Avoid tr '\n', for Solaris /usr/bin/tr.
[gcc.git] / libstdc++-v3 / libsupc++ / eh_personality.cc
1 // -*- C++ -*- The GNU C++ exception personality routine.
2 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
3 // Free Software Foundation, Inc.
4 //
5 // This file is part of GCC.
6 //
7 // GCC is free software; you can redistribute it and/or modify
8 // it under the terms of the GNU General Public License as published by
9 // the Free Software Foundation; either version 3, or (at your option)
10 // any later version.
11 //
12 // GCC is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16 //
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
20
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
25
26 #include <bits/c++config.h>
27 #include <cstdlib>
28 #include <exception_defines.h>
29 #include <cxxabi.h>
30 #include "unwind-cxx.h"
31
32 using namespace __cxxabiv1;
33
34 #ifdef __ARM_EABI_UNWINDER__
35 #define NO_SIZE_OF_ENCODED_VALUE
36 #endif
37
38 #include "unwind-pe.h"
39
40 \f
41 struct lsda_header_info
42 {
43 _Unwind_Ptr Start;
44 _Unwind_Ptr LPStart;
45 _Unwind_Ptr ttype_base;
46 const unsigned char *TType;
47 const unsigned char *action_table;
48 unsigned char ttype_encoding;
49 unsigned char call_site_encoding;
50 };
51
52 static const unsigned char *
53 parse_lsda_header (_Unwind_Context *context, const unsigned char *p,
54 lsda_header_info *info)
55 {
56 _uleb128_t tmp;
57 unsigned char lpstart_encoding;
58
59 info->Start = (context ? _Unwind_GetRegionStart (context) : 0);
60
61 // Find @LPStart, the base to which landing pad offsets are relative.
62 lpstart_encoding = *p++;
63 if (lpstart_encoding != DW_EH_PE_omit)
64 p = read_encoded_value (context, lpstart_encoding, p, &info->LPStart);
65 else
66 info->LPStart = info->Start;
67
68 // Find @TType, the base of the handler and exception spec type data.
69 info->ttype_encoding = *p++;
70 if (info->ttype_encoding != DW_EH_PE_omit)
71 {
72 p = read_uleb128 (p, &tmp);
73 info->TType = p + tmp;
74 }
75 else
76 info->TType = 0;
77
78 // The encoding and length of the call-site table; the action table
79 // immediately follows.
80 info->call_site_encoding = *p++;
81 p = read_uleb128 (p, &tmp);
82 info->action_table = p + tmp;
83
84 return p;
85 }
86
87 #ifdef __ARM_EABI_UNWINDER__
88
89 // Return an element from a type table.
90
91 static const std::type_info*
92 get_ttype_entry(lsda_header_info* info, _uleb128_t i)
93 {
94 _Unwind_Ptr ptr;
95
96 ptr = (_Unwind_Ptr) (info->TType - (i * 4));
97 ptr = _Unwind_decode_target2(ptr);
98
99 return reinterpret_cast<const std::type_info *>(ptr);
100 }
101
102 // The ABI provides a routine for matching exception object types.
103 typedef _Unwind_Control_Block _throw_typet;
104 #define get_adjusted_ptr(catch_type, throw_type, thrown_ptr_p) \
105 (__cxa_type_match (throw_type, catch_type, false, thrown_ptr_p) \
106 != ctm_failed)
107
108 // Return true if THROW_TYPE matches one if the filter types.
109
110 static bool
111 check_exception_spec(lsda_header_info* info, _throw_typet* throw_type,
112 void* thrown_ptr, _sleb128_t filter_value)
113 {
114 const _uleb128_t* e = ((const _uleb128_t*) info->TType)
115 - filter_value - 1;
116
117 while (1)
118 {
119 const std::type_info* catch_type;
120 _uleb128_t tmp;
121
122 tmp = *e;
123
124 // Zero signals the end of the list. If we've not found
125 // a match by now, then we've failed the specification.
