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// This example is interesting because the non-transitive version of `MaybeLiveLocals` would
// report that *all* of these stores are live.
//
//@ needs-unwind
//@ unit-test: DeadStoreElimination-initial
#![feature(core_intrinsics, custom_mir)]
use std::intrinsics::mir::*;
#[inline(never)]
fn cond() -> bool {
false
}
// EMIT_MIR cycle.cycle.DeadStoreElimination-initial.diff
#[custom_mir(dialect = "runtime", phase = "post-cleanup")]
fn cycle(mut x: i32, mut y: i32, mut z: i32) {
// CHECK-LABEL: fn cycle(
// CHECK-NOT: {{_.*}} = {{_.*}};
// CHECK-NOT: {{_.*}} = move {{_.*}};
// We use custom MIR to avoid generating debuginfo, that would force to preserve writes.
mir!(
let condition: bool;
{
Call(condition = cond(), ReturnTo(bb1), UnwindContinue())
}
bb1 = {
match condition { true => bb2, _ => ret }
}
bb2 = {
let temp = z;
z = y;
y = x;
x = temp;
Call(condition = cond(), ReturnTo(bb1), UnwindContinue())
}
ret = {
Return()
}
)
}
fn main() {
cycle(1, 2, 3);
}
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