(a) After a verdict against the defendant, if the judgment is not arrested or a new trial granted, the court shall pronounce judgment.
(b) If, in the pronouncement of a judgment where a defendant has been retried either following an order granting a retrial by a court of this state or in obedience to a decision of a court of the United States, it becomes necessary that the jury's verdict be modified to prevent a sentence on the second trial being greater than the verdict pronounced at the first trial, then the trial court is authorized to modify the jury's verdict and pronounce judgment accordingly.