126 if (tmp == 0)
127 return false;
128
129 tmp = _Unwind_decode_target2((_Unwind_Word) e);
130
131 // Match a ttype entry.
132 catch_type = reinterpret_cast<const std::type_info*>(tmp);
133
134 // ??? There is currently no way to ask the RTTI code about the
135 // relationship between two types without reference to a specific
136 // object. There should be; then we wouldn't need to mess with
137 // thrown_ptr here.
138 if (get_adjusted_ptr(catch_type, throw_type, &thrown_ptr))
139 return true;
140
141 // Advance to the next entry.
142 e++;
143 }
144 }
145
146
147 // Save stage1 handler information in the exception object
148
149 static inline void
150 save_caught_exception(struct _Unwind_Exception* ue_header,
151 struct _Unwind_Context* context,
152 void* thrown_ptr,
153 int handler_switch_value,
154 const unsigned char* language_specific_data,
155 _Unwind_Ptr landing_pad,
156 const unsigned char* action_record
157 __attribute__((__unused__)))
158 {
159 ue_header->barrier_cache.sp = _Unwind_GetGR(context, 13);
160 ue_header->barrier_cache.bitpattern[0] = (_uw) thrown_ptr;
161 ue_header->barrier_cache.bitpattern[1]
162 = (_uw) handler_switch_value;
163 ue_header->barrier_cache.bitpattern[2]
164 = (_uw) language_specific_data;
165 ue_header->barrier_cache.bitpattern[3] = (_uw) landing_pad;
166 }
167
168
169 // Restore the catch handler data saved during phase1.
170
171 static inline void
172 restore_caught_exception(struct _Unwind_Exception* ue_header,
173 int& handler_switch_value,
174 const unsigned char*& language_specific_data,
175 _Unwind_Ptr& landing_pad)
176 {
177 handler_switch_value = (int) ue_header->barrier_cache.bitpattern[1];
178 language_specific_data =
179 (const unsigned char*) ue_header->barrier_cache.bitpattern[2];
180 landing_pad = (_Unwind_Ptr) ue_header->barrier_cache.bitpattern[3];
181 }
182
183 #define CONTINUE_UNWINDING \
184 do \
185 { \
186 if (__gnu_unwind_frame(ue_header, context) != _URC_OK) \
187 return _URC_FAILURE; \
188 return _URC_CONTINUE_UNWIND; \
189 } \
190 while (0)
191
192 // Return true if the filter spec is empty, ie throw().
193
194 static bool
195 empty_exception_spec (lsda_header_info *info, _Unwind_Sword filter_value)
196 {
197 const _Unwind_Word* e = ((const _Unwind_Word*) info->TType)
198 - filter_value - 1;
199
200 return *e == 0;
201 }
202
203 #else
204 typedef const std::type_info _throw_typet;
205
206
207 // Return an element from a type table.
208
209 static const std::type_info *
210 get_ttype_entry (lsda_header_info *info, _uleb128_t i)
211 {
212 _Unwind_Ptr ptr;
213
214 i *= size_of_encoded_value (info->ttype_encoding);
215 read_encoded_value_with_base (info->ttype_encoding, info->ttype_base,
216 info->TType - i, &ptr);
217
218 return reinterpret_cast<const std::type_info *>(ptr);
219 }
220
221 // Given the thrown type THROW_TYPE, pointer to a variable containing a
222 // pointer to the exception object THROWN_PTR_P and a type CATCH_TYPE to
223 // compare against, return whether or not there is a match and if so,
224 // update *THROWN_PTR_P.
225
226 static bool
227 get_adjusted_ptr (const std::type_info *catch_type,
228 const std::type_info *throw_type,
229 void **thrown_ptr_p)
230 {
231 void *thrown_ptr = *thrown_ptr_p;
232
233 // Pointer types need to adjust the actual pointer, not
234 // the pointer to pointer that is the exception object.
