rust/tests/codegen/step_by-overflow-checks.rs

27 lines
661 B
Rust

//@ compile-flags: -O
#![crate_type = "lib"]
use std::iter::StepBy;
use std::slice::Iter;
// The constructor for `StepBy` ensures we can never end up needing to do zero
// checks on denominators, so check that the code isn't emitting panic paths.
// CHECK-LABEL: @step_by_len_std
#[no_mangle]
pub fn step_by_len_std(x: &StepBy<Iter<i32>>) -> usize {
// CHECK-NOT: div_by_zero
// CHECK: udiv
// CHECK-NOT: div_by_zero
x.len()
}
// CHECK-LABEL: @step_by_len_naive
#[no_mangle]
pub fn step_by_len_naive(x: Iter<i32>, step_minus_one: usize) -> usize {
// CHECK: udiv
// CHECK: call{{.+}}div_by_zero
x.len() / (step_minus_one + 1)
}