Date: Thu, 5 May 2016 22:30:00 +0000 (UTC) From: Dimitry Andric <dim@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r299143 - head/contrib/libcxxrt Message-ID: <201605052230.u45MU09F093897@repo.freebsd.org>
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Author: dim Date: Thu May 5 22:30:00 2016 New Revision: 299143 URL: https://svnweb.freebsd.org/changeset/base/299143 Log: Since contrib/libcxxrt's ancestry was never correct, subversion 1.8 and higher cannot merge to it from the vendor area. Re-bootstrap the ancestry by doing (apologies to your retinas): * svn pg svn:mergeinfo contrib/libcxxrt > mergeinfo.txt * svn rm contrib/libcxxrt * svn cp ^/vendor/libcxxrt/dist@297299 contrib/libcxxrt * svn rm CMakeLists.txt doxygen_config * svn cp ^/head/contrib/libcxxrt/FREEBSD-upgrade@297299 contrib/libcxxrt * svn cp ^/head/contrib/libcxxrt/exception.cc@297299 contrib/libcxxrt * svn cp ^/head/contrib/libcxxrt/unwind-arm.h@297299 contrib/libcxxrt * svn pd -R svn:mergeinfo contrib/libcxxrt * svn ps -F mergeinfo.txt svn:mergeinfo contrib/libcxxrt Added: head/contrib/libcxxrt/FREEBSD-upgrade - copied unchanged from r297299, head/contrib/libcxxrt/FREEBSD-upgrade Replaced: - copied from r297299, vendor/libcxxrt/dist/ head/contrib/libcxxrt/exception.cc - copied unchanged from r297299, head/contrib/libcxxrt/exception.cc head/contrib/libcxxrt/unwind-arm.h - copied unchanged from r297299, head/contrib/libcxxrt/unwind-arm.h Directory Properties: head/contrib/libcxxrt/ (props changed) Deleted: head/contrib/libcxxrt/CMakeLists.txt head/contrib/libcxxrt/doxygen_config Copied: head/contrib/libcxxrt/FREEBSD-upgrade (from r297299, head/contrib/libcxxrt/FREEBSD-upgrade) ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ head/contrib/libcxxrt/FREEBSD-upgrade Thu May 5 22:30:00 2016 (r299143, copy of r297299, head/contrib/libcxxrt/FREEBSD-upgrade) @@ -0,0 +1,6 @@ +$FreeBSD$ + +This is the FreeBSD copy of libcxxrt. It contains the src directory from the +upstream repository. + +When updating, copy *.{c,cc,h} from the upstream src/. Copied: head/contrib/libcxxrt/exception.cc (from r297299, head/contrib/libcxxrt/exception.cc) ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ head/contrib/libcxxrt/exception.cc Thu May 5 22:30:00 2016 (r299143, copy of r297299, head/contrib/libcxxrt/exception.cc) @@ -0,0 +1,1544 @@ +/* + * Copyright 2010-2011 PathScale, Inc. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS + * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; + * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <stdlib.h> +#include <dlfcn.h> +#include <stdio.h> +#include <string.h> +#include <stdint.h> +#include <pthread.h> +#include "typeinfo.h" +#include "dwarf_eh.h" +#include "atomic.h" +#include "cxxabi.h" + +#pragma weak pthread_key_create +#pragma weak pthread_setspecific +#pragma weak pthread_getspecific +#pragma weak pthread_once +#ifdef LIBCXXRT_WEAK_LOCKS +#pragma weak pthread_mutex_lock +#define pthread_mutex_lock(mtx) do {\ + if (pthread_mutex_lock) pthread_mutex_lock(mtx);\ + } while(0) +#pragma weak pthread_mutex_unlock +#define pthread_mutex_unlock(mtx) do {\ + if (pthread_mutex_unlock) pthread_mutex_unlock(mtx);\ + } while(0) +#pragma weak pthread_cond_signal +#define pthread_cond_signal(cv) do {\ + if (pthread_cond_signal) pthread_cond_signal(cv);\ + } while(0) +#pragma weak pthread_cond_wait +#define pthread_cond_wait(cv, mtx) do {\ + if (pthread_cond_wait) pthread_cond_wait(cv, mtx);\ + } while(0) +#endif + +using namespace ABI_NAMESPACE; + +/** + * Saves the result of the landing pad that we have found. For ARM, this is + * stored in the generic unwind structure, while on other platforms it is + * stored in the C++ exception. + */ +static void saveLandingPad(struct _Unwind_Context *context, + struct _Unwind_Exception *ucb, + struct __cxa_exception *ex, + int selector, + dw_eh_ptr_t landingPad) +{ +#if defined(__arm__) && !defined(__ARM_DWARF_EH__) + // On ARM, we store the saved exception in