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//@ 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}
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