-
Than McIntosh authored
Third change of several to update the loader API to reflect the final consensus version of the loader API as described in Cherry's doc. This piece: - move objfile.Loader into its own separate package, and update clients accordingly. This includes a few minor cleanups, including converting a couple of loader-related functions to methods, and privatizing some of the loader methods such as ToGlobal/ToLocal. Change-Id: Iae20585751a45491d8b19dcffc096aadae6bbfc6 Reviewed-on: https://go-review.googlesource.com/c/go/+/200998 Run-TryBot: Than McIntosh <thanm@google.com> Reviewed-by:
Jeremy Faller <jeremy@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
Than McIntosh authoredThird change of several to update the loader API to reflect the final consensus version of the loader API as described in Cherry's doc. This piece: - move objfile.Loader into its own separate package, and update clients accordingly. This includes a few minor cleanups, including converting a couple of loader-related functions to methods, and privatizing some of the loader methods such as ToGlobal/ToLocal. Change-Id: Iae20585751a45491d8b19dcffc096aadae6bbfc6 Reviewed-on: https://go-review.googlesource.com/c/go/+/200998 Run-TryBot: Than McIntosh <thanm@google.com> Reviewed-by:
Jeremy Faller <jeremy@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
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loader.go 20.57 KiB
// Copyright 2019 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 loader
import (
"bytes"
"cmd/internal/bio"
"cmd/internal/dwarf"
"cmd/internal/goobj2"
"cmd/internal/obj"
"cmd/internal/objabi"
"cmd/internal/sys"
"cmd/link/internal/sym"
"fmt"
"log"
"os"
"sort"
"strconv"
"strings"
)
var _ = fmt.Print
// Sym encapsulates a global symbol index, used to identify a specific
// Go symbol. The 0-valued Sym is corresponds to an invalid symbol.
type Sym int
// Relocs encapsulates the set of relocations on a given symbol; an
// instance of this type is returned by the Loader Relocs() method.
type Relocs struct {
Count int // number of relocs
li int // local index of symbol whose relocs we're examining
r *oReader // object reader for containing package
l *Loader // loader
}
// Reloc contains the payload for a specific relocation.
// TODO: replace this with sym.Reloc, once we change the
// relocation target from "*sym.Symbol" to "loader.Sym" in sym.Reloc.
type Reloc struct {
Off int32 // offset to rewrite
Size uint8 // number of bytes to rewrite: 0, 1, 2, or 4
Type objabi.RelocType // the relocation type
Add int64 // addend
Sym Sym // global index of symbol the reloc addresses
}
// oReader is a wrapper type of obj.Reader, along with some
// extra information.
// TODO: rename to objReader once the old one is gone?
type oReader struct {
*goobj2.Reader
unit *sym.CompilationUnit
version int // version of static symbol
pkgprefix string
}
type objIdx struct {
r *oReader
i Sym // start index
}
type nameVer struct {
name string
v int
}
type bitmap []uint32
// set the i-th bit.
func (bm bitmap) Set(i Sym) {
n, r := uint(i)/32, uint(i)%32
bm[n] |= 1 << r
}
// whether the i-th bit is set.
func (bm bitmap) Has(i Sym) bool {
n, r := uint(i)/32, uint(i)%32
return bm[n]&(1<<r) != 0
}
func makeBitmap(n int) bitmap {
return make(bitmap, (n+31)/32)
}
// A Loader loads new object files and resolves indexed symbol references.
type Loader struct {
start map[*oReader]Sym // map from object file to its start index
objs []objIdx // sorted by start index (i.e. objIdx.i)
max Sym // current max index
extStart Sym // from this index on, the symbols are externally defined
extSyms []nameVer // externally defined symbols
symsByName map[nameVer]Sym // map symbol name to index
overwrite map[Sym]Sym // overwrite[i]=j if symbol j overwrites symbol i
objByPkg map[string]*oReader // map package path to its Go object reader
Syms []*sym.Symbol // indexed symbols. XXX we still make sym.Symbol for now.
