Revert "Introduce lowering_arena to avoid creating AST nodes on the fly"

This reverts commit d9a1faaa9c.

This was originally part of a larger PR that has now been closed as a
different approach is taken now.
This commit is contained in:
Nilstrieb 2022-12-18 20:28:59 +01:00
parent 37efc81072
commit d59a2ac2bc
2 changed files with 21 additions and 38 deletions

View File

@ -1,6 +1,6 @@
use super::errors::{InvalidAbi, InvalidAbiSuggestion, MisplacedRelaxTraitBound};
use super::ResolverAstLoweringExt;
use super::{Arena, AstOwner, ImplTraitContext, ImplTraitPosition};
use super::{AstOwner, ImplTraitContext, ImplTraitPosition};
use super::{FnDeclKind, LoweringContext, ParamMode};
use rustc_ast::ptr::P;
@ -24,7 +24,6 @@ use thin_vec::ThinVec;
pub(super) struct ItemLowerer<'a, 'hir> {
pub(super) tcx: TyCtxt<'hir>,
pub(super) resolver: &'a mut ResolverAstLowering,
pub(super) ast_arena: &'a Arena<'static>,
pub(super) ast_index: &'a IndexVec<LocalDefId, AstOwner<'a>>,
pub(super) owners: &'a mut IndexVec<LocalDefId, hir::MaybeOwner<&'hir hir::OwnerInfo<'hir>>>,
}
@ -60,7 +59,6 @@ impl<'a, 'hir> ItemLowerer<'a, 'hir> {
tcx: self.tcx,
resolver: self.resolver,
arena: self.tcx.hir_arena,
ast_arena: self.ast_arena,
// HirId handling.
bodies: Vec::new(),

View File

@ -42,7 +42,6 @@ extern crate tracing;
use crate::errors::{AssocTyParentheses, AssocTyParenthesesSub, MisplacedImplTrait, TraitFnAsync};
use rustc_arena::declare_arena;
use rustc_ast::ptr::P;
use rustc_ast::visit;
use rustc_ast::{self as ast, *};
@ -94,13 +93,6 @@ struct LoweringContext<'a, 'hir> {
/// Used to allocate HIR nodes.
arena: &'hir hir::Arena<'hir>,
/// Used to allocate temporary AST nodes for use during lowering.
/// This allows us to create "fake" AST -- these nodes can sometimes
/// be allocated on the stack, but other times we need them to live longer
/// than the current stack frame, so they can be collected into vectors
/// and things like that.
ast_arena: &'a Arena<'static>,
/// Bodies inside the owner being lowered.
bodies: Vec<(hir::ItemLocalId, &'hir hir::Body<'hir>)>,
/// Attributes inside the owner being lowered.
@ -146,15 +138,6 @@ struct LoweringContext<'a, 'hir> {
generics_def_id_map: Vec<FxHashMap<LocalDefId, LocalDefId>>,
}
declare_arena!([
[] tys: rustc_ast::Ty,
[] aba: rustc_ast::AngleBracketedArgs,
[] ptr: rustc_ast::PolyTraitRef,
// This _marker field is needed because `declare_arena` creates `Arena<'tcx>` and we need to
// use `'tcx`. If we don't have this we get a compile error.
[] _marker: std::marker::PhantomData<&'tcx ()>,
]);
trait ResolverAstLoweringExt {
fn legacy_const_generic_args(&self, expr: &Expr) -> Option<Vec<usize>>;
fn get_partial_res(&self, id: NodeId) -> Option<PartialRes>;
@ -442,13 +425,10 @@ pub fn lower_to_hir<'hir>(tcx: TyCtxt<'hir>, (): ()) -> hir::Crate<'hir> {
tcx.definitions_untracked().def_index_count(),
);
let ast_arena = Arena::default();
for def_id in ast_index.indices() {
item::ItemLowerer {
tcx,
resolver: &mut resolver,
ast_arena: &ast_arena,
ast_index: &ast_index,
owners: &mut owners,
}
@ -1001,8 +981,12 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
}
GenericArgs::Parenthesized(data) => {
self.emit_bad_parenthesized_trait_in_assoc_ty(data);
let aba = self.ast_arena.aba.alloc(data.as_angle_bracketed_args());
self.lower_angle_bracketed_parameter_data(aba, ParamMode::Explicit, itctx).0
self.lower_angle_bracketed_parameter_data(
&data.as_angle_bracketed_args(),
ParamMode::Explicit,
itctx,
)
.0
}
};
gen_args_ctor.into_generic_args(self)
@ -1067,13 +1051,15 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
self.with_dyn_type_scope(false, |this| {
let node_id = this.next_node_id();
let ty = this.ast_arena.tys.alloc(Ty {
id: node_id,
kind: TyKind::ImplTrait(impl_trait_node_id, bounds.clone()),
span: this.lower_span(constraint.span),
tokens: None,
});
let ty = this.lower_ty(ty, itctx);
let ty = this.lower_ty(
&Ty {
id: node_id,
kind: TyKind::ImplTrait(impl_trait_node_id, bounds.clone()),
span: this.lower_span(constraint.span),
tokens: None,
},
itctx,
);
hir::TypeBindingKind::Equality { term: ty.into() }
})
@ -1217,13 +1203,12 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
&& let Some(Res::Def(DefKind::Trait | DefKind::TraitAlias, _)) = partial_res.full_res()
{
let (bounds, lifetime_bound) = self.with_dyn_type_scope(true, |this| {
let poly_trait_ref = this.ast_arena.ptr.alloc(PolyTraitRef {
bound_generic_params: vec![],
trait_ref: TraitRef { path: path.clone(), ref_id: t.id },
span: t.span
});
let bound = this.lower_poly_trait_ref(
poly_trait_ref,
&PolyTraitRef {
bound_generic_params: vec![],
trait_ref: TraitRef { path: path.clone(), ref_id: t.id },
span: t.span
},
itctx,
);
let bounds = this.arena.alloc_from_iter([bound]);