mirror of https://github.com/rust-lang/rust
24 lines
534 B
Rust
24 lines
534 B
Rust
#[no_mangle]
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pub fn cold_function(c: u8) {
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println!("cold {}", c);
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}
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#[no_mangle]
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pub fn hot_function(c: u8) {
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std::env::set_var(format!("var{}", c), format!("hot {}", c));
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}
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fn main() {
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let arg = std::env::args().skip(1).next().unwrap();
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for i in 0..1000_000 {
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let some_value = arg.as_bytes()[i % arg.len()];
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if some_value == b'!' {
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// This branch is never taken at runtime
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cold_function(some_value);
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} else {
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hot_function(some_value);
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}
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}
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}
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