Reachable bitmap // bitmap of reachable symbols, indexed by global index
}
func NewLoader() *Loader {
return &Loader{
start: make(map[*oReader]Sym),
objs: []objIdx{{nil, 0}},
symsByName: make(map[nameVer]Sym),
objByPkg: make(map[string]*oReader),
overwrite: make(map[Sym]Sym),
}
}
// Return the start index in the global index space for a given object file.
func (l *Loader) startIndex(r *oReader) Sym {
return l.start[r]
}
// Add object file r, return the start index.
func (l *Loader) addObj(pkg string, r *oReader) Sym {
if _, ok := l.start[r]; ok {
panic("already added")
}
pkg = objabi.PathToPrefix(pkg) // the object file contains escaped package path
if _, ok := l.objByPkg[pkg]; !ok {
l.objByPkg[pkg] = r
}
n := r.NSym() + r.NNonpkgdef()
i := l.max + 1
l.start[r] = i
l.objs = append(l.objs, objIdx{r, i})
l.max += Sym(n)
return i
}
// Add a symbol with a given index, return if it is added.
func (l *Loader) AddSym(name string, ver int, i Sym, r *oReader, dupok bool, typ sym.SymKind) bool {
if l.extStart != 0 {
panic("AddSym called after AddExtSym is called")
}
nv := nameVer{name, ver}
if oldi, ok := l.symsByName[nv]; ok {
if dupok {
return false
}
overwrite := r.DataSize(int(i-l.startIndex(r))) != 0
if overwrite {
// new symbol overwrites old symbol.
oldr, li := l.toLocal(oldi)
oldsym := goobj2.Sym{}
oldsym.Read(oldr.Reader, oldr.SymOff(li))
oldtyp := sym.AbiSymKindToSymKind[objabi.SymKind(oldsym.Type)]
if !oldsym.Dupok() && !((oldtyp == sym.SDATA || oldtyp == sym.SNOPTRDATA || oldtyp == sym.SBSS || oldtyp == sym.SNOPTRBSS) && oldr.DataSize(li) == 0) { // only allow overwriting 0-sized data symbol
log.Fatalf("duplicated definition of symbol " + name)
}
l.overwrite[oldi] = i
} else {
// old symbol overwrites new symbol.
if typ != sym.SDATA && typ != sym.SNOPTRDATA && typ != sym.SBSS && typ != sym.SNOPTRBSS { // only allow overwriting data symbol
log.Fatalf("duplicated definition of symbol " + name)
}
l.overwrite[i] = oldi
return false
}
}
l.symsByName[nv] = i
return true
}
// Add an external symbol (without index). Return the index of newly added
// symbol, or 0 if not added.
func (l *Loader) AddExtSym(name string, ver int) Sym {
nv := nameVer{name, ver}
if _, ok := l.symsByName[nv]; ok {
return 0
}
i := l.max + 1
l.symsByName[nv] = i
l.max++
if l.extStart == 0 {
l.extStart = i
}
l.extSyms = append(l.extSyms, nv)
return i
}
// Convert a local index to a global index.
func (l *Loader) toGlobal(r *oReader, i int) Sym {
g := l.startIndex(r) + Sym(i)
if ov, ok := l.overwrite[g]; ok {
return ov
}
return g
}
// Convert a global index to a local index.
func (l *Loader) toLocal(i Sym) (*oReader, int) {
if ov, ok := l.overwrite[i]; ok {
i = ov
}
if l.extStart != 0 && i >= l.extStart {
return nil, int(i - l.extStart)
}
// Search for the local object holding index i.
