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
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
|
/* libunwind - a platform-independent unwind library
Copyright (C) 2006-2007 IBM
Contributed by
Corey Ashford <cjashfor@us.ibm.com>
Jose Flavio Aguilar Paulino <jflavio@br.ibm.com> <joseflavio@gmail.com>
This file is part of libunwind.
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. */
#include "unwind_i.h"
#include "ucontext_i.h"
#include "remote.h"
#include <signal.h>
/* This definition originates in /usr/include/asm-ppc64/ptrace.h, but is
defined there only when __KERNEL__ is defined. We reproduce it here for
our use at the user level in order to locate the ucontext record, which
appears to be at this offset relative to the stack pointer when in the
context of the signal handler return trampoline code -
__kernel_sigtramp_rt64. */
#define __SIGNAL_FRAMESIZE 128
/* This definition comes from the document "64-bit PowerPC ELF Application
Binary Interface Supplement 1.9", section 3.2.2.
http://www.linux-foundation.org/spec/ELF/ppc64/PPC-elf64abi-1.9.html#STACK */
typedef struct
{
long unsigned back_chain;
long unsigned cr_save;
long unsigned lr_save;
/* many more fields here, but they are unused by this code */
} stack_frame_t;
int
unw_step (unw_cursor_t * cursor)
{
struct cursor *c = (struct cursor *) cursor;
stack_frame_t dummy;
unw_word_t back_chain_offset, lr_save_offset, v_regs_ptr;
struct dwarf_loc back_chain_loc, lr_save_loc, sp_loc, ip_loc, v_regs_loc;
int ret, i;
Debug (1, "(cursor=%p, ip=0x%016lx)\n", c, (unsigned long) c->dwarf.ip);
/* Try DWARF-based unwinding... */
ret = dwarf_step (&c->dwarf);
if (ret < 0 && ret != -UNW_ENOINFO)
{
Debug (2, "returning %d\n", ret);
return ret;
}
if (unlikely (ret < 0))
{
if (likely (unw_is_signal_frame (cursor) <= 0))
{
/* DWARF unwinding failed. As of 09/26/2006, gcc in 64-bit mode
produces the mandatory level of traceback record in the code, but
I get the impression that this is transitory, that eventually gcc
will not produce any traceback records at all. So, for now, we
won't bother to try to find and use these records.
We can, however, attempt to unwind the frame by using the callback
chain. This is very crude, however, and won't be able to unwind
any registers besides the IP, SP, and LR . */
back_chain_offset = ((void *) &dummy.back_chain - (void *) &dummy);
lr_save_offset = ((void *) &dummy.lr_save - (void *) &dummy);
back_chain_loc = DWARF_LOC (c->dwarf.cfa + back_chain_offset, 0);
if ((ret =
dwarf_get (&c->dwarf, back_chain_loc, &c->dwarf.cfa)) < 0)
{
Debug (2,
"Unable to retrieve CFA from back chain in stack frame - %d\n",
ret);
return ret;
}
if (c->dwarf.cfa == 0)
/* Unless the cursor or stack is corrupt or uninitialized we've most
likely hit the top of the stack */
return 0;
lr_save_loc = DWARF_LOC (c->dwarf.cfa + lr_save_offset, 0);
if ((ret = dwarf_get (&c->dwarf, lr_save_loc, &c->dwarf.ip)) < 0)
{
Debug (2,
"Unable to retrieve IP from lr save in stack frame - %d\n",
ret);
return ret;
}
/* Mark all registers unsaved */
for (i = 0; i < DWARF_NUM_PRESERVED_REGS; ++i)
c->dwarf.loc[i] = DWARF_NULL_LOC;
ret = 1;
}
else
{
/* Find the sigcontext record by taking the CFA and adjusting by
the dummy signal frame size.
