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 benchmark, taken from the shootuot, tests floating point performance. 6 7 package go1 8 9 import "testing" 10 11 func mandelbrot(n int) int { 12 const Iter = 50 13 const Zero float64 = 0 14 const Limit = 2.0 15 ok := 0 16 for y := 0; y < n; y++ { 17 for x := 0; x < n; x++ { 18 Zr, Zi, Tr, Ti := Zero, Zero, Zero, Zero 19 Cr := (2*float64(x)/float64(n) - 1.5) 20 Ci := (2*float64(y)/float64(n) - 1.0) 21 22 for i := 0; i < Iter && (Tr+Ti <= Limit*Limit); i++ { 23 Zi = 2*Zr*Zi + Ci 24 Zr = Tr - Ti + Cr 25 Tr = Zr * Zr 26 Ti = Zi * Zi 27 } 28 29 if Tr+Ti <= Limit*Limit { 30 ok++ 31 } 32 } 33 } 34 return ok 35 } 36 37 func BenchmarkMandelbrot200(b *testing.B) { 38 for i := 0; i < b.N; i++ { 39 mandelbrot(200) 40 } 41 } 42