// Below k is the first one that has its start index > i,
// so k-1 is the one we want.
k := sort.Search(len(l.objs), func(k int) bool {
return l.objs[k].i > i
})
return l.objs[k-1].r, int(i - l.objs[k-1].i)
}
// Resolve a local symbol reference. Return global index.
func (l *Loader) resolve(r *oReader, s goobj2.SymRef) Sym {
var rr *oReader
switch p := s.PkgIdx; p {
case goobj2.PkgIdxInvalid:
if s.SymIdx != 0 {
panic("bad sym ref")
}
return 0
case goobj2.PkgIdxNone:
// Resolve by name
i := int(s.SymIdx) + r.NSym()
osym := goobj2.Sym{}
osym.Read(r.Reader, r.SymOff(i))
name := strings.Replace(osym.Name, "\"\".", r.pkgprefix, -1)
v := abiToVer(osym.ABI, r.version)
nv := nameVer{name, v}
return l.symsByName[nv]
case goobj2.PkgIdxBuiltin:
panic("PkgIdxBuiltin not used")
case goobj2.PkgIdxSelf:
rr = r
default:
pkg := r.Pkg(int(p))
var ok bool
rr, ok = l.objByPkg[pkg]
if !ok {
log.Fatalf("reference of nonexisted package %s, from %v", pkg, r.unit.Lib)
}
}
return l.toGlobal(rr, int(s.SymIdx))
}
// Look up a symbol by name, return global index, or 0 if not found.
// This is more like Syms.ROLookup than Lookup -- it doesn't create
// new symbol.
func (l *Loader) Lookup(name string, ver int) Sym {
nv := nameVer{name, ver}
return l.symsByName[nv]
}
// Number of total symbols.
func (l *Loader) NSym() int {
return int(l.max + 1)
}
// Returns the raw (unpatched) name of the i-th symbol.
func (l *Loader) RawSymName(i Sym) string {
if l.extStart != 0 && i >= l.extStart {
return ""
}
r, li := l.toLocal(i)
osym := goobj2.Sym{}
osym.Read(r.Reader, r.SymOff(li))
return osym.Name
}
// Returns the (patched) name of the i-th symbol.
func (l *Loader) SymName(i Sym) string {
if l.extStart != 0 && i >= l.extStart {
return ""
}
r, li := l.toLocal(i)
osym := goobj2.Sym{}
osym.Read(r.Reader, r.SymOff(li))
return strings.Replace(osym.Name, "\"\".", r.pkgprefix, -1)
}
// Returns the type of the i-th symbol.
func (l *Loader) SymType(i Sym) sym.SymKind {
if l.extStart != 0 && i >= l.extStart {
return 0
}
r, li := l.toLocal(i)
osym := goobj2.Sym{}
osym.Read(r.Reader, r.SymOff(li))
return sym.AbiSymKindToSymKind[objabi.SymKind(osym.Type)]
}
// Returns the attributes of the i-th symbol.
func (l *Loader) SymAttr(i Sym) uint8 {
if l.extStart != 0 && i >= l.extStart {
return 0
}
r, li := l.toLocal(i)
osym := goobj2.Sym{}
osym.Read(r.Reader, r.SymOff(li))
return osym.Flag
}
// Returns whether the i-th symbol has ReflectMethod attribute set.
func (l *Loader) IsReflectMethod(i Sym) bool {
return l.SymAttr(i)&goobj2.SymFlagReflectMethod != 0
}
// Returns the symbol content of the i-th symbol. i is global index.
func (l *Loader) Data(i Sym) []byte {
if l.extStart != 0 && i >= l.extStart {
return nil
}
r, li := l.toLocal(i)
return r.Data(li)
}
// Returns the number of aux symbols given a global index.
func (l *Loader) NAux(i Sym) int {
if l.extStart != 0 && i >= l.extStart {
return 0
}
r, li := l.toLocal(i)
return r.NAux(li)
}
// Returns the referred symbol of the j-th aux symbol of the i-th
// symbol.
func (l *Loader) AuxSym(i Sym, j int) Sym {
if l.extStart != 0 && i >= l.extStart {
return 0
}
r, li := l.toLocal(i)
a := goobj2.Aux{}
a.Read(r.Reader, r.AuxOff(li, j))
return l.resolve(r, a.Sym)
}
// Initialize Reachable bitmap for running deadcode pass.
