Mercurial > hg > CbC > CbC_llvm
diff libcxxabi/src/cxa_personality.cpp @ 150:1d019706d866
LLVM10
author | anatofuz |
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date | Thu, 13 Feb 2020 15:10:13 +0900 |
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children | 2e18cbf3894f |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/libcxxabi/src/cxa_personality.cpp Thu Feb 13 15:10:13 2020 +0900 @@ -0,0 +1,1324 @@ +//===------------------------- cxa_exception.cpp --------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +// +// This file implements the "Exception Handling APIs" +// https://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html +// http://www.intel.com/design/itanium/downloads/245358.htm +// +//===----------------------------------------------------------------------===// + +#include <assert.h> +#include <stdlib.h> +#include <string.h> +#include <typeinfo> + +#include "__cxxabi_config.h" +#include "cxa_exception.h" +#include "cxa_handlers.h" +#include "private_typeinfo.h" +#include "unwind.h" + +#if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) +#include <windows.h> +#include <winnt.h> + +extern "C" EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD, + void *, PCONTEXT, + PDISPATCHER_CONTEXT, + _Unwind_Personality_Fn); +#endif + +/* + Exception Header Layout: + ++---------------------------+-----------------------------+---------------+ +| __cxa_exception | _Unwind_Exception CLNGC++\0 | thrown object | ++---------------------------+-----------------------------+---------------+ + ^ + | + +-------------------------------------------------------+ + | ++---------------------------+-----------------------------+ +| __cxa_dependent_exception | _Unwind_Exception CLNGC++\1 | ++---------------------------+-----------------------------+ + + Exception Handling Table Layout: + ++-----------------+--------+ +| lpStartEncoding | (char) | ++---------+-------+--------+---------------+-----------------------+ +| lpStart | (encoded with lpStartEncoding) | defaults to funcStart | ++---------+-----+--------+-----------------+---------------+-------+ +| ttypeEncoding | (char) | Encoding of the type_info table | ++---------------+-+------+----+----------------------------+----------------+ +| classInfoOffset | (ULEB128) | Offset to type_info table, defaults to null | ++-----------------++--------+-+----------------------------+----------------+ +| callSiteEncoding | (char) | Encoding for Call Site Table | ++------------------+--+-----+-----+------------------------+--------------------------+ +| callSiteTableLength | (ULEB128) | Call Site Table length, used to find Action table | ++---------------------+-----------+---------------------------------------------------+ +#ifndef __USING_SJLJ_EXCEPTIONS__ ++---------------------+-----------+------------------------------------------------+ +| Beginning of Call Site Table The current ip lies within the | +| ... (start, length) range of one of these | +| call sites. There may be action needed. | +| +-------------+---------------------------------+------------------------------+ | +| | start | (encoded with callSiteEncoding) | offset relative to funcStart | | +| | length | (encoded with callSiteEncoding) | length of code fragment | | +| | landingPad | (encoded with callSiteEncoding) | offset relative to lpStart | | +| | actionEntry | (ULEB128) | Action Table Index 1-based | | +| | | | actionEntry == 0 -> cleanup | | +| +-------------+---------------------------------+------------------------------+ | +| ... | ++----------------------------------------------------------------------------------+ +#else // __USING_SJLJ_EXCEPTIONS__ ++---------------------+-----------+------------------------------------------------+ +| Beginning of Call Site Table The current ip is a 1-based index into | +| ... this table. Or it is -1 meaning no | +| action is needed. Or it is 0 meaning | +| terminate. | +| +-------------+---------------------------------+------------------------------+ | +| | landingPad | (ULEB128) | offset relative to lpStart | | +| | actionEntry | (ULEB128) | Action Table Index 1-based | | +| | | | actionEntry == 0 -> cleanup | | +| +-------------+---------------------------------+------------------------------+ | +| ... | ++----------------------------------------------------------------------------------+ +#endif // __USING_SJLJ_EXCEPTIONS__ ++---------------------------------------------------------------------+ +| Beginning of Action Table ttypeIndex == 0 : cleanup | +| ... ttypeIndex > 0 : catch | +| ttypeIndex < 0 : exception spec | +| +--------------+-----------+--------------------------------------+ | +| | ttypeIndex | (SLEB128) | Index into type_info Table (1-based) | | +| | actionOffset | (SLEB128) | Offset into next Action Table entry | | +| +--------------+-----------+--------------------------------------+ | +| ... | ++---------------------------------------------------------------------+-----------------+ +| type_info Table, but classInfoOffset does *not* point here! | +| +----------------+------------------------------------------------+-----------------+ | +| | Nth type_info* | Encoded with ttypeEncoding, 0 means catch(...) | ttypeIndex == N | | +| +----------------+------------------------------------------------+-----------------+ | +| ... | +| +----------------+------------------------------------------------+-----------------+ | +| | 1st type_info* | Encoded with ttypeEncoding, 0 means catch(...) | ttypeIndex == 1 | | +| +----------------+------------------------------------------------+-----------------+ | +| +---------------------------------------+-----------+------------------------------+ | +| | 1st ttypeIndex for 1st exception spec | (ULEB128) | classInfoOffset points here! | | +| | ... | (ULEB128) | | | +| | Mth ttypeIndex for 1st exception spec | (ULEB128) | | | +| | 0 | (ULEB128) | | | +| +---------------------------------------+------------------------------------------+ | +| ... | +| +---------------------------------------+------------------------------------------+ | +| | 0 | (ULEB128) | throw() | | +| +---------------------------------------+------------------------------------------+ | +| ... | +| +---------------------------------------+------------------------------------------+ | +| | 1st ttypeIndex for Nth exception spec | (ULEB128) | | | +| | ... | (ULEB128) | | | +| | Mth ttypeIndex for Nth exception spec | (ULEB128) | | | +| | 0 | (ULEB128) | | | +| +---------------------------------------+------------------------------------------+ | ++---------------------------------------------------------------------------------------+ + +Notes: + +* ttypeIndex in the Action Table, and in the exception spec table, is an index, + not a byte count, if positive. It is a negative index offset of + classInfoOffset and the sizeof entry depends on ttypeEncoding. + But if ttypeIndex is negative, it is a positive 1-based byte offset into the + type_info Table. + And if ttypeIndex is zero, it refers to a catch (...). + +* landingPad can be 0, this implies there is nothing to be done. + +* landingPad != 0 and actionEntry == 0 implies a cleanup needs to be done + @landingPad. + +* A cleanup can also be found under landingPad != 0 and actionEntry != 0 in + the Action Table with ttypeIndex == 0. +*/ + +namespace __cxxabiv1 +{ + +namespace +{ + +template <class AsType> +uintptr_t readPointerHelper(const uint8_t*& p) { + AsType value; + memcpy(&value, p, sizeof(AsType)); + p += sizeof(AsType); + return static_cast<uintptr_t>(value); +} + +} // end namespace + +extern "C" +{ + +// private API + +// Heavily borrowed from llvm/examples/ExceptionDemo/ExceptionDemo.cpp + +// DWARF Constants +enum +{ + DW_EH_PE_absptr = 0x00, + DW_EH_PE_uleb128 = 0x01, + DW_EH_PE_udata2 = 0x02, + DW_EH_PE_udata4 = 0x03, + DW_EH_PE_udata8 = 0x04, + DW_EH_PE_sleb128 = 0x09, + DW_EH_PE_sdata2 = 0x0A, + DW_EH_PE_sdata4 = 0x0B, + DW_EH_PE_sdata8 = 0x0C, + DW_EH_PE_pcrel = 0x10, + DW_EH_PE_textrel = 0x20, + DW_EH_PE_datarel = 0x30, + DW_EH_PE_funcrel = 0x40, + DW_EH_PE_aligned = 0x50, + DW_EH_PE_indirect = 0x80, + DW_EH_PE_omit = 0xFF +}; + +/// Read a uleb128 encoded value and advance pointer +/// See Variable Length Data Appendix C in: +/// @link http://dwarfstd.org/Dwarf4.pdf @unlink +/// @param data reference variable holding memory pointer to decode from +/// @returns decoded value +static +uintptr_t +readULEB128(const uint8_t** data) +{ + uintptr_t result = 0; + uintptr_t shift = 0; + unsigned char byte; + const uint8_t *p = *data; + do + { + byte = *p++; + result |= static_cast<uintptr_t>(byte & 0x7F) << shift; + shift += 7; + } while (byte & 0x80); + *data = p; + return result; +} + +/// Read a sleb128 encoded value and advance pointer +/// See Variable Length Data Appendix C in: +/// @link http://dwarfstd.org/Dwarf4.pdf @unlink +/// @param data reference variable holding memory pointer to decode from +/// @returns decoded value +static +intptr_t +readSLEB128(const uint8_t** data) +{ + uintptr_t result = 0; + uintptr_t shift = 0; + unsigned char byte; + const uint8_t *p = *data; + do + { + byte = *p++; + result |= static_cast<uintptr_t>(byte & 0x7F) << shift; + shift += 7; + } while (byte & 0x80); + *data = p; + if ((byte & 0x40) && (shift < (sizeof(result) << 3))) + result |= static_cast<uintptr_t>(~0) << shift; + return static_cast<intptr_t>(result); +} + +/// Read a pointer encoded value and advance pointer +/// See Variable Length Data in: +/// @link http://dwarfstd.org/Dwarf3.pdf @unlink +/// @param data reference variable holding memory pointer to decode from +/// @param encoding dwarf encoding type +/// @returns decoded value +static +uintptr_t +readEncodedPointer(const uint8_t** data, uint8_t encoding) +{ + uintptr_t result = 0; + if (encoding == DW_EH_PE_omit) + return result; + const uint8_t* p = *data; + // first get value + switch (encoding & 0x0F) + { + case DW_EH_PE_absptr: + result = readPointerHelper<uintptr_t>(p); + break; + case DW_EH_PE_uleb128: + result = readULEB128(&p); + break; + case DW_EH_PE_sleb128: + result = static_cast<uintptr_t>(readSLEB128(&p)); + break; + case DW_EH_PE_udata2: + result = readPointerHelper<uint16_t>(p); + break; + case DW_EH_PE_udata4: + result = readPointerHelper<uint32_t>(p); + break; + case DW_EH_PE_udata8: + result = readPointerHelper<uint64_t>(p); + break; + case DW_EH_PE_sdata2: + result = readPointerHelper<int16_t>(p); + break; + case DW_EH_PE_sdata4: + result = readPointerHelper<int32_t>(p); + break; + case DW_EH_PE_sdata8: + result = readPointerHelper<int64_t>(p); + break; + default: + // not supported + abort(); + break; + } + // then add relative offset + switch (encoding & 0x70) + { + case DW_EH_PE_absptr: + // do nothing + break; + case DW_EH_PE_pcrel: + if (result) + result += (uintptr_t)(*data); + break; + case DW_EH_PE_textrel: + case DW_EH_PE_datarel: + case DW_EH_PE_funcrel: + case DW_EH_PE_aligned: + default: + // not supported + abort(); + break; + } + // then apply indirection + if (result && (encoding & DW_EH_PE_indirect)) + result = *((uintptr_t*)result); + *data = p; + return result; +} + +static +void +call_terminate(bool native_exception, _Unwind_Exception* unwind_exception) +{ + __cxa_begin_catch(unwind_exception); + if (native_exception) + { + // Use the stored terminate_handler if possible + __cxa_exception* exception_header = (__cxa_exception*)(unwind_exception+1) - 1; + std::__terminate(exception_header->terminateHandler); + } + std::terminate(); +} + +#if defined(_LIBCXXABI_ARM_EHABI) +static const void* read_target2_value(const void* ptr) +{ + uintptr_t offset = *reinterpret_cast<const uintptr_t*>(ptr); + if (!offset) + return 0; + // "ARM