the generic part of the structure + ucb->barrier_cache.sp = _Unwind_GetGR(context, 13); + ucb->barrier_cache.bitpattern[1] = static_cast<uint32_t>(selector); + ucb->barrier_cache.bitpattern[3] = reinterpret_cast<uint32_t>(landingPad); +#endif + // Cache the results for the phase 2 unwind, if we found a handler + // and this is not a foreign exception. + if (ex) + { + ex->handlerSwitchValue = selector; + ex->catchTemp = landingPad; + } +} + +/** + * Loads the saved landing pad. Returns 1 on success, 0 on failure. + */ +static int loadLandingPad(struct _Unwind_Context *context, + struct _Unwind_Exception *ucb, + struct __cxa_exception *ex, + unsigned long *selector, + dw_eh_ptr_t *landingPad) +{ +#if defined(__arm__) && !defined(__ARM_DWARF_EH__) + *selector = ucb->barrier_cache.bitpattern[1]; + *landingPad = reinterpret_cast<dw_eh_ptr_t>(ucb->barrier_cache.bitpattern[3]); + return 1; +#else + if (ex) + { + *selector = ex->handlerSwitchValue; + *landingPad = reinterpret_cast<dw_eh_ptr_t>(ex->catchTemp); + return 0; + } + return 0; +#endif +} + +static inline _Unwind_Reason_Code continueUnwinding(struct _Unwind_Exception *ex, + struct _Unwind_Context *context) +{ +#if defined(__arm__) && !defined(__ARM_DWARF_EH__) + if (__gnu_unwind_frame(ex, context) != _URC_OK) { return _URC_FAILURE; } +#endif + return _URC_CONTINUE_UNWIND; +} + + +extern "C" void __cxa_free_exception(void *thrown_exception); +extern "C" void __cxa_free_dependent_exception(void *thrown_exception); +extern "C" void* __dynamic_cast(const void *sub, + const __class_type_info *src, + const __class_type_info *dst, + ptrdiff_t src2dst_offset); + +/** + * The type of a handler that has been found. + */ +typedef enum +{ + /** No handler. */ + handler_none, + /** + * A cleanup - the exception will propagate through this frame, but code + * must be run when this happens. + */ + handler_cleanup, + /** + * A catch statement. The exception will not propagate past this frame + * (without an explicit rethrow). + */ + handler_catch +} handler_type; + +/** + * Per-thread info required by the runtime. We store a single structure + * pointer in thread-local storage, because this tends to be a scarce resource + * and it's impolite to steal all of it and not leave any for the rest of the + * program. + * + * Instances of this structure are allocated lazily - at most one per thread - + * and are destroyed on thread termination. + */ +struct __cxa_thread_info +{ + /** The termination handler for this thread. */ + terminate_handler terminateHandler; + /** The unexpected exception handler for this thread. */ + unexpected_handler unexpectedHandler; + /** + * The number of emergency buffers held by this thread. This is 0 in + * normal operation - the emergency buffers are only used when malloc() + * fails to return memory for allocating an exception. Threads are not + * permitted to hold more than 4 emergency buffers (as per recommendation + * in ABI spec [3.3.1]). + */ + int emergencyBuffersHeld; + /** + * The exception currently running in a cleanup. + */ + _Unwind_Exception *currentCleanup; + /** + * Our state with respect to foreign exceptions. Usually none, set to + * caught if we have just caught an exception and rethrown if we are + * rethrowing it. + */ + enum + { + none, + caught, + rethrown + } foreign_exception_state; + /** + * The public part of this structure, accessible from outside of this + * module. + */ + __cxa_eh_globals globals; +}; +/** + * Dependent exception. This + */ +struct __cxa_dependent_exception +{ +#if __LP64__ + void *primaryException; +#endif + std::type_info *exceptionType; + void (*exceptionDestructor) (void *); + unexpected_handler unexpectedHandler; + terminate_handler terminateHandler; + __cxa_exception *nextException; + int handlerCount; +#if defined(__arm__) && !defined(__ARM_DWARF_EH__) + _Unwind_Exception *nextCleanup; + int cleanupCount; +#endif + int handlerSwitchValue; + const char *actionRecord; + const char *languageSpecificData; + void *catchTemp; + void *adjustedPtr; +#if !