libgo: update to Go1.14beta1

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/214297

1 files changed, 510 insertions, 0 deletions

diff --git a/libgo/go/runtime/mpallocbits_test.go b/libgo/go/runtime/mpallocbits_test.go
new file mode 100644
index 00000000000..71a29f3b3a2
--- /dev/null
+++ b/libgo/go/runtime/mpallocbits_test.go
@@ -0,0 +1,510 @@
+// Copyright 2019 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/rand"
+	. "runtime"
+	"testing"
+)
+
+// Ensures that got and want are the same, and if not, reports
+// detailed diff information.
+func checkPallocBits(t *testing.T, got, want *PallocBits) bool {
+	d := DiffPallocBits(got, want)
+	if len(d) != 0 {
+		t.Errorf("%d range(s) different", len(d))
+		for _, bits := range d {
+			t.Logf("\t@ bit index %d", bits.I)
+			t.Logf("\t|  got: %s", StringifyPallocBits(got, bits))
+			t.Logf("\t| want: %s", StringifyPallocBits(want, bits))
+		}
+		return false
+	}
+	return true
+}
+
+// makePallocBits produces an initialized PallocBits by setting
+// the ranges in s to 1 and the rest to zero.
+func makePallocBits(s []BitRange) *PallocBits {
+	b := new(PallocBits)
+	for _, v := range s {
+		b.AllocRange(v.I, v.N)
+	}
+	return b
+}
+
+// Ensures that PallocBits.AllocRange works, which is a fundamental
+// method used for testing and initialization since it's used by
+// makePallocBits.
+func TestPallocBitsAllocRange(t *testing.T) {
+	test := func(t *testing.T, i, n uint, want *PallocBits) {
+		checkPallocBits(t, makePallocBits([]BitRange{{i, n}}), want)
+	}
+	t.Run("OneLow", func(t *testing.T) {
+		want := new(PallocBits)
+		want[0] = 0x1
+		test(t, 0, 1, want)
+	})
+	t.Run("OneHigh", func(t *testing.T) {
+		want := new(PallocBits)
+		want[PallocChunkPages/64-1] = 1 << 63
+		test(t, PallocChunkPages-1, 1, want)
+	})
+	t.Run("Inner", func(t *testing.T) {
+		want := new(PallocBits)
+		want[2] = 0x3e
+		test(t, 129, 5, want)
+	})
+	t.Run("Aligned", func(t *testing.T) {
+		want := new(PallocBits)
+		want[2] = ^uint64(0)
+		want[3] = ^uint64(0)
+		test(t, 128, 128, want)
+	})
+	t.Run("Begin", func(t *testing.T) {
+		want := new(PallocBits)
+		want[0] = ^uint64(0)
+		want[1] = ^uint64(0)
+		want[2] = ^uint64(0)
+		want[3] = ^uint64(0)
+		want[4] = ^uint64(0)
+		want[5] = 0x1
+		test(t, 0, 321, want)
+	})
+	t.Run("End", func(t *testing.T) {
+		want := new(PallocBits)
+		want[PallocChunkPages/64-1] = ^uint64(0)
+		want[PallocChunkPages/64-2] = ^uint64(0)
+		want[PallocChunkPages/64-3] = ^uint64(0)
+		want[PallocChunkPages/64-4] = 1 << 63
+		test(t, PallocChunkPages-(64*3+1), 64*3+1, want)
+	})
+	t.Run("All", func(t *testing.T) {
+		want := new(PallocBits)
+		for i := range want {
+			want[i] = ^uint64(0)
+		}
+		test(t, 0, PallocChunkPages, want)
+	})
+}
+
+// Inverts every bit in the PallocBits.
+func invertPallocBits(b *PallocBits) {
+	for i := range b {
+		b[i] = ^b[i]
+	}
+}
+
+// Ensures two packed summaries are identical, and reports a detailed description
+// of the difference if they're not.
