aboutsummaryrefslogtreecommitdiffstats
path: root/src/libunwind.cpp
blob: c90032bd66c955c11f63717eb945b4a095cfe6fb (plain) (blame)
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
//===--------------------------- libunwind.cpp ----------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//
//  Implements unw_* functions from <libunwind.h>
//
//===----------------------------------------------------------------------===//

#include <libunwind.h>

#include "libunwind_ext.h"
#include "config.h"

#include <stdlib.h>


#if !defined(__USING_SJLJ_EXCEPTIONS__)
#include "AddressSpace.hpp"
#include "UnwindCursor.hpp"

using namespace libunwind;

/// internal object to represent this processes address space
LocalAddressSpace LocalAddressSpace::sThisAddressSpace;

_LIBUNWIND_EXPORT unw_addr_space_t unw_local_addr_space =
    (unw_addr_space_t)&LocalAddressSpace::sThisAddressSpace;

/// Create a cursor of a thread in this process given 'context' recorded by
/// __unw_getcontext().
_LIBUNWIND_HIDDEN int __unw_init_local(unw_cursor_t *cursor,
                                       unw_context_t *context) {
  _LIBUNWIND_TRACE_API("__unw_init_local(cursor=%p, context=%p)",
                       static_cast<void *>(cursor),
                       static_cast<void *>(context));
#if defined(__i386__)
# define REGISTER_KIND Registers_x86
#elif defined(__x86_64__)
# define REGISTER_KIND Registers_x86_64
#elif defined(__powerpc64__)
# define REGISTER_KIND Registers_ppc64
#elif defined(__ppc__)
# define REGISTER_KIND Registers_ppc
#elif defined(__aarch64__)
# define REGISTER_KIND Registers_arm64
#elif defined(__arm__)
# define REGISTER_KIND Registers_arm
#elif defined(__or1k__)
# define REGISTER_KIND Registers_or1k
#elif defined(__mips__) && defined(_ABIO32) && _MIPS_SIM == _ABIO32
# define REGISTER_KIND Registers_mips_o32
#elif defined(__mips64)
# define REGISTER_KIND Registers_mips_newabi
#elif defined(__mips__)
# warning The MIPS architecture is not supported with this ABI and environment!
#elif defined(__sparc__)
# define REGISTER_KIND Registers_sparc
#else
# error Architecture not supported
#endif
  // Use "placement new" to allocate UnwindCursor in the cursor buffer.
  new (reinterpret_cast<UnwindCursor<LocalAddressSpace, REGISTER_KIND> *>(cursor))
      UnwindCursor<LocalAddressSpace, REGISTER_KIND>(
          context, LocalAddressSpace::sThisAddressSpace);
#undef REGISTER_KIND
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  co->setInfoBasedOnIPRegister();

  return UNW_ESUCCESS;
}
_LIBUNWIND_WEAK_ALIAS(__unw_init_local, unw_init_local)

/// Get value of specified register at cursor position in stack frame.
_LIBUNWIND_HIDDEN int __unw_get_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
                                    unw_word_t *value) {
  _LIBUNWIND_TRACE_API("__unw_get_reg(cursor=%p, regNum=%d, &value=%p)",
                       static_cast<void *>(cursor), regNum,
                       static_cast<void *>(value));
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  if (co->validReg(regNum)) {
    *value = co->getReg(regNum);
    return UNW_ESUCCESS;
  }
  return UNW_EBADREG;
}
_LIBUNWIND_WEAK_ALIAS(__unw_get_reg, unw_get_reg)

/// Set value of specified register at cursor position in stack frame.
_LIBUNWIND_HIDDEN int __unw_set_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
                                    unw_word_t value) {
  _LIBUNWIND_TRACE_API("__unw_set_reg(cursor=%p, regNum=%d, value=0x%" PRIxPTR
                       ")",
                       static_cast<void *>(cursor), regNum, value);
  typedef LocalAddressSpace::pint_t pint_t;
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  if (co->validReg(regNum)) {
    co->setReg(regNum, (pint_t)value);
    // specical case altering IP to re-find info (being called by personality
    // function)
    if (regNum == UNW_REG_IP) {
      unw_proc_info_t info;
      // First, get the FDE for the old location and then update it.
      co->getInfo(&info);
      co->setInfoBasedOnIPRegister(false);
      // If the original call expects stack adjustment, perform this now.
      // Normal frame unwinding would have included the offset already in the
      // CFA computation.
      // Note: for PA-RISC and other platforms where the stack grows up,
      // this should actually be - info.gp. LLVM doesn't currently support
      // any such platforms and Clang doesn't export a macro for them.
      if (info.gp)
        co->setReg(UNW_REG_SP, co->getReg(UNW_REG_SP) + info.gp);
    }
    return UNW_ESUCCESS;
  }
  return UNW_EBADREG;
}
_LIBUNWIND_WEAK_ALIAS(__unw_set_reg, unw_set_reg)