__LP64__ + void *primaryException; +#endif + _Unwind_Exception unwindHeader; +}; + + +namespace std +{ + void unexpected(); + class exception + { + public: + virtual ~exception() throw(); + virtual const char* what() const throw(); + }; + +} + +/** + * Class of exceptions to distinguish between this and other exception types. + * + * The first four characters are the vendor ID. Currently, we use GNUC, + * because we aim for ABI-compatibility with the GNU implementation, and + * various checks may test for equality of the class, which is incorrect. + */ +static const uint64_t exception_class = + EXCEPTION_CLASS('G', 'N', 'U', 'C', 'C', '+', '+', '\0'); +/** + * Class used for dependent exceptions. + */ +static const uint64_t dependent_exception_class = + EXCEPTION_CLASS('G', 'N', 'U', 'C', 'C', '+', '+', '\x01'); +/** + * The low four bytes of the exception class, indicating that we conform to the + * Itanium C++ ABI. This is currently unused, but should be used in the future + * if we change our exception class, to allow this library and libsupc++ to be + * linked to the same executable and both to interoperate. + */ +static const uint32_t abi_exception_class = + GENERIC_EXCEPTION_CLASS('C', '+', '+', '\0'); + +static bool isCXXException(uint64_t cls) +{ + return (cls == exception_class) || (cls == dependent_exception_class); +} + +static bool isDependentException(uint64_t cls) +{ + return cls == dependent_exception_class; +} + +static __cxa_exception *exceptionFromPointer(void *ex) +{ + return reinterpret_cast<__cxa_exception*>(static_cast<char*>(ex) - + offsetof(struct __cxa_exception, unwindHeader)); +} +static __cxa_exception *realExceptionFromException(__cxa_exception *ex) +{ + if (!isDependentException(ex->unwindHeader.exception_class)) { return ex; } + return reinterpret_cast<__cxa_exception*>((reinterpret_cast<__cxa_dependent_exception*>(ex))->primaryException)-1; +} + + +namespace std +{ + // Forward declaration of standard library terminate() function used to + // abort execution. + void terminate(void); +} + +using namespace ABI_NAMESPACE; + + + +/** The global termination handler. */ +static terminate_handler terminateHandler = abort; +/** The global unexpected exception handler. */ +static unexpected_handler unexpectedHandler = std::terminate; + +/** Key used for thread-local data. */ +static pthread_key_t eh_key; + + +/** + * Cleanup function, allowing foreign exception handlers to correctly destroy + * this exception if they catch it. + */ +static void exception_cleanup(_Unwind_Reason_Code reason, + struct _Unwind_Exception *ex) +{ + __cxa_free_exception(static_cast<void*>(ex)); +} +static void dependent_exception_cleanup(_Unwind_Reason_Code reason, + struct _Unwind_Exception *ex) +{ + + __cxa_free_dependent_exception(static_cast<void*>(ex)); +} + +/** + * Recursively walk a list of exceptions and delete them all in post-order. + */ +static void free_exception_list(__cxa_exception *ex) +{ + if (0 != ex->nextException) + { + free_exception_list(ex->nextException); + } + // __cxa_free_exception() expects to be passed the thrown object, which + // immediately follows the exception, not the exception itself + __cxa_free_exception(ex+1); +} + +/** + * Cleanup function called when a thread exists to make certain that all of the + * per-thread data is deleted. + */ +static void thread_cleanup(void* thread_info) +{ + __cxa_thread_info *info = static_cast<__cxa_thread_info*>(thread_info); + if (info->globals.caughtExceptions) + { + // If this is a foreign exception, ask it to clean itself up. + if (info->foreign_exception_state != __cxa_thread_info::none) + { + _Unwind_Exception *e = reinterpret_cast<_Unwind_Exception*>(info->globals.caughtExceptions); + e->exception_cleanup(_URC_FOREIGN_EXCEPTION_CAUGHT, e); + } + else + { + free_exception_list(info->globals.caughtExceptions); + } + } + free(thread_info); +} + + +/** + * Once control used to protect