func (l *Loader) InitReachable() {
l.Reachable = makeBitmap(l.NSym())
}
// At method returns the j-th reloc for a global symbol.
func (relocs *Relocs) At(j int) Reloc {
rel := goobj2.Reloc{}
rel.Read(relocs.r.Reader, relocs.r.RelocOff(relocs.li, j))
target := relocs.l.resolve(relocs.r, rel.Sym)
return Reloc{
Off: rel.Off,
Size: rel.Siz,
Type: objabi.RelocType(rel.Type),
Add: rel.Add,
Sym: target,
}
}
// Relocs returns a Relocs object for the given global sym.
func (l *Loader) Relocs(i Sym) Relocs {
if l.extStart != 0 && i >= l.extStart {
return Relocs{}
}
r, li := l.toLocal(i)
return l.relocs(r, li)
}
// Relocs returns a Relocs object given a local sym index and reader.
func (l *Loader) relocs(r *oReader, li int) Relocs {
return Relocs{
Count: r.NReloc(li),
li: li,
r: r,
l: l,
}
}
// Preload a package: add autolibs, add symbols to the symbol table.
// Does not read symbol data yet.
func (l *Loader) Preload(arch *sys.Arch, syms *sym.Symbols, f *bio.Reader, lib *sym.Library, unit *sym.CompilationUnit, length int64, pn string, flags int) {
roObject, readonly, err := f.Slice(uint64(length))
if err != nil {
log.Fatal("cannot read object file:", err)
}
r := goobj2.NewReaderFromBytes(roObject, readonly)
if r == nil {
panic("cannot read object file")
}
localSymVersion := syms.IncVersion()
pkgprefix := objabi.PathToPrefix(lib.Pkg) + "."
or := &oReader{r, unit, localSymVersion, pkgprefix}
// Autolib
lib.ImportStrings = append(lib.ImportStrings, r.Autolib()...)
// DWARF file table
nfile := r.NDwarfFile()
unit.DWARFFileTable = make([]string, nfile)
for i := range unit.DWARFFileTable {
unit.DWARFFileTable[i] = r.DwarfFile(i)
}
istart := l.addObj(lib.Pkg, or)
ndef := r.NSym()
nnonpkgdef := r.NNonpkgdef()
for i, n := 0, ndef+nnonpkgdef; i < n; i++ {
osym := goobj2.Sym{}
osym.Read(r, r.SymOff(i))
name := strings.Replace(osym.Name, "\"\".", pkgprefix, -1)
if name == "" {
continue // don't add unnamed aux symbol
}
v := abiToVer(osym.ABI, localSymVersion)
dupok := osym.Dupok()
l.AddSym(name, v, istart+Sym(i), or, dupok, sym.AbiSymKindToSymKind[objabi.SymKind(osym.Type)])
}
// The caller expects us consuming all the data
f.MustSeek(length, os.SEEK_CUR)
}
// Make sure referenced symbols are added. Most of them should already be added.
// This should only be needed for referenced external symbols.
func (l *Loader) LoadRefs(arch *sys.Arch, syms *sym.Symbols) {
for _, o := range l.objs[1:] {
loadObjRefs(l, o.r, arch, syms)
}
}
func loadObjRefs(l *Loader, r *oReader, arch *sys.Arch, syms *sym.Symbols) {
ndef := r.NSym() + r.NNonpkgdef()
for i, n := 0, r.NNonpkgref(); i < n; i++ {
osym := goobj2.Sym{}
osym.Read(r.Reader, r.SymOff(ndef+i))
name := strings.Replace(osym.Name, "\"\".", r.pkgprefix, -1)
v := abiToVer(osym.ABI, r.version)
l.AddExtSym(name, v)
}
}
func abiToVer(abi uint16, localSymVersion int) int {
var v int
if abi == goobj2.SymABIstatic {
// Static
v = localSymVersion
} else if abiver := sym.ABIToVersion(obj.ABI(abi)); abiver != -1 {
// Note that data symbols are "ABI0", which maps to version 0.
