Add a usize-indexed append-only-vec

compiler/rustc_data_structures/src/sync.rs

@@ -51,7 +51,7 @@ use std::panic::{catch_unwind, resume_unwind, AssertUnwindSafe};
 pub use std::sync::atomic::Ordering;
 pub use std::sync::atomic::Ordering::SeqCst;
 
-pub use vec::AppendOnlyVec;
+pub use vec::{AppendOnlyIndexVec, AppendOnlyVec};
 
 mod vec;
 

compiler/rustc_data_structures/src/sync/vec.rs

@@ -2,7 +2,7 @@ use std::marker::PhantomData;
 
 use rustc_index::vec::Idx;
 
-pub struct AppendOnlyVec<I: Idx, T: Copy> {
+pub struct AppendOnlyIndexVec<I: Idx, T: Copy> {
     #[cfg(not(parallel_compiler))]
     vec: elsa::vec::FrozenVec<T>,
     #[cfg(parallel_compiler)]
@@ -10,7 +10,7 @@ pub struct AppendOnlyVec<I: Idx, T: Copy> {
     _marker: PhantomData<fn(&I)>,
 }
 
-impl<I: Idx, T: Copy> AppendOnlyVec<I, T> {
+impl<I: Idx, T: Copy> AppendOnlyIndexVec<I, T> {
     pub fn new() -> Self {
         Self {
             #[cfg(not(parallel_compiler))]
@@ -39,3 +39,35 @@ impl<I: Idx, T: Copy> AppendOnlyVec<I, T> {
         return self.vec.get(i);
     }
 }
+
+pub struct AppendOnlyVec<T: Copy> {
+    #[cfg(not(parallel_compiler))]
+    vec: elsa::vec::FrozenVec<T>,
+    #[cfg(parallel_compiler)]
+    vec: elsa::sync::LockFreeFrozenVec<T>,
+}
+
+impl<T: Copy> AppendOnlyVec<T> {
+    pub fn new() -> Self {
+        Self {
+            #[cfg(not(parallel_compiler))]
+            vec: elsa::vec::FrozenVec::new(),
+            #[cfg(parallel_compiler)]
+            vec: elsa::sync::LockFreeFrozenVec::new(),
+        }
+    }
+
+    pub fn push(&self, val: T) {
+        #[cfg(not(parallel_compiler))]
+        self.vec.push(val);
+        #[cfg(parallel_compiler)]
+        self.vec.push(val)
+    }
+
+    pub fn get(&self, i: usize) -> Option<T> {
+        #[cfg(not(parallel_compiler))]
+        return self.vec.get_copy(i);
+        #[cfg(parallel_compiler)]
+        return self.vec.get(i);
+    }
+}