Floyd Mayweather -- Footing the Bill for Murderer's Funeral

Floyd Mayweather is putting aside some brutal facts and paying for the funeral of the rapper who gunned down his wife in the bathtub and then shot himself.

We're told Floyd thinks Earl Hayes' family deserves a proper funeral, despite the horrific thing he did.

TMZ broke the story ... Floyd was FaceTiming with Hayes earlier this month when the rapper snapped as they discussed how his wife, "Hit the Floor" star Stephanie Moseley was cheating on him. He went in the bathroom and pumped 10-12 shots as she lay in the tub. He then killed himself.

We don't know if Floyd foot the bill for Stephanie's funeral Friday in Canada. Floyd was urging Hayes to dump her just before he lost it.

Hayes' funeral is set for today.