+func checkPallocSum(t *testing.T, got, want PallocSum) {
+	if got.Start() != want.Start() {
+		t.Errorf("inconsistent start: got %d, want %d", got.Start(), want.Start())
+	}
+	if got.Max() != want.Max() {
+		t.Errorf("inconsistent max: got %d, want %d", got.Max(), want.Max())
+	}
+	if got.End() != want.End() {
+		t.Errorf("inconsistent end: got %d, want %d", got.End(), want.End())
+	}
+}
+
+func TestMallocBitsPopcntRange(t *testing.T) {
+	type test struct {
+		i, n uint // bit range to popcnt over.
+		want uint // expected popcnt result on that range.
+	}
+	tests := map[string]struct {
+		init  []BitRange // bit ranges to set to 1 in the bitmap.
+		tests []test     // a set of popcnt tests to run over the bitmap.
+	}{
+		"None": {
+			tests: []test{
+				{0, 1, 0},
+				{5, 3, 0},
+				{2, 11, 0},
+				{PallocChunkPages/4 + 1, PallocChunkPages / 2, 0},
+				{0, PallocChunkPages, 0},
+			},
+		},
+		"All": {
+			init: []BitRange{{0, PallocChunkPages}},
+			tests: []test{
+				{0, 1, 1},
+				{5, 3, 3},
+				{2, 11, 11},
+				{PallocChunkPages/4 + 1, PallocChunkPages / 2, PallocChunkPages / 2},
+				{0, PallocChunkPages, PallocChunkPages},
+			},
+		},
+		"Half": {
+			init: []BitRange{{PallocChunkPages / 2, PallocChunkPages / 2}},
+			tests: []test{
+				{0, 1, 0},
+				{5, 3, 0},
+				{2, 11, 0},
+				{PallocChunkPages/2 - 1, 1, 0},
+				{PallocChunkPages / 2, 1, 1},
+				{PallocChunkPages/2 + 10, 1, 1},
+				{PallocChunkPages/2 - 1, 2, 1},
+				{PallocChunkPages / 4, PallocChunkPages / 4, 0},
+				{PallocChunkPages / 4, PallocChunkPages/4 + 1, 1},
+				{PallocChunkPages/4 + 1, PallocChunkPages / 2, PallocChunkPages/4 + 1},
+				{0, PallocChunkPages, PallocChunkPages / 2},
+			},
+		},
+		"OddBound": {
+			init: []BitRange{{0, 111}},
+			tests: []test{
+				{0, 1, 1},
+				{5, 3, 3},
+				{2, 11, 11},
+				{110, 2, 1},
+				{99, 50, 12},
+				{110, 1, 1},
+				{111, 1, 0},
+				{99, 1, 1},
+				{120, 1, 0},
+				{PallocChunkPages / 2, PallocChunkPages / 2, 0},
+				{0, PallocChunkPages, 111},
+			},
+		},
+		"Scattered": {
+			init: []BitRange{
+				{1, 3}, {5, 1}, {7, 1}, {10, 2}, {13, 1}, {15, 4},
+				{21, 1}, {23, 1}, {26, 2}, {30, 5}, {36, 2}, {40, 3},
+				{44, 6}, {51, 1}, {53, 2}, {58, 3}, {63, 1}, {67, 2},
+				{71, 10}, {84, 1}, {89, 7}, {99, 2}, {103, 1}, {107, 2},
+				{111, 1}, {113, 1}, {115, 1}, {118, 1}, {120, 2}, {125, 5},
+			},
+			tests: []test{
+				{0, 11, 6},
+				{0, 64, 39},
+				{13, 64, 40},
+				{64, 64, 34},
+				{0, 128, 73},
+				{1, 128, 74},
+				{0, PallocChunkPages, 75},
+			},
+		},
+	}
+	for name, v := range tests {
+		v := v
+		t.Run(name, func(t *testing.T) {
+			b := makePallocBits(v.init)
+			for _, h := range v.tests {
+				if got := b.PopcntRange(h.i, h.n); got != h.want {
+					t.Errorf("bad popcnt (i=%d, n=%d): got %d, want %d", h.i, h.n, got, h.want)
+				}
+			}
+		})
+	}
+}
+
+// Ensures computing bit summaries works as expected by generating random
+// bitmaps and checking against a reference implementation.
