Add benchmarks: generate 1k block

benches/misc.rs

@@ -5,7 +5,7 @@ extern crate rand;
 
 use test::{black_box, Bencher};
 
-use rand::{Rng, weak_rng};
+use rand::{Rng, RngCore, weak_rng};
 use rand::seq::*;
 
 #[bench]
@@ -60,3 +60,56 @@ macro_rules! sample_indices {
 sample_indices!(misc_sample_indices_10_of_1k, 10, 1000);
 sample_indices!(misc_sample_indices_50_of_1k, 50, 1000);
 sample_indices!(misc_sample_indices_100_of_1k, 100, 1000);
+
+#[bench]
+fn gen_1k_iter_repeat(b: &mut Bencher) {
+    use std::iter;
+    let mut rng = weak_rng();
+    b.iter(|| {
+        let v: Vec<u32> = iter::repeat(()).map(|()| rng.next_u32()).take(256).collect();
+        black_box(v);
+    });
+    b.bytes = 1024;
+}
+
+#[bench]
+fn gen_1k_gen_iter(b: &mut Bencher) {
+    let mut rng = weak_rng();
+    b.iter(|| {
+        let v: Vec<u32> = rng.gen_iter().take(256).collect();
+        black_box(v);
+    });
+    b.bytes = 1024;
+}
+
+#[bench]
+fn gen_1k_iter1(b: &mut Bencher) {
+    let mut rng = weak_rng();
+    b.iter(|| {
+        let v: Vec<u32> = rng.iter().take(256).map(|rng| rng.next_u32()).collect();
+        black_box(v);
+    });
+    b.bytes = 1024;
+}
+
+#[bench]
+fn gen_1k_iter2(b: &mut Bencher) {
+    let mut rng = weak_rng();
+    b.iter(|| {
+        let v: Vec<u32> = rng.iter().map(|rng| rng.next_u32()).take(256).collect();
+        black_box(v);
+    });
+    b.bytes = 1024;
+}
+
+#[bench]
+fn gen_1k_fill(b: &mut Bencher) {
+    use std::mem::transmute;
+    let mut rng = weak_rng();
+    let mut buf = [0u32; 256];
+    b.iter(|| {
+        rng.fill_bytes(unsafe{ transmute(&mut buf[..]) });
+        black_box(buf);
+    });
+    b.bytes = 1024;
+}