235 // This also has the effect of passing pointer types
236 // "by value" through the __cxa_begin_catch return value.
237 if (throw_type->__is_pointer_p ())
238 thrown_ptr = *(void **) thrown_ptr;
239
240 if (catch_type->__do_catch (throw_type, &thrown_ptr, 1))
241 {
242 *thrown_ptr_p = thrown_ptr;
243 return true;
244 }
245
246 return false;
247 }
248
249 // Return true if THROW_TYPE matches one if the filter types.
250
251 static bool
252 check_exception_spec(lsda_header_info* info, _throw_typet* throw_type,
253 void* thrown_ptr, _sleb128_t filter_value)
254 {
255 const unsigned char *e = info->TType - filter_value - 1;
256
257 while (1)
258 {
259 const std::type_info *catch_type;
260 _uleb128_t tmp;
261
262 e = read_uleb128 (e, &tmp);
263
264 // Zero signals the end of the list. If we've not found
265 // a match by now, then we've failed the specification.
266 if (tmp == 0)
267 return false;
268
269 // Match a ttype entry.
270 catch_type = get_ttype_entry (info, tmp);
271
272 // ??? There is currently no way to ask the RTTI code about the
273 // relationship between two types without reference to a specific
274 // object. There should be; then we wouldn't need to mess with
275 // thrown_ptr here.
276 if (get_adjusted_ptr (catch_type, throw_type, &thrown_ptr))
277 return true;
278 }
279 }
280
281
282 // Save stage1 handler information in the exception object
283
284 static inline void
285 save_caught_exception(struct _Unwind_Exception* ue_header,
286 struct _Unwind_Context* context
287 __attribute__((__unused__)),
288 void* thrown_ptr,
289 int handler_switch_value,
290 const unsigned char* language_specific_data,
291 _Unwind_Ptr landing_pad __attribute__((__unused__)),
292 const unsigned char* action_record)
293 {
294 __cxa_exception* xh = __get_exception_header_from_ue(ue_header);
295
296 xh->handlerSwitchValue = handler_switch_value;
297 xh->actionRecord = action_record;
298 xh->languageSpecificData = language_specific_data;
299 xh->adjustedPtr = thrown_ptr;
300
301 // ??? Completely unknown what this field is supposed to be for.
302 // ??? Need to cache TType encoding base for call_unexpected.
303 xh->catchTemp = landing_pad;
304 }
305
306
307 // Restore the catch handler information saved during phase1.
308
309 static inline void
310 restore_caught_exception(struct _Unwind_Exception* ue_header,
311 int& handler_switch_value,
312 const unsigned char*& language_specific_data,
313 _Unwind_Ptr& landing_pad)
314 {
315 __cxa_exception* xh = __get_exception_header_from_ue(ue_header);
316 handler_switch_value = xh->handlerSwitchValue;
317 language_specific_data = xh->languageSpecificData;
318 landing_pad = (_Unwind_Ptr) xh->catchTemp;
319 }
320
321 #define CONTINUE_UNWINDING return _URC_CONTINUE_UNWIND
322
323 // Return true if the filter spec is empty, ie throw().
324
325 static bool
326 empty_exception_spec (lsda_header_info *info, _Unwind_Sword filter_value)
327 {
328 const unsigned char *e = info->TType - filter_value - 1;
329 _uleb128_t tmp;
330
331 e = read_uleb128 (e, &tmp);
332 return tmp == 0;
333 }
334
335 #endif // !__ARM_EABI_UNWINDER__
336
337 namespace __cxxabiv1
338 {
339
340 // Using a different personality function name causes link failures
341 // when trying to mix code using different exception handling models.
