| //@ compile-flags: -Copt-level=3 |
| #![crate_type = "lib"] |
| |
| // Check that no panic is generated in `split_at` when calculating the index for |
| // the tail chunk using `checked_sub`. |
| // |
| // Tests written for refactored implementations of: |
| // `<[T]>::{split_last_chunk, split_last_chunk_mut, last_chunk, last_chunk_mut}` |
| |
| // CHECK-LABEL: @split_at_last_chunk |
| #[no_mangle] |
| pub fn split_at_last_chunk(s: &[u8], chunk_size: usize) -> Option<(&[u8], &[u8])> { |
| // CHECK-NOT: panic |
| let Some(index) = s.len().checked_sub(chunk_size) else { return None }; |
| Some(s.split_at(index)) |
| } |
| |
| // CHECK-LABEL: @split_at_mut_last_chunk |
| #[no_mangle] |
| pub fn split_at_mut_last_chunk(s: &mut [u8], chunk_size: usize) -> Option<(&mut [u8], &mut [u8])> { |
| // CHECK-NOT: panic |
| let Some(index) = s.len().checked_sub(chunk_size) else { return None }; |
| Some(s.split_at_mut(index)) |
| } |
