61 lines
1.8 KiB
Rust
61 lines
1.8 KiB
Rust
use super::MISSING_SPIN_LOOP;
|
|
use clippy_utils::diagnostics::span_lint_and_sugg;
|
|
use clippy_utils::is_no_std_crate;
|
|
use rustc_errors::Applicability;
|
|
use rustc_hir::{Block, Expr, ExprKind};
|
|
use rustc_lint::LateContext;
|
|
use rustc_middle::ty;
|
|
use rustc_span::sym;
|
|
|
|
fn unpack_cond<'tcx>(cond: &'tcx Expr<'tcx>) -> &'tcx Expr<'tcx> {
|
|
match &cond.kind {
|
|
ExprKind::Block(
|
|
Block {
|
|
stmts: [],
|
|
expr: Some(e),
|
|
..
|
|
},
|
|
_,
|
|
)
|
|
| ExprKind::Unary(_, e) => unpack_cond(e),
|
|
ExprKind::Binary(_, l, r) => {
|
|
let l = unpack_cond(l);
|
|
if let ExprKind::MethodCall(..) = l.kind {
|
|
l
|
|
} else {
|
|
unpack_cond(r)
|
|
}
|
|
},
|
|
_ => cond,
|
|
}
|
|
}
|
|
|
|
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, cond: &'tcx Expr<'_>, body: &'tcx Expr<'_>) {
|
|
if let ExprKind::Block(
|
|
Block {
|
|
stmts: [], expr: None, ..
|
|
},
|
|
_,
|
|
) = body.kind
|
|
&& let ExprKind::MethodCall(method, callee, ..) = unpack_cond(cond).kind
|
|
&& [sym::load, sym::compare_exchange, sym::compare_exchange_weak].contains(&method.ident.name)
|
|
&& let ty::Adt(def, _args) = cx.typeck_results().expr_ty(callee).kind()
|
|
&& cx.tcx.is_diagnostic_item(sym::AtomicBool, def.did())
|
|
{
|
|
span_lint_and_sugg(
|
|
cx,
|
|
MISSING_SPIN_LOOP,
|
|
body.span,
|
|
"busy-waiting loop should at least have a spin loop hint",
|
|
"try",
|
|
(if is_no_std_crate(cx) {
|
|
"{ core::hint::spin_loop() }"
|
|
} else {
|
|
"{ std::hint::spin_loop() }"
|
|
})
|
|
.into(),
|
|
Applicability::MachineApplicable,
|
|
);
|
|
}
|
|
}
|