mirror of
https://github.com/rust-lang/rust.git
synced 2025-10-31 04:57:19 +00:00
81 lines
1.5 KiB
Rust
81 lines
1.5 KiB
Rust
//@ compile-flags: -Copt-level=3
|
|
#![crate_type = "lib"]
|
|
#![feature(likely_unlikely)]
|
|
|
|
use std::hint::unlikely;
|
|
|
|
#[inline(never)]
|
|
#[no_mangle]
|
|
pub fn path_a() {
|
|
println!("path a");
|
|
}
|
|
|
|
#[inline(never)]
|
|
#[no_mangle]
|
|
pub fn path_b() {
|
|
println!("path b");
|
|
}
|
|
|
|
#[no_mangle]
|
|
pub fn test1(x: bool) {
|
|
if unlikely(x) {
|
|
path_a();
|
|
} else {
|
|
path_b();
|
|
}
|
|
|
|
// CHECK-LABEL: @test1(
|
|
// CHECK: br i1 %x, label %bb2, label %bb4, !prof ![[NUM:[0-9]+]]
|
|
// CHECK: bb4:
|
|
// CHECK: path_b
|
|
// CHECK: bb2:
|
|
// CHECK: path_a
|
|
}
|
|
|
|
#[no_mangle]
|
|
pub fn test2(x: i32) {
|
|
match unlikely(x > 0) {
|
|
true => path_a(),
|
|
false => path_b(),
|
|
}
|
|
|
|
// CHECK-LABEL: @test2(
|
|
// CHECK: br i1 %_2, label %bb2, label %bb4, !prof ![[NUM]]
|
|
// CHECK: bb4:
|
|
// CHECK: path_b
|
|
// CHECK: bb2:
|
|
// CHECK: path_a
|
|
}
|
|
|
|
#[no_mangle]
|
|
pub fn test3(x: i8) {
|
|
match unlikely(x < 7) {
|
|
true => path_a(),
|
|
_ => path_b(),
|
|
}
|
|
|
|
// CHECK-LABEL: @test3(
|
|
// CHECK: br i1 %_2, label %bb2, label %bb4, !prof ![[NUM]]
|
|
// CHECK: bb4:
|
|
// CHECK: path_b
|
|
// CHECK: bb2:
|
|
// CHECK: path_a
|
|
}
|
|
|
|
#[no_mangle]
|
|
pub fn test4(x: u64) {
|
|
match unlikely(x != 33) {
|
|
false => path_a(),
|
|
_ => path_b(),
|
|
}
|
|
|
|
// CHECK-LABEL: @test4(
|
|
// CHECK: br i1 %0, label %bb4, label %bb2, !prof ![[NUM2:[0-9]+]]
|
|
// CHECK: bb4:
|
|
// CHECK: path_a
|
|
// CHECK: bb2:
|
|
// CHECK: path_b
|
|
}
|
|
|
|
// CHECK: ![[NUM]] = !{!"branch_weights", {{(!"expected", )?}}i32 1, i32 2000}
|