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// no-system-llvm
// compile-flags: -O
// ignore-debug: the debug assertions get in the way
#![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];
}
}
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