| // 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. |
| |
| package runtime_test |
| |
| import ( |
| "fmt" |
| "math" |
| "reflect" |
| "runtime" |
| "sort" |
| "strconv" |
| "strings" |
| "sync" |
| "testing" |
| ) |
| |
| // negative zero is a good test because: |
| // 1) 0 and -0 are equal, yet have distinct representations. |
| // 2) 0 is represented as all zeros, -0 isn't. |
| // I'm not sure the language spec actually requires this behavior, |
| // but it's what the current map implementation does. |
| func TestNegativeZero(t *testing.T) { |
| m := make(map[float64]bool, 0) |
| |
| m[+0.0] = true |
| m[math.Copysign(0.0, -1.0)] = true // should overwrite +0 entry |
| |
| if len(m) != 1 { |
| t.Error("length wrong") |
| } |
| |
| for k := range m { |
| if math.Copysign(1.0, k) > 0 { |
| t.Error("wrong sign") |
| } |
| } |
| |
| m = make(map[float64]bool, 0) |
| m[math.Copysign(0.0, -1.0)] = true |
| m[+0.0] = true // should overwrite -0.0 entry |
| |
| if len(m) != 1 { |
| t.Error("length wrong") |
| } |
| |
| for k := range m { |
| if math.Copysign(1.0, k) < 0 { |
| t.Error("wrong sign") |
| } |
| } |
| } |
| |
| // nan is a good test because nan != nan, and nan has |
| // a randomized hash value. |
| func TestNan(t *testing.T) { |
| m := make(map[float64]int, 0) |
| nan := math.NaN() |
| m[nan] = 1 |
| m[nan] = 2 |
| m[nan] = 4 |
| if len(m) != 3 { |
| t.Error("length wrong") |
| } |
| s := 0 |
| for k, v := range m { |
| if k == k { |
| t.Error("nan disappeared") |
| } |
| if (v & (v - 1)) != 0 { |
| t.Error("value wrong") |
| } |
| s |= v |
| } |
| if s != 7 { |
| t.Error("values wrong") |
| } |
| } |
| |
| // Maps aren't actually copied on assignment. |
| func TestAlias(t *testing.T) { |
| m := make(map[int]int, 0) |
| m[0] = 5 |
| n := m |
| n[0] = 6 |
| if m[0] != 6 { |
| t.Error("alias didn't work") |
| } |
| } |
| |
| func TestGrowWithNaN(t *testing.T) { |
| m := make(map[float64]int, 4) |
| nan := math.NaN() |
| m[nan] = 1 |
| m[nan] = 2 |
| m[nan] = 4 |
| cnt := 0 |
| s := 0 |
| growflag := true |
| for k, v := range m { |
| if growflag { |
| // force a hashtable resize |
| for i := 0; i < 100; i++ { |
| m[float64(i)] = i |
| } |
| growflag = false |
| } |
| if k != k { |
| cnt++ |
| s |= v |
| } |
| } |
| if cnt != 3 { |
| t.Error("NaN keys lost during grow") |
| } |
| if s != 7 { |
| t.Error("NaN values lost during grow") |
| } |
| } |
| |
| type FloatInt struct { |
| x float64 |
| y int |
| } |
| |
| func TestGrowWithNegativeZero(t *testing.T) { |
| negzero := math.Copysign(0.0, -1.0) |
| m := make(map[FloatInt]int, 4) |
| m[FloatInt{0.0, 0}] = 1 |
| m[FloatInt{0.0, 1}] = 2 |
| m[FloatInt{0.0, 2}] = 4 |
| m[FloatInt{0.0, 3}] = 8 |
| growflag := true |
| s := 0 |
| cnt := 0 |
| negcnt := 0 |
| // The first iteration should return the +0 key. |
| // The subsequent iterations should return the -0 key. |
| // I'm not really sure this is required by the spec, |
| // but it makes sense. |
| // TODO: are we allowed to get the first entry returned again??? |
| for k, v := range m { |
| if v == 0 { |
| continue |
| } // ignore entries added to grow table |
| cnt++ |
| if math.Copysign(1.0, k.x) < 0 { |
| if v&16 == 0 { |
| t.Error("key/value not updated together 1") |
| } |
| negcnt++ |
