Update SszEncoder

eth2/utils/ssz/benches/benches.rs

@@ -4,6 +4,15 @@ extern crate criterion;
 use criterion::black_box;
 use criterion::{Benchmark, Criterion};
 use ssz::{Decodable, Encodable};
+use ssz_derive::{Decode, Encode};
+
+#[derive(Clone, Copy, Encode, Decode)]
+pub struct FixedLen {
+    a: u64,
+    b: u64,
+    c: u64,
+    d: u64,
+}
 
 fn criterion_benchmark(c: &mut Criterion) {
     let n = 8196;
@@ -32,6 +41,39 @@ fn criterion_benchmark(c: &mut Criterion) {
         })
         .sample_size(100),
     );
+
+    let fixed_len = FixedLen {
+        a: 42,
+        b: 42,
+        c: 42,
+        d: 42,
+    };
+    let fixed_len_vec: Vec<FixedLen> = vec![fixed_len; 8196];
+
+    let vec = fixed_len_vec.clone();
+    c.bench(
+        &format!("vec_of_{}_struct", n),
+        Benchmark::new("as_ssz_bytes", move |b| {
+            b.iter_with_setup(|| vec.clone(), |vec| black_box(vec.as_ssz_bytes()))
+        })
+        .sample_size(100),
+    );
+
+    let vec = fixed_len_vec.clone();
+    let bytes = vec.as_ssz_bytes();
+    c.bench(
+        &format!("vec_of_{}_struct", n),
+        Benchmark::new("from_ssz_bytes", move |b| {
+            b.iter_with_setup(
+                || bytes.clone(),
+                |bytes| {
+                    let vec: Vec<u64> = Vec::from_ssz_bytes(&bytes).unwrap();
+                    black_box(vec)
+                },
+            )
+        })
+        .sample_size(100),
+    );
 }
 
 criterion_group!(benches, criterion_benchmark);