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			804 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			804 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C++
		
	
	
	
| // -*- C++ -*- The GNU C++ exception personality routine.
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| // Copyright (C) 2001-2016 Free Software Foundation, Inc.
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| //
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| // This file is part of GCC.
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| //
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| // GCC is free software; you can redistribute it and/or modify
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| // it under the terms of the GNU General Public License as published by
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| // the Free Software Foundation; either version 3, or (at your option)
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| // any later version.
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| //
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| // GCC is distributed in the hope that it will be useful,
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| // but WITHOUT ANY WARRANTY; without even the implied warranty of
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| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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| // GNU General Public License for more details.
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| //
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| // Under Section 7 of GPL version 3, you are granted additional
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| // permissions described in the GCC Runtime Library Exception, version
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| // 3.1, as published by the Free Software Foundation.
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| 
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| // You should have received a copy of the GNU General Public License and
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| // a copy of the GCC Runtime Library Exception along with this program;
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| // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
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| // <http://www.gnu.org/licenses/>.
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| 
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| #include <bits/c++config.h>
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| #include <cstdlib>
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| #include <bits/exception_defines.h>
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| #include <cxxabi.h>
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| #include "unwind-cxx.h"
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| 
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| 
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| using namespace __cxxabiv1;
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| 
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| #include "unwind-pe.h"
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| 
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| 
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| struct lsda_header_info
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| {
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|   _Unwind_Ptr Start;
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|   _Unwind_Ptr LPStart;
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|   _Unwind_Ptr ttype_base;
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|   const unsigned char *TType;
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|   const unsigned char *action_table;
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|   unsigned char ttype_encoding;
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|   unsigned char call_site_encoding;
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| };
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| 
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| static const unsigned char *
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| parse_lsda_header (_Unwind_Context *context, const unsigned char *p,
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| 		   lsda_header_info *info)
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| {
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|   _uleb128_t tmp;
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|   unsigned char lpstart_encoding;
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| 
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|   info->Start = (context ? _Unwind_GetRegionStart (context) : 0);
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| 
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|   // Find @LPStart, the base to which landing pad offsets are relative.
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|   lpstart_encoding = *p++;
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|   if (lpstart_encoding != DW_EH_PE_omit)
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|     p = read_encoded_value (context, lpstart_encoding, p, &info->LPStart);
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|   else
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|     info->LPStart = info->Start;
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| 
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|   // Find @TType, the base of the handler and exception spec type data.
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|   info->ttype_encoding = *p++;
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|   if (info->ttype_encoding != DW_EH_PE_omit)
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|     {
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| #if _GLIBCXX_OVERRIDE_TTYPE_ENCODING
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|       /* Older ARM EABI toolchains set this value incorrectly, so use a
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| 	 hardcoded OS-specific format.  */
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|       info->ttype_encoding = _GLIBCXX_OVERRIDE_TTYPE_ENCODING;
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| #endif
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|       p = read_uleb128 (p, &tmp);
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|       info->TType = p + tmp;
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|     }
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|   else
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|     info->TType = 0;
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| 
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|   // The encoding and length of the call-site table; the action table
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|   // immediately follows.
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|   info->call_site_encoding = *p++;
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|   p = read_uleb128 (p, &tmp);
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|   info->action_table = p + tmp;
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| 
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|   return p;
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| }
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| 
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| // Return an element from a type table.
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| 
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| static const std::type_info *
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| get_ttype_entry (lsda_header_info *info, _uleb128_t i)
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| {
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|   _Unwind_Ptr ptr;
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| 
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|   i *= size_of_encoded_value (info->ttype_encoding);
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|   read_encoded_value_with_base (info->ttype_encoding, info->ttype_base,
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| 				info->TType - i, &ptr);
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| 
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|   return reinterpret_cast<const std::type_info *>(ptr);
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| }
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| 
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| #ifdef __ARM_EABI_UNWINDER__
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| 
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| // The ABI provides a routine for matching exception object types.
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| typedef _Unwind_Control_Block _throw_typet;
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| #define get_adjusted_ptr(catch_type, throw_type, thrown_ptr_p) \
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|   (__cxa_type_match (throw_type, catch_type, false, thrown_ptr_p) \
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|    != ctm_failed)
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| 
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| // Return true if THROW_TYPE matches one if the filter types.