342 #ifdef _GLIBCXX_SJLJ_EXCEPTIONS
343 #define PERSONALITY_FUNCTION __gxx_personality_sj0
344 #define __builtin_eh_return_data_regno(x) x
345 #else
346 #define PERSONALITY_FUNCTION __gxx_personality_v0
347 #endif
348
349 extern "C" _Unwind_Reason_Code
350 #ifdef __ARM_EABI_UNWINDER__
351 PERSONALITY_FUNCTION (_Unwind_State state,
352 struct _Unwind_Exception* ue_header,
353 struct _Unwind_Context* context)
354 #else
355 PERSONALITY_FUNCTION (int version,
356 _Unwind_Action actions,
357 _Unwind_Exception_Class exception_class,
358 struct _Unwind_Exception *ue_header,
359 struct _Unwind_Context *context)
360 #endif
361 {
362 enum found_handler_type
363 {
364 found_nothing,
365 found_terminate,
366 found_cleanup,
367 found_handler
368 } found_type;
369
370 lsda_header_info info;
371 const unsigned char *language_specific_data;
372 const unsigned char *action_record;
373 const unsigned char *p;
374 _Unwind_Ptr landing_pad, ip;
375 int handler_switch_value;
376 void* thrown_ptr = 0;
377 bool foreign_exception;
378 int ip_before_insn = 0;
379
380 #ifdef __ARM_EABI_UNWINDER__
381 _Unwind_Action actions;
382
383 switch (state & _US_ACTION_MASK)
384 {
385 case _US_VIRTUAL_UNWIND_FRAME:
386 actions = _UA_SEARCH_PHASE;
387 break;
388
389 case _US_UNWIND_FRAME_STARTING:
390 actions = _UA_CLEANUP_PHASE;
391 if (!(state & _US_FORCE_UNWIND)
392 && ue_header->barrier_cache.sp == _Unwind_GetGR(context, 13))
393 actions |= _UA_HANDLER_FRAME;
394 break;
395
396 case _US_UNWIND_FRAME_RESUME:
397 CONTINUE_UNWINDING;
398 break;
399
400 default:
401 std::abort();
402 }
403 actions |= state & _US_FORCE_UNWIND;
404
405 // We don't know which runtime we're working with, so can't check this.
406 // However the ABI routines hide this from us, and we don't actually need
407 // to know.
408 foreign_exception = false;
409
410 // The dwarf unwinder assumes the context structure holds things like the
411 // function and LSDA pointers. The ARM implementation caches these in
412 // the exception header (UCB). To avoid rewriting everything we make the
413 // virtual IP register point at the UCB.
414 ip = (_Unwind_Ptr) ue_header;
415 _Unwind_SetGR(context, 12, ip);
416 #else
417 __cxa_exception* xh = __get_exception_header_from_ue(ue_header);
418
419 // Interface version check.
420 if (version != 1)
421 return _URC_FATAL_PHASE1_ERROR;
422 foreign_exception = !__is_gxx_exception_class(exception_class);
423 #endif
424
425 // Shortcut for phase 2 found handler for domestic exception.
426 if (actions == (_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME)
427 && !foreign_exception)
428 {
429 restore_caught_exception(ue_header, handler_switch_value,
430 language_specific_data, landing_pad);
431 found_type = (landing_pad == 0 ? found_terminate : found_handler);
432 goto install_context;
433 }
434
435 language_specific_data = (const unsigned char *)
436 _Unwind_GetLanguageSpecificData (context);
437
438 // If no LSDA, then there are no handlers or cleanups.
439 if (! language_specific_data)
440 CONTINUE_UNWINDING;
441
442 // Parse the LSDA header.
443 p = parse_lsda_header (context, language_specific_data, &info);
444 info.ttype_base = base_of_encoded_value (info.ttype_encoding, context);
445 #ifdef _GLIBCXX_HAVE_GETIPINFO
446 ip = _Unwind_GetIPInfo (context, &ip_before_insn);
447 #else
448 ip = _Unwind_GetIP (context);
449 #endif
450 if (! ip_before_insn)
451 --ip;
452 landing_pad = 0;
453 action_record = 0;
454 handler_switch_value = 0;
455
456 #ifdef _GLIBCXX_SJLJ_EXCEPTIONS
457 // The given "IP" is an index into the call-site table, with two
458 // exceptions -- -1 means no-action, and 0 means terminate. But
459 // since we're using uleb128 values, we've not got random access
460 // to the array.