+func TestPallocBitsSummarizeRandom(t *testing.T) {
+	b := new(PallocBits)
+	for i := 0; i < 1000; i++ {
+		// Randomize bitmap.
+		for i := range b {
+			b[i] = rand.Uint64()
+		}
+		// Check summary against reference implementation.
+		checkPallocSum(t, b.Summarize(), SummarizeSlow(b))
+	}
+}
+
+// Ensures computing bit summaries works as expected.
+func TestPallocBitsSummarize(t *testing.T) {
+	var emptySum = PackPallocSum(PallocChunkPages, PallocChunkPages, PallocChunkPages)
+	type test struct {
+		free []BitRange // Ranges of free (zero) bits.
+		hits []PallocSum
+	}
+	tests := make(map[string]test)
+	tests["NoneFree"] = test{
+		free: []BitRange{},
+		hits: []PallocSum{
+			PackPallocSum(0, 0, 0),
+		},
+	}
+	tests["OnlyStart"] = test{
+		free: []BitRange{{0, 10}},
+		hits: []PallocSum{
+			PackPallocSum(10, 10, 0),
+		},
+	}
+	tests["OnlyEnd"] = test{
+		free: []BitRange{{PallocChunkPages - 40, 40}},
+		hits: []PallocSum{
+			PackPallocSum(0, 40, 40),
+		},
+	}
+	tests["StartAndEnd"] = test{
+		free: []BitRange{{0, 11}, {PallocChunkPages - 23, 23}},
+		hits: []PallocSum{
+			PackPallocSum(11, 23, 23),
+		},
+	}
+	tests["StartMaxEnd"] = test{
+		free: []BitRange{{0, 4}, {50, 100}, {PallocChunkPages - 4, 4}},
+		hits: []PallocSum{
+			PackPallocSum(4, 100, 4),
+		},
+	}
+	tests["OnlyMax"] = test{
+		free: []BitRange{{1, 20}, {35, 241}, {PallocChunkPages - 50, 30}},
+		hits: []PallocSum{
+			PackPallocSum(0, 241, 0),
+		},
+	}
+	tests["MultiMax"] = test{
+		free: []BitRange{{35, 2}, {40, 5}, {100, 5}},
+		hits: []PallocSum{
+			PackPallocSum(0, 5, 0),
+		},
+	}
+	tests["One"] = test{
+		free: []BitRange{{2, 1}},
+		hits: []PallocSum{
+			PackPallocSum(0, 1, 0),
+		},
+	}
+	tests["AllFree"] = test{
+		free: []BitRange{{0, PallocChunkPages}},
+		hits: []PallocSum{
+			emptySum,
+		},
+	}
+	for name, v := range tests {
+		v := v
+		t.Run(name, func(t *testing.T) {
+			b := makePallocBits(v.free)
+			// In the PallocBits we create 1's represent free spots, but in our actual
+			// PallocBits 1 means not free, so invert.
+			invertPallocBits(b)
+			for _, h := range v.hits {
+				checkPallocSum(t, b.Summarize(), h)
+			}
+		})
+	}
+}
+
+// Benchmarks how quickly we can summarize a PallocBits.
+func BenchmarkPallocBitsSummarize(b *testing.B) {
+	buf0 := new(PallocBits)
+	buf1 := new(PallocBits)
+	for i := 0; i < len(buf1); i++ {
+		buf1[i] = ^uint64(0)
+	}
+	bufa := new(PallocBits)
+	for i := 0; i < len(bufa); i++ {
+		bufa[i] = 0xaa
+	}
+	for _, buf := range []*PallocBits{buf0, buf1, bufa} {
+		b.Run(fmt.Sprintf("Unpacked%02X", buf[0]), func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				buf.Summarize()
+			}
+		})
+	}
+}
+
+// Ensures page allocation works.
