compiler-builtins-zynq/src/int/mod.rs

369 lines
9.1 KiB
Rust

use core::ops;
macro_rules! hty {
($ty:ty) => {
<$ty as LargeInt>::HighHalf
};
}
macro_rules! os_ty {
($ty:ty) => {
<$ty as Int>::OtherSign
};
}
pub mod addsub;
pub mod mul;
pub mod sdiv;
pub mod shift;
pub mod udiv;
/// Trait for some basic operations on integers
pub(crate) trait Int:
Copy
+ PartialEq
+ PartialOrd
+ ops::AddAssign
+ ops::BitAndAssign
+ ops::BitOrAssign
+ ops::ShlAssign<i32>
+ ops::ShrAssign<u32>
+ ops::Add<Output = Self>
+ ops::Sub<Output = Self>
+ ops::Div<Output = Self>
+ ops::Shl<u32, Output = Self>
+ ops::Shr<u32, Output = Self>
+ ops::BitOr<Output = Self>
+ ops::BitXor<Output = Self>
+ ops::BitAnd<Output = Self>
+ ops::Not<Output = Self>
{
/// Type with the same width but other signedness
type OtherSign: Int;
/// Unsigned version of Self
type UnsignedInt: Int;
/// The bitwidth of the int type
const BITS: u32;
const ZERO: Self;
const ONE: Self;
/// Extracts the sign from self and returns a tuple.
///
/// # Examples
///
/// ```rust,ignore
/// let i = -25_i32;
/// let (sign, u) = i.extract_sign();
/// assert_eq!(sign, true);
/// assert_eq!(u, 25_u32);
/// ```
fn extract_sign(self) -> (bool, Self::UnsignedInt);
fn unsigned(self) -> Self::UnsignedInt;
fn from_unsigned(unsigned: Self::UnsignedInt) -> Self;
fn from_bool(b: bool) -> Self;
// copied from primitive integers, but put in a trait
fn max_value() -> Self;
fn min_value() -> Self;
fn wrapping_add(self, other: Self) -> Self;
fn wrapping_mul(self, other: Self) -> Self;
fn wrapping_sub(self, other: Self) -> Self;
fn wrapping_shl(self, other: u32) -> Self;
fn overflowing_add(self, other: Self) -> (Self, bool);
fn aborting_div(self, other: Self) -> Self;
fn aborting_rem(self, other: Self) -> Self;
fn leading_zeros(self) -> u32;
}
fn unwrap<T>(t: Option<T>) -> T {
match t {
Some(t) => t,
None => ::abort(),
}
}
macro_rules! int_impl_common {
($ty:ty, $bits:expr) => {
const BITS: u32 = $bits;
const ZERO: Self = 0;
const ONE: Self = 1;
fn from_bool(b: bool) -> Self {
b as $ty
}
fn max_value() -> Self {
<Self>::max_value()
}
fn min_value() -> Self {
<Self>::min_value()
}
fn wrapping_add(self, other: Self) -> Self {
<Self>::wrapping_add(self, other)
}
fn wrapping_mul(self, other: Self) -> Self {
<Self>::wrapping_mul(self, other)
}
fn wrapping_sub(self, other: Self) -> Self {
<Self>::wrapping_sub(self, other)
}
fn wrapping_shl(self, other: u32) -> Self {
<Self>::wrapping_shl(self, other)
}
fn overflowing_add(self, other: Self) -> (Self, bool) {
<Self>::overflowing_add(self, other)
}
fn aborting_div(self, other: Self) -> Self {
unwrap(<Self>::checked_div(self, other))
}
fn aborting_rem(self, other: Self) -> Self {
unwrap(<Self>::checked_rem(self, other))
}
fn leading_zeros(self) -> u32 {
<Self>::leading_zeros(self)
}
};
}
macro_rules! int_impl {
($ity:ty, $uty:ty, $bits:expr) => {
impl Int for $uty {
type OtherSign = $ity;
type UnsignedInt = $uty;
fn extract_sign(self) -> (bool, $uty) {
(false, self)
}
fn unsigned(self) -> $uty {
self
}
fn from_unsigned(me: $uty) -> Self {
me
}
int_impl_common!($uty, $bits);
}
impl Int for $ity {
type OtherSign = $uty;
type UnsignedInt = $uty;
fn extract_sign(self) -> (bool, $uty) {
if self < 0 {
(true, (!(self as $uty)).wrapping_add(1))
} else {
(false, self as $uty)
}
}
fn unsigned(self) -> $uty {
self as $uty
}
fn from_unsigned(me: $uty) -> Self {
me as $ity
}
int_impl_common!($ity, $bits);
}
};
}
int_impl!(i32, u32, 32);
