libgo: update to Go1.16beta1 release

This does not yet include support for the //go:embed directive added
in this release.

	* Makefile.am (check-runtime): Don't create check-runtime-dir.
	(mostlyclean-local): Don't remove check-runtime-dir.
	(check-go-tool, check-vet): Copy in go.mod and modules.txt.
	(check-cgo-test, check-carchive-test): Add go.mod file.
	* Makefile.in: Regenerate.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/280172

8 files changed, 78 insertions, 53 deletions

diff --git a/libgo/go/image/color/palette/gen.go b/libgo/go/image/color/palette/gen.go
index f8587db..3243e53 100644
--- a/libgo/go/image/color/palette/gen.go
+++ b/libgo/go/image/color/palette/gen.go
@@ -15,8 +15,8 @@ import (
 	"fmt"
 	"go/format"
 	"io"
-	"io/ioutil"
 	"log"
+	"os"
 )
 
 var filename = flag.String("output", "palette.go", "output file name")
@@ -43,7 +43,7 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	err = ioutil.WriteFile(*filename, data, 0644)
+	err = os.WriteFile(*filename, data, 0644)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/libgo/go/image/gif/reader_test.go b/libgo/go/image/gif/reader_test.go
index 29f47b6..5eec5ec 100644
--- a/libgo/go/image/gif/reader_test.go
+++ b/libgo/go/image/gif/reader_test.go
@@ -11,7 +11,7 @@ import (
 	"image/color"
 	"image/color/palette"
 	"io"
-	"io/ioutil"
+	"os"
 	"reflect"
 	"runtime"
 	"runtime/debug"
@@ -424,7 +424,7 @@ func TestDecodeMemoryConsumption(t *testing.T) {
 }
 
 func BenchmarkDecode(b *testing.B) {
-	data, err := ioutil.ReadFile("../testdata/video-001.gif")
+	data, err := os.ReadFile("../testdata/video-001.gif")
 	if err != nil {
 		b.Fatal(err)
 	}
diff --git a/libgo/go/image/gif/writer_test.go b/libgo/go/image/gif/writer_test.go
index 9b15c8d..af0105c 100644
--- a/libgo/go/image/gif/writer_test.go
+++ b/libgo/go/image/gif/writer_test.go
@@ -9,8 +9,9 @@ import (
 	"image"
 	"image/color"
 	"image/color/palette"
+	"image/draw"
 	_ "image/png"
-	"io/ioutil"
+	"io"
 	"math/rand"
 	"os"
 	"reflect"
@@ -284,7 +285,7 @@ func TestEncodeMismatchDelay(t *testing.T) {
 		Image: images,
 		Delay: make([]int, 1),
 	}
-	if err := EncodeAll(ioutil.Discard, g0); err == nil {
+	if err := EncodeAll(io.Discard, g0); err == nil {
 		t.Error("expected error from mismatched delay and image slice lengths")
 	}
 
@@ -296,13 +297,13 @@ func TestEncodeMismatchDelay(t *testing.T) {
 	for i := range g1.Disposal {
 		g1.Disposal[i] = DisposalNone
 	}
-	if err := EncodeAll(ioutil.Discard, g1); err == nil {
+	if err := EncodeAll(io.Discard, g1); err == nil {
 		t.Error("expected error from mismatched disposal and image slice lengths")
 	}
 }
 
 func TestEncodeZeroGIF(t *testing.T) {
-	if err := EncodeAll(ioutil.Discard, &GIF{}); err == nil {
+	if err := EncodeAll(io.Discard, &GIF{}); err == nil {
 		t.Error("expected error from providing empty gif")
 	}
 }
@@ -323,7 +324,7 @@ func TestEncodeAllFramesOutOfBounds(t *testing.T) {
 				Height: upperBound,
 			},
 		}
-		err := EncodeAll(ioutil.Discard, g)
+		err := EncodeAll(io.Discard, g)
 		if upperBound >= 8 {
 			if err != nil {
 				t.Errorf("upperBound=%d: %v", upperBound, err)
@@ -429,7 +430,7 @@ func TestEncodeImplicitConfigSize(t *testing.T) {
 			Image: images,
 			Delay: make([]int, len(images)),
 		}
-		err := EncodeAll(ioutil.Discard, g)
+		err := EncodeAll(io.Discard, g)
 		if lowerBound >= 0 {
 			if err != nil {
 				t.Errorf("lowerBound=%d: %v", lowerBound, err)
@@ -508,7 +509,7 @@ func TestEncodeBadPalettes(t *testing.T) {
 				}
 			}
 
-			err := EncodeAll(ioutil.Discard, &GIF{
+			err := EncodeAll(io.Discard, &GIF{
 				Image: []*image.Paletted{
 					image.NewPaletted(image.Rect(0, 0, w, h), pal),
 				},
@@ -656,39 +657,28 @@ func TestEncodeWrappedImage(t *testing.T) {
 	}
 }
 