EABI provides a TARGET2 relocation to describe these typeinfo + // pointers. The reason being it allows their precise semantics to be + // deferred to the linker. For bare-metal they turn into absolute + // relocations. For linux they turn into GOT-REL relocations." + // https://gcc.gnu.org/ml/gcc-patches/2009-08/msg00264.html +#if defined(LIBCXXABI_BAREMETAL) + return reinterpret_cast<const void*>(reinterpret_cast<uintptr_t>(ptr) + + offset); +#else + return *reinterpret_cast<const void **>(reinterpret_cast<uintptr_t>(ptr) + + offset); +#endif +} + +static const __shim_type_info* +get_shim_type_info(uint64_t ttypeIndex, const uint8_t* classInfo, + uint8_t ttypeEncoding, bool native_exception, + _Unwind_Exception* unwind_exception) +{ + if (classInfo == 0) + { + // this should not happen. Indicates corrupted eh_table. + call_terminate(native_exception, unwind_exception); + } + + assert(((ttypeEncoding == DW_EH_PE_absptr) || // LLVM or GCC 4.6 + (ttypeEncoding == DW_EH_PE_pcrel) || // GCC 4.7 baremetal + (ttypeEncoding == (DW_EH_PE_pcrel | DW_EH_PE_indirect))) && // GCC 4.7 linux + "Unexpected TTypeEncoding"); + (void)ttypeEncoding; + + const uint8_t* ttypePtr = classInfo - ttypeIndex * sizeof(uintptr_t); + return reinterpret_cast<const __shim_type_info *>( + read_target2_value(ttypePtr)); +} +#else // !defined(_LIBCXXABI_ARM_EHABI) +static +const __shim_type_info* +get_shim_type_info(uint64_t ttypeIndex, const uint8_t* classInfo, + uint8_t ttypeEncoding, bool native_exception, + _Unwind_Exception* unwind_exception) +{ + if (classInfo == 0) + { + // this should not happen. Indicates corrupted eh_table. + call_terminate(native_exception, unwind_exception); + } + switch (ttypeEncoding & 0x0F) + { + case DW_EH_PE_absptr: + ttypeIndex *= sizeof(void*); + break; + case DW_EH_PE_udata2: + case DW_EH_PE_sdata2: + ttypeIndex *= 2; + break; + case DW_EH_PE_udata4: + case DW_EH_PE_sdata4: + ttypeIndex *= 4; + break; + case DW_EH_PE_udata8: + case DW_EH_PE_sdata8: + ttypeIndex *= 8; + break; + default: + // this should not happen. Indicates corrupted eh_table. + call_terminate(native_exception, unwind_exception); + } + classInfo -= ttypeIndex; + return (const __shim_type_info*)readEncodedPointer(&classInfo, ttypeEncoding); +} +#endif // !defined(_LIBCXXABI_ARM_EHABI) + +/* + This is checking a thrown exception type, excpType, against a possibly empty + list of catchType's which make up an exception spec. + + An exception spec acts like a catch handler, but in reverse. This "catch + handler" will catch an excpType if and only if none of the catchType's in + the list will catch a excpType. If any catchType in the list can catch an + excpType, then this exception spec does not catch the excpType. +*/ +#if defined(_LIBCXXABI_ARM_EHABI) +static +bool +exception_spec_can_catch(int64_t specIndex, const uint8_t* classInfo, + uint8_t ttypeEncoding, const __shim_type_info* excpType, + void* adjustedPtr, _Unwind_Exception* unwind_exception) +{ + if (classInfo == 0) + { + // this should not happen. Indicates corrupted eh_table. + call_terminate(false, unwind_exception); + } + + assert(((ttypeEncoding == DW_EH_PE_absptr) || // LLVM or GCC 4.6 + (ttypeEncoding == DW_EH_PE_pcrel) || // GCC 4.7 baremetal + (ttypeEncoding == (DW_EH_PE_pcrel | DW_EH_PE_indirect))) && // GCC 4.7 linux + "Unexpected TTypeEncoding"); + (void)ttypeEncoding; + + // specIndex is negative of 1-based byte offset into classInfo; + specIndex = -specIndex; + --specIndex; + const void** temp = reinterpret_cast<const void**>( + reinterpret_cast<uintptr_t>(classInfo) + + static_cast<uintptr_t>(specIndex) * sizeof(uintptr_t)); + // If any type in the spec list can catch excpType, return false, else return true + // adjustments to adjustedPtr are ignored. + while (true) + { + // ARM EHABI exception specification table (filter table) consists of + // several pointers which will directly point to the type info object + // (instead of ttypeIndex). The table will be terminated with 0. + const void** ttypePtr = temp++; + if (*ttypePtr == 0) + break; + // We can get the __shim_type_info simply by performing a + // R_ARM_TARGET2 relocation, and cast the result to __shim_type_info. + const __shim_type_info* catchType = + static_cast<const __shim_type_info*>(read_target2_value(ttypePtr)); + void* tempPtr = adjustedPtr; + if (catchType->can_catch(excpType, tempPtr)) + return false; + } + return true; +} +#else +static +bool +exception_spec_can_catch(int64_t specIndex, const uint8_t* classInfo, + uint8_t ttypeEncoding, const __shim_type_info* excpType, + void* adjustedPtr, _Unwind_Exception* unwind_exception) +{ + if (classInfo == 0) + { + // this should not happen. Indicates corrupted eh_table. + call_terminate(false, unwind_exception); + } + // specIndex is negative of 1-based byte offset into classInfo; + specIndex = -specIndex; + --specIndex; + const uint8_t* temp = classInfo + specIndex; + // If any type in the spec list can catch excpType, return false, else return true + // adjustments to adjustedPtr are ignored. + while (true) + { + uint64_t ttypeIndex = readULEB128(&temp); + if (ttypeIndex == 0) + break; + const __shim_type_info* catchType = get_shim_type_info(ttypeIndex, + classInfo, + ttypeEncoding, + true, + unwind_exception); + void* tempPtr = adjustedPtr; + if (catchType->can_catch(excpType, tempPtr)) + return false; + } + return true; +} +#endif + +static +void* +get_thrown_object_ptr(_Unwind_Exception* unwind_exception) +{ + // Even for foreign exceptions, the exception object is *probably* at unwind_exception + 1 + // Regardless, this library is prohibited from touching a foreign exception + void* adjustedPtr = unwind_exception + 1; + if (__getExceptionClass(unwind_exception) == kOurDependentExceptionClass) + adjustedPtr = ((__cxa_dependent_exception*)adjustedPtr - 1)->primaryException; + return