static inline NORETURN void resume(unw_cursor_t* cursor, const uint8_t* landing_pad, int64_t switch_value,
const ExcInfo* exc_data) {
checkExcInfo(exc_data);
assert(landing_pad);
if (VERBOSITY("cxx_unwind") >= 4)
printf(" * RESUMED: ip %p switch_value %ld\n", (const void*)landing_pad, (long)switch_value);
if (0 != switch_value) {
// The exception handler will call __cxa_begin_catch, which stops this timer and logs it.
per_thread_resume_catch_timer.restart("resume_catch", 20);
} else {
// The cleanup code will call _Unwind_Resume, which will stop this timer and log it.
// TODO: am I sure cleanup code can't raise exceptions? maybe have an assert!
per_thread_cleanup_timer.restart("cleanup", 20);
#ifndef NDEBUG
in_cleanup_code = true;
#endif
}
// set rax to pointer to exception object
// set rdx to the switch_value (0 for cleanup, otherwise an index indicating which exception handler to use)
//
// NB. assumes x86-64. maybe I should use __builtin_eh_return_data_regno() here?
// but then, need to translate into UNW_* values somehow. not clear how.
check(unw_set_reg(cursor, UNW_X86_64_RAX, (unw_word_t)exc_data));
check(unw_set_reg(cursor, UNW_X86_64_RDX, switch_value));
// resume!
check(unw_set_reg(cursor, UNW_REG_IP, (unw_word_t)landing_pad));
unw_resume(cursor);
RELEASE_ASSERT(0, "unw_resume returned!");
}
void
jffi_longjmp (jmp_buf env, int val)
{
extern int _jffi_longjmp_cont;
unw_context_t uc;
unw_cursor_t c;
unw_word_t sp, ip, bp = 0;
uintptr_t *wp = (uintptr_t *) env;
int i, setjmp_frame;
if (unw_getcontext (&uc) < 0 || unw_init_local (&c, &uc) < 0) {
debug("failed to get context");
abort ();
}
#ifdef __x86_86__
# define UNW_REG_BP UNW_X86_64_RBP
#else
# define UNW_REG_BP UNW_X86_EBP
#endif
setjmp_frame = 0;
do {
char name[256];
unw_proc_info_t pi;
unw_word_t off;
if (unw_get_reg (&c, UNW_REG_BP, &bp) < 0) {
abort();
}
if (unw_get_reg (&c, UNW_REG_SP, &sp) < 0) {
abort();
}
if (unw_get_reg (&c, UNW_REG_IP, &ip) < 0) {
abort();
}
unw_get_proc_name(&c, name, sizeof(name), &off);
unw_get_proc_info(&c, &pi);
// debug("frame %s ip=%llx sp=%llx bp=%llx wp[RP]=%p wp[SP]=%p, pi.start_ip=%llx, pi.end_ip=%llx",
// name, (long long) ip, (long long) sp, (long long) bp, (void *) wp[JB_RP], (void *) wp[JB_SP],
// pi.start_ip, pi.end_ip);
if (wp[JB_SP] > sp || wp[JB_RP] < pi.start_ip || wp[JB_RP] > pi.end_ip) continue;
/* found the right frame: */
// debug("found frame to jump back to");
assert (UNW_NUM_EH_REGS >= 2);
if (unw_set_reg (&c, UNW_REG_EH + 0, wp[JB_RP]) < 0
|| unw_set_reg (&c, UNW_REG_EH + 1, val) < 0
|| unw_set_reg (&c, UNW_REG_IP, (unw_word_t) (uintptr_t) &_jffi_longjmp_cont))
abort ();
unw_resume (&c);
// should not reach here
abort ();
} while (unw_step (&c) > 0);
// debug("failed to find correct frame to jmp to");
}
static void
restore_context (MonoContext *ctx)
{
int res;
unw_word_t ip;
res = unw_get_reg (&ctx->cursor, UNW_IA64_IP, &ip);
g_assert (res == 0);
/* Set this to 0 to tell OP_START_HANDLER that it doesn't have to set the frame pointer */
res = unw_set_reg (&ctx->cursor, UNW_IA64_GR + 15, 0);
g_assert (res == 0);
unw_resume (&ctx->cursor);
}
void
_longjmp (jmp_buf env, int val)
{
extern int _UI_longjmp_cont;
unw_context_t uc;
unw_cursor_t c;
unw_word_t sp;
unw_word_t *wp = (unw_word_t *) env;
if (unw_getcontext (&uc) < 0 || unw_init_local (&c, &uc) < 0)
abort ();
do
{
if (unw_get_reg (&c, UNW_REG_SP, &sp) < 0)
