rust/tests/codegen-llvm/addr-of-mutate.rs
Nikita Popov c3ab409b4f Use captures(address) instead of captures(none) for indirect args
While provenance cannot be captured through these arguments, the
address / object identity can.
2025-08-26 16:16:23 +02:00

34 lines
1.3 KiB
Rust

//@ compile-flags: -C opt-level=3 -C no-prepopulate-passes
#![crate_type = "lib"]
// Test for the absence of `readonly` on the argument when it is mutated via `&raw const`.
// See <https://github.com/rust-lang/rust/issues/111502>.
// CHECK: i8 @foo(ptr{{( dead_on_return)?}} noalias noundef align 1{{( captures\(address\))?}} dereferenceable(128) %x)
#[no_mangle]
pub fn foo(x: [u8; 128]) -> u8 {
let ptr = core::ptr::addr_of!(x).cast_mut();
unsafe {
(*ptr)[0] = 1;
}
x[0]
}
// CHECK: i1 @second(ptr{{( dead_on_return)?}} noalias noundef align {{[0-9]+}}{{( captures\(address\))?}} dereferenceable({{[0-9]+}}) %a_ptr_and_b)
#[no_mangle]
pub unsafe fn second(a_ptr_and_b: (*mut (i32, bool), (i64, bool))) -> bool {
let b_bool_ptr = core::ptr::addr_of!(a_ptr_and_b.1.1).cast_mut();
(*b_bool_ptr) = true;
a_ptr_and_b.1.1
}
// If going through a deref (and there are no other mutating accesses), then `readonly` is fine.
// CHECK: i1 @third(ptr{{( dead_on_return)?}} noalias noundef readonly align {{[0-9]+}}{{( captures\(address\))?}} dereferenceable({{[0-9]+}}) %a_ptr_and_b)
#[no_mangle]
pub unsafe fn third(a_ptr_and_b: (*mut (i32, bool), (i64, bool))) -> bool {
let b_bool_ptr = core::ptr::addr_of!((*a_ptr_and_b.0).1).cast_mut();
(*b_bool_ptr) = true;
a_ptr_and_b.1.1
}