461 if ((int) ip < 0)
462 return _URC_CONTINUE_UNWIND;
463 else if (ip == 0)
464 {
465 // Fall through to set found_terminate.
466 }
467 else
468 {
469 _uleb128_t cs_lp, cs_action;
470 do
471 {
472 p = read_uleb128 (p, &cs_lp);
473 p = read_uleb128 (p, &cs_action);
474 }
475 while (--ip);
476
477 // Can never have null landing pad for sjlj -- that would have
478 // been indicated by a -1 call site index.
479 landing_pad = cs_lp + 1;
480 if (cs_action)
481 action_record = info.action_table + cs_action - 1;
482 goto found_something;
483 }
484 #else
485 // Search the call-site table for the action associated with this IP.
486 while (p < info.action_table)
487 {
488 _Unwind_Ptr cs_start, cs_len, cs_lp;
489 _uleb128_t cs_action;
490
491 // Note that all call-site encodings are "absolute" displacements.
492 p = read_encoded_value (0, info.call_site_encoding, p, &cs_start);
493 p = read_encoded_value (0, info.call_site_encoding, p, &cs_len);
494 p = read_encoded_value (0, info.call_site_encoding, p, &cs_lp);
495 p = read_uleb128 (p, &cs_action);
496
497 // The table is sorted, so if we've passed the ip, stop.
498 if (ip < info.Start + cs_start)
499 p = info.action_table;
500 else if (ip < info.Start + cs_start + cs_len)
501 {
502 if (cs_lp)
503 landing_pad = info.LPStart + cs_lp;
504 if (cs_action)
505 action_record = info.action_table + cs_action - 1;
506 goto found_something;
507 }
508 }
509 #endif // _GLIBCXX_SJLJ_EXCEPTIONS
510
511 // If ip is not present in the table, call terminate. This is for
512 // a destructor inside a cleanup, or a library routine the compiler
513 // was not expecting to throw.
514 found_type = found_terminate;
515 goto do_something;
516
517 found_something:
518 if (landing_pad == 0)
519 {
520 // If ip is present, and has a null landing pad, there are
521 // no cleanups or handlers to be run.
522 found_type = found_nothing;
523 }
524 else if (action_record == 0)
525 {
526 // If ip is present, has a non-null landing pad, and a null
527 // action table offset, then there are only cleanups present.
528 // Cleanups use a zero switch value, as set above.
529 found_type = found_cleanup;
530 }
531 else
532 {
533 // Otherwise we have a catch handler or exception specification.
534
535 _sleb128_t ar_filter, ar_disp;
536 const std::type_info* catch_type;
537 _throw_typet* throw_type;
538 bool saw_cleanup = false;
539 bool saw_handler = false;
540
541 #ifdef __ARM_EABI_UNWINDER__
542 // ??? How does this work - more importantly, how does it interact with
543 // dependent exceptions?
544 throw_type = ue_header;
545 if (actions & _UA_FORCE_UNWIND)
546 {
547 __GXX_INIT_FORCED_UNWIND_CLASS(ue_header->exception_class);
548 }
549 else if (!foreign_exception)
550 thrown_ptr = __get_object_from_ue (ue_header);
551 #else
552 // During forced unwinding, match a magic exception type.
553 if (actions & _UA_FORCE_UNWIND)
554 {
555 throw_type = &typeid(abi::__forced_unwind);
556 }
557 // With a foreign exception class, there's no exception type.
558 // ??? What to do about GNU Java and GNU Ada exceptions?
