pub fn head_of(ty: Type) -> Option<&'static str>Expand description
What the pseudo for an argument of that type is called.
The width is in the name for the same reason it is in every other opcode here: it is what the instruction is about. Nothing encodes it, so nothing depends on it being right, but a listing that says an argument arrived and does not say how much of it did is a listing worth less.
Which widths there are is the question the rule set asks of a type, and not a list of its own, because it has to be the same list. An argument brought in at a width the rules have no name for is a register nothing downstream could then read, and a width the rules cover that this refuses is a function turned away for no reason. Asking one question in one place is what keeps the two answers from drifting, and an address is what they used to disagree about.