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

Cargo.lock

@@ -3355,7 +3355,6 @@ version = "0.0.0"
 dependencies = [
  "rustc_abi",
  "rustc_ast",
- "rustc_ast_pretty",
  "rustc_attr_data_structures",
  "rustc_attr_parsing",
  "rustc_data_structures",

compiler/rustc_ast/src/ast.rs

@@ -4054,6 +4054,17 @@ impl TryFrom<ItemKind> for ForeignItemKind {
 
 pub type ForeignItem = Item<ForeignItemKind>;
 
+#[derive(Debug)]
+pub enum AstOwner {
+    NonOwner,
+    Synthetic(rustc_span::def_id::LocalDefId),
+    Crate(P<Crate>),
+    Item(P<Item>),
+    TraitItem(P<AssocItem>),
+    ImplItem(P<AssocItem>),
+    ForeignItem(P<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/src/mut_visit.rs

@@ -142,7 +142,10 @@ pub fn walk_flat_map_stmt<T: MutVisitor>(
     stmts
 }
 
-fn walk_flat_map_stmt_kind<T: MutVisitor>(vis: &mut T, kind: StmtKind) -> SmallVec<[StmtKind; 1]> {
+pub fn walk_flat_map_stmt_kind<T: MutVisitor>(
+    vis: &mut T,
+    kind: StmtKind,
+) -> SmallVec<[StmtKind; 1]> {
     match kind {
         StmtKind::Let(mut local) => smallvec![StmtKind::Let({
             vis.visit_local(&mut local);

compiler/rustc_ast_lowering/Cargo.toml

@@ -10,7 +10,6 @@ doctest = false
 # tidy-alphabetical-start
 rustc_abi = { path = "../rustc_abi" }
 rustc_ast = { path = "../rustc_ast" }
-rustc_ast_pretty = { path = "../rustc_ast_pretty" }
 rustc_attr_data_structures = { path = "../rustc_attr_data_structures" }
 rustc_attr_parsing = { path = "../rustc_attr_parsing" }
 rustc_data_structures = { path = "../rustc_data_structures" }

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,
@@ -43,17 +43,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     stmts.push(hir::Stmt { hir_id, kind, span });
                 }
                 StmtKind::Item(it) => {
-                    stmts.extend(self.lower_item_ref(it).into_iter().enumerate().map(
-                        |(i, item_id)| {
-                            let hir_id = match i {
-                                0 => self.lower_node_id(s.id),
-                                _ => self.next_id(),
-                            };
-                            let kind = hir::StmtKind::Item(item_id);
-                            let span = self.lower_span(s.span);
-                            hir::Stmt { hir_id, kind, span }
-                        },
-                    ));
+                    let item_id = self.lower_item_ref(it);
+                    let hir_id = self.lower_node_id(s.id);
+                    let kind = hir::StmtKind::Item(item_id);
+                    let span = self.lower_span(s.span);
+                    stmts.push(hir::Stmt { hir_id, kind, span });
                 }
                 StmtKind::Expr(e) => {
                     let e = self.lower_expr(e);

compiler/rustc_ast_lowering/src/delegation.rs

@@ -46,12 +46,15 @@ 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::symbol::kw;
 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,
@@ -60,22 +63,7 @@ pub(crate) struct DelegationResults<'hir> {
     pub generics: &'hir hir::Generics<'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,
-        item_id: NodeId,
-        path_id: NodeId,
-        span: Span,
-        is_in_trait_impl: bool,
-    ) -> bool {
-        let sig_id = self.get_delegation_sig_id(item_id, path_id, span, is_in_trait_impl);
-        let Ok(sig_id) = sig_id else {
-            return false;
-        };
-        self.is_method(sig_id, span)
-    }
-
+impl<'hir> LoweringContext<'hir> {
     fn is_method(&self, def_id: DefId, span: Span) -> bool {
         match self.tcx.def_kind(def_id) {
             DefKind::Fn => false,
@@ -101,10 +89,11 @@ impl<'hir> LoweringContext<'_, 'hir> {
         let sig_id = self.get_delegation_sig_id(item_id, delegation.id, span, is_in_trait_impl);
         match sig_id {
             Ok(sig_id) => {
+                let is_method = self.is_method(sig_id, span);
                 let (param_count, c_variadic) = self.param_count(sig_id);
                 let decl = self.lower_delegation_decl(sig_id, param_count, c_variadic, span);
                 let sig = self.lower_delegation_sig(sig_id, decl, span);
-                let body_id = self.lower_delegation_body(delegation, param_count, span);
+                let body_id = self.lower_delegation_body(delegation, is_method, param_count, span);
                 let ident = self.lower_ident(delegation.ident);
                 let generics = self.lower_delegation_generics(span);
                 DelegationResults { body_id, sig, ident, generics }
@@ -125,8 +114,7 @@ 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,
@@ -234,10 +222,21 @@ impl<'hir> LoweringContext<'_, 'hir> {
         hir::FnSig { decl, header, span }
     }
 
