |
| bind := STB_GLOBAL |
| |
| if ver != 0 || (x.Type&obj.SHIDDEN != 0) || x.Local { |
| bind = STB_LOCAL |
| } |
| |
| // In external linking mode, we have to invoke gcc with -rdynamic |
| // to get the exported symbols put into the dynamic symbol table. |
| // To avoid filling the dynamic table with lots of unnecessary symbols, |
| // mark all Go symbols local (not global) in the final executable. |
| // But when we're dynamically linking, we need all those global symbols. |
| if !DynlinkingGo() && Linkmode == LinkExternal && x.Cgoexport&CgoExportStatic == 0 && elfshnum != SHN_UNDEF { |
| bind = STB_LOCAL |
| } |
| |
| if bind != elfbind { |
| return |
| } |
| |
| off := putelfstr(s) |
| if Linkmode == LinkExternal && elfshnum != SHN_UNDEF { |
| addr -= int64(xo.Sect.Vaddr) |
| } |
| other := STV_DEFAULT |
| if x.Type&obj.SHIDDEN != 0 { |
| other = STV_HIDDEN |
| } |
| putelfsyment(off, addr, size, bind<<4|type_&0xf, elfshnum, other) |
| x.Elfsym = int32(numelfsym) |
| numelfsym++ |
| } |
| |
| func putelfsectionsym(s *LSym, shndx int) { |
| putelfsyment(0, 0, 0, STB_LOCAL<<4|STT_SECTION, shndx, 0) |
| s.Elfsym = int32(numelfsym) |
| numelfsym++ |
| } |
| |
| func putelfsymshndx(sympos int64, shndx int) { |
| here := Cpos() |
| if elf64 { |
| Cseek(sympos + 6) |
| } else { |
| Cseek(sympos + 14) |
| } |
| |
| Thearch.Wput(uint16(shndx)) |
| Cseek(here) |
| } |
| |
| func Asmelfsym() { |
| // the first symbol entry is reserved |
| putelfsyment(0, 0, 0, STB_LOCAL<<4|STT_NOTYPE, 0, 0) |
| |
| dwarfaddelfsectionsyms() |
| |
| elfbind = STB_LOCAL |
| genasmsym(putelfsym) |
| |
| elfbind = STB_GLOBAL |
| elfglobalsymndx = numelfsym |
| genasmsym(putelfsym) |
| } |
| |
| func putplan9sym(x *LSym, s string, t int, addr int64, size int64, ver int, go_ *LSym) { |
| switch t { |
| case 'T', 'L', 'D', 'B': |
| if ver != 0 { |
| t += 'a' - 'A' |
| } |
| fallthrough |
| |
| case 'a', |
| 'p', |
| 'f', |
| 'z', |
| 'Z', |
| 'm': |
| l := 4 |
| if HEADTYPE == obj.Hplan9 && Thearch.Thechar == '6' && Debug['8'] == 0 { |
| Lputb(uint32(addr >> 32)) |
| l = 8 |
| } |
| |
| Lputb(uint32(addr)) |
| Cput(uint8(t + 0x80)) /* 0x80 is variable length */ |
| |
| var i int |
| if t == 'z' || t == 'Z' { |
| Cput(uint8(s[0])) |
| for i = 1; s[i] != 0 || s[i+1] != 0; i += 2 { |
| Cput(uint8(s[i])) |
| Cput(uint8(s[i+1])) |
| } |
| |
| Cput(0) |
| Cput(0) |
| i++ |
| } else { |
| /* skip the '<' in filenames */ |
| if t == 'f' { |
| s = s[1:] |
| } |
| for i = 0; i < len(s); i++ { |
| Cput(uint8(s[i])) |
| } |
| Cput(0) |
| } |
| |
| Symsize += int32(l) + 1 + int32(i) + 1 |
| |
| default: |
| return |
| } |
| } |
| |
| func Asmplan9sym() { |
| genasmsym(putplan9sym) |
| } |
| |
| var symt *LSym |
| |
| func Wputl(w uint16) { |
| Cput(uint8(w)) |
| Cput(uint8(w >> 8)) |
| } |
| |
| func Wputb(w uint16) { |
| Cput(uint8(w >> 8)) |
| Cput(uint8(w)) |
| } |
| |
| func Lputb(l uint32) { |
| Cput(uint8(l >> 24)) |
| Cput(uint8(l >> 16)) |
| Cput(uint8(l >> 8)) |
| Cput(uint8(l)) |
| } |
| |
| func Lputl(l uint32) { |
| Cput(uint8(l)) |
