/* DWARF2 personality handler referenced from interpreter .eh_frame. */
LJ_FUNCA int lj_err_unwind_dwarf(int version, _Unwind_Action actions,
uint64_t uexclass, struct _Unwind_Exception *uex,
struct _Unwind_Context *ctx)
{
void *cf;
lua_State *L;
if (version != 1)
return _URC_FATAL_PHASE1_ERROR;
UNUSED(uexclass);
cf = (void *)_Unwind_GetCFA(ctx);
L = cframe_L(cf);
if ((actions & _UA_SEARCH_PHASE)) {
#if LJ_UNWIND_EXT
if (err_unwind(L, cf, 0) == NULL)
return _URC_CONTINUE_UNWIND;
#endif
if (!LJ_UEXCLASS_CHECK(uexclass)) {
setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP));
}
return _URC_HANDLER_FOUND;
}
if ((actions & _UA_CLEANUP_PHASE)) {
int errcode;
if (LJ_UEXCLASS_CHECK(uexclass)) {
errcode = LJ_UEXCLASS_ERRCODE(uexclass);
} else {
if ((actions & _UA_HANDLER_FRAME))
_Unwind_DeleteException(uex);
errcode = LUA_ERRRUN;
}
#if LJ_UNWIND_EXT
cf = err_unwind(L, cf, errcode);
if ((actions & _UA_FORCE_UNWIND)) {
return _URC_CONTINUE_UNWIND;
} else if (cf) {
_Unwind_SetGR(ctx, LJ_TARGET_EHRETREG, errcode);
_Unwind_SetIP(ctx, (uintptr_t)(cframe_unwind_ff(cf) ?
lj_vm_unwind_ff_eh :
lj_vm_unwind_c_eh));
return _URC_INSTALL_CONTEXT;
}
#if LJ_TARGET_X86ORX64
else if ((actions & _UA_HANDLER_FRAME)) {
/* Workaround for ancient libgcc bug. Still present in RHEL 5.5. :-/
** Real fix: http://gcc.gnu.org/viewcvs/trunk/gcc/unwind-dw2.c?r1=121165&r2=124837&pathrev=153877&diff_format=h
*/
_Unwind_SetGR(ctx, LJ_TARGET_EHRETREG, errcode);
_Unwind_SetIP(ctx, (uintptr_t)lj_vm_unwind_rethrow);
return _URC_INSTALL_CONTEXT;
}
#endif
#else
/* This is not the proper way to escape from the unwinder. We get away with
** it on x86/PPC because the interpreter restores all callee-saved regs.
*/
lj_err_throw(L, errcode);
#endif
}
return _URC_CONTINUE_UNWIND;
}
static _Unwind_Reason_Code
unwind_stop (int version, _Unwind_Action actions,
_Unwind_Exception_Class exc_class,
struct _Unwind_Exception *exc_obj,
struct _Unwind_Context *context, void *stop_parameter)
{
struct pthread_unwind_buf *buf = stop_parameter;
struct pthread *self = THREAD_SELF;
struct _pthread_cleanup_buffer *curp = THREAD_GETMEM (self, cleanup);
int do_longjump = 0;
/* Adjust all pointers used in comparisons, so that top of thread's
stack is at the top of address space. Without that, things break
if stack is allocated above the main stack. */
uintptr_t adj = (uintptr_t) self->stackblock + self->stackblock_size;
/* Do longjmp if we're at "end of stack", aka "end of unwind data".
We assume there are only C frame without unwind data in between
here and the jmp_buf target. Otherwise simply note that the CFA
of a function is NOT within it's stack frame; it's the SP of the
previous frame. */
if ((actions & _UA_END_OF_STACK)
|| ! _JMPBUF_CFA_UNWINDS_ADJ (buf->cancel_jmp_buf[0].jmp_buf, context,
adj))
do_longjump = 1;
if (__builtin_expect (curp != NULL, 0))
{
/* Handle the compatibility stuff. Execute all handlers
registered with the old method which would be unwound by this
step. */
struct _pthread_cleanup_buffer *oldp = buf->priv.data.cleanup;
void *cfa = (void *) (_Unwind_Ptr) _Unwind_GetCFA (context);
if (curp != oldp && (do_longjump || FRAME_LEFT (cfa, curp, adj)))
{
do
{
/* Pointer to the next element. */
struct _pthread_cleanup_buffer *nextp = curp->__prev;
/* Call the handler. */
curp->__routine (curp->__arg);
/* To the next. */
curp = nextp;
}
while (curp != oldp
&& (do_longjump || FRAME_LEFT (cfa, curp, adj)));
/* Mark the current element as handled. */
THREAD_SETMEM (self, cleanup, curp);
}
}
if (do_longjump)
__libc_unwind_longjmp ((struct __jmp_buf_tag *) buf->cancel_jmp_buf, 1);
return _URC_NO_REASON;
}
static _Unwind_Reason_Code
thread_unwind_stop(int version, _Unwind_Action actions,
int64_t exc_class,
struct _Unwind_Exception *exc_obj,
struct _Unwind_Context *context, void *stop_parameter)
{
struct pthread *curthread = _get_curthread();
struct pthread_cleanup *cur;
uintptr_t cfa;
int done = 0;
/* XXX assume stack grows down to lower address */
cfa = _Unwind_GetCFA(context);
if (actions & _UA_END_OF_STACK ||
cfa >= (uintptr_t)curthread->unwind_stackend) {
done = 1;
}
while ((cur = curthread->cleanup) != NULL &&
(done || (uintptr_t)cur <= cfa)) {
__pthread_cleanup_pop_imp(1);
}
if (done)
exit_thread(); /* Never return! */
return (_URC_NO_REASON);
}
_Unwind_Reason_Code trace_callback(_Unwind_Context* ctx,void* ptr)
{
if (!ptr)
return _URC_NO_REASON;
trace_data& d = *(reinterpret_cast<trace_data*>(ptr));
// First call.