559 else if (foreign_exception)
560 {
561 throw_type = &typeid(abi::__foreign_exception);
562 }
563 else
564 {
565 thrown_ptr = __get_object_from_ue (ue_header);
566 throw_type = __get_exception_header_from_obj
567 (thrown_ptr)->exceptionType;
568 }
569 #endif
570
571 while (1)
572 {
573 p = action_record;
574 p = read_sleb128 (p, &ar_filter);
575 read_sleb128 (p, &ar_disp);
576
577 if (ar_filter == 0)
578 {
579 // Zero filter values are cleanups.
580 saw_cleanup = true;
581 }
582 else if (ar_filter > 0)
583 {
584 // Positive filter values are handlers.
585 catch_type = get_ttype_entry (&info, ar_filter);
586
587 // Null catch type is a catch-all handler; we can catch foreign
588 // exceptions with this. Otherwise we must match types.
589 if (! catch_type
590 || (throw_type
591 && get_adjusted_ptr (catch_type, throw_type,
592 &thrown_ptr)))
593 {
594 saw_handler = true;
595 break;
596 }
597 }
598 else
599 {
600 // Negative filter values are exception specifications.
601 // ??? How do foreign exceptions fit in? As far as I can
602 // see we can't match because there's no __cxa_exception
603 // object to stuff bits in for __cxa_call_unexpected to use.
604 // Allow them iff the exception spec is non-empty. I.e.
605 // a throw() specification results in __unexpected.
606 if ((throw_type
607 && !(actions & _UA_FORCE_UNWIND)
608 && !foreign_exception)
609 ? ! check_exception_spec (&info, throw_type, thrown_ptr,
610 ar_filter)
611 : empty_exception_spec (&info, ar_filter))
612 {
613 saw_handler = true;
614 break;
615 }
616 }
617
618 if (ar_disp == 0)
619 break;
620 action_record = p + ar_disp;
621 }
622
623 if (saw_handler)
624 {
625 handler_switch_value = ar_filter;
626 found_type = found_handler;
627 }
628 else
629 found_type = (saw_cleanup ? found_cleanup : found_nothing);
630 }
631
632 do_something:
633 if (found_type == found_nothing)
634 CONTINUE_UNWINDING;
635
636 if (actions & _UA_SEARCH_PHASE)
637 {
638 if (found_type == found_cleanup)
639 CONTINUE_UNWINDING;
640
641 // For domestic exceptions, we cache data from phase 1 for phase 2.
642 if (!foreign_exception)
643 {
644 save_caught_exception(ue_header, context, thrown_ptr,
645 handler_switch_value, language_specific_data,
646 landing_pad, action_record);
647 }
648 return _URC_HANDLER_FOUND;
649 }
650
651 install_context:
652
653 // We can't use any of the cxa routines with foreign exceptions,
654 // because they all expect ue_header to be a struct __cxa_exception.
655 // So in that case, call terminate or unexpected directly.
656 if ((actions & _UA_FORCE_UNWIND)
657 || foreign_exception)
658 {
659 if (found_type == found_terminate)
660 std::terminate ();
661 else if (handler_switch_value < 0)
662 {
663 __try
664 { std::unexpected (); }
665 __catch(...)
666 { std::terminate (); }
667 }
668 }
669 else
670 {
671 if (found_type == found_terminate)
672 __cxa_call_terminate(ue_header);
673
674 // Cache the TType base value for __cxa_call_unexpected, as we won't
675 // have an _Unwind_Context then.
676 if (handler_switch_value < 0)
677 {
678 parse_lsda_header (context, language_specific_data, &info);
679
680 #ifdef __ARM_EABI_UNWINDER__
681 const _Unwind_Word* e;
682 _Unwind_Word n;
683
684 e = ((const _Unwind_Word*) info.TType) - handler_switch_value - 1;
685 // Count the number of rtti objects.
686 n = 0;
687 while (e[n] != 0)
688 n++;
689
690 // Count.
691 ue_header->barrier_cache.bitpattern[1] = n;
692 // Base (obsolete)
693 ue_header->barrier_cache.bitpattern[2] = 0;
694 // Stride.