| Cput(uint8(l >> 8)) |
| Cput(uint8(l >> 16)) |
| Cput(uint8(l >> 24)) |
| } |
| |
| func Vputb(v uint64) { |
| Lputb(uint32(v >> 32)) |
| Lputb(uint32(v)) |
| } |
| |
| func Vputl(v uint64) { |
| Lputl(uint32(v)) |
| Lputl(uint32(v >> 32)) |
| } |
| |
| type byPkg []*Library |
| |
| func (libs byPkg) Len() int { |
| return len(libs) |
| } |
| |
| func (libs byPkg) Less(a, b int) bool { |
| return libs[a].Pkg < libs[b].Pkg |
| } |
| |
| func (libs byPkg) Swap(a, b int) { |
| libs[a], libs[b] = libs[b], libs[a] |
| } |
| |
| func symtab() { |
| dosymtype() |
| |
| // Define these so that they'll get put into the symbol table. |
| // data.c:/^address will provide the actual values. |
| xdefine("runtime.text", obj.STEXT, 0) |
| |
| xdefine("runtime.etext", obj.STEXT, 0) |
| xdefine("runtime.typelink", obj.SRODATA, 0) |
| xdefine("runtime.etypelink", obj.SRODATA, 0) |
| xdefine("runtime.rodata", obj.SRODATA, 0) |
| xdefine("runtime.erodata", obj.SRODATA, 0) |
| xdefine("runtime.noptrdata", obj.SNOPTRDATA, 0) |
| xdefine("runtime.enoptrdata", obj.SNOPTRDATA, 0) |
| xdefine("runtime.data", obj.SDATA, 0) |
| xdefine("runtime.edata", obj.SDATA, 0) |
| xdefine("runtime.bss", obj.SBSS, 0) |
| xdefine("runtime.ebss", obj.SBSS, 0) |
| xdefine("runtime.noptrbss", obj.SNOPTRBSS, 0) |
| xdefine("runtime.enoptrbss", obj.SNOPTRBSS, 0) |
| xdefine("runtime.end", obj.SBSS, 0) |
| xdefine("runtime.epclntab", obj.SRODATA, 0) |
| xdefine("runtime.esymtab", obj.SRODATA, 0) |
| |
| // garbage collection symbols |
| s := Linklookup(Ctxt, "runtime.gcdata", 0) |
| |
| s.Type = obj.SRODATA |
| s.Size = 0 |
| s.Reachable = true |
| xdefine("runtime.egcdata", obj.SRODATA, 0) |
| |
| s = Linklookup(Ctxt, "runtime.gcbss", 0) |
| s.Type = obj.SRODATA |
| s.Size = 0 |
| s.Reachable = true |
| xdefine("runtime.egcbss", obj.SRODATA, 0) |
| |
| // pseudo-symbols to mark locations of type, string, and go string data. |
| var symtype *LSym |
| var symtyperel *LSym |
| if UseRelro() && Buildmode == BuildmodeCShared { |
| s = Linklookup(Ctxt, "type.*", 0) |
| |
| s.Type = obj.STYPE |
| s.Size = 0 |
| s.Reachable = true |
| symtype = s |
| |
| s = Linklookup(Ctxt, "typerel.*", 0) |
| |
| s.Type = obj.STYPERELRO |
| s.Size = 0 |
| s.Reachable = true |
| symtyperel = s |
| } else if !DynlinkingGo() { |
| s = Linklookup(Ctxt, "type.*", 0) |
| |
| s.Type = obj.STYPE |
| s.Size = 0 |
| s.Reachable = true |
| symtype = s |
| symtyperel = s |
| } |
| |
| s = Linklookup(Ctxt, "go.string.*", 0) |
| s.Type = obj.SGOSTRING |
| s.Local = true |
| s.Size = 0 |
| s.Reachable = true |
| symgostring := s |
| |
| s = Linklookup(Ctxt, "go.func.*", 0) |
| s.Type = obj.SGOFUNC |
| s.Local = true |
| s.Size = 0 |
| s.Reachable = true |
| symgofunc := s |
| |
| s = Linklookup(Ctxt, "runtime.gcbits.*", 0) |
| s.Type = obj.SGCBITS |
| s.Local = true |
| s.Size = 0 |
| s.Reachable = true |
| symgcbits := s |
| |
| symtypelink := Linklookup(Ctxt, "runtime.typelink", 0) |
| symtypelink.Type = obj.STYPELINK |
| |
| symt = Linklookup(Ctxt, "runtime.symtab", 0) |