+func TestPallocBitsAlloc(t *testing.T) {
+	tests := map[string]struct {
+		before []BitRange
+		after  []BitRange
+		npages uintptr
+		hits   []uint
+	}{
+		"AllFree1": {
+			npages: 1,
+			hits:   []uint{0, 1, 2, 3, 4, 5},
+			after:  []BitRange{{0, 6}},
+		},
+		"AllFree2": {
+			npages: 2,
+			hits:   []uint{0, 2, 4, 6, 8, 10},
+			after:  []BitRange{{0, 12}},
+		},
+		"AllFree5": {
+			npages: 5,
+			hits:   []uint{0, 5, 10, 15, 20},
+			after:  []BitRange{{0, 25}},
+		},
+		"AllFree64": {
+			npages: 64,
+			hits:   []uint{0, 64, 128},
+			after:  []BitRange{{0, 192}},
+		},
+		"AllFree65": {
+			npages: 65,
+			hits:   []uint{0, 65, 130},
+			after:  []BitRange{{0, 195}},
+		},
+		"SomeFree64": {
+			before: []BitRange{{0, 32}, {64, 32}, {100, PallocChunkPages - 100}},
+			npages: 64,
+			hits:   []uint{^uint(0)},
+			after:  []BitRange{{0, 32}, {64, 32}, {100, PallocChunkPages - 100}},
+		},
+		"NoneFree1": {
+			before: []BitRange{{0, PallocChunkPages}},
+			npages: 1,
+			hits:   []uint{^uint(0), ^uint(0)},
+			after:  []BitRange{{0, PallocChunkPages}},
+		},
+		"NoneFree2": {
+			before: []BitRange{{0, PallocChunkPages}},
+			npages: 2,
+			hits:   []uint{^uint(0), ^uint(0)},
+			after:  []BitRange{{0, PallocChunkPages}},
+		},
+		"NoneFree5": {
+			before: []BitRange{{0, PallocChunkPages}},
+			npages: 5,
+			hits:   []uint{^uint(0), ^uint(0)},
+			after:  []BitRange{{0, PallocChunkPages}},
+		},
+		"NoneFree65": {
+			before: []BitRange{{0, PallocChunkPages}},
+			npages: 65,
+			hits:   []uint{^uint(0), ^uint(0)},
+			after:  []BitRange{{0, PallocChunkPages}},
+		},
+		"ExactFit1": {
+			before: []BitRange{{0, PallocChunkPages/2 - 3}, {PallocChunkPages/2 - 2, PallocChunkPages/2 + 2}},
+			npages: 1,
+			hits:   []uint{PallocChunkPages/2 - 3, ^uint(0)},
+			after:  []BitRange{{0, PallocChunkPages}},
+		},
+		"ExactFit2": {
+			before: []BitRange{{0, PallocChunkPages/2 - 3}, {PallocChunkPages/2 - 1, PallocChunkPages/2 + 1}},
+			npages: 2,
+			hits:   []uint{PallocChunkPages/2 - 3, ^uint(0)},
+			after:  []BitRange{{0, PallocChunkPages}},
+		},
+		"ExactFit5": {
+			before: []BitRange{{0, PallocChunkPages/2 - 3}, {PallocChunkPages/2 + 2, PallocChunkPages/2 - 2}},
+			npages: 5,
+			hits:   []uint{PallocChunkPages/2 - 3, ^uint(0)},
+			after:  []BitRange{{0, PallocChunkPages}},
+		},
+		"ExactFit65": {
+			before: []BitRange{{0, PallocChunkPages/2 - 31}, {PallocChunkPages/2 + 34, PallocChunkPages/2 - 34}},
+			npages: 65,
+			hits:   []uint{PallocChunkPages/2 - 31, ^uint(0)},
+			after:  []BitRange{{0, PallocChunkPages}},
+		},
+		"SomeFree161": {
+			before: []BitRange{{0, 185}, {331, 1}},
+			npages: 161,
+			hits:   []uint{332},
+			after:  []BitRange{{0, 185}, {331, 162}},
+		},
+	}
+	for name, v := range tests {
+		v := v
+		t.Run(name, func(t *testing.T) {
+			b := makePallocBits(v.before)
+			for iter, i := range v.hits {
+				a, _ := b.Find(v.npages, 0)
+				if i != a {
+					t.Fatalf("find #%d picked wrong index: want %d, got %d", iter+1, i, a)
+				}
+				if i != ^uint(0) {
+					b.AllocRange(a, uint(v.npages))
+				}
+			}
+			want := makePallocBits(v.after)
+			checkPallocBits(t, b, want)
+		})
+	}
+}
+
+// Ensures page freeing works.
