From a12f50ddc4ed73cbca436827ae3958a104d915d3 Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Mon, 8 May 2023 15:12:45 -0700
Subject: rustc_metadata: use configurable AtomicBool for privateness flag

This switches to using a `Cell` for single-threaded rustc.
---
 compiler/rustc_data_structures/src/sync.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

(limited to 'compiler/rustc_data_structures')

diff --git a/compiler/rustc_data_structures/src/sync.rs b/compiler/rustc_data_structures/src/sync.rs
index 6c3197d8ec2..df8285cc729 100644
--- a/compiler/rustc_data_structures/src/sync.rs
+++ b/compiler/rustc_data_structures/src/sync.rs
@@ -143,6 +143,20 @@ cfg_if! {
                 self.0.set(val);
                 result
             }
+            pub fn fetch_update(
+                &self,
+                _order_set: Ordering,
+                _order_get: Ordering,
+                mut f: impl FnMut(bool) -> Option<bool>,
+            ) -> Result<bool, bool> {
+                let prev = self.0.get();
+                if let Some(next) = f(prev) {
+                    self.0.set(next);
+                    Ok(prev)
+                } else {
+                    Err(prev)
+                }
+            }
         }
 
         impl<T: Copy + PartialEq> Atomic<T> {
-- 
cgit 1.4.1-3-g733a5


From 6a358960da438efca794020bf5497b41ce3ffe17 Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Tue, 9 May 2023 13:46:54 -0700
Subject: rustc_metadata: specialize private_dep flag with `fetch_and`

---
 compiler/rustc_data_structures/src/sync.rs   | 17 ++++-------------
 compiler/rustc_metadata/src/creader.rs       |  2 +-
 compiler/rustc_metadata/src/rmeta/decoder.rs |  7 ++-----
 3 files changed, 7 insertions(+), 19 deletions(-)

(limited to 'compiler/rustc_data_structures')

diff --git a/compiler/rustc_data_structures/src/sync.rs b/compiler/rustc_data_structures/src/sync.rs
index df8285cc729..96dc187611d 100644
--- a/compiler/rustc_data_structures/src/sync.rs
+++ b/compiler/rustc_data_structures/src/sync.rs
@@ -143,19 +143,10 @@ cfg_if! {
                 self.0.set(val);
                 result
             }
-            pub fn fetch_update(
-                &self,
-                _order_set: Ordering,
-                _order_get: Ordering,
-                mut f: impl FnMut(bool) -> Option<bool>,
-            ) -> Result<bool, bool> {
-                let prev = self.0.get();
-                if let Some(next) = f(prev) {
-                    self.0.set(next);
-                    Ok(prev)
-                } else {
-                    Err(prev)
-                }
+            pub fn fetch_and(&self, val: bool, _: Ordering) -> bool {
+                let result = self.0.get() & val;
+                self.0.set(val);
+                result
             }
         }
 
diff --git a/compiler/rustc_metadata/src/creader.rs b/compiler/rustc_metadata/src/creader.rs
index 63a2dc5aa62..4c872664c3d 100644
--- a/compiler/rustc_metadata/src/creader.rs
+++ b/compiler/rustc_metadata/src/creader.rs
@@ -570,7 +570,7 @@ impl<'a, 'tcx> CrateLoader<'a, 'tcx> {
                 }
                 data.update_dep_kind(|data_dep_kind| cmp::max(data_dep_kind, dep_kind));
                 if let Some(private_dep) = private_dep {
-                    data.update_private_dep(|p_d| p_d && private_dep);
+                    data.update_and_private_dep(private_dep);
                 }
                 Ok(cnum)
             }
diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs
index 325ffcae7e9..d2995b198f6 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder.rs
@@ -1668,11 +1668,8 @@ impl CrateMetadata {
         self.dep_kind.with_lock(|dep_kind| *dep_kind = f(*dep_kind))
     }
 
-    /// `f` must not perform any I/O or take any locks. It may be called more than once.
-    pub(crate) fn update_private_dep(&self, mut f: impl FnMut(bool) -> bool) {
-        self.private_dep
-            .fetch_update(Ordering::Release, Ordering::Acquire, |private_dep| Some(f(private_dep)))
-            .expect("fetch_update only returns Err if `f` returns None`, which it doesn't");
+    pub(crate) fn update_and_private_dep(&self, private_dep: bool) {
+        self.private_dep.fetch_and(private_dep, Ordering::SeqCst);
     }
 
     pub(crate) fn required_panic_strategy(&self) -> Option<PanicStrategy> {
-- 
cgit 1.4.1-3-g733a5


From 52bd82f522c4f3d9bd0dc534c06169285afbc23b Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Thu, 25 May 2023 15:18:05 -0700
Subject: rustc_data_structures: sync and atomic consistency

Co-authored-by: @lukas-code
---
 compiler/rustc_data_structures/src/sync.rs | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

(limited to 'compiler/rustc_data_structures')

diff --git a/compiler/rustc_data_structures/src/sync.rs b/compiler/rustc_data_structures/src/sync.rs
index 96dc187611d..25a08237346 100644
--- a/compiler/rustc_data_structures/src/sync.rs
+++ b/compiler/rustc_data_structures/src/sync.rs
@@ -139,14 +139,14 @@ cfg_if! {
 
         impl Atomic<bool> {
             pub fn fetch_or(&self, val: bool, _: Ordering) -> bool {
-                let result = self.0.get() | val;
-                self.0.set(val);
-                result
+                let old = self.0.get();
+                self.0.set(val | old);
+                old
             }
             pub fn fetch_and(&self, val: bool, _: Ordering) -> bool {
-                let result = self.0.get() & val;
-                self.0.set(val);
-                result
+                let old = self.0.get();
+                self.0.set(val & old);
+                old
             }
         }
 
-- 
cgit 1.4.1-3-g733a5