Auto merge of #142830 - cjgillot:lower-incr-2, r=<try>

Make lowering incremental, take 3/N

Rebase of #88186 that was rebased by #127262

No real change in design, so I'm not expecting a perf miracle.

r? `@ghost`

Author: bors

compiler/rustc_ast/src/ast.rs

@@ -4033,6 +4033,17 @@ impl TryFrom<ItemKind> for ForeignItemKind {
 
 pub type ForeignItem = Item<ForeignItemKind>;
 
+#[derive(Debug)]
+pub enum AstOwner<'a> {
+    NonOwner,
+    Synthetic(rustc_span::def_id::LocalDefId),
+    Crate(&'a Crate),
+    Item(&'a Item),
+    TraitItem(&'a AssocItem),
+    ImplItem(&'a AssocItem),
+    ForeignItem(&'a ForeignItem),
+}
+
 // Some nodes are used a lot. Make sure they don't unintentionally get bigger.
 #[cfg(target_pointer_width = "64")]
 mod size_asserts {

compiler/rustc_ast_lowering/src/asm.rs

@@ -20,10 +20,10 @@ use super::errors::{
 };
 use crate::{
     AllowReturnTypeNotation, ImplTraitContext, ImplTraitPosition, ParamMode,
-    ResolverAstLoweringExt, fluent_generated as fluent,
+    fluent_generated as fluent,
 };
 
-impl<'a, 'hir> LoweringContext<'a, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     pub(crate) fn lower_inline_asm(
         &mut self,
         sp: Span,
@@ -200,7 +200,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     },
                     InlineAsmOperand::Sym { sym } => {
                         let static_def_id = self
-                            .resolver
                             .get_partial_res(sym.id)
                             .and_then(|res| res.full_res())
                             .and_then(|res| match res {

compiler/rustc_ast_lowering/src/block.rs

@@ -5,7 +5,7 @@ use smallvec::SmallVec;
 
 use crate::{ImplTraitContext, ImplTraitPosition, LoweringContext};
 
-impl<'a, 'hir> LoweringContext<'a, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     pub(super) fn lower_block(
         &mut self,
         b: &Block,

compiler/rustc_ast_lowering/src/delegation.rs

@@ -46,12 +46,14 @@ use rustc_ast::*;
 use rustc_errors::ErrorGuaranteed;
 use rustc_hir::def_id::DefId;
 use rustc_middle::span_bug;
-use rustc_middle::ty::{Asyncness, ResolverAstLowering};
+use rustc_middle::ty::Asyncness;
 use rustc_span::{Ident, Span, Symbol};
 use {rustc_ast as ast, rustc_hir as hir};
 
-use super::{GenericArgsMode, ImplTraitContext, LoweringContext, ParamMode};
-use crate::{AllowReturnTypeNotation, ImplTraitPosition, ResolverAstLoweringExt};
+use super::{
+    AllowReturnTypeNotation, GenericArgsMode, ImplTraitContext, ImplTraitPosition, LoweringContext,
+    ParamMode,
+};
 
 pub(crate) struct DelegationResults<'hir> {
     pub body_id: hir::BodyId,
@@ -60,7 +62,7 @@ pub(crate) struct DelegationResults<'hir> {
     pub generics: &'hir hir::Generics<'hir>,
 }
 
-impl<'hir> LoweringContext<'_, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     /// Defines whether the delegatee is an associated function whose first parameter is `self`.
     pub(crate) fn delegatee_is_method(
         &self,
@@ -125,8 +127,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
     }
 
     fn get_resolution_id(&self, node_id: NodeId, span: Span) -> Result<DefId, ErrorGuaranteed> {
-        let def_id =
-            self.resolver.get_partial_res(node_id).and_then(|r| r.expect_full_res().opt_def_id());
+        let def_id = self.get_partial_res(node_id).and_then(|r| r.expect_full_res().opt_def_id());
         def_id.ok_or_else(|| {
             self.tcx.dcx().span_delayed_bug(
                 span,
@@ -281,7 +282,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     && idx == 0
                 {
                     let mut self_resolver = SelfResolver {
-                        resolver: this.resolver,
+                        ctxt: this,
                         path_id: delegation.id,
                         self_param_id: pat_node_id,
                     };
@@ -427,25 +428,25 @@ impl<'hir> LoweringContext<'_, 'hir> {
     }
 }
 
-struct SelfResolver<'a> {
-    resolver: &'a mut ResolverAstLowering,
+struct SelfResolver<'r, 'hir> {
+    ctxt: &'r mut LoweringContext<'hir>,
     path_id: NodeId,
     self_param_id: NodeId,
 }
 
-impl<'a> SelfResolver<'a> {
+impl SelfResolver<'_, '_> {
     fn try_replace_id(&mut self, id: NodeId) {
-        if let Some(res) = self.resolver.partial_res_map.get(&id)
+        if let Some(res) = self.ctxt.get_partial_res(id)
             && let Some(Res::Local(sig_id)) = res.full_res()
             && sig_id == self.path_id
         {
             let new_res = PartialRes::new(Res::Local(self.self_param_id));
-            self.resolver.partial_res_map.insert(id, new_res);
+            self.ctxt.partial_res_overrides.insert(id, new_res);
         }
     }
 }
 
