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
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
|
// -*- C++ -*- The GNU C++ exception personality routine.
// Copyright (C) 2001-2019 Free Software Foundation, Inc.
//
// This file is part of GCC.
//
// GCC is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3, or (at your option)
// any later version.
//
// GCC is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
#include <bits/c++config.h>
#include <cstdlib>
#include <bits/exception_defines.h>
#include <cxxabi.h>
#include "unwind-cxx.h"
using namespace __cxxabiv1;
#include "unwind-pe.h"
struct lsda_header_info
{
_Unwind_Ptr Start;
_Unwind_Ptr LPStart;
_Unwind_Ptr ttype_base;
const unsigned char *TType;
const unsigned char *action_table;
unsigned char ttype_encoding;
unsigned char call_site_encoding;
};
static const unsigned char *
parse_lsda_header (_Unwind_Context *context, const unsigned char *p,
lsda_header_info *info)
{
_uleb128_t tmp;
unsigned char lpstart_encoding;
info->Start = (context ? _Unwind_GetRegionStart (context) : 0);
// Find @LPStart, the base to which landing pad offsets are relative.
lpstart_encoding = *p++;
if (lpstart_encoding != DW_EH_PE_omit)
p = read_encoded_value (context, lpstart_encoding, p, &info->LPStart);
else
info->LPStart = info->Start;
// Find @TType, the base of the handler and exception spec type data.
info->ttype_encoding = *p++;
if (info->ttype_encoding != DW_EH_PE_omit)
{
#if _GLIBCXX_OVERRIDE_TTYPE_ENCODING
/* Older ARM EABI toolchains set this value incorrectly, so use a
hardcoded OS-specific format. */
info->ttype_encoding = _GLIBCXX_OVERRIDE_TTYPE_ENCODING;
#endif
p = read_uleb128 (p, &tmp);
info->TType = p + tmp;
}
else
info->TType = 0;
// The encoding and length of the call-site table; the action table
// immediately follows.
info->call_site_encoding = *p++;
p = read_uleb128 (p, &tmp);
info->action_table = p + tmp;
return p;
}
// Return an element from a type table.
static const std::type_info *
get_ttype_entry (lsda_header_info *info, _uleb128_t i)
{
_Unwind_Ptr ptr;
i *= size_of_encoded_value (info->ttype_encoding);
read_encoded_value_with_base (info->ttype_encoding, info->ttype_base,
info->TType - i, &ptr);
return reinterpret_cast<const std::type_info *>(ptr);
}
#ifdef __ARM_EABI_UNWINDER__
// The ABI provides a routine for matching exception object types.
typedef _Unwind_Control_Block _throw_typet;
#define get_adjusted_ptr(catch_type, throw_type, thrown_ptr_p) \
(__cxa_type_match (throw_type, catch_type, false, thrown_ptr_p) \
!= ctm_failed)
// Return true if THROW_TYPE matches one if the filter types.
static bool
check_exception_spec(lsda_header_info* info, _throw_typet* throw_type,
void* thrown_ptr, _sleb128_t filter_value)
{
const _uleb128_t* e = ((const _uleb128_t*) info->TType)
- filter_value - 1;
while (1)
{
const std::type_info* catch_type;
_uleb128_t tmp;
tmp = *e;
// Zero signals the end of the list. If we've not found
// a match by now, then we've failed the specification.
if (tmp == 0)
return false;
tmp = _Unwind_decode_typeinfo_ptr(info->ttype_base, (_Unwind_Word) e);
// Match a ttype entry.
catch_type = reinterpret_cast<const std::type_info*>(tmp);
// ??? There is currently no way to ask the RTTI code about the
// relationship between two types without reference to a specific
// object. There should be; then we wouldn't need to mess with
// thrown_ptr here.
if (get_adjusted_ptr(catch_type, throw_type, &thrown_ptr))
return true;
// Advance to the next entry.