abort ();
#ifdef __FreeBSD__
if (sp != wp[JB_SP] + sizeof(unw_word_t))
#else
if (sp != wp[JB_SP])
#endif
continue;
if (!bsp_match (&c, wp))
continue;
/* found the right frame: */
assert (UNW_NUM_EH_REGS >= 2);
if (unw_set_reg (&c, UNW_REG_EH + 0, wp[JB_RP]) < 0
|| unw_set_reg (&c, UNW_REG_EH + 1, val) < 0
|| unw_set_reg (&c, UNW_REG_IP,
(unw_word_t) (uintptr_t) &_UI_longjmp_cont))
abort ();
unw_resume (&c);
abort ();
}
while (unw_step (&c) > 0);
abort ();
}
static void
sighandler (int signal)
{
unw_cursor_t cursor, cursor2;
unw_word_t ip;
unw_context_t uc;
if (verbose)
printf ("caught signal %d\n", signal);
unw_getcontext (&uc);
if (unw_init_local (&cursor, &uc) < 0)
panic ("unw_init() failed!\n");
/* get cursor for caller of sighandler: */
if (unw_step (&cursor) < 0)
panic ("unw_step() failed!\n");
cursor2 = cursor;
while (!unw_is_signal_frame (&cursor2))
if (unw_step (&cursor2) < 0)
panic ("failed to find signal frame!\n");
if (unw_step (&cursor2) < 0)
panic ("unw_step() failed!\n");
if (unw_get_reg (&cursor2, UNW_REG_IP, &ip) < 0)
panic ("failed to get IP!\n");
/* skip faulting instruction (doesn't handle MLX template) */
++ip;
if ((ip & 0x3) == 0x3)
ip += 13;
if (unw_set_reg (&cursor2, UNW_REG_IP, ip) < 0)
panic ("failed to set IP!\n");
unw_resume (&cursor); /* update context & return to caller of sighandler() */
panic ("unexpected return from unw_resume()!\n");
}
// called by test function
// we unwind through the test function
// and resume at caller (unwind_tester)
void uwind_to_main () {
/* Invoke our handler with our current thread state; we use this state to try to roll back the tests
* and verify that the expected registers are restored. */
if (plcrash_async_thread_state_current(unwind_current_state, NULL) != PLCRASH_ESUCCESS) {
__builtin_trap();
}
/* Now use libunwind to verify that our test data can be unwound sucessfully. This will unwind the current
* thread to the unwind_tester, and we'll never return from this function */
#ifdef LIBUNWIND_VERIFICATION
if (global_harness_state.test_case->skip_libunwind_verification)
return;
unw_cursor_t cursor;
unw_context_t uc;
unw_getcontext(&uc);
unw_init_local(&cursor, &uc);
/* Walk the frames until we hit the test function. Unlike our unwinder, the first frame is implicitly
* available -- a step isn't required, and so we skip one call to unw_step(). */
for (uint32_t i = 1; i < global_harness_state.test_case->intermediate_frames; i++) {
int ret;
if ((ret = unw_step(&cursor)) <= 0) {
PLCF_DEBUG("Step %" PRIu32 " failed: %d", i, ret);
__builtin_trap();
}
}
/* Once inside the test implementation, resume */
if (unw_step(&cursor) > 0) {
unw_resume(&cursor);
}
/* This should be unreachable */
__builtin_trap();
#endif
}
static int
unwind_and_resume (long iteration, int (*next_func[])())
{
unw_context_t uc;
unw_cursor_t c;
unw_word_t ip;
int i, ret;
if (verbose)
printf (" %s(iteration=%ld, next_func=%p)\n",
__FUNCTION__, iteration, next_func);
unw_getcontext (&uc);
if ((ret = unw_init_local (&c, &uc)) < 0)
panic ("unw_init_local (ret=%d)", ret);
for (i = 0; i < unwind_count; ++i)
if ((ret = unw_step (&c)) < 0)
panic ("unw_step (ret=%d)", ret);
if (unw_get_reg (&c, UNW_REG_IP, &ip) < 0
|| unw_set_reg (&c, UNW_REG_IP, (unw_word_t) &resumption_point_label) < 0
|| unw_set_reg (&c, UNW_REG_EH + 0, 0) /* ret val */
|| unw_set_reg (&c, UNW_REG_EH + 1, ip))