Note that there isn't any way to determined if SA_SIGINFO was
set in the sa_flags parameter to sigaction when the signal
handler was established. If it was not set, the ucontext
record is not required to be on the stack, in which case the
following code will likely cause a seg fault or other crash
condition. */
unw_word_t ucontext = c->dwarf.cfa + __SIGNAL_FRAMESIZE;
Debug (1, "signal frame, skip over trampoline\n");
c->sigcontext_format = PPC_SCF_LINUX_RT_SIGFRAME;
c->sigcontext_addr = ucontext;
sp_loc = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R1, 0);
ip_loc = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_NIP, 0);
ret = dwarf_get (&c->dwarf, sp_loc, &c->dwarf.cfa);
if (ret < 0)
{
Debug (2, "returning %d\n", ret);
return ret;
}
ret = dwarf_get (&c->dwarf, ip_loc, &c->dwarf.ip);
if (ret < 0)
{
Debug (2, "returning %d\n", ret);
return ret;
}
/* Instead of just restoring the non-volatile registers, do all
of the registers for now. This will incur a performance hit,
but it's rare enough not to cause too much of a problem, and
might be useful in some cases. */
c->dwarf.loc[UNW_PPC64_R0] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R0, 0);
c->dwarf.loc[UNW_PPC64_R1] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R1, 0);
c->dwarf.loc[UNW_PPC64_R2] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R2, 0);
c->dwarf.loc[UNW_PPC64_R3] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R3, 0);
c->dwarf.loc[UNW_PPC64_R4] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R4, 0);
c->dwarf.loc[UNW_PPC64_R5] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R5, 0);
c->dwarf.loc[UNW_PPC64_R6] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R6, 0);
c->dwarf.loc[UNW_PPC64_R7] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R7, 0);
c->dwarf.loc[UNW_PPC64_R8] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R8, 0);
c->dwarf.loc[UNW_PPC64_R9] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R9, 0);
c->dwarf.loc[UNW_PPC64_R10] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R10, 0);
c->dwarf.loc[UNW_PPC64_R11] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R11, 0);
c->dwarf.loc[UNW_PPC64_R12] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R12, 0);
c->dwarf.loc[UNW_PPC64_R13] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R13, 0);
c->dwarf.loc[UNW_PPC64_R14] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R14, 0);
c->dwarf.loc[UNW_PPC64_R15] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R15, 0);
c->dwarf.loc[UNW_PPC64_R16] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R16, 0);
c->dwarf.loc[UNW_PPC64_R17] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R17, 0);
c->dwarf.loc[UNW_PPC64_R18] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R18, 0);
c->dwarf.loc[UNW_PPC64_R19] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R19, 0);
c->dwarf.loc[UNW_PPC64_R20] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R20, 0);
c->dwarf.loc[UNW_PPC64_R21] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R21, 0);
c->dwarf.loc[UNW_PPC64_R22] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R22, 0);
c->dwarf.loc[UNW_PPC64_R23] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R23, 0);
c->dwarf.loc[UNW_PPC64_R24] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R24, 0);
c->dwarf.loc[UNW_PPC64_R25] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R25, 0);
c->dwarf.loc[UNW_PPC64_R26] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R26, 0);
c->dwarf.loc[UNW_PPC64_R27] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R27, 0);
c->dwarf.loc[UNW_PPC64_R28] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R28, 0);
c->dwarf.loc[UNW_PPC64_R29] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R29, 0);
c->dwarf.loc[UNW_PPC64_R30] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R30, 0);
c->dwarf.loc[UNW_PPC64_R31] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R31, 0);
c->dwarf.loc[UNW_PPC64_LR] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_LINK, 0);
c->dwarf.loc[UNW_PPC64_CTR] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_CTR, 0);
/* This CR0 assignment is probably wrong. There are 8 dwarf columns
assigned to the CR registers, but only one CR register in the
mcontext structure */
c->dwarf.loc[UNW_PPC64_CR0] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_CCR, 0);
c->dwarf.loc[UNW_PPC64_XER] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_XER, 0);
c->dwarf.loc[UNW_PPC64_NIP] =
DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_NIP, 0);
/* TODO: Is there a way of obtaining the value of the
pseudo frame pointer (which is sp + some fixed offset, I
