/* Loop optimization. */
int lj_opt_loop(jit_State *J)
{
IRRef nins = J->cur.nins;
SnapNo nsnap = J->cur.nsnap;
MSize nsnapmap = J->cur.nsnapmap;
int errcode = lj_vm_cpcall(J->L, NULL, J, cploop_opt);
if (LJ_UNLIKELY(errcode)) {
lua_State *L = J->L;
if (errcode == LUA_ERRRUN && tvisnumber(L->top-1)) { /* Trace error? */
int32_t e = numberVint(L->top-1);
switch ((TraceError)e) {
case LJ_TRERR_TYPEINS: /* Type instability. */
case LJ_TRERR_GFAIL: /* Guard would always fail. */
/* Unrolling via recording fixes many cases, e.g. a flipped boolean. */
if (--J->instunroll < 0) /* But do not unroll forever. */
break;
L->top--; /* Remove error object. */
loop_undo(J, nins, nsnap, nsnapmap);
return 1; /* Loop optimization failed, continue recording. */
default:
break;
}
}
lj_err_throw(L, errcode); /* Propagate all other errors. */
}
return 0; /* Loop optimization is ok. */
}
static void LJ_FASTCALL recff_ipairs_aux(jit_State *J, RecordFFData *rd)
{
RecordIndex ix;
ix.tab = J->base[0];
if (tref_istab(ix.tab)) {
if (!tvisnumber(&rd->argv[1])) /* No support for string coercion. */
lj_trace_err(J, LJ_TRERR_BADTYPE);
setintV(&ix.keyv, numberVint(&rd->argv[1])+1);
settabV(J->L, &ix.tabv, tabV(&rd->argv[0]));
ix.val = 0; ix.idxchain = 0;
ix.key = lj_opt_narrow_toint(J, J->base[1]);
J->base[0] = ix.key = emitir(IRTI(IR_ADD), ix.key, lj_ir_kint(J, 1));
J->base[1] = lj_record_idx(J, &ix);
rd->nres = tref_isnil(J->base[1]) ? 0 : 2;
} /* else: Interpreter will throw. */
}
