rust/tests/codegen/cast-optimized.rs

34 lines
716 B
Rust

//@ compile-flags: -O -Z merge-functions=disabled
#![crate_type = "lib"]
// This tests that LLVM can optimize based on the niches in the source or
// destination types for casts.
// CHECK-LABEL: @u32_index
#[no_mangle]
pub fn u32_index(c: u32) -> [bool; 22] {
let mut array = [false; 22];
let index = 32 - c.leading_zeros();
// CHECK: call core::panicking::panic
array[index as usize] = true;
array
}
// CHECK-LABEL: @char_as_u32_index
#[no_mangle]
pub fn char_as_u32_index(c: char) -> [bool; 22] {
let c = c as u32;
let mut array = [false; 22];
let index = 32 - c.leading_zeros();
// CHECK-NOT: call core::panicking::panic
array[index as usize] = true;
array
}