Function luaK_dischargevars

third-party/lua-5.5.0/src/lcode.c:819–874

** Ensure that expression 'e' is not a variable (nor a ). ** (Expression still may have jump lists.) */

** (Expression still may have jump lists.)
*/
void luaK_dischargevars (FuncState *fs, expdesc *e) {
  switch (e->k) {
    case VCONST: {
      const2exp(const2val(fs, e), e);
      break;
    }
    case VVARGVAR: {
      luaK_vapar2local(fs, e);  /* turn it into a local variable */
    }  /* FALLTHROUGH */
    case VLOCAL: {  /* already in a register */
      int temp = e->u.var.ridx;
      e->u.info = temp;  /* (can't do a direct assignment; values overlap) */
      e->k = VNONRELOC;  /* becomes a non-relocatable value */
      break;
    }
    case VUPVAL: {  /* move value to some (pending) register */
      e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0);
      e->k = VRELOC;
      break;
    }
    case VINDEXUP: {
      e->u.info = luaK_codeABC(fs, OP_GETTABUP, 0, e->u.ind.t, e->u.ind.idx);
      e->k = VRELOC;
      break;
    }
    case VINDEXI: {
      freereg(fs, e->u.ind.t);
      e->u.info = luaK_codeABC(fs, OP_GETI, 0, e->u.ind.t, e->u.ind.idx);
      e->k = VRELOC;
      break;
    }
    case VINDEXSTR: {
      freereg(fs, e->u.ind.t);
      e->u.info = luaK_codeABC(fs, OP_GETFIELD, 0, e->u.ind.t, e->u.ind.idx);
      e->k = VRELOC;
      break;
    }
    case VINDEXED: {
      freeregs(fs, e->u.ind.t, e->u.ind.idx);
      e->u.info = luaK_codeABC(fs, OP_GETTABLE, 0, e->u.ind.t, e->u.ind.idx);
      e->k = VRELOC;
      break;
    }
    case VVARGIND: {
      freeregs(fs, e->u.ind.t, e->u.ind.idx);
      e->u.info = luaK_codeABC(fs, OP_GETVARG, 0, e->u.ind.t, e->u.ind.idx);
      e->k = VRELOC;
      break;
    }
    case VVARARG: case VCALL: {
      luaK_setoneret(fs, e);
      break;
    }
    default: break;  /* there is one value available (somewhere) */
  }
}