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
5// This file implements a GCD benchmark.
6// Usage: go test math/big -test.bench GCD
7
8package big
9
10import (
11	"math/rand"
12	"testing"
13)
14
15// randInt returns a pseudo-random Int in the range [1<<(size-1), (1<<size) - 1]
16func randInt(r *rand.Rand, size uint) *Int {
17	n := new(Int).Lsh(intOne, size-1)
18	x := new(Int).Rand(r, n)
19	return x.Add(x, n) // make sure result > 1<<(size-1)
20}
21
22func runGCD(b *testing.B, aSize, bSize uint) {
23	if isRaceBuilder && (aSize > 1000 || bSize > 1000) {
24		b.Skip("skipping on race builder")
25	}
26	b.Run("WithoutXY", func(b *testing.B) {
27		runGCDExt(b, aSize, bSize, false)
28	})
29	b.Run("WithXY", func(b *testing.B) {
30		runGCDExt(b, aSize, bSize, true)
31	})
32}
33
34func runGCDExt(b *testing.B, aSize, bSize uint, calcXY bool) {
35	b.StopTimer()
36	var r = rand.New(rand.NewSource(1234))
37	aa := randInt(r, aSize)
38	bb := randInt(r, bSize)
39	var x, y *Int
40	if calcXY {
41		x = new(Int)
42		y = new(Int)
43	}
44	b.StartTimer()
45	for i := 0; i < b.N; i++ {
46		new(Int).GCD(x, y, aa, bb)
47	}
48}
49
50func BenchmarkGCD10x10(b *testing.B)         { runGCD(b, 10, 10) }
51func BenchmarkGCD10x100(b *testing.B)        { runGCD(b, 10, 100) }
52func BenchmarkGCD10x1000(b *testing.B)       { runGCD(b, 10, 1000) }
53func BenchmarkGCD10x10000(b *testing.B)      { runGCD(b, 10, 10000) }
54func BenchmarkGCD10x100000(b *testing.B)     { runGCD(b, 10, 100000) }
55func BenchmarkGCD100x100(b *testing.B)       { runGCD(b, 100, 100) }
56func BenchmarkGCD100x1000(b *testing.B)      { runGCD(b, 100, 1000) }
57func BenchmarkGCD100x10000(b *testing.B)     { runGCD(b, 100, 10000) }
58func BenchmarkGCD100x100000(b *testing.B)    { runGCD(b, 100, 100000) }
59func BenchmarkGCD1000x1000(b *testing.B)     { runGCD(b, 1000, 1000) }
60func BenchmarkGCD1000x10000(b *testing.B)    { runGCD(b, 1000, 10000) }
61func BenchmarkGCD1000x100000(b *testing.B)   { runGCD(b, 1000, 100000) }
62func BenchmarkGCD10000x10000(b *testing.B)   { runGCD(b, 10000, 10000) }
63func BenchmarkGCD10000x100000(b *testing.B)  { runGCD(b, 10000, 100000) }
64func BenchmarkGCD100000x100000(b *testing.B) { runGCD(b, 100000, 100000) }
65