1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
// Derived from Inferno utils/6l/obj.c and utils/6l/span.c
// https://bitbucket.org/inferno-os/inferno-os/src/master/utils/6l/obj.c
// https://bitbucket.org/inferno-os/inferno-os/src/master/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 obj
import (
"cmd/internal/objabi"
"log"
"math"
)
// Grow increases the length of s.P to lsiz.
func (s *LSym) Grow(lsiz int64) {
siz := int(lsiz)
if int64(siz) != lsiz {
log.Fatalf("LSym.Grow size %d too long", lsiz)
}
if len(s.P) >= siz {
return
}
s.P = append(s.P, make([]byte, siz-len(s.P))...)
}
// GrowCap increases the capacity of s.P to c.
func (s *LSym) GrowCap(c int64) {
if int64(cap(s.P)) >= c {
return
}
if s.P == nil {
s.P = make([]byte, 0, c)
return
}
b := make([]byte, len(s.P), c)
copy(b, s.P)
s.P = b
}
// prepwrite prepares to write data of size siz into s at offset off.
func (s *LSym) prepwrite(ctxt *Link, off int64, siz int) {
if off < 0 || siz < 0 || off >= 1<<30 {
ctxt.Diag("prepwrite: bad off=%d siz=%d s=%v", off, siz, s)
}
switch s.Type {
case objabi.Sxxx, objabi.SBSS:
s.Type = objabi.SDATA
case objabi.SNOPTRBSS:
s.Type = objabi.SNOPTRDATA
case objabi.STLSBSS:
ctxt.Diag("cannot supply data for %v var %v", s.Type, s.Name)
}
l := off + int64(siz)
s.Grow(l)
if l > s.Size {
s.Size = l
}
}
// WriteFloat32 writes f into s at offset off.
func (s *LSym) WriteFloat32(ctxt *Link, off int64, f float32) {
s.prepwrite(ctxt, off, 4)
ctxt.Arch.ByteOrder.PutUint32(s.P[off:], math.Float32bits(f))
}
// WriteFloat64 writes f into s at offset off.
func (s *LSym) WriteFloat64(ctxt *Link, off int64, f float64) {
s.prepwrite(ctxt, off, 8)
ctxt.Arch.ByteOrder.PutUint64(s.P[off:], math.Float64bits(f))
}
// WriteInt writes an integer i of size siz into s at offset off.
func (s *LSym) WriteInt(ctxt *Link, off int64, siz int, i int64) {
s.prepwrite(ctxt, off, siz)
switch siz {
default:
ctxt.Diag("WriteInt: bad integer size: %d", siz)
case 1:
s.P[off] = byte(i)
case 2:
ctxt.Arch.ByteOrder.PutUint16(s.P[off:], uint16(i))
case 4:
ctxt.Arch.ByteOrder.PutUint32(s.P[off:], uint32(i))
case 8:
ctxt.Arch.ByteOrder.PutUint64(s.P[off:], uint64(i))
}
}
func (s *LSym) writeAddr(ctxt *Link, off int64, siz int, rsym *LSym, roff int64, rtype objabi.RelocType) {
// Allow 4-byte addresses for DWARF.
if siz != ctxt.Arch.PtrSize && siz != 4 {
ctxt.Diag("WriteAddr: bad address size %d in %s", siz, s.Name)
}
s.prepwrite(ctxt, off, siz)
r := Addrel(s)
r.Off = int32(off)
if int64(r.Off) != off {
ctxt.Diag("WriteAddr: off overflow %d in %s", off, s.Name)
}
r.Siz = uint8(siz)
r.Sym = rsym
r.Type = rtype
r.Add = roff
}
// WriteAddr writes an address of size siz into s at offset off.
// rsym and roff specify the relocation for the address.
func (s *LSym) WriteAddr(ctxt *Link, off int64, siz int, rsym *LSym, roff int64) {
s.writeAddr(ctxt, off, siz, rsym, roff, objabi.R_ADDR)
}
// WriteWeakAddr writes an address of size siz into s at offset off.
// rsym and roff specify the relocation for the address.
// This is a weak reference.
func (s *LSym) WriteWeakAddr(ctxt *Link, off int64, siz int, rsym *LSym, roff int64) {
s.writeAddr(ctxt, off, siz, rsym, roff, objabi.R_WEAKADDR)
}
// WriteCURelativeAddr writes a pointer-sized address into s at offset off.
// rsym and roff specify the relocation for the address which will be
// resolved by the linker to an offset from the DW_AT_low_pc attribute of
// the DWARF Compile Unit of rsym.
func (s *LSym) WriteCURelativeAddr(ctxt *Link, off int64, rsym *LSym, roff int64) {
s.writeAddr(ctxt, off, ctxt.Arch.PtrSize, rsym, roff, objabi.R_ADDRCUOFF)
}
// WriteOff writes a 4 byte offset to rsym+roff into s at offset off.
// After linking the 4 bytes stored at s+off will be
// rsym+roff-(start of section that s is in).
func (s *LSym) WriteOff(ctxt *Link, off int64, rsym *LSym, roff int64) {
s.prepwrite(ctxt, off, 4)
r := Addrel(s)
r.Off = int32(off)
if int64(r.Off) != off {
ctxt.Diag("WriteOff: off overflow %d in %s", off, s.Name)
}
r.Siz = 4
r.Sym = rsym
r.Type = objabi.R_ADDROFF
r.Add = roff
}
// WriteWeakOff writes a weak 4 byte offset to rsym+roff into s at offset off.
// After linking the 4 bytes stored at s+off will be
// rsym+roff-(start of section that s is in).
func (s *LSym) WriteWeakOff(ctxt *Link, off int64, rsym *LSym, roff int64) {
s.prepwrite(ctxt, off, 4)
r := Addrel(s)
r.Off = int32(off)
if int64(r.Off) != off {
ctxt.Diag("WriteOff: off overflow %d in %s", off, s.Name)
}
r.Siz = 4
r.Sym = rsym
r.Type = objabi.R_WEAKADDROFF
r.Add = roff
}
// WriteString writes a string of size siz into s at offset off.
func (s *LSym) WriteString(ctxt *Link, off int64, siz int, str string) {
if siz < len(str) {
ctxt.Diag("WriteString: bad string size: %d < %d", siz, len(str))
}
s.prepwrite(ctxt, off, siz)
copy(s.P[off:off+int64(siz)], str)
}
// WriteBytes writes a slice of bytes into s at offset off.
func (s *LSym) WriteBytes(ctxt *Link, off int64, b []byte) int64 {
s.prepwrite(ctxt, off, len(b))
copy(s.P[off:], b)
return off + int64(len(b))
}
func Addrel(s *LSym) *Reloc {
if s.R == nil {
s.R = make([]Reloc, 0, 4)
}
s.R = append(s.R, Reloc{})
return &s.R[len(s.R)-1]
}
|
