Make AST->HIR lowering incremental

Cargo.lock

@@ -3474,6 +3474,7 @@ dependencies = [
  "rustc_errors",
  "rustc_hir",
  "rustc_index",
+ "rustc_middle",
  "rustc_query_system",
  "rustc_session",
  "rustc_span",
@@ -3808,6 +3809,7 @@ name = "rustc_hir"
 version = "0.0.0"
 dependencies = [
  "odht",
+ "rustc_arena",
  "rustc_ast",
  "rustc_data_structures",
  "rustc_error_messages",
@@ -3901,6 +3903,7 @@ dependencies = [
  "rustc_expand",
  "rustc_hir",
  "rustc_incremental",
+ "rustc_index",
  "rustc_lint",
  "rustc_metadata",
  "rustc_middle",
@@ -4276,7 +4279,6 @@ dependencies = [
  "bitflags",
  "rustc_arena",
  "rustc_ast",
- "rustc_ast_lowering",
  "rustc_ast_pretty",
  "rustc_attr",
  "rustc_data_structures",

compiler/rustc_ast_lowering/Cargo.toml

@@ -14,6 +14,7 @@ rustc_hir = { path = "../rustc_hir" }
 rustc_target = { path = "../rustc_target" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_index = { path = "../rustc_index" }
+rustc_middle = { path = "../rustc_middle" }
 rustc_query_system = { path = "../rustc_query_system" }
 rustc_span = { path = "../rustc_span" }
 rustc_errors = { path = "../rustc_errors" }

compiler/rustc_ast_lowering/src/asm.rs

@@ -1,4 +1,4 @@
-use crate::{ImplTraitContext, ImplTraitPosition, ParamMode};
+use crate::{ImplTraitContext, ImplTraitPosition, ParamMode, ResolverAstLoweringExt};
 
 use super::LoweringContext;
 
@@ -16,7 +16,7 @@ use rustc_target::asm;
 use std::collections::hash_map::Entry;
 use std::fmt::Write;
 
-impl<'a, 'hir> LoweringContext<'a, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     crate fn lower_inline_asm(&mut self, sp: Span, asm: &InlineAsm) -> &'hir hir::InlineAsm<'hir> {
         // Rustdoc needs to support asm! from foreign architectures: don't try
         // lowering the register constraints in this case.
@@ -238,8 +238,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
 
                             // Wrap the expression in an AnonConst.
                             let parent_def_id = self.current_hir_id_owner;
-                            let node_id = self.resolver.next_node_id();
-                            self.resolver.create_def(
+                            let node_id = self.next_node_id();
+                            self.create_def(
                                 parent_def_id,
                                 node_id,
                                 DefPathData::AnonConst,

compiler/rustc_ast_lowering/src/block.rs

@@ -6,7 +6,7 @@ use rustc_span::{sym, DesugaringKind};
 
 use smallvec::SmallVec;
 
-impl<'a, 'hir> LoweringContext<'a, 'hir> {
+impl<'hir> LoweringContext<'hir> {
     pub(super) fn lower_block(
         &mut self,
         b: &Block,

compiler/rustc_ast_lowering/src/expr.rs

@@ -1,6 +1,6 @@
-use crate::{FnDeclKind, ImplTraitPosition};
-
+use super::ResolverAstLoweringExt;
 use super::{ImplTraitContext, LoweringContext, ParamMode, ParenthesizedGenericArgs};
+use crate::{FnDeclKind, ImplTraitPosition};
 
 use rustc_ast::attr;
 use rustc_ast::ptr::P as AstP;
@@ -16,7 +16,7 @@ use rustc_span::source_map::{respan, DesugaringKind, Span, Spanned};
 use rustc_span::symbol::{sym, Ident};
 use rustc_span::DUMMY_SP;
 
-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)))
     }
@@ -339,10 +339,10 @@ impl<'hir> LoweringContext<'_, 'hir> {
         for (idx, arg) in args.into_iter().enumerate() {
             if legacy_args_idx.contains(&idx) {
                 let parent_def_id = self.current_hir_id_owner;
-                let node_id = self.resolver.next_node_id();
+                let node_id = self.next_node_id();
 
                 // Add a definition for the in-band const def.
-                self.resolver.create_def(
+                self.create_def(
                     parent_def_id,
                     node_id,
                     DefPathData::AnonConst,
@@ -702,7 +702,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         };
 
         // `::std::task::Poll::Ready(result) => break result`
-        let loop_node_id = self.resolver.next_node_id();
+        let loop_node_id = self.next_node_id();
         let loop_hir_id = self.lower_node_id(loop_node_id);
         let ready_arm = {
             let x_ident = Ident::with_dummy_span(sym::result);
@@ -947,7 +947,7 @@ 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(..)

compiler/rustc_ast_lowering/src/index.rs

@@ -6,6 +6,7 @@ use rustc_hir::definitions;
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::*;
 use rustc_index::vec::{Idx, IndexVec};
+use rustc_middle::span_bug;
 use rustc_session::Session;
 use rustc_span::source_map::SourceMap;
 use rustc_span::{Span, DUMMY_SP};
@@ -75,7 +76,8 @@ impl<'a, 'hir> NodeCollector<'a, 'hir> {
         // owner of that node.
         if cfg!(debug_assertions) {
             if hir_id.owner != self.owner {
-                panic!(
+                span_bug!(
+                    span,
                     "inconsistent DepNode at `{:?}` for `{:?}`: \
                      current_dep_node_owner={} ({:?}), hir_id.owner={} ({:?})",
                     self.source_map.span_to_diagnostic_string(span),