| s |= v & 15 |
| } else { |
| if v&16 == 16 { |
| t.Error("key/value not updated together 2", k, v) |
| } |
| s |= v |
| } |
| if growflag { |
| // force a hashtable resize |
| for i := 0; i < 100; i++ { |
| m[FloatInt{3.0, i}] = 0 |
| } |
| // then change all the entries |
| // to negative zero |
| m[FloatInt{negzero, 0}] = 1 | 16 |
| m[FloatInt{negzero, 1}] = 2 | 16 |
| m[FloatInt{negzero, 2}] = 4 | 16 |
| m[FloatInt{negzero, 3}] = 8 | 16 |
| growflag = false |
| } |
| } |
| if s != 15 { |
| t.Error("entry missing", s) |
| } |
| if cnt != 4 { |
| t.Error("wrong number of entries returned by iterator", cnt) |
| } |
| if negcnt != 3 { |
| t.Error("update to negzero missed by iteration", negcnt) |
| } |
| } |
| |
| func TestIterGrowAndDelete(t *testing.T) { |
| m := make(map[int]int, 4) |
| for i := 0; i < 100; i++ { |
| m[i] = i |
| } |
| growflag := true |
| for k := range m { |
| if growflag { |
| // grow the table |
| for i := 100; i < 1000; i++ { |
| m[i] = i |
| } |
| // delete all odd keys |
| for i := 1; i < 1000; i += 2 { |
| delete(m, i) |
| } |
| growflag = false |
| } else { |
| if k&1 == 1 { |
| t.Error("odd value returned") |
| } |
| } |
| } |
| } |
| |
| // make sure old bucket arrays don't get GCd while |
| // an iterator is still using them. |
| func TestIterGrowWithGC(t *testing.T) { |
| m := make(map[int]int, 4) |
| for i := 0; i < 16; i++ { |
| m[i] = i |
| } |
| growflag := true |
| bitmask := 0 |
| for k := range m { |
| if k < 16 { |
| bitmask |= 1 << uint(k) |
| } |
| if growflag { |
| // grow the table |
| for i := 100; i < 1000; i++ { |
| m[i] = i |
| } |
| // trigger a gc |
| runtime.GC() |
| growflag = false |
| } |
| } |
| if bitmask != 1<<16-1 { |
| t.Error("missing key", bitmask) |
| } |
| } |
| |
| func testConcurrentReadsAfterGrowth(t *testing.T, useReflect bool) { |
| t.Parallel() |
| if runtime.GOMAXPROCS(-1) == 1 { |
| defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(16)) |
| } |
| numLoop := 10 |
| numGrowStep := 250 |
| numReader := 16 |
| if testing.Short() { |
| numLoop, numGrowStep = 2, 500 |
| } |
| for i := 0; i < numLoop; i++ { |
| m := make(map[int]int, 0) |
| for gs := 0; gs < numGrowStep; gs++ { |
| m[gs] = gs |
| var wg sync.WaitGroup |
| wg.Add(numReader * 2) |
| for nr := 0; nr < numReader; nr++ { |
| go func() { |
| defer wg.Done() |
| for range m { |
| } |
| }() |
| go func() { |
| defer wg.Done() |
| for key := 0; key < gs; key++ { |
| _ = m[key] |
| } |
| }() |
| if useReflect { |
| wg.Add(1) |
| go func() { |
| defer wg.Done() |
| mv := reflect.ValueOf(m) |
| keys := mv.MapKeys() |
| for _, k := range keys { |
| mv.MapIndex(k) |
| } |
| }() |
| } |
| } |
| wg.Wait() |
| } |
| } |
| } |
| |
| func TestConcurrentReadsAfterGrowth(t *testing.T) { |
| testConcurrentReadsAfterGrowth(t, false) |
| } |
| |
| func TestConcurrentReadsAfterGrowthReflect(t *testing.T) { |
| testConcurrentReadsAfterGrowth(t, true) |
| } |
| |
| func TestBigItems(t *testing.T) { |
| var key [256]string |
| for i := 0; i < 256; i++ { |
| key[i] = "foo" |
| } |
| m := make(map[[256]string][256]string, 4) |
| for i := 0; i < 100; i++ { |
| key[37] = fmt.Sprintf("string%02d", i) |
| m[key] = key |
| } |
| var keys [100]string |
| var values [100]string |
| i := 0 |