+func TestPallocBitsFree(t *testing.T) {
+	tests := map[string]struct {
+		beforeInv []BitRange
+		afterInv  []BitRange
+		frees     []uint
+		npages    uintptr
+	}{
+		"SomeFree": {
+			npages:    1,
+			beforeInv: []BitRange{{0, 32}, {64, 32}, {100, 1}},
+			frees:     []uint{32},
+			afterInv:  []BitRange{{0, 33}, {64, 32}, {100, 1}},
+		},
+		"NoneFree1": {
+			npages:   1,
+			frees:    []uint{0, 1, 2, 3, 4, 5},
+			afterInv: []BitRange{{0, 6}},
+		},
+		"NoneFree2": {
+			npages:   2,
+			frees:    []uint{0, 2, 4, 6, 8, 10},
+			afterInv: []BitRange{{0, 12}},
+		},
+		"NoneFree5": {
+			npages:   5,
+			frees:    []uint{0, 5, 10, 15, 20},
+			afterInv: []BitRange{{0, 25}},
+		},
+		"NoneFree64": {
+			npages:   64,
+			frees:    []uint{0, 64, 128},
+			afterInv: []BitRange{{0, 192}},
+		},
+		"NoneFree65": {
+			npages:   65,
+			frees:    []uint{0, 65, 130},
+			afterInv: []BitRange{{0, 195}},
+		},
+	}
+	for name, v := range tests {
+		v := v
+		t.Run(name, func(t *testing.T) {
+			b := makePallocBits(v.beforeInv)
+			invertPallocBits(b)
+			for _, i := range v.frees {
+				b.Free(i, uint(v.npages))
+			}
+			want := makePallocBits(v.afterInv)
+			invertPallocBits(want)
+			checkPallocBits(t, b, want)
+		})
+	}
+}
+
+func TestFindBitRange64(t *testing.T) {
+	check := func(x uint64, n uint, result uint) {
+		i := FindBitRange64(x, n)
+		if result == ^uint(0) && i < 64 {
+			t.Errorf("case (%016x, %d): got %d, want failure", x, n, i)
+		} else if result != ^uint(0) && i != result {
+			t.Errorf("case (%016x, %d): got %d, want %d", x, n, i, result)
+		}
+	}
+	for i := uint(0); i <= 64; i++ {
+		check(^uint64(0), i, 0)
+	}
+	check(0, 0, 0)
+	for i := uint(1); i <= 64; i++ {
+		check(0, i, ^uint(0))
+	}
+	check(0x8000000000000000, 1, 63)
+	check(0xc000010001010000, 2, 62)
+	check(0xc000010001030000, 2, 16)
+	check(0xe000030001030000, 3, 61)
+	check(0xe000030001070000, 3, 16)
+	check(0xffff03ff01070000, 16, 48)
+	check(0xffff03ff0107ffff, 16, 0)
+	check(0x0fff03ff01079fff, 16, ^uint(0))
+}