arrayslice_test.go

package arrayslice

import "testing"

func BenchmarkArray8for(b *testing.B) {
	var a [8]int
	for i := 0; i < b.N; i++ {
		for j := 0; j < len(a); j++ {
			a[j] += j
		}
	}
}

func BenchmarkArray8range(b *testing.B) {
	var a [8]int
	for i := 0; i < b.N; i++ {
		for i := range a {
			a[i] += i
		}
	}
}

func BenchmarkSlice8for(b *testing.B) {
	var s = []int{0, 0, 0, 0, 0, 0, 0, 0}
	for i := 0; i < b.N; i++ {
		for j, n := 0, len(s); j < n; j++ {
			s[j] += j
		}
	}
}

func BenchmarkSlice8range(b *testing.B) {
	var s = []int{0, 0, 0, 0, 0, 0, 0, 0}
	for i := 0; i < b.N; i++ {
		for i := range s {
			s[i] += i
		}
	}
}

func BenchmarkSlice8unroll(b *testing.B) {
	var s = []int{0, 0, 0, 0, 0, 0, 0, 0}
	for i := 0; i < b.N; i++ {
		s[0] += 0
		s[1] += 1
		s[2] += 2
		s[3] += 3
		s[4] += 4
		s[5] += 5
		s[6] += 6
		s[7] += 7
	}
}

func BenchmarkArray8unroll(b *testing.B) {
	var a [8]int
	for i := 0; i < b.N; i++ {
		a[0] += 0
		a[1] += 1
		a[2] += 2
		a[3] += 3
		a[4] += 4
		a[5] += 5
		a[6] += 6
		a[7] += 7
	}
}

func BenchmarkStruct8(b *testing.B) {
	var t = struct{ i0, i1, i2, i3, i4, i5, i6, i7 int }{}
	for i := 0; i < b.N; i++ {
		t.i0 += 0
		t.i1 += 1
		t.i2 += 2
		t.i3 += 3
		t.i4 += 4
		t.i5 += 5
		t.i6 += 6
		t.i7 += 7
	}
}

gistfile1.txt

 wes-macbook:arrayslice go test -bench=.
testing: warning: no tests to run
PASS
BenchmarkArray8for	200000000	         8.96 ns/op
BenchmarkArray8range	100000000	        10.0 ns/op
BenchmarkSlice8for	100000000	        10.1 ns/op
BenchmarkSlice8range	100000000	        10.4 ns/op
BenchmarkSlice8unroll	500000000	         6.02 ns/op
BenchmarkArray8unroll	500000000	         2.63 ns/op
BenchmarkStruct8	1000000000	         2.81 ns/op
ok  	_/Users/wfreeman/arrayslice	14.074s