the key creation. + */ +static pthread_once_t once_control = PTHREAD_ONCE_INIT; + +/** + * We may not be linked against a full pthread implementation. If we're not, + * then we need to fake the thread-local storage by storing 'thread-local' + * things in a global. + */ +static bool fakeTLS; +/** + * Thread-local storage for a single-threaded program. + */ +static __cxa_thread_info singleThreadInfo; +/** + * Initialise eh_key. + */ +static void init_key(void) +{ + if ((0 == pthread_key_create) || + (0 == pthread_setspecific) || + (0 == pthread_getspecific)) + { + fakeTLS = true; + return; + } + pthread_key_create(&eh_key, thread_cleanup); + pthread_setspecific(eh_key, reinterpret_cast<void *>(0x42)); + fakeTLS = (pthread_getspecific(eh_key) != reinterpret_cast<void *>(0x42)); + pthread_setspecific(eh_key, 0); +} + +/** + * Returns the thread info structure, creating it if it is not already created. + */ +static __cxa_thread_info *thread_info() +{ + if ((0 == pthread_once) || pthread_once(&once_control, init_key)) + { + fakeTLS = true; + } + if (fakeTLS) { return &singleThreadInfo; } + __cxa_thread_info *info = static_cast<__cxa_thread_info*>(pthread_getspecific(eh_key)); + if (0 == info) + { + info = static_cast<__cxa_thread_info*>(calloc(1, sizeof(__cxa_thread_info))); + pthread_setspecific(eh_key, info); + } + return info; +} +/** + * Fast version of thread_info(). May fail if thread_info() is not called on + * this thread at least once already. + */ +static __cxa_thread_info *thread_info_fast() +{ + if (fakeTLS) { return &singleThreadInfo; } + return static_cast<__cxa_thread_info*>(pthread_getspecific(eh_key)); +} +/** + * ABI function returning the __cxa_eh_globals structure. + */ +extern "C" __cxa_eh_globals *ABI_NAMESPACE::__cxa_get_globals(void) +{ + return &(thread_info()->globals); +} +/** + * Version of __cxa_get_globals() assuming that __cxa_get_globals() has already + * been called at least once by this thread. + */ +extern "C" __cxa_eh_globals *ABI_NAMESPACE::__cxa_get_globals_fast(void) +{ + return &(thread_info_fast()->globals); +} + +/** + * An emergency allocation reserved for when malloc fails. This is treated as + * 16 buffers of 1KB each. + */ +static char emergency_buffer[16384]; +/** + * Flag indicating whether each buffer is allocated. + */ +static bool buffer_allocated[16]; +/** + * Lock used to protect emergency allocation. + */ +static pthread_mutex_t emergency_malloc_lock = PTHREAD_MUTEX_INITIALIZER; +/** + * Condition variable used to wait when two threads are both trying to use the + * emergency malloc() buffer at once. + */ +static pthread_cond_t emergency_malloc_wait = PTHREAD_COND_INITIALIZER; + +/** + * Allocates size bytes from the emergency allocation mechanism, if possible. + * This function will fail if size is over 1KB or if this thread already has 4 + * emergency buffers. If all emergency buffers are allocated, it will sleep + * until one becomes available. + */ +static char *emergency_malloc(size_t size) +{ + if (size > 1024) { return 0; } + + __cxa_thread_info *info = thread_info(); + // Only 4 emergency buffers allowed per thread! + if (info->emergencyBuffersHeld > 3) { return 0; } + + pthread_mutex_lock(&emergency_malloc_lock); + int buffer = -1; + while (buffer < 0) + { + // While we were sleeping on the lock, another thread might have free'd + // enough memory for us to use, so try the allocation again - no point + // using the emergency buffer if there is some real memory that we can + // use... + void *m = calloc(1, size); + if (0 != m) + { + pthread_mutex_unlock(&emergency_malloc_lock); + return static_cast<char*>(m); + } + for (int i=0 ; i<16 ; i++) + { + if (!buffer_allocated[i]) + { + buffer = i; + buffer_allocated[i] = true; + break; + } + } + // If there still isn't a buffer available, then sleep on the condition + // variable. This will be signalled when another thread releases one + // of the emergency buffers. + if (buffer < 