-func BenchmarkEncode(b *testing.B) {
+func BenchmarkEncodeRandomPaletted(b *testing.B) {
+	paletted := image.NewPaletted(image.Rect(0, 0, 640, 480), palette.Plan9)
 	rnd := rand.New(rand.NewSource(123))
-
-	// Restrict to a 256-color paletted image to avoid quantization path.
-	palette := make(color.Palette, 256)
-	for i := range palette {
-		palette[i] = color.RGBA{
-			uint8(rnd.Intn(256)),
-			uint8(rnd.Intn(256)),
-			uint8(rnd.Intn(256)),
-			255,
-		}
-	}
-	img := image.NewPaletted(image.Rect(0, 0, 640, 480), palette)
-	for i := range img.Pix {
-		img.Pix[i] = uint8(rnd.Intn(256))
+	for i := range paletted.Pix {
+		paletted.Pix[i] = uint8(rnd.Intn(256))
 	}
 
-	b.SetBytes(640 * 480 * 4)
+	b.SetBytes(640 * 480 * 1)
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img, nil)
+		Encode(io.Discard, paletted, nil)
 	}
 }
 
-func BenchmarkQuantizedEncode(b *testing.B) {
-	img := image.NewRGBA(image.Rect(0, 0, 640, 480))
-	bo := img.Bounds()
+func BenchmarkEncodeRandomRGBA(b *testing.B) {
+	rgba := image.NewRGBA(image.Rect(0, 0, 640, 480))
+	bo := rgba.Bounds()
 	rnd := rand.New(rand.NewSource(123))
 	for y := bo.Min.Y; y < bo.Max.Y; y++ {
 		for x := bo.Min.X; x < bo.Max.X; x++ {
-			img.SetRGBA(x, y, color.RGBA{
+			rgba.SetRGBA(x, y, color.RGBA{
 				uint8(rnd.Intn(256)),
 				uint8(rnd.Intn(256)),
 				uint8(rnd.Intn(256)),
@@ -696,10 +686,49 @@ func BenchmarkQuantizedEncode(b *testing.B) {
 			})
 		}
 	}
+
 	b.SetBytes(640 * 480 * 4)
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img, nil)
+		Encode(io.Discard, rgba, nil)
+	}
+}
+
+func BenchmarkEncodeRealisticPaletted(b *testing.B) {
+	img, err := readImg("../testdata/video-001.png")
+	if err != nil {
+		b.Fatalf("readImg: %v", err)
+	}
+	bo := img.Bounds()
+	paletted := image.NewPaletted(bo, palette.Plan9)
+	draw.Draw(paletted, bo, img, bo.Min, draw.Src)
+
+	b.SetBytes(int64(bo.Dx() * bo.Dy() * 1))
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		Encode(io.Discard, paletted, nil)
+	}
+}
+
+func BenchmarkEncodeRealisticRGBA(b *testing.B) {
+	img, err := readImg("../testdata/video-001.png")
+	if err != nil {
+		b.Fatalf("readImg: %v", err)
+	}
+	bo := img.Bounds()
+	// Converting img to rgba is redundant for video-001.png, which is already
+	// in the RGBA format, but for those copy/pasting this benchmark (but
+	// changing the source image), the conversion ensures that we're still
+	// benchmarking encoding an RGBA image.
+	rgba := image.NewRGBA(bo)
+	draw.Draw(rgba, bo, img, bo.Min, draw.Src)
+
+	b.SetBytes(int64(bo.Dx() * bo.Dy() * 4))
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		Encode(io.Discard, rgba, nil)
 	}
 }
diff --git a/libgo/go/image/internal/imageutil/gen.go b/libgo/go/image/internal/imageutil/gen.go
index bc85c51..36de5dc 100644
--- a/libgo/go/image/internal/imageutil/gen.go
+++ b/libgo/go/image/internal/imageutil/gen.go
@@ -11,7 +11,6 @@ import (
 	"flag"
 	"fmt"
 	"go/format"
-	"io/ioutil"
 	"log"
 	"os"
 )
@@ -36,7 +35,7 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	if err := ioutil.WriteFile("impl.go", out, 0660); err != nil {
+	if err := os.WriteFile("impl.go", out, 0660); err != nil {
 		log.Fatal(err)
 	}
 }
diff --git a/libgo/go/image/jpeg/reader_test.go b/libgo/go/image/jpeg/reader_test.go
index 1e2798c..bf07fad 100644
--- a/libgo/go/image/jpeg/reader_test.go
+++ b/libgo/go/image/jpeg/reader_test.go
@@ -11,7 +11,6 @@ import (
 	"image"
 	"image/color"
 	"io"
-	"io/ioutil"
 	"math/rand"
 	"os"
 	"strings"
@@ -118,7 +117,7 @@ func (r *eofReader) Read(b []byte) (n int, err error) {
 