/// Get value of specified float register at cursor position in stack frame.
_LIBUNWIND_HIDDEN int __unw_get_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
                                      unw_fpreg_t *value) {
  _LIBUNWIND_TRACE_API("__unw_get_fpreg(cursor=%p, regNum=%d, &value=%p)",
                       static_cast<void *>(cursor), regNum,
                       static_cast<void *>(value));
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  if (co->validFloatReg(regNum)) {
    *value = co->getFloatReg(regNum);
    return UNW_ESUCCESS;
  }
  return UNW_EBADREG;
}
_LIBUNWIND_WEAK_ALIAS(__unw_get_fpreg, unw_get_fpreg)

/// Set value of specified float register at cursor position in stack frame.
_LIBUNWIND_HIDDEN int __unw_set_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
                                      unw_fpreg_t value) {
#if defined(_LIBUNWIND_ARM_EHABI)
  _LIBUNWIND_TRACE_API("__unw_set_fpreg(cursor=%p, regNum=%d, value=%llX)",
                       static_cast<void *>(cursor), regNum, value);
#else
  _LIBUNWIND_TRACE_API("__unw_set_fpreg(cursor=%p, regNum=%d, value=%g)",
                       static_cast<void *>(cursor), regNum, value);
#endif
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  if (co->validFloatReg(regNum)) {
    co->setFloatReg(regNum, value);
    return UNW_ESUCCESS;
  }
  return UNW_EBADREG;
}
_LIBUNWIND_WEAK_ALIAS(__unw_set_fpreg, unw_set_fpreg)

/// Move cursor to next frame.
_LIBUNWIND_HIDDEN int __unw_step(unw_cursor_t *cursor) {
  _LIBUNWIND_TRACE_API("__unw_step(cursor=%p)", static_cast<void *>(cursor));
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  return co->step();
}
_LIBUNWIND_WEAK_ALIAS(__unw_step, unw_step)

/// Get unwind info at cursor position in stack frame.
_LIBUNWIND_HIDDEN int __unw_get_proc_info(unw_cursor_t *cursor,
                                          unw_proc_info_t *info) {
  _LIBUNWIND_TRACE_API("__unw_get_proc_info(cursor=%p, &info=%p)",
                       static_cast<void *>(cursor), static_cast<void *>(info));
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  co->getInfo(info);
  if (info->end_ip == 0)
    return UNW_ENOINFO;
  else
    return UNW_ESUCCESS;
}
_LIBUNWIND_WEAK_ALIAS(__unw_get_proc_info, unw_get_proc_info)

/// Resume execution at cursor position (aka longjump).
_LIBUNWIND_HIDDEN int __unw_resume(unw_cursor_t *cursor) {
  _LIBUNWIND_TRACE_API("__unw_resume(cursor=%p)", static_cast<void *>(cursor));
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  co->jumpto();
  return UNW_EUNSPEC;
}
_LIBUNWIND_WEAK_ALIAS(__unw_resume, unw_resume)

/// Get name of function at cursor position in stack frame.
_LIBUNWIND_HIDDEN int __unw_get_proc_name(unw_cursor_t *cursor, char *buf,
                                          size_t bufLen, unw_word_t *offset) {
  _LIBUNWIND_TRACE_API("__unw_get_proc_name(cursor=%p, &buf=%p, bufLen=%lu)",
                       static_cast<void *>(cursor), static_cast<void *>(buf),
                       static_cast<unsigned long>(bufLen));
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  if (co->getFunctionName(buf, bufLen, offset))
    return UNW_ESUCCESS;
  else
    return UNW_EUNSPEC;
}
_LIBUNWIND_WEAK_ALIAS(__unw_get_proc_name, unw_get_proc_name)

/// Checks if a register is a floating-point register.
_LIBUNWIND_HIDDEN int __unw_is_fpreg(unw_cursor_t *cursor,
                                     unw_regnum_t regNum) {
  _LIBUNWIND_TRACE_API("__unw_is_fpreg(cursor=%p, regNum=%d)",
                       static_cast<void *>(cursor), regNum);
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  return co->validFloatReg(regNum);
}
_LIBUNWIND_WEAK_ALIAS(__unw_is_fpreg, unw_is_fpreg)

