use crate::machinst::{ABIArg, ABIArgSlot, ArgsAccumulator};

// Winch writes the first result to the highest offset, so we need to iterate through the

// args and adjust the offsets down.

pub(super) fn reverse_stack(mut args: ArgsAccumulator, next_stack: u32, uses_extension: bool) {

    for arg in args.args_mut() {

        if let ABIArg::Slots { slots, .. } = arg {

            for slot in slots.iter_mut() {

                if let ABIArgSlot::Stack { offset, ty, .. } = slot {

                    let size = if uses_extension {

                        i64::from(core::cmp::max(ty.bytes(), 8))

                    } else {

                        i64::from(ty.bytes())

                    };

                    *offset = i64::from(next_stack) - *offset - size;

                }

            }

        } else {

            unreachable!("Winch cannot handle {arg:?}");

        }

    }

}