 func TestDecodeEOF(t *testing.T) {
 	// Check that if reader returns final data and EOF at same time, jpeg handles it.
-	data, err := ioutil.ReadFile("../testdata/video-001.jpeg")
+	data, err := os.ReadFile("../testdata/video-001.jpeg")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -189,7 +188,7 @@ func pixString(pix []byte, stride, x, y int) string {
 }
 
 func TestTruncatedSOSDataDoesntPanic(t *testing.T) {
-	b, err := ioutil.ReadFile("../testdata/video-005.gray.q50.jpeg")
+	b, err := os.ReadFile("../testdata/video-005.gray.q50.jpeg")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -493,7 +492,7 @@ func TestExtraneousData(t *testing.T) {
 }
 
 func benchmarkDecode(b *testing.B, filename string) {
-	data, err := ioutil.ReadFile(filename)
+	data, err := os.ReadFile(filename)
 	if err != nil {
 		b.Fatal(err)
 	}
diff --git a/libgo/go/image/jpeg/writer_test.go b/libgo/go/image/jpeg/writer_test.go
index 3aff742..abd5e32 100644
--- a/libgo/go/image/jpeg/writer_test.go
+++ b/libgo/go/image/jpeg/writer_test.go
@@ -10,7 +10,7 @@ import (
 	"image"
 	"image/color"
 	"image/png"
-	"io/ioutil"
+	"io"
 	"math/rand"
 	"os"
 	"testing"
@@ -261,7 +261,7 @@ func BenchmarkEncodeRGBA(b *testing.B) {
 	b.ResetTimer()
 	options := &Options{Quality: 90}
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img, options)
+		Encode(io.Discard, img, options)
 	}
 }
 
@@ -283,6 +283,6 @@ func BenchmarkEncodeYCbCr(b *testing.B) {
 	b.ResetTimer()
 	options := &Options{Quality: 90}
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img, options)
+		Encode(io.Discard, img, options)
 	}
 }
diff --git a/libgo/go/image/png/reader_test.go b/libgo/go/image/png/reader_test.go
index 22c704e..3937685 100644
--- a/libgo/go/image/png/reader_test.go
+++ b/libgo/go/image/png/reader_test.go
@@ -11,7 +11,6 @@ import (
 	"image"
 	"image/color"
 	"io"
-	"io/ioutil"
 	"os"
 	"reflect"
 	"strings"
@@ -785,7 +784,7 @@ func TestDimensionOverflow(t *testing.T) {
 }
 
 func benchmarkDecode(b *testing.B, filename string, bytesPerPixel int) {
-	data, err := ioutil.ReadFile(filename)
+	data, err := os.ReadFile(filename)
 	if err != nil {
 		b.Fatal(err)
 	}
diff --git a/libgo/go/image/png/writer_test.go b/libgo/go/image/png/writer_test.go
index 5d131ff..47aa861 100644
--- a/libgo/go/image/png/writer_test.go
+++ b/libgo/go/image/png/writer_test.go
@@ -12,7 +12,6 @@ import (
 	"image"
 	"image/color"
 	"io"
-	"io/ioutil"
 	"testing"
 )
 
@@ -169,7 +168,7 @@ func TestWriterPaletted(t *testing.T) {
 						t.Error(err)
 						return
 					}
-					n, err := io.Copy(ioutil.Discard, r)
+					n, err := io.Copy(io.Discard, r)
 					if err != nil {
 						t.Errorf("got error while reading image data: %v", err)
 					}
@@ -234,7 +233,7 @@ func BenchmarkEncodeGray(b *testing.B) {
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img)
+		Encode(io.Discard, img)
 	}
 }
 
@@ -259,7 +258,7 @@ func BenchmarkEncodeGrayWithBufferPool(b *testing.B) {
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		e.Encode(ioutil.Discard, img)
+		e.Encode(io.Discard, img)
 	}
 }
 
@@ -279,7 +278,7 @@ func BenchmarkEncodeNRGBOpaque(b *testing.B) {
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img)
+		Encode(io.Discard, img)
 	}
 }
 
@@ -292,7 +291,7 @@ func BenchmarkEncodeNRGBA(b *testing.B) {
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img)
+		Encode(io.Discard, img)
 	}
 }
 
@@ -305,7 +304,7 @@ func BenchmarkEncodePaletted(b *testing.B) {
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img)
+		Encode(io.Discard, img)
 	}
 }
 
@@ -325,7 +324,7 @@ func BenchmarkEncodeRGBOpaque(b *testing.B) {
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img)
+		Encode(io.Discard, img)
 	}
 }
 
@@ -338,6 +337,6 @@ func BenchmarkEncodeRGBA(b *testing.B) {
 	b.ReportAllocs()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Encode(ioutil.Discard, img)
+		Encode(io.Discard, img)
 	}
 }