| for k, v := range m { |
| keys[i] = k[37] |
| values[i] = v[37] |
| i++ |
| } |
| sort.Strings(keys[:]) |
| sort.Strings(values[:]) |
| for i := 0; i < 100; i++ { |
| if keys[i] != fmt.Sprintf("string%02d", i) { |
| t.Errorf("#%d: missing key: %v", i, keys[i]) |
| } |
| if values[i] != fmt.Sprintf("string%02d", i) { |
| t.Errorf("#%d: missing value: %v", i, values[i]) |
| } |
| } |
| } |
| |
| func TestMapHugeZero(t *testing.T) { |
| type T [4000]byte |
| m := map[int]T{} |
| x := m[0] |
| if x != (T{}) { |
| t.Errorf("map value not zero") |
| } |
| y, ok := m[0] |
| if ok { |
| t.Errorf("map value should be missing") |
| } |
| if y != (T{}) { |
| t.Errorf("map value not zero") |
| } |
| } |
| |
| type empty struct { |
| } |
| |
| func TestEmptyKeyAndValue(t *testing.T) { |
| a := make(map[int]empty, 4) |
| b := make(map[empty]int, 4) |
| c := make(map[empty]empty, 4) |
| a[0] = empty{} |
| b[empty{}] = 0 |
| b[empty{}] = 1 |
| c[empty{}] = empty{} |
| |
| if len(a) != 1 { |
| t.Errorf("empty value insert problem") |
| } |
| if b[empty{}] != 1 { |
| t.Errorf("empty key returned wrong value") |
| } |
| } |
| |
| // Tests a map with a single bucket, with same-lengthed short keys |
| // ("quick keys") as well as long keys. |
| func TestSingleBucketMapStringKeys_DupLen(t *testing.T) { |
| testMapLookups(t, map[string]string{ |
| "x": "x1val", |
| "xx": "x2val", |
| "foo": "fooval", |
| "bar": "barval", // same key length as "foo" |
| "xxxx": "x4val", |
| strings.Repeat("x", 128): "longval1", |
| strings.Repeat("y", 128): "longval2", |
| }) |
| } |
| |
| // Tests a map with a single bucket, with all keys having different lengths. |
| func TestSingleBucketMapStringKeys_NoDupLen(t *testing.T) { |
| testMapLookups(t, map[string]string{ |
| "x": "x1val", |
| "xx": "x2val", |
| "foo": "fooval", |
| "xxxx": "x4val", |
| "xxxxx": "x5val", |
| "xxxxxx": "x6val", |
| strings.Repeat("x", 128): "longval", |
| }) |
| } |
| |
| func testMapLookups(t *testing.T, m map[string]string) { |
| for k, v := range m { |
| if m[k] != v { |
| t.Fatalf("m[%q] = %q; want %q", k, m[k], v) |
| } |
| } |
| } |
| |
| // Tests whether the iterator returns the right elements when |
| // started in the middle of a grow, when the keys are NaNs. |
| func TestMapNanGrowIterator(t *testing.T) { |
| m := make(map[float64]int) |
| nan := math.NaN() |
| const nBuckets = 16 |
| // To fill nBuckets buckets takes LOAD * nBuckets keys. |
| nKeys := int(nBuckets * *runtime.HashLoad) |
| |
| // Get map to full point with nan keys. |
| for i := 0; i < nKeys; i++ { |
| m[nan] = i |
| } |
| // Trigger grow |
| m[1.0] = 1 |
| delete(m, 1.0) |
| |
| // Run iterator |
| found := make(map[int]struct{}) |
| for _, v := range m { |
| if v != -1 { |
| if _, repeat := found[v]; repeat { |
| t.Fatalf("repeat of value %d", v) |
| } |
| found[v] = struct{}{} |
| } |
| if len(found) == nKeys/2 { |
| // Halfway through iteration, finish grow. |
| for i := 0; i < nBuckets; i++ { |
| delete(m, 1.0) |
| } |
| } |
| } |
| if len(found) != nKeys { |
| t.Fatalf("missing value") |
| } |
| } |
| |
| func TestMapIterOrder(t *testing.T) { |
| for _, n := range [...]int{3, 7, 9, 15} { |
| for i := 0; i < 1000; i++ { |
| // Make m be {0: true, 1: true, ..., n-1: true}. |
