Function luaK_indexed

third-party/lua-5.4.6/src/lcode.c:1280–1310

** Create expression 't[k]'. 't' must have its final result already in a ** register or upvalue. Upvalues can only be indexed by literal strings. ** Keys can be literal strings in the constant table or arbitrary ** values in registers. */

** values in registers.
*/
void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
  if (k->k == VKSTR)
    str2K(fs, k);
  lua_assert(!hasjumps(t) &&
             (t->k == VLOCAL || t->k == VNONRELOC || t->k == VUPVAL));
  if (t->k == VUPVAL && !isKstr(fs, k))  /* upvalue indexed by non 'Kstr'? */
    luaK_exp2anyreg(fs, t);  /* put it in a register */
  if (t->k == VUPVAL) {
    int temp = t->u.info;  /* upvalue index */
    lua_assert(isKstr(fs, k));
    t->u.ind.t = temp;  /* (can't do a direct assignment; values overlap) */
    t->u.ind.idx = k->u.info;  /* literal short string */
    t->k = VINDEXUP;
  }
  else {
    /* register index of the table */
    t->u.ind.t = (t->k == VLOCAL) ? t->u.var.ridx: t->u.info;
    if (isKstr(fs, k)) {
      t->u.ind.idx = k->u.info;  /* literal short string */
      t->k = VINDEXSTR;
    }
    else if (isCint(k)) {
      t->u.ind.idx = cast_int(k->u.ival);  /* int. constant in proper range */
      t->k = VINDEXI;
    }
    else {
      t->u.ind.idx = luaK_exp2anyreg(fs, k);  /* register */
      t->k = VINDEXED;
    }
  }
}


/*