Function jumponcond

third-party/lua-5.5.0/src/lcode.c:1160–1172

** Emit instruction to jump if 'e' is 'cond' (that is, if 'cond' ** is true, code will jump if 'e' is true.) Return jump position. ** Optimize when 'e' is 'not' something, inverting the condition ** and removing the 'not'. */

** and removing the 'not'.
*/
static int jumponcond (FuncState *fs, expdesc *e, int cond) {
  if (e->k == VRELOC) {
    Instruction ie = getinstruction(fs, e);
    if (GET_OPCODE(ie) == OP_NOT) {
      removelastinstruction(fs);  /* remove previous OP_NOT */
      return condjump(fs, OP_TEST, GETARG_B(ie), 0, 0, !cond);
    }
    /* else go through */
  }
  discharge2anyreg(fs, e);
  freeexp(fs, e);
  return condjump(fs, OP_TESTSET, NO_REG, e->u.info, 0, cond);
}


/*