| m := make(map[int]bool) |
| for i := 0; i < n; i++ { |
| m[i] = true |
| } |
| // Check that iterating over the map produces at least two different orderings. |
| ord := func() []int { |
| var s []int |
| for key := range m { |
| s = append(s, key) |
| } |
| return s |
| } |
| first := ord() |
| ok := false |
| for try := 0; try < 100; try++ { |
| if !reflect.DeepEqual(first, ord()) { |
| ok = true |
| break |
| } |
| } |
| if !ok { |
| t.Errorf("Map with n=%d elements had consistent iteration order: %v", n, first) |
| break |
| } |
| } |
| } |
| } |
| |
| // Issue 8410 |
| func TestMapSparseIterOrder(t *testing.T) { |
| // Run several rounds to increase the probability |
| // of failure. One is not enough. |
| NextRound: |
| for round := 0; round < 10; round++ { |
| m := make(map[int]bool) |
| // Add 1000 items, remove 980. |
| for i := 0; i < 1000; i++ { |
| m[i] = true |
| } |
| for i := 20; i < 1000; i++ { |
| delete(m, i) |
| } |
| |
| var first []int |
| for i := range m { |
| first = append(first, i) |
| } |
| |
| // 800 chances to get a different iteration order. |
| // See bug 8736 for why we need so many tries. |
| for n := 0; n < 800; n++ { |
| idx := 0 |
| for i := range m { |
| if i != first[idx] { |
| // iteration order changed. |
| continue NextRound |
| } |
| idx++ |
| } |
| } |
| t.Fatalf("constant iteration order on round %d: %v", round, first) |
| } |
| } |
| |
| func TestMapStringBytesLookup(t *testing.T) { |
| // Use large string keys to avoid small-allocation coalescing, |
| // which can cause AllocsPerRun to report lower counts than it should. |
| m := map[string]int{ |
| "1000000000000000000000000000000000000000000000000": 1, |
| "2000000000000000000000000000000000000000000000000": 2, |
| } |
| buf := []byte("1000000000000000000000000000000000000000000000000") |
| if x := m[string(buf)]; x != 1 { |
| t.Errorf(`m[string([]byte("1"))] = %d, want 1`, x) |
| } |
| buf[0] = '2' |
| if x := m[string(buf)]; x != 2 { |
| t.Errorf(`m[string([]byte("2"))] = %d, want 2`, x) |
| } |
| |
| var x int |
| n := testing.AllocsPerRun(100, func() { |
| x += m[string(buf)] |
| }) |
| if n != 0 { |
| t.Errorf("AllocsPerRun for m[string(buf)] = %v, want 0", n) |
| } |
| |
| x = 0 |
| n = testing.AllocsPerRun(100, func() { |
| y, ok := m[string(buf)] |
| if !ok { |
| panic("!ok") |
| } |
| x += y |
| }) |
| if n != 0 { |
| t.Errorf("AllocsPerRun for x,ok = m[string(buf)] = %v, want 0", n) |
| } |
| } |
| |
| func TestMapLargeKeyNoPointer(t *testing.T) { |
| const ( |
| I = 1000 |
| N = 64 |
| ) |
| type T [N]int |
| m := make(map[T]int) |
| for i := 0; i < I; i++ { |
| var v T |
| for j := 0; j < N; j++ { |
| v[j] = i + j |
| } |
| m[v] = i |
| } |
| runtime.GC() |
| for i := 0; i < I; i++ { |
| var v T |
| for j := 0; j < N; j++ { |
| v[j] = i + j |
| } |
| if m[v] != i { |
| t.Fatalf("corrupted map: want %+v, got %+v", i, m[v]) |
| } |
| } |
| } |
| |
| func TestMapLargeValNoPointer(t *testing.T) { |
| const ( |
| I = 1000 |
| N = 64 |
| ) |
| type T [N]int |
| m := make(map[int]T) |
| for i := 0; i < I; i++ { |
| var v T |
| for j := 0; j < N; j++ { |
| v[j] = i + j |
| } |
| m[i] = v |
| } |
| runtime.GC() |
| for i := 0; i < I; i++ { |
| var v T |
| for j := 0; j < N; j++ { |
| v[j] = i + j |
| } |
| v1 := m[i] |