0) + { + pthread_cond_wait(&emergency_malloc_wait, &emergency_malloc_lock); + } + } + pthread_mutex_unlock(&emergency_malloc_lock); + info->emergencyBuffersHeld++; + return emergency_buffer + (1024 * buffer); +} + +/** + * Frees a buffer returned by emergency_malloc(). + * + * Note: Neither this nor emergency_malloc() is particularly efficient. This + * should not matter, because neither will be called in normal operation - they + * are only used when the program runs out of memory, which should not happen + * often. + */ +static void emergency_malloc_free(char *ptr) +{ + int buffer = -1; + // Find the buffer corresponding to this pointer. + for (int i=0 ; i<16 ; i++) + { + if (ptr == static_cast<void*>(emergency_buffer + (1024 * i))) + { + buffer = i; + break; + } + } + assert(buffer >= 0 && + "Trying to free something that is not an emergency buffer!"); + // emergency_malloc() is expected to return 0-initialized data. We don't + // zero the buffer when allocating it, because the static buffers will + // begin life containing 0 values. + memset(ptr, 0, 1024); + // Signal the condition variable to wake up any threads that are blocking + // waiting for some space in the emergency buffer + pthread_mutex_lock(&emergency_malloc_lock); + // In theory, we don't need to do this with the lock held. In practice, + // our array of bools will probably be updated using 32-bit or 64-bit + // memory operations, so this update may clobber adjacent values. + buffer_allocated[buffer] = false; + pthread_cond_signal(&emergency_malloc_wait); + pthread_mutex_unlock(&emergency_malloc_lock); +} + +static char *alloc_or_die(size_t size) +{ + char *buffer = static_cast<char*>(calloc(1, size)); + + // If calloc() doesn't want to give us any memory, try using an emergency + // buffer. + if (0 == buffer) + { + buffer = emergency_malloc(size); + // This is only reached if the allocation is greater than 1KB, and + // anyone throwing objects that big really should know better. + if (0 == buffer) + { + fprintf(stderr, "Out of memory attempting to allocate exception\n"); + std::terminate(); + } + } + return buffer; +} +static void free_exception(char *e) +{ + // If this allocation is within the address range of the emergency buffer, + // don't call free() because it was not allocated with malloc() + if ((e >= emergency_buffer) && + (e < (emergency_buffer + sizeof(emergency_buffer)))) + { + emergency_malloc_free(e); + } + else + { + free(e); + } +} + +/** + * Allocates an exception structure. Returns a pointer to the space that can + * be used to store an object of thrown_size bytes. This function will use an + * emergency buffer if malloc() fails, and may block if there are no such + * buffers available. + */ +extern "C" void *__cxa_allocate_exception(size_t thrown_size) +{ + size_t size = thrown_size + sizeof(__cxa_exception); + char *buffer = alloc_or_die(size); + return buffer+sizeof(__cxa_exception); +} + +extern "C" void *__cxa_allocate_dependent_exception(void) +{ + size_t size = sizeof(__cxa_dependent_exception); + char *buffer = alloc_or_die(size); + return buffer+sizeof(__cxa_dependent_exception); +} + +/** + * __cxa_free_exception() is called when an exception was thrown in between + * calling __cxa_allocate_exception() and actually throwing the exception. + * This happens when the object's copy constructor throws an exception. + * + * In this implementation, it is also called by __cxa_end_catch() and during + * thread cleanup. + */ +extern "C" void __cxa_free_exception(void *thrown_exception) +{ + __cxa_exception *ex = reinterpret_cast<__cxa_exception*>(thrown_exception) - 1; + // Free the object that was thrown, calling its destructor + if (0 != ex->exceptionDestructor) + { + try + { + ex->exceptionDestructor(thrown_exception); + } + catch(...) + { + // FIXME: Check that this is really what the spec says to do. + std::terminate(); + } + } + + free_exception(reinterpret_cast<char*>(ex)); +} + +static void releaseException(__cxa_exception *exception) +{ + if (isDependentException(exception->unwindHeader.exception_class)) + { + __cxa_free_dependent_exception(exception+1); + return; + } + if (__sync_sub_and_fetch(&exception->referenceCount, 1) == 0) + { + // __cxa_free_exception() expects to be passed the thrown object, + // which immediately follows the exception, not the exception + // itself + __cxa_free_exception(exception+1); + } +} + +void __cxa_free_dependent_exception(void *thrown_exception) +{ + __cxa_dependent_exception *ex = reinterpret_cast<__cxa_dependent_exception*>(thrown_exception) - 1; + assert(isDependentException(ex->unwindHeader.exception_class)); + if (ex->primaryException) + { + releaseException(realExceptionFromException(reinterpret_cast<__cxa_exception*>(ex))); + } + free_exception(reinterpret_cast<char*>(ex)); +} + +/** + * Callback function used with _Unwind_Backtrace(). + * + * Prints a stack trace. Used only for debugging help. + * + * Note: As of FreeBSD 8.1, dladd() still doesn't work properly, so this only + * correctly prints function names from public, relocatable, symbols. + */ +static _Unwind_Reason_Code trace(struct _Unwind_Context *context, void *c) +{ + Dl_info myinfo; + int mylookup = + dladdr(reinterpret_cast<void *>(__cxa_current_exception_type), &myinfo); + void *ip = reinterpret_cast<void*>(_Unwind_GetIP(context)); + Dl_info info; + if (dladdr(ip, &info) != 0) + { + if (mylookup == 0 || strcmp(info.dli_fname, myinfo.dli_fname) != 0) + { + printf("%p:%s() in %s\n", ip, info.dli_sname, info.dli_fname); + } + } + return _URC_CONTINUE_UNWIND; +} + +/** + * Report a failure that occurred when attempting to throw an exception. + * + * If the failure happened by falling off the end of the stack without finding + * a handler, prints a back trace before aborting. + */ +#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4) +extern "C" void *__cxa_begin_catch(void *e) throw(); +#else +extern "C" void *__cxa_begin_catch(void *e); +#endif +static void report_failure(_Unwind_Reason_Code err, __cxa_exception *thrown_exception) +{ + switch (err) + { + default: break; + case _URC_FATAL_PHASE1_ERROR: + fprintf(stderr, "Fatal error during phase 1 unwinding\n"); + break; +#if !defined(__arm__) || defined(__ARM_DWARF_EH__) + case _URC_FATAL_PHASE2_ERROR: + fprintf(stderr, "Fatal error during phase 2 unwinding\n"); + break; +#endif + case _URC_END_OF_STACK: + __cxa_begin_catch (&(thrown_exception->unwindHeader)); + std::terminate(); + fprintf(stderr, "Terminating due to uncaught exception %p", + static_cast<void*>(thrown_exception)); + thrown_exception = realExceptionFromException(thrown_exception); + static const __class_type_info *e_ti = + static_cast<const __class_type_info*>(&typeid(std::exception)); + const __class_type_info *throw_ti = + dynamic_cast<const __class_type_info*>(thrown_exception->exceptionType); + if (throw_ti) + { + std::exception *e = + static_cast<std::exception*>(e_ti->cast_to(static_cast<void*>(thrown_exception+1), + throw_ti)); + if (e) + { + fprintf(stderr, " '%s'", e->what()); + } + } + + size_t bufferSize = 128; + char *demangled = static_cast<char*>(malloc(bufferSize)); + const char *mangled = thrown_exception->exceptionType->name(); + int status; + demangled = __cxa_demangle(mangled, demangled, &bufferSize, &status); + fprintf(stderr, " of type %s\n", + status == 0 ? demangled : mangled); + if (status == 0) { free(demangled); } + // Print a back trace if no handler is found. + // TODO: Make this optional +#ifndef __arm__ + _Unwind_Backtrace(trace, 0); +#endif + + // Just abort. No need to call std::terminate for the second time + abort(); + break; + } + std::terminate(); +} + +static void throw_exception(__cxa_exception *ex) +{ + __cxa_thread_info *info = thread_info(); + ex->unexpectedHandler = info->unexpectedHandler; + if (0 == ex->unexpectedHandler) + { + ex->unexpectedHandler = unexpectedHandler; + } + ex->terminateHandler = info->terminateHandler; + if (0 == ex->terminateHandler) + { + ex->terminateHandler = terminateHandler; + } + info->globals.uncaughtExceptions++; + + _Unwind_Reason_Code err = _Unwind_RaiseException(&ex->unwindHeader); + // The _Unwind_RaiseException() function should not return, it should + // unwind the stack past this function. If it does return, then something + // has gone wrong. + report_failure(err, ex); +} + + +/** + * ABI function for throwing an exception. Takes the object to be thrown (the + * pointer returned by __cxa_allocate_exception()), the type info for the + * pointee, and the destructor (if there is one) as arguments. + */ +extern "C" void __cxa_throw(void *thrown_exception, + std::type_info *tinfo, + void(*dest)(void*)) +{ + __cxa_exception *ex = reinterpret_cast<__cxa_exception*>(thrown_exception) - 1; + + ex->referenceCount = 1; + ex->exceptionType = tinfo; + + ex->exceptionDestructor = dest; + + ex->unwindHeader.exception_class = exception_class; + ex->unwindHeader.exception_cleanup = exception_cleanup; + + throw_exception(ex); +} + +extern "C" void __cxa_rethrow_primary_exception(void* thrown_exception) +{ + if (NULL == thrown_exception) { return; } + + __cxa_exception *original = exceptionFromPointer(thrown_exception); + __cxa_dependent_exception *ex = reinterpret_cast<__cxa_dependent_exception*>(__cxa_allocate_dependent_exception())-1; + + ex->primaryException = thrown_exception; + __cxa_increment_exception_refcount(thrown_exception); + + ex->exceptionType = original->exceptionType; + ex->unwindHeader.exception_class = dependent_exception_class; + ex->unwindHeader.exception_cleanup = dependent_exception_cleanup; + + throw_exception(reinterpret_cast<__cxa_exception*>(ex)); +} + +extern "C" void *__cxa_current_primary_exception(void) +{ + __cxa_eh_globals* globals = __cxa_get_globals(); + __cxa_exception *ex = globals->caughtExceptions; + + if (0 == ex) { return NULL; } + ex = realExceptionFromException(ex); + __sync_fetch_and_add(&ex->referenceCount, 1); + return ex + 1; +} + +extern "C" void __cxa_increment_exception_refcount(void* thrown_exception) +{ + if (NULL == thrown_exception) { return; } + __cxa_exception *ex = static_cast<__cxa_exception*>(thrown_exception) - 1; + if (isDependentException(ex->unwindHeader.exception_class)) { return; } + __sync_fetch_and_add(&ex->referenceCount, 1); +} +extern "C" void __cxa_decrement_exception_refcount(void* thrown_exception) +{ + if (NULL == thrown_exception) { return; } + __cxa_exception *ex = static_cast<__cxa_exception*>(thrown_exception) - 1; + releaseException(ex); +} + +/** + * ABI function. Rethrows the current exception. Does not remove the + * exception from the stack or decrement its handler count - the compiler is + * expected to set the landing pad for this function to the end of the catch + * block, and then call _Unwind_Resume() to continue unwinding once + * __cxa_end_catch() has been called and any cleanup code has been run. + */ +extern "C" void __cxa_rethrow() +{ + __cxa_thread_info *ti = thread_info(); + __cxa_eh_globals *globals = &ti->globals; + // Note: We don't remove this from the caught list here, because + // __cxa_end_catch will be called when we unwind out of the try block. We + // could probably make this faster by providing an alternative rethrow + // function and ensuring that all cleanup code is run before calling it, so + // we can skip the top stack frame when unwinding. + __cxa_exception *ex = globals->caughtExceptions; + + if (0 == ex) + { + fprintf(stderr, + "Attempting to rethrow an exception that doesn't exist!