int_impl!(i64, u64, 64);
int_impl!(i128, u128, 128);
/// Trait to convert an integer to/from smaller parts
pub(crate) trait LargeInt: Int {
type LowHalf: Int;
type HighHalf: Int;
fn low(self) -> Self::LowHalf;
fn low_as_high(low: Self::LowHalf) -> Self::HighHalf;
fn high(self) -> Self::HighHalf;
fn high_as_low(low: Self::HighHalf) -> Self::LowHalf;
fn from_parts(low: Self::LowHalf, high: Self::HighHalf) -> Self;
}
macro_rules! large_int {
($ty:ty, $tylow:ty, $tyhigh:ty, $halfbits:expr) => {
impl LargeInt for $ty {
type LowHalf = $tylow;
type HighHalf = $tyhigh;
fn low(self) -> $tylow {
self as $tylow
}
fn low_as_high(low: $tylow) -> $tyhigh {
low as $tyhigh
}
fn high(self) -> $tyhigh {
(self >> $halfbits) as $tyhigh
}
fn high_as_low(high: $tyhigh) -> $tylow {
high as $tylow
}
fn from_parts(low: $tylow, high: $tyhigh) -> $ty {
low as $ty | ((high as $ty) << $halfbits)
}
}
};
}
large_int!(u64, u32, u32, 32);
large_int!(i64, u32, i32, 32);
large_int!(u128, u64, u64, 64);
large_int!(i128, u64, i64, 64);
/// Trait to express (possibly lossy) casting of integers
pub(crate) trait CastInto<T: Copy>: Copy {
fn cast(self) -> T;
}
macro_rules! cast_into {
($ty:ty) => {
cast_into!($ty; usize, isize, u32, i32, u64, i64, u128, i128);
};
($ty:ty; $($into:ty),*) => {$(
impl CastInto<$into> for $ty {
fn cast(self) -> $into {
self as $into
}
}
)*};
}
cast_into!(u32);
cast_into!(i32);
cast_into!(u64);
cast_into!(i64);
cast_into!(u128);
cast_into!(i128);
pub(crate) trait WideInt: Int {
type Output: Int;
fn wide_mul(self, other: Self) -> (Self, Self);
fn wide_shift_left(&mut self, low: &mut Self, count: i32);
fn wide_shift_right_with_sticky(&mut self, low: &mut Self, count: i32);
}
macro_rules! impl_wide_int {
($ty:ty, $tywide:ty, $bits:expr) => {
impl WideInt for $ty {
type Output = $ty;
fn wide_mul(self, other: Self) -> (Self, Self) {
let product = (self as $tywide).wrapping_mul(other as $tywide);
((product >> ($bits as $ty)) as $ty, product as $ty)
}
fn wide_shift_left(&mut self, low: &mut Self, count: i32) {
*self = (*self << count) | (*low >> ($bits - count));
*low = *low << count;
}
fn wide_shift_right_with_sticky(&mut self, low: &mut Self, count: i32) {
if count < $bits {
let sticky = *low << ($bits - count);
*low = *self << ($bits - count) | *low >> count | sticky;
*self = *self >> count;
} else if count < 2 * $bits {
let sticky = *self << (2 * $bits - count) | *low;
*low = *self >> (count - $bits) | sticky;
*self = 0;
} else {
let sticky = *self | *low;
*self = sticky;
*self = 0;
}
}
}
};
}
impl_wide_int!(u32, u64, 32);
impl_wide_int!(u64, u128, 64);
intrinsics! {
#[maybe_use_optimized_c_shim]
#[cfg(any(
target_pointer_width = "16",
target_pointer_width = "32",
target_pointer_width = "64"
))]
pub extern "C" fn __clzsi2(x: usize) -> usize {
// TODO: const this? Would require const-if
// Note(Lokathor): the `intrinsics!` macro can't process mut inputs
let mut x = x;
let mut y: usize;
let mut n: usize = {
#[cfg(target_pointer_width = "64")]
{
64
}
#[cfg(target_pointer_width = "32")]
{
32
}
#[cfg(target_pointer_width = "16")]
{
16
}
};
#[cfg(target_pointer_width = "64")]
{
y = x >> 32;
if y != 0 {
n -= 32;
x = y;
}
}
#[cfg(any(target_pointer_width = "32", target_pointer_width = "64"))]
{
y = x >> 16;
if y != 0 {
n -= 16;
x = y;
}
}
y = x >> 8;
if y != 0 {
n -= 8;
x = y;
}
y = x >> 4;
if y != 0 {
n -= 4;
x = y;
}
y = x >> 2;
if y != 0 {
n -= 2;
x = y;
}
y = x >> 1;
if y != 0 {
n - 2
} else {
n - x
}
}
}