/* Win64 exception handler for interpreter frame. */
LJ_FUNCA EXCEPTION_DISPOSITION lj_err_unwind_win64(EXCEPTION_RECORD *rec,
void *cf, CONTEXT *ctx, UndocumentedDispatcherContext *dispatch)
{
lua_State *L = cframe_L(cf);
int errcode = LJ_EXCODE_CHECK(rec->ExceptionCode) ?
LJ_EXCODE_ERRCODE(rec->ExceptionCode) : LUA_ERRRUN;
if ((rec->ExceptionFlags & 6)) { /* EH_UNWINDING|EH_EXIT_UNWIND */
/* Unwind internal frames. */
err_unwind(L, cf, errcode);
} else {
void *cf2 = err_unwind(L, cf, 0);
if (cf2) { /* We catch it, so start unwinding the upper frames. */
if (rec->ExceptionCode == LJ_MSVC_EXCODE) {
#ifdef _MSC_VER
__DestructExceptionObject(rec, 1);
#endif
setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP));
} else if (!LJ_EXCODE_CHECK(rec->ExceptionCode)) {
/* Don't catch access violations etc. */
return ExceptionContinueSearch;
}
/* Unwind the stack and call all handlers for all lower C frames
** (including ourselves) again with EH_UNWINDING set. Then set
** rsp = cf, rax = errcode and jump to the specified target.
*/
RtlUnwindEx(cf, (void *)((cframe_unwind_ff(cf2) && errcode != LUA_YIELD) ?
lj_vm_unwind_ff_eh :
lj_vm_unwind_c_eh),
rec, (void *)errcode, ctx, dispatch->HistoryTable);
/* RtlUnwindEx should never return. */
}
}
return ExceptionContinueSearch;
}
/* 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;
}
/* ARM unwinder personality handler referenced from interpreter .ARM.extab. */
LJ_FUNCA int lj_err_unwind_arm(int state, _Unwind_Control_Block *ucb,
_Unwind_Context *ctx)
{
void *cf = (void *)_Unwind_GetGR(ctx, 13);
lua_State *L = cframe_L(cf);
int errcode;
switch ((state & _US_ACTION_MASK)) {
case _US_VIRTUAL_UNWIND_FRAME:
if ((state & _US_FORCE_UNWIND)) break;
return _URC_HANDLER_FOUND;
case _US_UNWIND_FRAME_STARTING:
if (LJ_UEXCLASS_CHECK(ucb->exclass)) {
errcode = LJ_UEXCLASS_ERRCODE(ucb->exclass);
} else {
errcode = LUA_ERRRUN;
setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP));
}
cf = err_unwind(L, cf, errcode);
if ((state & _US_FORCE_UNWIND) || cf == NULL) break;
_Unwind_SetGR(ctx, 15, (uint32_t)lj_vm_unwind_ext);
_Unwind_SetGR(ctx, 0, (uint32_t)ucb);
_Unwind_SetGR(ctx, 1, (uint32_t)errcode);
_Unwind_SetGR(ctx, 2, cframe_unwind_ff(cf) ?
(uint32_t)lj_vm_unwind_ff_eh :
(uint32_t)lj_vm_unwind_c_eh);
return _URC_INSTALL_CONTEXT;
default:
return _URC_FAILURE;
}
if (__gnu_unwind_frame(ucb, ctx) != _URC_OK)
return _URC_FAILURE;
return _URC_CONTINUE_UNWIND;
}
/* Return bytecode position for function/frame or NO_BCPOS. */
static BCPos debug_framepc(lua_State *L, GCfunc *fn, cTValue *nextframe)
{
const BCIns *ins;
GCproto *pt;
BCPos pos;
lua_assert(fn->c.gct == ~LJ_TFUNC || fn->c.gct == ~LJ_TTHREAD);
if (!isluafunc(fn)) { /* Cannot derive a PC for non-Lua functions. */
return NO_BCPOS;
} else if (nextframe == NULL) { /* Lua function on top. */
void *cf = cframe_raw(L->cframe);
if (cf == NULL || (char *)cframe_pc(cf) == (char *)cframe_L(cf))
return NO_BCPOS;
ins = cframe_pc(cf); /* Only happens during error/hook handling. */
} else {
if (frame_islua(nextframe)) {
ins = frame_pc(nextframe);
} else if (frame_iscont(nextframe)) {
ins = frame_contpc(nextframe);
} else {
/* Lua function below errfunc/gc/hook: find cframe to get the PC. */
void *cf = cframe_raw(L->cframe);
TValue *f = L->base-1;
for (;;) {
if (cf == NULL)
return NO_BCPOS;
while (cframe_nres(cf) < 0) {
if (f >= restorestack(L, -cframe_nres(cf)))
break;
cf = cframe_raw(cframe_prev(cf));
if (cf == NULL)
return NO_BCPOS;
}
if (f < nextframe)
break;
if (frame_islua(f)) {
f = frame_prevl(f);
} else {
if (frame_isc(f) || (LJ_HASFFI && frame_iscont(f) &&
(f-1)->u32.lo == LJ_CONT_FFI_CALLBACK))
cf = cframe_raw(cframe_prev(cf));
f = frame_prevd(f);
}
}
ins = cframe_pc(cf);
}
}
pt = funcproto(fn);
pos = proto_bcpos(pt, ins) - 1;
#if LJ_HASJIT
if (pos > pt->sizebc) { /* Undo the effects of lj_trace_exit for JLOOP. */
GCtrace *T = (GCtrace *)((char *)(ins-1) - offsetof(GCtrace, startins));
lua_assert(bc_isret(bc_op(ins[-1])));
pos = proto_bcpos(pt, mref(T->startpc, const BCIns));
}
/* ARM unwinder personality handler referenced from interpreter .ARM.extab. */
LJ_FUNCA int lj_err_unwind_arm(int state, void *ucb, _Unwind_Context *ctx)
{
void *cf = (void *)_Unwind_GetGR(ctx, 13);
lua_State *L = cframe_L(cf);
if ((state & _US_ACTION_MASK) == _US_VIRTUAL_UNWIND_FRAME) {
setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP));
return _URC_HANDLER_FOUND;
}
if ((state&(_US_ACTION_MASK|_US_FORCE_UNWIND)) == _US_UNWIND_FRAME_STARTING) {
_Unwind_DeleteException(ucb);
_Unwind_SetGR(ctx, 15, (uint32_t)(void *)lj_err_throw);
_Unwind_SetGR(ctx, 0, (uint32_t)L);
_Unwind_SetGR(ctx, 1, (uint32_t)LUA_ERRRUN);
return _URC_INSTALL_CONTEXT;
}
if (__gnu_unwind_frame(ucb, ctx) != _URC_OK)
return _URC_FAILURE;
return _URC_CONTINUE_UNWIND;
}
