github.com/likebike/go--@v0.0.0-20190911215757-0bd925d16e96/go/src/math/big/gcd_test.go (about)

     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  
     8  package big
     9  
    10  import (
    11  	"math/rand"
    12  	"testing"
    13  )
    14  
    15  // randInt returns a pseudo-random Int in the range [1<<(size-1), (1<<size) - 1]
    16  func 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  
    22  func 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  
    34  func 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  
    50  func BenchmarkGCD10x10(b *testing.B)         { runGCD(b, 10, 10) }
    51  func BenchmarkGCD10x100(b *testing.B)        { runGCD(b, 10, 100) }
    52  func BenchmarkGCD10x1000(b *testing.B)       { runGCD(b, 10, 1000) }
    53  func BenchmarkGCD10x10000(b *testing.B)      { runGCD(b, 10, 10000) }
    54  func BenchmarkGCD10x100000(b *testing.B)     { runGCD(b, 10, 100000) }
    55  func BenchmarkGCD100x100(b *testing.B)       { runGCD(b, 100, 100) }
    56  func BenchmarkGCD100x1000(b *testing.B)      { runGCD(b, 100, 1000) }
    57  func BenchmarkGCD100x10000(b *testing.B)     { runGCD(b, 100, 10000) }
    58  func BenchmarkGCD100x100000(b *testing.B)    { runGCD(b, 100, 100000) }
    59  func BenchmarkGCD1000x1000(b *testing.B)     { runGCD(b, 1000, 1000) }
    60  func BenchmarkGCD1000x10000(b *testing.B)    { runGCD(b, 1000, 10000) }
    61  func BenchmarkGCD1000x100000(b *testing.B)   { runGCD(b, 1000, 100000) }
    62  func BenchmarkGCD10000x10000(b *testing.B)   { runGCD(b, 10000, 10000) }
    63  func BenchmarkGCD10000x100000(b *testing.B)  { runGCD(b, 10000, 100000) }
    64  func BenchmarkGCD100000x100000(b *testing.B) { runGCD(b, 100000, 100000) }