adjustedPtr; +} + +namespace +{ + +struct scan_results +{ + int64_t ttypeIndex; // > 0 catch handler, < 0 exception spec handler, == 0 a cleanup + const uint8_t* actionRecord; // Currently unused. Retained to ease future maintenance. + const uint8_t* languageSpecificData; // Needed only for __cxa_call_unexpected + uintptr_t landingPad; // null -> nothing found, else something found + void* adjustedPtr; // Used in cxa_exception.cpp + _Unwind_Reason_Code reason; // One of _URC_FATAL_PHASE1_ERROR, + // _URC_FATAL_PHASE2_ERROR, + // _URC_CONTINUE_UNWIND, + // _URC_HANDLER_FOUND +}; + +} // unnamed namespace + +static +void +set_registers(_Unwind_Exception* unwind_exception, _Unwind_Context* context, + const scan_results& results) +{ +#if defined(__USING_SJLJ_EXCEPTIONS__) +#define __builtin_eh_return_data_regno(regno) regno +#endif + _Unwind_SetGR(context, __builtin_eh_return_data_regno(0), + reinterpret_cast<uintptr_t>(unwind_exception)); + _Unwind_SetGR(context, __builtin_eh_return_data_regno(1), + static_cast<uintptr_t>(results.ttypeIndex)); + _Unwind_SetIP(context, results.landingPad); +} + +/* + There are 3 types of scans needed: + + 1. Scan for handler with native or foreign exception. If handler found, + save state and return _URC_HANDLER_FOUND, else return _URC_CONTINUE_UNWIND. + May also report an error on invalid input. + May terminate for invalid exception table. + _UA_SEARCH_PHASE + + 2. Scan for handler with foreign exception. Must return _URC_HANDLER_FOUND, + or call terminate. + _UA_CLEANUP_PHASE && _UA_HANDLER_FRAME && !native_exception + + 3. Scan for cleanups. If a handler is found and this isn't forced unwind, + then terminate, otherwise ignore the handler and keep looking for cleanup. + If a cleanup is found, return _URC_HANDLER_FOUND, else return _URC_CONTINUE_UNWIND. + May also report an error on invalid input. + May terminate for invalid exception table. + _UA_CLEANUP_PHASE && !_UA_HANDLER_FRAME +*/ + +static void scan_eh_tab(scan_results &results, _Unwind_Action actions, + bool native_exception, + _Unwind_Exception *unwind_exception, + _Unwind_Context *context) { + // Initialize results to found nothing but an error + results.ttypeIndex = 0; + results.actionRecord = 0; + results.languageSpecificData = 0; + results.landingPad = 0; + results.adjustedPtr = 0; + results.reason = _URC_FATAL_PHASE1_ERROR; + // Check for consistent actions + if (actions & _UA_SEARCH_PHASE) + { + // Do Phase 1 + if (actions & (_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME | _UA_FORCE_UNWIND)) + { + // None of these flags should be set during Phase 1 + // Client error + results.reason = _URC_FATAL_PHASE1_ERROR; + return; + } + } + else if (actions & _UA_CLEANUP_PHASE) + { + if ((actions & _UA_HANDLER_FRAME) && (actions & _UA_FORCE_UNWIND)) + { + // _UA_HANDLER_FRAME should only be set if phase 1 found a handler. + // If _UA_FORCE_UNWIND is set, phase 1 shouldn't have happened. + // Client error + results.reason = _URC_FATAL_PHASE2_ERROR; + return; + } + } + else // Neither _UA_SEARCH_PHASE nor _UA_CLEANUP_PHASE is set + { + // One of these should be set. + // Client error + results.reason = _URC_FATAL_PHASE1_ERROR; + return; + } + // Start scan by getting exception table address + const uint8_t *lsda = (const uint8_t *)_Unwind_GetLanguageSpecificData(context); + if (lsda == 0) + { + // There is no exception table + results.reason = _URC_CONTINUE_UNWIND; + return; + } + results.languageSpecificData = lsda; + // Get the current instruction pointer and offset it before next + // instruction in the current frame which threw the exception. + uintptr_t ip = _Unwind_GetIP(context) - 1; + // Get beginning current frame's code (as defined by the + // emitted dwarf code) + uintptr_t funcStart = _Unwind_GetRegionStart(context); +#ifdef __USING_SJLJ_EXCEPTIONS__ + if (ip == uintptr_t(-1)) + { + // no action + results.reason = _URC_CONTINUE_UNWIND; + return; + } + else if (ip == 0) + call_terminate(native_exception, unwind_exception); + // ip is 1-based index into call site table +#else // !__USING_SJLJ_EXCEPTIONS__ + uintptr_t ipOffset = ip - funcStart; +#endif // !defined(_USING_SLJL_EXCEPTIONS__) + const uint8_t* classInfo = NULL; + // Note: See JITDwarfEmitter::EmitExceptionTable(...) for corresponding + // dwarf emission + // Parse LSDA header. + uint8_t lpStartEncoding = *lsda++; + const uint8_t* lpStart = (const uint8_t*)readEncodedPointer(&lsda, lpStartEncoding); + if (lpStart == 0) + lpStart = (const uint8_t*)funcStart; + uint8_t ttypeEncoding = *lsda++; + if (ttypeEncoding != DW_EH_PE_omit) + { + // Calculate type info locations in emitted dwarf code which + // were flagged by type info arguments to llvm.eh.selector + // intrinsic + uintptr_t classInfoOffset = readULEB128(&lsda); + classInfo = lsda + classInfoOffset; + } + // Walk call-site table looking for range that + // includes current PC. + uint8_t callSiteEncoding = *lsda++; +#ifdef __USING_SJLJ_EXCEPTIONS__ + (void)callSiteEncoding; // When using SjLj exceptions, callSiteEncoding is never used +#endif + uint32_t callSiteTableLength = static_cast<uint32_t>(readULEB128(&lsda)); + const uint8_t* callSiteTableStart = lsda; + const uint8_t* callSiteTableEnd = callSiteTableStart + callSiteTableLength; + const uint8_t* actionTableStart = callSiteTableEnd; + const uint8_t* callSitePtr = callSiteTableStart; + while (callSitePtr < callSiteTableEnd) + { + // There is one entry per call site. +#ifndef __USING_SJLJ_EXCEPTIONS__ + // The call sites are non-overlapping in [start, start+length) + // The call sites are ordered in increasing value of start + uintptr_t start = readEncodedPointer(&callSitePtr, callSiteEncoding); + uintptr_t length = readEncodedPointer(&callSitePtr, callSiteEncoding); + uintptr_t landingPad = readEncodedPointer(&callSitePtr, callSiteEncoding); + uintptr_t actionEntry = readULEB128(&callSitePtr); + if ((start <= ipOffset) && (ipOffset < (start + length))) +#else // __USING_SJLJ_EXCEPTIONS__ + // ip is 1-based index into this table + uintptr_t landingPad = readULEB128(&callSitePtr); + uintptr_t actionEntry = readULEB128(&callSitePtr); + if (--ip == 0) +#endif // __USING_SJLJ_EXCEPTIONS__ + { + // Found the call site containing ip. +#ifndef __USING_SJLJ_EXCEPTIONS__ + if (landingPad == 0) + { + // No handler here + results.reason = _URC_CONTINUE_UNWIND; + return; + } + landingPad = (uintptr_t)lpStart + landingPad; +#else // __USING_SJLJ_EXCEPTIONS__ + ++landingPad; +#endif // __USING_SJLJ_EXCEPTIONS__ + if (actionEntry == 0) + { + // Found a cleanup + // If this is a type 1 or type 2 search, there are no handlers + // If this is a type 3 search, you want to install the cleanup. + if ((actions & _UA_CLEANUP_PHASE) && !