e++;
}
}
// Save stage1 handler information in the exception object
static inline void
save_caught_exception(struct _Unwind_Exception* ue_header,
struct _Unwind_Context* context,
void* thrown_ptr,
int handler_switch_value,
const unsigned char* language_specific_data,
_Unwind_Ptr landing_pad,
const unsigned char* action_record
__attribute__((__unused__)))
{
ue_header->barrier_cache.sp = _Unwind_GetGR(context, UNWIND_STACK_REG);
ue_header->barrier_cache.bitpattern[0] = (_uw) thrown_ptr;
ue_header->barrier_cache.bitpattern[1]
= (_uw) handler_switch_value;
ue_header->barrier_cache.bitpattern[2]
= (_uw) language_specific_data;
ue_header->barrier_cache.bitpattern[3] = (_uw) landing_pad;
}
// Restore the catch handler data saved during phase1.
static inline void
restore_caught_exception(struct _Unwind_Exception* ue_header,
int& handler_switch_value,
const unsigned char*& language_specific_data,
_Unwind_Ptr& landing_pad)
{
handler_switch_value = (int) ue_header->barrier_cache.bitpattern[1];
language_specific_data =
(const unsigned char*) ue_header->barrier_cache.bitpattern[2];
landing_pad = (_Unwind_Ptr) ue_header->barrier_cache.bitpattern[3];
}
#define CONTINUE_UNWINDING \
do \
{ \
if (__gnu_unwind_frame(ue_header, context) != _URC_OK) \
return _URC_FAILURE; \
return _URC_CONTINUE_UNWIND; \
} \
while (0)
// Return true if the filter spec is empty, ie throw().
static bool
empty_exception_spec (lsda_header_info *info, _Unwind_Sword filter_value)
{
const _Unwind_Word* e = ((const _Unwind_Word*) info->TType)
- filter_value - 1;
return *e == 0;
}
#else
typedef const std::type_info _throw_typet;
// Given the thrown type THROW_TYPE, pointer to a variable containing a
// pointer to the exception object THROWN_PTR_P and a type CATCH_TYPE to
// compare against, return whether or not there is a match and if so,
// update *THROWN_PTR_P.
static bool
get_adjusted_ptr (const std::type_info *catch_type,
const std::type_info *throw_type,
void **thrown_ptr_p)
{
void *thrown_ptr = *thrown_ptr_p;
// Pointer types need to adjust the actual pointer, not
// the pointer to pointer that is the exception object.
// This also has the effect of passing pointer types
// "by value" through the __cxa_begin_catch return value.
if (throw_type->__is_pointer_p ())
thrown_ptr = *(void **) thrown_ptr;
if (catch_type->__do_catch (throw_type, &thrown_ptr, 1))
{
*thrown_ptr_p = thrown_ptr;
return true;
}
return false;
}
// Return true if THROW_TYPE matches one if the filter types.
static bool
check_exception_spec(lsda_header_info* info, _throw_typet* throw_type,
void* thrown_ptr, _sleb128_t filter_value)
{
const unsigned char *e = info->TType - filter_value - 1;
while (1)
{
const std::type_info *catch_type;
_uleb128_t tmp;
e = read_uleb128 (e, &tmp);
// Zero signals the end of the list. If we've not found
// a match by now, then we've failed the specification.
if (tmp == 0)
return false;
// Match a ttype entry.
catch_type = get_ttype_entry (info, tmp);
// ??? There is currently no way to ask the RTTI code about the
// relationship between two types without reference to a specific
// object. There should be; then we wouldn't need to mess with
// thrown_ptr here.
if (get_adjusted_ptr (catch_type, throw_type, &thrown_ptr))
return true;
}
}
// Save stage1 handler information in the exception object
static inline void
save_caught_exception(struct _Unwind_Exception* ue_header,
struct _Unwind_Context* context
__attribute__((__unused__)),
void* thrown_ptr,
int handler_switch_value,
const unsigned char* language_specific_data,
_Unwind_Ptr landing_pad __attribute__((__unused__)),
const unsigned char* action_record)
{
__cxa_exception* xh = __get_exception_header_from_ue(ue_header);
xh->handlerSwitchValue = handler_switch_value;
xh->actionRecord = action_record;
xh->languageSpecificData = language_specific_data;
xh->adjustedPtr = thrown_ptr;
// ??? Completely unknown what this field is supposed to be for.
