holey-bytes/hbvm/src/mem/addr.rs
2023-08-19 23:46:47 +02:00

111 lines
2.5 KiB
Rust

//! Virtual(?) memory address
use core::{fmt::Debug, ops};
use crate::utils::impl_display;
/// Memory address
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
pub struct Address(u64);
impl Address {
/// A null address
pub const NULL: Self = Self(0);
/// Saturating integer addition. Computes self + rhs, saturating at the numeric bounds instead of overflowing.
#[inline]
pub fn saturating_add<T: AddressOp>(self, rhs: T) -> Self {
Self(self.0.saturating_add(rhs.cast_u64()))
}
/// Saturating integer subtraction. Computes self - rhs, saturating at the numeric bounds instead of overflowing.
#[inline]
pub fn saturating_sub<T: AddressOp>(self, rhs: T) -> Self {
Self(self.0.saturating_sub(rhs.cast_u64()))
}
/// Cast or if smaller, truncate to [`usize`]
pub fn truncate_usize(self) -> usize {
self.0 as _
}
/// Get inner value
#[inline(always)]
pub fn get(self) -> u64 {
self.0
}
/// Construct new address
#[inline(always)]
pub fn new(val: u64) -> Self {
Self(val)
}
/// Do something with inner value
#[inline(always)]
pub fn map(self, f: impl Fn(u64) -> u64) -> Self {
Self(f(self.0))
}
}
impl_display!(for Address =>
|Address(a)| "{a:0x}"
);
impl<T: AddressOp> ops::Add<T> for Address {
type Output = Self;
#[inline]
fn add(self, rhs: T) -> Self::Output {
Self(self.0.wrapping_add(rhs.cast_u64()))
}
}
impl<T: AddressOp> ops::Sub<T> for Address {
type Output = Self;
#[inline]
fn sub(self, rhs: T) -> Self::Output {
Self(self.0.wrapping_sub(rhs.cast_u64()))
}
}
impl<T: AddressOp> ops::AddAssign<T> for Address {
fn add_assign(&mut self, rhs: T) {
self.0 = self.0.wrapping_add(rhs.cast_u64())
}
}
impl<T: AddressOp> ops::SubAssign<T> for Address {
fn sub_assign(&mut self, rhs: T) {
self.0 = self.0.wrapping_sub(rhs.cast_u64())
}
}
impl From<Address> for u64 {
#[inline(always)]
fn from(value: Address) -> Self {
value.0
}
}
impl Debug for Address {
fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
write!(f, "[{:0x}]", self.0)
}
}
/// Can perform address operations with
pub trait AddressOp {
/// Cast to u64, truncating or extending
fn cast_u64(self) -> u64;
}
macro_rules! impl_address_ops(($($ty:ty),* $(,)?) => {
$(impl AddressOp for $ty {
#[inline(always)]
fn cast_u64(self) -> u64 { self as _ }
})*
});
impl_address_ops!(u8, u16, u32, u64, usize);