(actions & _UA_HANDLER_FRAME)) + { + results.ttypeIndex = 0; // Redundant but clarifying + results.landingPad = landingPad; + results.reason = _URC_HANDLER_FOUND; + return; + } + // No handler here + results.reason = _URC_CONTINUE_UNWIND; + return; + } + // Convert 1-based byte offset into + const uint8_t* action = actionTableStart + (actionEntry - 1); + // Scan action entries until you find a matching handler, cleanup, or the end of action list + while (true) + { + const uint8_t* actionRecord = action; + int64_t ttypeIndex = readSLEB128(&action); + if (ttypeIndex > 0) + { + // Found a catch, does it actually catch? + // First check for catch (...) + const __shim_type_info* catchType = + get_shim_type_info(static_cast<uint64_t>(ttypeIndex), + classInfo, ttypeEncoding, + native_exception, unwind_exception); + if (catchType == 0) + { + // Found catch (...) catches everything, including foreign exceptions + // If this is a type 1 search save state and return _URC_HANDLER_FOUND + // If this is a type 2 search save state and return _URC_HANDLER_FOUND + // If this is a type 3 search !_UA_FORCE_UNWIND, we should have found this in phase 1! + // If this is a type 3 search _UA_FORCE_UNWIND, ignore handler and continue scan + if ((actions & _UA_SEARCH_PHASE) || (actions & _UA_HANDLER_FRAME)) + { + // Save state and return _URC_HANDLER_FOUND + results.ttypeIndex = ttypeIndex; + results.actionRecord = actionRecord; + results.landingPad = landingPad; + results.adjustedPtr = get_thrown_object_ptr(unwind_exception); + results.reason = _URC_HANDLER_FOUND; + return; + } + else if (!(actions & _UA_FORCE_UNWIND)) + { + // It looks like the exception table has changed + // on us. Likely stack corruption! + call_terminate(native_exception, unwind_exception); + } + } + // Else this is a catch (T) clause and will never + // catch a foreign exception + else if (native_exception) + { + __cxa_exception* exception_header = (__cxa_exception*)(unwind_exception+1) - 1; + void* adjustedPtr = get_thrown_object_ptr(unwind_exception); + const __shim_type_info* excpType = + static_cast<const __shim_type_info*>(exception_header->exceptionType); + if (adjustedPtr == 0 || excpType == 0) + { + // Something very bad happened + call_terminate(native_exception, unwind_exception); + } + if (catchType->can_catch(excpType, adjustedPtr)) + { + // Found a matching handler + // If this is a type 1 search save state and return _URC_HANDLER_FOUND + // If this is a type 3 search and !_UA_FORCE_UNWIND, we should have found this in phase 1! + // If this is a type 3 search and _UA_FORCE_UNWIND, ignore handler and continue scan + if (actions & _UA_SEARCH_PHASE) + { + // Save state and return _URC_HANDLER_FOUND + results.ttypeIndex = ttypeIndex; + results.actionRecord = actionRecord; + results.landingPad = landingPad; + results.adjustedPtr = adjustedPtr; + results.reason = _URC_HANDLER_FOUND; + return; + } + else if (!(actions & _UA_FORCE_UNWIND)) + { + // It looks like the exception table has changed + // on us. Likely stack corruption! + call_terminate(native_exception, unwind_exception); + } + } + } + // Scan next action ... + } + else if (ttypeIndex < 0) + { + // Found an exception spec. If this is a foreign exception, + // it is always caught. + if (native_exception) + { + // Does the exception spec catch this native exception? + __cxa_exception* exception_header = (__cxa_exception*)(unwind_exception+1) - 1; + void* adjustedPtr = get_thrown_object_ptr(unwind_exception); + const __shim_type_info* excpType = + static_cast<const __shim_type_info*>(exception_header->exceptionType); + if (adjustedPtr == 0 || excpType == 0) + { + // Something very bad happened + call_terminate(native_exception, unwind_exception); + } + if (exception_spec_can_catch(ttypeIndex, classInfo, + ttypeEncoding, excpType, + adjustedPtr, unwind_exception)) + { + // native exception caught by exception spec + // If this is a type 1 search, save state and return _URC_HANDLER_FOUND + // If this is a type 3 search !_UA_FORCE_UNWIND, we should have found this in phase 1! + // If this is a type 3 search _UA_FORCE_UNWIND, ignore handler and continue scan + if (actions & _UA_SEARCH_PHASE) + { + // Save state and return _URC_HANDLER_FOUND + results.ttypeIndex = ttypeIndex; + results.actionRecord = actionRecord; + results.landingPad = landingPad; + results.adjustedPtr = adjustedPtr; + results.reason = _URC_HANDLER_FOUND; + return; + } + else if (!(actions & _UA_FORCE_UNWIND)) + { + // It looks like the exception table has changed + // on us. Likely stack corruption! + call_terminate(native_exception, unwind_exception); + } + } + } + else + { + // foreign exception caught by exception spec + // If this is a type 1 search, save state and return _URC_HANDLER_FOUND + // If this is a type 2 search, save state and return _URC_HANDLER_FOUND + // If this is a type 3 search !