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#define CLEANUP_FOUND 0x01
#define HANDLER_FOUND 0x02
struct _Unwind_Context;
typedef enum
{
_URC_OK = 0,
_URC_FATAL_PHASE1_ERROR = 3,
_URC_END_OF_STACK = 5,
_URC_HANDLER_FOUND = 6,
_URC_INSTALL_CONTEXT = 7,
_URC_CONTINUE_UNWIND = 8
_URC_CONTINUE_UNWIND = 8,
_URC_FAILURE = 9
} _Unwind_Reason_Code;
struct objc_exception {
struct _Unwind_Exception {
uint64_t class;
void (*cleanup)(_Unwind_Reason_Code, struct _Unwind_Exception*);
#if defined(__arm__) || defined(__ARM__)
/* From "Exception Handling ABI for the ARM(R) Architecture" */
struct {
uint32_t reserved1, reserved2, reserved3, reserved4;
uint32_t reserved;
} unwinder_cache;
struct {
uint32_t sp;
uint32_t bitpattern[5];
} barrier_cache;
struct {
uint32_t bitpattern[4];
} cleanup_cache;
struct {
uint32_t fnstart;
uint32_t *ehtp;
uint32_t additional;
uint32_t reserved1;
} pr_cache;
long long int : 0;
#else
/*
* The Itanium Exception ABI says to have those and never touch
* them.
*/
uintptr_t private1, private2;
#endif
} exception;
id object;
#if !defined(__arm__) && !defined(__ARM__)
uintptr_t landingpad;
intptr_t filter;
#endif
};
struct lsda {
uintptr_t region_start, landingpads_start;
uint8_t typestable_enc;
const uint8_t *typestable;
uintptr_t typestable_base;
uint8_t callsites_enc;
const uint8_t *callsites, *actiontable;
};
extern _Unwind_Reason_Code _Unwind_RaiseException(struct _Unwind_Exception*);
extern void* _Unwind_GetLanguageSpecificData(struct _Unwind_Context*);
extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context*);
extern uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context*);
extern uintptr_t _Unwind_GetTextRelBase(struct _Unwind_Context*);
#if defined(__arm__) || defined(__ARM__)
extern _Unwind_Reason_Code __gnu_unwind_frame(struct _Unwind_Exception*,
struct _Unwind_Context*);
extern int _Unwind_VRS_Get(struct _Unwind_Context*, int, uint32_t, int, void*);
extern int _Unwind_VRS_Set(struct _Unwind_Context*, int, uint32_t, int, void*);
# define CONTINUE_UNWIND \
{ \
if (__gnu_unwind_frame(ex, ctx) != _URC_OK) \
return _URC_FAILURE; \
\
return _URC_CONTINUE_UNWIND; \
}
static inline uintptr_t
_Unwind_GetGR(struct _Unwind_Context *ctx, int regno)
{
uintptr_t value;
_Unwind_VRS_Get(ctx, 0, regno, 0, &value);
return value;
}
static inline uintptr_t
_Unwind_GetIP(struct _Unwind_Context *ctx)
{
return _Unwind_GetGR(ctx, 15) & ~1;
}
static inline void
_Unwind_SetGR(struct _Unwind_Context *ctx, int regno, uintptr_t value)
{
_Unwind_VRS_Set(ctx, 0, regno, 0, &value);
}
static inline void
_Unwind_SetIP(struct _Unwind_Context *ctx, uintptr_t value)
{
uintptr_t thumb = _Unwind_GetGR(ctx, 15) & 1;
_Unwind_SetGR(ctx, 15, (value | thumb));
}
#else
# define CONTINUE_UNWIND return _URC_CONTINUE_UNWIND
extern uintptr_t _Unwind_GetIP(struct _Unwind_Context*);
extern void _Unwind_SetIP(struct _Unwind_Context*, uintptr_t);
extern void _Unwind_SetGR(struct _Unwind_Context*, int, uintptr_t);
#endif
static objc_uncaught_exception_handler uncaught_exception_handler;
static uint64_t
read_uleb128(const uint8_t **ptr)
{
uint64_t value = 0;
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}
#undef READ_TYPE
return value;
}
#if !defined(__arm__) && !defined(__ARM__)
static uint64_t
resolve_value(uint64_t value, uint8_t enc, const uint8_t *start, uint64_t base)
{
if (value == 0)
return 0;
value += ((enc & 0x70) == DW_EH_PE_pcrel ? (uintptr_t)start : base);
if (enc & DW_EH_PE_indirect)
value = *(uint64_t*)(uintptr_t)value;
return value;
}
#endif
static void
read_lsda(struct _Unwind_Context *ctx, const uint8_t *ptr, struct lsda *lsda)
{
uint8_t landingpads_start_enc;
uintptr_t callsites_size;
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*/
actionrecords = ptr;
displacement = (intptr_t)read_sleb128(&ptr);
actionrecords += displacement;
if (filter > 0 && !(actions & _UA_FORCE_UNWIND) && !foreign) {
Class class;
uintptr_t i, c;
uintptr_t c;
const uint8_t *tmp;