panic ("failed to redirect to resumption_point\n");
if (verbose)
{
unw_word_t bsp;
if (unw_get_reg (&c, UNW_IA64_BSP, &bsp) < 0)
panic ("unw_get_reg() failed\n");
printf (" bsp=%lx, old ip=%lx, new ip=%p\n", bsp,
ip, &resumption_point_label);
}
ret = unw_resume (&c);
panic ("unw_resume() returned (ret=%d)!!\n", ret);
return 0;
}
void
siglongjmp (sigjmp_buf env, int val)
{
unw_word_t *wp = (unw_word_t *) env;
extern int _UI_siglongjmp_cont;
extern int _UI_longjmp_cont;
unw_context_t uc;
unw_cursor_t c;
unw_word_t sp;
int *cont;
if (unw_getcontext (&uc) < 0 || unw_init_local (&c, &uc) < 0)
abort ();
do
{
if (unw_get_reg (&c, UNW_REG_SP, &sp) < 0)
abort ();
#ifdef __FreeBSD__
if (sp != wp[JB_SP] + sizeof(unw_word_t))
#else
if (sp != wp[JB_SP])
#endif
continue;
if (!bsp_match (&c, wp))
continue;
/* found the right frame: */
/* default to resuming without restoring signal-mask */
cont = &_UI_longjmp_cont;
/* Order of evaluation is important here: if unw_resume()
restores signal mask, we must set it up appropriately, even
if wp[JB_MASK_SAVED] is FALSE. */
if (!resume_restores_sigmask (&c, wp) && wp[JB_MASK_SAVED])
{
/* sigmask was saved */
if (UNW_NUM_EH_REGS < 4 || _NSIG >= 16 * sizeof (unw_word_t))
/* signal mask doesn't fit into EH arguments and we can't
put it on the stack without overwriting something
else... */
abort ();
else
if (unw_set_reg (&c, UNW_REG_EH + 2, wp[JB_MASK]) < 0
|| (_NSIG > 8 * sizeof (unw_word_t)
&& unw_set_reg (&c, UNW_REG_EH + 3, wp[JB_MASK + 1]) < 0))
abort ();
cont = &_UI_siglongjmp_cont;
}
if (unw_set_reg (&c, UNW_REG_EH + 0, wp[JB_RP]) < 0
|| unw_set_reg (&c, UNW_REG_EH + 1, val) < 0
|| unw_set_reg (&c, UNW_REG_IP, (unw_word_t) (uintptr_t) cont))
abort ();
unw_resume (&c);
abort ();
}
while (unw_step (&c) > 0);
abort ();
}
void
handler (int sig)
#endif
{
unw_word_t ip;
sigset_t mask, oldmask;
unw_context_t uc;
unw_cursor_t c;
char foo;
int ret;
#if UNW_TARGET_IA64
if (verbose)
printf ("bsp = %llx\n", (unsigned long long) get_bsp ());
#endif
if (verbose)
printf ("got signal %d\n", sig);
if (sig == SIGUSR1)
{
++got_usr1;
sigusr1_sp = &foo;
sigemptyset (&mask);
sigaddset (&mask, SIGUSR2);
sigprocmask (SIG_BLOCK, &mask, &oldmask);
kill (getpid (), SIGUSR2); /* pend SIGUSR2 */
signal (SIGUSR1, SIG_IGN);
if ((ret = unw_getcontext (&uc)) < 0)
panic ("unw_getcontext() failed: ret=%d\n", ret);
#if UNW_TARGET_X86_64
/* unw_getcontext() doesn't save signal mask to avoid a syscall */
uc.uc_sigmask = oldmask;
#endif
if ((ret = unw_init_local (&c, &uc)) < 0)
panic ("unw_init_local() failed: ret=%d\n", ret);
if ((ret = unw_step (&c)) < 0) /* step to signal trampoline */
panic ("unw_step(1) failed: ret=%d\n", ret);
if ((ret = unw_step (&c)) < 0) /* step to kill() */
panic ("unw_step(2) failed: ret=%d\n", ret);
if ((ret = unw_get_reg (&c, UNW_REG_IP, &ip)) < 0)
panic ("unw_get_reg(IP) failed: ret=%d\n", ret);
if (verbose)
printf ("resuming at 0x%lx, with SIGUSR2 pending\n",
(unsigned long) ip);
unw_resume (&c);
}
else if (sig == SIGUSR2)
{
++got_usr2;
if (got_usr1)
{
if (verbose)
printf ("OK: stack still at %p\n", &foo);
}
signal (SIGUSR2, SIG_IGN);
}
else
panic ("Got unexpected signal %d\n", sig);
}
static _Unwind_Reason_Code
unwind_phase2(unw_context_t *uc, struct _Unwind_Exception *exception_object, bool resume) {
// See comment at the start of unwind_phase1 regarding VRS integrity.
