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//@ compile-flags: -O
#![crate_type = "lib"]
#![feature(core_intrinsics)]
use std::intrinsics::cold_path;
#[inline(never)]
#[no_mangle]
pub fn path_a() {
println!("path a");
}
#[inline(never)]
#[no_mangle]
pub fn path_b() {
println!("path b");
}
#[inline(never)]
#[no_mangle]
pub fn path_c() {
println!("path c");
}
#[inline(never)]
#[no_mangle]
pub fn path_d() {
println!("path d");
}
#[no_mangle]
pub fn test(x: Option<u32>) {
match x {
Some(0) => path_a(),
Some(1) => {
cold_path();
path_b()
}
Some(2) => path_c(),
Some(3) => {
cold_path();
path_d()
}
_ => path_a(),
}
// CHECK-LABEL: @test(
// CHECK: switch i32 %1, label %bb1 [
// CHECK: i32 0, label %bb6
// CHECK: i32 1, label %bb5
// CHECK: i32 2, label %bb4
// CHECK: i32 3, label %bb3
// CHECK: ], !prof ![[NUM1:[0-9]+]]
}
#[no_mangle]
pub fn test2(x: Option<u32>) {
match x {
Some(10) => path_a(),
Some(11) => {
cold_path();
path_b()
}
Some(12) => {
unsafe { core::intrinsics::unreachable() };
path_c()
}
Some(13) => {
cold_path();
path_d()
}
_ => {
cold_path();
path_a()
}
}
// CHECK-LABEL: @test2(
// CHECK: switch i32 %1, label %bb1 [
// CHECK: i32 10, label %bb5
// CHECK: i32 11, label %bb4
// CHECK: i32 13, label %bb3
// CHECK: ], !prof ![[NUM2:[0-9]+]]
}
// CHECK: ![[NUM1]] = !{!"branch_weights", i32 2000, i32 2000, i32 1, i32 2000, i32 1}
// CHECK: ![[NUM2]] = !{!"branch_weights", i32 1, i32 2000, i32 1, i32 1}
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