Use find_or_find_insert_slot for query execution

compiler/rustc_query_system/src/query/plumbing.rs

@@ -328,21 +328,38 @@ where
 
     let current_job_id = qcx.current_query_job();
 
-    match state_lock.raw_entry_mut().from_key_hashed_nocheck(key_hash, &key) {
-        RawEntryMut::Vacant(entry) => {
+    match state_lock.raw_table_mut().find_or_find_insert_slot(
+        key_hash,
+        |(k, _)| *k == key,
+        |(k, _)| sharded::make_hash(k),
+    ) {
+        Err(free_slot) => {
             // Nothing has computed or is computing the query, so we start a new job and insert it in the
             // state map.
             let id = qcx.next_job_id();
             let job = QueryJob::new(id, span, current_job_id);
-            entry.insert_hashed_nocheck(key_hash, key, QueryResult::Started(job));
+
+            // SAFETY: The slot is still valid as there's
+            // been no mutation to the table since we hold the lock.
+            unsafe {
+                state_lock.raw_table_mut().insert_in_slot(
+                    key_hash,
+                    free_slot,
+                    (key, QueryResult::Started(job)),
+                );
+            }
 
             // Drop the lock before we start executing the query
             drop(state_lock);
 
             execute_job::<_, _, INCR>(query, qcx, state, key, key_hash, id, dep_node)
         }
-        RawEntryMut::Occupied(mut entry) => {
-            match entry.get_mut() {
+        Ok(bucket) => {
+            // SAFETY: We know this bucket is still valid
+            // since we just got it from `find_or_find_insert_slot`.
+            let entry = unsafe { &mut bucket.as_mut().1 };
+
+            match entry {
                 QueryResult::Started(job) => {
                     #[cfg(parallel_compiler)]
                     if sync::is_dyn_thread_safe() {