diff options
Diffstat (limited to 'gcc-4.9/gcc/testsuite/go.test/test/mapnan.go')
-rw-r--r-- | gcc-4.9/gcc/testsuite/go.test/test/mapnan.go | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/gcc-4.9/gcc/testsuite/go.test/test/mapnan.go b/gcc-4.9/gcc/testsuite/go.test/test/mapnan.go new file mode 100644 index 000000000..f081cab01 --- /dev/null +++ b/gcc-4.9/gcc/testsuite/go.test/test/mapnan.go @@ -0,0 +1,56 @@ +// +build darwin linux +// run + +// Copyright 2013 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. + +// Test that NaNs in maps don't go quadratic. + +package main + +import ( + "fmt" + "math" + "time" +) + +func main() { + + // Test that NaNs in maps don't go quadratic. + t := func(n int) time.Duration { + t1 := time.Now() + m := map[float64]int{} + nan := math.NaN() + for i := 0; i < n; i++ { + m[nan] = 1 + } + if len(m) != n { + panic("wrong size map after nan insertion") + } + return time.Since(t1) + } + + // Depending on the machine and OS, this test might be too fast + // to measure with accurate enough granularity. On failure, + // make it run longer, hoping that the timing granularity + // is eventually sufficient. + + n := 30000 // ~8ms user time on a Mid 2011 MacBook Air (1.8 GHz Core i7) + fails := 0 + for { + t1 := t(n) + t2 := t(2 * n) + // should be 2x (linear); allow up to 3x + if t2 < 3*t1 { + return + } + fails++ + if fails == 6 { + panic(fmt.Sprintf("too slow: %d inserts: %v; %d inserts: %v\n", n, t1, 2*n, t2)) + } + if fails < 4 { + n *= 2 + } + } +} |