unw_cursor_t cursor2;
unw_init_local(&cursor2, uc);
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p)\n", exception_object);
int frame_count = 0;
// Walk each frame until we reach where search phase said to stop.
while (true) {
// Ask libuwind to get next frame (skip over first which is
// _Unwind_RaiseException or _Unwind_Resume).
//
// Resume only ever makes sense for 1 frame.
_Unwind_State state =
resume ? _US_UNWIND_FRAME_RESUME : _US_UNWIND_FRAME_STARTING;
if (resume && frame_count == 1) {
// On a resume, first unwind the _Unwind_Resume() frame. The next frame
// is now the landing pad for the cleanup from a previous execution of
// phase2. To continue unwindingly correctly, replace VRS[15] with the
// IP of the frame that the previous run of phase2 installed the context
// for. After this, continue unwinding as if normal.
//
// See #7.4.6 for details.
unw_set_reg(&cursor2, UNW_REG_IP, exception_object->unwinder_cache.reserved2);
resume = false;
}
int stepResult = unw_step(&cursor2);
if (stepResult == 0) {
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step() reached "
"bottom => _URC_END_OF_STACK\n",
exception_object);
return _URC_END_OF_STACK;
} else if (stepResult < 0) {
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step failed => "
"_URC_FATAL_PHASE1_ERROR\n",
exception_object);
return _URC_FATAL_PHASE2_ERROR;
}
// Get info about this frame.
unw_word_t sp;
unw_proc_info_t frameInfo;
unw_get_reg(&cursor2, UNW_REG_SP, &sp);
if (unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_get_proc_info "
"failed => _URC_FATAL_PHASE1_ERROR\n",
exception_object);
return _URC_FATAL_PHASE2_ERROR;
}
// When tracing, print state information.
if (_LIBUNWIND_TRACING_UNWINDING) {
char functionName[512];
unw_word_t offset;
if ((unw_get_proc_name(&cursor2, functionName, 512, &offset) !=
UNW_ESUCCESS) || (frameInfo.start_ip + offset > frameInfo.end_ip))
strcpy(functionName, ".anonymous.");
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2(ex_ojb=%p): start_ip=0x%llX, func=%s, sp=0x%llX, "
"lsda=0x%llX, personality=0x%llX\n",
exception_object, frameInfo.start_ip, functionName, sp,
frameInfo.lsda, frameInfo.handler);
}
// If there is a personality routine, tell it we are unwinding.
if (frameInfo.handler != 0) {
__personality_routine p =
(__personality_routine)(long)(frameInfo.handler);
struct _Unwind_Context *context = (struct _Unwind_Context *)(&cursor2);
#ifdef __arm__
exception_object->pr_cache.fnstart = frameInfo.start_ip;
exception_object->pr_cache.ehtp = (_Unwind_EHT_Header *)frameInfo.unwind_info;
exception_object->pr_cache.additional = frameInfo.flags;
_Unwind_Reason_Code personalityResult =
(*p)(state, exception_object, context);
#else
_Unwind_Action action = _UA_CLEANUP_PHASE;
if (sp == exception_object->private_2) {
// Tell personality this was the frame it marked in phase 1.
action = (_Unwind_Action)(_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME);
}
_Unwind_Reason_Code personalityResult =
(*p)(1, action, exception_object->exception_class, exception_object,
context);
#endif
switch (personalityResult) {
case _URC_CONTINUE_UNWIND:
// Continue unwinding
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2(ex_ojb=%p): _URC_CONTINUE_UNWIND\n",
exception_object);
#ifdef __arm__
if (sp == exception_object->barrier_cache.sp) {
#else
if (sp == exception_object->private_2) {
#endif
// Phase 1 said we would stop at this frame, but we did not...
