/* Helper for equality comparisons. __eq metamethod. */
TValue *lj_meta_equal(lua_State *L, GCobj *o1, GCobj *o2, int ne)
{
/* Field metatable must be at same offset for GCtab and GCudata! */
cTValue *mo = lj_meta_fast(L, tabref(o1->gch.metatable), MM_eq);
if (mo) {
TValue *top;
uint32_t it;
if (tabref(o1->gch.metatable) != tabref(o2->gch.metatable)) {
cTValue *mo2 = lj_meta_fast(L, tabref(o2->gch.metatable), MM_eq);
if (mo2 == NULL || !lj_obj_equal(mo, mo2))
return (TValue *)(intptr_t)ne;
}
top = curr_top(L);
setcont(top, ne ? lj_cont_condf : lj_cont_condt);
copyTV(L, top+1, mo);
it = ~(uint32_t)o1->gch.gct;
setgcV(L, top+2, o1, it);
setgcV(L, top+3, o2, it);
return top+2; /* Trigger metamethod call. */
}
return (TValue *)(intptr_t)ne;
}
/* Helper for TSET*. __newindex chain and metamethod. */
TValue *lj_meta_tset(lua_State *L, cTValue *o, cTValue *k)
{
TValue tmp;
int loop;
for (loop = 0; loop < LJ_MAX_IDXCHAIN; loop++) {
cTValue *mo;
if (LJ_LIKELY(tvistab(o))) {
GCtab *t = tabV(o);
cTValue *tv = lj_tab_get(L, t, k);
if (LJ_LIKELY(!tvisnil(tv))) {
t->nomm = 0; /* Invalidate negative metamethod cache. */
lj_gc_anybarriert(L, t);
return (TValue *)tv;
} else if (!(mo = lj_meta_fast(L, tabref(t->metatable), MM_newindex))) {
t->nomm = 0; /* Invalidate negative metamethod cache. */
lj_gc_anybarriert(L, t);
if (tv != niltv(L))
return (TValue *)tv;
if (tvisnil(k)) lj_err_msg(L, LJ_ERR_NILIDX);
else if (tvisint(k)) { setnumV(&tmp, (lua_Number)intV(k)); k = &tmp; }
else if (tvisnum(k) && tvisnan(k)) lj_err_msg(L, LJ_ERR_NANIDX);
return lj_tab_newkey(L, t, k);
}
} else if (tvisnil(mo = lj_meta_lookup(L, o, MM_newindex))) {
lj_err_optype(L, o, LJ_ERR_OPINDEX);
return NULL; /* unreachable */
}
if (tvisfunc(mo)) {
L->top = mmcall(L, lj_cont_nop, mo, o, k);
/* L->top+2 = v filled in by caller. */
return NULL; /* Trigger metamethod call. */
}
copyTV(L, &tmp, mo);
o = &tmp;
}
lj_err_msg(L, LJ_ERR_SETLOOP);
return NULL; /* unreachable */
}
/* Helper for TGET*. __index chain and metamethod. */
cTValue *lj_meta_tget(lua_State *L, cTValue *o, cTValue *k)
{
int loop;
for (loop = 0; loop < LJ_MAX_IDXCHAIN; loop++) {
cTValue *mo;
if (LJ_LIKELY(tvistab(o))) {
GCtab *t = tabV(o);
cTValue *tv = lj_tab_get(L, t, k);
if (!tvisnil(tv) ||
!(mo = lj_meta_fast(L, tabref(t->metatable), MM_index)))
return tv;
} else if (tvisnil(mo = lj_meta_lookup(L, o, MM_index))) {
lj_err_optype(L, o, LJ_ERR_OPINDEX);
return NULL; /* unreachable */
}
if (tvisfunc(mo)) {
L->top = mmcall(L, lj_cont_ra, mo, o, k);
return NULL; /* Trigger metamethod call. */
}
o = mo;
}
lj_err_msg(L, LJ_ERR_GETLOOP);
return NULL; /* unreachable */
}
