/* Helper for ordered comparisons. String compare, __lt/__le metamethods. */
TValue *lj_meta_comp(lua_State *L, cTValue *o1, cTValue *o2, int op)
{
if (LJ_HASFFI && (tviscdata(o1) || tviscdata(o2))) {
ASMFunction cont = (op & 1) ? lj_cont_condf : lj_cont_condt;
MMS mm = (op & 2) ? MM_le : MM_lt;
cTValue *mo = lj_meta_lookup(L, tviscdata(o1) ? o1 : o2, mm);
if (LJ_UNLIKELY(tvisnil(mo))) goto err;
return mmcall(L, cont, mo, o1, o2);
} else if (LJ_52 || itype(o1) == itype(o2)) {
/* Never called with two numbers. */
if (tvisstr(o1) && tvisstr(o2)) {
int32_t res = lj_str_cmp(strV(o1), strV(o2));
return (TValue *)(intptr_t)(((op&2) ? res <= 0 : res < 0) ^ (op&1));
} else {
trymt:
while (1) {
ASMFunction cont = (op & 1) ? lj_cont_condf : lj_cont_condt;
MMS mm = (op & 2) ? MM_le : MM_lt;
cTValue *mo = lj_meta_lookup(L, o1, mm);
#if LJ_52
if (tvisnil(mo) && tvisnil((mo = lj_meta_lookup(L, o2, mm))))
#else
cTValue *mo2 = lj_meta_lookup(L, o2, mm);
if (tvisnil(mo) || !lj_obj_equal(mo, mo2))
#endif
{
if (op & 2) { /* MM_le not found: retry with MM_lt. */
cTValue *ot = o1; o1 = o2; o2 = ot; /* Swap operands. */
op ^= 3; /* Use LT and flip condition. */
continue;
}
goto err;
}
return mmcall(L, cont, mo, o1, o2);
}
}
} else if (tvisbool(o1) && tvisbool(o2)) {
goto trymt;
} else {
err:
lj_err_comp(L, o1, o2);
return NULL;
}
}
/* 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;
}
