consolidate ptr tests in fewer files

This commit is contained in:
Ralf Jung 2020-04-16 09:06:21 +02:00
parent 5c823a1ec1
commit b0fe99e81d
7 changed files with 81 additions and 70 deletions

View file

@ -1,6 +0,0 @@
fn main() {
let v = [1i16, 2];
let x = &v as *const [i16] as *const i16;
let x = x.wrapping_offset(1);
assert_eq!(unsafe { *x }, 2);
}

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@ -1,12 +0,0 @@
use std::ptr;
fn main() {
let v = [1i16, 2];
let x = &mut ptr::null(); // going through memory as there are more sanity checks along that path
*x = v.as_ptr().wrapping_offset(1); // ptr to the 2nd element
// Adding 2*isize::max and then 1 is like substracting 1
*x = x.wrapping_offset(isize::MAX);
*x = x.wrapping_offset(isize::MAX);
*x = x.wrapping_offset(1);
assert_eq!(unsafe { **x }, 1);
}

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@ -7,7 +7,7 @@ fn eq_ref<T>(x: &T, y: &T) -> bool {
fn f() -> i32 { 42 }
fn main() {
fn ptr_int_casts() {
// int-ptr-int
assert_eq!(1 as *const i32 as usize, 1);
assert_eq!((1 as *const i32).wrapping_offset(4) as usize, 1 + 4*4);
@ -40,3 +40,29 @@ fn main() {
// involving types other than usize
assert_eq!((-1i32) as usize as *const i32 as usize, (-1i32) as usize);
}
fn ptr_int_ops() {
let v = [1i16, 2];
let x = &v[1] as *const i16 as usize;
// arithmetic
let _y = x + 4;
let _y = 4 + x;
let _y = x - 2;
// bit-operations, covered by alignment
assert_eq!(x & 1, 0);
assert_eq!(x & 0, 0);
assert_eq!(1 & (x+1), 1);
let _y = !1 & x;
let _y = !0 & x;
let _y = x & !1;
// remainder, covered by alignment
assert_eq!(x % 2, 0);
assert_eq!((x+1) % 2, 1);
// remainder with 1 is always 0
assert_eq!(x % 1, 0);
}
fn main() {
ptr_int_casts();
ptr_int_ops();
}

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@ -1,20 +0,0 @@
fn main() {
let v = [1i16, 2];
let x = &v[1] as *const i16 as usize;
// arithmetic
let _y = x + 4;
let _y = 4 + x;
let _y = x - 2;
// bit-operations, covered by alignment
assert_eq!(x & 1, 0);
assert_eq!(x & 0, 0);
assert_eq!(1 & (x+1), 1);
let _y = !1 & x;
let _y = !0 & x;
let _y = x & !1;
// remainder, covered by alignment
assert_eq!(x % 2, 0);
assert_eq!((x+1) % 2, 1);
// remainder with 1 is always 0
assert_eq!(x % 1, 0);
}

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@ -1,6 +1,58 @@
fn f() -> i32 { 42 }
#![feature(ptr_offset_from)]
use std::{mem, ptr};
fn main() {
test_offset_from();
test_vec_into_iter();
ptr_arith_offset();
ptr_arith_offset_overflow();
ptr_offset();
}
fn test_offset_from() { unsafe {
let buf = [0u32; 4];
let x = buf.as_ptr() as *const u8;
let y = x.offset(12);
assert_eq!(y.offset_from(x), 12);
assert_eq!(x.offset_from(y), -12);
assert_eq!((y as *const u32).offset_from(x as *const u32), 12/4);
assert_eq!((x as *const u32).offset_from(y as *const u32), -12/4);
let x = (((x as usize) * 2) / 2) as *const u8;
assert_eq!(y.offset_from(x), 12);
assert_eq!(x.offset_from(y), -12);
} }
// This also internally uses offset_from.
fn test_vec_into_iter() {
let v = Vec::<i32>::new();
let i = v.into_iter();
i.size_hint();
}
fn ptr_arith_offset() {
let v = [1i16, 2];
let x = &v as *const [i16] as *const i16;
let x = x.wrapping_offset(1);
assert_eq!(unsafe { *x }, 2);
}
fn ptr_arith_offset_overflow() {
let v = [1i16, 2];
let x = &mut ptr::null(); // going through memory as there are more sanity checks along that path
*x = v.as_ptr().wrapping_offset(1); // ptr to the 2nd element
// Adding 2*isize::max and then 1 is like substracting 1
*x = x.wrapping_offset(isize::MAX);
*x = x.wrapping_offset(isize::MAX);
*x = x.wrapping_offset(1);
assert_eq!(unsafe { **x }, 1);
}
fn ptr_offset() {
fn f() -> i32 { 42 }
let v = [1i16, 2];
let x = &v as *const [i16; 2] as *const i16;
let x = unsafe { x.offset(1) };
@ -10,7 +62,7 @@ fn main() {
unsafe {
let p = f as fn() -> i32 as usize;
let x = (p as *mut u32).offset(0) as usize;
let f: fn() -> i32 = std::mem::transmute(x);
let f: fn() -> i32 = mem::transmute(x);
assert_eq!(f(), 42);
}
}

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@ -1,29 +0,0 @@
#![feature(ptr_offset_from)]
fn test_raw() { unsafe {
let buf = [0u32; 4];
let x = buf.as_ptr() as *const u8;
let y = x.offset(12);
assert_eq!(y.offset_from(x), 12);
assert_eq!(x.offset_from(y), -12);
assert_eq!((y as *const u32).offset_from(x as *const u32), 12/4);
assert_eq!((x as *const u32).offset_from(y as *const u32), -12/4);
let x = (((x as usize) * 2) / 2) as *const u8;
assert_eq!(y.offset_from(x), 12);
assert_eq!(x.offset_from(y), -12);
} }
// This also internally uses offset_from.
fn test_vec_into_iter() {
let v = Vec::<i32>::new();
let i = v.into_iter();
i.size_hint();
}
fn main() {
test_raw();
test_vec_into_iter();
}