1 use rustc_ast::Attribute;
3 use rustc_hir::def_id::LocalDefId;
4 use rustc_hir::itemlikevisit::ItemLikeVisitor;
5 use rustc_hir::ItemKind;
6 use rustc_middle::ty::layout::{HasParamEnv, HasTyCtxt, LayoutError, LayoutOfHelpers, TyAndLayout};
7 use rustc_middle::ty::{ParamEnv, Ty, TyCtxt};
8 use rustc_span::symbol::sym;
10 use rustc_target::abi::{HasDataLayout, TargetDataLayout};
12 pub fn test_layout(tcx: TyCtxt<'_>) {
13 if tcx.features().rustc_attrs {
14 // if the `rustc_attrs` feature is not enabled, don't bother testing layout
15 tcx.hir().krate().visit_all_item_likes(&mut LayoutTest { tcx });
19 struct LayoutTest<'tcx> {
23 impl ItemLikeVisitor<'tcx> for LayoutTest<'tcx> {
24 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
28 | ItemKind::Struct(..)
29 | ItemKind::Union(..) => {
30 for attr in self.tcx.get_attrs(item.def_id.to_def_id()).iter() {
31 if attr.has_name(sym::rustc_layout) {
32 self.dump_layout_of(item.def_id, item, attr);
40 fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) {}
41 fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem<'tcx>) {}
42 fn visit_foreign_item(&mut self, _: &'tcx hir::ForeignItem<'tcx>) {}
45 impl LayoutTest<'tcx> {
46 fn dump_layout_of(&self, item_def_id: LocalDefId, item: &hir::Item<'tcx>, attr: &Attribute) {
48 let param_env = self.tcx.param_env(item_def_id);
49 let ty = self.tcx.type_of(item_def_id);
50 match self.tcx.layout_of(param_env.and(ty)) {
52 // Check out the `#[rustc_layout(..)]` attribute to tell what to dump.
53 // The `..` are the names of fields to dump.
54 let meta_items = attr.meta_item_list().unwrap_or_default();
55 for meta_item in meta_items {
56 match meta_item.name_or_empty() {
58 self.tcx.sess.span_err(item.span, &format!("abi: {:?}", ty_layout.abi));
64 .span_err(item.span, &format!("align: {:?}", ty_layout.align));
70 .span_err(item.span, &format!("size: {:?}", ty_layout.size));
73 sym::homogeneous_aggregate => {
74 self.tcx.sess.span_err(
77 "homogeneous_aggregate: {:?}",
79 .homogeneous_aggregate(&UnwrapLayoutCx { tcx, param_env }),
85 let normalized_ty = self.tcx.normalize_erasing_regions(
86 param_env.with_reveal_all_normalized(self.tcx),
89 self.tcx.sess.span_err(
91 &format!("layout_of({:?}) = {:#?}", normalized_ty, *ty_layout),
96 self.tcx.sess.span_err(
98 &format!("unrecognized field name `{}`", name),
105 Err(layout_error) => {
106 self.tcx.sess.span_err(item.span, &format!("layout error: {:?}", layout_error));
112 struct UnwrapLayoutCx<'tcx> {
114 param_env: ParamEnv<'tcx>,
117 impl LayoutOfHelpers<'tcx> for UnwrapLayoutCx<'tcx> {
118 type LayoutOfResult = TyAndLayout<'tcx>;
120 fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
123 "`#[rustc_layout(..)]` test resulted in `layout_of({}) = Err({})`",
130 impl HasTyCtxt<'tcx> for UnwrapLayoutCx<'tcx> {
131 fn tcx(&self) -> TyCtxt<'tcx> {
136 impl HasParamEnv<'tcx> for UnwrapLayoutCx<'tcx> {
137 fn param_env(&self) -> ParamEnv<'tcx> {
142 impl HasDataLayout for UnwrapLayoutCx<'tcx> {
143 fn data_layout(&self) -> &TargetDataLayout {
144 self.tcx.data_layout()