1 // Copyright 2019 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
10 "cmd/link/internal/sym"
14 // SymbolBuilder is a helper designed to help with the construction
15 // of new symbol contents.
16 type SymbolBuilder struct {
17 *extSymPayload // points to payload being updated
18 symIdx Sym // index of symbol being updated/constructed
22 // MakeSymbolBuilder creates a symbol builder for use in constructing
23 // an entirely new symbol.
24 func (l *Loader) MakeSymbolBuilder(name string) *SymbolBuilder {
25 // for now assume that any new sym is intended to be static
26 symIdx := l.CreateExtSym(name)
27 if l.Syms[symIdx] != nil {
28 panic("can't build if sym.Symbol already present")
30 sb := &SymbolBuilder{l: l, symIdx: symIdx}
31 sb.extSymPayload = l.getPayload(symIdx)
35 // MakeSymbolUpdater creates a symbol builder helper for an existing
36 // symbol 'symIdx'. If 'symIdx' is not an external symbol, then create
37 // a clone of it (copy name, properties, etc) fix things up so that
38 // the lookup tables and caches point to the new version, not the old
40 func (l *Loader) MakeSymbolUpdater(symIdx Sym) *SymbolBuilder {
42 panic("can't update the null symbol")
44 if !l.IsExternal(symIdx) {
45 // Create a clone with the same name/version/kind etc.
46 l.cloneToExternal(symIdx)
48 // Now that we're doing phase 2 DWARF generation using the loader
49 // but before the wavefront has reached dodata(), we can't have this
50 // assertion here. Commented out for now.
52 if l.Syms[symIdx] != nil {
53 panic(fmt.Sprintf("can't build if sym.Symbol %q already present", l.RawSymName(symIdx)))
57 // Construct updater and return.
58 sb := &SymbolBuilder{l: l, symIdx: symIdx}
59 sb.extSymPayload = l.getPayload(symIdx)
63 // Getters for properties of the symbol we're working on.
65 func (sb *SymbolBuilder) Sym() Sym { return sb.symIdx }
66 func (sb *SymbolBuilder) Name() string { return sb.name }
67 func (sb *SymbolBuilder) Version() int { return sb.ver }
68 func (sb *SymbolBuilder) Type() sym.SymKind { return sb.kind }
69 func (sb *SymbolBuilder) Size() int64 { return sb.size }
70 func (sb *SymbolBuilder) Data() []byte { return sb.data }
71 func (sb *SymbolBuilder) Value() int64 { return sb.l.SymValue(sb.symIdx) }
72 func (sb *SymbolBuilder) Align() int32 { return sb.l.SymAlign(sb.symIdx) }
73 func (sb *SymbolBuilder) Localentry() uint8 { return sb.l.SymLocalentry(sb.symIdx) }
74 func (sb *SymbolBuilder) OnList() bool { return sb.l.AttrOnList(sb.symIdx) }
75 func (sb *SymbolBuilder) External() bool { return sb.l.AttrExternal(sb.symIdx) }
76 func (sb *SymbolBuilder) Extname() string { return sb.l.SymExtname(sb.symIdx) }
77 func (sb *SymbolBuilder) CgoExportDynamic() bool { return sb.l.AttrCgoExportDynamic(sb.symIdx) }
78 func (sb *SymbolBuilder) Dynimplib() string { return sb.l.SymDynimplib(sb.symIdx) }
79 func (sb *SymbolBuilder) Dynimpvers() string { return sb.l.SymDynimpvers(sb.symIdx) }
80 func (sb *SymbolBuilder) SubSym() Sym { return sb.l.SubSym(sb.symIdx) }
81 func (sb *SymbolBuilder) GoType() Sym { return sb.l.SymGoType(sb.symIdx) }
83 // Setters for symbol properties.
85 func (sb *SymbolBuilder) SetType(kind sym.SymKind) { sb.kind = kind }
86 func (sb *SymbolBuilder) SetSize(size int64) { sb.size = size }
87 func (sb *SymbolBuilder) SetData(data []byte) { sb.data = data }
88 func (sb *SymbolBuilder) SetOnList(v bool) { sb.l.SetAttrOnList(sb.symIdx, v) }
89 func (sb *SymbolBuilder) SetExternal(v bool) { sb.l.SetAttrExternal(sb.symIdx, v) }
90 func (sb *SymbolBuilder) SetValue(v int64) { sb.l.SetSymValue(sb.symIdx, v) }
91 func (sb *SymbolBuilder) SetAlign(align int32) { sb.l.SetSymAlign(sb.symIdx, align) }
92 func (sb *SymbolBuilder) SetLocalentry(value uint8) { sb.l.SetSymLocalentry(sb.symIdx, value) }
93 func (sb *SymbolBuilder) SetExtname(value string) { sb.l.SetSymExtname(sb.symIdx, value) }
94 func (sb *SymbolBuilder) SetDynimplib(value string) { sb.l.SetSymDynimplib(sb.symIdx, value) }
95 func (sb *SymbolBuilder) SetDynimpvers(value string) { sb.l.SetSymDynimpvers(sb.symIdx, value) }
96 func (sb *SymbolBuilder) SetPlt(value int32) { sb.l.SetPlt(sb.symIdx, value) }
97 func (sb *SymbolBuilder) SetGot(value int32) { sb.l.SetGot(sb.symIdx, value) }
98 func (sb *SymbolBuilder) SetSpecial(value bool) { sb.l.SetAttrSpecial(sb.symIdx, value) }
100 func (sb *SymbolBuilder) SetNotInSymbolTable(value bool) {
101 sb.l.SetAttrNotInSymbolTable(sb.symIdx, value)
104 func (sb *SymbolBuilder) AddBytes(data []byte) {
109 sb.data = append(sb.data, data...)