assume), based on the contents of the ucontext record
structure? For now, set this loc to null. */
c->dwarf.loc[UNW_PPC64_FRAME_POINTER] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_F0] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R0, 0);
c->dwarf.loc[UNW_PPC64_F1] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R1, 0);
c->dwarf.loc[UNW_PPC64_F2] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R2, 0);
c->dwarf.loc[UNW_PPC64_F3] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R3, 0);
c->dwarf.loc[UNW_PPC64_F4] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R4, 0);
c->dwarf.loc[UNW_PPC64_F5] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R5, 0);
c->dwarf.loc[UNW_PPC64_F6] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R6, 0);
c->dwarf.loc[UNW_PPC64_F7] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R7, 0);
c->dwarf.loc[UNW_PPC64_F8] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R8, 0);
c->dwarf.loc[UNW_PPC64_F9] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R9, 0);
c->dwarf.loc[UNW_PPC64_F10] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R10, 0);
c->dwarf.loc[UNW_PPC64_F11] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R11, 0);
c->dwarf.loc[UNW_PPC64_F12] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R12, 0);
c->dwarf.loc[UNW_PPC64_F13] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R13, 0);
c->dwarf.loc[UNW_PPC64_F14] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R14, 0);
c->dwarf.loc[UNW_PPC64_F15] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R15, 0);
c->dwarf.loc[UNW_PPC64_F16] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R16, 0);
c->dwarf.loc[UNW_PPC64_F17] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R17, 0);
c->dwarf.loc[UNW_PPC64_F18] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R18, 0);
c->dwarf.loc[UNW_PPC64_F19] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R19, 0);
c->dwarf.loc[UNW_PPC64_F20] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R20, 0);
c->dwarf.loc[UNW_PPC64_F21] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R21, 0);
c->dwarf.loc[UNW_PPC64_F22] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R22, 0);
c->dwarf.loc[UNW_PPC64_F23] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R23, 0);
c->dwarf.loc[UNW_PPC64_F24] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R24, 0);
c->dwarf.loc[UNW_PPC64_F25] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R25, 0);
c->dwarf.loc[UNW_PPC64_F26] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R26, 0);
c->dwarf.loc[UNW_PPC64_F27] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R27, 0);
c->dwarf.loc[UNW_PPC64_F28] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R28, 0);
c->dwarf.loc[UNW_PPC64_F29] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R29, 0);
c->dwarf.loc[UNW_PPC64_F30] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R30, 0);
c->dwarf.loc[UNW_PPC64_F31] =
DWARF_LOC (ucontext + UC_MCONTEXT_FREGS_R31, 0);
/* Note that there is no .eh_section register column for the
FPSCR register. I don't know why this is. */
v_regs_loc = DWARF_LOC (ucontext + UC_MCONTEXT_V_REGS, 0);
ret = dwarf_get (&c->dwarf, v_regs_loc, &v_regs_ptr);
if (ret < 0)
{
Debug (2, "returning %d\n", ret);
return ret;
}
if (v_regs_ptr != 0)
{
/* The v_regs_ptr is not null. Set all of the AltiVec locs */
c->dwarf.loc[UNW_PPC64_V0] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R0, 0);
c->dwarf.loc[UNW_PPC64_V1] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R1, 0);
c->dwarf.loc[UNW_PPC64_V2] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R2, 0);
c->dwarf.loc[UNW_PPC64_V3] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R3, 0);
c->dwarf.loc[UNW_PPC64_V4] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R4, 0);
c->dwarf.loc[UNW_PPC64_V5] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R5, 0);
c->dwarf.loc[UNW_PPC64_V6] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R6, 0);
c->dwarf.loc[UNW_PPC64_V7] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R7, 0);
c->dwarf.loc[UNW_PPC64_V8] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R8, 0);
c->dwarf.loc[UNW_PPC64_V9] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R9, 0);
c->dwarf.loc[UNW_PPC64_V10] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R10, 0);
c->dwarf.loc[UNW_PPC64_V11] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R11, 0);
c->dwarf.loc[UNW_PPC64_V12] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R12, 0);
c->dwarf.loc[UNW_PPC64_V13] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R13, 0);