/// Checks if a register is a floating-point register.
_LIBUNWIND_HIDDEN const char *__unw_regname(unw_cursor_t *cursor,
                                            unw_regnum_t regNum) {
  _LIBUNWIND_TRACE_API("__unw_regname(cursor=%p, regNum=%d)",
                       static_cast<void *>(cursor), regNum);
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  return co->getRegisterName(regNum);
}
_LIBUNWIND_WEAK_ALIAS(__unw_regname, unw_regname)

/// Checks if current frame is signal trampoline.
_LIBUNWIND_HIDDEN int __unw_is_signal_frame(unw_cursor_t *cursor) {
  _LIBUNWIND_TRACE_API("__unw_is_signal_frame(cursor=%p)",
                       static_cast<void *>(cursor));
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  return co->isSignalFrame();
}
_LIBUNWIND_WEAK_ALIAS(__unw_is_signal_frame, unw_is_signal_frame)

#ifdef __arm__
// Save VFP registers d0-d15 using FSTMIADX instead of FSTMIADD
_LIBUNWIND_HIDDEN void __unw_save_vfp_as_X(unw_cursor_t *cursor) {
  _LIBUNWIND_TRACE_API("__unw_get_fpreg_save_vfp_as_X(cursor=%p)",
                       static_cast<void *>(cursor));
  AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
  return co->saveVFPAsX();
}
_LIBUNWIND_WEAK_ALIAS(__unw_save_vfp_as_X, unw_save_vfp_as_X)
#endif


#if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
/// SPI: walks cached DWARF entries
_LIBUNWIND_HIDDEN void __unw_iterate_dwarf_unwind_cache(void (*func)(
    unw_word_t ip_start, unw_word_t ip_end, unw_word_t fde, unw_word_t mh)) {
  _LIBUNWIND_TRACE_API("__unw_iterate_dwarf_unwind_cache(func=%p)",
                       reinterpret_cast<void *>(func));
  DwarfFDECache<LocalAddressSpace>::iterateCacheEntries(func);
}
_LIBUNWIND_WEAK_ALIAS(__unw_iterate_dwarf_unwind_cache,
                      unw_iterate_dwarf_unwind_cache)

/// IPI: for __register_frame()
void __unw_add_dynamic_fde(unw_word_t fde) {
  CFI_Parser<LocalAddressSpace>::FDE_Info fdeInfo;
  CFI_Parser<LocalAddressSpace>::CIE_Info cieInfo;
  const char *message = CFI_Parser<LocalAddressSpace>::decodeFDE(
                           LocalAddressSpace::sThisAddressSpace,
                          (LocalAddressSpace::pint_t) fde, &fdeInfo, &cieInfo);
  if (message == NULL) {
    // dynamically registered FDEs don't have a mach_header group they are in.
    // Use fde as mh_group
    unw_word_t mh_group = fdeInfo.fdeStart;
    DwarfFDECache<LocalAddressSpace>::add((LocalAddressSpace::pint_t)mh_group,
                                          fdeInfo.pcStart, fdeInfo.pcEnd,
                                          fdeInfo.fdeStart);
  } else {
    _LIBUNWIND_DEBUG_LOG("__unw_add_dynamic_fde: bad fde: %s", message);
  }
}

/// IPI: for __deregister_frame()
void __unw_remove_dynamic_fde(unw_word_t fde) {
  // fde is own mh_group
  DwarfFDECache<LocalAddressSpace>::removeAllIn((LocalAddressSpace::pint_t)fde);
}
#endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
#endif // !defined(__USING_SJLJ_EXCEPTIONS__)



// Add logging hooks in Debug builds only
#ifndef NDEBUG
#include <stdlib.h>

_LIBUNWIND_HIDDEN
bool logAPIs() {
  // do manual lock to avoid use of _cxa_guard_acquire or initializers
  static bool checked = false;
  static bool log = false;
  if (!checked) {
    log = (getenv("LIBUNWIND_PRINT_APIS") != NULL);
    checked = true;
  }
  return log;
}

_LIBUNWIND_HIDDEN
bool logUnwinding() {
  // do manual lock to avoid use of _cxa_guard_acquire or initializers
  static bool checked = false;
  static bool log = false;
  if (!checked) {
    log = (getenv("LIBUNWIND_PRINT_UNWINDING") != NULL);
    checked = true;
  }
  return log;
}

_LIBUNWIND_HIDDEN
bool logDWARF() {
  // do manual lock to avoid use of _cxa_guard_acquire or initializers
  static bool checked = false;
  static bool log = false;
  if (!checked) {
    log = (getenv("LIBUNWIND_PRINT_DWARF") != NULL);
    checked = true;
  }
  return log;
}

#endif // NDEBUG