| symt.Local = true |
| symt.Type = obj.SSYMTAB |
| symt.Size = 0 |
| symt.Reachable = true |
| |
| ntypelinks := 0 |
| |
| // assign specific types so that they sort together. |
| // within a type they sort by size, so the .* symbols |
| // just defined above will be first. |
| // hide the specific symbols. |
| for s := Ctxt.Allsym; s != nil; s = s.Allsym { |
| if !s.Reachable || s.Special != 0 || s.Type != obj.SRODATA { |
| continue |
| } |
| |
| if strings.HasPrefix(s.Name, "type.") && !DynlinkingGo() { |
| s.Hide = 1 |
| if UseRelro() && len(s.R) > 0 { |
| s.Type = obj.STYPERELRO |
| s.Outer = symtyperel |
| } else { |
| s.Type = obj.STYPE |
| s.Outer = symtype |
| } |
| } |
| |
| if strings.HasPrefix(s.Name, "go.typelink.") { |
| ntypelinks++ |
| s.Type = obj.STYPELINK |
| s.Hide = 1 |
| s.Outer = symtypelink |
| } |
| |
| if strings.HasPrefix(s.Name, "go.string.") { |
| s.Type = obj.SGOSTRING |
| s.Hide = 1 |
| s.Outer = symgostring |
| } |
| |
| if strings.HasPrefix(s.Name, "runtime.gcbits.") { |
| s.Type = obj.SGCBITS |
| s.Hide = 1 |
| s.Outer = symgcbits |
| } |
| |
| if strings.HasPrefix(s.Name, "go.func.") { |
| s.Type = obj.SGOFUNC |
| s.Hide = 1 |
| s.Outer = symgofunc |
| } |
| |
| if strings.HasPrefix(s.Name, "gcargs.") || strings.HasPrefix(s.Name, "gclocals.") || strings.HasPrefix(s.Name, "gclocals·") { |
| s.Type = obj.SGOFUNC |
| s.Hide = 1 |
| s.Outer = symgofunc |
| s.Align = 4 |
| liveness += (s.Size + int64(s.Align) - 1) &^ (int64(s.Align) - 1) |
| } |
| } |
| |
| if Buildmode == BuildmodeShared { |
| abihashgostr := Linklookup(Ctxt, "go.link.abihash."+filepath.Base(outfile), 0) |
| abihashgostr.Reachable = true |
| abihashgostr.Type = obj.SRODATA |
| hashsym := Linklookup(Ctxt, "go.link.abihashbytes", 0) |
| Addaddr(Ctxt, abihashgostr, hashsym) |
| adduint(Ctxt, abihashgostr, uint64(hashsym.Size)) |
| } |
| |
| // Information about the layout of the executable image for the |
| // runtime to use. Any changes here must be matched by changes to |
| // the definition of moduledata in runtime/symtab.go. |
| // This code uses several global variables that are set by pcln.go:pclntab. |
| moduledata := Ctxt.Moduledata |
| // The pclntab slice |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.pclntab", 0)) |
| adduint(Ctxt, moduledata, uint64(Linklookup(Ctxt, "runtime.pclntab", 0).Size)) |
| adduint(Ctxt, moduledata, uint64(Linklookup(Ctxt, "runtime.pclntab", 0).Size)) |
| // The ftab slice |
| Addaddrplus(Ctxt, moduledata, Linklookup(Ctxt, "runtime.pclntab", 0), int64(pclntabPclntabOffset)) |
| adduint(Ctxt, moduledata, uint64(pclntabNfunc+1)) |
| adduint(Ctxt, moduledata, uint64(pclntabNfunc+1)) |
| // The filetab slice |
| Addaddrplus(Ctxt, moduledata, Linklookup(Ctxt, "runtime.pclntab", 0), int64(pclntabFiletabOffset)) |
| adduint(Ctxt, moduledata, uint64(Ctxt.Nhistfile)) |
| adduint(Ctxt, moduledata, uint64(Ctxt.Nhistfile)) |
| // findfunctab |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.findfunctab", 0)) |
| // minpc, maxpc |