// ??? Need to cache TType encoding base for call_unexpected.
xh->catchTemp = landing_pad;
}
// Restore the catch handler information saved during phase1.
static inline void
restore_caught_exception(struct _Unwind_Exception* ue_header,
int& handler_switch_value,
const unsigned char*& language_specific_data,
_Unwind_Ptr& landing_pad)
{
__cxa_exception* xh = __get_exception_header_from_ue(ue_header);
handler_switch_value = xh->handlerSwitchValue;
language_specific_data = xh->languageSpecificData;
landing_pad = (_Unwind_Ptr) xh->catchTemp;
}
#define CONTINUE_UNWINDING return _URC_CONTINUE_UNWIND
// Return true if the filter spec is empty, ie throw().
static bool
empty_exception_spec (lsda_header_info *info, _Unwind_Sword filter_value)
{
const unsigned char *e = info->TType - filter_value - 1;
_uleb128_t tmp;
e = read_uleb128 (e, &tmp);
return tmp == 0;
}
#endif // !__ARM_EABI_UNWINDER__
namespace __cxxabiv1
{
// Using a different personality function name causes link failures
// when trying to mix code using different exception handling models.
#ifdef __USING_SJLJ_EXCEPTIONS__
#define PERSONALITY_FUNCTION __gxx_personality_sj0
#define __builtin_eh_return_data_regno(x) x
#elif defined(__SEH__)
#define PERSONALITY_FUNCTION __gxx_personality_imp
#else
#define PERSONALITY_FUNCTION __gxx_personality_v0
#endif
#if defined (__SEH__) && !defined (__USING_SJLJ_EXCEPTIONS__)
static
#else
extern "C"
#endif
_Unwind_Reason_Code
#ifdef __ARM_EABI_UNWINDER__
PERSONALITY_FUNCTION (_Unwind_State state,
struct _Unwind_Exception* ue_header,
struct _Unwind_Context* context)
#else
PERSONALITY_FUNCTION (int version,
_Unwind_Action actions,
_Unwind_Exception_Class exception_class,
struct _Unwind_Exception *ue_header,
struct _Unwind_Context *context)
#endif
{
enum found_handler_type
{
found_nothing,
found_terminate,
found_cleanup,
found_handler
} found_type;
lsda_header_info info;
const unsigned char *language_specific_data;
const unsigned char *action_record;
const unsigned char *p;
_Unwind_Ptr landing_pad, ip;
int handler_switch_value;
void* thrown_ptr = 0;
bool foreign_exception;
int ip_before_insn = 0;
#ifdef __ARM_EABI_UNWINDER__
_Unwind_Action actions;
switch (state & _US_ACTION_MASK)
{
case _US_VIRTUAL_UNWIND_FRAME:
// If the unwind state pattern is
// _US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND
// then we don't need to search for any handler as it is not a real
// exception. Just unwind the stack.
if (state & _US_FORCE_UNWIND)
CONTINUE_UNWINDING;
actions = _UA_SEARCH_PHASE;
break;
case _US_UNWIND_FRAME_STARTING:
actions = _UA_CLEANUP_PHASE;
if (!(state & _US_FORCE_UNWIND)
&& ue_header->barrier_cache.sp == _Unwind_GetGR(context,
UNWIND_STACK_REG))
actions |= _UA_HANDLER_FRAME;
break;
case _US_UNWIND_FRAME_RESUME:
CONTINUE_UNWINDING;
break;
default:
std::abort();
}
actions |= state & _US_FORCE_UNWIND;
// We don't know which runtime we're working with, so can't check this.