v = abiver
} else {
log.Fatalf("invalid symbol ABI: %d", abi)
}
return v
}
func preprocess(arch *sys.Arch, s *sym.Symbol) {
if s.Name != "" && s.Name[0] == '$' && len(s.Name) > 5 && s.Type == 0 && len(s.P) == 0 {
x, err := strconv.ParseUint(s.Name[5:], 16, 64)
if err != nil {
log.Panicf("failed to parse $-symbol %s: %v", s.Name, err)
}
s.Type = sym.SRODATA
s.Attr |= sym.AttrLocal
switch s.Name[:5] {
case "$f32.":
if uint64(uint32(x)) != x {
log.Panicf("$-symbol %s too large: %d", s.Name, x)
}
s.AddUint32(arch, uint32(x))
case "$f64.", "$i64.":
s.AddUint64(arch, x)
default:
log.Panicf("unrecognized $-symbol: %s", s.Name)
}
}
}
// Load full contents.
func (l *Loader) LoadFull(arch *sys.Arch, syms *sym.Symbols) {
// create all Symbols first.
l.Syms = make([]*sym.Symbol, l.NSym())
for _, o := range l.objs[1:] {
loadObjSyms(l, syms, o.r)
}
// external symbols
for i := l.extStart; i <= l.max; i++ {
nv := l.extSyms[i-l.extStart]
if l.Reachable.Has(i) || strings.HasPrefix(nv.name, "gofile..") { // XXX file symbols are used but not marked
s := syms.Newsym(nv.name, nv.v)
preprocess(arch, s)
s.Attr.Set(sym.AttrReachable, l.Reachable.Has(i))
l.Syms[i] = s
}
}
// load contents of defined symbols
for _, o := range l.objs[1:] {
loadObjFull(l, o.r)
}
}
func loadObjSyms(l *Loader, syms *sym.Symbols, r *oReader) {
lib := r.unit.Lib
istart := l.startIndex(r)
for i, n := 0, r.NSym()+r.NNonpkgdef(); i < n; i++ {
osym := goobj2.Sym{}
osym.Read(r.Reader, r.SymOff(i))
name := strings.Replace(osym.Name, "\"\".", r.pkgprefix, -1)
if name == "" {
continue
}
ver := abiToVer(osym.ABI, r.version)
if l.symsByName[nameVer{name, ver}] != istart+Sym(i) {
continue
}
t := sym.AbiSymKindToSymKind[objabi.SymKind(osym.Type)]
if t == sym.SXREF {
log.Fatalf("bad sxref")
}
if t == 0 {
log.Fatalf("missing type for %s in %s", name, lib)
}
if !l.Reachable.Has(istart+Sym(i)) && !(t == sym.SRODATA && strings.HasPrefix(name, "type.")) && name != "runtime.addmoduledata" && name != "runtime.lastmoduledatap" {
// No need to load unreachable symbols.
// XXX some type symbol's content may be needed in DWARF code, but they are not marked.
// XXX reference to runtime.addmoduledata may be generated later by the linker in plugin mode.