-    fn generate_param(&mut self, idx: usize, span: Span) -> (hir::Param<'hir>, NodeId) {
+    fn generate_param(
+        &mut self,
+        is_method: bool,
+        idx: usize,
+        span: Span,
+    ) -> (hir::Param<'hir>, NodeId) {
         let pat_node_id = self.next_node_id();
         let pat_id = self.lower_node_id(pat_node_id);
-        let ident = Ident::with_dummy_span(Symbol::intern(&format!("arg{idx}")));
+        // FIXME(cjgillot) AssocItem currently relies on self parameter being exactly named `self`.
+        let name = if is_method && idx == 0 {
+            kw::SelfLower
+        } else {
+            Symbol::intern(&format!("arg{idx}"))
+        };
+        let ident = Ident::with_dummy_span(name);
         let pat = self.arena.alloc(hir::Pat {
             hir_id: pat_id,
             kind: hir::PatKind::Binding(hir::BindingMode::NONE, pat_id, ident, None),
@@ -248,9 +247,21 @@ impl<'hir> LoweringContext<'_, 'hir> {
         (hir::Param { hir_id: self.next_id(), pat, ty_span: span, span }, pat_node_id)
     }
 
-    fn generate_arg(&mut self, idx: usize, param_id: HirId, span: Span) -> hir::Expr<'hir> {
+    fn generate_arg(
+        &mut self,
+        is_method: bool,
+        idx: usize,
+        param_id: HirId,
+        span: Span,
+    ) -> hir::Expr<'hir> {
+        // FIXME(cjgillot) AssocItem currently relies on self parameter being exactly named `self`.
+        let name = if is_method && idx == 0 {
+            kw::SelfLower
+        } else {
+            Symbol::intern(&format!("arg{idx}"))
+        };
         let segments = self.arena.alloc_from_iter(iter::once(hir::PathSegment {
-            ident: Ident::with_dummy_span(Symbol::intern(&format!("arg{idx}"))),
+            ident: Ident::with_dummy_span(name),
             hir_id: self.next_id(),
             res: Res::Local(param_id),
             args: None,
@@ -264,6 +275,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
     fn lower_delegation_body(
         &mut self,
         delegation: &Delegation,
+        is_method: bool,
         param_count: usize,
         span: Span,
     ) -> BodyId {
@@ -274,14 +286,14 @@ impl<'hir> LoweringContext<'_, 'hir> {
             let mut args: Vec<hir::Expr<'_>> = Vec::with_capacity(param_count);
 
             for idx in 0..param_count {
-                let (param, pat_node_id) = this.generate_param(idx, span);
+                let (param, pat_node_id) = this.generate_param(is_method, idx, span);
                 parameters.push(param);
 
                 let arg = if let Some(block) = block
                     && idx == 0
                 {
                     let mut self_resolver = SelfResolver {
-                        resolver: this.resolver,
+                        ctxt: this,
                         path_id: delegation.id,
                         self_param_id: pat_node_id,
                     };
@@ -290,7 +302,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     this.ident_and_label_to_local_id.insert(pat_node_id, param.pat.hir_id.local_id);
                     this.lower_target_expr(&block)
                 } else {
-                    this.generate_arg(idx, param.pat.hir_id, span)
+                    this.generate_arg(is_method, idx, param.pat.hir_id, span)
                 };
                 args.push(arg);
             }
@@ -427,25 +439,25 @@ 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

@@ -3,12 +3,12 @@ use std::sync::Arc;
 
 use rustc_ast::ptr::P as AstP;
 use rustc_ast::*;
-use rustc_ast_pretty::pprust::expr_to_string;
 use rustc_attr_data_structures::{AttributeKind, find_attr};
 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;
@@ -52,7 +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)))
     }
@@ -462,13 +462,16 @@ impl<'hir> LoweringContext<'_, 'hir> {
         let mut invalid_expr_error = |tcx: TyCtxt<'_>, span| {
             // Avoid emitting the error multiple times.
             if error.is_none() {
+                let sm = tcx.sess.source_map();
                 let mut const_args = vec![];
                 let mut other_args = vec![];
                 for (idx, arg) in args.iter().enumerate() {
-                    if legacy_args_idx.contains(&idx) {
-                        const_args.push(format!("{{ {} }}", expr_to_string(arg)));
-                    } else {
-                        other_args.push(expr_to_string(arg));
+                    if let Ok(arg) = sm.span_to_snippet(arg.span) {
+                        if legacy_args_idx.contains(&idx) {
+                            const_args.push(format!("{{ {} }}", arg));
+                        } else {
+                            other_args.push(arg);
+                        }
                     }
                 }
                 let suggestion = UseConstGenericArg {
@@ -488,7 +491,13 @@ 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 {
@@ -1260,7 +1269,7 @@ 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(..)
@@ -1320,7 +1329,7 @@ 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()
                 {
@@ -1342,7 +1351,7 @@ 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()
                 {