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

Make lowering incremental, take 3/N

Author: rust-bors[bot]

Cargo.lock

@@ -3399,7 +3399,6 @@ version = "0.0.0"
 dependencies = [
  "rustc_abi",
  "rustc_ast",
- "rustc_ast_pretty",
  "rustc_attr_parsing",
  "rustc_data_structures",
  "rustc_errors",

compiler/rustc_ast/src/ast.rs

@@ -4027,6 +4027,17 @@ impl TryFrom<ItemKind> for ForeignItemKind {
 
 pub type ForeignItem = Item<ForeignItemKind>;
 
+#[derive(Debug)]
+pub enum AstOwner {
+    NonOwner,
+    Synthetic(rustc_span::def_id::LocalDefId),
+    Crate(Box<Crate>),
+    Item(Box<Item>),
+    TraitItem(Box<AssocItem>),
+    ImplItem(Box<AssocItem>),
+    ForeignItem(Box<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

@@ -362,7 +362,10 @@ 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_parsing = { path = "../rustc_attr_parsing" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_errors = { path = "../rustc_errors" }

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,
@@ -201,7 +201,6 @@ 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

@@ -6,7 +6,7 @@ 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,
@@ -44,17 +44,11 @@ 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/contract.rs

@@ -2,7 +2,7 @@ use thin_vec::thin_vec;
 
 use crate::LoweringContext;
 
-impl<'a, 'hir> LoweringContext<'a, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     /// Lowered contracts are guarded with the `contract_checks` compiler flag,
     /// i.e. the flag turns into a boolean guard in the lowered HIR. The reason
     /// for not eliminating the contract code entirely when the `contract_checks`

compiler/rustc_ast_lowering/src/delegation.rs

@@ -46,13 +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,
@@ -61,7 +63,7 @@ pub(crate) struct DelegationResults<'hir> {
     pub generics: &'hir hir::Generics<'hir>,
 }
 
-impl<'hir> LoweringContext<'_, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     fn is_method(&self, def_id: DefId, span: Span) -> bool {
         match self.tcx.def_kind(def_id) {
             DefKind::Fn => false,
@@ -112,8 +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,
@@ -292,7 +293,7 @@ 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,
                     };
@@ -438,25 +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

@@ -2,7 +2,6 @@ use std::ops::ControlFlow;
 use std::sync::Arc;
 
 use rustc_ast::*;
-use rustc_ast_pretty::pprust::expr_to_string;
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_hir as hir;
 use rustc_hir::attrs::AttributeKind;
@@ -52,7 +51,7 @@ impl<'v> rustc_ast::visit::Visitor<'v> for WillCreateDefIdsVisitor {
     }
 }
 
-impl<'hir> LoweringContext<'_, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     fn lower_exprs(&mut self, exprs: &[Box<Expr>]) -> &'hir [hir::Expr<'hir>] {
         self.arena.alloc_from_iter(exprs.iter().map(|x| self.lower_expr_mut(x)))
     }
@@ -436,13 +435,16 @@ 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 {
@@ -1205,7 +1207,7 @@ 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(..)
@@ -1265,7 +1267,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
     ) -> Option<(&'a Option<Box<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()
                 {
@@ -1287,7 +1289,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
     ) -> Option<(&'a Option<Box<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::{DesugaringKind, 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.
@@ -236,7 +236,7 @@ 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,
@@ -285,7 +285,7 @@ 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>>,
@@ -336,7 +336,7 @@ 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>>,
@@ -397,7 +397,7 @@ 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,