-impl<'ast, 'a> Visitor<'ast> for SelfResolver<'a> {
+impl<'ast> Visitor<'ast> for SelfResolver<'_, '_> {
     fn visit_id(&mut self, id: NodeId) {
         self.try_replace_id(id);
     }

compiler/rustc_ast_lowering/src/expr.rs

@@ -8,6 +8,7 @@ use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_hir as hir;
 use rustc_hir::HirId;
 use rustc_hir::def::{DefKind, Res};
+use rustc_hir::definitions::DefPathData;
 use rustc_middle::span_bug;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::errors::report_lit_error;
@@ -51,7 +52,7 @@ impl<'v> rustc_ast::visit::Visitor<'v> for WillCreateDefIdsVisitor {
     }
 }
 
-impl<'hir> LoweringContext<'_, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     fn lower_exprs(&mut self, exprs: &[AstP<Expr>]) -> &'hir [hir::Expr<'hir>] {
         self.arena.alloc_from_iter(exprs.iter().map(|x| self.lower_expr_mut(x)))
     }
@@ -491,7 +492,13 @@ impl<'hir> LoweringContext<'_, 'hir> {
         for (idx, arg) in args.iter().cloned().enumerate() {
             if legacy_args_idx.contains(&idx) {
                 let node_id = self.next_node_id();
-                self.create_def(node_id, None, DefKind::AnonConst, f.span);
+                self.create_def(
+                    node_id,
+                    None,
+                    DefKind::AnonConst,
+                    DefPathData::LateAnonConst,
+                    f.span,
+                );
                 let mut visitor = WillCreateDefIdsVisitor {};
                 let const_value = if let ControlFlow::Break(span) = visitor.visit_expr(&arg) {
                     AstP(Expr {
@@ -1263,7 +1270,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         whole_span: Span,
     ) -> hir::ExprKind<'hir> {
         // Return early in case of an ordinary assignment.
-        fn is_ordinary(lower_ctx: &mut LoweringContext<'_, '_>, lhs: &Expr) -> bool {
+        fn is_ordinary(lower_ctx: &mut LoweringContext<'_>, lhs: &Expr) -> bool {
             match &lhs.kind {
                 ExprKind::Array(..)
                 | ExprKind::Struct(..)
@@ -1323,7 +1330,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
     ) -> Option<(&'a Option<AstP<QSelf>>, &'a Path)> {
         if let ExprKind::Path(qself, path) = &expr.kind {
             // Does the path resolve to something disallowed in a tuple struct/variant pattern?
-            if let Some(partial_res) = self.resolver.get_partial_res(expr.id) {
+            if let Some(partial_res) = self.get_partial_res(expr.id) {
                 if let Some(res) = partial_res.full_res()
                     && !res.expected_in_tuple_struct_pat()
                 {
@@ -1345,7 +1352,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
     ) -> Option<(&'a Option<AstP<QSelf>>, &'a Path)> {
         if let ExprKind::Path(qself, path) = &expr.kind {
             // Does the path resolve to something disallowed in a unit struct/variant pattern?
-            if let Some(partial_res) = self.resolver.get_partial_res(expr.id) {
+            if let Some(partial_res) = self.get_partial_res(expr.id) {
                 if let Some(res) = partial_res.full_res()
                     && !res.expected_in_unit_struct_pat()
                 {

compiler/rustc_ast_lowering/src/format.rs

@@ -8,7 +8,7 @@ use rustc_span::{Ident, Span, Symbol, sym};
 
 use super::LoweringContext;
 
-impl<'hir> LoweringContext<'_, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     pub(crate) fn lower_format_args(&mut self, sp: Span, fmt: &FormatArgs) -> hir::ExprKind<'hir> {
         // Never call the const constructor of `fmt::Arguments` if the
         // format_args!() had any arguments _before_ flattening/inlining.
@@ -229,7 +229,7 @@ enum ArgumentType {
 ///     <core::fmt::Argument>::new_…(arg)
 /// ```
 fn make_argument<'hir>(
-    ctx: &mut LoweringContext<'_, 'hir>,
+    ctx: &mut LoweringContext<'hir>,
     sp: Span,
     arg: &'hir hir::Expr<'hir>,
     ty: ArgumentType,
@@ -278,7 +278,7 @@ fn make_argument<'hir>(
 ///     <core::fmt::rt::Count>::Implied
 /// ```
 fn make_count<'hir>(
-    ctx: &mut LoweringContext<'_, 'hir>,
+    ctx: &mut LoweringContext<'hir>,
     sp: Span,
     count: &Option<FormatCount>,
     argmap: &mut FxIndexMap<(usize, ArgumentType), Option<Span>>,
@@ -329,7 +329,7 @@ fn make_count<'hir>(
 ///     }
 /// ```
 fn make_format_spec<'hir>(
-    ctx: &mut LoweringContext<'_, 'hir>,
+    ctx: &mut LoweringContext<'hir>,
     sp: Span,
     placeholder: &FormatPlaceholder,
     argmap: &mut FxIndexMap<(usize, ArgumentType), Option<Span>>,
@@ -390,7 +390,7 @@ fn make_format_spec<'hir>(
 }
 
 fn expand_format_args<'hir>(
-    ctx: &mut LoweringContext<'_, 'hir>,
+    ctx: &mut LoweringContext<'hir>,
     macsp: Span,
     fmt: &FormatArgs,
     allow_const: bool,