"When the Messenger of Allah wanted to sleep and he was sexually impure, he would perform ablution as for prayer." (Using translation from Ibn Mājah 584)
كَانَ رَسُولُ اللهِ ﷺ إِذَا أَرَادَ أَنْ يَنَامَ وَهُوَ جُنُبٌ تَوَضَّأَ وُضُوءَهُ لِلصَّلَاةِ فَإِذَا أَرَادَ أَنْ يَأْكُلَ غَسَلَ يَدَيْهِ ثُمَّ أَكَلَ