Add benchmarks for start_with and ends_with

src/libcore/benches/lib.rs

@@ -11,4 +11,5 @@ mod hash;
 mod iter;
 mod num;
 mod ops;
+mod pattern;
 mod slice;

src/libcore/benches/pattern.rs

@@ -0,0 +1,43 @@
+use test::black_box;
+use test::Bencher;
+
+#[bench]
+fn starts_with_char(b: &mut Bencher) {
+    let text = black_box("kdjsfhlakfhlsghlkvcnljknfqiunvcijqenwodind");
+    b.iter(|| {
+        for _ in 0..1024 {
+            black_box(text.starts_with('k'));
+        }
+    })
+}
+
+#[bench]
+fn starts_with_str(b: &mut Bencher) {
+    let text = black_box("kdjsfhlakfhlsghlkvcnljknfqiunvcijqenwodind");
+    b.iter(|| {
+        for _ in 0..1024 {
+            black_box(text.starts_with("k"));
+        }
+    })
+}
+
+
+#[bench]
+fn ends_with_char(b: &mut Bencher) {
+    let text = black_box("kdjsfhlakfhlsghlkvcnljknfqiunvcijqenwodind");
+    b.iter(|| {
+        for _ in 0..1024 {
+            black_box(text.ends_with('k'));
+        }
+    })
+}
+
+#[bench]
+fn ends_with_str(b: &mut Bencher) {
+    let text = black_box("kdjsfhlakfhlsghlkvcnljknfqiunvcijqenwodind");
+    b.iter(|| {
+        for _ in 0..1024 {
+            black_box(text.ends_with("k"));
+        }
+    })
+}