rust/tests/codegen/box-maybe-uninit.rs
Pietro Albini 292bc548c8
codegen: do not require the uwtables attribute
The attribute is not emitted on targets without unwinding tables.
2023-05-23 16:54:34 +02:00

34 lines
1.2 KiB
Rust

// compile-flags: -O
// min-llvm-version: 15.0
#![crate_type = "lib"]
use std::mem::MaybeUninit;
// Boxing a `MaybeUninit` value should not copy junk from the stack
#[no_mangle]
pub fn box_uninitialized() -> Box<MaybeUninit<usize>> {
// CHECK-LABEL: @box_uninitialized
// CHECK-NOT: store
// CHECK-NOT: alloca
// CHECK-NOT: memcpy
// CHECK-NOT: memset
Box::new(MaybeUninit::uninit())
}
// https://github.com/rust-lang/rust/issues/58201
#[no_mangle]
pub fn box_uninitialized2() -> Box<MaybeUninit<[usize; 1024 * 1024]>> {
// CHECK-LABEL: @box_uninitialized2
// CHECK-NOT: store
// CHECK-NOT: alloca
// CHECK-NOT: memcpy
// CHECK-NOT: memset
Box::new(MaybeUninit::uninit())
}
// Hide the `allocalign` attribute in the declaration of __rust_alloc
// from the CHECK-NOT above, and also verify the attributes got set reasonably.
// CHECK: declare {{(dso_local )?}}noalias noundef ptr @__rust_alloc(i{{[0-9]+}} noundef, i{{[0-9]+}} allocalign noundef) unnamed_addr [[RUST_ALLOC_ATTRS:#[0-9]+]]
// CHECK-DAG: attributes [[RUST_ALLOC_ATTRS]] = { {{.*}} allockind("alloc,uninitialized,aligned") allocsize(0) {{(uwtable )?}}"alloc-family"="__rust_alloc" {{.*}} }