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// run-pass
// check raw fat pointer ops in mir
// FIXME: please improve this when we get monomorphization support
#![feature(raw_ref_op)]
use std::mem;
#[derive(Debug, PartialEq, Eq)]
struct ComparisonResults {
lt: bool,
le: bool,
gt: bool,
ge: bool,
eq: bool,
ne: bool
}
const LT: ComparisonResults = ComparisonResults {
lt: true,
le: true,
gt: false,
ge: false,
eq: false,
ne: true
};
const EQ: ComparisonResults = ComparisonResults {
lt: false,
le: true,
gt: false,
ge: true,
eq: true,
ne: false
};
const GT: ComparisonResults = ComparisonResults {
lt: false,
le: false,
gt: true,
ge: true,
eq: false,
ne: true
};
fn compare_su8(a: *const S<[u8]>, b: *const S<[u8]>) -> ComparisonResults {
ComparisonResults {
lt: a < b,
le: a <= b,
gt: a > b,
ge: a >= b,
eq: a == b,
ne: a != b
}
}
fn compare_au8(a: *const [u8], b: *const [u8]) -> ComparisonResults {
ComparisonResults {
lt: a < b,
le: a <= b,
gt: a > b,
ge: a >= b,
eq: a == b,
ne: a != b
}
}
fn compare_foo<'a>(a: *const (dyn Foo+'a), b: *const (dyn Foo+'a)) -> ComparisonResults {
ComparisonResults {
lt: a < b,
le: a <= b,
gt: a > b,
ge: a >= b,
eq: a == b,
ne: a != b
}
}
fn simple_eq<'a>(a: *const (dyn Foo+'a), b: *const (dyn Foo+'a)) -> bool {
let result = a == b;
result
}
fn assert_inorder<T: Copy>(a: &[T],
compare: fn(T, T) -> ComparisonResults) {
for i in 0..a.len() {
for j in 0..a.len() {
let cres = compare(a[i], a[j]);
if i < j {
assert_eq!(cres, LT);
} else if i == j {
assert_eq!(cres, EQ);
} else {
assert_eq!(cres, GT);
}
}
}
}
trait Foo { fn foo(&self) -> usize; }
impl<T> Foo for T {
fn foo(&self) -> usize {
mem::size_of::<T>()
}
}
#[allow(unused_tuple_struct_fields)]
struct S<T:?Sized>(u32, T);
fn main_ref() {
let array = [0,1,2,3,4];
let array2 = [5,6,7,8,9];
// fat ptr comparison: addr then extra
// check ordering for arrays
let mut ptrs: Vec<*const [u8]> = vec![
&array[0..0], &array[0..1], &array, &array[1..]
];
let array_addr = &array as *const [u8] as *const u8 as usize;
let array2_addr = &array2 as *const [u8] as *const u8 as usize;
if array2_addr < array_addr {
ptrs.insert(0, &array2);
} else {
ptrs.push(&array2);
}
assert_inorder(&ptrs, compare_au8);
let u8_ = (0u8, 1u8);
let u32_ = (4u32, 5u32);
// check ordering for ptrs
let buf: &mut [*const dyn Foo] = &mut [
&u8_, &u8_.0,
&u32_, &u32_.0,
];
buf.sort_by(|u,v| {
let u : [*const (); 2] = unsafe { mem::transmute(*u) };
let v : [*const (); 2] = unsafe { mem::transmute(*v) };
u.cmp(&v)
});
assert_inorder(buf, compare_foo);
// check ordering for structs containing arrays
let ss: (S<[u8; 2]>,
S<[u8; 3]>,
S<[u8; 2]>) = (
S(7, [8, 9]),
S(10, [11, 12, 13]),
S(4, [5, 6])
);
assert_inorder(&[
&ss.0 as *const S<[u8]>,
&ss.1 as *const S<[u8]>,
&ss.2 as *const S<[u8]>
], compare_su8);
assert!(simple_eq(&0u8 as *const _, &0u8 as *const _));
assert!(!simple_eq(&0u8 as *const _, &1u8 as *const _));
}
// similar to above, but using &raw
fn main_raw() {
let array = [0,1,2,3,4];
let array2 = [5,6,7,8,9];
// fat ptr comparison: addr then extra
// check ordering for arrays
let mut ptrs: Vec<*const [u8]> = vec![
&raw const array[0..0], &raw const array[0..1], &raw const array, &raw const array[1..]
];
let array_addr = &raw const array as *const u8 as usize;
let array2_addr = &raw const array2 as *const u8 as usize;
if array2_addr < array_addr {
ptrs.insert(0, &raw const array2);
} else {
ptrs.push(&raw const array2);
}
assert_inorder(&ptrs, compare_au8);
let u8_ = (0u8, 1u8);
let u32_ = (4u32, 5u32);
// check ordering for ptrs
let buf: &mut [*const dyn Foo] = &mut [
&raw const u8_, &raw const u8_.0,
&raw const u32_, &raw const u32_.0,
];
buf.sort_by(|u,v| {
let u : [*const (); 2] = unsafe { mem::transmute(*u) };
let v : [*const (); 2] = unsafe { mem::transmute(*v) };
u.cmp(&v)
});
assert_inorder(buf, compare_foo);
// check ordering for structs containing arrays
let ss: (S<[u8; 2]>,
S<[u8; 3]>,
S<[u8; 2]>) = (
S(7, [8, 9]),
S(10, [11, 12, 13]),
S(4, [5, 6])
);
assert_inorder(&[
&raw const ss.0 as *const S<[u8]>,
&raw const ss.1 as *const S<[u8]>,
&raw const ss.2 as *const S<[u8]>
], compare_su8);
}
fn main() {
main_ref();
main_raw();
}
|
