79 lines
1.6 KiB
Rust
79 lines
1.6 KiB
Rust
|
// `SetDiscriminant` does not actually write anything if the chosen variant is the untagged variant
|
||
|
|
// of a niche encoding. Verify that we do not thread over this case.
|
||
|
|
// unit-test: JumpThreading
|
||
|
|
|
||
|
|
#![feature(custom_mir)]
|
||
|
|
#![feature(core_intrinsics)]
|
||
|
|
|
||
|
|
use std::intrinsics::mir::*;
|
||
|
|
|
||
|
|
enum E<T> {
|
||
|
|
A,
|
||
|
|
B(T),
|
||
|
|
}
|
||
|
|
|
||
|
|
// EMIT_MIR set_no_discriminant.f.JumpThreading.diff
|
||
|
|
#[custom_mir(dialect = "runtime")]
|
||
|
|
pub fn f() -> usize {
|
||
|
|
// CHECK-LABEL: fn f(
|
||
|
|
// CHECK-NOT: goto
|
||
|
|
// CHECK: switchInt(
|
||
|
|
// CHECK-NOT: goto
|
||
|
|
mir!(
|
||
|
|
let a: isize;
|
||
|
|
let e: E<char>;
|
||
|
|
{
|
||
|
|
e = E::A;
|
||
|
|
SetDiscriminant(e, 1);
|
||
|
|
a = Discriminant(e);
|
||
|
|
match a {
|
||
|
|
0 => bb0,
|
||
|
|
_ => bb1,
|
||
|
|
}
|
||
|
|
}
|
||
|
|
bb0 = {
|
||
|
|
RET = 0;
|
||
|
|
Return()
|
||
|
|
}
|
||
|
|
bb1 = {
|
||
|
|
RET = 1;
|
||
|
|
Return()
|
||
|
|
}
|
||
|
|
)
|
||
|
|
}
|
||
|
|
|
||
|
|
// EMIT_MIR set_no_discriminant.generic.JumpThreading.diff
|
||
|
|
#[custom_mir(dialect = "runtime")]
|
||
|
|
pub fn generic<T>() -> usize {
|
||
|
|
// CHECK-LABEL: fn generic(
|
||
|
|
// CHECK-NOT: goto
|
||
|
|
// CHECK: switchInt(
|
||
|
|
// CHECK-NOT: goto
|
||
|
|
mir!(
|
||
|
|
let a: isize;
|
||
|
|
let e: E<T>;
|
||
|
|
{
|
||
|
|
e = E::A;
|
||
|
|
SetDiscriminant(e, 1);
|
||
|
|
a = Discriminant(e);
|
||
|
|
match a {
|
||
|
|
0 => bb0,
|
||
|
|
_ => bb1,
|
||
|
|
}
|
||
|
|
}
|
||
|
|
bb0 = {
|
||
|
|
RET = 0;
|
||
|
|
Return()
|
||
|
|
}
|
||
|
|
bb1 = {
|
||
|
|
RET = 1;
|
||
|
|
Return()
|
||
|
|
}
|
||
|
|
)
|
||
|
|
}
|
||
|
|
|
||
|
|
fn main() {
|
||
|
|
assert_eq!(f(), 0);
|
||
|
|
assert_eq!(generic::<char>(), 0);
|
||
|
|
}
|