From d39fefdd694b02c7e7b4a64ccbb38d9f8be16df0 Mon Sep 17 00:00:00 2001
From: SparrowLii <liyuan179@huawei.com>
Date: Mon, 1 Aug 2022 10:23:09 +0800
Subject: [PATCH] use type alias impl trait in `outlives_bounds::InferCtxtExt`

---
 .../rustc_mir_dataflow/src/framework/mod.rs   |  3 ++-
 compiler/rustc_typeck/src/check/wfcheck.rs    |  2 +-
 .../src/impl_wf_check/min_specialization.rs   | 10 ++++++++
 compiler/rustc_typeck/src/lib.rs              |  1 +
 .../src/outlives/outlives_bounds.rs           | 24 +++++++++----------
 5 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/compiler/rustc_mir_dataflow/src/framework/mod.rs b/compiler/rustc_mir_dataflow/src/framework/mod.rs
index f9fd6c9c56b..d9aff94fef2 100644
--- a/compiler/rustc_mir_dataflow/src/framework/mod.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/mod.rs
@@ -256,6 +256,7 @@ fn apply_switch_int_edge_effects(
     ///     .iterate_to_fixpoint()
     ///     .into_results_cursor(body);
     /// ```
+    #[inline]
     fn into_engine<'mir>(
         self,
         tcx: TyCtxt<'tcx>,
@@ -413,7 +414,7 @@ fn apply_switch_int_edge_effects(
     }
 
     /* Extension methods */
-
+    #[inline]
     fn into_engine<'mir>(
         self,
         tcx: TyCtxt<'tcx>,
diff --git a/compiler/rustc_typeck/src/check/wfcheck.rs b/compiler/rustc_typeck/src/check/wfcheck.rs
index 8396cb1ae0a..057e5f93563 100644
--- a/compiler/rustc_typeck/src/check/wfcheck.rs
+++ b/compiler/rustc_typeck/src/check/wfcheck.rs
@@ -699,7 +699,7 @@ fn resolve_regions_with_wf_tys<'tcx>(
         let outlives_environment = OutlivesEnvironment::with_bounds(
             param_env,
             Some(&infcx),
-            infcx.implied_bounds_tys(param_env, id, wf_tys.iter().map(|ty| *ty)),
+            infcx.implied_bounds_tys(param_env, id, wf_tys.clone()),
         );
         let region_bound_pairs = outlives_environment.region_bound_pairs();
 
diff --git a/compiler/rustc_typeck/src/impl_wf_check/min_specialization.rs b/compiler/rustc_typeck/src/impl_wf_check/min_specialization.rs
index 72af5d79e09..64cd69750f3 100644
--- a/compiler/rustc_typeck/src/impl_wf_check/min_specialization.rs
+++ b/compiler/rustc_typeck/src/impl_wf_check/min_specialization.rs
@@ -158,6 +158,16 @@ fn get_impl_substs<'tcx>(
 
 
 
+
+
+
+
+
+
+
+
+
+
         let errors = ocx.select_all_or_error();
         if !errors.is_empty() {
             ocx.infcx.report_fulfillment_errors(&errors, None, false);
diff --git a/compiler/rustc_typeck/src/lib.rs b/compiler/rustc_typeck/src/lib.rs
index 8c6fb6a7718..1ff9c627131 100644
--- a/compiler/rustc_typeck/src/lib.rs
+++ b/compiler/rustc_typeck/src/lib.rs
@@ -72,6 +72,7 @@
 #![feature(slice_partition_dedup)]
 #![feature(try_blocks)]
 #![feature(is_some_with)]
+#![feature(type_alias_impl_trait)]
 #![recursion_limit = "256"]
 
 #[macro_use]
diff --git a/compiler/rustc_typeck/src/outlives/outlives_bounds.rs b/compiler/rustc_typeck/src/outlives/outlives_bounds.rs
index 769a3e7e11a..024e20d9223 100644
--- a/compiler/rustc_typeck/src/outlives/outlives_bounds.rs
+++ b/compiler/rustc_typeck/src/outlives/outlives_bounds.rs
@@ -1,3 +1,4 @@
+use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
 use rustc_hir::HirId;
 use rustc_middle::ty::{self, ParamEnv, Ty};
@@ -8,6 +9,7 @@
 
 pub use rustc_middle::traits::query::OutlivesBound;
 
+type Bounds<'a, 'tcx: 'a> = impl Iterator<Item = OutlivesBound<'tcx>> + 'a;
 pub trait InferCtxtExt<'a, 'tcx> {
     fn implied_outlives_bounds(
         &self,
@@ -20,8 +22,8 @@ fn implied_bounds_tys(
         &'a self,
         param_env: ty::ParamEnv<'tcx>,
         body_id: hir::HirId,
-        tys: impl IntoIterator<Item = Ty<'tcx>> + 'a,
-    ) -> Box<dyn Iterator<Item = OutlivesBound<'tcx>> + 'a>;
+        tys: FxHashSet<Ty<'tcx>>,
+    ) -> Bounds<'a, 'tcx>;
 }
 
 impl<'a, 'cx, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'cx, 'tcx> {
@@ -100,15 +102,13 @@ fn implied_bounds_tys(
         &'a self,
         param_env: ParamEnv<'tcx>,
         body_id: HirId,
-        tys: impl IntoIterator<Item = Ty<'tcx>> + 'a,
-    ) -> Box<dyn Iterator<Item = OutlivesBound<'tcx>> + 'a> {
-        Box::new(
-            tys.into_iter()
-                .map(move |ty| {
-                    let ty = self.resolve_vars_if_possible(ty);
-                    self.implied_outlives_bounds(param_env, body_id, ty)
-                })
-                .flatten(),
-        )
+        tys: FxHashSet<Ty<'tcx>>,
+    ) -> Bounds<'a, 'tcx> {
+        tys.into_iter()
+            .map(move |ty| {
+                let ty = self.resolve_vars_if_possible(ty);
+                self.implied_outlives_bounds(param_env, body_id, ty)
+            })
+            .flatten()
     }
 }