_LIBUNWIND_ABORT("during phase1 personality function said it would "
"stop here, but now in phase2 it did not stop here");
}
break;
case _URC_INSTALL_CONTEXT:
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2(ex_ojb=%p): _URC_INSTALL_CONTEXT\n",
exception_object);
// Personality routine says to transfer control to landing pad.
// We may get control back if landing pad calls _Unwind_Resume().
if (_LIBUNWIND_TRACING_UNWINDING) {
unw_word_t pc;
unw_get_reg(&cursor2, UNW_REG_IP, &pc);
unw_get_reg(&cursor2, UNW_REG_SP, &sp);
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): re-entering "
"user code with ip=0x%llX, sp=0x%llX\n",
exception_object, pc, sp);
}
#ifdef __arm__
// #7.4.1 says we need to preserve pc for when _Unwind_Resume is called
// back, to find this same frame.
unw_word_t pc;
unw_get_reg(&cursor2, UNW_REG_IP, &pc);
exception_object->unwinder_cache.reserved2 = (uint32_t)pc;
#endif
unw_resume(&cursor2);
// unw_resume() only returns if there was an error.
return _URC_FATAL_PHASE2_ERROR;
#ifdef __arm__
// # 7.4.3
case _URC_FAILURE:
abort();
#endif
default:
// Personality routine returned an unknown result code.
_LIBUNWIND_DEBUG_LOG("personality function returned unknown result %d",
personalityResult);
return _URC_FATAL_PHASE2_ERROR;
}
}
frame_count++;
}
// Clean up phase did not resume at the frame that the search phase
// said it would...
return _URC_FATAL_PHASE2_ERROR;
}
#ifndef __arm__
static _Unwind_Reason_Code
unwind_phase2_forced(unw_context_t *uc,
struct _Unwind_Exception *exception_object,
_Unwind_Stop_Fn stop, void *stop_parameter) {
unw_cursor_t cursor2;
unw_init_local(&cursor2, uc);
// Walk each frame until we reach where search phase said to stop
while (unw_step(&cursor2) > 0) {
// Update info about this frame.
unw_proc_info_t frameInfo;
if (unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): unw_step "
"failed => _URC_END_OF_STACK\n",
exception_object);
return _URC_FATAL_PHASE2_ERROR;
}
// When tracing, print state information.
if (_LIBUNWIND_TRACING_UNWINDING) {
char functionName[512];
unw_word_t offset;
if ((unw_get_proc_name(&cursor2, functionName, 512, &offset) !=
UNW_ESUCCESS) || (frameInfo.start_ip + offset > frameInfo.end_ip))
strcpy(functionName, ".anonymous.");
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
"start_ip=0x%llX, func=%s, lsda=0x%llX, "
" personality=0x%llX\n",
exception_object, frameInfo.start_ip,
functionName, frameInfo.lsda,
frameInfo.handler);
}
// Call stop function at each frame.
_Unwind_Action action =
(_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE);
_Unwind_Reason_Code stopResult =
(*stop)(1, action, exception_object->exception_class, exception_object,
(struct _Unwind_Context *)(&cursor2), stop_parameter);
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2_forced(ex_ojb=%p): stop function returned %d\n",
exception_object, stopResult);
if (stopResult != _URC_NO_REASON) {
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2_forced(ex_ojb=%p): stopped by stop function\n",
exception_object);
return _URC_FATAL_PHASE2_ERROR;
}
// If there is a personality routine, tell it we are unwinding.
if (frameInfo.handler != 0) {
__personality_routine p =
(__personality_routine)(long)(frameInfo.handler);
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2_forced(ex_ojb=%p): calling personality function %p\n",
exception_object, p);
_Unwind_Reason_Code personalityResult =
(*p)(1, action, exception_object->exception_class, exception_object,
(struct _Unwind_Context *)(&cursor2));
switch (personalityResult) {
case _URC_CONTINUE_UNWIND:
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
"personality returned _URC_CONTINUE_UNWIND\n",
exception_object);
// Destructors called, continue unwinding
break;
case _URC_INSTALL_CONTEXT:
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
"personality returned _URC_INSTALL_CONTEXT\n",
exception_object);
// We may get control back if landing pad calls _Unwind_Resume().
unw_resume(&cursor2);
break;
default:
// Personality routine returned an unknown result code.