110 sb.size = int64(len(sb.data))
113 func (sb *SymbolBuilder) Relocs() []Reloc {
117 func (sb *SymbolBuilder) SetRelocs(rslice []Reloc) {
121 func (sb *SymbolBuilder) WriteRelocs(rslice []Reloc) {
122 if len(sb.relocs) != len(rslice) {
123 panic("src/dest length mismatch")
125 copy(sb.relocs, rslice)
128 func (sb *SymbolBuilder) AddReloc(r Reloc) {
129 sb.relocs = append(sb.relocs, r)
132 func (sb *SymbolBuilder) Reachable() bool {
133 return sb.l.AttrReachable(sb.symIdx)
136 func (sb *SymbolBuilder) setReachable() {
137 sb.l.SetAttrReachable(sb.symIdx, true)
140 func (sb *SymbolBuilder) ReadOnly() bool {
141 return sb.l.AttrReadOnly(sb.symIdx)
144 func (sb *SymbolBuilder) SetReadOnly(v bool) {
145 sb.l.SetAttrReadOnly(sb.symIdx, v)
148 func (sb *SymbolBuilder) DuplicateOK() bool {
149 return sb.l.AttrDuplicateOK(sb.symIdx)
152 func (sb *SymbolBuilder) SetDuplicateOK(v bool) {
153 sb.l.SetAttrDuplicateOK(sb.symIdx, v)
156 func (sb *SymbolBuilder) Outer() Sym {
157 return sb.l.OuterSym(sb.symIdx)
160 func (sb *SymbolBuilder) Sub() Sym {
161 return sb.l.SubSym(sb.symIdx)
164 func (sb *SymbolBuilder) SortSub() {
165 sb.l.SortSub(sb.symIdx)
168 func (sb *SymbolBuilder) PrependSub(sub Sym) {
169 sb.l.PrependSub(sb.symIdx, sub)
172 func (sb *SymbolBuilder) AddUint8(v uint8) int64 {
179 sb.data = append(sb.data, v)
183 func (sb *SymbolBuilder) AddUintXX(arch *sys.Arch, v uint64, wid int) int64 {
186 sb.setUintXX(arch, off, v, int64(wid))
190 func (sb *SymbolBuilder) setUintXX(arch *sys.Arch, off int64, v uint64, wid int64) int64 {
194 if sb.size < off+wid {
201 sb.data[off] = uint8(v)
203 arch.ByteOrder.PutUint16(sb.data[off:], uint16(v))
205 arch.ByteOrder.PutUint32(sb.data[off:], uint32(v))
207 arch.ByteOrder.PutUint64(sb.data[off:], v)
213 func (sb *SymbolBuilder) AddUint16(arch *sys.Arch, v uint16) int64 {
214 return sb.AddUintXX(arch, uint64(v), 2)
217 func (sb *SymbolBuilder) AddUint32(arch *sys.Arch, v uint32) int64 {
218 return sb.AddUintXX(arch, uint64(v), 4)
221 func (sb *SymbolBuilder) AddUint64(arch *sys.Arch, v uint64) int64 {
222 return sb.AddUintXX(arch, v, 8)
225 func (sb *SymbolBuilder) AddUint(arch *sys.Arch, v uint64) int64 {
226 return sb.AddUintXX(arch, v, arch.PtrSize)
229 func (sb *SymbolBuilder) SetUint8(arch *sys.Arch, r int64, v uint8) int64 {
231 return sb.setUintXX(arch, r, uint64(v), 1)
234 func (sb *SymbolBuilder) SetUint16(arch *sys.Arch, r int64, v uint16) int64 {
236 return sb.setUintXX(arch, r, uint64(v), 2)
239 func (sb *SymbolBuilder) SetUint32(arch *sys.Arch, r int64, v uint32) int64 {
241 return sb.setUintXX(arch, r, uint64(v), 4)
244 func (sb *SymbolBuilder) SetUint(arch *sys.Arch, r int64, v uint64) int64 {
246 return sb.setUintXX(arch, r, v, int64(arch.PtrSize))
249 func (sb *SymbolBuilder) Addstring(str string) int64 {
252 sb.kind = sym.SNOPTRDATA
255 if sb.name == ".shstrtab" {
256 // FIXME: find a better mechanism for this
257 sb.l.elfsetstring(nil, str, int(r))
259 sb.data = append(sb.data, str...)
260 sb.data = append(sb.data, 0)
261 sb.size = int64(len(sb.data))
265 func (sb *SymbolBuilder) addRel() *Reloc {
266 sb.relocs = append(sb.relocs, Reloc{})
267 return &sb.relocs[len(sb.relocs)-1]
270 func (sb *SymbolBuilder) addAddrPlus(tgt Sym, add int64, typ objabi.RelocType, rsize int) int64 {
276 sb.size += int64(rsize)
282 r.Size = uint8(rsize)
286 return i + int64(r.Size)
289 func (sb *SymbolBuilder) AddAddrPlus(arch *sys.Arch, tgt Sym, add int64) int64 {
291 return sb.addAddrPlus(tgt, add, objabi.R_ADDR, arch.PtrSize)
294 func (sb *SymbolBuilder) AddAddrPlus4(arch *sys.Arch, tgt Sym, add int64) int64 {
296 return sb.addAddrPlus(tgt, add, objabi.R_ADDR, 4)
299 func (sb *SymbolBuilder) AddCURelativeAddrPlus(arch *sys.Arch, tgt Sym, add int64) int64 {
301 return sb.addAddrPlus(tgt, add, objabi.R_ADDRCUOFF, arch.PtrSize)