#if defined(__arm__) || defined(__ARM__)
tmp = lsda->typestable - (filter * 4);
c = *(uintptr_t*)tmp;
if (c != 0) {
c += (uintptr_t)tmp;
c = *(uintptr_t*)c;
}
#else
uintptr_t i;
i = filter * size_for_encoding(lsda->typestable_enc);
tmp = lsda->typestable - i;
c = (uintptr_t)read_value(lsda->typestable_enc, &tmp);
c = (uintptr_t)resolve_value(c, lsda->typestable_enc,
lsda->typestable - i, lsda->typestable_base);
#endif
class = (c != 0 ? objc_get_class((const char*)c) : Nil);
if (class_matches(class, e->object)) {
*filtervalue = filter;
return (found | HANDLER_FOUND);
}
} else if (filter == 0)
found |= CLEANUP_FOUND;
else
abort();
} while (displacement != 0);
return found;
}
#if defined(__arm__) || defined(__ARM__)
_Unwind_Reason_Code
__gnu_objc_personality_v0(uint32_t state, struct _Unwind_Exception *ex,
struct _Unwind_Context *ctx)
{
int version = 1;
uint64_t ex_class = ex->class;
int actions;
switch (state) {
case 0: /* _US_VIRTUAL_UNWIND_FRAME */
actions = _UA_SEARCH_PHASE;
break;
case 1: /* _US_UNWIND_FRAME_STARTING */
actions = _UA_CLEANUP_PHASE;
if ((ex->barrier_cache.sp == _Unwind_GetGR(ctx, 13)) != 0)
actions |= _UA_HANDLER_FRAME;
break;
case 2: /* _US_UNWIND_FRAME_RESUME */
CONTINUE_UNWIND;
default:
return _URC_FAILURE;
}
_Unwind_SetGR(ctx, 12, (uintptr_t)ex);
#else
_Unwind_Reason_Code
__gnu_objc_personality_v0(int version, int actions, uint64_t ex_class,
struct _Unwind_Exception *ex, struct _Unwind_Context *ctx)
{
#endif
struct objc_exception *e = (struct objc_exception*)ex;
BOOL foreign = (ex_class != objc_exception_class);
const uint8_t *lsda_addr, *actionrecords;
struct lsda lsda;
uintptr_t landingpad = 0;
uint8_t found = 0;
intptr_t filter = 0;
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if (actions & _UA_HANDLER_FRAME && !foreign) {
/*
* For handlers, reg #0 must be the exception's object and reg
* #1 the filter.
*/
_Unwind_SetGR(ctx, __builtin_eh_return_data_regno(0),
(uintptr_t)e->object);
#if defined(__arm__) || defined(__ARM__)
_Unwind_SetGR(ctx, __builtin_eh_return_data_regno(1),
ex->barrier_cache.bitpattern[1]);
_Unwind_SetIP(ctx, ex->barrier_cache.bitpattern[3]);
#else
_Unwind_SetGR(ctx, __builtin_eh_return_data_regno(1),
e->filter);
_Unwind_SetIP(ctx, e->landingpad);
#endif
free(ex);
return _URC_INSTALL_CONTEXT;
}
/* No LSDA -> nothing to handle */
if ((lsda_addr = _Unwind_GetLanguageSpecificData(ctx)) == NULL)
return _URC_CONTINUE_UNWIND;
CONTINUE_UNWIND;
read_lsda(ctx, lsda_addr, &lsda);
if (!find_callsite(ctx, &lsda, &landingpad, &actionrecords))
return _URC_CONTINUE_UNWIND;
CONTINUE_UNWIND;
if (landingpad != 0 && actionrecords == NULL)
found = CLEANUP_FOUND;
else if (landingpad != 0)
found = find_actionrecord(actionrecords, &lsda, actions,
foreign, e, &filter);
if (!found)
return _URC_CONTINUE_UNWIND;
CONTINUE_UNWIND;
if (actions & _UA_SEARCH_PHASE) {
if (!(found & HANDLER_FOUND))
return _URC_CONTINUE_UNWIND;
CONTINUE_UNWIND;
/* Cache it so we don't have to search it again in phase 2 */
if (!foreign) {
#if defined(__arm__) || defined(__ARM__)
ex->barrier_cache.sp = _Unwind_GetGR(ctx, 13);
ex->barrier_cache.bitpattern[1] = filter;
ex->barrier_cache.bitpattern[3] = landingpad;
#else
e->landingpad = landingpad;
e->filter = filter;
#endif
}
return _URC_HANDLER_FOUND;
} else if (actions & _UA_CLEANUP_PHASE) {
/* For cleanup, reg #0 must be the exception and reg #1 zero */
_Unwind_SetGR(ctx, __builtin_eh_return_data_regno(0),
(uintptr_t)e);
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objc_exception_throw(id object)
{
struct objc_exception *e;
if ((e = malloc(sizeof(*e))) == NULL)
abort();
memset(e, 0, sizeof(*e));
e->exception.class = objc_exception_class;
e->exception.cleanup = cleanup;
e->exception.private1 = e->exception.private2 = 0;
e->object = object;
if (_Unwind_RaiseException(&e->exception) == _URC_END_OF_STACK &&
uncaught_exception_handler != NULL)
uncaught_exception_handler(object);
abort();
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