1// Copyright 2012 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package runtime_test
6
7import "testing"
8
9// arm soft division benchmarks adapted from
10// http://ridiculousfish.com/files/division_benchmarks.tar.gz
11
12const numeratorsSize = 1 << 21
13
14var numerators = randomNumerators()
15
16type randstate struct {
17	hi, lo uint32
18}
19
20func (r *randstate) rand() uint32 {
21	r.hi = r.hi<<16 + r.hi>>16
22	r.hi += r.lo
23	r.lo += r.hi
24	return r.hi
25}
26
27func randomNumerators() []uint32 {
28	numerators := make([]uint32, numeratorsSize)
29	random := &randstate{2147483563, 2147483563 ^ 0x49616E42}
30	for i := range numerators {
31		numerators[i] = random.rand()
32	}
33	return numerators
34}
35
36func bmUint32Div(divisor uint32, b *testing.B) {
37	var sum uint32
38	for i := 0; i < b.N; i++ {
39		sum += numerators[i&(numeratorsSize-1)] / divisor
40	}
41}
42
43func BenchmarkUint32Div7(b *testing.B)         { bmUint32Div(7, b) }
44func BenchmarkUint32Div37(b *testing.B)        { bmUint32Div(37, b) }
45func BenchmarkUint32Div123(b *testing.B)       { bmUint32Div(123, b) }
46func BenchmarkUint32Div763(b *testing.B)       { bmUint32Div(763, b) }
47func BenchmarkUint32Div1247(b *testing.B)      { bmUint32Div(1247, b) }
48func BenchmarkUint32Div9305(b *testing.B)      { bmUint32Div(9305, b) }
49func BenchmarkUint32Div13307(b *testing.B)     { bmUint32Div(13307, b) }
50func BenchmarkUint32Div52513(b *testing.B)     { bmUint32Div(52513, b) }
51func BenchmarkUint32Div60978747(b *testing.B)  { bmUint32Div(60978747, b) }
52func BenchmarkUint32Div106956295(b *testing.B) { bmUint32Div(106956295, b) }
53
54func bmUint32Mod(divisor uint32, b *testing.B) {
55	var sum uint32
56	for i := 0; i < b.N; i++ {
57		sum += numerators[i&(numeratorsSize-1)] % divisor
58	}
59}
60
61func BenchmarkUint32Mod7(b *testing.B)         { bmUint32Mod(7, b) }
62func BenchmarkUint32Mod37(b *testing.B)        { bmUint32Mod(37, b) }
63func BenchmarkUint32Mod123(b *testing.B)       { bmUint32Mod(123, b) }
64func BenchmarkUint32Mod763(b *testing.B)       { bmUint32Mod(763, b) }
65func BenchmarkUint32Mod1247(b *testing.B)      { bmUint32Mod(1247, b) }
66func BenchmarkUint32Mod9305(b *testing.B)      { bmUint32Mod(9305, b) }
67func BenchmarkUint32Mod13307(b *testing.B)     { bmUint32Mod(13307, b) }
68func BenchmarkUint32Mod52513(b *testing.B)     { bmUint32Mod(52513, b) }
69func BenchmarkUint32Mod60978747(b *testing.B)  { bmUint32Mod(60978747, b) }
70func BenchmarkUint32Mod106956295(b *testing.B) { bmUint32Mod(106956295, b) }
71