Invoke `trait_def` query only once

This may be a small performance boost as we have to hash less to lookup the value
This commit is contained in:
Oli Scherer 2024-02-13 09:29:31 +00:00
parent 11a73f6d4d
commit 55bbb054c9
2 changed files with 13 additions and 10 deletions

View File

@ -23,6 +23,7 @@ fn check_impl(
tcx: TyCtxt<'_>,
impl_def_id: LocalDefId,
trait_ref: ty::TraitRef<'_>,
trait_def: &ty::TraitDef,
) -> Result<(), ErrorGuaranteed> {
debug!(
"(checking implementation) adding impl for trait '{:?}', item '{}'",
@ -36,19 +37,20 @@ fn check_impl(
return Ok(());
}
enforce_trait_manually_implementable(tcx, impl_def_id, trait_ref.def_id)
.and(enforce_empty_impls_for_marker_traits(tcx, impl_def_id, trait_ref.def_id))
enforce_trait_manually_implementable(tcx, impl_def_id, trait_ref.def_id, trait_def)
.and(enforce_empty_impls_for_marker_traits(tcx, impl_def_id, trait_ref.def_id, trait_def))
}
fn enforce_trait_manually_implementable(
tcx: TyCtxt<'_>,
impl_def_id: LocalDefId,
trait_def_id: DefId,
trait_def: &ty::TraitDef,
) -> Result<(), ErrorGuaranteed> {
let impl_header_span = tcx.def_span(impl_def_id);
// Disallow *all* explicit impls of traits marked `#[rustc_deny_explicit_impl]`
if tcx.trait_def(trait_def_id).deny_explicit_impl {
if trait_def.deny_explicit_impl {
let trait_name = tcx.item_name(trait_def_id);
let mut err = struct_span_code_err!(
tcx.dcx(),
@ -67,8 +69,7 @@ fn enforce_trait_manually_implementable(
return Err(err.emit());
}
if let ty::trait_def::TraitSpecializationKind::AlwaysApplicable =
tcx.trait_def(trait_def_id).specialization_kind
if let ty::trait_def::TraitSpecializationKind::AlwaysApplicable = trait_def.specialization_kind
{
if !tcx.features().specialization
&& !tcx.features().min_specialization
@ -87,8 +88,9 @@ fn enforce_empty_impls_for_marker_traits(
tcx: TyCtxt<'_>,
impl_def_id: LocalDefId,
trait_def_id: DefId,
trait_def: &ty::TraitDef,
) -> Result<(), ErrorGuaranteed> {
if !tcx.trait_def(trait_def_id).is_marker {
if !trait_def.is_marker {
return Ok(());
}
@ -133,11 +135,12 @@ fn coherent_trait(tcx: TyCtxt<'_>, def_id: DefId) -> Result<(), ErrorGuaranteed>
for &impl_def_id in impls {
let trait_header = tcx.impl_trait_header(impl_def_id).unwrap().instantiate_identity();
let trait_def = tcx.trait_def(trait_header.trait_ref.def_id);
res = res.and(check_impl(tcx, impl_def_id, trait_header.trait_ref));
res = res.and(check_impl(tcx, impl_def_id, trait_header.trait_ref, trait_def));
res = res.and(check_object_overlap(tcx, impl_def_id, trait_header.trait_ref));
res = res.and(unsafety::check_item(tcx, impl_def_id, trait_header));
res = res.and(unsafety::check_item(tcx, impl_def_id, trait_header, trait_def));
res = res.and(tcx.ensure().orphan_check_impl(impl_def_id));
res = res.and(builtin::check_trait(tcx, def_id, impl_def_id));
}

View File

@ -3,7 +3,7 @@
use rustc_errors::{codes::*, struct_span_code_err};
use rustc_hir::Unsafety;
use rustc_middle::ty::{ImplPolarity::*, ImplTraitHeader, TyCtxt};
use rustc_middle::ty::{ImplPolarity::*, ImplTraitHeader, TraitDef, TyCtxt};
use rustc_span::def_id::LocalDefId;
use rustc_span::ErrorGuaranteed;
@ -11,9 +11,9 @@ pub(super) fn check_item(
tcx: TyCtxt<'_>,
def_id: LocalDefId,
trait_header: ImplTraitHeader<'_>,
trait_def: &TraitDef,
) -> Result<(), ErrorGuaranteed> {
let trait_ref = trait_header.trait_ref;
let trait_def = tcx.trait_def(trait_ref.def_id);
let unsafe_attr =
tcx.generics_of(def_id).params.iter().find(|p| p.pure_wrt_drop).map(|_| "may_dangle");
match (trait_def.unsafety, unsafe_attr, trait_header.unsafety, trait_header.polarity) {