// However the ABI routines hide this from us, and we don't actually need
// to know.
foreign_exception = false;
// The dwarf unwinder assumes the context structure holds things like the
// function and LSDA pointers. The ARM implementation caches these in
// the exception header (UCB). To avoid rewriting everything we make a
// virtual scratch register point at the UCB.
ip = (_Unwind_Ptr) ue_header;
_Unwind_SetGR(context, UNWIND_POINTER_REG, ip);
#else
__cxa_exception* xh = __get_exception_header_from_ue(ue_header);
// Interface version check.
if (version != 1)
return _URC_FATAL_PHASE1_ERROR;
foreign_exception = !__is_gxx_exception_class(exception_class);
#endif
// Shortcut for phase 2 found handler for domestic exception.
if (actions == (_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME)
&& !foreign_exception)
{
restore_caught_exception(ue_header, handler_switch_value,
language_specific_data, landing_pad);
found_type = (landing_pad == 0 ? found_terminate : found_handler);
goto install_context;
}
language_specific_data = (const unsigned char *)
_Unwind_GetLanguageSpecificData (context);
// If no LSDA, then there are no handlers or cleanups.
if (! language_specific_data)
CONTINUE_UNWINDING;
// Parse the LSDA header.
p = parse_lsda_header (context, language_specific_data, &info);
info.ttype_base = base_of_encoded_value (info.ttype_encoding, context);
#ifdef _GLIBCXX_HAVE_GETIPINFO
ip = _Unwind_GetIPInfo (context, &ip_before_insn);
#else
ip = _Unwind_GetIP (context);
#endif
if (! ip_before_insn)
--ip;
landing_pad = 0;
action_record = 0;
handler_switch_value = 0;
#ifdef __USING_SJLJ_EXCEPTIONS__
// The given "IP" is an index into the call-site table, with two
// exceptions -- -1 means no-action, and 0 means terminate. But
// since we're using uleb128 values, we've not got random access
// to the array.
if ((int) ip < 0)
return _URC_CONTINUE_UNWIND;
else if (ip == 0)
{
// Fall through to set found_terminate.
}
else
{
_uleb128_t cs_lp, cs_action;
do
{
p = read_uleb128 (p, &cs_lp);
p = read_uleb128 (p, &cs_action);
}
while (--ip);
// Can never have null landing pad for sjlj -- that would have
// been indicated by a -1 call site index.
landing_pad = cs_lp + 1;
if (cs_action)
action_record = info.action_table + cs_action - 1;
goto found_something;
}
#else
// Search the call-site table for the action associated with this IP.
while (p < info.action_table)
{
_Unwind_Ptr cs_start, cs_len, cs_lp;
_uleb128_t cs_action;
// Note that all call-site encodings are "absolute" displacements.
p = read_encoded_value (0, info.call_site_encoding, p, &cs_start);
p = read_encoded_value (0, info.call_site_encoding, p, &cs_len);
p = read_encoded_value (0, info.call_site_encoding, p, &cs_lp);
p = read_uleb128 (p, &cs_action);
// The table is sorted, so if we've passed the ip, stop.
if (ip < info.Start + cs_start)
p = info.action_table;
else if (ip < info.Start + cs_start + cs_len)
{
if (cs_lp)
landing_pad = info.LPStart + cs_lp;
if (cs_action)
action_record = info.action_table + cs_action - 1;
goto found_something;
}
}
#endif // __USING_SJLJ_EXCEPTIONS__
// If ip is not present in the table, call terminate. This is for
// a destructor inside a cleanup, or a library routine the compiler
// was not expecting to throw.
found_type = found_terminate;
goto do_something;
found_something:
if (landing_pad == 0)
{
// If ip is present, and has a null landing pad, there are
// no cleanups or handlers to be run.
found_type = found_nothing;
}
else if (action_record == 0)
{
// If ip is present, has a non-null landing pad, and a null
// action table offset, then there are only cleanups present.
// Cleanups use a zero switch value, as set above.
found_type = found_cleanup;
}
else
{
// Otherwise we have a catch handler or exception specification.
