| //@ compile-flags: -O |
| #![crate_type = "lib"] |
| |
| // Make sure no bounds checks are emitted in the loop when upfront slicing |
| // ensures that the slices are big enough. |
| // In particular, bounds checks were not always optimized out if the upfront |
| // check was for a greater len than the loop requires. |
| // (i.e. `already_sliced_no_bounds_check` was not always optimized even when |
| // `already_sliced_no_bounds_check_exact` was) |
| // CHECK-LABEL: @already_sliced_no_bounds_check |
| #[no_mangle] |
| pub fn already_sliced_no_bounds_check(a: &[u8], b: &[u8], c: &mut [u8]) { |
| // CHECK: slice_end_index_len_fail |
| // CHECK-NOT: panic_bounds_check |
| let _ = (&a[..2048], &b[..2048], &mut c[..2048]); |
| for i in 0..1024 { |
| c[i] = a[i] ^ b[i]; |
| } |
| } |
| |
| // CHECK-LABEL: @already_sliced_no_bounds_check_exact |
| #[no_mangle] |
| pub fn already_sliced_no_bounds_check_exact(a: &[u8], b: &[u8], c: &mut [u8]) { |
| // CHECK: slice_end_index_len_fail |
| // CHECK-NOT: panic_bounds_check |
| let _ = (&a[..1024], &b[..1024], &mut c[..1024]); |
| for i in 0..1024 { |
| c[i] = a[i] ^ b[i]; |
| } |
| } |
| |
| // Make sure we're checking for the right thing: there can be a panic if the slice is too small. |
| // CHECK-LABEL: @already_sliced_bounds_check |
| #[no_mangle] |
| pub fn already_sliced_bounds_check(a: &[u8], b: &[u8], c: &mut [u8]) { |
| // CHECK: slice_end_index_len_fail |
| // CHECK: panic_bounds_check |
| let _ = (&a[..1023], &b[..2048], &mut c[..2048]); |
| for i in 0..1024 { |
| c[i] = a[i] ^ b[i]; |
| } |
| } |