continue
}
s := syms.Newsym(name, ver)
if s.Type != 0 && s.Type != sym.SXREF {
fmt.Println("symbol already processed:", lib, i, s)
panic("symbol already processed")
}
if t == sym.SBSS && (s.Type == sym.SRODATA || s.Type == sym.SNOPTRBSS) {
t = s.Type
}
s.Type = t
s.Unit = r.unit
s.Attr.Set(sym.AttrReachable, l.Reachable.Has(istart+Sym(i)))
l.Syms[istart+Sym(i)] = s
}
}
func loadObjFull(l *Loader, r *oReader) {
lib := r.unit.Lib
istart := l.startIndex(r)
resolveSymRef := func(s goobj2.SymRef) *sym.Symbol {
i := l.resolve(r, s)
return l.Syms[i]
}
pcdataBase := r.PcdataBase()
for i, n := 0, r.NSym()+r.NNonpkgdef(); i < n; i++ {
osym := goobj2.Sym{}
osym.Read(r.Reader, r.SymOff(i))
name := strings.Replace(osym.Name, "\"\".", r.pkgprefix, -1)
if name == "" {
continue
}
ver := abiToVer(osym.ABI, r.version)
dupok := osym.Dupok()
if dupsym := l.symsByName[nameVer{name, ver}]; dupsym != istart+Sym(i) {
if dupok && l.Reachable.Has(dupsym) {
// A dupok symbol is resolved to another package. We still need
// to record its presence in the current package, as the trampoline
// pass expects packages are laid out in dependency order.
s := l.Syms[dupsym]
if s.Type == sym.STEXT {
lib.DupTextSyms = append(lib.DupTextSyms, s)
}
}
continue
}
s := l.Syms[istart+Sym(i)]
if s == nil {
continue
}
if s.Name != name { // Sanity check. We can remove it in the final version.
fmt.Println("name mismatch:", lib, i, s.Name, name)
panic("name mismatch")
}
local := osym.Local()
makeTypelink := osym.Typelink()
size := osym.Siz
// Symbol data
s.P = r.Data(i)
s.Attr.Set(sym.AttrReadOnly, r.ReadOnly())
// Relocs
relocs := l.relocs(r, i)
s.R = make([]sym.Reloc, relocs.Count)
for j := range s.R {
r := relocs.At(j)
rs := r.Sym
sz := r.Size
rt := r.Type
if rt == objabi.R_METHODOFF {
if l.Reachable.Has(rs) {
rt = objabi.R_ADDROFF
} else {
sz = 0
rs = 0
}
}
if rt == objabi.R_WEAKADDROFF && !l.Reachable.Has(rs) {
rs = 0
sz = 0
}
if rs != 0 && l.SymType(rs) == sym.SABIALIAS {
rsrelocs := l.Relocs(rs)
rs = rsrelocs.At(0).Sym
}
s.R[j] = sym.Reloc{
Off: r.Off,
Siz: sz,
Type: rt,
Add: r.Add,
Sym: l.Syms[rs],
}
}
// Aux symbol info
isym := -1
naux := r.NAux(i)
for j := 0; j < naux; j++ {
a := goobj2.Aux{}
a.Read(r.Reader, r.AuxOff(i, j))
switch a.Type {
case goobj2.AuxGotype:
typ := resolveSymRef(a.Sym)
if typ != nil {
s.Gotype = typ
}
case goobj2.AuxFuncdata:
pc := s.FuncInfo
if pc == nil {
pc = &sym.FuncInfo{Funcdata: make([]*sym.Symbol, 0, 4)}
s.FuncInfo = pc
}
pc.Funcdata = append(pc.Funcdata, resolveSymRef(a.Sym))
case goobj2.AuxFuncInfo:
if a.Sym.PkgIdx != goobj2.PkgIdxSelf {
panic("funcinfo symbol not defined in current package")
}
isym = int(a.Sym.SymIdx)
case goobj2.AuxDwarfInfo, goobj2.AuxDwarfLoc, goobj2.AuxDwarfRanges, goobj2.AuxDwarfLines:
// ignored for now
default:
panic("unknown aux type")
}
}
s.File = r.pkgprefix[:len(r.pkgprefix)-1]
if dupok {
s.Attr |= sym.AttrDuplicateOK
}
if s.Size < int64(size) {
s.Size = int64(size)
}
s.Attr.Set(sym.AttrLocal, local)
s.Attr.Set(sym.AttrMakeTypelink, makeTypelink)
if s.Type == sym.SDWARFINFO {
// For DWARF symbols, replace `"".` to actual package prefix
// in the symbol content.