_sleb128_t ar_filter, ar_disp;
const std::type_info* catch_type;
_throw_typet* throw_type;
bool saw_cleanup = false;
bool saw_handler = false;
#ifdef __ARM_EABI_UNWINDER__
// ??? How does this work - more importantly, how does it interact with
// dependent exceptions?
throw_type = ue_header;
if (actions & _UA_FORCE_UNWIND)
{
__GXX_INIT_FORCED_UNWIND_CLASS(ue_header->exception_class);
}
else if (!foreign_exception)
thrown_ptr = __get_object_from_ue (ue_header);
#else
#if __cpp_rtti
// During forced unwinding, match a magic exception type.
if (actions & _UA_FORCE_UNWIND)
{
throw_type = &typeid(abi::__forced_unwind);
}
// With a foreign exception class, there's no exception type.
// ??? What to do about GNU Java and GNU Ada exceptions?
else if (foreign_exception)
{
throw_type = &typeid(abi::__foreign_exception);
}
else
#endif
{
thrown_ptr = __get_object_from_ue (ue_header);
throw_type = __get_exception_header_from_obj
(thrown_ptr)->exceptionType;
}
#endif
while (1)
{
p = action_record;
p = read_sleb128 (p, &ar_filter);
read_sleb128 (p, &ar_disp);
if (ar_filter == 0)
{
// Zero filter values are cleanups.
saw_cleanup = true;
}
else if (ar_filter > 0)
{
// Positive filter values are handlers.
catch_type = get_ttype_entry (&info, ar_filter);
// Null catch type is a catch-all handler; we can catch foreign
// exceptions with this. Otherwise we must match types.
if (! catch_type
|| (throw_type
&& get_adjusted_ptr (catch_type, throw_type,
&thrown_ptr)))
{
saw_handler = true;
break;
}
}
else
{
// Negative filter values are exception specifications.
// ??? How do foreign exceptions fit in? As far as I can
// see we can't match because there's no __cxa_exception
// object to stuff bits in for __cxa_call_unexpected to use.
// Allow them iff the exception spec is non-empty. I.e.
// a throw() specification results in __unexpected.
if ((throw_type
&& !(actions & _UA_FORCE_UNWIND)
&& !foreign_exception)
? ! check_exception_spec (&info, throw_type, thrown_ptr,
ar_filter)
: empty_exception_spec (&info, ar_filter))
{
saw_handler = true;
break;
}
}
if (ar_disp == 0)
break;
action_record = p + ar_disp;
}
if (saw_handler)
{
handler_switch_value = ar_filter;
found_type = found_handler;
}
else
found_type = (saw_cleanup ? found_cleanup : found_nothing);
}
do_something:
if (found_type == found_nothing)
CONTINUE_UNWINDING;
if (actions & _UA_SEARCH_PHASE)
{
if (found_type == found_cleanup)
CONTINUE_UNWINDING;
// For domestic exceptions, we cache data from phase 1 for phase 2.
if (!foreign_exception)
{
save_caught_exception(ue_header, context, thrown_ptr,
handler_switch_value, language_specific_data,
landing_pad, action_record);
}
return _URC_HANDLER_FOUND;
}
install_context:
// We can't use any of the cxa routines with foreign exceptions,
// because they all expect ue_header to be a struct __cxa_exception.
// So in that case, call terminate or unexpected directly.
if ((actions & _UA_FORCE_UNWIND)
|| foreign_exception)
{
if (found_type == found_terminate)
std::terminate ();
else if (handler_switch_value < 0)
{
__try
{ std::unexpected (); }
__catch(...)
{ std::terminate (); }
}
}
else
{
if (found_type == found_terminate)
__cxa_call_terminate(ue_header);
// Cache the TType base value for __cxa_call_unexpected, as we won't
// have an _Unwind_Context then.
if (handler_switch_value < 0)
{
parse_lsda_header (context, language_specific_data, &info);
info.ttype_base = base_of_encoded_value (info.ttype_encoding,
context);
#ifdef __ARM_EABI_UNWINDER__
const _Unwind_Word* e;
_Unwind_Word n;
e = ((const _Unwind_Word*) info.TType) - handler_switch_value - 1;
// Count the number of rtti objects.
n = 0;
while (e[n] != 0)
n++;
// Count.