| for j := 0; j < N; j++ { |
| if v1[j] != v[j] { |
| t.Fatalf("corrupted map: want %+v, got %+v", v, v1) |
| } |
| } |
| } |
| } |
| |
| // Test that making a map with a large or invalid hint |
| // doesn't panic. (Issue 19926). |
| func TestIgnoreBogusMapHint(t *testing.T) { |
| for _, hint := range []int64{-1, 1 << 62} { |
| _ = make(map[int]int, hint) |
| } |
| } |
| |
| func benchmarkMapPop(b *testing.B, n int) { |
| m := map[int]int{} |
| for i := 0; i < b.N; i++ { |
| for j := 0; j < n; j++ { |
| m[j] = j |
| } |
| for j := 0; j < n; j++ { |
| // Use iterator to pop an element. |
| // We want this to be fast, see issue 8412. |
| for k := range m { |
| delete(m, k) |
| break |
| } |
| } |
| } |
| } |
| |
| func BenchmarkMapPop100(b *testing.B) { benchmarkMapPop(b, 100) } |
| func BenchmarkMapPop1000(b *testing.B) { benchmarkMapPop(b, 1000) } |
| func BenchmarkMapPop10000(b *testing.B) { benchmarkMapPop(b, 10000) } |
| |
| func TestNonEscapingMap(t *testing.T) { |
| n := testing.AllocsPerRun(1000, func() { |
| m := make(map[int]int) |
| m[0] = 0 |
| }) |
| if n != 0 { |
| t.Fatalf("want 0 allocs, got %v", n) |
| } |
| } |
| |
| func benchmarkMapAssignInt32(b *testing.B, n int) { |
| a := make(map[int32]int) |
| for i := 0; i < b.N; i++ { |
| a[int32(i&(n-1))] = i |
| } |
| } |
| |
| func benchmarkMapDeleteInt32(b *testing.B, n int) { |
| a := make(map[int32]int, n*b.N) |
| for i := 0; i < n*b.N; i++ { |
| a[int32(i)] = i |
| } |
| b.ResetTimer() |
| for i := 0; i < n*b.N; i = i + n { |
| delete(a, int32(i)) |
| } |
| } |
| |
| func benchmarkMapAssignInt64(b *testing.B, n int) { |
| a := make(map[int64]int) |
| for i := 0; i < b.N; i++ { |
| a[int64(i&(n-1))] = i |
| } |
| } |
| |
| func benchmarkMapDeleteInt64(b *testing.B, n int) { |
| a := make(map[int64]int, n*b.N) |
| for i := 0; i < n*b.N; i++ { |
| a[int64(i)] = i |
| } |
| b.ResetTimer() |
| for i := 0; i < n*b.N; i = i + n { |
| delete(a, int64(i)) |
| } |
| } |
| |
| func benchmarkMapAssignStr(b *testing.B, n int) { |
| k := make([]string, n) |
| for i := 0; i < len(k); i++ { |
| k[i] = strconv.Itoa(i) |
| } |
| b.ResetTimer() |
| a := make(map[string]int) |
| for i := 0; i < b.N; i++ { |
| a[k[i&(n-1)]] = i |
| } |
| } |
| |
| func benchmarkMapDeleteStr(b *testing.B, n int) { |
| k := make([]string, n*b.N) |
| for i := 0; i < n*b.N; i++ { |
| k[i] = strconv.Itoa(i) |
| } |
| a := make(map[string]int, n*b.N) |
| for i := 0; i < n*b.N; i++ { |
| a[k[i]] = i |
| } |
| b.ResetTimer() |
| for i := 0; i < n*b.N; i = i + n { |
| delete(a, k[i]) |
| } |
| } |
| |
| func runWith(f func(*testing.B, int), v ...int) func(*testing.B) { |
| return func(b *testing.B) { |
| for _, n := range v { |
| b.Run(strconv.Itoa(n), func(b *testing.B) { f(b, n) }) |
| } |
| } |
| } |
| |
| func BenchmarkMapAssign(b *testing.B) { |
| b.Run("Int32", runWith(benchmarkMapAssignInt32, 1<<8, 1<<16)) |
| b.Run("Int64", runWith(benchmarkMapAssignInt64, 1<<8, 1<<16)) |
| b.Run("Str", runWith(benchmarkMapAssignStr, 1<<8, 1<<16)) |
| } |
| |
| func BenchmarkMapDelete(b *testing.B) { |
| b.Run("Int32", runWith(benchmarkMapDeleteInt32, 1, 2, 4)) |
| b.Run("Int64", runWith(benchmarkMapDeleteInt64, 1, 2, 4)) |
| b.Run("Str", runWith(benchmarkMapDeleteStr, 1, 2, 4)) |
| } |