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
"personality returned %d, "
"_URC_FATAL_PHASE2_ERROR\n",
exception_object, personalityResult);
return _URC_FATAL_PHASE2_ERROR;
}
}
}
// Call stop function one last time and tell it we've reached the end
// of the stack.
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): calling stop "
"function with _UA_END_OF_STACK\n",
exception_object);
_Unwind_Action lastAction =
(_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE | _UA_END_OF_STACK);
(*stop)(1, lastAction, exception_object->exception_class, exception_object,
(struct _Unwind_Context *)(&cursor2), stop_parameter);
// Clean up phase did not resume at the frame that the search phase said it
// would.
return _URC_FATAL_PHASE2_ERROR;
}
static _Unwind_Reason_Code
unwind_phase2_forced(unw_context_t *uc,
_Unwind_Exception *exception_object,
_Unwind_Stop_Fn stop, void *stop_parameter) {
unw_cursor_t cursor2;
unw_init_local(&cursor2, uc);
// Walk each frame until we reach where search phase said to stop
while (unw_step(&cursor2) > 0) {
// Update info about this frame.
unw_proc_info_t frameInfo;
if (unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): unw_step "
"failed => _URC_END_OF_STACK\n",
exception_object);
return _URC_FATAL_PHASE2_ERROR;
}
// When tracing, print state information.
if (_LIBUNWIND_TRACING_UNWINDING) {
char functionName[512];
unw_word_t offset;
if ((unw_get_proc_name(&cursor2, functionName, 512, &offset) !=
UNW_ESUCCESS) || (frameInfo.start_ip + offset > frameInfo.end_ip))
strcpy(functionName, ".anonymous.");
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
"start_ip=0x%llX, func=%s, lsda=0x%llX, "
" personality=0x%llX\n",
exception_object, frameInfo.start_ip,
functionName, frameInfo.lsda,
frameInfo.handler);
}
// Call stop function at each frame.
_Unwind_Action action =
(_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE);
_Unwind_Reason_Code stopResult =
(*stop)(1, action, exception_object->exception_class, exception_object,
(struct _Unwind_Context *)(&cursor2), stop_parameter);
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2_forced(ex_ojb=%p): stop function returned %d\n",
exception_object, stopResult);
if (stopResult != _URC_NO_REASON) {
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2_forced(ex_ojb=%p): stopped by stop function\n",
exception_object);
return _URC_FATAL_PHASE2_ERROR;
}
// If there is a personality routine, tell it we are unwinding.
if (frameInfo.handler != 0) {
__personality_routine p =
(__personality_routine)(long)(frameInfo.handler);
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2_forced(ex_ojb=%p): calling personality function %p\n",
exception_object, p);
_Unwind_Reason_Code personalityResult =
(*p)(1, action, exception_object->exception_class, exception_object,
(struct _Unwind_Context *)(&cursor2));
switch (personalityResult) {
case _URC_CONTINUE_UNWIND:
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
"personality returned _URC_CONTINUE_UNWIND\n",
exception_object);
// Destructors called, continue unwinding
break;
case _URC_INSTALL_CONTEXT:
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
"personality returned _URC_INSTALL_CONTEXT\n",
exception_object);
// We may get control back if landing pad calls _Unwind_Resume().
unw_resume(&cursor2);
break;
default:
// Personality routine returned an unknown result code.
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
"personality returned %d, "
"_URC_FATAL_PHASE2_ERROR\n",
exception_object, personalityResult);
return _URC_FATAL_PHASE2_ERROR;
}
}
}
// Call stop function one last time and tell it we've reached the end
// of the stack.