if (std::size_t(-1) != d.count_)
{
// Get the instruction pointer for this frame.
d.array_[d.count_] = reinterpret_cast<void *>(_Unwind_GetIP(ctx));
// Get the CFA.
std::uint64_t cfa = _Unwind_GetCFA(ctx);
// Check if we're at the end of the stack.
if ((0 < d.count_) &&
(d.array_[d.count_ - 1] == d.array_[d.count_]) &&
(cfa == d.cfa_))
{
return _URC_END_OF_STACK;
}
d.cfa_ = cfa;
}
if (++d.count_ == d.size_)
return _URC_END_OF_STACK;
return _URC_NO_REASON;
}
static _Unwind_Reason_Code
UtilSymbolBacktraceFromPointerCallback(struct _Unwind_Context *ctx, // IN: Unwind context
void *cbData) // IN/OUT: Our status
{
struct UtilBacktraceFromPointerData *data = cbData;
uintptr_t cfa = _Unwind_GetCFA(ctx);
/*
* Stack grows down. So if we are below basePtr, do nothing...
*/
if (cfa >= data->basePtr && data->frameNr < 500) {
#ifndef VM_X86_64
# error You should not build this on 32bit - there is no eh_frame there.
#endif
void *enclFuncAddr;
Dl_info dli;
/* bump basePtr for glibc unwind bug, see [302237] */
data->basePtr = cfa + 8;
#ifdef __linux__
enclFuncAddr = _Unwind_FindEnclosingFunction((void *)_Unwind_GetIP(ctx));
#else
enclFuncAddr = NULL;
#endif
if (dladdr(enclFuncAddr, &dli) ||
dladdr((void *)_Unwind_GetIP(ctx), &dli)) {
data->outFunc(data->outFuncData,
"SymBacktrace[%u] %016lx rip=%016lx in function %s "
"in object %s loaded at %016lx\n",
data->frameNr, cfa, _Unwind_GetIP(ctx),
dli.dli_sname, dli.dli_fname, dli.dli_fbase);
} else {
data->outFunc(data->outFuncData,
"SymBacktrace[%u] %016lx rip=%016lx \n",
data->frameNr, cfa, _Unwind_GetIP(ctx));
}
data->frameNr++;
return _URC_NO_REASON;
} else if (data->skippedFrames < MAX_SKIPPED_FRAMES && !data->frameNr) {
/*
* Skip over the frames before the specified starting point of the
* backtrace.
*/
data->skippedFrames++;
return _URC_NO_REASON;
}
return _URC_END_OF_STACK;
}
_Unwind_Reason_Code
EJS_PERSONALITY(int version,
_Unwind_Action actions,
uint64_t exceptionClass,
struct _Unwind_Exception *exceptionObject,
struct _Unwind_Context *context)
{
//SPEW(_ejs_log ("EXCEPTIONS: %s through frame [ip=%p sp=%p] "
SPEW(_ejs_log ("EXCEPTIONS: through frame [ip=%p sp=%p] "
"for exception %p\n",
(void*)(_Unwind_GetIP(context)-1),
(void*)_Unwind_GetCFA(context), exceptionObject));
// Let C++ handle the unwind itself.
return CXX_PERSONALITY(version, actions, exceptionClass,
exceptionObject, context);
}
static _Unwind_Reason_Code
UtilBacktraceToBufferCallback(struct _Unwind_Context *ctx, // IN: Unwind context
void *cbData) // IN/OUT: Our data
{
struct UtilBacktraceToBufferData *data = cbData;
uintptr_t cfa = _Unwind_GetCFA(ctx);
/*
* Stack grows down. So if we are below basePtr, do nothing...
*/
if (cfa >= data->basePtr) {
if (data->len) {
*data->buffer++ = _Unwind_GetIP(ctx);
data->len--;
} else {
return _URC_END_OF_STACK;
}
}
return _URC_NO_REASON;
}
static _Unwind_Reason_Code
UtilBacktraceFromPointerCallback(struct _Unwind_Context *ctx, // IN: Unwind context
void *cbData) // IN/OUT: Our status
{
struct UtilBacktraceFromPointerData *data = cbData;
uintptr_t cfa = _Unwind_GetCFA(ctx);
/*
* Stack grows down. So if we are below basePtr, do nothing...
*/
if (cfa >= data->basePtr && data->frameNr < 500) {
#ifndef VM_X86_64
# error You should not build this on 32bit - there is no eh_frame there.
#endif
/* bump basePtr for glibc unwind bug, see [302237] */
data->basePtr = cfa + 8;
/* Do output without leading '0x' to save some horizontal space... */
data->outFunc(data->outFuncData,
"Backtrace[%u] %016lx rip=%016lx rbx=%016lx rbp=%016lx "
"r12=%016lx r13=%016lx r14=%016lx r15=%016lx\n",
data->frameNr, cfa, _Unwind_GetIP(ctx),
_Unwind_GetGR(ctx, 3), _Unwind_GetGR(ctx, 6),
_Unwind_GetGR(ctx, 12), _Unwind_GetGR(ctx, 13),
_Unwind_GetGR(ctx, 14), _Unwind_GetGR(ctx, 15));
data->frameNr++;
return _URC_NO_REASON;
} else if (data->skippedFrames < MAX_SKIPPED_FRAMES && !data->frameNr) {
/*
* Skip over the frames before the specified starting point of the
* backtrace.
*/
data->skippedFrames++;
return _URC_NO_REASON;
}
return _URC_END_OF_STACK;
}
