// minimize varint encoding of their varp offset).
	if a.OpenDeferSlot() != b.OpenDeferSlot() {
		return a.OpenDeferSlot()
	}

	// If a and b are both open-coded defer slots, then order them by
	// index in descending order, so they'll be laid out in the frame in
	// ascending order.
	//
	// Their index was saved in FrameOffset in state.openDeferSave.
	if a.OpenDeferSlot() {
		return a.FrameOffset() > b.FrameOffset()
	}

				// prologue (from the result of a mallocgc) but we need to
				// zero it in case that malloc causes a stack scan.
				n.SetNeedzero(true)
				livedefer.Set(int32(i))
			}
			if n.OpenDeferSlot() {
				// Open-coded defer args slots must be live
				// everywhere in a function, since a panic can
				// occur (almost) anywhere. Because it is live
				// everywhere, it must be zeroed on entry.

	if base.Debug.MergeLocals == 0 ||
		base.Flag.N != 0 ||
		n.Class != ir.PAUTO ||
		n.Type().Size() <= int64(3*types.PtrSize) ||
		n.Addrtaken() ||
		n.NonMergeable() ||
		n.OpenDeferSlot() {
		return false
	}
	return true