encoding/gob: simplify allocation in decode.

The old code's structure needed to track indirections because of the
use of unsafe. That is no longer necessary, so we can remove all
that tracking. The code cleans up considerably but is a little slower.
We may be able to recover that performance drop. I believe the
code quality improvement is worthwhile regardless.

BenchmarkEndToEndPipe           5610          5780          +3.03%
BenchmarkEndToEndByteBuffer     3156          3222          +2.09%

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/103700043

1 files changed, 19 insertions, 19 deletions

diff --git a/src/pkg/encoding/gob/codec_test.go b/src/pkg/encoding/gob/codec_test.go
index a6012f55e0..c7b2567ca0 100644
--- a/src/pkg/encoding/gob/codec_test.go
+++ b/src/pkg/encoding/gob/codec_test.go
@@ -323,7 +323,7 @@ func execDec(typ string, instr *decInstr, state *decoderState, t *testing.T, val
 	if v+state.fieldnum != 6 {
 		t.Fatalf("decoding field number %d, got %d", 6, v+state.fieldnum)
 	}
-	instr.op(instr, state, decIndirect(value, instr.indir))
+	instr.op(instr, state, value)
 	state.fieldnum = 6
 }
 
@@ -342,7 +342,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// bool
 	{
 		var data bool
-		instr := &decInstr{decBool, 6, nil, 1, ovfl}
+		instr := &decInstr{decBool, 6, nil, ovfl}
 		state := newDecodeStateFromData(boolResult)
 		execDec("bool", instr, state, t, reflect.ValueOf(&data))
 		if data != true {
@@ -352,7 +352,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// int
 	{
 		var data int
-		instr := &decInstr{decOpTable[reflect.Int], 6, nil, 1, ovfl}
+		instr := &decInstr{decOpTable[reflect.Int], 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
 		execDec("int", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -363,7 +363,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// uint
 	{
 		var data uint
-		instr := &decInstr{decOpTable[reflect.Uint], 6, nil, 1, ovfl}
+		instr := &decInstr{decOpTable[reflect.Uint], 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
 		execDec("uint", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -374,7 +374,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// int8
 	{
 		var data int8
-		instr := &decInstr{decInt8, 6, nil, 1, ovfl}
+		instr := &decInstr{decInt8, 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
 		execDec("int8", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -385,7 +385,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// uint8
 	{
 		var data uint8
-		instr := &decInstr{decUint8, 6, nil, 1, ovfl}
+		instr := &decInstr{decUint8, 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
 		execDec("uint8", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -396,7 +396,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// int16
 	{
 		var data int16
-		instr := &decInstr{decInt16, 6, nil, 1, ovfl}
+		instr := &decInstr{decInt16, 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
 		execDec("int16", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -407,7 +407,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// uint16
 	{
 		var data uint16
-		instr := &decInstr{decUint16, 6, nil, 1, ovfl}
+		instr := &decInstr{decUint16, 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
 		execDec("uint16", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -418,7 +418,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// int32
 	{
 		var data int32
-		instr := &decInstr{decInt32, 6, nil, 1, ovfl}
+		instr := &decInstr{decInt32, 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
 		execDec("int32", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -429,7 +429,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// uint32
 	{
 		var data uint32
-		instr := &decInstr{decUint32, 6, nil, 1, ovfl}
+		instr := &decInstr{decUint32, 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
 		execDec("uint32", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -440,7 +440,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// uintptr
 	{
 		var data uintptr
-		instr := &decInstr{decOpTable[reflect.Uintptr], 6, nil, 1, ovfl}
+		instr := &decInstr{decOpTable[reflect.Uintptr], 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
 		execDec("uintptr", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -451,7 +451,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// int64
 	{
 		var data int64
-		instr := &decInstr{decInt64, 6, nil, 1, ovfl}
+		instr := &decInstr{decInt64, 6, nil, ovfl}
 		state := newDecodeStateFromData(signedResult)
 		execDec("int64", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -462,7 +462,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// uint64
 	{
 		var data uint64
-		instr := &decInstr{decUint64, 6, nil, 1, ovfl}
+		instr := &decInstr{decUint64, 6, nil, ovfl}
 		state := newDecodeStateFromData(unsignedResult)
 		execDec("uint64", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -473,7 +473,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// float32
 	{
 		var data float32
-		instr := &decInstr{decFloat32, 6, nil, 1, ovfl}
+		instr := &decInstr{decFloat32, 6, nil, ovfl}
 		state := newDecodeStateFromData(floatResult)
 		execDec("float32", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -484,7 +484,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// float64
 	{
 		var data float64
-		instr := &decInstr{decFloat64, 6, nil, 1, ovfl}
+		instr := &decInstr{decFloat64, 6, nil, ovfl}
 		state := newDecodeStateFromData(floatResult)
 		execDec("float64", instr, state, t, reflect.ValueOf(&data))
 		if data != 17 {
@@ -495,7 +495,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// complex64
 	{
 		var data complex64
-		instr := &decInstr{decOpTable[reflect.Complex64], 6, nil, 1, ovfl}
+		instr := &decInstr{decOpTable[reflect.Complex64], 6, nil, ovfl}
 		state := newDecodeStateFromData(complexResult)
 		execDec("complex", instr, state, t, reflect.ValueOf(&data))
 		if data != 17+19i {
@@ -506,7 +506,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// complex128
 	{
 		var data complex128
-		instr := &decInstr{decOpTable[reflect.Complex128], 6, nil, 1, ovfl}
+		instr := &decInstr{decOpTable[reflect.Complex128], 6, nil, ovfl}
 		state := newDecodeStateFromData(complexResult)
 		execDec("complex", instr, state, t, reflect.ValueOf(&data))
 		if data != 17+19i {
@@ -517,7 +517,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// bytes == []uint8
 	{
 		var data []byte
-		instr := &decInstr{decUint8Slice, 6, nil, 1, ovfl}
+		instr := &decInstr{decUint8Slice, 6, nil, ovfl}
 		state := newDecodeStateFromData(bytesResult)
 		execDec("bytes", instr, state, t, reflect.ValueOf(&data))
 		if string(data) != "hello" {
@@ -528,7 +528,7 @@ func TestScalarDecInstructions(t *testing.T) {
 	// string
 	{
 		var data string
-		instr := &decInstr{decString, 6, nil, 1, ovfl}
+		instr := &decInstr{decString, 6, nil, ovfl}
 		state := newDecodeStateFromData(bytesResult)
 		execDec("bytes", instr, state, t, reflect.ValueOf(&data))
 		if data != "hello" {