\n"); + std::terminate(); + } + + if (ti->foreign_exception_state != __cxa_thread_info::none) + { + ti->foreign_exception_state = __cxa_thread_info::rethrown; + _Unwind_Exception *e = reinterpret_cast<_Unwind_Exception*>(ex); + _Unwind_Reason_Code err = _Unwind_Resume_or_Rethrow(e); + report_failure(err, ex); + return; + } + + assert(ex->handlerCount > 0 && "Rethrowing uncaught exception!"); + + // ex->handlerCount will be decremented in __cxa_end_catch in enclosing + // catch block + + // Make handler count negative. This will tell __cxa_end_catch that + // exception was rethrown and exception object should not be destroyed + // when handler count become zero + ex->handlerCount = -ex->handlerCount; + + // Continue unwinding the stack with this exception. This should unwind to + // the place in the caller where __cxa_end_catch() is called. The caller + // will then run cleanup code and bounce the exception back with + // _Unwind_Resume(). + _Unwind_Reason_Code err = _Unwind_Resume_or_Rethrow(&ex->unwindHeader); + report_failure(err, ex); +} + +/** + * Returns the type_info object corresponding to the filter. + */ +static std::type_info *get_type_info_entry(_Unwind_Context *context, + dwarf_eh_lsda *lsda, + int filter) +{ + // Get the address of the record in the table. + dw_eh_ptr_t record = lsda->type_table - + dwarf_size_of_fixed_size_field(lsda->type_table_encoding)*filter; + //record -= 4; + dw_eh_ptr_t start = record; + // Read the value, but it's probably an indirect reference... + int64_t offset = read_value(lsda->type_table_encoding, &record); + + // (If the entry is 0, don't try to dereference it. That would be bad.) + if (offset == 0) { return 0; } + + // ...so we need to resolve it + return reinterpret_cast<std::type_info*>(resolve_indirect_value(context, + lsda->type_table_encoding, offset, start)); +} + + + +/** + * Checks the type signature found in a handler against the type of the thrown + * object. If ex is 0 then it is assumed to be a foreign exception and only + * matches cleanups. + */ +static bool check_type_signature(__cxa_exception *ex, + const std::type_info *type, + void *&adjustedPtr) +{ + void *exception_ptr = static_cast<void*>(ex+1); + const std::type_info *ex_type = ex ? ex->exceptionType : 0; + + bool is_ptr = ex ? ex_type->__is_pointer_p() : false; + if (is_ptr) + { + exception_ptr = *static_cast<void**>(exception_ptr); + } + // Always match a catchall, even with a foreign exception + // + // Note: A 0 here is a catchall, not a cleanup, so we return true to + // indicate that we found a catch. + if (0 == type) + { + if (ex) + { + adjustedPtr = exception_ptr; + } + return true; + } + + if (0 == ex) { return false; } + + // If the types are the same, no casting is needed. + if (*type == *ex_type) + { + adjustedPtr = exception_ptr; + return true; + } + + + if (type->__do_catch(ex_type, &exception_ptr, 1)) + { + adjustedPtr = exception_ptr; + return true; + } + + return false; +} +/** + * Checks whether the exception matches the type specifiers in this action + * record. If the exception only matches cleanups, then this returns false. + * If it matches a catch (including a catchall) then it returns true. + * + * The selector argument is used to return the selector that is passed in the + * second exception register when installing the context. + */ +static handler_type check_action_record(_Unwind_Context *context, + dwarf_eh_lsda *lsda, + dw_eh_ptr_t action_record, + __cxa_exception *ex, + unsigned long *selector, + void *&adjustedPtr) +{ + if (!action_record) { return handler_cleanup; } + handler_type found = handler_none; + while (action_record) + { + int filter = read_sleb128(&action_record); + dw_eh_ptr_t action_record_offset_base = action_record; + int displacement = read_sleb128(&action_record); + action_record = displacement ? + action_record_offset_base + displacement : 0; + // We only check handler types for C++ exceptions - foreign exceptions + // are only allowed for cleanups and catchalls. + if (filter > 0) + { + std::type_info *handler_type = get_type_info_entry(context, lsda, filter); + if (check_type_signature(ex, handler_type, adjustedPtr)) + { + *selector = filter; + return handler_catch; + } + } + else if (filter < 0 && 0 != ex) + { + bool matched = false; + *selector = filter; +#if defined(__arm__) && !defined(__ARM_DWARF_EH__) + filter++; *** DIFF OUTPUT TRUNCATED AT 1000 LINES ***
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