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): calling stop "
"function with _UA_END_OF_STACK\n",
exception_object);
_Unwind_Action lastAction =
(_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE | _UA_END_OF_STACK);
(*stop)(1, lastAction, exception_object->exception_class, exception_object,
(struct _Unwind_Context *)(&cursor2), stop_parameter);
// Clean up phase did not resume at the frame that the search phase said it
// would.
return _URC_FATAL_PHASE2_ERROR;
}
static _Unwind_Reason_Code
unwind_phase2(unw_context_t *uc, _Unwind_Exception *exception_object) {
unw_cursor_t cursor2;
unw_init_local(&cursor2, uc);
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p)\n", exception_object);
// Walk each frame until we reach where search phase said to stop.
while (true) {
// Ask libuwind to get next frame (skip over first which is
// _Unwind_RaiseException).
int stepResult = unw_step(&cursor2);
if (stepResult == 0) {
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step() reached "
"bottom => _URC_END_OF_STACK\n",
exception_object);
return _URC_END_OF_STACK;
} else if (stepResult < 0) {
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step failed => "
"_URC_FATAL_PHASE1_ERROR\n",
exception_object);
return _URC_FATAL_PHASE2_ERROR;
}
// Get info about this frame.
unw_word_t sp;
unw_proc_info_t frameInfo;
unw_get_reg(&cursor2, UNW_REG_SP, &sp);
if (unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_get_proc_info "
"failed => _URC_FATAL_PHASE1_ERROR\n",
exception_object);
return _URC_FATAL_PHASE2_ERROR;
}
// When tracing, print state information.
if (_LIBUNWIND_TRACING_UNWINDING) {
char functionName[512];
unw_word_t offset;
if ((unw_get_proc_name(&cursor2, functionName, 512, &offset) !=
UNW_ESUCCESS) || (frameInfo.start_ip + offset > frameInfo.end_ip))
strcpy(functionName, ".anonymous.");
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2(ex_ojb=%p): start_ip=0x%llX, func=%s, sp=0x%llX, "
"lsda=0x%llX, personality=0x%llX\n",
exception_object, frameInfo.start_ip, functionName, sp,
frameInfo.lsda, frameInfo.handler);
}
// If there is a personality routine, tell it we are unwinding.
if (frameInfo.handler != 0) {
__personality_routine p =
(__personality_routine)(long)(frameInfo.handler);
_Unwind_Action action = _UA_CLEANUP_PHASE;
if (sp == exception_object->private_2) {
// Tell personality this was the frame it marked in phase 1.
action = (_Unwind_Action)(_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME);
}
_Unwind_Reason_Code personalityResult =
(*p)(1, action, exception_object->exception_class, exception_object,
(struct _Unwind_Context *)(&cursor2));
switch (personalityResult) {
case _URC_CONTINUE_UNWIND:
// Continue unwinding
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2(ex_ojb=%p): _URC_CONTINUE_UNWIND\n",
exception_object);
if (sp == exception_object->private_2) {
// Phase 1 said we would stop at this frame, but we did not...
_LIBUNWIND_ABORT("during phase1 personality function said it would "
"stop here, but now in phase2 it did not stop here");
}
break;
case _URC_INSTALL_CONTEXT:
_LIBUNWIND_TRACE_UNWINDING(
"unwind_phase2(ex_ojb=%p): _URC_INSTALL_CONTEXT\n",
exception_object);
// Personality routine says to transfer control to landing pad.
// We may get control back if landing pad calls _Unwind_Resume().
if (_LIBUNWIND_TRACING_UNWINDING) {
unw_word_t pc;
unw_get_reg(&cursor2, UNW_REG_IP, &pc);
unw_get_reg(&cursor2, UNW_REG_SP, &sp);
_LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): re-entering "
"user code with ip=0x%llX, sp=0x%llX\n",
exception_object, pc, sp);
}
unw_resume(&cursor2);
// unw_resume() only returns if there was an error.
return _URC_FATAL_PHASE2_ERROR;
default:
// Personality routine returned an unknown result code.
_LIBUNWIND_DEBUG_LOG("personality function returned unknown result %d",
personalityResult);
return _URC_FATAL_PHASE2_ERROR;
}
}
}
// Clean up phase did not resume at the frame that the search phase
// said it would...
return _URC_FATAL_PHASE2_ERROR;
}