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| 
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| static bool
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| check_exception_spec(lsda_header_info* info, _throw_typet* throw_type,
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| 		     void* thrown_ptr, _sleb128_t filter_value)
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| {
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|   const _uleb128_t* e = ((const _uleb128_t*) info->TType)
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| 			  - filter_value - 1;
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| 
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|   while (1)
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|     {
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|       const std::type_info* catch_type;
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|       _uleb128_t tmp;
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| 
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|       tmp = *e;
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|       
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|       // Zero signals the end of the list.  If we've not found
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|       // a match by now, then we've failed the specification.
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|       if (tmp == 0)
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|         return false;
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| 
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|       tmp = _Unwind_decode_typeinfo_ptr(info->ttype_base, (_Unwind_Word) e);
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| 
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|       // Match a ttype entry.
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|       catch_type = reinterpret_cast<const std::type_info*>(tmp);
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| 
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|       // ??? There is currently no way to ask the RTTI code about the
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|       // relationship between two types without reference to a specific
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|       // object.  There should be; then we wouldn't need to mess with
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|       // thrown_ptr here.
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|       if (get_adjusted_ptr(catch_type, throw_type, &thrown_ptr))
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| 	return true;
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| 
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|       // Advance to the next entry.
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|       e++;
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|     }
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| }
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| 
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| 
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| // Save stage1 handler information in the exception object
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| 
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| static inline void
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| save_caught_exception(struct _Unwind_Exception* ue_header,
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| 		      struct _Unwind_Context* context,
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| 		      void* thrown_ptr,
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| 		      int handler_switch_value,
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| 		      const unsigned char* language_specific_data,
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| 		      _Unwind_Ptr landing_pad,
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| 		      const unsigned char* action_record
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| 			__attribute__((__unused__)))
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| {
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|     ue_header->barrier_cache.sp = _Unwind_GetGR(context, UNWIND_STACK_REG);
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|     ue_header->barrier_cache.bitpattern[0] = (_uw) thrown_ptr;
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|     ue_header->barrier_cache.bitpattern[1]
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|       = (_uw) handler_switch_value;
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|     ue_header->barrier_cache.bitpattern[2]
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|       = (_uw) language_specific_data;
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|     ue_header->barrier_cache.bitpattern[3] = (_uw) landing_pad;
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| }
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| 
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| 
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| // Restore the catch handler data saved during phase1.
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| 
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| static inline void
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| restore_caught_exception(struct _Unwind_Exception* ue_header,
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| 			 int& handler_switch_value,
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| 			 const unsigned char*& language_specific_data,
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| 			 _Unwind_Ptr& landing_pad)
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| {
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|   handler_switch_value = (int) ue_header->barrier_cache.bitpattern[1];
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|   language_specific_data =
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|     (const unsigned char*) ue_header->barrier_cache.bitpattern[2];
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|   landing_pad = (_Unwind_Ptr) ue_header->barrier_cache.bitpattern[3];
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| }
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| 
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| #define CONTINUE_UNWINDING \
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|   do								\
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|     {								\
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|       if (__gnu_unwind_frame(ue_header, context) != _URC_OK)	\
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| 	return _URC_FAILURE;					\
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|       return _URC_CONTINUE_UNWIND;				\
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|     }								\
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|   while (0)
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| 
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| // Return true if the filter spec is empty, ie throw().
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| 
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| static bool
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| empty_exception_spec (lsda_header_info *info, _Unwind_Sword filter_value)
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| {
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|   const _Unwind_Word* e = ((const _Unwind_Word*) info->TType)
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| 			  - filter_value - 1;
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| 
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|   return *e == 0;
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| }
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| 
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| #else
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| typedef const std::type_info _throw_typet;
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| 
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| 
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| // Given the thrown type THROW_TYPE, pointer to a variable containing a
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| // pointer to the exception object THROWN_PTR_P and a type CATCH_TYPE to
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| // compare against, return whether or not there is a match and if so,
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| // update *THROWN_PTR_P.
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| 
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| static bool
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| get_adjusted_ptr (const std::type_info *catch_type,
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| 		  const std::type_info *throw_type,
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| 		  void **thrown_ptr_p)
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| {
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|   void *thrown_ptr = *thrown_ptr_p;
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| 
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|   // Pointer types need to adjust the actual pointer, not
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|   // the pointer to pointer that is the exception object.
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|   // This also has the effect of passing pointer types
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|   // "by value" through the __cxa_begin_catch return value.
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|   if (throw_type->__is_pointer_p ())
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|     thrown_ptr = *(void **) thrown_ptr;
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| 
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|   if (catch_type->__do_catch (throw_type, &thrown_ptr, 1))
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|     {
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|       *thrown_ptr_p = thrown_ptr;
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|       return true;
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|     }
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| 
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|   return false;
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| }
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| 
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| // Return true if THROW_TYPE matches one if the filter types.