// TODO: maybe we should do this in the compiler and get rid
// of this.
patchDWARFName(s, r)
}
if s.Type != sym.STEXT {
continue
}
// FuncInfo
if isym == -1 {
continue
}
b := r.Data(isym)
info := goobj2.FuncInfo{}
info.Read(b)
if info.NoSplit != 0 {
s.Attr |= sym.AttrNoSplit
}
if osym.ReflectMethod() {
s.Attr |= sym.AttrReflectMethod
}
if osym.Shared() {
s.Attr |= sym.AttrShared
}
if osym.TopFrame() {
s.Attr |= sym.AttrTopFrame
}
info.Pcdata = append(info.Pcdata, info.PcdataEnd) // for the ease of knowing where it ends
pc := s.FuncInfo
if pc == nil {
pc = &sym.FuncInfo{}
s.FuncInfo = pc
}
pc.Args = int32(info.Args)
pc.Locals = int32(info.Locals)
pc.Pcdata = make([]sym.Pcdata, len(info.Pcdata)-1) // -1 as we appended one above
pc.Funcdataoff = make([]int64, len(info.Funcdataoff))
pc.File = make([]*sym.Symbol, len(info.File))
pc.InlTree = make([]sym.InlinedCall, len(info.InlTree))
pc.Pcsp.P = r.BytesAt(pcdataBase+info.Pcsp, int(info.Pcfile-info.Pcsp))
pc.Pcfile.P = r.BytesAt(pcdataBase+info.Pcfile, int(info.Pcline-info.Pcfile))
pc.Pcline.P = r.BytesAt(pcdataBase+info.Pcline, int(info.Pcinline-info.Pcline))
pc.Pcinline.P = r.BytesAt(pcdataBase+info.Pcinline, int(info.Pcdata[0]-info.Pcinline))
for k := range pc.Pcdata {
pc.Pcdata[k].P = r.BytesAt(pcdataBase+info.Pcdata[k], int(info.Pcdata[k+1]-info.Pcdata[k]))
}
for k := range pc.Funcdataoff {
pc.Funcdataoff[k] = int64(info.Funcdataoff[k])
}
for k := range pc.File {
pc.File[k] = resolveSymRef(info.File[k])
}
for k := range pc.InlTree {
inl := &info.InlTree[k]
pc.InlTree[k] = sym.InlinedCall{
Parent: inl.Parent,
File: resolveSymRef(inl.File),
Line: inl.Line,
Func: l.SymName(l.resolve(r, inl.Func)),
ParentPC: inl.ParentPC,
}
}
if !dupok {
if s.Attr.OnList() {
log.Fatalf("symbol %s listed multiple times", s.Name)
}
s.Attr.Set(sym.AttrOnList, true)
lib.Textp = append(lib.Textp, s)
} else {
// there may ba a dup in another package
// put into a temp list and add to text later
lib.DupTextSyms = append(lib.DupTextSyms, s)
}
}
}
var emptyPkg = []byte(`"".`)
func patchDWARFName(s *sym.Symbol, r *oReader) {
// This is kind of ugly. Really the package name should not
// even be included here.
if s.Size < 1 || s.P[0] != dwarf.DW_ABRV_FUNCTION {
return
}
e := bytes.IndexByte(s.P, 0)
if e == -1 {
return
}
p := bytes.Index(s.P[:e], emptyPkg)
if p == -1 {
return
}
pkgprefix := []byte(r.pkgprefix)
patched := bytes.Replace(s.P[:e], emptyPkg, pkgprefix, -1)
s.P = append(patched, s.P[e:]...)
s.Attr.Set(sym.AttrReadOnly, false)
delta := int64(len(s.P)) - s.Size
s.Size = int64(len(s.P))
for i := range s.R {
r := &s.R[i]
if r.Off > int32(e) {
r.Off += int32(delta)
}
}
}