rust/tests/codegen/binary-search-index-no-bound-check.rs
2023-01-11 09:32:08 +00:00

39 lines
1.1 KiB
Rust

// compile-flags: -O
// ignore-debug: the debug assertions get in the way
#![crate_type = "lib"]
// Make sure no bounds checks are emitted when slicing or indexing
// with an index from `binary_search`.
// CHECK-LABEL: @binary_search_index_no_bounds_check
#[no_mangle]
pub fn binary_search_index_no_bounds_check(s: &[u8]) -> u8 {
// CHECK-NOT: panic
// CHECK-NOT: slice_index_len_fail
if let Ok(idx) = s.binary_search(&b'\\') {
s[idx]
} else {
42
}
}
// Similarly, check that `partition_point` is known to return a valid fencepost.
// CHECK-LABEL: @unknown_split
#[no_mangle]
pub fn unknown_split(x: &[i32], i: usize) -> (&[i32], &[i32]) {
// This just makes sure that the subsequent function is looking for the
// absence of something that might actually be there.
// CHECK: call core::panicking::panic
x.split_at(i)
}
// CHECK-LABEL: @partition_point_split_no_bounds_check
#[no_mangle]
pub fn partition_point_split_no_bounds_check(x: &[i32], needle: i32) -> (&[i32], &[i32]) {
// CHECK-NOT: call core::panicking::panic
let i = x.partition_point(|p| p < &needle);
x.split_at(i)
}