mirror of
https://github.com/rust-lang/rust.git
synced 2024-10-30 14:01:51 +00:00
72800d3b89
Except for `simd-intrinsic/`, which has a lot of files containing multiple types like `u8x64` which really are better when hand-formatted. There is a surprising amount of two-space indenting in this directory. Non-trivial changes: - `rustfmt::skip` needed in `debug-column.rs` to preserve meaning of the test. - `rustfmt::skip` used in a few places where hand-formatting read more nicely: `enum/enum-match.rs` - Line number adjustments needed for the expected output of `debug-column.rs` and `coroutine-debug.rs`.
76 lines
2.6 KiB
Rust
76 lines
2.6 KiB
Rust
//@ compile-flags: -O
|
|
|
|
#![crate_type = "lib"]
|
|
|
|
// CHECK-LABEL: @align8
|
|
#[no_mangle]
|
|
pub fn align8(p: *const u8) -> bool {
|
|
// CHECK: ret i1 true
|
|
p.align_offset(8) < 8
|
|
}
|
|
|
|
#[repr(align(4))]
|
|
pub struct Align4([u8; 4]);
|
|
|
|
// CHECK-LABEL: @align_to4
|
|
#[no_mangle]
|
|
pub fn align_to4(x: &[u8]) -> bool {
|
|
// CHECK: ret i1 true
|
|
let (prefix, _middle, suffix) = unsafe { x.align_to::<Align4>() };
|
|
prefix.len() < 4 && suffix.len() < 4
|
|
}
|
|
|
|
// CHECK-LABEL: @align_offset_byte_ptr(ptr{{.+}}%ptr)
|
|
#[no_mangle]
|
|
pub fn align_offset_byte_ptr(ptr: *const u8) -> usize {
|
|
// CHECK: %[[ADDR:.+]] = ptrtoint ptr %ptr to [[USIZE:i[0-9]+]]
|
|
// CHECK: %[[UP:.+]] = add [[USIZE]] %[[ADDR]], 31
|
|
// CHECK: %[[ALIGNED:.+]] = and [[USIZE]] %[[UP]], -32
|
|
// CHECK: %[[OFFSET:.+]] = sub [[USIZE]] %[[ALIGNED]], %[[ADDR]]
|
|
|
|
// Since we're offsetting a byte pointer, there's no further fixups
|
|
// CHECK-NOT: shr
|
|
// CHECK-NOT: div
|
|
// CHECK-NOT: select
|
|
|
|
// CHECK: ret [[USIZE]] %[[OFFSET]]
|
|
ptr.align_offset(32)
|
|
}
|
|
|
|
// CHECK-LABEL: @align_offset_word_slice(ptr{{.+}}align 4{{.+}}%slice.0
|
|
#[no_mangle]
|
|
pub fn align_offset_word_slice(slice: &[Align4]) -> usize {
|
|
// CHECK: %[[ADDR:.+]] = ptrtoint ptr %slice.0 to [[USIZE]]
|
|
// CHECK: %[[UP:.+]] = add [[USIZE]] %[[ADDR]], 31
|
|
// CHECK: %[[ALIGNED:.+]] = and [[USIZE]] %[[UP]], -32
|
|
// CHECK: %[[BOFFSET:.+]] = sub [[USIZE]] %[[ALIGNED]], %[[ADDR]]
|
|
// CHECK: %[[OFFSET:.+]] = lshr exact [[USIZE]] %[[BOFFSET]], 2
|
|
|
|
// Slices are known to be aligned, so we don't need the "maybe -1" path
|
|
// CHECK-NOT: select
|
|
|
|
// CHECK: ret [[USIZE]] %[[OFFSET]]
|
|
slice.as_ptr().align_offset(32)
|
|
}
|
|
|
|
// CHECK-LABEL: @align_offset_word_ptr(ptr{{.+}}%ptr
|
|
#[no_mangle]
|
|
pub fn align_offset_word_ptr(ptr: *const Align4) -> usize {
|
|
// CHECK: %[[ADDR:.+]] = ptrtoint ptr %ptr to [[USIZE]]
|
|
// CHECK: %[[UP:.+]] = add [[USIZE]] %[[ADDR]], 31
|
|
// CHECK: %[[ALIGNED:.+]] = and [[USIZE]] %[[UP]], -32
|
|
// CHECK: %[[BOFFSET:.+]] = sub [[USIZE]] %[[ALIGNED]], %[[ADDR]]
|
|
|
|
// While we can always get a *byte* offset that will work, if the original
|
|
// pointer is unaligned it might be impossible to return an *element* offset
|
|
// that will make it aligned. We want it to be a `select`, not a `br`, so
|
|
// that the assembly will be branchless.
|
|
// CHECK: %[[LOW:.+]] = and [[USIZE]] %[[ADDR]], 3
|
|
// CHECK: %[[ORIGINAL_ALIGNED:.+]] = icmp eq [[USIZE]] %[[LOW]], 0
|
|
// CHECK: %[[OFFSET:.+]] = lshr exact [[USIZE]] %[[BOFFSET]], 2
|
|
// CHECK: %[[R:.+]] = select i1 %[[ORIGINAL_ALIGNED]], [[USIZE]] %[[OFFSET]], [[USIZE]] -1
|
|
|
|
// CHECK: ret [[USIZE]] %[[R]]
|
|
ptr.align_offset(32)
|
|
}
|