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| 
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| static bool
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| check_exception_spec(lsda_header_info* info, _throw_typet* throw_type,
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| 		      void* thrown_ptr, _sleb128_t filter_value)
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| {
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|   const unsigned char *e = info->TType - filter_value - 1;
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| 
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|   while (1)
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|     {
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|       const std::type_info *catch_type;
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|       _uleb128_t tmp;
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| 
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|       e = read_uleb128 (e, &tmp);
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| 
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|       // Zero signals the end of the list.  If we've not found
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|       // a match by now, then we've failed the specification.
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|       if (tmp == 0)
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|         return false;
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| 
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|       // Match a ttype entry.
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|       catch_type = get_ttype_entry (info, tmp);
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| 
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|       // ??? There is currently no way to ask the RTTI code about the
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|       // relationship between two types without reference to a specific
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|       // object.  There should be; then we wouldn't need to mess with
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|       // thrown_ptr here.
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|       if (get_adjusted_ptr (catch_type, throw_type, &thrown_ptr))
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| 	return true;
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|     }
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| }
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| 
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| 
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| // Save stage1 handler information in the exception object
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| 
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| static inline void
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| save_caught_exception(struct _Unwind_Exception* ue_header,
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| 		      struct _Unwind_Context* context
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| 			__attribute__((__unused__)),
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| 		      void* thrown_ptr,
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| 		      int handler_switch_value,
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| 		      const unsigned char* language_specific_data,
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| 		      _Unwind_Ptr landing_pad __attribute__((__unused__)),
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| 		      const unsigned char* action_record)
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| {
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|   __cxa_exception* xh = __get_exception_header_from_ue(ue_header);
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| 
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|   xh->handlerSwitchValue = handler_switch_value;
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|   xh->actionRecord = action_record;
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|   xh->languageSpecificData = language_specific_data;
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|   xh->adjustedPtr = thrown_ptr;
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| 
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|   // ??? Completely unknown what this field is supposed to be for.
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|   // ??? Need to cache TType encoding base for call_unexpected.
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|   xh->catchTemp = landing_pad;
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| }
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| 
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| 
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| // Restore the catch handler information saved during phase1.
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| 
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| static inline void
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| restore_caught_exception(struct _Unwind_Exception* ue_header,
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| 			 int& handler_switch_value,
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| 			 const unsigned char*& language_specific_data,
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| 			 _Unwind_Ptr& landing_pad)
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| {
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|   __cxa_exception* xh = __get_exception_header_from_ue(ue_header);
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|   handler_switch_value = xh->handlerSwitchValue;
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|   language_specific_data = xh->languageSpecificData;
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|   landing_pad = (_Unwind_Ptr) xh->catchTemp;
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| }
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| 
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| #define CONTINUE_UNWINDING return _URC_CONTINUE_UNWIND
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| 
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| // Return true if the filter spec is empty, ie throw().
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| 
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| static bool
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| empty_exception_spec (lsda_header_info *info, _Unwind_Sword filter_value)
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| {
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|   const unsigned char *e = info->TType - filter_value - 1;
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|   _uleb128_t tmp;
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| 
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|   e = read_uleb128 (e, &tmp);
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|   return tmp == 0;
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| }
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| 
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| #endif // !__ARM_EABI_UNWINDER__
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| 
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| namespace __cxxabiv1
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| {
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| 
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| // Using a different personality function name causes link failures
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| // when trying to mix code using different exception handling models.