| Addaddr(Ctxt, moduledata, pclntabFirstFunc) |
| Addaddrplus(Ctxt, moduledata, pclntabLastFunc, pclntabLastFunc.Size) |
| // pointers to specific parts of the module |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.text", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.etext", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.noptrdata", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.enoptrdata", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.data", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.edata", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.bss", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.ebss", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.noptrbss", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.enoptrbss", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.end", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.gcdata", 0)) |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.gcbss", 0)) |
| // The typelinks slice |
| Addaddr(Ctxt, moduledata, Linklookup(Ctxt, "runtime.typelink", 0)) |
| adduint(Ctxt, moduledata, uint64(ntypelinks)) |
| adduint(Ctxt, moduledata, uint64(ntypelinks)) |
| if len(Ctxt.Shlibs) > 0 { |
| thismodulename := filepath.Base(outfile) |
| if Buildmode == BuildmodeExe { |
| // When linking an executable, outfile is just "a.out". Make |
| // it something slightly more comprehensible. |
| thismodulename = "the executable" |
| } |
| addgostring(moduledata, "go.link.thismodulename", thismodulename) |
| |
| modulehashes := Linklookup(Ctxt, "go.link.abihashes", 0) |
| modulehashes.Reachable = true |
| modulehashes.Local = true |
| modulehashes.Type = obj.SRODATA |
| |
| for i, shlib := range Ctxt.Shlibs { |
| // modulehashes[i].modulename |
| modulename := filepath.Base(shlib.Path) |
| addgostring(modulehashes, fmt.Sprintf("go.link.libname.%d", i), modulename) |
| |
| // modulehashes[i].linktimehash |
| addgostring(modulehashes, fmt.Sprintf("go.link.linkhash.%d", i), string(shlib.Hash)) |
| |
| // modulehashes[i].runtimehash |
| abihash := Linklookup(Ctxt, "go.link.abihash."+modulename, 0) |
| abihash.Reachable = true |
| Addaddr(Ctxt, modulehashes, abihash) |
| } |
| |
| Addaddr(Ctxt, moduledata, modulehashes) |
| adduint(Ctxt, moduledata, uint64(len(Ctxt.Shlibs))) |
| adduint(Ctxt, moduledata, uint64(len(Ctxt.Shlibs))) |
| } |
| // The rest of moduledata is zero initialized. |
| // When linking an object that does not contain the runtime we are |
| // creating the moduledata from scratch and it does not have a |
| // compiler-provided size, so read it from the type data. |
| moduledatatype := Linkrlookup(Ctxt, "type.runtime.moduledata", 0) |
| moduledata.Size = decodetype_size(moduledatatype) |
| Symgrow(Ctxt, moduledata, moduledata.Size) |
| |
| lastmoduledatap := Linklookup(Ctxt, "runtime.lastmoduledatap", 0) |
| if lastmoduledatap.Type != obj.SDYNIMPORT { |
| lastmoduledatap.Type = obj.SNOPTRDATA |
| lastmoduledatap.Size = 0 // overwrite existing value |
| Addaddr(Ctxt, lastmoduledatap, moduledata) |
| } |
| } |