c->dwarf.loc[UNW_PPC64_V14] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R14, 0);
c->dwarf.loc[UNW_PPC64_V15] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R15, 0);
c->dwarf.loc[UNW_PPC64_V16] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R16, 0);
c->dwarf.loc[UNW_PPC64_V17] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R17, 0);
c->dwarf.loc[UNW_PPC64_V18] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R18, 0);
c->dwarf.loc[UNW_PPC64_V19] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R19, 0);
c->dwarf.loc[UNW_PPC64_V20] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R20, 0);
c->dwarf.loc[UNW_PPC64_V21] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R21, 0);
c->dwarf.loc[UNW_PPC64_V22] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R22, 0);
c->dwarf.loc[UNW_PPC64_V23] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R23, 0);
c->dwarf.loc[UNW_PPC64_V24] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R24, 0);
c->dwarf.loc[UNW_PPC64_V25] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R25, 0);
c->dwarf.loc[UNW_PPC64_V26] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R26, 0);
c->dwarf.loc[UNW_PPC64_V27] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R27, 0);
c->dwarf.loc[UNW_PPC64_V28] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R28, 0);
c->dwarf.loc[UNW_PPC64_V29] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R29, 0);
c->dwarf.loc[UNW_PPC64_V30] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R30, 0);
c->dwarf.loc[UNW_PPC64_V31] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_R31, 0);
c->dwarf.loc[UNW_PPC64_VRSAVE] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_VRSAVE, 0);
c->dwarf.loc[UNW_PPC64_VSCR] =
DWARF_LOC (v_regs_ptr + UC_MCONTEXT_VREGS_VSCR, 0);
}
else
{
c->dwarf.loc[UNW_PPC64_V0] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V1] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V2] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V3] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V4] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V5] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V6] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V7] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V8] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V9] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V10] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V11] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V12] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V13] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V14] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V15] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V16] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V17] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V18] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V19] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V20] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V21] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V22] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V23] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V24] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V25] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V26] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V27] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V28] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V29] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V30] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_V31] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_VRSAVE] = DWARF_NULL_LOC;
c->dwarf.loc[UNW_PPC64_VSCR] = DWARF_NULL_LOC;
}
ret = 1;
}
}
if (c->dwarf.ip == 0)
{
/* Unless the cursor or stack is corrupt or uninitialized,
we've most likely hit the top of the stack */
Debug (2, "returning 0\n");
return 0;
}
// on ppc64, R2 register is used as pointer to TOC
// section which is used for symbol lookup in PIC code
// ppc64 linker generates "ld r2, 40(r1)" (ELFv1) or
// "ld r2, 24(r1)" (ELFv2) instruction after each
// @plt call. We need restore R2, but only for @plt calls
{
unw_word_t ip = c->dwarf.ip;
unw_addr_space_t as = c->dwarf.as;
unw_accessors_t *a = unw_get_accessors (as);
void *arg = c->dwarf.as_arg;
uint32_t toc_save = (as->abi == UNW_PPC64_ABI_ELFv2)? 24 : 40;
int32_t inst;
if (fetch32 (as, a, &ip, &inst, arg) >= 0
&& (uint32_t)inst == (0xE8410000U + toc_save))
{
// @plt call, restoring R2 from CFA+toc_save
c->dwarf.loc[UNW_PPC64_R2] = DWARF_LOC(c->dwarf.cfa + toc_save, 0);
}
}
Debug (2, "returning %d with last return statement\n", ret);
return ret;
}
|