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| #ifdef __USING_SJLJ_EXCEPTIONS__
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| #define PERSONALITY_FUNCTION	__gxx_personality_sj0
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| #define __builtin_eh_return_data_regno(x) x
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| #elif defined(__SEH__)
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| #define PERSONALITY_FUNCTION	__gxx_personality_imp
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| #else
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| #define PERSONALITY_FUNCTION	__gxx_personality_v0
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| #endif
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| 
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| #if defined (__SEH__) && !defined (__USING_SJLJ_EXCEPTIONS__)
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| static
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| #else
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| extern "C"
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| #endif
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| _Unwind_Reason_Code
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| #ifdef __ARM_EABI_UNWINDER__
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| PERSONALITY_FUNCTION (_Unwind_State state,
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| 		      struct _Unwind_Exception* ue_header,
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| 		      struct _Unwind_Context* context)
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| #else
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| PERSONALITY_FUNCTION (int version,
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| 		      _Unwind_Action actions,
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| 		      _Unwind_Exception_Class exception_class,
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| 		      struct _Unwind_Exception *ue_header,
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| 		      struct _Unwind_Context *context)
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| #endif
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| {
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|   enum found_handler_type
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|   {
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|     found_nothing,
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|     found_terminate,
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|     found_cleanup,
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|     found_handler
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|   } found_type;
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| 
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|   lsda_header_info info;
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|   const unsigned char *language_specific_data;
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|   const unsigned char *action_record;
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|   const unsigned char *p;
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|   _Unwind_Ptr landing_pad, ip;
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|   int handler_switch_value;
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|   void* thrown_ptr = 0;
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|   bool foreign_exception;
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|   int ip_before_insn = 0;
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| 
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| #ifdef __ARM_EABI_UNWINDER__
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|   _Unwind_Action actions;
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| 
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|   switch (state & _US_ACTION_MASK)
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|     {
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|     case _US_VIRTUAL_UNWIND_FRAME:
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|       // If the unwind state pattern is
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|       // _US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND
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|       // then we don't need to search for any handler as it is not a real
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|       // exception. Just unwind the stack.
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|       if (state & _US_FORCE_UNWIND)
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| 	CONTINUE_UNWINDING;
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|       actions = _UA_SEARCH_PHASE;
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|       break;
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| 
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|     case _US_UNWIND_FRAME_STARTING:
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|       actions = _UA_CLEANUP_PHASE;
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|       if (!(state & _US_FORCE_UNWIND)
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| 	  && ue_header->barrier_cache.sp == _Unwind_GetGR(context,
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| 							  UNWIND_STACK_REG))
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| 	actions |= _UA_HANDLER_FRAME;
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|       break;
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| 
 | ||
|     case _US_UNWIND_FRAME_RESUME:
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|       CONTINUE_UNWINDING;
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|       break;
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| 
 | ||
|     default:
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|       std::abort();
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|     }
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|   actions |= state & _US_FORCE_UNWIND;
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| 
 | ||
|   // We don't know which runtime we're working with, so can't check this.
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|   // However the ABI routines hide this from us, and we don't actually need
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|   // to know.
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|   foreign_exception = false;
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| 
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|   // The dwarf unwinder assumes the context structure holds things like the
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|   // function and LSDA pointers.  The ARM implementation caches these in
 | ||
|   // the exception header (UCB).  To avoid rewriting everything we make a
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|   // virtual scratch register point at the UCB.
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|   ip = (_Unwind_Ptr) ue_header;
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|   _Unwind_SetGR(context, UNWIND_POINTER_REG, ip);
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| #else
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|   __cxa_exception* xh = __get_exception_header_from_ue(ue_header);
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| 
 | ||
|   // Interface version check.
 | ||
|   if (version != 1)
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|     return _URC_FATAL_PHASE1_ERROR;
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|   foreign_exception = !__is_gxx_exception_class(exception_class);
 | ||
| #endif
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| 
 | ||
|   // Shortcut for phase 2 found handler for domestic exception.
 | ||
|   if (actions == (_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME)
 | ||
|       && !foreign_exception)
 | ||
|     {
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|       restore_caught_exception(ue_header, handler_switch_value,
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| 			       language_specific_data, landing_pad);
 | ||
|       found_type = (landing_pad == 0 ? found_terminate : found_handler);
 | ||
|       goto install_context;
 | ||
|     }
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| 
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|   language_specific_data = (const unsigned char *)
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|     _Unwind_GetLanguageSpecificData (context);
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| 
 | ||
|   // If no LSDA, then there are no handlers or cleanups.
 | ||
|   if (! language_specific_data)
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|     CONTINUE_UNWINDING;
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| 
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|   // Parse the LSDA header.
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|   p = parse_lsda_header (context, language_specific_data, &info);
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|   info.ttype_base = base_of_encoded_value (info.ttype_encoding, context);
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| #ifdef _GLIBCXX_HAVE_GETIPINFO
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|   ip = _Unwind_GetIPInfo (context, &ip_before_insn);
 | ||
| #else
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|   ip = _Unwind_GetIP (context);
 | ||
| #endif
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|   if (! ip_before_insn)
 | ||
|     --ip;
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|   landing_pad = 0;
 | ||
|   action_record = 0;
 | ||
|   handler_switch_value = 0;
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| 
 | ||
| #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)
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|     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);
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| 	  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
 |