_UA_FORCE_UNWIND, we should have found this in phase 1! + // If this is a type 3 search _UA_FORCE_UNWIND, ignore handler and continue scan + if ((actions & _UA_SEARCH_PHASE) || (actions & _UA_HANDLER_FRAME)) + { + // Save state and return _URC_HANDLER_FOUND + results.ttypeIndex = ttypeIndex; + results.actionRecord = actionRecord; + results.landingPad = landingPad; + results.adjustedPtr = get_thrown_object_ptr(unwind_exception); + results.reason = _URC_HANDLER_FOUND; + return; + } + else if (!(actions & _UA_FORCE_UNWIND)) + { + // It looks like the exception table has changed + // on us. Likely stack corruption! + call_terminate(native_exception, unwind_exception); + } + } + // Scan next action ... + } + else // ttypeIndex == 0 + { + // Found a cleanup + // If this is a type 1 search, ignore it and continue scan + // If this is a type 2 search, ignore it and continue scan + // If this is a type 3 search, save state and return _URC_HANDLER_FOUND + if ((actions & _UA_CLEANUP_PHASE) && !(actions & _UA_HANDLER_FRAME)) + { + // Save state and return _URC_HANDLER_FOUND + results.ttypeIndex = ttypeIndex; + results.actionRecord = actionRecord; + results.landingPad = landingPad; + results.adjustedPtr = get_thrown_object_ptr(unwind_exception); + results.reason = _URC_HANDLER_FOUND; + return; + } + } + const uint8_t* temp = action; + int64_t actionOffset = readSLEB128(&temp); + if (actionOffset == 0) + { + // End of action list, no matching handler or cleanup found + results.reason = _URC_CONTINUE_UNWIND; + return; + } + // Go to next action + action += actionOffset; + } // there is no break out of this loop, only return + } +#ifndef __USING_SJLJ_EXCEPTIONS__ + else if (ipOffset < start) + { + // There is no call site for this ip + // Something bad has happened. We should never get here. + // Possible stack corruption. + call_terminate(native_exception, unwind_exception); + } +#endif // !__USING_SJLJ_EXCEPTIONS__ + } // there might be some tricky cases which break out of this loop + + // It is possible that no eh table entry specify how to handle + // this exception. By spec, terminate it immediately. + call_terminate(native_exception, unwind_exception); +} + +// public API + +/* +The personality function branches on actions like so: + +_UA_SEARCH_PHASE + + If _UA_CLEANUP_PHASE or _UA_HANDLER_FRAME or _UA_FORCE_UNWIND there's + an error from above, return _URC_FATAL_PHASE1_ERROR. + + Scan for anything that could stop unwinding: + + 1. A catch clause that will catch this exception + (will never catch foreign). + 2. A catch (...) (will always catch foreign). + 3. An exception spec that will catch this exception + (will always catch foreign). + If a handler is found + If not foreign + Save state in header + return _URC_HANDLER_FOUND + Else a handler not found + return _URC_CONTINUE_UNWIND + +_UA_CLEANUP_PHASE + + If _UA_HANDLER_FRAME + If _UA_FORCE_UNWIND + How did this happen? return _URC_FATAL_PHASE2_ERROR + If foreign + Do _UA_SEARCH_PHASE to recover state + else + Recover state from header + Transfer control to landing pad. return _URC_INSTALL_CONTEXT + + Else + + This branch handles both normal C++ non-catching handlers (cleanups) + and forced unwinding. + Scan for anything that can not stop unwinding: + + 1. A cleanup. + + If a cleanup is found + transfer control to it. return _URC_INSTALL_CONTEXT + Else a cleanup is not found: return _URC_CONTINUE_UNWIND +*/ + +#if !defined(_LIBCXXABI_ARM_EHABI) +#if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) +static _Unwind_Reason_Code __gxx_personality_imp +#else +_LIBCXXABI_FUNC_VIS _Unwind_Reason_Code +#ifdef __USING_SJLJ_EXCEPTIONS__ +__gxx_personality_sj0 +#else +__gxx_personality_v0 +#endif +#endif + (int version, _Unwind_Action actions, uint64_t exceptionClass, + _Unwind_Exception* unwind_exception, _Unwind_Context* context) +{ + if (version != 1 || unwind_exception == 0 || context == 0) + return _URC_FATAL_PHASE1_ERROR; + + bool native_exception = (exceptionClass & get_vendor_and_language) == + (kOurExceptionClass & get_vendor_and_language); + scan_results results; + if (actions & _UA_SEARCH_PHASE) + { + // Phase 1 search: All we're looking for in phase 1 is a handler that + // halts unwinding + scan_eh_tab(results, actions, native_exception, unwind_exception, context); + if (results.reason == _URC_HANDLER_FOUND) + { + // Found one. Can we cache the results somewhere to optimize phase 2? + if (native_exception) + { + __cxa_exception* exception_header = (__cxa_exception*)(unwind_exception+1) - 1; + exception_header->handlerSwitchValue = static_cast<int>(results.ttypeIndex); + exception_header->actionRecord = results.actionRecord; + exception_header->languageSpecificData = results.languageSpecificData; + exception_header->catchTemp = reinterpret_cast<void*>(results.landingPad); + exception_header->adjustedPtr = results.adjustedPtr; + } + return _URC_HANDLER_FOUND; + } + // Did not find a catching-handler. Return the results of the scan + // (normally _URC_CONTINUE_UNWIND, but could have been _URC_FATAL_PHASE1_ERROR + // if we were called improperly). + return results.reason; + } + if (actions & _UA_CLEANUP_PHASE) + { + // Phase 2 search: + // Did we find a catching handler in phase 1? + if (actions & _UA_HANDLER_FRAME) + { + // Yes, phase 1 said we have a catching handler here. + // Did we cache the results of the scan? + if (native_exception) + { + // Yes, reload the results from the cache. + __cxa_exception* exception_header = (__cxa_exception*)(unwind_exception+1) - 1; + results.ttypeIndex = exception_header->handlerSwitchValue; + results.actionRecord = exception_header->actionRecord; + results.languageSpecificData = exception_header->languageSpecificData; + results.landingPad = reinterpret_cast<uintptr_t>(exception_header->catchTemp); + results.adjustedPtr = exception_header->adjustedPtr; + } + else + { + // No, do the scan again to reload the results. + scan_eh_tab(results, actions, native_exception, unwind_exception, context); + // Phase 