695 ue_header->barrier_cache.bitpattern[3] = 4;
696 // List head.
697 ue_header->barrier_cache.bitpattern[4] = (_Unwind_Word) e;
698 #else
699 xh->catchTemp = base_of_encoded_value (info.ttype_encoding, context);
700 #endif
701 }
702 }
703
704 /* For targets with pointers smaller than the word size, we must extend the
705 pointer, and this extension is target dependent. */
706 _Unwind_SetGR (context, __builtin_eh_return_data_regno (0),
707 __builtin_extend_pointer (ue_header));
708 _Unwind_SetGR (context, __builtin_eh_return_data_regno (1),
709 handler_switch_value);
710 _Unwind_SetIP (context, landing_pad);
711 #ifdef __ARM_EABI_UNWINDER__
712 if (found_type == found_cleanup)
713 __cxa_begin_cleanup(ue_header);
714 #endif
715 return _URC_INSTALL_CONTEXT;
716 }
717
718 /* The ARM EABI implementation of __cxa_call_unexpected is in a
719 different file so that the personality routine (PR) can be used
720 standalone. The generic routine shared datastructures with the PR
721 so it is most convenient to implement it here. */
722 #ifndef __ARM_EABI_UNWINDER__
723 extern "C" void
724 __cxa_call_unexpected (void *exc_obj_in)
725 {
726 _Unwind_Exception *exc_obj
727 = reinterpret_cast <_Unwind_Exception *>(exc_obj_in);
728
729 __cxa_begin_catch (exc_obj);
730
731 // This function is a handler for our exception argument. If we exit
732 // by throwing a different exception, we'll need the original cleaned up.
733 struct end_catch_protect
734 {
735 end_catch_protect() { }
736 ~end_catch_protect() { __cxa_end_catch(); }
737 } end_catch_protect_obj;
738
739 lsda_header_info info;
740 __cxa_exception *xh = __get_exception_header_from_ue (exc_obj);
741 const unsigned char *xh_lsda;
742 _Unwind_Sword xh_switch_value;
743 std::terminate_handler xh_terminate_handler;
744
745 // If the unexpectedHandler rethrows the exception (e.g. to categorize it),
746 // it will clobber data about the current handler. So copy the data out now.
747 xh_lsda = xh->languageSpecificData;
748 xh_switch_value = xh->handlerSwitchValue;
749 xh_terminate_handler = xh->terminateHandler;
750 info.ttype_base = (_Unwind_Ptr) xh->catchTemp;
751
752 __try
753 { __unexpected (xh->unexpectedHandler); }
754 __catch(...)
755 {
756 // Get the exception thrown from unexpected.
757
758 __cxa_eh_globals *globals = __cxa_get_globals_fast ();
759 __cxa_exception *new_xh = globals->caughtExceptions;
760 void *new_ptr = __get_object_from_ambiguous_exception (new_xh);
761
762 // We don't quite have enough stuff cached; re-parse the LSDA.
763 parse_lsda_header (0, xh_lsda, &info);
764
765 // If this new exception meets the exception spec, allow it.
766 if (check_exception_spec (&info, __get_exception_header_from_obj
767 (new_ptr)->exceptionType,
768 new_ptr, xh_switch_value))
769 __throw_exception_again;
770
771 // If the exception spec allows std::bad_exception, throw that.
772 // We don't have a thrown object to compare against, but since
773 // bad_exception doesn't have virtual bases, that's OK; just pass 0.
774 #ifdef __EXCEPTIONS
775 const std::type_info &bad_exc = typeid (std::bad_exception);
776 if (check_exception_spec (&info, &bad_exc, 0, xh_switch_value))
777 throw std::bad_exception();
778 #endif
779
780 // Otherwise, die.
781 __terminate (xh_terminate_handler);
782 }
783 }
784 #endif
785
786 } // namespace __cxxabiv1