Benches: fix pushpop bench, fix insert bench, add remove bench

Author: arthurprs

benches/bench.rs

@@ -26,14 +26,33 @@ fn bench_push(b: &mut Bencher) {
 #[bench]
 fn bench_insert(b: &mut Bencher) {
     #[inline(never)]
-    fn insert_noinline(vec: &mut SmallVec<[u64; 16]>, x: u64) {
-        vec.insert(0, x)
+    fn insert_noinline(vec: &mut SmallVec<[u64; 16]>, p: usize, x: u64) {
+        vec.insert(p, x)
     }
 
     b.iter(|| {
         let mut vec: SmallVec<[u64; 16]> = SmallVec::new();
+        // insert at the end - 1 so we don't benchmark ptr::copy instead
+        vec.insert(0, 0);
         for x in 0..100 {
-            insert_noinline(&mut vec, x);
+            insert_noinline(&mut vec, x, x as u64);
+        }
+        vec
+    });
+}
+
+#[bench]
+fn bench_remove(b: &mut Bencher) {
+    #[inline(never)]
+    fn remove_noinline(vec: &mut SmallVec<[u64; 16]>, p: usize) -> u64 {
+        vec.remove(p)
+    }
+
+    b.iter(|| {
+        let mut vec: SmallVec<[u64; 16]> = smallvec![0; 101];
+        // remove 1 element from the end so we don't benchmark ptr::copy instead
+        for x in (0..100).rev() {
+            remove_noinline(&mut vec, x);
         }
         vec
     });
@@ -97,11 +116,10 @@ fn bench_insert_from_slice(b: &mut Bencher) {
 #[bench]
 fn bench_pushpop(b: &mut Bencher) {
     #[inline(never)]
-    fn pushpop_noinline(vec: &mut SmallVec<[u64; 16]>, x: u64) {
+    fn pushpop_noinline(vec: &mut SmallVec<[u64; 16]>, x: u64) -> Option<u64> {
         vec.push(x);
-        vec.pop();
+        vec.pop()
     }
-
     b.iter(|| {
         let mut vec: SmallVec<[u64; 16]> = SmallVec::new();
         for x in 0..100 {