1 told us we would find a handler. Now in Phase 2 we + // didn't find a handler. The eh table should not be changing! + if (results.reason != _URC_HANDLER_FOUND) + call_terminate(native_exception, unwind_exception); + } + // Jump to the handler + set_registers(unwind_exception, context, results); + return _URC_INSTALL_CONTEXT; + } + // Either we didn't do a phase 1 search (due to forced unwinding), or + // phase 1 reported no catching-handlers. + // Search for a (non-catching) cleanup + scan_eh_tab(results, actions, native_exception, unwind_exception, context); + if (results.reason == _URC_HANDLER_FOUND) + { + // Found a non-catching handler. Jump to it: + set_registers(unwind_exception, context, results); + return _URC_INSTALL_CONTEXT; + } + // Did not find a cleanup. Return the results of the scan + // (normally _URC_CONTINUE_UNWIND, but could have been _URC_FATAL_PHASE2_ERROR + // if we were called improperly). + return results.reason; + } + // We were called improperly: neither a phase 1 or phase 2 search + return _URC_FATAL_PHASE1_ERROR; +} + +#if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) +extern "C" _LIBCXXABI_FUNC_VIS 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 + +#else + +extern "C" _Unwind_Reason_Code __gnu_unwind_frame(_Unwind_Exception*, + _Unwind_Context*); + +// Helper function to unwind one frame. +// ARM EHABI 7.3 and 7.4: If the personality function returns _URC_CONTINUE_UNWIND, the +// personality routine should update the virtual register set (VRS) according to the +// corresponding frame unwinding instructions (ARM EHABI 9.3.) +static _Unwind_Reason_Code continue_unwind(_Unwind_Exception* unwind_exception, + _Unwind_Context* context) +{ + if (__gnu_unwind_frame(unwind_exception, context) != _URC_OK) + return _URC_FAILURE; + return _URC_CONTINUE_UNWIND; +} + +// ARM register names +#if !defined(LIBCXXABI_USE_LLVM_UNWINDER) +static const uint32_t REG_UCB = 12; // Register to save _Unwind_Control_Block +#endif +static const uint32_t REG_SP = 13; + +static void save_results_to_barrier_cache(_Unwind_Exception* unwind_exception, + const scan_results& results) +{ + unwind_exception->barrier_cache.bitpattern[0] = (uint32_t)results.adjustedPtr; + unwind_exception->barrier_cache.bitpattern[1] = (uint32_t)results.actionRecord; + unwind_exception->barrier_cache.bitpattern[2] = (uint32_t)results.languageSpecificData; + unwind_exception->barrier_cache.bitpattern[3] = (uint32_t)results.landingPad; + unwind_exception->barrier_cache.bitpattern[4] = (uint32_t)results.ttypeIndex; +} + +static void load_results_from_barrier_cache(scan_results& results, + const _Unwind_Exception* unwind_exception) +{ + results.adjustedPtr = (void*)unwind_exception->barrier_cache.bitpattern[0]; + results.actionRecord = (const uint8_t*)unwind_exception->barrier_cache.bitpattern[1]; + results.languageSpecificData = (const uint8_t*)unwind_exception->barrier_cache.bitpattern[2]; + results.landingPad = (uintptr_t)unwind_exception->barrier_cache.bitpattern[3]; + results.ttypeIndex = (int64_t)(int32_t)unwind_exception->barrier_cache.bitpattern[4]; +} + +extern "C" _LIBCXXABI_FUNC_VIS _Unwind_Reason_Code +__gxx_personality_v0(_Unwind_State state, + _Unwind_Exception* unwind_exception, + _Unwind_Context* context) +{ + if (unwind_exception == 0 || context == 0) + return _URC_FATAL_PHASE1_ERROR; + + bool native_exception = __isOurExceptionClass(unwind_exception); + +#if !defined(LIBCXXABI_USE_LLVM_UNWINDER) + // Copy the address of _Unwind_Control_Block to r12 so that + // _Unwind_GetLanguageSpecificData() and _Unwind_GetRegionStart() can + // return correct address. + _Unwind_SetGR(context, REG_UCB, reinterpret_cast<uint32_t>(unwind_exception)); +#endif + + // Check the undocumented force unwinding behavior + bool is_force_unwinding = state & _US_FORCE_UNWIND; + state &= ~_US_FORCE_UNWIND; + + scan_results results; + switch (state) { + case _US_VIRTUAL_UNWIND_FRAME: + if (is_force_unwinding) + return continue_unwind(unwind_exception, context); + + // Phase 1 search: All we're looking for in phase 1 is a handler that halts unwinding + scan_eh_tab(results, _UA_SEARCH_PHASE, native_exception, unwind_exception, context); + if (results.reason == _URC_HANDLER_FOUND) + { + unwind_exception->barrier_cache.sp = _Unwind_GetGR(context, REG_SP); + if (native_exception) + save_results_to_barrier_cache(unwind_exception, results); + return _URC_HANDLER_FOUND; + } + // Did not find the catch handler + if (results.reason == _URC_CONTINUE_UNWIND) + return continue_unwind(unwind_exception, context); + return results.reason; + + case _US_UNWIND_FRAME_STARTING: + // TODO: Support force unwinding in the phase 2 search. + // NOTE: In order to call the cleanup functions, _Unwind_ForcedUnwind() + // will call this personality function with (_US_FORCE_UNWIND | + // _US_UNWIND_FRAME_STARTING). + + // Phase 2 search + if (unwind_exception->barrier_cache.sp == _Unwind_GetGR(context, REG_SP)) + { + // Found a catching handler in phase 1 + if (native_exception) + { + // Load the result from the native exception barrier cache. + load_results_from_barrier_cache(results, unwind_exception); + results.reason = _URC_HANDLER_FOUND; + } + else + { + // Search for the catching handler again for the foreign exception. + scan_eh_tab(results, static_cast<_Unwind_Action>(_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME), + native_exception, unwind_exception, context); + if (results.reason != _URC_HANDLER_FOUND) // phase1 search should guarantee to find one + call_terminate(native_exception, unwind_exception); + } + + // Install the context for the catching handler + set_registers(unwind_exception, context, results); + return _URC_INSTALL_CONTEXT; + } + + // Either we didn't do a phase 1 search (due to forced unwinding), or + // phase 1 reported no