Add benchmarks for .assign_scalar(&0.)

Should be memset but is not in current rust nightly.

Author: bluss

benches/bench1.rs

@@ -373,12 +373,12 @@ fn muladd_2d_f32_blas(bench: &mut test::Bencher)
 }
 
 #[bench]
-fn assign_scalar_2d_large(bench: &mut test::Bencher)
+fn assign_scalar_2d_corder(bench: &mut test::Bencher)
 {
     let a = OwnedArray::zeros((64, 64));
     let mut a = black_box(a);
     let s = 3.;
-    bench.iter(|| a.assign_scalar(&s))
+    bench.iter(move || a.assign_scalar(&s))
 }
 
 #[bench]
@@ -388,26 +388,43 @@ fn assign_scalar_2d_cutout(bench: &mut test::Bencher)
     let a = a.slice_mut(s![1..-1, 1..-1]);
     let mut a = black_box(a);
     let s = 3.;
-    bench.iter(|| a.assign_scalar(&s))
+    bench.iter(move || a.assign_scalar(&s))
 }
 
 #[bench]
-fn assign_scalar_2d_transposed_large(bench: &mut test::Bencher)
+fn assign_scalar_2d_forder(bench: &mut test::Bencher)
 {
     let mut a = OwnedArray::zeros((64, 64));
     a.swap_axes(0, 1);
     let mut a = black_box(a);
     let s = 3.;
-    bench.iter(|| a.assign_scalar(&s))
+    bench.iter(move || a.assign_scalar(&s))
 }
 
 #[bench]
-fn assign_scalar_2d_raw_large(bench: &mut test::Bencher)
+fn assign_zero_2d_corder(bench: &mut test::Bencher)
 {
     let a = OwnedArray::zeros((64, 64));
     let mut a = black_box(a);
-    let s = 3.;
-    bench.iter(|| for elt in a.raw_data_mut() { *elt = s; });
+    bench.iter(|| a.assign_scalar(&0.))
+}
+
+#[bench]
+fn assign_zero_2d_cutout(bench: &mut test::Bencher)
+{
+    let mut a = OwnedArray::zeros((66, 66));
+    let a = a.slice_mut(s![1..-1, 1..-1]);
+    let mut a = black_box(a);
+    bench.iter(|| a.assign_scalar(&0.))
+}
+
+#[bench]
+fn assign_zero_2d_forder(bench: &mut test::Bencher)
+{
+    let mut a = OwnedArray::zeros((64, 64));
+    a.swap_axes(0, 1);
+    let mut a = black_box(a);
+    bench.iter(|| a.assign_scalar(&0.))
 }
 
 #[bench]