blob: 1a211196f2f962d0c191519f76a1b0b9169128d9 [file] [log] [blame]
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package runtime_test
import (
"runtime"
"testing"
)
// arm soft division benchmarks adapted from
// http://ridiculousfish.com/files/division_benchmarks.tar.gz
const numeratorsSize = 1 << 21
var numerators = randomNumerators()
type randstate struct {
hi, lo uint32
}
func (r *randstate) rand() uint32 {
r.hi = r.hi<<16 + r.hi>>16
r.hi += r.lo
r.lo += r.hi
return r.hi
}
func randomNumerators() []uint32 {
numerators := make([]uint32, numeratorsSize)
random := &randstate{2147483563, 2147483563 ^ 0x49616E42}
for i := range numerators {
numerators[i] = random.rand()
}
return numerators
}
func bmUint32Div(divisor uint32, b *testing.B) {
var sum uint32
for i := 0; i < b.N; i++ {
sum += numerators[i&(numeratorsSize-1)] / divisor
}
}
func BenchmarkUint32Div7(b *testing.B) { bmUint32Div(7, b) }
func BenchmarkUint32Div37(b *testing.B) { bmUint32Div(37, b) }
func BenchmarkUint32Div123(b *testing.B) { bmUint32Div(123, b) }
func BenchmarkUint32Div763(b *testing.B) { bmUint32Div(763, b) }
func BenchmarkUint32Div1247(b *testing.B) { bmUint32Div(1247, b) }
func BenchmarkUint32Div9305(b *testing.B) { bmUint32Div(9305, b) }
func BenchmarkUint32Div13307(b *testing.B) { bmUint32Div(13307, b) }
func BenchmarkUint32Div52513(b *testing.B) { bmUint32Div(52513, b) }
func BenchmarkUint32Div60978747(b *testing.B) { bmUint32Div(60978747, b) }
func BenchmarkUint32Div106956295(b *testing.B) { bmUint32Div(106956295, b) }
func bmUint32Mod(divisor uint32, b *testing.B) {
var sum uint32
for i := 0; i < b.N; i++ {
sum += numerators[i&(numeratorsSize-1)] % divisor
}
}
func BenchmarkUint32Mod7(b *testing.B) { bmUint32Mod(7, b) }
func BenchmarkUint32Mod37(b *testing.B) { bmUint32Mod(37, b) }
func BenchmarkUint32Mod123(b *testing.B) { bmUint32Mod(123, b) }
func BenchmarkUint32Mod763(b *testing.B) { bmUint32Mod(763, b) }
func BenchmarkUint32Mod1247(b *testing.B) { bmUint32Mod(1247, b) }
func BenchmarkUint32Mod9305(b *testing.B) { bmUint32Mod(9305, b) }
func BenchmarkUint32Mod13307(b *testing.B) { bmUint32Mod(13307, b) }
func BenchmarkUint32Mod52513(b *testing.B) { bmUint32Mod(52513, b) }
func BenchmarkUint32Mod60978747(b *testing.B) { bmUint32Mod(60978747, b) }
func BenchmarkUint32Mod106956295(b *testing.B) { bmUint32Mod(106956295, b) }
func TestUsplit(t *testing.T) {
var den uint32 = 1000000
for _, x := range []uint32{0, 1, 999999, 1000000, 1010101, 0xFFFFFFFF} {
q1, r1 := runtime.Usplit(x)
q2, r2 := x/den, x%den
if q1 != q2 || r1 != r2 {
t.Errorf("%d/1e6, %d%%1e6 = %d, %d, want %d, %d", x, x, q1, r1, q2, r2)
}
}
}