catching-handlers. + // Search for a (non-catching) cleanup + scan_eh_tab(results, _UA_CLEANUP_PHASE, native_exception, unwind_exception, context); + if (results.reason == _URC_HANDLER_FOUND) + { + // Found a non-catching handler + + // ARM EHABI 8.4.2: Before we can jump to the cleanup handler, we have to setup some + // internal data structures, so that __cxa_end_cleanup() can get unwind_exception from + // __cxa_get_globals(). + __cxa_begin_cleanup(unwind_exception); + + // Install the context for the cleanup handler + set_registers(unwind_exception, context, results); + return _URC_INSTALL_CONTEXT; + } + + // Did not find any handler + if (results.reason == _URC_CONTINUE_UNWIND) + return continue_unwind(unwind_exception, context); + return results.reason; + + case _US_UNWIND_FRAME_RESUME: + return continue_unwind(unwind_exception, context); + } + + // We were called improperly: neither a phase 1 or phase 2 search + return _URC_FATAL_PHASE1_ERROR; +} +#endif + + +__attribute__((noreturn)) +_LIBCXXABI_FUNC_VIS void +__cxa_call_unexpected(void* arg) +{ + _Unwind_Exception* unwind_exception = static_cast<_Unwind_Exception*>(arg); + if (unwind_exception == 0) + call_terminate(false, unwind_exception); + __cxa_begin_catch(unwind_exception); + bool native_old_exception = __isOurExceptionClass(unwind_exception); + std::unexpected_handler u_handler; + std::terminate_handler t_handler; + __cxa_exception* old_exception_header = 0; + int64_t ttypeIndex; + const uint8_t* lsda; + if (native_old_exception) + { + old_exception_header = (__cxa_exception*)(unwind_exception+1) - 1; + t_handler = old_exception_header->terminateHandler; + u_handler = old_exception_header->unexpectedHandler; + // If std::__unexpected(u_handler) rethrows the same exception, + // these values get overwritten by the rethrow. So save them now: +#if defined(_LIBCXXABI_ARM_EHABI) + ttypeIndex = (int64_t)(int32_t)unwind_exception->barrier_cache.bitpattern[4]; + lsda = (const uint8_t*)unwind_exception->barrier_cache.bitpattern[2]; +#else + ttypeIndex = old_exception_header->handlerSwitchValue; + lsda = old_exception_header->languageSpecificData; +#endif + } + else + { + t_handler = std::get_terminate(); + u_handler = std::get_unexpected(); + } + try + { + std::__unexpected(u_handler); + } + catch (...) + { + // If the old exception is foreign, then all we can do is terminate. + // We have no way to recover the needed old exception spec. There's + // no way to pass that information here. And the personality routine + // can't call us directly and do anything but terminate() if we throw + // from here. + if (native_old_exception) + { + // Have: + // old_exception_header->languageSpecificData + // old_exception_header->actionRecord + // Need + // const uint8_t* classInfo + // uint8_t ttypeEncoding + uint8_t lpStartEncoding = *lsda++; + const uint8_t* lpStart = (const uint8_t*)readEncodedPointer(&lsda, lpStartEncoding); + (void)lpStart; // purposefully unused. Just needed to increment lsda. + uint8_t ttypeEncoding = *lsda++; + if (ttypeEncoding == DW_EH_PE_omit) + std::__terminate(t_handler); + uintptr_t classInfoOffset = readULEB128(&lsda); + const uint8_t* classInfo = lsda + classInfoOffset; + // Is this new exception catchable by the exception spec at ttypeIndex? + // The answer is obviously yes if the new and old exceptions are the same exception + // If no + // throw; + __cxa_eh_globals* globals = __cxa_get_globals_fast(); + __cxa_exception* new_exception_header = globals->caughtExceptions; + if (new_exception_header == 0) + // This shouldn't be able to happen! + std::__terminate(t_handler); + bool native_new_exception = __isOurExceptionClass(&new_exception_header->unwindHeader); + void* adjustedPtr; + if (native_new_exception && (new_exception_header != old_exception_header)) + { + const __shim_type_info* excpType = + static_cast<const __shim_type_info*>(new_exception_header->exceptionType); + adjustedPtr = + __getExceptionClass(&new_exception_header->unwindHeader) == kOurDependentExceptionClass ? + ((__cxa_dependent_exception*)new_exception_header)->primaryException : + new_exception_header + 1; + if (!exception_spec_can_catch(ttypeIndex, classInfo, ttypeEncoding, + excpType, adjustedPtr, unwind_exception)) + { + // We need to __cxa_end_catch, but for the old exception, + // not the new one. This is a little tricky ... + // Disguise new_exception_header as a rethrown exception, but + // don't actually rethrow it. This means you can temporarily + // end the catch clause enclosing new_exception_header without + // __cxa_end_catch destroying new_exception_header. + new_exception_header->handlerCount = -new_exception_header->handlerCount; + globals->uncaughtExceptions += 1; + // Call __cxa_end_catch for new_exception_header + __cxa_end_catch(); + // Call __cxa_end_catch for old_exception_header + __cxa_end_catch(); + // Renter this catch clause with new_exception_header + __cxa_begin_catch(&new_exception_header->unwindHeader); + // Rethrow new_exception_header + throw; + } + } + // Will a std::bad_exception be catchable by the exception spec at + // ttypeIndex? + // If no + // throw std::bad_exception(); + const __shim_type_info* excpType = + static_cast<const __shim_type_info*>(&typeid(std::bad_exception)); + std::bad_exception be; + adjustedPtr = &be; + if (!exception_spec_can_catch(ttypeIndex, classInfo, ttypeEncoding, + excpType, adjustedPtr, unwind_exception)) + { + // We need to __cxa_end_catch for both the old exception and the + // new exception. Technically we should do it in that order. + // But it is expedient to do it in the opposite order: + // Call __cxa_end_catch for new_exception_header + __cxa_end_catch(); + // Throw std::bad_exception will __cxa_end_catch for + // old_exception_header + throw be; + } + } + } + std::__terminate(t_handler); +} + +} // extern "C" + +} // __cxxabiv1