ue_header->barrier_cache.bitpattern[1] = n;
// Base
ue_header->barrier_cache.bitpattern[2] = info.ttype_base;
// Stride.
ue_header->barrier_cache.bitpattern[3] = 4;
// List head.
ue_header->barrier_cache.bitpattern[4] = (_Unwind_Word) e;
#else
xh->catchTemp = base_of_encoded_value (info.ttype_encoding, context);
#endif
}
}
/* For targets with pointers smaller than the word size, we must extend the
pointer, and this extension is target dependent. */
_Unwind_SetGR (context, __builtin_eh_return_data_regno (0),
__builtin_extend_pointer (ue_header));
_Unwind_SetGR (context, __builtin_eh_return_data_regno (1),
handler_switch_value);
_Unwind_SetIP (context, landing_pad);
#ifdef __ARM_EABI_UNWINDER__
if (found_type == found_cleanup)
__cxa_begin_cleanup(ue_header);
#endif
return _URC_INSTALL_CONTEXT;
}
/* The ARM EABI implementation of __cxa_call_unexpected is in a
different file so that the personality routine (PR) can be used
standalone. The generic routine shared datastructures with the PR
so it is most convenient to implement it here. */
#ifndef __ARM_EABI_UNWINDER__
extern "C" void
__cxa_call_unexpected (void *exc_obj_in)
{
_Unwind_Exception *exc_obj
= reinterpret_cast <_Unwind_Exception *>(exc_obj_in);
__cxa_begin_catch (exc_obj);
// This function is a handler for our exception argument. If we exit
// by throwing a different exception, we'll need the original cleaned up.
struct end_catch_protect
{
end_catch_protect() { }
~end_catch_protect() { __cxa_end_catch(); }
} end_catch_protect_obj;
lsda_header_info info;
__cxa_exception *xh = __get_exception_header_from_ue (exc_obj);
const unsigned char *xh_lsda;
_Unwind_Sword xh_switch_value;
std::terminate_handler xh_terminate_handler;
// If the unexpectedHandler rethrows the exception (e.g. to categorize it),
// it will clobber data about the current handler. So copy the data out now.
xh_lsda = xh->languageSpecificData;
xh_switch_value = xh->handlerSwitchValue;
xh_terminate_handler = xh->terminateHandler;
info.ttype_base = (_Unwind_Ptr) xh->catchTemp;
__try
{ __unexpected (xh->unexpectedHandler); }
__catch(...)
{
// Get the exception thrown from unexpected.
__cxa_eh_globals *globals = __cxa_get_globals_fast ();
__cxa_exception *new_xh = globals->caughtExceptions;
void *new_ptr = __get_object_from_ambiguous_exception (new_xh);
// We don't quite have enough stuff cached; re-parse the LSDA.
parse_lsda_header (0, xh_lsda, &info);
// If this new exception meets the exception spec, allow it.
if (check_exception_spec (&info, __get_exception_header_from_obj
(new_ptr)->exceptionType,
new_ptr, xh_switch_value))
{ __throw_exception_again; }
// If the exception spec allows std::bad_exception, throw that.
// We don't have a thrown object to compare against, but since
// bad_exception doesn't have virtual bases, that's OK; just pass 0.
#if __cpp_exceptions && __cpp_rtti
const std::type_info &bad_exc = typeid (std::bad_exception);
if (check_exception_spec (&info, &bad_exc, 0, xh_switch_value))
throw std::bad_exception();
#endif
// Otherwise, die.
__terminate (xh_terminate_handler);
}
}
#endif
#if defined (__SEH__) && !defined (__USING_SJLJ_EXCEPTIONS__)
extern "C"
EXCEPTION_DISPOSITION
__gxx_personality_seh0 (PEXCEPTION_RECORD ms_exc, void *this_frame,
PCONTEXT ms_orig_context, PDISPATCHER_CONTEXT ms_disp)
{
return _GCC_specific_handler (ms_exc, this_frame, ms_orig_context,
ms_disp, __gxx_personality_imp);
}
#endif /* SEH */
} // namespace __cxxabiv1
|